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CLINICIAN TO CLINICIAN BY MORRIS WORTMAN, MD, FACOG PRACTICAL ADVICE FRCM COMMUNITY PHYSICIANS Hysteroscopic myomectomy: Pearls and pitfalls from 24 years of practice Hysteroscopic myomectomy continues to evolve with the introduction of new technologies and instrumention. The author discusses his practices and preferences regarding ultrasound guidance, cervical dilation, fluid monitoring, instrumentation, and patient selection based on long experience performing this procedure. S ubmucous l
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  CLINICIAN TO CLINICIAN BY MORRIS WORTMAN MD FACOG PRACTICAL ADVICE FRCM COMMUNITY PHYSICIANS Hysteroscopic myomectomy: Pearls and pitfalls from 24 years of practice Hysteroscopic myomectomy continues to evolve with the introduction of newtechnologies and instrumention. The author discusses his practices and preferencesregarding ultrasound guidance cervical dilation fluid monitoring instrumentation and patient selection based on long experience performing this procedure.   ubmucous leiomyomas measuring less than 4cm, which are generally small enough to permithysteroscopic removal, often announce themselvesby producing menorrhagia, infertility, and pregnancywastage. Although the basic technique of hysteroscopicmyomectomy, introduced by Neuwirth' in 1976, hasremained largely unchanged, the integration of ultrasound(U/S) guidance, strict fluid monitoring, careful cervicalpreparation, and mechanical grasping devices^ can enhancesafety and efficacy while reducing the need for subsequentsurgery. This article reviews both pearls and pitfalls garnered during my 24 years of experience performingmore than 600 hysteroscopic myomectomies. PEARLSPerform diagnostic iiysteroscopyin combination with  U S  guidance There is still controversy regarding the best screeningtool for menstrual disorders, infertility, and pregnancywastage. Some physicians advocate sonohysterography,'whereas others favor diagnostic hysteroscopy. * Both testshave limitations, but together they can provide abundantinformation.Hysteroscopy is not only an important diagnostictool, but it also provides information about the cervix. WE W NT  TO HE R FROM  YOO CUmmii  T CUNICm  offers the hard-wonwisdom and expertise  of  physicians in the trenches. We're looking for unusual case reports, anecdotesahout innovative treatments, and practical solutions for professionai problems fromcommunity physicians.Send your submission  of  1,300 words or fewer to DrLockwood@advanstar.com. Ailsubmissions are subject to peer review by the  Contemporary OB/ßYlil  Editoriai Board.Nevertheless, the concepts discussed may be anecdotal  in  nature. such as the presence of stenosis or its failure to descendwell into the vagina. These are vital preoperativeconsiderations in assessing a patient's candidacy forhysteroscopic myomectomy.^ However, hysteroscopyprovides limited information regarding myoma size,degree of myometrial penetration, or the locationand breadth of its attachment point.^ A simultaneousabdominal U/S examination allows both a panoramicview of the uterine cavity and a sonohysterogram; thelatter provides precise information regarding the size,grade, and location of the myoma and the nature of itsattachment point (Figure 1).'Technically, this combined examination is achievedby first obtaining a clear hysteroscopic view of thecavity while holding the distal lens at the internal os.As an assistant holds the tenaculum, the surgeon placesthe abdominal transducer in both the sagittal andtransverse planes, as necessary, to obtain critical U/Smeasurements. The assistant's other hand allows her tofreeze, measure, and store the images while the surgeonpositions the hysteroscope and U/S probe for optimumviews.This combined procedure not only simulates what thesurgeon may encounter during a subsequent operation,but also enhances the preoperative assessment. Thephysician can thereby provide realistic expectationsfor the patient and plan carefully for instrumentation(Table) and the use of adjuvants, including gonadotropin-releasing hormone (GnRH) analogues and laminaria. Use  U S  guidance  for  hysteroscopic surgery U/S-guided hysteroscopic surgery was reportedindependently by Shalev and Zuckerman' and Lin et al*26 CONTEMPORARYOBGYN.NET  AUGUST 2012  CLINICIAN TO CLINICIAN M I  1  I. I J  I As a noninvasive adjuvant to resectoscopic surgery, U/Sprovides the operator a 3-dimensional understandingof the intrauterine pathology, taking advantage of thedifferent echogenic characteristics of the distendedbladder, myometrium, leiomyomas, and intrauterinedistention ñuid.U/S guidance allows for the safe removal of most grade 2leiomyomas measuring less than 4 cm; it also allows for theresection of cavity-filling myomas by the myoma coring technique' (Figure 2), and the safe use of mechanicalforceps to enhance myoma extraction, a technique firstdescribed by Goldrath.' Goldrath's method can be usedto supplement the standard resectoscopic technique,expediting removal of large quantities of tissue withoutexposing the patient to the risks of  flui ntravasation.Mastering U/S-guided hysteroscopic surgery isfacilitated by working with the same sonographer overtime, beginning with simple cases involving grade 0submucous myomas and progressing to more complexcases.  ombined sonohysterogram  (A)  stablish the  ^ Hysteroscopic myomectomy has often been associated withexcess fluid absorption,^ the results of which can be tragic.The American Association of Gynecologic Laparoscopists(AAGL) has established fluid monitoring guidelines' thatshould be followed carefully. I favor a more stringentprotocol that accounts for the patient's body mass using theformula: MAFA,,v„„=17.6 mL/kg.' Both sets of guidelinesestablish an absolute limit of 1500 mL of low-viscosityanionic distention  flui (LVADF). Provide adequate pressure throughthe fluid management system Adequate visualization allows one to obtain a panoramicperspective of the uterus while avoiding disorientation,inadvertent uterine perforation, and incomplete removalof intrauterine pathology. These goals are dependent onboth adequate intrauterine pressure and sufficient flow.Inexperienced surgeons tend to set fluid pump pressurestoo low, a problem that is fostered by the AAGL fluidmonitoring guidelines, which state that adequatevisualization can generally be obtained with a maximumdelivery pressure of  75  to 100 mm Hg.' * This setting is notbased on randomized controlled trials and, in my opinion, itis often far  elow  what is required for adequate visualizationduring hysteroscopic myomectomy. The practice of settingthe pump pressure below the mean arterial pressure, firstsuggested by Garry et al, makes little practical sense. AsLoffer pointed out, the fluid deficit is the factor that shouldguide the conduct of any case. U/D Flip L R lip ULOliOlf Author's instrumentation for hysteroscopicmyomectomy Instrument 26 or 27F CFR monopolar22F CFR monopolar26F bipolar resectoscopeVasopressin injectionneedleCervical dilatorsForcepsMultiple tenaculaIndicationsUseful for most clinical situationsHelpful in the presence of cervical stenosisFibroids larger than 4 cmMAFA,,„,„ <1000 mL LVADFPatients with an increased rate of fluidabsorptionAllows injection directly into the myoma orits baseLarger forceps may require cervical dilationto  14  or  16 mm Ovum forceps  (7,  10, 12 mm)Scpher forceps  (10,  12,14 mm) Allow management of  an  excessively dilatedcervix Abbreviations: CFR, continuouifluid absorption: LVADF, low-visÏ flow reseotoscope: MAFA,,,,,^,, maximum allowable;cosity anionio distention fluid. I prefer to begin a case with the pump pressure at140 to 180 mm Hg and to decrease it until the infusionpressure is at the minimum level necessary for adequatevisualization. One should remember that the actualintrauterine pressure varies depending on the adjustment AUGUST 2012  CONTEMPORARY OB/GYN 27  CLINICIAN TO CLINICIAN  yoma coring technique  yoma coring technique This sonographically guided technique offers a safeapproach for removing a cavity-fiiiing myoma by reducingits size beginning  t  its core and systematically workingtoward the periphery. of  the  outflow port  of the  resectoscope. High pumppressures translate into high intrauterine pressures onlywhen  the  outflow valve  is  shut, which  is an  uncommonsituation during resectoscopic surgery. Understand the critical importance ot cervical dilation Hysteroscopic myomectomy requires  a  well-dilatedcervix  to  allow  the  easy introduction, removal,  and reintroduction  of a  resectoscope,  an  important  and oft repeated sequence  in  hysteroscopic myomectomy.  In  fact,cervical stenosis may be  a  relative contraindication to  the removal of all but the smallest myomas.Inadequate cervical preparation may result  in  forcefuldilation and excessive traction on the cervical tenaculum.The former increases  the  risk  of  uterine perforation  and endocervical lacerations,  and the  latter increases  the risk  of  ectocervical lacerations. Cervical dilation  can be enhanced with  the use of  intravaginally administeredmisoprostol or  the placement of  a  3-  to  4-mm laminariajapónica the afternoon before surgery.  In  most instances,these adjuvants permit  the  easy introduction  of  a 9-mmresectoscope  the  following  day  with minimal dilatoryeffort. Dilatory forces  can be  further reduced  by intracervical injection  of  vasopressin. My practice  is to inject vasopressin, 2.5 units diluted  in  20 mL of saline,  to a depth  of   to 4  cm into the cervical stroma  at  the 3-  or 9-o'clock positions. Abdominal probe 3.5 MHz)LeiomyomaPosterioruterine wall180 wire loop In other instances,  the  cervix may  be  patulous  and overdilated. This results  in  unwanted egress  of  distentionfluid, resulting  in  poor uterine distention, inadequatevisualization, and disorientation; these conditions  in  turnincrease the risk  of  accidental perforation and incompletemyoma removal. This condition  is  easily managed  by sequential placement  of  tenacula  at the 3 and  9-o'clockpositions until  an  adequate seal develops between  the resectoscope and the cervical os. Use appropriate instrumentation The Table summarizes  my  preferred instrumentsand their indications. Operative hysteroscopes  for myomectomy include both electrosurgical resectoscopesand  the  newly available mechanical hysteroscopicmorcellators.  The  latter  are not  well studied  and I have little experience with them. Although  a 9 mm unipolar resectoscope will suffice  for  most hysteroscopicmyomectomies, cervical stenosis  may  require  the use of  a  smaller  7 mm  resectoscope  or a  small-diameterhysteroscopic morcellator. Other instruments, such  as the hysteroscopic injection needle, mechanical forceps,cervical dilators,  and  multiple tenacula,  are  useful  to manage an array of clinical scenarios.Electrosurgical resectoscopes  are  available  as  bothunipolar  and  bipolar models. The former  are  generallyoffered  in a 9 and a  7-mm version. Unipolar systems 28 CONTEMPORARYOBGYN NET  AUGUST 2012  CLINICIAN TO CLINICIAN provide excellent cutting and coagulation with a sturdyelectrode that does not easily deform or fracture;however, these require an LVADF and a MAFA;,-„„ thatare more restrictive compared with normal saline.Significant cervical stenosis often requires the use of a7-mm resectoscope, which results in longer operativetimes because the smaller 19F electrosurgical loopremoves less tissue.Bipolar resectoscopes are helpful in patients with alow body mass, requiring one to carefully limit the use ofLVADF, or with large or multiple myomas, for which longresection times are anticipated. The use of normal salinefor distention with bipolar instruments allows greaternet fluid absorption; this reaches 2,500 mL in mostcases.' One shortcoming of bipolar systems is that theyprovide relatively poor tissue coagulation compared withunipolar systems. In a unipolar system, the coagulationcurrent travels through the tissue to a ground plate.That same current also travels through the area of leastimpedance, along blood vessels that run perpendicularto the surface of the uterus or myoma. In a bipolarsystem, the current returns to a negative electrode about1 cm away (located on the resectoscope). In vivo modelshave demonstrated that the temperatures reached inunipolar systems and the resulting tissue penetrationis greater than what can be achieved with bipolarsystems. For this reason, I prefer to use a 9-mm unipolarresectoscope for the vast majority of cases.You may begin a case with unipolar electrosurgery andtransition to a bipolar system, provided that you adhereto the fluid management guidelines of both systems.' Thispractice often allows completion of a procedure once the MAFA v„„  of  LVADF  has been reached.'»When the pedicle can be clearly visualized, directinjection of vasopressin helps reduce bleeding duringthe hysteroscopic myomectomy. The same dilution ofvasopressin used for intracervical injection is employed.The total amount of vasopressin should not exceed 5units in 40 minutes. I prefer to use a 40 cm x 21-gauge Ginjection needle (Vita Needle Company, Needham, MA),which is passed down the operative port of a standard26-F resectoscope.In 1990, Goldrath^ described the technique of vaginal myomectomy, which involved the insertion oflaminaria tents to accomplish cervical dilation and theblind removal of leiomyomas using various forceps. In hisseries of  151  patients, the hysterectomy avoidance rate was 92%  and there were 2 uterine perforations (1.3%). Withthe use of  U/S  guidance, this technique need no longer beperformed blind. Provided the cervix is well dilated, thereare 3 clear advantages to this technique. First, it obviates POWER POINTSHysteroscopicmyomectomyrequires an arrayof instrumentationto accommodatea variety ofintraoperativescenarios the need for any distention media and thereby precludesthe issues associated with excess fluid absorption.Second, the procedure is extremely efficient; well-selectedleiomyomas can be removed quickly provided that theyare pedunculated grade 0 leiomyomas that have beenreduced to less than 3 cm. Third, the procedure eliminatesthe need for relatively expensive uterine morcellators.The major risks of this procedure are 2-fold. First,uterine perforation is still possible in inexperiencedhands. Second, in some circumstances the combinationof the myoma and grasping forceps cannot be deliveredthrough the endocervical canal, precluding removal ofthe instrument or the fibroid. Toprevent this occurrence, one shouldbe able to disarticulate all graspingforceps used for this purpose at theirfulcrum. Surprisingly large fibroidscan be removed in this fashion(Figure 3).Small flexible dilators such asCooper Surgical os finders are oftenhelpful in managing marked ormoderate cervical stenosis. Theirflexible tip helps avoid inadvertentperforation. Routine dilation to 9 mm is best performedwith Hegar dilators, which have a short dilating surfacethat also helps avoid uterine perforation, a concern witha short, very anteflexed, or retroflexed uterus. Whengreater dilation is necessary, for example with the use ofmechanical forceps, large-diameter Hegar dilators (up to16 mm) or Denniston dilators (up to 14 mm) should beinserted under sonographic guidance.As already noted, I often use multiple tenacula to limitunwanted fluid egress between the resectoscope andthe cervix. The placement of tenacula is similarly usefulafter mechanical forceps are used to extract a submucousleiomyoma. Consider administration of GnRH analogues Selective use of a GnRH analogue may enhance thefeasibility and safety of hysteroscopic myomectomy,particularly for myomas larger than 4 cm. Crosignani et al reported that use of a GnRH analogue before surgeryfor uterine leiomyomas produced a temporary 40% to 50%  reduction in mean uterine volume. Perino et al *observed a  35.1%  reduction in operative time along with amarked improvement in procedure completion rates withthe use of leuprohde acetate depot. I have observed similaradvantages using leuprolide depot 3.75 mg (Lupron Depot;Abbott Laboratories, Abbott Park, Illinois) for 2 monthsbefore surgery. AUGUST 2 12  CONTEMPORARY OB GYN 29
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