Proceedings Volume 5967

2004 Shanghai International Conference on Laser Medicine and Surgery

Jing Zhu
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Proceedings Volume 5967

2004 Shanghai International Conference on Laser Medicine and Surgery

Jing Zhu
View the digital version of this volume at SPIE Digital Libarary.

Volume Details

Date Published: 25 July 2005
Contents: 8 Sessions, 70 Papers, 0 Presentations
Conference: 2004 Shanghai international Conference on Laser Medicine and Surgery 2004
Volume Number: 5967

Table of Contents

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Table of Contents

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  • Special Lectures and State-of-the Art Lectures
  • Basic Research
  • PDT Treatment
  • Dermatology and Plastic Surgery
  • Otorhinolaryngology
  • ILLLI
  • Ophthalmology
  • Surgery
Special Lectures and State-of-the Art Lectures
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Twenty years history and the future of Asian-Pacific Association of Laser Medicine and Surgery (APLMS)
Kazuhiko Atsumi M.D.
In 1986, APLMS was established to promote the various activities of Laser Medicine Surgery in the Asia-pacific regions. The purpose of APLMS is not only to deliver academic information but also technological, industrial and social ones. Until now, the 9 congresses had been taken place in the different countries in Asia-Pacific regions. As the results of the 18 years' efforts, the organizations of each country on laser medicine and surgery have been established, and the network of researchers and clinicians has been completed. The next challenges are proposed such as education, training, and standardization of methods. To establish guidelines and regulation for laser medicine and surgery, and to transfer technology are also important issues.
The development of laser surgery and medicine in China
Mingzhe Chen
The first Chinese ruby laser was created in 1961 and it was adopted for the retina coagulation experiment in 1965. Since 1970's, lasers had been widely applied clinically including the diseases suitable to physical therapy or acupuncture. The Chinese HpD was first produced in 1981 and first case of PDT was treated using Chinese HpD and Chinese lasers in the same year. Its success brought attention establishing a research group supported by the government in 1982. A nationwide systemic research project on PDT was then carried out. The step taken for PDT also accelerated the development of various fields of laser medicine and surgery. Laser treatments had been commonly adopted in the clinics and hospitals for the diseases of the superficial lesions and the lesions can be reached by the endoscopes non-invasively in 1980's. Since 1990's, the interventional laser therapies adopted mainly were percutaneous laser angioplasty, laser treatments through laparoscope, thoracoscope, arthroscope, neuro-endoscope etc. Ultrasound guided percutaneous laser heat coagulation for small hepatic cancer revealed good results and ultrasound guided percutaneous PDT for advanced large liver cancer revealed unexpected results after five years follow-up. At present: There are more long-term follow-up patients in the clinical trial; more advanced commercial available lasers and new techniques are adopted. Since the popularization of scanning electron microscope, laser scanning confocal microscope, laser induced auto-fluorescence system, high sensitivity fluorescence microscopic imaging system etc. in the laboratories, the basic studies can be more advanced and some times, the sub-cellular level can be reached; ultra-structure histo-morphology and gene studies are involved. In dermatology, Q-switched Alexandrite laser and other Q-switched lasers are used mainly for the treatment of skin pigmentation and vascular diseases; pulsed dye laser, ultra-pulsed CO2 laser are used in resurfacing, facial acne scar, osmidrosis etc. For ophthalmology, excimer laser are used for myopia or hyperopia; argon green laser, krypton yellow laser are adopted in coagulation for retinal detachment and neovascularization etc. Lasers are often used for the canaliculoplasty in the lacrimal canal. Low level lasers had been used very often on the acupuncture points and for many chronic diseases. Intravascular low level laser irradiation adopting semiconductor lasers and He-Ne laser were reported to use for comatose patients, schizophrenia, vascular dementia, Alzeimer's disease and coronary disease. Reports from laboratory studies in the field of low level laser demonstrated the stimulation effect on the cells and immunology system; inhibitory effect on proliferation; it improved the biomedical data in hemorrheology; promoted the spinal motor nerve cell function, axonal regeneration; increased epidermal Langerhams cell to improve the antigen function, increased myocardial capillary permeability. Intra-coronary low power red laser irradiation assisted coronary interventional therapy showed its prevention effect on restenosis. Studies about the effects of various kinds of lasers, their wavelength, power densities and doses on various kinds of tissues were reported.
22 years of photodynamic therapy in China
Jun-Heng Li M.D.
The development of laser medicine in China is correlated with the development of laser science in China. The first Chinese ruby laser was created in 1961. Chinese pharmacists produced the Chinese HpD in 1981 and the first case of PDT was treated using Chinese HpD and Chinese laser equipment in the same year in Beijing. Its success brought attention establishing a research group supported by the government in 1982. A systemic research on PDT was then carried out and obvious results were achieved. The step taken for PDT also accelerated the researches on other kinds of laser medicine and surgery. Since 1982, thousands of patients of malignant tumors including tumors of the lung, esophagus, cardia, stomach, rectum, bladder, other urinary genital organs, face and mouth, eyes, ENT, head and neck, breast, and skin were treated using PDT in China. HpD fluorescence was examined in some centers. Except the superficial tumor cases, PDT procedures were done through the endoscopes. Since 1990's, imaging guided percutaneous PDT was adopted in the organs cannot be reached by the endoscopes, such as liver cancer, peripheral lung cancer and others. PDT can be used for non-malignant cases such as occlusion of blood vessels, for example, we invented the treatment of port wine stains by PDT. Regular surgical operation combined with PDT for cerebral glioma showed to be a very good combination. HpD has been approved by the Chinese Government as a photosensitizer, so it is legal to be used in PDT. There are some second generation photosensitizers under studying in China, such as Hematoporphyrin monomethyl ether (HMME) etc. Lasers used for PDT now are mostly the diode laser of 630nm for the cancers. Research studies for PDT in China may be focalized on the aspects as new photosensitizers; the dosimetry in laser irradiation; atoptosis induced by PDT; preclinical and clinical studies for PDT new indications and new technologies.
CO2 laser: my number one popular laser
Narong Nimsakul
The author with long experiences in using many kinds of laser since 1977, gives overall evaluation of hard ware and soft ware development and applications, and comes to the conclusion that CO2 laser is the number one popular laser in his practice.
Chinese advances in the research of photobiomodulation and its therapeutic applications
Timon Cheng-Yi Liu, Lei Cheng, Jiang Liu, et al.
Photobiomodulation, once called biostimulation, has been studied as the mechanism of low intensity laser therapy since 1982, and it has been studied in China since 1987. Chinese therapeutic applications began in low intensity laser acupuncture in 1970s, in intravascular low intensity laser therapy in 1990s, in endonasal low intensity laser therapy in 1998, in high intensity laser acupuncture in 2000, and in laser surgery in 2001. As Chinese therapeutic applications of photobiomodulation were the most widely in the world, the research of photobiomodulation and its therapeutic applications was very progressive in China. Although the specific pathways mediating photobiomodulation were put forward and studied by foreign experts such as Karu et al, the non-specific pathways were put forward for the first time and were also studied very deeply by Chinese experts such as Liu TCY et al. Moreover, basic research of intravascular low intensity laser therapy, such as in vitro blood research and animal model research, was also very progressive in China.
Mechanisms of tumor destruction caused by photodynamic therapy
Chuannong Zhou
Photodynamic therapy is a relatively new treatment modality and is becoming widely accepted as a standard treatment of a variety of solid tumors. This includes palliative treatments for advanced or obstructive cancers in many organs as well as a curative treatment for some early cancers and pre-cancerous lesions. It has been approved by health authorities in a number of countries in America, Europe and Asia. PDT is a procedure requiring 3 elements: photosensitizer, light and oxygen. The typical technique involves an intravenous administration of a photosensitizing agent, which is preferentially accumulated or retained in tumor tissue, followed by irradiation of the tumor area with light of appropriate wavelength. In the presence of oxygen it generates highly reactive and cytotoxic molecular species, in particular, singlet oxygen (1O2), which may oxidize various bio-molecules and finally leading to cell death and tumor destruction. The most widely used photosensitizer in clinical treatment of cancers is Photofrin (porfimer sodium), and most widely used light sources are lasers of various types, in recent years preferentially, diode laser, which emits a red light of 630 nm wavelength.
Lasers in the skin cosmetic: problems and solutions
Tianwen Gao, Linchao Sun, Chengxin Li, et al.
Though laser cosmetic therapy has advantages of confirmable efficiency, much less side effects and good safety, but there are still many problems. We have applied VersaPulse multi-wavelength laser, VascuLight(PhotoDerm) intensive pulse light(IPL), LightSheer semi-conductor laser, Quantum Photo-rejuvenation instruments, Sharplan 1080S ultrapulse CO2 laser, 1030C ultrapulse CO2 laser, Sharplan Erbium laser, Sharplan ruby laser, Laserscope Orion laser, continous and pulsed Nd:YAG laser, continous Nd:YAP laser, Q-switch 1064/532 laser, ClearTouch curative instrument for acnes to treat more than ten thousand of patients. This article discusses these problems and solutions in current laser cosmetic therapy. Firstly, the biggest problem in nevus flammeus treatment is low curative rate. VascuLight IPL and VersaPulse laser can work well together in nevus flammeus treatment. Secondly, three problems in the treatment of nevus pigmentosus are the recurrence from incomplete therapy, scars due to exceeding treatment and serious results because MMs in early stages are mistaken for nevus pigmentosus. So we think that the right way to treat nevi is to remove them by surgery and perform a pathological examination. Thirdly, as to the problems of photo-rejuvenation and rhytidectomy, the sequence of therapy efficiency from better to worse is the ultrapulse CO2 laser, the Erbium laser and IPL. Despite good effect, the CO2 laser does not fit colored people because of serious pigmentation. The Erbium laser, which leads to less pigmentation than people expected, can be chosen to treat thick wrinkles. The photo-rejuvenation cannot reduce wrinkle obviously. Fourthly, the reputation of photo-rejuvenation with IPL has been denigrated by disordered markets and many inferior instruments.
Development of highly advanced soft x-ray lasers for biomedical and nano-laser medicine applications
H. Kuroda, Rashid A. Ganeev, M. Suzuki, et al.
Current activities on our research of soft X-ray lasers and higher harmonic generations using intense, subpicosecond lasers are reviewed. Especially for soft X-ray lasers we experimentally demonstrate that by longitudinally pumping 2-mm-long molybdenum preformed plasma with high-intensity 475 fs duration laser pulse, a highly directive soft-X-ray laser at 18.9 nm wavelength is generated. The divergence of the beam is evaluated to be of the submillirad order, and only requires pump laser energy of 150 mJ. Simulations show that the pedestal in the main pump pulse can generate electron density and gain profiles with large spatial gradients, which result in the selective amplification of low-order transverse modes. The present result is the demonstration of an efficient and alternative method of improving the spatial coherence of X-ray lasers with amplified spontaneous emission medium, with possibilities of becoming an excellent tool to explore various application experiments. In higher harmonic generation, topics related to observation of blue shift due to collisionless absorption process is described.
Experimental and clinical studies on transmyocardial laser revascularzation (TMLR)
Masayoshi Okada
The number of patients with coronary artery disease has been increasing in Japan and several kinds of treatments have been performed to reduce their cardiovascular diseases. In patients with small branches, or diffuse stenotic lesions of the coronary arteries, on whom coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) cannot be carried out, it has been hemodynamically demonstrated possible to supply arterial blood from the left ventricular cavity to the ischemic myocardium through laser channels. On the basis of excellent experimental studies using mongrel dogs, newly created laser channels 0.2 mm in diameter have been confirmed to be histologically patent even 3 years after transmyocardial revascularization(TMLR). Thus, this method could be applied as an alternative procedure of transmyocardial revascularization. First clinical procedure of TMLR alone was performed on 55 year-old male patient with severe angina pectoris who had undergone pericardiectomy 7 years ago. He had no candidate for percutaneous coronary intervention, or coronary artery bypass grafting, because his left venticle had severe adhesion to the left lung. Therefore, this method was finally carried out. He is getting well after this surgical intervention. This procedure should be recommended for the patient with end-stage coronary artery disease.
Steady-state and time-resolved fluorescence spectra for detection of colonic cancer
Buhong Li, Shusen Xie, Zhenxi Zhang
The steady-state and time-resolved autofluorescence spectroscopic differences between normal and carcinomatous colonic tissues and the optimal excitation wavelengths were studied. The fluorescence excitation wavelengths varying form 260 to 540 nm were used to induce tissue autofluorescence, and the corresponding emission spectra were measured in the range from 280 to 800 nm. These spectra then can be assembled into an excitation-emission matrix (EEM). Significant changes in fluorescence intensity of excitation-emission matrices were observed between normal and tumor colonic tissues. Low NAD(P)H and FAD, and high protoporphyrin IX fluorescence characterize high-grade malignant tissue when compared with normal colonic tissue, and the most marked difference being at the excitation wavelengths of 340, 380, 460 and 540 nm. Furthermore, the average lifetimes for the normal and carcinomatous colonic tissues were about 4.12 and 18.8 ns, respectively. The promising applications of laser-induced autofluorescence for colonic tissue diagnosis are indicated.
Auto-simultaneous laser treatment and Ohshiro's classification of laser treatment
When the laser was first applied in medicine and surgery in the late 1960's and early 1970's, early adopters reported better wound healing and less postoperative pain with laser procedures compared with the same procedure performed with the cold scalpel or with electrothermy, and multiple surgical effects such as incision, vaporization and hemocoagulation could be achieved with the same laser beam. There was thus an added beneficial component which was associated only with laser surgery. This was first recognized as the '?-effect', was then classified by the author as simultaneous laser therapy, but is now more accurately classified by the author as part of the auto-simultaneous aspect of laser treatment. Indeed, with the dramatic increase of the applications of the laser in surgery and medicine over the last 2 decades there has been a parallel increase in the need for a standardized classification of laser treatment. Some classifications have been machine-based, and thus inaccurate because at appropriate parameters, a 'low-power laser' can produce a surgical effect and a 'high power laser', a therapeutic one . A more accurate classification based on the tissue reaction is presented, developed by the author. In addition to this, the author has devised a graphical representation of laser surgical and therapeutic beams whereby the laser type, parameters, penetration depth, and tissue reaction can all be shown in a single illustration, which the author has termed the 'Laser Apple', due to the typical pattern generated when a laser beam is incident on tissue. Laser/tissue reactions fall into three broad groups. If the photoreaction in the tissue is irreversible, then it is classified as high-reactive level laser treatment (HLLT). If some irreversible damage occurs together with reversible photodamage, as in tissue welding, the author refers to this as mid-reactive level laser treatment (MLLT). If the level of reaction in the target tissue is lower than the cells' survival threshold, then this is low reactive-level laser therapy (LLLT). All three of these classifications can occur simultaneously in the one target, and fall under the umbrella of laser treatment (LT). LT is further subdivided into three main types: mono-type LT (Mo-LT, treatment with a single laser system; multi-type LT (Mu-LT, treatment with multiple laser systems); and concomitant LT (Cc-LT), laser treatment in combination, each of which is further subdivided by tissue reaction to give an accurate, treatment-based categorization of laser treatment. When this effect-based classification is combined with and illustrated by the appropriate laser apple pattern, an accurate and simple method of classifying laser/tissue reactions by the reaction, rather than by the laser used to produce the reaction, is achieved. Examples will be given to illustrate the author's new approach to this important concept.
The evaluation of retinal circulation in advanced diabetic retinopathy before and after panretinal laser photocoagulation by scanning laser opthalmoscope
Tadashi Okano
I investigated the effects of panretinal laser photocoagulation (PRP) on the velocity of retinal circulation in diabetic retinopathy. The retinal circulation was evaluated by means of rapid serial fluorescein angiography (FAG), employing scanning laser ophthalmoscope. FAG was conducted at the rate of 30 frames per seconds in video-tape. Disc-to-macula transit time (DMTT) was defined as the parameter to evaluate the retinal circulation. Diabetic 28 eyes with advanced diabetic retinopathy were examined to measure the DMTT before and after PRP. Normal 30 eyes used as control. Mean DMTT decreased from 9.8±1.5 seconds before PRP to 8.2±1.5 seconds after PRP in 28 diabetic eyes. The value with improvement after PRP was significantly shorter than the value before PRP (p < 0.05). These values before and after PRP were significantly longer than that (3.7±0.7 seconds) in normal 30 eyes (p < 0.01). Retinal circulation is retarded in diabetic retinopathy. The retardation of retinal circulation in diabetic retinopathy improves after PRP, but the value after PRP can not recover until the control level. This study was performed to reveal therapeutic effect to panretinal laser photocoagulation (PRP) for the retardation of retinal circulation in diabetic retinopathy. I investigated the effects of PRP on the velocity of retinal circulation in patients with advanced diabetic retinopathy.
Present status of endoscopic surgery in Japan: laparoscopic surgery and laparoscopic assisted surgery for gastric cancer
Yoshiki Hiki, Seigo Kitano
In this report, I would like to explain the latest data from the 7th National Survey 2004, by the Japan Society for Endoscopic Surgery. Next, I will explain you the comment on laparoscopic gastric cancer operation, in particular. We perform the following 3 surgical procedures. (1) Intragastric method (2) Laparoscopic lesion lifting method (3) Laparoscopic assisted gastric resection Mastery of basic techniques and thorough understanding of topographic anatomy are the most important. Furthermore, it is necessary for a surgeon with experience of at least 50 cases of laparoscopic surgery to be involved in surgery as an assistant.
Development of a handy-type laser surgical unit
Yusuke Abe, Koh Wakamatsu, Shigeru Goto
We proposed a concept of a handy-type laser surgical unit for use in outpatient, in ward and in open-air field. To investigate the possibility of the concept, a handy-type semiconductor laser surgical unit was developed experimentally using 2-watts power laser diode with no built-in electrical cooling unit (Peltier chip) and a small rechargeable battery. The drive circuit was constructed with only current limit and ACC circuits. The laser diode was cooled with heat sink and simple fan. Laser irradiation was set to stop at 30 degree Celsius by monitoring the temperature of laser diode with thermistor temperature sensor. With this system, 1.18 watts of laser power at the end of optical fiber with both 600 and 900μm core diameter, and about 30 minutes of continuous irradiating time with Ni-Cd battery (4.8V 1,500mA/h) could be obtained with no over heating in laser diode. The result showed that the high power semiconductor laser could be driven with small battery when specially designed. In an animal experiment, small bleeding could be managed with contact irradiation method. This kind of simple laser surgical unit is considered to be useful for the management of small bleedings in clinical.
The clinical application of Ho:YAG laser
Jing Zhu
The Ho:YAG laser use in the different superficial disease and intracavity disease through endoscopy was introduced. The safe parameters of Ho:YAG laser use in the clinical was given out.
Basic Research
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Determination of the ablation threshold of 1341nm Nd:YAP laser radiation in the larynx of rabbit
Huiyun Lin, Shusen Xie, Buhong Li
The purpose of this investigation is to determinate the ablation threshold of 1341 nm Nd:YAP laser radiation in the larynx of rabbits. In this study, 30 treatments with the Nd:YAP laser were carried out. The laser power of irradiation on tissue surface was varied from 4 to 12 W, while the duration of the irradiation was changed from 1 to 2.5 s in 0.5 s increments. The irradiated sample's surfaces were examined for visible signs of ablation under a reading microscope. The results reveal that 6.29×103 and 5.03×103 J/cm2 were the ablation threshold for vocal cord and epiglottis cartilage respectively. The trend of damage diameter and ablation diameter with energy density are also presented.
Microdegree porlarimetry for glucose concentrations detection
Hong Wang, Yunlong Wei, Qi Zhou, et al.
Optical glucose measurement is an attractive research topic for years. One of the goals is to develop a noninvasive monitoring of long term, instantaneous blood glucose for diabetics. The principle of porlarimetry for glucose detection is introduced and several techniques of microdegree porlarimetry for glucose detection are summarized and the facts that effect measurement are discussed. Current and future research is focusing on the elimination of confounding factors such as other optically active substances for precise glucose detection.
Laser assisted internal mammary artery-coronary artery anastomosis: an experimental study
Hong-Sheng Zhu, Liang-ping Zhang, Lian Feng
Objective: To observe the time required for anastomosis and the reliability for pressure tolerance after internal mammay artery (IMA)-coronary artery anastomosis. Method: Eight sheep underwent thoracotomy and left IMA harvest. In group I (T) the IMA were anastomosed to left anterior descending artery (LAD) with 7-0 prolene suture (n=4) and in group II (LA) IMA were anastomosed to LAD with laser. Result: The time required for laser technique was shorter than that required in suturing technique [117.5±39.48min (total) and 38.25±6.23 min vs 62.5±37.83 min (total) and 20±6.53 min respectively] (p<0.01). Prior to closing thoracotomy both two groups endured the impact of pharmacologic vasopressor. No leakage at the anastomosed site was observed in both groups. After the closure of thoracotomy, well tolerance for both adrenalin and thoracic negative pressure was observed in the two groups. The peak systolic pressure induced by pharmacologic agent was similar in both groups. Neither stenosis nor thrombus or embolism was observed and immediate patency rate in both groups was 100%. Conclusion: Laser assisted technique seems to be favorable for patency rate and could lead to better result after coronary artery bypass grafting (CABG).
The force on the surface of erythrocyte under laser irradiation
J. T. Yu, J. Y. Chen, J. Ma, et al.
The intravenous low power laser irradiation has been applied clinically in china. However the mechanism is still not fully understood. In this work, the stretching force on the surface of erythrocyte under low power laser irradiation was explored. With the total internal reflection apparatus, the refractive indexes of hemoglobin cytoplasm in erythrocyte and the serum outside erythrocyte were determined as 1.380 and 1.351 respectively. Taking the sphere model for erythrocyte, the force on the surface of the erythrocyte due to the hitting of laser beam was calculated with the way of ray optics. It is found that the acting forces of laser on front and back surfaces are just in opposite direction, but with the similar magnitude of 10-2 PN. This couple forces act as the stretching forces to deform the erythrocyte, which may help erythrocytes to improve their deformability.
Experimental study of biological effect on canine stomach in vitro by Nd:YAP laser
Mei-Jue Zhang, Jing Zhu, Hui-Guo Zhang
Objective: To evaluate the biological effect of Nd:YAP laser in different power and irradiation time on canine stomach in vitro. Methods: The canine stomach in vitro was irradiated by Nd:YAP laser with different power and irradiation time. The damage with naked eye, micro and ultramicro structure was observed. Results: The thermal coagulation effect is mostly and the ablation effect is subordinate on biological effect of Nd:YAP laser on canine stomach in vitro. Thermal coagulation and denaturalization time of whole stratum in pathology is 10W, 5s; 20W, 4s; 30W, 2s; 40~60W, 1s. Conclusions: Safety dose of laser beam on canine stomach in vitro is 10W, time less than 5s; 20W, time less than 4s; 30W, time less than 2s. The ablation and thermal coagulation effects of Nd:YAP laser on canine stomach in vitro is positive correlative with power and time.
Experimental study of biological effects on canine bronchia by Nd:YAP laser
Meixiang Qin, Xiaoqing Bao, Jing Zhu
To observe the difference of biological effects on canine bronchia by Nd:YAP laser with different power and irradiation time. Method: The canine bronchia were irradiated with different power and different irradiation time. We observed the effects of ablation and thermal coagulation of different laser settings. We evaluated the damage scale with naked eyes, microscope and electroscope. Result: The thermal coagulation is primary and ablation is secondary. The dose of perforation is 10w, 3s. The diameter of facula is 3mm. Conclusion: (1) The thermal coagulation is primary and ablation is secondary for Nd:YAP laser shinning on canine bronchia. The ablation and thermal coagulation effect of Nd:YAP laser on canine bronchia is relevant to mean power and irradiation time. (2) Safety dose is less than 10w, 3s. The diameter of facula is 3mm.
Expression of fas protein on CD4+ T cells irradiated by low level He-Ne laser in the case of psoriasis
Fan Nie, Jing Zhu, Hui-guo Zhang
Objective: To investigate the influence on the Expression of Fas protein on CD4+ T cells irradiated by low level He-Ne laser in the cases of psoriasis. Methods: the expression of CD4+ T Fas protein was determined in the case of psoriasis (n=5) pre and post-low level laser irradiation (30 min, 60min and 120min) by flow cytometry as compared withthe control (n=5). Results: In the cases of psoriasis, the expression of CD4+ T FAS protein 21.4±3.1% was increased significantly than that of control group 16.8±2.1% pre-irradiation, p<0.05; in the control, there is no difference between pre and post- irradiation, p>0.05; in the cases, the expression of CD4+ T Fas protein wae positively corelated to the irradiation times, when the energy density arrived to 22.92J/cm2 (60 minutes) and 45.84J/cm2 (120minutes), the expression of CD4+ T Fas protein was increased significantly as compared with pre-irradiation, p<0.05. Conclusion: The expression of CD4+ T Fas protein may be increased by low level He-Ne laser irradiation, the uncontrolled status of apoptosis could be corrected.
Experimental study of biological effect by Nd:YAP laser (1.34um)
Jing Zhu, Hui-guo Zhang, Liping Lu
Objective: To evaluate the biological effect of different power, irradiation time of Nd: YAP laser (1341nm). Method: The canine skin, bronchia, stomach, bladder, uterus were irradiated with different irradiation power and time. The effect was observed by naked eyes, light microscope, and electric microscope. Result: Having positive correlation with power and irradiating time, the biological effect of Nd: YAP laser is mainly thermal coagulation effect with some gasified ablation effect. Under the condition where the diameter of faculae irradiating on canine skin was 3 mm, the thermal coagulation dose reaching deep derma was 5W 4s, 10w 1s; the thermal coagulation dose puncturing the whole layer was 5W, 6s, 10W, 4s; the thermal coagulation dose reaching whole stratum was 10W 5s, 20W 4s, 30W 2s, 40-60W 1s on stomach (Thickness 6mm), was 40W, 2s, 30W, 3s, 20W, 4s, 10W, 6s on bladder (Thickness 6mm, irradiation underwater), was 10W, 4s on bronchia (Thickness 2 mm) and was 30W 3s, 20W 5s, 10W 6s on uterus (Thickness 6mm). Conclusion: Having positive correlation with power and irradiating time, the biological effect of Nd: YAP laser is mainly thermal coagulation effect with some gasified ablation effect. Under the condition where the diameter of faculae irradiating on canine skin was 3 mm, it is safe when the dose is 5W, and the irradiating time is less than 4s; the dose is 10W, and the irradiating time is less than 1 s. Under these conditions, the gastric area is used to coagulating and ablating. It is safe when the dose is less than 10W 5s, 20W 4s, 30W 2s. Under these condition, The bladder (thickness 6mm) is coagulated and ablated. It is safe when the dose is no more than 40W, 1s, 30W, 2s, 20W, 3s, 10W, 5s. Under the condition where bronchia (thickness 2mm) is coagulated and ablated, it is safe when the dose is less than 10W, 3s. Under the condition where uterus (thickness 6mm) is coagulated and ablated, it is safe when the dose is less than 30W, 2s, 20W, 4s, 10W, 5s.
Transmyocardial revascularization on canine with Ho:YAG laser: an experimental study
Xiaoqing Bao, Jing Zhu, Hui-Guo Zhang
Background and Objective: To evaluate the efficiency of transmyocardial revascularization with Ho:YAG laser and find out adequate physical parameters of the laser. Materials and Methods: 10 dogs were studied. All the samples were divided into two groups: the laser group (5 dogs) and the control group (5 dogs). Acute myocardial ischemia was induced in all the samples, and transmyocardial laser revascularization (TMLR) was only done in the laser group. We compared the difference of improvement in myocardial perfusion between the two groups with single photon emission computed tomograph (SPECT) and observed the patency of the laser channels and heat injures in the tissue adjacent to the channels with light- and electro-scope. Results: After 4 weeks, the recovery of myocardial perfusion was significantly faster in the laser group than in the control group through SPECT (P<0.05). Most of the laser channels drilled with Ho:YAG laser were filled with fibrin. There were amount of microvessels and erythrocytes inside and around the channels. Only slight heat injures were seen in the tissue adjacent to the channels. Only 20-30 watts were needed in TMLR. Conclusions: Transmyocardial revascularization with Ho:YAG laser limits infarct expansion and reduces myocardial ischemia efficiently. TMLR with Ho:YAG laser can become a new technique to treat ischemic heart disease.
Biological effects on canine uterus by Nd:YAP laser: an experimental study
Xiao-qing Bao, Jing Zhu, Hui-Guo Zhang
Objective: To observe the difference of biological effects on canine uterus by Nd:YAP laser with different power and different irradiation time. Methods: The canine uteri were irradiated with different power and different irradiation time. The effects of ablation and thermal coagulation in different laser settings were observed. The damage scale was evaluated macroscopically, with lightscope and with electroscope. Results: The thermal coagulation is primary and the ablation is secondary. The dose of perforation is 30w, 2s; 20w, 4s and 10w, 5s. Conclusions: The thermal coagulation is primary and the ablation is secondary of Nd:YAP laser on canine uterus. Safety dose is less than 30w, 2s; 20w, 4s or 10w, 5s. The ablation and thermal coagulation effects of Nd:YAP laser on canine uterus are correlation to mean power and irradiation time.
Experimental study on apoptosis induced by semiconductor laser to hair removal and armpit odor treatment
Hongmin Shi, Min Yan, Meijue Zhang
Objective: To observe and explore the effects and mechanism of apoptosis on canine induced by Laser. Try to find a new approach to treat of armpit odor with no traumatism. Method: We used different power of semiconductor Laser to irradiate the black hair canine to observe and evaluate the tissue effects with electroscope, flow cytometry and Tunel technique at different period of time after irradiation. Result: The apoptosis has been observed within the hair follicle cells and apocrine gland cells after irradiation. After repeat irradiation in low power level, more apoptosis has been observed. Conclusion: Apoptosis exists in hair follicle cells and apocrine gland cells after Laser irradiation.
Biological effects on canine bladder by Nd:YAP laser: an experimental study
Hui-guo Zhang, Mei jue Zhang, Jing Zhu
Objective: To observe the difference of biological effects on canine bladder by Nd:YAP laser with different power and different irradiation time. Methods: The canine bladder was irradiated with different power and different irradiation time. The effects of ablation and thermal coagulation in different laser settings were observed. The damage scale was evaluated macroscopically, with microscope and with electroscope. Results: The thermal coagulation effects is mostly and ablation effects is subordinate on the canine bladder by irradiation of Nd:YAP laser on. Pathology vision shows the thermal coagulation dose on perforation is 10W, 6s, 20W, 4s; 30W, 3s; 40W, 2s; 50-60W, 1s; the dose of whole audience wear through is 10W, 6s; 20W, 4s; 30W, 3s; 40W, 2s; 50-60W, 1s. Conclusions: The thermal coagulation effects is mostly and ablation effects is subordinate on biological effect of Nd:YAP laser on canine bladder. The better safety dose is power 10W, duration time less than 6s; power 20W, duration time less than 4s. power 30W, time less than 3s. power 40W, time less than 2s. The ablation and thermal coagulation effects of Nd:YAP laser on canine bladder is homocercal of power and time.
The influence of 630nm semiconductor laser irradiation on rat S180 ascitic tumor cells without photosensitizers
Min Yan, Jing Zhu, Hui-Guo Zhang, et al.
Objective: To study the influence of 630nm semiconductor laser irradiation on rat ascetic tumor cells without photosensitizers. Methods: In this work, rat ascitic tumor cells (S180) were incubation with no photosensitizers. 630nm light (total output 2W) was delivered to tumor cells at different fluence rate: 100, 200, 250mw/cm2 . According to each fluence rate, S180 tumor cells were divided into 5 groups, which were irradiated with various time periods: 20, 15, 10, 5, 3min. In all cases, S180 tumor cells were taken photos. We use the morphology and flow cytometry technique to investigate the apoptosis of tumor cells during the experiment. Results: 1. No obvious morphological difference between test groups and control groups at various time periods during the experiment. 2. No obvious cell apoptosis difference between test groups and control groups using FCM. Conclusion: After irradiated with 630nm semiconductor laser light, rat ascitic tumor cells (S180) with no photosensitizers incubation were not obviously killed or induced apoptosis.
PDT Treatment
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A short-term follow-up study of photodynamic therapy on 23 cases of malignant tumors
Zhuo-Zheng Huang, Chuang Chen, Rongning Yang, et al.
Objective: To summarize the PDT short-term effect on malignant tumors. Method: Made follow-up observation and analysis of 23 cases of various kinds and different stages malignant tumors received photodynamic therapy. Results: Within the 23 cases, through 1-6 months follow-up, the results of tumor lesions treated by PDT are as follows: 15 cases revealed CR, 8 cases had PR and 5 patients died of other causes, nothing involving PDT. Of the 23 cases, 6 early stage tumor patients showed complete remission and no relapse occurred in the follow-up period; 17 cases of advanced stage patients revealed CR or PR effective results. Conclusion: The confined lesion of early stage malignant tumors can be cured by PDT, the advanced stage malignant tumor cases can also present good short-term effect or palliative results. So, PDT is one of the effective therapies for malignant tumors.
Basic research in PDT
Junichi Hayashi, Katsuo Aizawa
Several photosensitisers are known to accumulate selectively in atheromas, regardless of the size of the involved artery. The new photosensitizer, mono-L-aspartyl chlorin e6 (NPe6), specifically accumulates in the atheroma. In the presence of NPe6, the atheroma could be recognized by detecting the specific fluorescence spectrum of NPe6 using a spectrophotometer. We developed a spectrum analysis system and reported that the fluorescence spectra of NPe6 emitted from atherosclerotic plaques on the descending thoracic aorta were recognized by this analysis system with an angioscopic approach in the animal model of atherosclerosis. We also detected the fluorescence spectrum peak at 675 nm of NPe6 laparoscopically only in parts of the abdominal aorta with an atheroma. This spectrum analysis system is useful to recognize the atheroma, but not to recognize the atherosclerotic lesions of the artery as a whole. So, we developed a fluorescence endoscope. Using the endoscopic analysis system, atheromas on the carotid artery were visualized as reddish spots from inside and outside the artery. Then we developed an epifluorescence stereoscope system, and using this device we visualized small coronary atherosclerosis specifically at the beating heart surface. We extensively examined the effects of photodynamic therapy with NPe6 on the atheroma. We studied the change in the lipid components of the atheroma using Fourier transform infrared (FTIR) microspectroscopy. FTIR microspectroscopic analysis showed a dissociation of ester bonds of cholesterol esters in the atheroma after photodynamic therapy. The framework of the atheroma and the lipids accumulated in the atheroma were destroyed. We also evaluated the change in the elastic framework in the atheroma using scanning electron microscopy. The destruction of the architecture of the elastic fiber network in the atheroma was revealed.
The photosensitizer talaporfinum caused microvascular embolization for photodynamic therapy
Liming Li, Katsuo Aizawa
Photodynamic therapy (PDT) has been evolving rapidly in the recent years. A second-generation Photosensitizer mono-1-aspartyl chlorine 6 (Talaporfin / Npe6 / ME2906, Japan Meiji Seika, Ltd.) has been sanctified for the lung cancer clinical PDT by the Japan Ministry of Health, Labor and Welfare. In this paper, Talaporfin was injected to the implant cancer of a mouse a Talaporfin dose of 5mg/kg through intravenous. After 6 hours, the fluorescence images of the mouse were observed with a microscope and a 664 nm diode laser. Effects of therapy were clarified using the different irradiation energies of the laser (50, 100, 200 J/cm2). Both in plasma and in cancer, the concentrations of Talaporfin were analyzed using High Performance Liquid Chromatography (HPLC). Authors find that the higher concentrations of Talaporfin in plasma, the better PDD effect. It is experimentally verified that local microvascular embolisms in the cancer are formed for photodynamic therapy after the Talaporfin injection and the laser irradiation.
Model for monitoring the process of photodynamic therapy in patients
Takato O. Yoshida, Eiji Kohno, Takashi Sakurai, et al.
The photodynamic therapy (PDT) on tumors is quite effective and widely applied but usually carried out without an immediate evaluation of results. We measured the tumor fluorescence in mice with a fiber probe connected to a linear array spectral analyzer (PMA-11, Hamamatsu Photonics). The spectrum showed a transient change in fluorescence color from red to green during Photofrin-mediated PDT. In order to examine the source of green fluorescence, the mitochondria were accessed under a Nipkow disk-scanning confocal microscope in the HeLa cell in culture after labeling them with a red fluorescent protein (DsRed1-mito) and staining the cell with Photofrin (Axcan Scandipharm). Changes in fluorescence color from red to green were observed in the area of mitochondria upon their swelling during irradiation. This finding in vitro provided clear evidence that the change in fluorescence color from red to green observed in vivo was due to the mitochondrial destruction associated with the cell-death by PDT. This technique of spectral monitoring in tumor may be useful for detection of the cell-death signal during PDT in patients.
Diagnose lung cancer by using fluorescence induce from small dose of hematoporphurin
Jing Zhu, Jian Xu, Lin Ke, et al.
Objective: Diagnose lung tumor clinically by using fluorescence induced from small dose of hematoporphyrin. Method : 37 patients were diagnose in which 22 patients with tumor and 15 with non-tumor disease. The patients were intravenously injected small dose of HPD (2mg/kg). The fluorescence signal was analyzed with OMA system. Results: The fluorescence signal of low dose hematoporphyrin can use to diagnose cancer. The total of 37 patients, in which 22 patients suffered tumor, the average fluorescence peak of Itumor/Inomal was 1.24±0.08. We imitated a normal distributive curve, so that most ratio of Itumor/Inomal could be included in the scope of curve. Suppose the lower limit of diagnostic criterion was 1.05. accorded to the criterion 22 is tumor. 15 of them suffered non- tumor. The average of all Itumor/Inomal was 0.98±0.06, there is significant difference between normal and cancer. 13 of 15 is non-tumor, accorded to the criterion. The positive rate was 94.6%
Photodynamic therapy on the ultrastructure of glioma cell
Shaoshan Hu, Ruyou Zhang, Yongri Zheng
OBJECTIVE: the main purpose of this experiment was to study the change of C6 glioma cells' ultrastructure treated by photodynamic therapy (PDT), observe the change of morphology METHOD: Make the model of rat glioma by transplanted C6 glioma cells into caudate nucleus, treated the glioma rat by PDT after two weeks. Observed the difference of subcellular structure before and after PDT by electron microscope. RESULT: Apoptosis and necrosis can be seen after treated by PDT in the C6 glioma, basal membrance damaged, number of cellular organ of endothelial cell of blood capillary declined, tight junction of endothelial cell lengthen and the gap enlarge. The PDT has slightly effect on the nomorl rat's subcellular structue. CONCLUSION: PDT can induce the apoptosis and necrosis of C6 glioma cell. The damage of the ultramicrostructure of mitochondria and endoplasmic reticulum was the foundmentol of the change. PDT initiate the damage of BBB of the C6 glioma cell and weeken the function, and makes it a useful way of treating the glioma combined with chemotherapy.
Research of ALA combined with HpD-PDT which induced S180 ascitic tumor cells, death, or apoptosis on cytology
Jing Zhu, Min Yan, Hui-Guo Zhang, et al.
Objective: To ascertain the adequate dosage of ALA combined with HpD-PDT which induced tumor cell death or apoptosis on cytology. And to study the different effect of ALA-PDT and HPD-PDT used only. Methods: Rat ascitic tumor cells(S180) were randomly divided into several groups and incubated with ALA (20μg/ml, 40μg/ml, 80μg/ml, 160μg/ml), HPD (2.5μg/ml, 5μg/ml, 10μg/ml) and their combination dosages. 630nm light (total output 2W) was delivered to tumor cells at a constant fluence rate: 200mw/cm2 and a constant irradiated time period: 20 minutes. We set 3 groups (no photosensitizers or no irradiation or neither) to be the control groups. We used inversion microscopy to observe the morphological change of tumor cells and flow cytometry technology to detect the death or apoptosis of tumor cells during the experiment. Results: After irradiated with 630nm light on 20 minutes, S180 tumor cells incubated with the combination dosage of ALA 40μg/ml and HPD2.5μg/ml were induced highest rate of apoptosis. The rate of cells' early apoptosis was 2.54%, while the late apoptosis was 95.10% Conclusion: The combination dosage of ALA 40μg/ml and HPD2.5μg/ml (25% of constant dosage) used in the PDT treatment was the most adequate dosage on cytology.
Photodynamic therapy of urethral condylomata acuminata using topically 5-aminolevulinic acid
Xiuli Wang, Hongwei Wang, Haishan Wang, et al.
Background: Electrocoagulation and laser evaporation for urethral condylomata acuminata have high recurrence rates and can be associated with urethral malformations. Objective: To investigate the effect of photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) on urethral condylomata acuminata and to examine the histological changes in lesions of condylomata acuminata after ALA-PDT. Methods: One hundred and sixty-four urethral condylomata patients were given topical ALA followed by intraurethral PDT through a cylindrical fiber. Among the cases, 16 penile and vulval condylomatous lesions in 11 patients were treated with topical ALA-PDT at same time. After the treatment, biopsy specimens were collected from the 16 penile and vulval lesions. The histological changes were then evaluated by light microscope and electron microscope. Results: The complete response rate for urethral condylomata by topical ALA-PDT was 95.12% and the recurrence rate was 5.13% after 6 to 24 months follow-up. Keratinocytes in middle and upper layers of the epidermis with marked vacuolation and some necrocytosis were detected one and three hours after PDT. Necrosis in all layers of the epidermis was noted five hours after PDT by microscopy. In electron microscopy of kerationcytes, distinct ultrastructural abnormalities of mitochondrion, endoplasmic reticulum and membrane damage were observed. Apoptotic bodies were detected three hours after PDT and a large number of the keratinocytes exhibited necrosis five hours after PDT by electron microscope. Conclusions: Results suggests that topical ALA-PDT is a simple, effective, relatively safe, less recurrent and comparatively well tolerated treatment for urethral condylomata acuminata. The mechanisms might be that ALA-PDT could trigger apoptotic process and necrosis in the HPV infected keratinocytes.
Photodynamic therapy for implanted VX2 tumor in rabbit brains
Fei Li, Hua Feng, Jiangkai Lin, et al.
To evaluate the therapeutic effect and the safety of single photodynamic therapy (PDT) with hematoporphyrin derivative produced in China, 60 New Zealand adult rabbits with VX2 tumor implanted into the brain were divided randomly into non-PDT-group and PDT-group. 36 rabbits of the PDT-group were performed photodynamic therapy. The survival time, neurological deteriorations, intracranial pressure (ICP), histology, pathology, tumor volume and brain water content were measured. Other 12 rabbits were received hematoporphyrin derivative and light irradiation of the normal brain. The ICP, histology, pathology, and brain water content were measured. The result indicated that Simple PDT may elongate the average survival time of the rabbits with VX2 tumors significantly; kill tumor cells; cause transient brain edema and increase ICP, but it is safe to be used in treating brain tumor.
The metabolization of ALA taken orally and its effect on skin and tumors
Jing Zhu, Hui-Guo Zhang, Mei-Jue Zhang, et al.
Objective: Research on the metabolize of ALA (after take orally) on skin and tumor, to find the best dose and diagnostic time of ALA after take orally Methods: Measure the fluorescence spectra of tumor and skin with different dose of ALA take orally (20mg/kg, 40mg/kg, 60mg/kg, 80mg/kg, 100mg/kg) and different time after ALA take orally (1h, 2h, 4h, 6h, 8h, 10h, 12h, 24h, 48h) when irradiated by laser. By analyzing the spectrum of fluorescence with optical multi-channel analyzer (OMA), also the fluorescence intensity should be normalized. Result: The best ratio (Itumor/Inomal) of skin was obtained at 60mg/kg, of ALA take orally and 6-8h after ALA take orally Conclusion: Measure the fluorescence spectrum of tumor and skin by using optical multi-channel analyzer (OMA). The best dose was 60mg/kg of ALA take orally and the measure time was 6-8 hours after ALA taking orally.
The metabolic comparison of HPD in normal brain tissue and S180 sarcoma in brain
Yu Wang, Jing Zhu, Huiguo Zhang
Objective: Search The Metabolic Comparision of HPD in Normal Brain Tissue and S180 sarcoma in brain. Methods: Xe laser photoradiation of normal brain tissue and S180 sarcoma in brain to excite fluorescence was performed at different time after the injection of hematoporphyrin derivative (HpD) in normal rats and rats with S180 sarcoma of Brain. We analysed HPD fluorescence lifetime imaging (wavelength: 630 nm and 690 nm) of two rat team with OMA. Result: We concluded the peak intensity of HPD fluorescence fell obviously in normal brain three hours later after injection, while it still retained high HPD concentration in sarcoma of Brain. Conclusion: first-rank time the 4~5 hours after injection of HPD is first-rank time 0f PDT and photosensitive diagnose in sarcoma of Brain of rat.
Metabolism of oral ALA combined small dose HPD in the small rat glioma
Yu Wang, Jing Zhu, Hui-Guo Zhang, et al.
Objective: Research on the metabolism of oral ALA combined small dose HPD in the small rat glioma to find the optimal oral dose and diagnostic time for the ALA-photodynamic diagnosis and therapy of brain glioma. Methods: Measure the fluorescence spectra of tumor in the treatment groups and control group and of brain tissue of no-tumor group with different doses of ALA taken orally combined injected small dose HPD and different time before and after take ALA when irradiated by laser. We analyzed the spectrum of fluorescence of every groups with optical multichannel analyzer (OMA) and compared it each other. Result: The maximum ratio (Itumor/Inomal) of fluorescence was obtained at 60mg/kg of ALA taken orally and 6-8h after ALA taken. Conclusion: The optimal oral dose is 60mg/kg of ALA and the optimal measure time is 6-8 hours after ALA taken.
Photodynamic therapy of malignancy of skin with He-Ne laser
Jing Zhu, Hongmin Shi, Hui-Guo Zhang
Objective: Research on the photodynamic therapy of malignancy of skin with He-Ne Laser. Methods: 35 cases of skin malignancy were treated with photodynamic therapy. He-Ne laser with output power of 600 mW was used and hematoporphyrin derivative (HPD) was applied, at a dose of 5mg/kg of body. 15 patients received simple surface irradiation, 20 patients received both surface and insertion irradiation. 28 patients underwent treatment for one time, 7 patients twice. The 12 cases were basel cell carcinoma, 7 cases were squamous cell carcinoma, 4 cases were skin carcinoma in situ, 8 cases were skin Paget's disease, 1 case was Paget's disease accompanying adenoid carcinoma, 1 case malignant melanoma, 1 case red hypertrophic disease, 1 case recurrent perianal carcinoma deriving from rectum.
Dermatology and Plastic Surgery
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Analysis of related factor of pigment alteration after Q-switched laser treatment
Wei Zhang, Cai Xia Xu, Yang Feng Ding, et al.
To explore the related factors of pigment alteration after the Q-switched laser treatment. After the Q-switched laser treatment, the side effects in patients were observed, recorded and analyzed. The results showed that the incidence of pigment alteration is directly related to age (OR1=2.519, confidence interval 0.996-6.366; OR2=2.519, confidence interval 0.978-6.488; OR3=8.311, confidence interval 3.312-29.695). Besides, the pigment alteration is also correlated to the skin types, but not to gender, kind of diseases, parts of body, intensity of ultraviolet radiation, character of work, wavelength of laser and the energy of laser. Older patient is easier to have pigment alteration than younger patient. Pigment alteration may be obvious in a pigmented individual than a lightly pigmented individual.
Experimental study on port-wine stain treated by small dose HpD and variable pulsed 532nm laser
Meixiang Qin, Jing Zhu, Xiawen Yuan
To obtain a new therapy for port-wine stain (PWS) with good effect and few side effects, the Leghorn chicken combs chosen as the animal models and treated by small dose HpD and variable pulsed 532nm laser were evaluated clinically using four different scoring systems commonly used in previous publication. Result: It was shown significant difference among 5 groups (p<0.01), and the treatment groups have better effect than the control groups. There's also difference among the four treatment groups and the higher dose of HpD has better effect. In all groups the higher the fluency of laser was used, the better the effect produce. Conclusion: The results provide evidence that small dose HpD and variable pulsed 532nm laser can increase the efficacy of treatment in PWS. Increasing the fluency of laser and the dose of HpD can improve the efficacy.
The effectiveness of treatment of xanthelasma palpebrarum with ultrapulsed CO2 laser
Hongmin Shi, Mei-Jue Zhang, Jing Zhu
Objective: To observe the effectiveness of treatment of xanthelasma palpebrarum with ultrapulsed co2 laser. Methods: 36 patients of Xanthelasma Palpebrarum (78 periorbital xanthelasmas) were treated with ultrapulsed CO2 laser irradiating on lesions. Results: All lesions could be removed completely with a single laser treatment. After 1~10 months follow-up time, no visible scarring was observed. 4 patients (11.11%) developed a recurrence of xanthelasma. Conclusion: The ultrapulsed CO2 laser is an effective and safe therapeutic alternative to all the other surgical procedures.
Treatment of condylomata acuminata with Ho:YAG laser
Hongmin Shi, Jing Zhu, Mei-Jue Zhang
Objective: The purpose of this study to evaluate the effectiveness of Ho: YAG laser irradiation in treatment of condylomata acuminata. Methods: 1025 patients of condylomata acuminata, in which the lesions of 620 patients were interior of different lacuna, the lesions in 79 patients were huge (the diameter of lesion is over than 5cm), and 26 patients were pregnant, were treated with Ho:YAG laser (0.5-0.8J/pulse, 5-15 pulses/sec) to melt all the lesions. Results: All lesions in 1025 patients were removed after one laser treatment. The recrudescent and regenerative lesions could be removed completely after repeated treatment. No scarring and stricture on the peristome of the urethra was observed. No abortion, premature delivery and other syndrome were occurred among the total 26 pregnant patients. Conclusion: The technique of treatment of condylomata acuminata with Ho:YAG laser is an effective and safe therapeutics with the characteristic of better function of the homeostasis, shorter period of the concrescence and easy to operate.
Otorhinolaryngology
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The clinical application of laser in otorhinolaryngology
Guo Zhen Meng, Zhao-He Meng, Zhi Hua Zhang
Objective: The paper presented the current application of laser in Otolaryngology in our hospital. Methods: We have applied the carbon dioxide, the YAG, the He-Ne and the Ho:YAG lasers to coagulate or vaporize treated Otolaryngology disease. Results: After treatment, we have a satisfying result. Conclusion: The paper presented the current application of laser respectively in otology, rhinology and pharynolaryngology and some representative of the treated diseases. It also demonstrated that long-term effectiveness of some diseases, such as allergic rhinitis and laryngeal stenosis treated by laser was not satisfying and further studies were expected, laser excision of tonsile was only used in the cases which traditional tonsillectomy was not available. Therefore, to improve clinical laser application greatly, further more research works and cooprations between investors of laser instrument and surgeons of oto-laryngology were necessary. Theory and Clinics of laser application should be improved also.
Treatment for intranasal synechiae by CO2 laser under endoscopic visualization
Yunhai Feng, Shankai Yin
Objective To explore the feasibility and clinical value of treatment for intranasal synechiae by CO2 laser with reduce the incidence of complication in endoscopic sinus surgery. Methods A retrospective study was made of 31 cases treated for intranasal synechiae by CO2 laser. A CO2 laser was used to facilitate removed intranasal adhesion between the middle turbinate and the lateral nasal wall with minimal blood loss under endoscopic visualization. Results 31 cases were followed up beyond 24 months. The overall effective rate was 90.3%. 3 patients underwent a revision endoscopic procedure. Conclusions The method has many advantages such as clear operative field, safe and satisfactory. So it is a good way to treatment for intranasal synechiae.
ILLLI
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Advances in endonasal low intensity laser irradiation therapy
Jian-Ling Jiao, Timon Cheng-Yi Liu, Jiang Liu, et al.
Endonasal low intensity laser therapy (ELILT) began in China in 1998. Now in China it is widely applied to treat hyperlipidemia and brain diseases such as Alzheimer's disease, Parkinson's disease, insomnia, poststroke depression, intractable headache, ache in head or face, cerebral thrombosis, acute ischemic cerebrovascular disease, migraine, brain lesion and mild cognitive impairment. There are four pathways mediating EILILT, Yangming channel, autonomic nervous systems and blood cells. Two unhealth acupoints of Yangming channal inside nose might mediate the one as is low intensity laser acupuncture. Unbalance autonomic nervous systems might be modulated. Blood cells might mediate the one as is intravascular low intensity laser therapy. These three pathways are integrated in ELILT so that serum amyloid β protein, malformation rate of erythrocyte, CCK-8, the level of viscosity at lower shear rates and hematocrit, or serum lipid might decrease, and melanin production, SOD activity or β endorphin might increase after ELILT treatment. These results indicate ELILT might work, but it need to be verified by randomized placebo-controlled trial.
Influence of intravascular low level He-Ne laser irradiation on iNOS, total-NOS, and ET-1 in acute spinal cord-injured rabbits
Zhenchun Yin, Yinghai Dong, Jing Zhu
Objective To research the influence of intravascular low level Laser irradiation (ILLLI) on total NOS, iNOS, and ET-1 in spinal cord following acute spinal cord injury (ASCI), and discuss the protective effects of ILLLI on neurons. Methods 72 rabbits were randomly divided into 3 groups: treatment group, injury group and control group. In treatment group and injury group, after laminectomy at the level of T-13, ASCI was performed by using Allen's method with slight modification (6g×10cm) on rabbits. After injury, rabbits were treated immediately with He-Ne laser (power 5 mW, 1 hour per day for 10 days). At the day of 10th after treatment, total-NOS, iNOS, and ET-1 in spinal cord tissues were measured. Results The expression level of total-NOS, iNOS, and ET-1 in spinal cord in injury group were significantly higher than those in control group (P<0.05), while after ILLLI the level of these index in treatment group decreased statistically significantly compared with those in injury group (P<0.05). Conclusion ILLLI can significantly decrease the expression level of total-NOS, iNOS, and ET-1 in spinal cord. It indicates that ILLLI can relieve the overexpression of total-NOS, iNOS, and ET-1, and thus can perform protective effects on neurons in the course of secondary spinal cord injury (SSCI) following ASCI
The neuroprotective effects of intravascular low level laser irradiation on cerebral ischemia rats
Yongming Qiu, Zhaofeng Lu, Zhongguang Wang, et al.
The effects of intravascular low level laser irradiation of He-Ne on rat MCAo-induced cerebral injury were studied. The results showed that control rats (subjected to MCAo injury without laser treatment) at 7d exhibited striatal and cortical brain infarction in the right hemisphere from approximately 3 to 11mm from the front pole. the total infarct volume in this group was 34.5±8.1mm3. For experimental rats (with laser management), the total infarct volume was 29.0±9.0mm3. P was gained less than 0.05. The neurological score of control group was 4.7±0.6 and it was 5.2±1.0 in experimental group, comparison by statistical analysis showed P less than 0.05. The cerebral pathological damages in the control group were more severe than in experimental group. We concluded that the intravascular low level laser irradiation has no remarked complication and is helpful to reduce ischemic damage. There is clinically potential for the application of intravascular He-Ne low level laser irradiation in ischemia stroke.
The intravascular low level laser irradiation (ILLLI) in treatment of psoriasis clinically
Jing Zhu, Fan Nie, Hong-Min Shi
Objective: The title is research curative effect of intravascular low level laser irradiation (ILLLI) in treatment of psoriasis. Method: 478 patients with psoriasis from five groups to observe their efficacy. Group1 were treated by He-Ne laser combined with drug. Group 2 were treated by semi-conductor laser combined with drug. Group 3 were treated only by He-He laser. Group 4 were treated by semi-conductor laser. Group 5 were treated only by drug. The Ridit statistical analysis was applied to all of these data. The treatment of intravascular low level laser irradiation is as follow: laser power: 4-5mw, 1 hour per day and 10 days as a period combined with vit C 2.0 g iv and inhalation of O2. Results: The clinical results: the near efficient rate was 100%, in group 1-4, if combined with drugs it would be better. Ridit statistical analysis showed no significant difference between group1-4, p>0.05. The efficient rate 72.97% in group5.There were showed very significant difference with group1-4, p<0.01. 2.There were no significant differences between He-Ne laser (632.8nm) and semiconductor laser (650nm); 3.The efficacy of ILLLI in psoriasis was positive correlation to the ILLLI times. Conclusions: It can improve curative effect of intravascular low levellaser irradiation (ILLLI) in treatment of psoriasis.
The relativity between cytokines and psoriasis and the influence on its variation induced by ILLLI
Jing Zhu, Fan Nie, Xiawen Yuan, et al.
Objective: To explore the relativity between cytokines such as IL-8, TNF-α, VEGF and psoriasis and the influence on its variation by ILLLI. Methods: 47 patients with psoriasis were divided into 5 groups, treated with ILLLI (1h per day, a course of treatment is 10 days), observed the variation of IL-8, TNF-α and VEGF in peripheral blood of patients with psoriasis between pre and post treatment and compared with the control. Results: 1. In each case of psoriasis, the concentration of IL-8 in blood was significantly higher than that of control group. After treatment, the concentrations of A group, B group and C group were decreased significantly, which were close to the control. The related statistical analysis showed significant difference. Among them, A group decreased most significantly; Although there is no significant difference in concentration of IL-8 of D group and E group between pre and post treatment, the trend of them became to keep decreasing. In each case of psoriasis, the concentration of TNF-α in blood was much lower than that of control group. The concentration of TNF-α in A, C, D group increased significantly as compared with pre-irradiation except that in E group. In cases, the concentrations of VEGF in blood were much higher than that of control group. In each group, there was no difference in VEGF concentration between pre and post irradiation. Conclusions: The decrease of IL-8 induced by ILLLI might be related with its immunosuppressive function. It suppressed the activity of CD4+T cell which could secrete a great deal of IL-8 and play an important role to the tache of psoriasis onset. So in the psoriasis patients who were treated with ILLLI, the production of TNF-α could be suppressed. In patients, the increasing of VEGF might be related with the increasing of IL-8. There was no difference of it between pre and post ILLLI treatment might because VEGF was not the action target of ILLLI.
The effect of ILLLI on peripheral blood SOD,MDA in psoriasis treatment
Jing Zhu, Fan Ni
Objective: To research the effect of Intravascular low level laser irradiation (ILLLI) on the SOD,MDA in the treatment of psoriasis. Method: 47 patients suffering from psoriasis from five groups were treated by Intravascular low level laser irradiation (power: 4-5mw, 1h per day, period of treatment: 10 days). We checked the change of SOD,MDA peripheral blood in 10 normal people between pre and post treatment. Group A were treated by He-Ne laser combined with drug, group B were treated by semi-conductor laser combined with drug, group C were treated only by He-Ne laser, group D were treated only by semiconductor laser, group E were treated only by drug. Results: The levels of SOD in red cell of psoriatic patients from five groups after treatment were significantly lower than that of controlled group. The levels of SOD of them were significantly increased and nearly closed to that of controlled group; the levels of MDA in red cell of psoriatic patients from five groups after treatment were significantly higher than that of controlled group; the levels of MDA of them are decreased, however, they were still not recovered to normal levels. Conclusions: ILLLI, both He-Ne laser and semiconductor laser, can activate SOD in psoriasis patients and enhance their ability of anti-oxidation.
The effects of ILLLI on peripheral blood T lymphocytes subpopulation and NK cells in psoriasis treatment
Jing Zhu, Fan Ni
Objective: To research the effects of Intravascular low level laser irradiation (ILLLI) on the immulogic function of cells in treatment of psoriasis. Method: 49 patients suffered from psoriasis were treated by Intravascular low level laser irradiation (laser output power: 4-5mw, 1 hour per day, a course of treatment is 10 days). We checked the function of T lymphocyte subgroup and NK cell in peripheral blood between pre and post treatment. Results: 1. The mean value of CD3+ in post treatment is higher. P<0.05. Significant difference is showed between pre and post treatment. 2. The mean value of CD4+ in post treatment dropped slightly while the mean value of CD4/CD8, NK cell in post treatment increased little, nearly approach the mean value of natural person. 3. The mean value of CD4+,CD8+,NK cell which is under 30% increased the percent obviously after the treatment; The mean value of CD4+,CD8+ u higher than 30% obviously drop the percent, P≤0.05 and <0.01. Related statistical analysis showed significant and much significant difference between pre and post treatment. Conclusions: The low level laser irradiation (ILLLI) in treatment of psoriasis has bidirectional ajustive effect which can balance the immulogic function of cell.
Research of epidermal cellular vegetal cycle of intravascular low level laser irradiation in treatment of psoriasis
Jing Zhu, Xiaoqing Bao, Meijue Zhang
Objective: To research epidermal cellular vegetal cycle and the difference of DNA content between pre and post Intravascular Low Level Laser Irradiation treatment of psoriasis. Method: 15 patients suffered from psoriasis were treated by intravascular low level laser irradiation (output power: 4-5mw, 1 hour per day, a course of treatment is 10 days). We checked the different DNA content of epidermal cell between pre and post treatment of psoriasis and 8 natural human. Then the percentage of each phase among the whole cellular cycle was calculated and the statistical analysis was made. Results: The mean value of G1,S phase is obviously down while G2+M phase increased obviously. T test P<0.05. The related statistical analysis showed significant difference between pre and post treatments. Conclusions: The Intravascular Low Level Laser Irradiation (ILLLI) in treatment of psoriasis is effective according to the research of epidermal cellular vegetal cycle and the difference DNA content of Intravascular Low Level Laser Irradiation between pre and post treatment of psoriasis.
Effect of intravascular irradiation of He-Ne laser on cerebral infarction: hemorrheology and apoptosis
Jian Zhu, Min-yi Liang, Hao-cai Cao, et al.
Objective: To explore the efficacy of He-Ne laser intravascular irradiation on infarction and hemorrheology. To observe the effects of intravascular low level He-Ne laser irradiation (ILLLI) of blood on cell proliferation, apoptosis and chromosome in lymphocyte from cerebral infarction. Methods: Seventy cases with cerebral infarction were randomly divided into groups control group (35 cases) treated only with common drugs and therapeutic group (35 cases) treated besides common drugs also by He-Ne laser intravascular irradiation. Their hemorrheology index and treatment results were observed and compared. The blood lymphocytes of cerebral infarction were cultured before and after treatment. After that, the mitosis index (MI), cell kinetics index (CKI), sister-chromatid exchanges (SCE) frequencies and apoptosis were determined. Results: The therapeutic group was better than the control one. The effective rate in the therapeutic group was 88.6%, in the control one was 65.7%. The viscosity and fibrinogen, etc. were better than that in the control group with significant difference (P<0.01). The lymphocyte proliferation index was significantly two increased than the control one (P>0.05) in cerebral infarction patients after treatment; The CKI of lymphocytes had no obvious difference among groups (P>0.05); SCE frequencies of lymphocytes had no statistic significance between control group and ILLLI on (P>0.05). It showed the apoptosis rate of lymphocytes in cerebral infarction patients after ILLLI treatment increased significantly compared with the control group, (P<0.001). There was a significant difference of apoptosis rate of lymphocytes in cerebral infarction patients than the control (P<0.001). Conclusions: During the He-Ne laser intravascular irradiation of the cerebral infarction, the low level He-Ne by ILLLI can increase the proliferation of lymphocytes, and can induce lymphocytes to apoptosis, but has no mutagenicity of cells.
Ophthalmology
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Prophylactic use of timolol maleate to prevent intraocular pressure elevation after Nd-YAG laser posterior capsulotomy
Jiping Cai, Ruili Wei, Xiaoye Ma, et al.
Objective: To evaluate the effective prophylaxis of topical 0.5% timolol maleate for the intraocular pressure rise following Nd-YAG laser posterior capsulotomy. Subjects and Methods: One hundred and ninety eyes of 184 patients undergoing Nd-YAG laser posterior capsulotomy were randomly assigned to pretreatment with either topical 0.5% timolol maleate (therapy group) or nothing (control group). Results: The mean IOP of the therapy group was 14.8±3.0 mmHg before capsulotomy and 15.7±3.4 mmHg after capsulotomy (P>0.05), whereas 15.1±3.3 mmHg and 17.2±4.3 mmHg (P<0.05) of the control group. There was no statistically significant difference between the two groups with regard to mean IOP before capsulotomy (P>0.05), but statistically significant difference between two groups after capsulotomy (P<0.05). Six of 91 eyes (6.6%, 2 aphakias included) of the therapy group had an IOP elevation greater than 6 mmHg compared with 14 of 99 eyes (14.1%, 8 aphakias included) of the control group (P<0.01). Conclusion: The pretreatment with topical 0.5% timolol maleate is effective in preventing IOP elevation after Nd-YAG laser posterior capsulotomy.
Early panretinal photocoagulation for the treatment of ischemic central retinal vein occlusion
Zikui Yu, Naizhen He
Objective: To evaluate the safety and efficacy of treating ischemic central retinal vein occlusion (CRVO) with early panretinal photocoagulation (PRP). Methods: 24 eyes of 24 cases suffered from ischemic CRVO with history shorter than 3 months were included in this study. PRP treatments were completed through 3 to 5 times of laser therapy with total laser burns of 1000 to 2000 (mean 1505±384). Patients were followed up 3 months to 2 years, mean 18.4±8.0 months. The neovascularization regression and visual acuity were compared before and after PRP, also the long-term complications were observed. Results: 3 eyes of iris neovascularization (INV) regressed after PRP and there was no significant difference in visual acuity between prelaser and postlaser. No neovascular glaucoma (NVG) occurred and 2 eyes occurred vitreous hemorrhage during the follow up period. Conclusions: Early panretinal photocoagulation is safe and efficacious in preventing and reducing complications of ischemic CRVO. It can save valuable treatment time for some patients.
Surgery
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Laser application in the field of vascular anastomosis: experimental and clinical study
Masayoshi Okada
Nowadays, much attention has been paid to keep long-term patency after vascular anastomosis especially for small-caliber vessels in vascular surgery. From these standpoints, low energy CO2 laser was used to make an anastomosis especially for small-caliber vessels. And then an availability of vascular anastomosis by laser could be apparently recognized.
Laser angioplasty for cardiovascular disease
Masayoshi Okada
Recently, endovascular interventions such as balloon angioplasty, atherectomy and the stenting method, except for conventional surgery have been clinically employed for the patients with atheromatous plaques of the peripheral and the coronary arteries, because the number of patients with arteriosclerosis is now increasing in the worldwide. Among these procedures, restenoses after endovascular interventions have been remarkably disclosed in 20-40% of the patients who underwent percutaneous coronary interventions. Thus, there are still some problems in keeping long-term patency by means of endovascular techniques such as balloon angioplasty and atherectomy. For reduction of these problems, laser angioplasty using Argon laser was applied experimentally and clinically. Based on excellent experimental studies, laser was employed for 115 patients with stenotic, or obstructive lesions occluding more thasn 75% of the peripheral and the coronary arteries angiographycally.
Using transurethral Ho:YAG laser resection to treat urethral stricture and bladder neck contracture
Juanjie Bo, Shengguo Dai, Xuyuan Huang, et al.
Objective: Ho:YAG laser had been used to treat the common diseases of urinary system such as bladder cancer and benign prostatic hyperplasia in our hospital. This study is to assess the efficacy and safety of transurethral Ho:YAG-laser resection to treat the urethral stricture and bladder neck contracture. Methods: From May 1997 to August 2004, 26 cases of urethral stricture and 33 cases of bladder neck contracture were treated by transurethral Ho:YAG-laser resection. These patients were followed up at regular intervals after operation. The uroflow rate of these patients was detected before and one-month after operation. The blood loss and the energy consumption of holmium-laser during the operation as well as the complications and curative effect after operation were observed. Results: The therapeutic effects were considered successful, with less bleeding and no severe complications. The Qmax of one month postoperation increased obviously than that of preoperation. Of the 59 cases, restenosis appeared in 11 cases (19%) with the symptoms of dysuria and weak urinary stream in 3-24 months respectively. Conclusions: The Ho:YAG-laser demonstrated good effect to treat the obstructive diseases of lower urinary tract such as urethral stricture and bladder neck contracture. It was safe, minimal invasive and easy to operate.
Frequency-doubled dual-pulse FREDDY lithotripsy laser in the treatment of urinary tract calculi
Xuyuan Huang, Juanjie Bo, Bin Chen, et al.
Background and Purpose: The Frequency-Doubled Dual-Pulse Nd:YAG FREDDY laser is a short-pulsed, solid-state laser with wavelengths of 532 and 1064 nm that was developed for intracorporeal lithothripsy. This clinical study is designed to test its fragmentation efficiency in the treatment of urinary tract calculi. Patients and Methods: 500 urinary tract calculi treated in 194 female and 306 male patients with a mean age of 46 years. All patients were assessed one week post-op with a plain film of the kidneys, ureters and bladder. Stone-free rate and final outcome have been evaluated. Final outcome is defined as stone-free or residual fragments. Analysis has been made according to stone size, location and number of stones. The analgesia requirements during each treatment and complications have also been analyzed. Results: The overall stone-free rate for patients was 92.4%. The success rate for upper ureteral was 85.1% (126/148), while the rate for mid/lower was 95.3% (307/322). Bladder stone success rate 96.6% (29/30). Of all 38 incomplete fragmentations, 20 cases (4%) were treated with ESWL and 18 cases (3.6%) had open surgery. Neither fever nor pyonephrosis was reported. The average laser treatment time was 3.3 minutes and the average post-op hospitalization was 2.5 days. Conclusions: The FREDDY laser is an extremely efficient and safe minimally invasive lithotripsy treatment for urinary stones. It should be considered as an alternative treatment for urolithiasis.
Ho:YAG laser application in cerebellopontine angle tumor operation
Yaohua Pan, Yu Wang, Xiaoxiong Li, et al.
We reported 25 cases of cerebellopontine angle (CPA) tumor operation with Ho:YAG laser assistance during the operative procedure. We analysed the surgical effects of Ho:YAG laser, compare it with CO2, Nd:YAG, argon laser, and illustrated its features and parameters. We think that Ho:YAG laser can be used to ablate and vaporize the tumor efficiently in the operation of the CPA tumors whose vascular supply is abundant and the texture is very tough. It can be used to reduce the bleeding and cooperate to incise tumor in the operation and improve the curable effect of the surgery.
Rethinking of photodynamic therapy on cerebral glioma: the difficulty of necrotic tissue exclusion and its sequence
Yongming Qiu, Zhaofeng Lu, Zhe Liu, et al.
The photodynamic therapy of cerebral gliomas is one kind of adjunctive therapy after operative tumor removal. But it is not widely accepted until now. We report two cases of failure treatment in our totally consecutive ten patients treated with this method and analyse the cause of the poor outcome. Unlike the uninary system and digest system, the difficult of necrotic tumor or brain tissue exclusion in the brain is marked and resulted in poor result. Our view is that the problem of massive necrotic tumor tissue exclusion which is the wish of therapist and the key of achieving good result might limit the further application of photodynamic therapy on cerebral gliomas.
Treatment of lumbar disc herniation by percutaneous laser disc decompression (PLDD) and modified PLDD
Xiao fei Chi, Hong zhi Li, Ru zhou Wu, et al.
Objective: To study the micro-invasive operative method and to compare the effect of treatment of PLDD and modified PLDD for Lumbar Disc Herniation. Method: Vaporized part of the nucleus pulposus in single or multiple point after acupuncture into lumbar disc, to reach the purpose of the decompression of the lumbar disc. Result: Among the 19 cases of the regular PLDD group, the excellent and good rate was 63.2%, and among the 40 cases of the modified PLDD group, the excellent and good rate was 82.5%. Conclusion: The modified PLDD has good effect on the treatment for lumbar disc herniation.
Analysis on the effect of urethra caruncle treated by Ho:YAG laser
Meijue Zhang, Jing Zhu, Hongmin Shi
Objective: To observe the effect of Ho:YAG laser in treatment of urethra cauncle. Methods: The patients suffering from urethra cauncle were treated by Ho:YAG laser, the energy of per pulse is 0.5J. The frequency of pulse is 5~15Hz, and the average power of the laser is 2.5~7.5W. Results: Among the patients 188 cases of urethra cauncle were only cured for one time, twice for 12 cases. No stricture on the peristome of urethra or urethrovaginal fistula was observed. Conclusions: The technique of treatment of urethra cauncle with Ho:YAG laser is an effect and safe therapeutics with the merit of excellent homeostasis, improved visualization, minimal thermal damage to surrounding tissue, shorter period of recovery and easy to operate. It is better than CO2 laser and Nd:YAG laser.
The analysis on effect of oral mucoid cyst treated by Ho:YAG laser
Lin Zhou, Jing Zhou, Hongmin Shi
Objective: To observe the Effect of Oral Mucoid Cyst Treated by Ho:YAG Laser. Methods: The patients suffering from oral mucoid cyst were treated by Ho:YAG laser, which energy per pulse is 0.5j, pulse per second 5~15Hz, average power 2.5~7.5w. Result: Among all the patients were cured for one time. Conclusion: The technique of treatment of oral mucoid cyst with Ho:YAG laser is an effect and safe thearapeutics with the characteristics of excellent homeostasis, improved visualization, minimal thermal damage to surrounding tissue, shorter period of recovery and easy to operate. The total effect of Ho:YAG laser is better than CO2 laser and Nd:YAG laser.
Ureteropyeloscopy and holmium:YAG laser lithotripsy for treatment of ureteral calculi: report of 356 cases
Zhong Wu, Qiang Din, Hao-wen Jiang, et al.
Objective: To evaluate the efficacy and safety of holmium:YAG laser lithotripsy for the treatment of ureteral calculi. Methods: A total of 356 patients underwent ureteropyeloscopic lithotripsy using holmium:YAG laser with a semirigid uretesopyeloscope, 93 upper, 135 middle, and 128 lower ureteral stones were treated. Results: The overall successful fragmentation rate for all ureteral stones in a single session achieved 98% (349/356). The successful fragmentation rate stratified by stone location was 95% (88/93) in the upper ureter, 99% (134/135) in the mid ureter , and 99% (127/128) in the distal ureter. 12 cases with bilateral ureteral stones which caused acute renal failure and anuria were treated rapidly and effectively by the holmium:YAG laser lithotripsy. No complications such as perforation and severe trauma were encountered during the operations. 2weeks~17months (with an average of 6.8 month) follow up postoperatively revealed that the overall stone-free rate was 98% (343/349) and no ureteral stenosis was found. Conclusions: Holmium:YAG laser lithotripsy is a highly effective, minimally invasive and safe therapy for ureteral calculi. It is indicated as a first choice of treatment for patients with ureteral calculi, especially for the ones with mid-lower levels of ureteral calculi.
Improvement of the technique in treatment of internal hemorrhoids with Nd:YAG laser
Xiao-qing Bao, Jing Zhu, Hong-Min Shi
Objective: To observe and study the improvement of the technique in treatment of internal hemorrhoids with Nd:YAG laser and evaluate the effective rate. Methods: 60 patients of internal hemorrhoids were treated with Nd:YAG laser (10-15mw) irradiating on the mucosa of the lesions. Results: Among 60 patients, 57 patients were primarily cured with one treatment, 3 patients were primarily cured with two treatments. The effective rate was 95% with one treatment, and it reached to 100% with two treatments. Conclusions: the improvement of the technique in treatment of internal hemorrhoids with Nd:YAG laser is effective and easy to operate.
The clinical study of percutaneous disc decompression of treating herniation of cervical disc with Nd:YAG laser
Dianxue Zhang, Hefu Cheng, Jindong Wang
Objective: The possibility of PLDD (percutaneous laser disc decompression) and an ideal non-operative method which is long everlasting effect for PLDD was investigated. Methods: 159 patients of Cervical Disc Herniation with PLDD were studied. All the herniated discs were irradiated with 10-15J/S Nd:YAG laser quantum through optical-fiber under the supervision of C-arm X-ray. Results: All the patients were followed and reexamined CT or MRI after one to six months of PLDD. The result of cured (67.92%), excellent (24.53%), moderation (5.66%), non-effect (1.88%) was got. The excellent rate was 88.24%. The effective rate was 97.65%. Non-effective rate was 2.35%. Conclusion: When irradiated with Nd:YAG laser, the nucleus pulposus was vapouring, charring and coagulating. The volume and inner-pressure of the disc decreased. So the symptoms and signs improved. The main value of this methods were micro-damage, non-operation, no bleeding, no bone injury, good therapy effect, quick recovery, lesser pain, safety and excellent long everlasting effect. It is an ideal non-operative method of treating PLDD.