Laser trabeculoplasty (LPT) has been in clinical use for more than ten years, most of its studies were about argon laser LPT, in this study we aimed to evaluate the therapeutic effect of frequency-doubled Nd:YAG laser trabeculoplasty.

Two eyes of a rhesus monkey subject to frequency-doubled Nd:YAG laser LTP were examined by light and electron microscopy twenty-four hours and four weeks postoperatively. Light microscopy demonstrated trabecular meshwork edema, acute inflammatory changes such as the presence of polymorphonuclears and amorphous eosinphilous substance of the Schlemm's canal in the specimen 24 hours after surgery, otherwise, membrane-like extension over the surface of uveal meshwork was found in the tissue four weeks after surgery. Scanning electron microscopy of the specimens excited at earlier stage after irradiation revealed evidences of disruption, coalescence of the trabecular beams and the exudation of deformed erythrocytes among intertrabecular spaces; the specimens excited at later stage showed partial or total occlusion of intertrabecular spaces at laser burn site by a membrane like layer which probably originate from so called trabecular stem cell near the Schwalbe's line. Transmission electron microscopy of the tissue excited at 24 hours post laser showed necrosis of the trabecular cells, collagen fibrils edema, as well a macrophages and pigment cells among intertrabecular spaces; the tissues excited at 4 weeks post laser showed degenerated collagen fibrils and denuded collagen core without superficial trabecular cells.

To observe and analyze the refractive and complications of the LASIK for corrections of myopia. With the microlamellar keratoplasty and the excimer laser, LASIK was performed on 194 cases. According to the preoperative spherical equivalent refraction, divide the patients into three groups.

Q-switched neodymium-YAG laser iridectomy was performed in sixty eyes with pupillary-block angle closure glaucoma. Single pulse energy levels were more than 6mJ and multi-pulses were more than 4OmJ. The power settings consisted of a burst of 3 pulses (average). The curative successful rate by one to three times was I 00%. The authors advocated that iridectorny site was at middle-peripheral iris, energy level needed more high and lasing session was fewer. The cases have been made follow-up from three months to two years and were showed that the average ocular pressure was decreased l.llKpa (8.35rnmHg) and the vision of 56.7% eyes had obvious improvement, the others had no change. The curative effect was remarkable and no serious complications. KEY WORD: Nd: YAG Laser iridectomy

Intranasal Holmium:YAG laser dacryocystorhinostomy after failed external dacryocystorhinostomy were successfully performed in 6 patients. The inner wall of lacrymal sac is identified by the illumination of a fine fibroptic probe which is passed through the upper canaliculus and directed medially into the obstructed sac. The most bright spot as seen intranasally is marked as a target for laser penetration, using O.5-1J, 5-15w, 10-15 pulses/second. Through 400um quartz fiber delivery depending upon the consistency of the tissue. The new opening about 6mm in diameter is made with relative ease from inside of nasal cavity as the opening is only 40 42mm from the nostril. A silicone rod of 2 loops or 3 loops is introduced retrogradely into the lacrymal passage as a stent which should stay for 4 months or longer. Among the 6 patients, 5 cases were successful. The follow up period were 4-17 months after removal of silicone rods. One case was failed as the silicone rod was accidentally broken at 5 weeks after operation. The advantages of this operation are: avoidance of skin incision, deep sutures, bleeding and scarring.

There are 48 cases on the lower lid transconjunctival belpharoplastry with ultrapulse CO₂ laser produced by American Coherent Company. Compared the result, we concluded it is better to incise the tissue with the ultrapulse CO₂ laser than that with the continue-wave CO₂ laser. The former can prevent granulation tissue over growing in the wound and improve wound healing.

Since its first clinical practice in treating myopia in 1989, the application of excimer laser has developed a lot. Photorefractive Keratectomy has several advantages of stability, safety, etc. This operation treating myopia is widely practiced in clinic. Here, the authors reviewed their experience in 112 cases of the operation and the result of half a year follow-up.

The snoring disease is apt to give rise to the obstructive seep apnea syndrome. Its clinical feature is noisy stertorous breathing during sleeping, accompanied with frequency stoppages of breathing. As the sufferer is subjected to a state of chronic anoxemia during the night, he is liable to spiritlessness, obliviousness, and disordered sensibility in the day. Arrhythmia, hypertension, etc. may follow in severer case. We have obtained satisfactory therapeutic effects by laser palatopharyngoplasty on 20 cases of snoring disease for the period February 1992 - January 1996.

The recurrent nasal polyp complicated with nasosinusitis offer reflareacutely, and even form which various encranial and eye's compliances and lost smell are resulted. It is shown that the problem can cause the blocked breathes and bad sleeping of afflicted patients only if their nasal polyp was not completely cut out and relapsed into an action repeatedly. It is a goal procedure for ultrapulse CO₂ laser manufactured by Coherent Corp. Ltd. USA treating the problem. The machine gives out a great high power of pulse mode that destroyed precisely the polyp tissue by its vaporization. However, neither the continual laser nor the pulse laser does so easily. The selected cases included fiber persons with recurrent nasal polyp who were at the age range of 25-40 years old and took a different ill-period of 5-20 years long. They consisted of 3 cases for posterior rhinopolypus with bent nasoseta and 2 cases for median rhinopolypus. Majority of them experienced traditional operations of four times and at least for two times, but the relapse of rhinopolypus always adhere to them.

10 patients with vocal cord polyps treated by the Ho:YAG laser were reported with cure rate of 100 percent and no recurrence. The Ho:YAG laser vaporized the polyps tissue with non bleeding during operation, and mild postoperatively in vocal cord. The hoarseness caused by vocal cord edema would disappeared within one week. During one year of our follow-up, no residual or recurrent cases were found. All patients acquired hormonal voice quality.

A total of 420 cases of OSAS patients underwent laser- assisted uvlopalatoplasty (LAUP) with CO₂ and Ho:YAG laser, the follow-up period range 1-12 months in 360 cases. According to our overall response rate, total improvements in 60 percent of patients, significant improvement in 100 percent of patients. Except minor bleeding, no serious complications were observed, so LAUP should be considered as an alternative to UPPP.

The conventional way for the rhinopolypus operation is to use the polyp snare to cut polyp tissue. This method includes many weaknesses. (1) It often leads to polyp residue or even polyp recurrence when using polyp forceps deal with the part of polyp root. (2) Vaseline gauze is used in plugging nasal cavity resulting in an inconvenience of the patient. Since 1996, we have treated nasal polypus 42 cases by using Semi-conductor laser. There are advantages in the treatment: (1) Shortening operation time. (2) Cutting the root part of nasal polyp completely. (3) Resulting 83 percent cure rate. (4) Without plugging nasal cavity.

Previous therapies for port wine stains usually cause unacceptable scarring or obtain poor effect. Because port wine is a congenital vasculopathy consisting of an abnormal network of capillaries in the upper dermis with an overlying normal epidermis and the researchers found the tumor blood vessels were occluded accompanying the necrosis of the tumor after PDT. The author and his colleagues started a series of animal and clinical studies since 1991 about photodynamic therapy for port wine stain an they established the method of PDT for PWS. The clinical studies of over 1500 cases proved that PWS can be cured by PDT without scar formation because there is no thermal effect involved. No relapse was found within a maximum follow-up of six years.

There were one hundred Chinese cases treated with face laser resurfacing. Observed the result, the post-inflammatory hyperpigmentation was found in all case. It is not any use that the cases used the 3 percent hydroquinone before the operation. Eighty-five cases were going down between two and six months after the operation. Fifteen cases continued to nine months. Five cases continued to a year. Cosmetics are possible to affect the course of inflammatory hyperpigmentation. Hyperpigmentation disappeared more quickly while using 3 percent hydroquinone cream or KA cream after the operation. And intravenous injections with vitamin C is helpful.

Moles usually occur on the face and neck. Some occasionally have hairs growing.Most of them are benign tumors. We had treated 1612 cases of 4718 moles by applying CO₂ laser from laser year 1990-1996. Among them 4576 moles treated once were removed, accounting for 97 percent; 94 moles treated twice and 48 moles treated three times were removed, accounting for 2 percent and 1 percent respectively. After removal atrophic and neoplastic cicatrix occurred in 176 cases, for 3.7 percent and 39 cases, for 0.8 respectively. The patients with scar-inclined skin are not supposed to undertake the CO₂ laser treatment.

Repeated clinical intramuscular injection often cause buttock scleroma together with swelling pain scleroma, even more serious walking difficulty. Such cases not only bring great pain to the patients but also influence the original treatment. They are usually treated by hot compress but with no ideal effect. In the past few years 42 patients have been treated by Helium-Neon laser to be irradiated on intramuscular injection buttocks scleroma. The curative effect is satisfying. Now it is reported.

138 cases of skin vascular lesions were treated by variable pulse width green 532 nm. In the course of the therapy, the skin vascular lesions were divided into 3 kinds, spot vascular lesion, string vascular lesion, and even vascular lesion, then some specially designated laser therapeutic parameters were selected for each kind of lesion. In addition, the question of the cooling therapy was discussed also, and considered that it is very important that preventing over damaged to local tissue and avoiding skin pigmentation.

Ultrapulse carbon dioxide laser ablations of rabbit skin were investigated. Macroscopic, microscopic and electron microscopic appearances of the ablation sites were evaluated. Results showed that the effect of laser treatment was on the epidermis and the papillary dermis. All or some of the cell layers of epidermis were ablated degeneration took place in the papillary dermis. Wrinkles of the new epidermis were shallow and seldom. The new collagenous fibers were more elastic which made the skin tighter and few wrinkles. Results also demonstrated that ultrapulse carbon dioxide laser stimulated hairs to grow fast.

387 cases of various skin pigmentous diseases were treated by Versapulse 'C' laser in our department Versapulse 'C' laser consist of 4 kinds of laser with wavelength of VP532nm, Q532nrn, Q755nm, Q1064nm. The vascular lesions, prot wine strain, cherry angioma, strawberry nevus, perckles, solar lentigines, melasma and junctional moles were treated by VP532 or Q532 laser; the nevus of Ota and tattoo were treated by Q755 or Q1064 laser. Satisfactory results were obtained in this paper, we also discussed the therapeutic and the main points of varying diseases with varying laser of wavelength, the use of FMLA anesthesia, controlled cold therapy an the physical protection to laser.

Mainman developed the first ruby laser in 1960 and after 13 Kaplan successfully reported the use of CO₂ laser in the treatment of cervicitis. Soon after, Chinese gynecologists started to use the laser for diagnosis and therapy. It had been proved that more than 30 kinds of gynecological diseases could be treated effectively by laser. The remarkable laser treatment technique partially replaced with conventional methods used in that century. However, the application of laser had shown a broad prospect along with its further investigation.

In order to improve the diagnostic accuracy of malignant tumors with laser fluorescence, in 1996, our group successfully created the computerized laser fluorescence spectrograph type II with more reliable images shown overshadowing the naked eye method before 74 cases of female genital tract diseases had been examined by the LFS II resulting in 10 positive cases which were also proven pathologically as malignant tumors, without nay false negative, 3 cases presented suspicious positive but all were proven pathologically as non-tumors lesions, the false positive rate was 4 percent. Our work showed that the method of LFS II can provide a more rapid and accurate diagnosis for the clinical malignant tumors.

To study the selection of power, treating time, acting mode and safety of Nd:YAG laser in the procedure of endometrial ablation of the treatment of menorrhagia.

Meatal-hymenal deformity is a predisposing cause of the lower urological tract infection in females which is usually followed by sexual activity, menstruation or vaginitis. The urethral external orifice is usually narrowed owing to the deforming meatal-hymen. Morphologically, meatal-hymeneal deformity is classified into volcanic hymen and valvular hymen. Since May of 1985, 132 cases of meatal-hymenal deformity were treated with CO₂ laser at a wavelength of 10.6 micrometers and at an output power of 20 w. A wedge shape incision was made above the urethral external orifice accompanied by regional hymen vaporization at the bottom or on both side. Periodic expansion of urethra and lavation with 1/2000 bromo-geramine solution followed. The value of the method is simple in operation, without complication, not necessary to be in charge and with a satisfying healing rate of 97 percent. In this study, we discuss the pathological changes causing the lower urological tract infection in females, the operating methods, theory and advantages of CO₂ laser therapy.

Meatal-hymenal deformity is a predisposing cause of the lower urological tract infection in females which is usually followed by sexual activity, menstruation or vaginitis. The urethral external orifice is usually narrowed owing to the deforming meatal-hymen. Morphologically, meatal-hymenal deformity is classified into volcanic hymen and valvular hymen. Since May of 1985, 1 32 cases of meatal-hymenal deformity were treated with CO2 Laser at a wavelength of 10.6 urn and at an output power of 20 w. A wedgeshape incision was made above the urethral external orifice accompanied by regional hymen vaporization at the bottom or on both side. Periodic expansion of urethra and lavation with 1/2000 bromo-geramine solution followed. The value of the method is simple in operation, without complication, not necessary to be in charge and with a satisfying healing rate of 97%. In this study, we discuss the pathological changes causing the lower urological tract infection in females, the operating methods, theory and advantages of CO2 Laser therapy. Keywords: CO2 Laser; Meatal-hymenal deformit

Currently, wide applications of lasers in various disciplines of medicine including urology are well developed. A thorough knowledge of laser use in urinary tract disease is recommended. Low energy GA-LA-AS laser 904nm wavelength have been used to treat the peyronie's disease; CO2 and KTP-532 lasers have been used to treat premalignant and malignant squamous cell lesions of the penis; Nd:YAG, C02, Argon and KTP wavelengths have been used to treat ureteral stricture, ureteral stricture induced chordee; epilation of hair-bearing ureteral grafts; Ablation of posterior ureteral valves, ureteral tumors, ureteral caruncles, and ureteral condylomata accuminata have all been treated with good results. Ho:YAG laser transureteral incision of the prostate (TUIP) facilitates a bloodless TUIP, thus avoiding Catheterization. Laser prostatectomy with a TURPETTE: Nd:YAG laser was used to ablation of the prostate larger than 40g after basing combined with a limited TURP to facilitate the urinary flow recurring the swelling and shortening the duration of necrotic sloughs .Compare TURP with contact laser, interstitial laser finds TULIP in conclusion that TURP is still the gold standard in the treatment of BPH. The results of TULIP, contact laser and interstitial laser are about the same, but the time internals with in the patients become free of symptoms, however, vary widely. Holmium laser resection of the prostate: the technique of HOLRP produces a cavity identical in appearance to: Transureteral resection of the prostate. The-short-term results are excellent but longer-term follow-up is necessary. Nd:YAG laser coagulation prostatectomy: 3 years of experience with 227 patients. Complications included prostatitis in 2.6% of patients, ureteral stricture in 1 .8%, bladder neck stricture in .4.4%, and: reoperation for residual prostate tissue in 5.3%. Four hundred and eleven patients underwent HO:YAG laser resection of the prostate (HOLRP). Transureteral resection of the prostate using Ho:YAG laser produces early results equivalent to or better than those usually associated with electrosurgical TURP with a shorter hospital stay and a lower rate of complications.

28 cases of brain tumors were operated by SLT contact Nd:YAG laser from October 1995 to May 1997 in our hospital. Among these, 14 are menin-giomas, 5 are astrocytomas. Others are tumors such as acoustic neuromas, craniopharyngiomas, etc 21 cases underwent common craniotomy, 3, laser endoscopy operation; and 4, laser therapy under microscopy. Method of tumor resection: firstly, cutting and separating the tumor from brain tissues with GRP by 5-15w; secondly, vaporizing parenchyma of tumor with MTRL and sucking it, again, cutting and separating and so on, lastly removing the tumor entirely. The power of vaporization for glioma or tumors in ventricles is about 20-30w, but for meningiomas, 30-60w. MT was used on power of 15-20w to coagulate and homeostate the left cavity of tumor. According to our experience, laser operation can make bleeding reduced markedly, tumor resection become more thorough, and postoperative response and complications decrease obviously.

Common intraventricular operation often brings about some server complications such as high fever, lost of consciousness, stress ulcer and serious encephaledema etc. this is changing with the development of minimally invasive neurosurgery. SLT contact laser has advantages of little thermal effect, slight brain tissue injury and working normally in liquid environment. Endoscopy makes it possible that the operation can be carried out in tiny space. Combination of both techniques mentioned above leads to convenient removal of cerebral tumors in vital part of the brain like ventricle, thalamus and cerebellopontile angle et at. with little even without brian harm or no complications. The article reports three cases of patient of grain tumors in the third ventricle and thalamus and underwent such operations. It also discusses the indications of this kind of operation and presented the experience about this aspect.

The patients who suffer from upper digestive tract tumor, such as cancer of esophagus, cancer of cardia, all have serious obstruction and fail to get nutrition and can not bear the strike of the radiotherapy and chemotherapy. In order to reduce the obstruction symptom and suffering of the patients and to prolong their life time, since 1989, our hospital used the laser to cure the upper digestive tract tumor 11 cases with serious obstruction and got remarkable curative effect.

34 patients with advanced esophagus cancer and 8 cases of cancer of gastric cardia were treated by photodynamic therapy. The therapeutic effectiveness of the treatment was evaluated according the criteria used in China. CR 63.2 percent SR 11.3 percent, MR 2 percent. The total effective rate was 76.5 percent. There was no significant side effect in this group except mild skin photosensitization and pigmentation and exacerbation of pain in a few cases.

From May, 1994 to September, 1996 we have operated on 64 cases of brain tumor with Homium Laser, 18 cases of massive pituitary tumor with low energy laser were included. The result are satisfying. Now, we report it to the congress.

To access the early efficacy and safety of holmium laser resection of the prostate for the treatment of patients with symptomatic benign prostatic hyperplasia or with bladder calculi.

We report 5 cases of pulmonary disease treated with Holmium:YAG laser through fibrous bronchoscope. 1 inflammatory granuloma was cured after three times of treatment. Compared with conventional methods such as electrocautery and microwave treatment, laser has the merit of good hemostasis effect and quick recovery of the operation area. The other 4 patients who were suffered late lung cancer received 3-7 times of palliative treatment. After the treatment, the tumor tissues become smaller variably, and tact were unobstructed, symptoms of tract- obstructed obviously alleviated. We think that laser treatment has some practical significance in alleviating tract blocking of pulmonary diseases of late stage, and therefore raise the life quality.

Among tumors of urinary system, the morbidity of bladder cancer is the first one. It is multiple, also has high risk of regeneration. The paper reports that 679 bladder tumors in 108 patients had treated for 284 times by pulsed HO:YAG laser from July 1994-June 1997.

10 patients were treated by video-assisted-thoracoscopic surgery with laser in this article. No patient has complications of intrathoracic infection and air leakage of lung or died from the operation. Without opening the chest, it has less trauma as well as a better homeostatic effect. It is available for the patients who are old or have poor cardio-pulmonary function.

Intravascular low level He-Ne laser irradiation is a new therapy developed in recent years. In our hospital it was applied in the treatment and observation of 220 cases of schizophrenia, among which certain effect was achieved and about which the detail was collated and elaborated.

The study on irradiating in oral mucosa of rabbits with 650 nm diode laser and clinical application has been reported in this paper. The result of animal experiment showed: the obvious decrease of cholesterin and triglyceride has been found among those highly lipohemia rabbits in the experiments of 650nm diode laser irradiating accompanying with oxygen, as well as the parameters of hemorheology obviously being improved, as compared with highly lipohemia rabbits un-irradiating, the statistical analysis showing P < 0.01. In the meantime, the observation of histopathology shows, the lipide decreasing in aorta wall, intramyocardinal membranous layer,and renal interstitial in the group of rabbits which are irradiated with laser and accompanying with oxygen inspiration, and even the perfectly recovered tissue in some rabbits has been seen. This experimental result is significantly for clinical application. The results of clinic application showed, that the patients employed this method which treatment cerebral infarction, lipohemia, the total effective ratio achieved 91.7 percent, perfect effect 30.6 percent.

Intravascular Laser Irradiation on-Blo4d (ILIB) can heat many diseases. Up to date there have been many reports relative to this research area. Its major functions are 13 to increase the dissolving activation of fiber in blood and improve the blood theological properties, 2) to enhance the ability of carrying oxygen. But the micromechanism of ILIB with the function is still lack of the theory analysis, only some qualitative. Explanations and experimental reports are obtained. This article makes -a molecular-level theory analytical study on ILIB's functions mentioned above, in terms of quantum mechanics, quantum statistics, group theory and nonlinear science theory, along with considering die structure and function of protein and enzyme an blood.

We determined rheology in patients with cerebral infarction, before and after low-power He-Ne ILIB. The test covered whole blood viscosity red blood cell distortion index, platelet aggregation and D-dimer. The results shoed that low-power He-Ne ILIB results in non-significant decrease in whole blood viscosity, significant decrease in plasma viscosity, platelet aggregation and D-dimer and significant increase in RBC rheology index. This study suggests that He- He ILIB which may improve rheology and clinical symptoms of cerebral infarction patients is a simple, safe and effective therapy.

Liu TCY et al have put forward the biological information model on low intensity laser irradiation (BIML): low intensity laser irradiation couples with intracellular messenger through the chromophore absorption in the cell membrane: hot-color laser irradiation activates cAMP phosphodiestererase through G_i protein, or activates phosphoinositide phospholipase C through G protein, or activates one of receptor-associated kinases: cAMP; cold- color laser irradiation activates adenylate cyclase through G_s protein: cAMP$ARUP. In this paper, under the guidance of BIML, we applied the intravascular low intensity He-He laser irradiation on blood to a patient of idiopathic edema, and succeeded.

194 patients with psoriasis were treated by intravascular low level laser irradiation combined with Vit C 2.0g iv and O₂ inhale to the nose. An hour once a day, for 5-40 times, and 13.06 times in average, ten times with 4-7 days intervals. The results: cured 23 cases, good effected 61 cases, improved 110 cases, relapsed 10 cases. Curative effect was related to treatment times, cured and good effected 5 times 12.5 percent, 10 times 31 percent, 15 times 94 percent. A matched control group in 17 patients was treated by drug. The results: good effected 1 case, improved 13 cases, not effected 3 cases.

Intravascular Low Level He-Ne Laser Irradiation Therapy (ILLLI) is characterized by its considerable biologic and clinical effects. In our hospital, the therapy used to treat 149 patients with traumatic pain. 67 of which were cases with closed fractures; 49 cases with compound injures and postoperative pain; 23 cases with serious soft tissue injuries; 7 cases with traumatic pulmonary edema and 3 other cases. The pains were classified, according to the standards by the WHO, as Degree II of 60 cases and as Degree III of 89 cases. The therapeutic procedure is adopted as follows: Set the ILLLI therapeutic machine at 10 mw of output power with the laser probe inserted into the forearm vein. Each therapeutic course lasts 10 days with one therapy each day lasting 40 minutes. The outcome reveals that the local pain and swelling considerably decreased or disappeared after 9 times of the therapy for the 149 patients resulting in negative intaking of painkillers. The total effective rate counts to 100%, with 91 cases of significant effectiveness (61%) and 58cases of ensured effectiveness (39%). It can be concluded that the ILLLI therapy ensures a safe and reliable effectiveness, shortens the trauma healing process and the therapeutic period without any side effect. ILLLI may be considered a new method to treat traumatic pain. Key words: the Intravascular Low Level He-Ne Laser Irradiation therapy, traumatic pain.

With the background that ILLLI can lower the viscosity of blood, improve the microcirculation, we investigated and compared the therapeutic effect of conventional drug therapy and ILLLI combined drug therapy for brain trauma. We found that ILLLI combined drug therapy could effectively alleviate some symptoms such as headache, vertigo, nausea, vomiting, blurred vision, anorexia caused by brain trauma. the therapeutic effect of treated group was prior to control group.

Brain trauma is one of the main diseases that threaten human life. The modality of severe brain trauma reaches a level to 30-50%. The damage is even higher because brain trauma often occurs in young men. Highway accident and gun trauma resulted in high brain trauma in western countries, as well as in Chinese. Through decades of hard work, the modality of severe trauma decreased significantly, but the damage of neuron structure and function was still hard to recur. According to the degree, nerve function and psychia abnormal will occur at patients, especially in those with mild to moderate trauma. They are called post brain trauma syndrome which will last days to years, affecting human work and study, while drug therapy has little effects. ILLLI was a new technology originally used in former Soviet Union. With its simple structure, convenient manipulation and low price, ILLLI was used clinically in former Soviet Union and China [1]. Laser is transported through quartz fiber. Intravascular irradiation is carried out at superficial big veins, irradiating the blood circulation directly. Extra irradiation is carried out at the rich capillaries at mouth cavity. Parameters: power output: 3-5mw; irradiation time: 30-60mm. This method is developed rapidly in China, used widely in brain and heart vascular diseases, deafness, thrombotic vascularitis, chronic bronchitis, psoriosis. It is reported that laser irradiation can improve the symptoms resulted from brain trauma, such as headache, dizziness, amnesia, paralysis [2]. Nevertheless, the mechanism is studied little, and the systematic experimental-control study of the treatment of brain trauma is even less. In this study, brain trauma model rat was irradiated at the humeral vein by low level diode laser in vitro. The reaction of rat memory and brain free radical was observed and the significance and mechanism were discussed.

The ratio detection of laser-fluorescence has become an important detection instrument of diagnosis and localization for lung tumor because its high sensitivity. But since it refers to the ratio judged by the reflective light from tissue surface in the previous work, it causes very high background noise and affects the stability of ratio detection. In this paper, we have performed experiments to study the variation regularity between the reflective light of tissue and autofluorescence of tissue and cause background noise of lung tissue in vitro. Based on the se experiments, we have developed the instrument of ratio detection which using the green autofluorescence instead of the reflective light of tissue for the ratio. The new system of ratio detection have the advantage of low background noise, thus it can effectively eliminate the false positive results for diagnosis and localization of lung tumor in clinic practice.

To understand better the optical characteristics of normal and carcinomatous lung tissues in the clinical photodynamic diagnosis and light dosimetry, we measured the effective attenuation coefficient (mu) _eff, absorption coefficient (mu) _s and reduced scattering coefficient at 406.7-415.4 nm. We performed the measurements by using 'Depthometer with Isotropic Fiber-optic Probe' developed by ourselves accurately to measure the fluence rate distributions in the fresh samples during irradiation with a collimated broad beam of a violet Kr⁺ laser. The total diffuse reflectance R_d was also measured by using a flat-cut optical fiber to guide the light into a detector. Some conclusions of adding-doubling method as well as diffusion theory were utilized to derive the optical properties of the measured tissue. The optical penetration depths of normal and adeno-squamous carcinoma human lung tissues are 0.08 mm and 0.32 mm respectively. We believe that it is the first set of data of 6 at 4.6.7-415.4 nm for fresh human lung tissue.

Our study shows that the blood components are different in absorption spectrum and the wavelength of their peak absorption are various. However, all the absorption maxima are within UV wavelength range, and all the absorbencies fall gradually to the minima within IR range. And the same sort of blood component of human and rabbit bear many similarities in absorption spectrum. These findings will provide scientific bases for the blood laser irradiation use at optimal wavelength in treatment of human diseases and rabbit experiments.

OMA-III system is used to detect the change of human blood fluorescence spectrum affected by 632.8nm He-Ne laser. The result shows: 3 peaks emerge in this spectrum at near 670nm, 730nm, and 981nm for different types of blood. Within the limits, fluorescence intensity changes linearly with laser power. The fluorescence intensities at the spots of the three peaks decrease with time lasting, and become stable 8 minutes laser. During laser irradiating, the positions of three peaks shift differently for different types of blood. However, there is competition between the peaks of 670nm and 730nm at the same time.

Both the chemical mechanisms of photodynamic therapy (PDT) with new photosensitizer phthalocyanine (PC) and the relationship between the chemical mechanisms and the pathologic mechanism in PDT with PC (PC PDT) are not exactly clear. In this study, the mechanisms of PC-PDT in vitro and in vivo were aimed with research methods of ultrastructural cytochemical cerium deposition locations, EDX technique and apoptosis detection. Three kinds of PCs, disulfonated chloroaluminium PC, AlS₃PC and disulfonated zinc PC, were adopted in the experiments. The result revealed: (1) There are a direct proportion between the amount of the ¹O₂ enhancer and the amount of cerium deposition and an inverse ratio between the amount of the ¹O₂ quencher and the deposition. So the dominant mechanism of PC-PDT is ¹O₂; (2) The ultrastructural sties of most obvious pathologic damage ar the sites of richness in PC and the sites of richness in cerium deposition; the mitochondria is one of the most important PDT targets in tumor cells, and secondly other cytomembrane structures are also important sites injured by PC-PDT; both the PDT damages to tumor cells and that to microvasculature are the significant pathologic mechanisms for killing tumor cells in vivo; (3) Apoptosis is an event in the tumor killing process of PC-PDT.

There are differences in molecular structure between cancer, ulcer and normal tissue. They have their own specific absorb structures, which result in the highly specificity in the absorption of radiation. When laser light with specific wavelength irradiates on cancer or normal tissue, the inherent fluorescence of them can be stimulated. With the help of specific instrument, the curve of spectrum can be drawn. The various fluorescence peak value of cancerous and normal tissue can be used to differentiate between the two. The instruments used include some kinds of the most advanced technologies in nowadays, such as current laser, photoelectron, computer, microptic rapid spectrum analysis.

Hematoporphyrin derivative (HPD) can selectively accumulated in cancerous tissues. Illuminated by a certain wavelength of light, it will emit a red fluorescence which has peaks at 630nm and 690nm. With this character HPD is used to detect and localize malignant tumors. A spectroscopic instrument, optical multichannel analyzer (OMA) recorded the shape and the intensities of the fluorescence. A 580nm filter was used to block any scattered excitation light. HPD has its adverse effect named cutaneous phototoxicity which produces erythema, edema, and more seriously, blistering due to its high concentration in skin. In our experiment, we divided 60 Kunming mice with s-180 sarcoma to three groups. Two groups were injected a small dose, 2mg/kg and normal dose, 5mg/kg of HPD, respectively. The third group were left intact. Referring to the standard curve of HPD previously recorded, we could tell where the cancerous tissues were according to the spectrographs. This method detected 22/30(73%), 10/13(77%), and 1/14(7%) of tumors in groupi (2mg/kg), group2 (5mg/kg) and group3 (no HPD), respectively. Results of Chi-test showed no distinct differences between two HPD injected groups (p<O.O5). The fluorescence intensities of normal and cancerous tissues were studied and we found that the intensity ratios of cancerous tissues to normal tissues varied among the three groups. In group 1 and group2 they were 2.22±1 .59and 1.97±1.42 and t-test proved that distinct differences existed to the value 1.09±0.45 of group3. It seemed that in the cases of either injected with normal dose or small dose of HPD, the intensities of cancerous tissues will rise to a certain degree that much higher than that without injection. Keywords: laser, fluorescence, diagnosis

Laser induced fluorescence technique is a convienient, non-traumatic and high sensitive mehtod for tumor detection. The principle is that photosensitizers such as hematoporphyrin derivtives (HpD) has a special affinity to cancerous tissues. Being injected hematoporphyrin and excited with laser of a certain wavelength, cancerous tissues have characteristic fluorescentic peaks near 630 nm and 690 nm, while no such peaks have been observed in normal tissues. So it can be applied to tumor diagnosis. In this paper, we report small dosage of hematoporphyrin is applied to photosensitive diagnosis and the establishment of laser-induced fluorescence detection system with optical multichannel analysis (OMA) as it core. The LIF system is composed of three parts: 1 . fluorescence excitation and reception including laser machine as the exciting resource, exciting and recepting part and the corresponding light path coupling system. 2. photo-electricity transformation including OMA 4 system, electricity resource, cooling device, multi-color device with three gratings, and the multi-color device monitor. 3. computer signals handling including computer (Gateway 2000, 486 DX2/66). Control band connecting computer with OMA, printer, spectrum analysis and data transformation software. This paper introduced the system structure, regulaiton and operation methods in detail. Among them, the establishment of an excellent light path system, especially the good coupling between the exciting part (laser machine) and the recepting part (OMA) is the key to success .We have exprimented three kinds of fibers: coaxial fiber, parallel fiber and monofilament fiber. After comparing their advantages, disadvantages and working ways, we choose two pieces of paralled fibers (600nm) used to diagnosis of intralumatic tumors in clinic. Development of manofilament fiber is being carried out, too, The appropriate choice o flaser machine also has a great influuence to the exciting efeciency. Pratice has indicated that this system has high sensitivity and wide dynamic range. It is easy to operate the programme with menu can greatly improve the effeciency. With fiber, it can be applied to detect both superficial and intralumatic tumors. Complicated data handling also can be carried out with the advanced spectrum analysis programme. From our experimental and clinical reults, we believe this system has atained primary requirements on designment and clinic. In order to increase the sensitivity and reduce the sufferings of patients. Improvement of this system is necessary.

It is a new physical diagnostic technology to identify tumor by using laser-induced fluorescence. The fundamental is that porphyrins can accumulate i tumor because of their specific affinity to tumor tissues. However the concentration in normal tissue is very low. Being excited by some light with special wavelength, porphyrins can emit red fluorescence, whose peak wavelength is at 630nm and 690nm. The difference of fluorescence intensity between tumor and normal tissue can indicate where tumor is located. After injecting exogenic porphyrin to the patient, we can differentiate tumor from normal tissue by analyzing fluorescence of an organ. Hematoporphyrin derivative (HPD) has been used to diagnose and treat different tumors for a long time [1 ,2.Itis well known that when examined with endoscope, the early tumor in bronchial gastrointestinal and urinary tract, being very small, can't be easily diagnosed. After HPD being injected into the patient, the tumor will emit red fluorescence when irradiated by laser. By analyzing the spectrum of fluorescence with optical mutichannel analyzer (OMA), we can indicate the location of tumor and sample the tissue for biopsy. So the diagnostic accuracy is enhanced. The clinical suggested dose of HPD is 5mg/kg. Photosensitivity reaction is the main side effect of HPD. When patient who has been injected with HPD irradiated by sunlight, erythematous vesicles may occur on the his skin [3]. To avoid the side effect, the patient has to be protected from powerful light for about a month. It is annoying matter to patient. If photosensitivity drug isn't used, the demand to exciting light is very strict because the autofluorescence emitted by tumor tissue is faint. In order to diagnosing tumor, we have intravenously injected small dose of HPD into patients and analyzed the fluorescence with OMA. The time that patients have to be protected from powerful light was reduced from a month to three days. Meanwhile, the demand of exciting light was cut down. So we can outmostly use the instrument now available. Because experiment on animal had showed that small dose of HPD (2mg/kg) can do favor to diagnosing cancer and there isn't statistical difference between the diagnostic accuracy of small dose and that of larger dose, we gave patients the dose of 2mg/kg.

Laser has widely been used in life science. Laser technique is changing the face of microscopy. For the first time, it offers biologists to produce three dimensional images of the insides of cells. Laser microbeam used as a micromanipulator has become a good tool for cell fusion, gene conversion and chromosomal manipulation. Flow cytometry that composed of laser and computer technique used to quantify cells component and morphology. It has been become the basic of analytical cytology. Now, laser technique is going to used to expose the secrets of human life, to sequence DNA with high speed. This paper will introduce laser applied in cell biology and molecular biology.

Objective: To determine the effect of these materials of cell culture on transmittance. Methods: An UV spectrophotometry was used to detect the transmittance laws of cell well, wall of culture flask and culture solution and the absorption laws of photosensitized. Results: These transmittance of cell well cover and the wall of culture flask were more nearly 100 percent and the transmission valley in 575 nm being caused by phenol red. The transmittance was hardly influenced by the D-Hanks solution between 200-800nm. Conclusion: This dosimetry of laser irradiation on cultured cell is scientific and accurate.

The comparative study of sciatic nerve microepincutral anastomoses with Ar⁺ laser and conventional suture techniques was made on rats. Total tests included electrophysiological and histopathological studies. The result of the experiment showed that nerve welding with laser is better than conventional suture techniques.

In order to achieve a better long-term patency result and solve the problem of tensile strength in laser artery anastomoses, diode laser and Indocyanine Green (ICG) enhanced albumin were applied to medium-size artery anastomoses with three different methods, that is, direct laser vascular anastomoses, direct method enforced with ICG albumin, and laser welding with ICG albumin as 'solder'. Internal mammary artery (IMA) harvested from patients undergoing coronary bypass procedures, in vivo rat abdominal artery, and in vitro swine heart and IMA were chosen as the experimental materials. The results revealed that only 3.15 +/- 0.36 minutes were required for each anastomosis; the bursting pressure and tensile strength were greater in the groups enforced with ICG albumin and laser welding than that with direct laser anastomoses. In the laser soldering group, the thermal damage was limited in the adventitial layer, only at a depth of 200 micrometers . There was also a satisfied result in the in vivo laser welding rat's abdominal adventitial layer, only at a depth of 200 micrometers . There was also a satisfied result in the in vivo laser welding rat's abdominal arteries. However, end-to-side laser welding of IMA soronary artery with ICG albumin needs further investigation about its tensile strength in an in vivo model.

Liu TCY et a! (SPIE 2887, pp. 140-15 1, 1996) have put forward the biological information model on low intensity laser irradiation (BIML). Low intensity laser irradiation couples with intracellular messenger through the chromophore absorption in the cell membrane: hot-color (red, orange, yellow) laser irradiation activates cAMP phosphodiesterase through G, protein or activates phosphoinositide phospholipase C (PLC) through Gq protein, or activates one of receptor-associated kinases: cAMPL; cold-color (green, blue, violet) laser irradiation activates adenylate cyclase through G, protein: cAMP'l'. In this paper, we applied BIML to studying the direct effects of laser irradiation on cells in photodynamic therapy. It was concluded that cold color laser irradiation PDT is better than hot color laser irradiation PDT from the viewpoint of the effects on cells and the short term effects on cancer, but hot color laser irradiation PDT is superior to cold color laser irradiation PDT with respect to the long term effects on cancer. Key Words: photodynamic therapy; cancer; transmemberane signal transduction

The purpose of this study is to explore the significance of photodynamic activation of platelets in the mechanism of photodynamic destruction of tumors. Normal rats were divided into control and experimental groups, 6 rats in each group. Hematoporphyrin derivative was given in a dose of 10 or 20 mg/kg iv. Blood was taken and plasma rich in platelets was obtained by centrifugation. HeNe laser irradiation of the platelets in plasma was performed ex vivo at 30 mW, spot diameter of 6 mm for 16 or 32 minutes (100 or 200 J/cm2). Aspirin was given in one group in a dose of20 mg/kg p.o.at 24 and 3hrs prior to irradiation, while indomethacin was given in another group in a dose of 0.5 mg/kg. The mean± standard diviation of TXB2 and 6-keto-PGF-lcxconcentration in the plasma, and the TXB2/6-keto-PGF-la ratio were calculated for each group and compared statistically between groups by Student's t-test. The results showed that the TXA2 release was tending to increase and TXB2/6-keto-PGF-la ratio was significantly increased after PDT treatment in a dose-response relationship. Our findings evidently support that platelet activation may play an important role in the mechanism of microvascular damage, intravascular clotting and microcirculatory disturbance induced by photodynamic therapy. Indomethacin showed a more strong inhibitory effect on this process than aspirin did. It indicates that in patients taking indomethacin or aspirin, photodynamic therapy should be performed a few day after stopping those drugs. Key words: Photodynamic therapy, Platelets, Thromboxanes, Prostacyclins

The functional near-IR imager is made of 9 light sources and 4 pairs detectors. Each pair detector was filtered by two wavelengths. The light sources are controlled by a computer and the signals from the detectors are filtered, converted and processed by the computer. Functional near IR imager could resolve the brain activity temporally and spatially. The spatial resolution is determined by the detection structure and the temporal resolution is determined by the light sources and signal conversion time.

Solid brain models with a brain-like background have been constructed and tested by a near IR phased array optical system. Two different kinds of detection geometry, remission and transmission, have been tested on brain models. These two kinds of geometry scan different area of the brain mode and both have a good deductibility in the detection area. A 6 mm absorber can be detected and the absorber position can be localized through a significant change in relative phase.

In recent years, the effect of ultrasound (US) in combination with porphyrins such as a gallium-porphyrin complex (ATX-70) has been reported in the treatment of experimental cancers. Before clinical application of this method, further studies are needed. The transplanted squamous cell carcinomas (5CC) on C3H/He mice were irradiated by a tunable optical parametric oscillator (OPO) laser light or ultrasound, in the presence of several different photosensitizers. The tumor size and survival of mice after treatment were observed. Furthermore, we compared antitumor effects of combined irradiation of laser light and ultrasound with those of single laser light or ultrasound, in the presence of ATX-70 or a pheoforbide derivative (PH-1126). Besides PH-i 126 and ATX-70, the following sensitizers were tested: Photofrin II (Pf-II), hematoporphyrin oligomer (HpO). 5-aminolevulinic acid (5-ALA) and aluminum phthalocyanine tetrasuiphonate (AIPcS4). In the results, it was good effects of antitumor by the laser light treatment in the case of PH-1126 and AIPcS4, ATX-70, HpO nsd AIPcS4 produced betterantitumor effeets by irradiation with ultrasound. The antitumor effects of combined use of laser fight and ultrasound were stronger than those of single laser light or ultrasound in both cases of PH-i 126 and ATX-70. Key words: OPO laser light, ultrasound, PH-1126. ATX-70

In order to estimate the best concentrations of two photosensitizers and the dos of laser each lights for the anti-tumor effect of these photochemical combined treaments. We examined of anti-tumor effect of the photocheical treatment by optical parametric oscillator (OPO) laser lights with two photosensitizers administrations for the transplanted tumor of a cultivated murine leukemia (L5 178Y) cells to Balb/c mude mouse because there is an advantageousness of tunable wavelengths in the OPO laser. Different two photosensitizers of a 2.5ig/gbw pheophorbide-a derivative (PH-1126) and 1mM 5-aminolevulinic acid (5-ALA) as a protoporphyrin IX (Pp-IX) precursor were used when both sensitizers were administrated together. The tumor sizes, the survival fraction and the tumor histological changes of the nude mice were observed after the treatments. From those results, it was found that (1) it was observed the anti-tumor effect by PH-1126 also in the case of the single irrdiation at even 630nm of 5-ALA absorption peak, (2) the combined irradiations at 630nm and 6SOmn for the double administrations were obtained the best anti-tumor effect of the deepened necrosis and pyknosis or disappear-changes of nuclear of the tumor cells about 1 -1.5cm at the depth 1 weak after the laser treatments comparing that of the single treatment for the single photosensitizer. Key words:OPO-laser, two different wavelength irradiations, two different photosensitizers, anti-tumor effect of L5178Y, growth curve, survival fraction