The role of lasers in infertility surgery

Transcription

1 FERTILITY AND STERILITY Copyright 1984 The American Fertility Society Printed in U.8A. The role of lasers in infertility surgery James F. Daniell, M.D. The Women's Health Group, Nashville, Tennessee Since the first reported use of the CO 2 laser intraabdominally for female reconstructive pelvic surgery in 1974, 1 much has been written about the use of lasers for infertility surgery both in medical journals and in lay publications. The media publicity given to the visually impressive moving beam of a CO 2 laser bloodlessly vaporizing human tissues is to be expected, considering the high interest in technology by today'sjournalists. Unfortunately, many patients have too easily accepted some of the glowing claims made for infertility surgery performed with lasers, while too many surgeons not personally familiar with surgical lasers have been quick to make negative statements concerning lasers. It is normal for skepticism to exist in the minds of many infertility surgeons concerning the real benefits of laser surgery, considering the expense of the hardware, the lack of available data, and the small numbers of surgeons that have as yet had an opportunity to gain hands-on experience in either laboratory animals or clinically with lasers. As more longterm follow-up becomes available and respected researchers begin to critically and unemotionally investigate the various surgical lasers that are available today, meaningful data will be forthcoming from both animal and clinical studies. Thus, the real role of lasers in infertility surgery is not yet determined and must await the results of future and ongoing investigations. The goal of this article is to review the various surgical lasers that have been used in infertility surgery and report briefly the methods of use and results reported from both research and clinical investigations. TYPES OF LASERS IN INFERTILITY SURGERY Of the many lasers that have been used in various surgical fields, three have been used in gynecology-the CO2, the argon, and the neodymium:yttrium-aluminum-garnet (Nd:YAG). Each of these lasers has a specific wave length and, thus, different characteristics and tissue effects. These properties are listed in Table 1. As can be seen, both the Nd:YAG laser and the argon laser can be delivered via flexible fibers and passed through fluids, which are advantages over the CO 2 laser with regard to the ease of delivery. The amount of scattering of the beam and the depth of penetration also vary for these lasers. Only the CO 2 laser can allow vaporization and precise incision of tissue with any degree of effectiveness. Thus, the CO 2 laser has been, and will continue to be, the primary laser used for female infertility surgery. BIOPHYSICS OF THE CO 2 LASER Radiation from the CO2 laser has three special qualities: it is coherent, collimated, and monochromatic. Coherent radiation is when the waves are exactly in step (phase) with each other in both time and space. Monochromatic waves have exactly the same wavelength (or color if they are visible). Collimated rays are parallel to each other. The radiation of the CO 2 laser occurs at a wavelength of 10.6 f.lm in the infrared portion of the spectrum, which is invisible to the human eye. Carefully placed mirrors, one at each end of the laser resonator chamber, allow the 10.6-f.Lm co- Daniell Lasers in infertility surgery 815

2 Table 1. Different Properties of Surgical Lasers Nd:YAG Argon Wave length of 10.6 fj.m 1.06 fj.m 0.5 fj.m laser Primary tissue Vaporization Coagulation Coagulation effect Color-dependent No Yes Yes Scattering of None Moderate Slight beam Effect on water Beam strong- Beam slight- Beam not ably absorbed ly absorbed sorbed Passed through No Yes Yes fibers Depth of tissue 0.1 mm 4 mm 0.5 mm effecta aln comparison studies in rat and rabbit bladders. herent waves to reflect back and forth many times along, the axis of the tube, thus amplifying the radiant energy emitted. The power of an unfocused CO 2 laser beam is relatively low when compared with the beam surface area. By a system of optics, using special focusing lenses, the emitted column of laser energy must first be focused further so that it can be applied for use surgically. The selection of a lens for a specific application is a function of minimum spot size and depth of focus. Due to their high degree of coherence, laser beams can be focused to a very small spot, with an energy power density considerably higher than in the parallel beam. The importance of coherence and collimation can be illustrated by comparing a 60-watt electric bulb with a CO 2 laser producing 60 watts. Trying to focus the white light from a bulb with lenses will yield only a fraction of the emitted light energy at the focus because the bulb is emitting light in all directions. But the coherent beam from the CO2 laser can be focused onto a tiny spot and generate enough energy to easily burn a hole in a block of wood. There are certain properties of the CO 2 laser that make it advantageous for surgical procedures: (1) The energy is highly absorbed by nonreflective solids and liquids, notably water (the major constituent of most cells). In water this radiant energy is absorbed almost completely at a depth of 100 f.lm from the surface. (2) The absorption ofthe beam is similar on tissues of any color. (3) The energy does not cause genetic mutation of the cells. The effect of the waves from the CO 2 laser in any absorbing material is by conversion of radiant energy to heat. (4) There is minimal scattering from the point of impact. (5) The energy destroys tissue (including bacteria) by in- 816 Daniell Lasers in infertility surgery stantaneous boiling of the cellular water at 100 C. (6) The e.nergy of the laser can be efficiently reflected by the user with mirrors of highly polished metals. (7) The energy of the CO 2 laser may be focused to a spot diameter < 1 mm with minimal energy loss by using special lenses. (8) CO2 laser systems delivering enough power for intraabdominal surgery are compact and will operate from an ordinary electrical outlet. ACTION ON TISSUES BY THE CO 2 LASER The laser destruction of tissue is by vaporization of cellular elements. The tissue is incised by the boiling of intracellular and extracellular water to form steam, which expands explosively and disrupts tissue (carrying cellular debris out of the wound). Some ofthe debris is charred as it passes through' the beam, and some ignites and burns. The actual area of laser impact does not show any' sign of tissue combustion; the laser appears to destroy by vaporization of cellular water at a temperature of only 100 C at the impact point. Measurements of the velocity at which steam expands from the pointoflaser impact reveal that the pressure exerted on adjacent tissue by cell disruption is small and unlikely to cause damage by shock waves or scatter of materials to adjacent sites. Histologic examination of sections from laser wounds on various organs has shown that some cellular damage occurs up to 500 f.lm from the laser impact but that the depth of thermal necrosis is usually < 100 f.lm. With normal blood flow in vessels, veins and arteries up to 0.5 mm in diameter can be sealed by the laser. If the flow is first stopped, vessels up to 2.0 mm can be sealed, as compared with vessels 0.5 to 1.0 mm in the case of cutting-diathermy. METHODS OF DELIVERING THE CO 2 LASER TO THE TISSUE Acquiring confidence and skill in the use of the CO 2 laser for infertility surgery requires adaptation to a whole new "no-touch" form of operating. The tissue effect ofthe laser for incising, vaporizing, and coagulating tissue is a hands-off technique with the operator merely directing the beam and controlling the time and power density of the impact of the laser on the tissue. The beam can be delivered either at open surgery or under laparoscopic control for clinical use in female infertility operative procedures. At laparotomy, the Fertility and Sterility

3 Table 2. Comparison of Methods of Use for Infertility Surgery Lapa Micro Hand-held roscopy scope scalpel Avoid major Yes No No surgery Requires extra Yes Yes No hardware Easy to use Yes Yes No deep in pelvis Mirror use No Yes Yes possible Easy to vary No No Yes spot size Magnified tis Yes Yes Yes, with loupes sue view is possible Good light Yes Yes Yes, with fiberop visibility tic headlight Fine control of Yes Yes No beam with micromanipulator Simple assembly No No Yes CO 2 laser can either be used with a simple handheld probe attached to an articulated arm or via an operating microscope with a laser micromanipulator attached. There are obvious advantages, disadvantages, and differences in each method oflaser beam delivery. These are outlined in Table 2. The overall goals of the surgeon and patient, the amount and type of disease present, the availability of delivery systems, and the level of experience and training of the operator will all influence the specific method of use of the CO 2 laser for an individual case. The hardware for delivery of the CO 2 laser beam for surgical uses is constantly being improved. At this writing this hardware includes easily usable, sterilizable hand pieces with focal lengths from 125 to 50 mm, variable spot size lenses for microsurgery (with excellent focusing and fine control of the beam by micromanipulators), and both second puncture and operative channellaparoscopic delivery systems. LABORATORY EVALUATION OF THE CO 2 LASER As with any emerging technology, the CO2 laser has been the subject of many studies investigating the tissue effects of the beam and the results of various animal experiments. The question of carcinogenic risks of the CO2 laser beam was the subject of a study by Apfelberg et al. 2 in which mouse fibroblasts in tissue culture were exposed to the CO2 laser. These cells were grown for nine generations and studied for their malignant transformation potential. This study did not show any increased incidence of malignant transformation of the cells when compared with normal, nontreated control mice. Early animal studies of surgical intraabdominal CO2 laser procedures included those of Klink et al.,3 who in 1978 reported a technique of laser welding of the uterine cornua of 40 rabbits and in an unspecified number of surgically removed human fallopian tubes. They suggested that CO 2 laser welding might be a quick and effective technique for tubal anastomosis in humans. Baggish and Chong,4 however, looked more closely at this suggested welding technique both in seven rabbits and in four patients with obstructed tubal segments. They found that laser welding did nothing to hold the anastomosis together structurally and concluded that the technique had little value for human tubal surgery. They did, however, comment favorably on the hemostatic properties of using the CO2 laser as a cutting tool during pelvic reconstructive surgery. Fayez et al.5 reported, in rabbits, that they were unimpressed with laser welding of the tube. In addition, they compared needle cautery of the tube versus laser transection prior to anastomosis with 8-0 nonreactive sutures. They found the laser transection group of rabbits to be less fertile. They concluded that the CO2 laser in the TMoo mode with a 1.8 mm spot size had no place in tubal reanastomosis. However, Baggish,6 in the "Editor's Corner" of the same journal, noted that this study was done with an older laser with lower power densities and thus probable greater thermal damage potential. Choe et al.,7 in a more recent study, compared conventional microsurgical reanastomosis with laser microsurgical techniques of ligated uterine rabbit horns. Using the same CO 2 laser and techniques similar to those of Fayez et al.,5 they concluded that laser microsurgery produced significantly less adhesion formation and comparative patency rates in rabbits. Other studies designed to evaluate postoperative intraperitoneal adhesion formation following CO 2 laser surgery included those of Pittaway et al. B and Bellina et al. 9 In the first study,b 31 rabbits received standard injury to the uterine horns and ovaries; then hemostasis was obtained either with the CO2 laser or with bipolar cautery. The animals were sacrificed 5 weeks later, and the adhesions were graded in a blinded fashion. The results indicated no difference in the number of Daniell Lasers in infertility surgery 817

4 Table 3. Reported Clinical Results of Infertility Surgery with CO 2 Laser (Laparotomy) Author Type of surgery Length of follow-up Results No. of patients Term pregnancy Abortion Ectopic Bellina13 All types of micro- 24 surgery: Initial procedure 24 Repeat procedure 24 Reversal of steril- 24 ization Mage and Bruhat14 Salpingostomy 21 Tulandi15 Salpingostomy 10 Kelly and Roberts16 Salpingostomy 12 Adhesion vaporization 12 Reversal of steril- 12 ization Anastomosis of patho- 12 logic tubal blockage Chong and Baggish17 Conservative endome- 6 triosis surgery (AFS stages: II to IV) Diamond et aub Salpingostomy, adhe- 12 sion vaporization, and surgery McLaughlin19 Myomectomy 12 ans, not stated. mo (36%) Nsa 4 (4%) (43%) NS NS (32%) NS NS (71%) NS NS 38 9 (24%) 4 (10%) 3 (8%) 11 3 (27%) (7%) 0 1 (5%) 21 4 (19%) 1 (5%) (67%) (25%) 1 (13%) (61%) NS NS 13 (stage II) 11 (85%) 8 (stage III) 3 (38%) (36%) 2 (2%) 2 (20%) 5 2 (40%) 0 1 (20%) adhesions formed and the investigators suggested that the ovaries were more prone to develop postoperative adhesions than the uterine horns. In the second report,9 comparative incisions on six rabbit peritoneums were made with the CO 2 laser and electrosurgical microneedles. The animals were sacrificed on days 5, 10, 15,20, and 25; and the incisions were studied grossly and histologically. The investigators found adhesions to be absent in all the laser incisions but present in all the electrocautery sites. They concluded that the CO 2 laser caused less tissue injury both immediately and throughout the healing phase. There have been fewer reports investigating use of the CO2 laser under laparoscopic control in animal models. Daniell and Brown 10 tested a prototype system for aiming and firing a CO 2 laser beam down the operative channel of a modified laparoscope in four rabbits. They reported success in vaporizing target areas on the peritoneal sidewalls without complications but had problems with visibility of the orange helium neon target laser due to intraperitoneal smoke accumulation. Maintaining an adequate pneumoperitoneum and lens fogging was also an initial problem, but this was eventually solved by developing a special lens coupler and by using a regular laparoscope and a special second puncture probe to introduce 818 Daniell Lasers in infertility surgery the laser beam. ll Tadir et al. 12 also recently reported their animal studies in Israel with both operative channel and separate puncture delivery of the CO 2 laser beam intraperitoneally under laparoscopic control. From their pioneering work evolved a system of equipment that is now clinically very effective. CLINICAL EXPERIENCE WITH CO 2 LASERS IN INFERTILITY SURGERY The CO 2 laser has been used for procedures encompassing almost the entire field of female reproductive surgery. The list includes cornual reimplantation, tubal transection for anastomosis, adhesiolysis, fimbrioplasty, neosalpingostomy, metroplasty, myomectomy, vaporization of ectopic gestation, conservative surgery for, ovarian wedge resection, and uterosacral ligament vaporization. Unfortunately, most reports have been anecdotal and uncontrolled, and the number of subjects has been small. Thus, the basic question of true efficacy remains unanswered. The reported clinical results presently available for review are listed in Table 3 for open infertility surgery and in Table 4 for laparoscopic CO 2 laser surgery. Fertility and Sterility

5 Table 4. Reported Results of Laparoscopic Use of the CO 2 Laser Author Type of Length of surgery follow up Daniell and Brown 1O Vaporization of 5 Tadir et a!. 12 Sterilization 24 Vaporization of Adhesiolysis Kelly and Roberts 21 Vaporization of 6 Martin 22 Vaporization of 12 (AFS scores 1-20) Feste 23 Vaporization of 24 Daniell and Herbert 24 Terminal salpin- 9 gostomy Nezhat 20 Terminal salpin gostomy Vaporization of 6 ans, not stated. 17W Results No. of patients Term pregnancy Abortion Ectopic 10 3 (30%) 0 o 12 1 pregnancy (8% failure rate) 7 Nsa NS 3 (30%) 17 (33%) 16.(76%) 3 (14%) 4 (16%) 12 (56%) 3 (30%) 0 NS 0 5 (24%) 0 1 (5%) 1 (5%) 1 (4%) 1 (4%) 3 (13%) 0 RESULTS OF OPEN INFERTILITY SURGERY Bellina 13 reported 230 cases of tubal reconstructive surgery with 2 years' follow-up. Unfortunately, he did not report his data in such a way that specific procedures could be accurately analyzed. He did, however, report a 37% conception rate for correction of bipolar tubal disease and a 32% pregnancy rate for repeat procedures, which are extremely impressive. Mage and Bruhat14 reported a comparative series in which terminal salpingostomy using microsurgical techniques was performed in 30 cases with electrosurgery and then, following that series, in 38 cases with the CO 2 laser. They noted a 24% term pregnancy rate with less follow-up time in the laser group, compared with 17% in the electromicrosurgery series. They stated that use of a short focal length hand piece was superior to a micromanipulator laser beam delivery system, and suggested that the laser might be a safe and effective alternative to electrosurgery in tubal surgery for correction of distal disease. Tulandi,15 in a prospective randomized study, compared the CO 2 laser with microdiathermy needle salpingostomy. The pregnancy rates at 10 months were similar (27% to 25%), but the surgery-to-conception time was less in the laser group. He felt this might reflect more rapid healing of the tube after laser surgery. In yet another study, Kelly and Roberts,16 with I-year follow-up, reported only a 7% pregnancy rate for CO2 laser terminal salpingostomy. However, with a second year of follow-up, this group of patients achieved a 30% pregnancy rate; This underscores the need for longer follow-up before conclusions can be drawn regarding the efficacy of CO2 laser surgery for salpingostomy or other tubal reconstructive surgery. Although many surgeons are now using the CO2 laser intra abdominally for vaporization, there have been few clinical reports to date. Chong and Baggish17 reported the cases of 23 patients with stage II to stage IV disease (according to The American Fertility Society classification) who underwent conservative surgery for with the use of the CO 2 laser both via the micromanipulator and the freehand piece of the laser's articulated arm. They described techniques for vaporization of implants, lysis of adhesions, and ovarian excision procedures. Their 6-month pregnancy rate of 61% included 85% for stage II and 38% for stage III, but no pregnancies in two cases of stage IV disease. In addition, 78% of these patients received danazol postoperatively in an unrandomized fashion. They concluded that the CO 2 laser offered the technical advantages of a bloodless field, precision destruction by vaporization, and the ability to treat poorly accessible areas. They recommended that further evaluation of the CO 2 laser in a randomized, collaborative, prospective study was needed before any conclusions concerning ef- Daniell Lasers in infertility surgery 819

6 ficacy for major surgery could be drawn. A prospective multicenter study that involved use of early second-look laparoscopy to evaluate postoperative adhesion formation after CO2 laser infertility surgery has recently been published.1s This study was not randomized and had no control subjects. In spite of those deficiencies, the report was the first to accurately assess the occurrence of postoperative adhesions following intraabdominal female infertility surgery using the CO2 laser. These investigators found postoperative adhesion formation to be significant (91 of 106 patients) and concluded that the CO2 laser was not a panacea for the treatment oftuboperitoneal causes of infertility. The CO2 laser has also been used for performing abdominal myomectomies. McLaughlin19 reported his technique and results in eight patients, with a 40% term pregnancy rate in the five patients attempting conception. He believed that his laser technique was superior for performing myomectomies by providing improved hemostasis, better precision for removing the myomata while preserving normal uterine tissue, and by the ability to reach previously inaccessible areas. He believed that due to improved wound healing, postoperative adhesions appeared to be reduced. Unfortunately, he had no control subjects, small numbers, and only 8 months' follow-up. CLINICAL RESULTS OF CO 2 LASER LAPAROSCOPY The use of the CO2 laser through a laparoscope was first reported by Bruhat et al.25 for operative channel techniques and by Tadir et al. 26 for second puncture use with a diagnostic laparoscope. These authors initially investigated use of the CO2 laser to perform tubal sterilization procedures. However, Tadir and associates12 now state that "This procedure cannot be recommended for sterilization" because of tubal recanalization. Numerous laparoscopic operative procedures have now been reported to have been performed with the CO2 laser. Some of these are listed in Table 5. Several authors10-12, have now reported successful use of the CO2 laser to vaporize endometrial implants under laparoscopic control with safety and efficiency. All these investigators indicate satisfaction with this new innovative method of selectively destroying visible areas of 820 Daniell Lasers in infertility surgery Table 5. Operations That Have Been Performed with the CO 2 Laser Laparoscope 1. Vaporization of 2. Terminal neosalpingostomy 3. Uterosacral ligament ablation 4. Pelvic adhesiolysis 5. Vaporization of small uterine fibroids 6. Ovarian cystotomy 7. Ablation of hydatid cysts 8. Vaporization of ovarian fibromas without damaging adjacent tissues. Laparoscopic salpingostomy, which has been performed with classic operative laparoscopic techniques, has certain risks, especially if cautery is used Daniell and Herbert24 have recently reported a series of22 patients with I-year followup who underwent CO2 laser terminal salpingostomy with the CO2 laser laparoscope. The postoperative patency rate was 75% at follow-up hysterogram, and the term pregnancy rate was 14% in this series, made up of patients who had already undergone at least one previous tuboplasty. The authors believed the technique warranted further investigation with longer follow-up in a larger group of patients before any conclusions could be drawn. INVESTIGATIONS OF THE OTHER SURGICAl:. LASERS FOR INFERTILITY SURGERY Both the argon laser and the Nd:YAG laser have now been used investigationally for treatment of pelvic. Keye and associates reported laparoscopic use of the argon laser both in rabbits30 and in a small group of patients with.31 Their technique involves passing a 0.6-mm flexible quartz fiber through a second-puncture laparoscopic instrument with a steerable tip and firing the beam at endometrial implants. The argon laser, which is selectively absorbed by the hemoglobin of implants, is much easier to deliver to the planned impact site under laparoscopic control than is the CO2 laser. This new form of therapy for seems very promising and is being investigated further. Preliminary results suggest that the argon laser can be safe, effective, and easy to use laparoscopically. Unfortunately, the argon laser cannot be used for vaporizing or incising tissues; so its use seems limited to photocoagulation of pigmented lesions such as, either laparoscopically or at open surgery. Fertility and Sterility

7 The Nd:YAG laser, which has a delivery system similar to that of the argon laser, but a greater depth of penetration of tissue, has also recently been investigated by Lamano 32 for use laparoscopically to photocoagulate. This work, although preliminary, indicates that visible implants of can be coagulated without complications using the powerful Nd:YAG beam. The depth of tissue destruction that occurs (3 to 4 mm beneath the surface) and the lateral beam-scattering theoretically makes this laser more dangerous, especially when used near vital structures. A particular danger also exists for the surgeon, who must use special protective lenses to guard against retinal damage from the penetrating beam's backscatter. SAFETY OF LASERS CO 2 lasers have been used intraabdominally for over a decade on thousands of patients. There has been a very respectable safety record, the number of reported documented injuries being < 0.5%. Since CO2 lasers concentrate such a large amount of energy into a very small, collimated beam, they are definitely capable of doing significant damage if aimed and fired inappropriately. The types of immediate accidents that can occur include direct and indirect (e.g., a reflected beam) damage to tissues not planned to be the target of the beam, fires from ignition of flammable drapes or sponges, and anesthetic gas explosions. In addition, there is the problem of irritation to the surgeon's lungs from the vapor plume itself or vaporization of some chemical that may have been used in the operative field. These accidents can be avoided by use of protective glasses, nonreflective instruments, moist drapes and sponges, and proper venting systems. The Nd:YAG and argon lasers present more serious safety hazards because of the properties of backscatter of the beam (reflection back toward the operator from the impact site) and the ability of these lasers to pass through clear fluids (e.g., the vitreous). Thus, very high standards of safety and special lenses must be used with these specific lasers. Unfortunately, as more and more surgeons begin to use these various lasers, the number of accidents is sure to increase even if the rate remains the same. Therefore, all present and future users of surgical lasers must follow meticulous standards to ensure the highest level of safety for patients, physicians, and other medical personnel. Instrument manufacturers must also accept their share of responsibility for promoting safe use of medical lasers. Increasingly sophisticated lasers are becoming available, and thus manufacturers must constantly educate the medical community about the safe operation of their products. Failure to maintain adequate standards for the safe application of surgical lasers will result in increased governmental and institutional intervention and restrictions on both the development and the use of lasers for surgery. ACQUIRING TRAINING IN LASER SURGICAL TECHNIQUES One unique feature of undertaking to learn laser surgery for infertility problems is the difficulty in obtaining adequate hands-on clinical experience. Most residency programs do not yet offer intraabdominallaser surgery training. Thus, the interested gynecologist who desires to learn the special techniques unique to laser surgery must either attend organized courses or workshops or make arrangements to observe surgeons already active in the field. In addition, hospital committees are now setting strict credentialling guidelines that must be met by potential users of the surgical laser. This seems very appropriate, because the techniques used for CO 2 laser surgery intraabdominally require the understanding and application of a whole new technology-focused laser light. The minimal requirements should include exposure to didactic lectures on basics, safety, tissue effects, and delivery systems. In addition, "hands-on" activities that allow observation of tissue effects on laboratory animals are invaluable for learning the effects of the laser beam when used for coagulating, vaporizing, or incising tissues. A final requirement should be some sort of preceptorship arrangement where the interested gynecologist can observe actual surgical procedures similar to those he plans to undertake. These phases of learning in various combinations should provide the neophyte ample opportunity to acquire the knowledge and technical skills needed to perform safe intraabdominal laser surgery with open surgery or via laparoscopy. For the infertility surgeon already skilled in operative laparoscopic and microsurgical techniques, it should not be difficult to become an "expert" laser Daniell Lasers in infertility surgery 821

8 surgeon in a very short period of time once the hardware is available. FUTURE OF LASERS IN INFERTILITY SURGERY Just as the true, present role of surgical lasers is undefined,33 their future status for infertility surgical procedures remains unclear. Some things are certain. More technically advanced lasers will soon be available in more operating rooms. These will include small portable CO2 lasers with smaller spot sizes and more easily used delivery systems. Flexible fibers that can safely and efficiently allow passage of the CO2 laser may become a reality. Other, as yet undetermined, sources oflaser energy may become available and replace today's CO 2 lasers. For those involved in research and development of surgical lasers, there has been an increase in funding and a resurgence in investigation that may lead to exciting new lasers for clinical use in the future. In the final analysis, skilled surgeons knowledgeable in techniques of laser surgery and the combination of advanced laser technology may produce very favorable operative results. WHAT IS THE PRESENT ROLE OF SURGICAL LASERS IN RECONSTRUCTIVE PELVIC SURGERY? The intraperitoneal use of lasers in gynecology must, when considering the present available knowledge, be considered still to be in the developmental stage, because the present numbers of valid investigative studies are limited. Certainly, the precision of tissue destruction that is obtainable exceeds that possible by other surgical modalities when the present state-of-the~art laser delivery systems are properly applied. Thus, in spite of claimed improvements in surgical results with the use of the CO2 laser for difficult reconstructive pelvic procedures, the true benefits of the laser are still unproven in infertility surgery. There are certain advantages, but also disadvantages, that may result from undertaking a laser surgery program. The advantages, suggested by laser surgery investigators, include shorter operating time, less intraperitoneal bleeding, less touching of tissue, and less tissue injury. The probable, but as yet unproven, advantages are. reduced postoperative adhesion formation and improved chances of pregnancy. 822 Daniell Lasers in infertility surgery Finally, it is certainly fair to say that the CO 2 laser is not a panacea for the prevention of postoperative adhesions or an automatic guarantee of high pregnancy rates. The laser is just another surgical tool whose true use needs to be further defined and applied by skilled, thoughtful surgeons. It probably already has appropriate usefulness for specific procedures such as neosalpingostomy and will, with future technological developments, be used increasingly by trained surgeons for intraabdominal operations. It is a complicated apparatus with precise functions that requires reasonable skill and definite training time to acquire the ability for effective clinical use. Failure to accurately and adequately explore the uses of lasers in infertility surgery would be unscientific and counterproductive to true progress in our field. REFERENCES 1. Bellina JH: Gynecology and the laser. Contemp Obstet Gynecol 4:24, Apfelberg DB, Mittelman H, Chadi B: Carcinogenic po tential of in vitro carbon dioxide laser exposure of fibroblast. Obstet Gynecol 61:493, Klink F, Grosspietzsch R, von Klitzing L, Endell W, Husstedt W, Oberheuser F: Animal in vivo studies and in vitro experiments with human tubes for end-to-end anastomotic operation by a CO 2 laser technique. Fertil Steril30:100, Baggish MS, Chong AP: Carbon dioxide laser microsurgery of the uterine tube. Obstet Gynecol 58:111, Fayez JA, McComb JS, Harper MA: Comparison of tubal surgery with the CO 2 laser and the unipolar microelectrode. Fertil Steril 40:476, Baggish MS: Status of the carbon dioxide laser for infertility surgery. Fertil Steril 40:442, Choe JK, Dawood MY, Andrews AH: Conventional versus laser reanastomosis of rabbit ligated uterine horns. Obstet Gynecol 61:689, Pittaway DE, Maxson WS, Daniell JF: A comparison of the CO 2 laser and electrocautery on postoperative intraperitoneal adhesion formation in rabbits. Fertil Steril 40:366, Bellina JH, Hemmings R, Voros JI, Ross LF: Carbon dioxide laser and electrosurgical wound study with an animal model: a comparison of tissue damage and healing patterns in peritoneal tissue. Am J Obstet Gynecol 148:327, Daniell JF, Brown DH: Carbon dioxide laser laparoscopy: initial experience in experimental animals and humans. Obstet Gynecol 59:761, Daniell JF,.Pittaway DE: Use of the CO 2 laser in laparoscopic surgery: initial experience with the second puncture technique. Infertility 5:15, Tadir Y, Kaplan I, Zuckerman Z, Edelstein T, Ovadia J: New instrumentation and technique for laparoscopic carbon dioxide laser operations: a preliminary report. Obstet Gynecol 63:582, 1984 Fertility and Sterility

9 13. Bellina JH: Microsurgery of the fallopian tube with the carbon dioxide laser: analysis of230 cases with a two-year follow-up. Lasers Surg Med 3:255, Mage G, Bruhat M-A: Pregnancy following salpingostomy: comparison between CO 2 laser and electrosurgery procedures. Fertil Steril 40:472, Tulandi T: Hydrosalpinx: comparison of electrosurgery and laser surgery. Fertil Steril 41:73S, Kelly RW, Roberts DK: Experience with the carbon dioxide laser in gynecologic microsurgery. Am J Obstet Gynecol 146:585, Chong AP, Baggish MS: Management of pelvic by means of intraabdominal carbon dioxide laser. Fertil Steril 41:14, Diamond MP, Daniell JF, Martin DC, Feste J, Vaughn WK, McLaughlin DS: Tubal patency and pelvic adhesions at early second-look laparoscopy following intraabdominal use of the carbon dioxide laser: initial report of the intraabdominal laser study group. Fertil Steril 42:717, McLaughlin DS: Micro-laser myomectomy technique to enhance reproductive potential: a preliminary report. Lasers Surg Med 2:107, Nezhat C: Unpublished data 21. Kelly RW, Roberts DK: CO 2 laser laparoscopy: a potential alternative to danazol in the treatment of stage I and II. J Reprod Med 28:638, Martin DC: Interval use of the laser laparoscope for following danazol therapy. Fertil Steril 41:74S, Feste JR: Laser laparoscopy: a new modality. Fertil Steril 41:74S, DaniellJF, Herbert CM: Laparoscopic salpingostomy utilizing the CO2 laser. Fertil Steril 41:558, Bruhat M, Mage C, Manhes M: Use of the CO 2 laser via laparoscopy. In Laser Surgery III, Proceedings of the Third International Society for Laser Surgery, Edited by I Kaplan. Tel Aviv, International Society for Laser Surgery, 1979, p Tadir Y, Kaplan I, Zuckerman Z, Ovadia J: Laparoscopic CO2 laser sterilization. In Human Reproduction, Edited by K Semm, L Mettler. Amsterdam, Excerpta Medica, 1981, p Gomel V: Salpingostomy by microsurgery. Fertil Steril 29:380, Fayez J A: An assessment of the role of operative laparoscopy in tuboplasty. Fertil Steril 39:476, Mettler L, Giesel H, Semm K: Treatment of female infertility due to tubal obstruction by operative laparoscopy. Fertil Steril 32:384, Keye WR Jr, Matson.GA, DixonJ: The use of the argon laser in the treatment of experimental. Fertil Steril 39:26, Keye WR Jr, Dixon J: Photocoagulation of by the argon laser through the laparoscope. Obstet Gynecol 62:383, Lamano JM: Photocoagulation of early pelvic by the Nd:YAG laser through the laparoscope. J Reprod Med. In press 33. Daniell JF: The CO 2 laser in infertility surgery. J Reprod Med 28:265, 1983 Received June 4, Reprint requests: James F. Daniell, M.D., The Women's Health Group, 2222 State Street, Nashville, Tennessee Daniell Lasers in infertility surgery 823