There were many claims of extraordinary possibilities for laser surgery by the early gynecologic laser surgeons. They promised that by using the laser there would be increased speed of the operation, decreased blood loss, decreased infection rates, decreased thermal damage and finally increased clinical results. Despite this `hype,' our clinical experience over the last decade has demonstrated in a large part that the clinical results using the laser are equivalent to those using either sharp scalpel or electrocautery. It appears that the skill of the surgeon is a far more important variable than the type of instrument used by the surgeon. As a result, since 1990, the laser has begun to fall out of favor with gynecologists and, more recently, general surgeons. The gynecologic surgeon of the 1990s is now exploring the use of intra-abdominal endoscopically delivered sutures and staples as well as electrocautery. Considering the increased expense associated with lasers, it is likely that a gynecologic surgeon will continue to explore non-laser options in the future. With planning and cooperation and consultation between clinicians, basic scientists and industry, lasers may ultimately play an even more significant role than they have in the 1980s.

To evaluate the feasibility of using laser energy in fallopian tube reconstruction, laser assisted anastomosis of dog uterine horn was performed under general anesthesia and compared to conventional suture technique on the contralateral side. Similar degrees of external tissue adhesion were found. However, on the laser sides smoother scars, uniform mucosal surfaces, and significantly less stricture were noted. Histological evaluation also demonstrated the superiority of laser assisted anastomosis as compared to the conventional suture technique. These results suggest that laser assisted anastomosis with a thermal activated binding compound would be a superior method for fallopian tube reconstruction providing better healing of the mucosal surface and significantly less tubal stricture.

Laser beams are routinely used in the clinical practice of assisted reproduction. The main applications are in laparoscopic and hysteroscopic surgery. The potential applications of laser microbeams as a tool for gamete manipulations are studied and basic concepts are discussed.

In this chapter, we will try to classify the different indications of surgery and/or combined (medico-surgical) therapy in 1) peritoneal endometriosis 2) ovarian endometriosis 3) deep-infiltrating endometriosis of the recto-vaginal septum 4) ureteral endometriosis 5) digestive endometriosis

Potential applications of photodynamic therapy for endometrial disease are discussed. Experimental models that may lead to diagnosis and treatment of endometriosis as well as selective endometrial ablation are summarized.

We studied the effects of the very low-power Gallium-Arsenic infrared semiconductor laser and low-power Helium-Neon laser irradiation, single or in combination, compared to the placebo and conventional therapy on the recovery of 118 female patients from our hospital with the diagnosis of chronic pelvic inflammatory disorders. Laser biostimulation therapy proved to be significantly more efficient as compared with placebo or conventional therapy. The most efficient of all kinds of irradiations was the combination between He-Ne and Ga-As (laserpuncture and scanning). After laser treatments we didn't find any significant local genital changes both at the bimanual examination (except provoked pain), and at the echographical examination. Soft and very low-power laser therapy can be a useful alternative to the conventional treatments for pelvic inflammatory diseases.

The properties of surgical Nd:YAG laser (1.06 micrometers and 1.36 micrometers wavelength) with endoscopic fiber have been investigated. The possibilities of using it as a scalpel and as a coagulator suitable for the endoscopic gynecological operations have been established. The tissues of myometrium, endometrium and ovary have been treated with different output profile quartz fibers. The most efficient wavelength of laser light and the profile of fiber for cutting and coagulation of different structure tissue have been found.

Preliminary results of a randomized study comparing laser ablation of the prostate (LAP) to transurethral resection of the prostate (TURP) for the treatment of symptomatic benign prostatic hyperplasia are reviewed. Forty-five men enrolled in the study had a minimum 6 week followup. Preoperative AUA symptom scores, peak urinary flow rates, and post-void residual urines (PVR) were compared to postoperative values. The TURP group (22 men) did better than its LAP cohort (23 men) with a mean decrease in symptom score of 70% versus 47%, a mean increase in flow rate of 83% versus 53%, and a mean decrease in PVR of 51% versus 28%, respectively, at 12 weeks. LAP patients had less complications associated with impotence and retrograde ejaculation, required urethral catheters for less time, and had shorter hospital stays. With the development of more durable and reflective fibers the difference in efficacy between TURP and LAP should diminish while the benefits of LAP are preserved.

A 600 micron quartz fiber with a gold plated reflecting tip called Urolase^R (C.R. BARD, Inc., 8195 Industrial Boulevard, Covington, Georgia 30209), was used through a 21 French cystoscope to study the clinical outcome of patients undergoing Visual Laser Ablation of the Prostate (VLAP). The results of this prospective randomized trial comparing VLAP to TURP were studied in 32 patients with a nine month follow-up. TURP was carried out in the routine manner. VLAP was performed using the 12, 3, 6, and 9 o'clock lasing in the prostate. The 12 and 6 o'clock positions underwent lasing with 40 watts for 30 seconds while the 3 and 9 o'clock positions were lased with 40 watts for 60 seconds. If the prostate was greater than 4 cm in length from bladder neck to verumontanum, two around-the-clock lasings were performed, one near the bladder neck, the second near the verumontanum. Patients were evaluated comparing the AUA-6 Symptom Score, post-void residual urines, and peak voiding flow rates. The 32 prospectively randomized patients were evaluated at 9 months.

Transurethral ultrasound-guided laser induced prostatectomy (TULIP) is a recent development in the treatment of benign prostatic hyperplasia. The system is based upon Nd:YAG laser irradiation delivered by a right angled fiber. The dosimetry used in a clinical situation is mostly based upon animal studies. In this study, the light and temperature distribution in the prostate during Nd:YAG laser irradiation were modeled using Monte Carlo and finite differences theory. The results of this model were compared with in vitro experiments. The influence of the different parameters involved, e.g., the scanning speed and the power of the laser beam, were evaluated. Initial results show the temperature distribution and thus the therapeutic effect of the TULIP procedure. Until now 36 patients have been treated successfully. The mean in-hospital time was somewhat shorter than for a TURP treatment while the results were comparable. These treatments, however, show the need for a better understanding of the mechanisms involved. Modeling and subsequent in vitro and in vivo measurements might improve the understanding and safe and successful application of prostate treatment using laser based systems.

During the last three years more than 350 patients have been referred to our department for Benign Prostatic Hyperplasia. In spite of a palpably normal prostate, with no evidence or suspect of neoplasm, all the patients were evaluated with the blood determination of prostatic specific antigen (PSA) and transrectal ultrasound of the prostate (TUSP). Multiple staging biopsies of the prostate and imaging techniques evidenced neither capsule infiltration nor metastatic disease. Because of the site of the tumor (nonperipherical zone) and its stage (T1 stage) in the latter 11 patients a transurethral resection of the prostate (TURP) followed by a laser irradiation was planned. In order to establish the tumor staging, a lymph node dissection (in the last year by laparoscopic lymphadenectomy) was carried out before the procedure. Six weeks after an enlarged TURP, a laser irradiation of the residual prostatic tissue was performed with a laser fiber inserted into a 21 Ch panendoscope. Using a power varying from 40 to 50 watts/4 sec, the whole surface of the remaining prostatic capsule was irradiated. After the treatment an indwelling catheter was left in place for 2-3 days and then the patient discharged from the hospital. There were no side effects. Potency and continence were preserved. Now with an average follow-up of 24 months, all patients have negative biopsies and no tumor progression.

Transurethral resection of the prostate (TURP) has been combined with Nd:YAG application for the treatment of prostatic carcinoma for a decade. The inability to deliver the energy at right angles has made the procedure technically difficult, but results have been encouraging. A pilot study was begun in 1991 on ten patients who refused or were not candidates for radical prostatectomy. The protocol consisted of transrectal ultrasound imaging (TRUS) during extended TURP (EXTURP) followed immediately by Nd:YAG energy applied to the prostate bed and capsule. A second laser application under real time TRUS followed in eight weeks and a third (or fourth in one patient) was undertaken eight weeks later. Energy of 30,000- 85,000 Joules was applied during each procedure with the right angle urolase fiber (Bard) at 60 watts. Lesions were created for 30-60 seconds in each area of remaining tissue documented on TRUS. A thermocoupler was used to monitor rectal temperature. Complications include urinary retention, gross hematuria, bladder neck contracture, early incontinence, late incontinence, and probable permanent incontinence. Of the only four potent patients preoperatively, all (100%) are impotent now. TURLAP appears to be a safe and effective method of killing prostate malignant tissue and should be further studied perhaps in combination with interstitial laser irradiation to increase efficacy and lessen complications.

Laser photoirradiation has been delivered endoscopically for the treatment of both benign prostatic hyperplasia and early localized prostatic carcinoma. In treating carcinoma, aggressive transurethral resection of the prostate has been followed with laser irradiation to the remnants of malignant capsular disease. No attempt has been made heretofore to completely destroy the glandular prostate using laser irradiation alone. We performed a two-stage endoscopic laser prostatectomy in 6 adult mongrel dogs in an attempt to completely destroy the glandular prostate. Although no complications developed, histologic evaluation of the prostate revealed viable glandular elements in the midst of necrosis and atrophy. We conclude that in order to accomplish total ablation of the glandular prostate using laser photoirradiation, more precise thermal telemetry is needed.

Laser energy has been used by many for transurethral incision of small, obstructive prostates, vesical neck contractures, and urethral strictures. The customary techniques of moving the tip of the laser fiber through a cystoscope with a conventional laser guide, almost tangentially to the tissue to be incised, or drilling radially arranged holes in the scar, or both, have been cumbersome and imprecise. To provide exact control of the laser fiber and precise delivery of laser energy, a new guide was devised. It conducts the quartz fiber through the sheath and along the lens of an optical urethrotome. The tip of the quartz fiber contacts the tissue at an angle of 20 degree(s). KTP/532 laser energy is used to perform internal urethrotomy for urethral stricture, transurethral incision of postoperative contracture of the vesical neck, and transurethral incision of the small prostate under constant visual control. Recently, a straight version of this guide, called probe director, was devised to conduct the newly marketed lateral firing laser probes. This probe director allows precise control of such a probe within the prostatic urethral lumen and excellent maneuverability of the probe during transurethral laser prostatectomy.

Upper urinary malignancies are rare tumors whose diagnosis sometimes represents a difficult dilemma. In selected cases, it is possible to treat the tumor with laser irradiation. This approach is reserved to low-stage low-grade tumors, a tumor in a solitary kidney, bilateral syncroneous disease or patients with deterioration of renal function. Thirty one patients suspected to have malignancies, as they presented upper tract filling defects at IVP, underwent uretero-pyeloscopy to confirm the diagnosis. Twenty patients with upper urinary tract urothelial tumors were treated with Nd:YAG laser irradiation. Before the procedure, the ureter and the pelvis were accessed by 0.038 inch guide-wire or 4 French ureteral catheter. A power of 25 - 30 watts/3 seconds was carried out for the laser irradiation of the tumor and of the base. Sometime after the procedure a ureter single J catheter was left indwelling for 48 hours. In the follow-up the patients had endoscopic surveillance every three months. Actually 12 patients are tumor-free after 3 - 36 months. Eight patients had a recurrence after the first treatment and they underwent new laser irradiation. All the recurrences were in other sites of the upper urinary tract and seemed to be related to tumor grade. In conclusion, conservative endourological ureteropyeloscopy coupled with Nd:YAG laser irradiation should be considered a useful treatment in selected patients.

Analysis of possible ways for organic minerals destruction by laser-induced shockwave is presented. Physical mechanisms describing lithotripsy with microsecond laser pulses are discussed. Theoretical considerations show that the most probable fragmentation mechanisms are connected with the existence of absorptive inclusions in the stone volume. We have shown that surface plasma flash may be considered as attendant phenomenon which does not necessarily play an important fragmentation role under our conditions of observation.

In this paper we report the results on the destruction of several types of stones in aqueous media by radiation of Er:YSGG laser transported through fibers, i.e., under the conditions simulating those of the human body. The lasers operated in both Q-switched mode and in free lasing. For experiments, we used fluoride and quartz fibers with core diameters of 0.2 and 0.4 mm respectively. A fluoride fiber approximately as long as one meter transmits not less than 80% of the incident radiation and exhibits good strength (it survives bending with a curvature radius of about 2 cm). Quartz-quartz fiber with polymer cladding was made of dried quartz in the Institute of General Physics. Transmission of a 0.5-m piece was up to 50%. The laser used Cr:Er:YSGG rod (diameter 4 mm, length 75 mm), concentrations of Cr and Er ions were 2.10²⁰ and 4.7.10²¹ cm^-3 respectively. Both free lasing and Q- switched modes were tried, pulse durations being about 100 microsecond and 100 nanosecond respectively. Repetition rates were from 1 to 5 Hz. Radiation was put into fibers with the use of a fluoride lens with focal length 20 mm. The mass of material (Delta) m removed by ablation was determined from the volume of cavities produced by laser radiation and the stone's density, the volumes having been measured using a microscope.

We used the holmium:YAG (Ho:YAG) laser successfully to fragment human urinary calculi of various sizes and compositions. At an energy level of 0.5 J/pulse and a frequency of 5 Hz, lithotripsy resulted in minimal ureteral-wall injury that was limited to superficial coagulative necrosis of the submucosa. Increasing the amount of energy or the frequency level, however, often resulted in significant damage to deeper ureteral tissue. When performed at low power settings with care to avoid direct ureteral-wall contact, Ho:YAG laser lithotripsy is safe and effective.

Laser lithotripsy is now an accepted modality for the intracorporeal fragmentation of urinary tract and, to a lesser extent, biliary tract calculi. However, under conditions where constant direct vision is not possible or compromised, the risk of inadvertent laser damage to healthy soft tissue cannot be discounted. This is especially true at the higher laser pulse energies required to fragment the more recalcitrant stones. A series of in vitro and in vivo investigations are described which demonstrate a method and apparatus for the automatic feedback control of laser lithotriptors. In preliminary experiments, the control device, incorporated into a commercial flashlamp-pumped dye laser, is shown to significantly improve the margin of safety against laser tissue damage while still allowing effective stone fragmentation. The practical implications of our findings for the clinical possibility of `blind' laser lithotripsy are discussed.

Laser lithotripsy is based on laser induced plasma formation. Successful stone fragmenting is dependent on power density at the fiber tip in contact with the stone and on the absorption of laser radiation by the stone itself. The use of the laser has been ineffective in the treatment of hard stones and of stones that absorb only minimal amounts of laser radiation. In our experimental and clinical studies we used Rifamycin (Rifocin) as a photosensitizer for the pulsed Dye laser and Sterile Indocyanine Green (Cardio Green) for the pulsed Alexandrite laser. We found that the use of these substances significantly increased the effectiveness of the laser in the treatment of those stones.

Laser pulses from a flashlamp pumped, solid state Ti:sapphire laser (Vuman, free running untuned wavelength 792 nm, 2 microseconds pulse width and up to 240 mJ pulse energy) have been successfully and efficiently coupled into thin optical fibers. The coupling efficiency can be up to 67% for 300 micron and 43% for 200 micron core diameter optical fibers. With these two optical fibers in vitro laser lithotripsy has been performed successfully on various human calculi including gall bladder, kidney, ureter and salivary duct stones. The bright white flash of the induced plasma emission, strong shock waves, fiber recoil and stone propulsion and the splattering of the stone chips have been observed during the calculi fragmentation.

In the following study three different pulsed laser lithotripsy systems were compared for the fine fragmentation of identical sets of natural and synthetic gallstones `in vitro.' Using a pulsed coumarin dye laser (504 nm), a pulsed rhodamine 6G dye laser (595 nm), and a pulsed Alexandrite laser (755 nm) a total of 184 concrements of known chemical composition, size, and weight were disintegrated to a fragment size of <EQ 4 mm. To investigate the transferability of the results to stones of strongly varying sizes and weight, 64 concrements (7.2 - 20.1 mm/0.10 - 2.80 g) from three human `gall stone families,' were fragmented at constant laser parameters. All stones could be reliably disintegrated using the three laser systems at the different settings tested. Even though in our experimental set up the rhodamine 6G dye laser showed the best results, theses were not statistically significant to results obtained with the coumarin dye and the Alexandrite laser at high pulse energies. The mean fiber burn-off of the Alexandrite laser at 80 mJ (Do80:195 mm/cm³ stone vol.) was however 5 to 81 fold higher than with all other laser systems, a fact of clinical relevance as far as possible side effects of the quartz material in the bile duct are not yet known.

The aim of this study was to determine the optimal parameters for an Argon laser (spot diameter equals 200 micrometers ) to obtain and reproduce vessel anastomoses. It was performed in 2 groups of Wistar rats. In the first group (89 shots on 10 carotids), the fluence was continuously adjusted from 30 to 3,000 J/cm² in order to determine an optimal set of parameters (power from 90 to 200 mW, shot duration from 0.1 to 5 seconds, pulsed or continuous mode). In the second group, thirty end-to-end carotid anastomoses were evaluated by macroscopic, thermal and histological studies. The second group proved the efficiency of the selected parameters. Vessel welding was obtained with 100 mW, 3 seconds, continuous mode (fluence equals 950 J/cm², irradiance equals 320 W/cm²) for a mean temperature of 77 degree(s)C corresponding to collagen denaturation. In the second group the patency rate was 93% (28/30) with 3 pseudo-aneurisms and 2 thromboses. Histological studies noted slight modifications of the media.

An experimental work on diode laser assisted end-to-end microvascular anastomoses on femoral arteries and veins of rats is presented. Effective welding of vessel tissues was obtained at low laser power by enhancing laser absorption with Indocyanine green (Cardio-green) solution. Clinical and histological effects of this laser technique were examined and compared with those obtained from the conventional microvascular sutured anastomosis technique.

In this study, 101 consecutive laparoscopic transabdominal preperitoneal hernia repairs (LTPR) were performed in 62 patients by a single surgeon. The series was begun in April 1991, and involved repair of 49 direct, 41 indirect, 4 femoral, 3 umbilical, 3 sliding, and 1 incisional hernias. Twelve cases were bilateral, eleven hernias were incarcerated, and fifteen hernias were recurrent. There were no intraoperative complications, and none of the procedures required conversion to open surgery. Patients experienced the following postoperative complications: transient testicular pain (1), transient anterior thigh paresthesias (2), urinary retention requiring TURP (1), and hernia recurrences (2). Follow up has ranged from 4 - 15 months and initial results have been encouraging.

The unprecedented rapid and successful adoption of laparoscopic cholecystectomy has prompted the evaluation of converting other standard open surgical procedures to a laparoscopic technique. A wide variety of laparoscopic acid reduction procedures have been successfully accomplished by groups in this country and abroad. Our group reviewed the literature on the many types of open peptic ulcer operations, as well as the ones performed laparoscopically. We elected to perfect the technique of posterior truncal vagotomy and anterior seromyotomy (PTVAS). After extensive animal laboratory work, we performed PTVAS on four patients with documented recurrent peptic ulcer disease. We describe our technique as it evolved and in particular note the usefulness of endoscopic esophageal transillumination. In addition, we report our results and discuss their implications.

The concept of transmyocardial revascularization (TMR) providing blood flow to the left heart muscle based on the reptilian heart model has now been extended from an adjunctive procedure with coronary artery bypass to sole therapy. At Seton Hospital and Medical Center TMR is now being performed for the first time in clinical trials with patients who have no other mechanism of perfusion and a history of either failed PTCA or coronary artery bypass, with angina already under maximum medical therapy with a demonstrable ischemic muscle target. Longevity and reperfusion by tomographic thallium of these laser-drilled holes has been previously demonstrated but effectiveness of these channels for primary perfusion (sole therapy) apart from normal coronary bypass collateral supply is under investigation. Phase I of the FDA study has been completed with 15 cases and now Phase II includes three other beta test sites along with alternative therapy in marginal cases as the investigational format for the next 50 cases. More than 2 year followup in the first 15 cases is presented.

Cholecystostomy is frequently performed to obtain control of sepsis in high risk patients with acute cholecystitis. Retained stones in the gallbladder may cause future clinical problems. We present two patients with cholecystostomy tubes managed non-operatively. A review of other reported methods for stone extraction or destruction is also presented. Knowledge of safe and effective techniques for removal of these stones, using minimally invasive techniques is useful to the general surgeon.

The face of surgery is changing rapidly since the advent of the laparoscopic cholecystectomy and the heightened interest in minimally invasive surgery. There is little question that the expansion of minimally invasive techniques and technology are driven by patients and industry. These factors are counter to the mainstream of general surgeons who remain reluctant to accept change despite declining numbers of general surgeons, an increasing trend toward sub-specialization and shrinking spectrum of diseases being treated. The enthusiasm for laser applications in general surgery is declining despite an ever-increasing array of wavelengths, increasingly complex and expensive technology and the availability of multiple delivery devices. The future of surgery holds several opportunities for the refinement of laser and minimally invasive surgical technologies and their application to routine problems. However, the challenge for the future must remain a balance between the availability of technology and cost containment. This paper examines the challenges and future directions for lasers and minimally invasive techniques in general surgery.

There are many different possibilities for using lasers to treat an obstructing prostate gland. The laser may be used in a continuous wave or pulsed mode. The wavelength may be well absorbed by the prostatic tissue (such as with KTP or holmium lasers) thereby improving the cutting action; alternatively the wavelength may be poorly absorbed by the prostate (such as with gallium arsenide or neodymium YAG lasers) thereby promoting coagulation. The delivery device may be a simple bare laser fiber used free beam or contact; it may be delivered via a contact tip or diffuser probe; alternatively the laser may be deflected through a right angle via for example a gold-coated fiber. Finally the laser may be delivered via a balloon which is inflated within the prostate. Over 100 patients have been treated. Flow rates and post-micturition residual on ultrasound, PSA, transrectal ultrasound (TRUS) volume were recorded preoperatively on all patients unless in acute retention in which case only the PSA and TRUS volume were performed. Postoperatively these measures were all repeated at 3 and 6 months.

The gallium arsenide semiconductor laser at 805 nm has been used with a variety of delivery fibers to produce actions varying from incision to interstitial coagulation. Clinical experience at this early stage suggests that the laser can be used to cut skin and connective tissue efficiently in air. It may prove at least as effective as the neodymium YAG laser for interstitial coagulation of tumors or prostate. Further efforts are required to promote its action cutting underwater and as a coagulator both in air and water.

The pulsed dye laser used with a 1 microsecond pulse duration at 504 nm delivered via a 320 micron core fiber is designed specifically for ureteric calculi. The threshold for stone fragmentation is in the region of 40 to 50 mJ for the majority of stones. Fragmentation is efficient in the 60 to 70 mJ range but for some stones 100 mJ is required. The Candela MDL 2000 (Candela Corporation) is capable of delivering 140 mJ. This laser has minimal effect on tissue. The holmium laser delivers 300 microsecond pulses of 2.1 microns wavelength (Sunrise Technologies and Coherent Ltd). A maximum of 1 J per pulse at 5 Hz is usually recommended because of the significant action on tissue. Even using this regimen significant damage can be inflicted on the ureter. In this paper the action of these two laser regimens on stones is contrasted.

The overall development of laser use in urology is recessing. The reasons are the refinement of methods of radical surgery and the continuing development of alternative technologies involving electric current. Taking the cost factor into account, are lasers still opportune in medicine? The answer is definitely yes. Cost reduction in medical practice without quality loss is only possible with effective methods of minimally invasive surgery. Continuing investigation of cutting, welding, coagulating and ablating instruments is justified. Competition of lasers to other technologies can only be beneficial to the cause. But where are the highlights of laser applications? The unsurpassed utilization of optical properties of lasers lie in the concept of photodynamic therapies and in optical feedback mechanisms for laser applications. The combination of lasers with three dimensional visualization of the treatment area by ultrasound (TULIP-procedure for benign prostatic hyperplasia) is a novel approach in laser application. The further development of these treatment modalities will reveal the true benefit of laser technology in urological applications.