国际微创妇科学会议热点
Highlights of the Global Congress of Minimally Invasive Gynecology， 34th Annual Meeting of the AAGL
2005年11月9－12日
美国伊利诺斯州芝加哥
November 9-12， 2005； Chicago， Illinois
Mark D. Levie， MD
At this years meeting， a number of presentations focused on global endometrial ablation techniques， and discussions ranged from the success of these techniques to their safety and to the kind of settings most appropriate for them to be performed in. Issues related to the concomitant performance of sterilization with global endometrial ablation devices were also discussed. Reviews of these presentations are the focus of this report.
Safety of Global Endometrial Ablation Techniques
Endometrial ablation is one of the newer technologic advancements available to Ob/Gyns to aid them in treating women with abnormal uterine bleeding. In the past， endometrial ablation required operative hysteroscopy with either resection or vaporization of the endometrial lining. These so-called first-generation techniques required some advanced hysteroscopic skills and were time-consuming. The newer second-generation techniques have attempted to overcome many of the drawbacks associated with the earlier techniques. These second-generation， or global， endometrial ablation techniques do not require operative hysteroscopic skills， and for the most part are performed without actual visualization. （The hydrothermal ablation technique is the exception.） They are easier to perform than first-generation techniques， save operative time， and avoid the risk of fluid overload.
One of the major issues associated with these techniques is the safety profile. Although there are limited reports in the medical literature regarding major complications， they are always a concern. Individual adverse events may never get reported in the literature； and even if a case does get published， there is often a lag from actual occurrence to publication. In their review of complications associated with global endometrial ablation techniques， Gurtcheff and colleagues[1] noted that a Medline search of complications yielded no reports that mentioned a bowel burn or a uterine perforation. Moreover， only 9 studies as of 2003 had reported on complications of these techniques in the literature.[1] There were 2 cases of hemorrhage， 1 case of pelvic inflammatory disease， 20 cases of endometritis， 2 first-degree skin burns， 9 cases of hematometria， and 16 cases of vaginitis and/or cystitis. When the authors reviewed the Unite States Food and Drug Administration （FDA） Manufacturer and User Facility Device Experience （MAUDE） database， they found 30 cases of uterine perforation， 8 cases of thermal bowel injuries， and 1 case of necrotizing fasciitis. A total of 85 complications in 62 patients were identified， with 12 patients requiring emergent laparotomy. Although it is difficult to accurately calculate the rates of these occurrences， it is clear that they do occur and that they are under-reported in the literature. The MAUDE database is a collection of all adverse events related to FDA-approved devices. Reports are obtained from industry （when they know of an event）， hospital reporting， or from voluntary reports by individual healthcare providers. Two presentations at the meeting reviewed the available data from the MAUDE database. G. Jardine （University of Utah， Salt Lake City） presented research that he and colleague H.T. Sharp described in an abstract entitled "Global Endometrial Ablation Injuries in 186 Patients and Associated Risk Factors."[2] The MAUDE database was reviewed for the period between January 1998 and April 2005 for all reported adverse events associated with global endometrial ablation devices. Of the 186 injuries reported， 43 were attributed to genital tract burns， 39 to bowel burns， 33 to uterine perforations， 30 to infections， 19 to uterine/cervical scarring， 9 to hemorrhage， 1 to ureteral burn， 1 to uterovaginal fistula， and 11 to other injuries. What is quite remarkable is that many of these adverse events could have been avoided had the device been properly used. The authors believed that 33% of injuries were potentially avoidable. They noted that many patients had preoperative contraindications and that， in a number of cases， there were intraoperative protocol violations or technical errors.
This issue was further elucidated in an abstract presented by A. Atogho （Drexel University College of Medicine， Philadelphia， Pennsylvania） entitled "Serious Adverse Events Associated with the Use of Endometrial Ablation Devices."[3] Once again using the MAUDE database， Atogho and colleagues reviewed cases presenting during the period from January 2003 until December 2004. They noted that 99 patients had an adverse outcome associated with a global endometrial ablation device. The researchers then divided these patients into 2 groups using the narrative report found at the Web site. The adverse event for 54 patients was believed to be associated with out-of-protocol use of the device. Thus， the majority of adverse events were associated with the device being used in a manner that did not conform to the manufacturers guidelines and recommendations. Because of the ease of use of many of these second-generation devices， many more physicians are performing endometrial ablations. In a Cochrane review， Lethaby and colleagues[4] have shown that there are no significant differences between the first-generation endometrial ablation techniques and the second-generation techniques， except for the following： the newer techniques allow a shorter operative time， some of them can be performed under local anesthesia， and they are associated with higher equipment failure rates. In the studies included in the review， the authors found that patients undergoing the newer ablative procedures were less likely to have fluid overload， uterine perforation， cervical laceration， and hematometria than patients undergoing the more traditional type of ablation and resection technique. However， this review included only randomized controlled trials， which are usually carried out by experts in the field and may not accurately represent complication rates that result when the devices are used by the general practitioner.
Although the Cochrane review is somewhat reassuring， these presentations make it clear that although these devices are easy to use， they are not free of complications —— especially if not used properly. The exact number of complications will never be accurately known， but perhaps we can feel somewhat reassured that it is in the range of 0.5-1.2/1000 cases.[1] However， it is my belief that what is reported in the MAUDE database is just the tip of the iceberg， as many cases are never known to the manufacturer or reported by the hospital or physician. Many of these devices have built-in safety mechanisms， but it is incumbent upon the user to understand the instructions for use of any device and to wisely select appropriate patients for this procedure. And finally， physicians should be prepared to address these adverse events promptly should they occur， as delay can lead to catastrophic outcomes.
An interesting side point raised was the issue of cesarean section as a factor for increased risk of complication with global endometrial ablation. Four of the cases presented by Jardine[2] involved thermal injuries associated with cesarean section scars. D.J. Levine （Chesterfield， Missouri） suggested in his presentation[5] that ultrasound evaluation of the myometrial thickness before using second-generation endometrial ablation devices might be beneficial， especially in patients with prior uterine surgery or low transverse cesarean section. Although measuring endometrial thickness may be time-consuming and may not be necessary for most patients， further research is warranted.
Endometrial Ablation Failures
Endometrial ablation is an excellent option for many women who have abnormal uterine bleeding， but this procedure is not successful in all patients. Recent data from the Cochrane review[4] revealed that approximately 5% of women proceed to hysterectomy within 1 year， and as many as 25% have a hysterectomy 5 years out from the procedure. In a large retrospective chart review of their patients， G.A. Vilos （The University of Western Ontario， London， Ontario， Canada） presented data for 174 out of 2860 patients who underwent primary hysteroscopic endometrial ablation over a 13-year period and who went on to hysterectomy at their institute.[6] All patients were ablated hysteroscopically either with resection of the endometrial lining， rollerball endometrial ablation， or a combination of the two. Notably， most failures （67%） occurred within the first 2 years after initial treatment. Pain was the most common indication （82%） for hysterectomy. Adenomyosis was found only in patients with pain and was present in 52% of patients with pain. The exact rate of patients proceeding to hysterectomy could not be calculated for this study because some patients had undergone the procedure at other institutes. Nonetheless， what this study points out is that if pain is a major component of a patients symptoms associated with her bleeding problem， endometrial ablation may not successfully address the pain. It is extremely important to preoperatively assess patients symptoms before offering endometrial ablation. Patients with a significant pain component associated with their abnormal bleeding should be counseled that this procedure might not fully resolve their pain and indeed may increase the likelihood that a secondary procedure will be necessary.
O. Gemer （Barzilai Medical Center， Ashkelon， Israel） presented data on 128 patients who underwent endometrial ablation， 10% （13） of whom failed and required further surgery.[7] Presence of a submucous fibroid was a significant predictor of failure. This again points out the need to properly assess preoperatively， and address intraoperatively， the true pathology causing the abnormal bleeding. One last study presented by A.J. Donovan （Louisville， Kentucky） showed that at 3 years， 6% of women at their center required hysterectomy post endometrial ablation with the hydrothermal ablation system.[8] Pathologic analysis of these hysterectomy specimens confirmed that the majority （66%） had adenomyosis or leiomyomata present.
Pregnancy After Endometrial Ablation
The need for contraception is a concern for both patients and their physicians after endometrial ablation. The reported pregnancy rate after endometrial ablation is quite low， quoted as approximately 0.7%.[9] However， the rate may be significantly higher in younger ovulatory patients. Cook and colleagues[10] reported on 43 pregnancies that occurred after endometrial ablation. These pregnancies were complicated by a high risk of abnormal placentation， spontaneous abortion， preterm delivery， and cesarean hysterectomy. Therefore， consideration must be given to contraception when counseling patients for endometrial ablation. Permanent sterilization is desired by many of these patients， and hysteroscopic sterilization with the Essure system （Conceptus， San Carlos， California） offers a transvaginal approach similar to the endometrial ablation techniques. This has the advantage of being performed at the same time and avoiding an abdominal incision with its inherent risk. To date， the only FDA-approved procedure that can be done after placement of the Essure coils is insertion of the ThermaChoice balloon. Valle and colleagues[11] showed that there is no risk of thermal damage from conduction of heat into the abdominal cavity through the coils and that the balloon was not damaged by the intrauterine portion of the coil.
At this meeting， data were presented regarding the feasibility of performing the Essure procedure after NovaSure （Cytyc Corporation， Palo Alto， California） endometrial ablation. R. Sabbah （Montreal， Canada） presented data indicating that the tubal ostia could reliably be found， and the tubes cannulated， after NovaSure endometrial ablation （N = 18）。[12] M.R. Hopkins （Mayo Clinic， Rochester， Minnesota） noted similar success rates in 16 patients undergoing endometrial ablation.[13] All patients had the devices placed， and to date all patients have had successful occlusion on hysterosalpingogram （HSG）。 These data are reassuring； also reassuring is the fact that HSGs could be successfully performed in all patients without evidence of significant Ashermans syndrome.
In another feasibility trial， presented by C. Dhainaut （Groupe Hospitalier， Bichat-Claude Bernard， Paris， France）， the use of the HydroThermAblator （HTA； Boston Scientific， Natick， Massachusetts） in conjunction with the Essure device was studied.[14] Patients underwent the Essure procedure followed by the HTA technique. Four patients were included， 1 of whom underwent the procedure just before planned hysterectomy. Pathology revealed thermal damage limited to the mucosal layer without reaching the muscularis. This is reassuring. However， there is concern that occlusion may be delayed secondary to thermal damage. In addition， there is the theoretical risk that this device may potentially open the tube initially and allow for leakage of the heated fluid into the abdominal cavity. More research will be required to substantiate the safety of the concomitant use of these 2 procedures.
Conclusion
Endometrial ablation is an excellent option for patients with abnormal bleeding. Appropriate patient selection， preoperative evaluation， and thorough counseling are essential. Newer global endometrial ablation techniques are easier to perform and can be done more quickly. However， their ease of use should not fool the physician. These devices have the capacity to cause great damage if used inappropriately or without adequate understanding of how the device works. Strong consideration must be given to adequate contraception for patients post endometrial ablation. The hysteroscopic approach to sterilization seems to make sense given the similar transcervical approach. Furthermore， both of these procedures can be performed on appropriate candidates in an office setting using minimal anesthesia.
References
1. Gurtcheff SE， Sharp HT. Complications associated with global endometrial ablation： the utility of the MAUDE database. Obstet Gynecol. 2003；102：1278-1282. Abstract
2. Sharp HT， Jardine G. Global endometrial ablation injuries in 186 patients and associated risk factors. JMIG. 2005；12：S8-9.
3. Della Badia CR， Atogho A. Serious adverse events associated with the use of endometrial ablation devices. JMIG. 2005；12：S15.
4. Lethaby A， Hickey M， Garry R. Endometrial destruction techniques for heavy menstrual bleeding. The Cochrane Database of Systematic Reviews 2005， Issue No. 4. Art. CD001501， pub 2. DOI： 10.1002？14651858.CD001501.pub2.
5. Levine DJ. Ultrasound evaluation of the myometrium prior to second generation endometrial ablation. JMIG. 2005；12：S9.
6. Vilos GA， Abu-Rafea B， Ettler HC， Ahmad R. Indications for hysterectomy and uterine histopathology following hysteroscopic endometrial ablation. JMIG. 2005；12：S9.
7. Gemer O， Kruchkovich J， Huerta M， Kapustian V， Kroll D， Anteby E. Perioperative predictors of successful hysteroscopic endometrial ablation. JMIG. 2005；12：S15.
8. Donovan AJ. Analysis of pathology in endometrial ablation failures. JMIG. 2005；12：S59.
9. Pugh CP， Crane JM， Hogan TG. Successful intrauterine pregnancy after endometrial ablation. J Am Assoc Gynecol Laparosc. 2000；7：391-394. Abstract
10. Cook JR， Seman EI. Pregnancy following endometrial ablation： case history and literature review. Obstet Gynecol Surv. 2003；58：551-556. Abstract
11. Valle RF. Concomitant ESSURE tubal sterilization and ThermaChoice endometrial ablation： feasibility and safety. Obstet Gynecol. 2005；105（suppl 4）：6S.
12. Sabbah R， Howell T. Clinical results on feasibility and compatibility of the Essure sterilization immediately following Novasure endometrial ablation. JMIG. 2005；12：S27.
13. Hopkins MR， Famuyide AO， Creedon DJ. Global endometrial ablation using the Novasure radiofrequency device followed by Essure hysteroscopic sterilization. JMIG. 2005；12：S28.
14. Dhainaut C and Bernard BC. Endometrial ablation （EA） utilizing the hydrothermablator （HTA） system in conjunction with tubal sterilization with the Essure device： a feasibility study. JMIG. 2005；12：S27-28.
