To the Editor:
Paolo Casadio et al. recently published an interesting paper focusing on the dynamic changes of the myometrial free margin separating type II submucous fibroids from the serosa during hysteroscopic resection (1). Although the number of patients of this prospective observational study is limited (n = 13), the authors interestingly concluded that “myometrial free margin increases progressively with each step of the procedure probably leading to an increasing margin of safety.” This study updates and reinforces the previous observation by Yang et al., which first demonstrated that the myometrial free margin is not a static parameter but it “increased gradually after each step of the resection, reaching its maximum after the completion of the procedure” (2). They observed the progressive thickening of myometrium at transabdominal sonography while the myoma is progressively enucleated, suggesting two possible mechanism for this phenomenon: the reshaping of the distended uterine myometrial fibers and the contractions induced by electrosurgery and the myoma grasping by forceps.
In the last decade, my group and I extensively focused on this topic by standardizing the classification of submucous myomas using 2D and 3D saline contrast sonohysterography (3). During 2D saline infusion, the dynamic changes of the myometrial free margin could be easily observed (see the video-clip).
Also, we investigated the intraoperative changes of the myometrium during hysteroscopic myomectomy performed by the combined use of electrical monopolar and “non-electrical” cold loops (unpublished data). By repeated traction maneuvers on the myoma and continuous intrauterine pressure changes obtained by the use of inflow and outflow stopcocks, results similar to the above-reported were observed, but in presence of adjacent coexisting intramural and/or subserous myomas.
In our recently accepted paper on hysteroscopic myomectomy on 169 hysteroscopic procedures for type I and type II submucous fibroids, we reported one uterine perforation (4). It occurred in a case of a type II 3-cm submucous myoma, with a 5-mm myometrial free margin, located near a 3-cm intramural-subserosal fibroid. During the cold-loop enucleation, at the end of the removal of the deep intramural part, a uterine perforation occurred because of the loss of the described progressive myometrial contraction. Because of the cold loop’s use, no further surgery was needed and clinico-sonographic monitoring was successfully applied.
This episode confirmed the indication by Perrot et al., which suggested the presence of co-existing adjacent myomas as a risk factor for uterine perforation (5).
To sum up, I do absolutely agree with the data reported by Casadio et al., which should reassure and strengthen the confidence of the hysteroscopist in the treatment of type II myoma. Furthermore, I would stress the need of a proper presurgical sonographic evaluation and consideration of the presence of co-existing adjacent myomas as a risk factor for uterine perforation (Figure 1), because of sliding and the reduced contraction and thickening of the myometrial free margin.
Francesco P.G. Leone, M.D.
Department of Obstetrics and Gynecology
Clinical Sciences Institute L. Sacco
University of Milan
1. Casadio P, Youssef AM, Spagnolo E, Rizzo MA, Talamo MR, De Angelis D, Marra E, Ghi T, Savelli L, Farina A, Pelusi G, Mazzon I. Should the myometrial free margin still be considered a limiting factor for hysteroscopic resection of submucous fibroids? A possible answer to an old question. Fertil Steril. 2011 Apr;95(5):1764-1768.
2. Yang JH, Lin BL. Changes in myometrial thickness during hysteroscopic resection of deeply invasive submucous myomas. J Am Assoc Gynecol Laparosc 2001;8:501–5.
3. Leone FP, Bignardi T, Marciante C, Ferrazzi E. (2007) Sonohysterography in the preoperative grading of submucous fibroids: considerations on three-dimensional methodology. Ultrasound Obstet Gynecol 29:717–718.
4. Leone FP, Calabrese S, Marciante C, Cetin I, Ferrazzi E. Feasibility and long-term efficacy of hysteroscopic myomectomy for myomas with intramural development by the use of non-electrical “cold” loops. Gynecol Surg., DOI: 10.1007/s10397-011-0706-4
5. Perrot N, Mergui JL, Frey I, Uzan M. Menorrhagia after age 40. Contribution of ultrasonic examination. Gynecol Obstet Fertil. 2002 Jun;30(6):523-31.
Published online in Fertility and Sterility doi:10.1016/j.fertnstert.2011.10.029
The Authors Respond:
We would like to thank Dr. Leone for his comment. His experience and observations on the resection of submucous fibroids are extremely interesting and address some important issues which undoubtedly need further evaluation by other studies.
It is important to point out the dynamic nature of the myometrial free margin. We believe that both safety and success of submucous myoma resection are strictly dependent upon this feature. We agree with Dr. Leone that this change is not expected to be similar in all women and that it may be affected by several factors.
Dr. Leone has stressed the importance of the presence of adjacent multiple fibroids. He mentioned that in the only case of uterine perforation in his series, an adjacent intramural-subserosal fibroid was present close to the fibroid removed.
Unsurprisingly, he has described a loss of the progressive myometrial contraction in this specific case. Although in our study we included only cases with single fibroids (1), our experience is in line with his data. Together with the alteration of myometrial contractility, we think that the presence of an adjacent fibroid may further increase the technical difficulty of hysteroscopic resection through an increased difficulty in finding a clear plane of cleavage. For this reason an adequate detailed pre-operative sonographic fibroid evaluation of fibroids’ number, location (anterior/posterior, fundal/isthmic/angular), depth, dimensions, morphology (contour, unilobed/bilobed) and shape may allow safe and successful hysteroscopic fibroid resection.
Other important factors which may have an impact on the intraoperative myometrial response to resection may include age, parity, previous uterine surgeries, and medical therapies (e.g., administration of GnRH analogues). We believe that these factors may significantly alter the normal contractility of the normal myometrial fibers surrounding the fibroid, thus affecting both the success and complication rates. With adequate consideration of several parameters, women may be offered proper preoperative counseling prior to undergoing hysteroscopic fibroid resection (2).
Further data are clearly needed in order to better correlate preoperative ultrasound parameters and patient characteristics with myometrial behavior, possibly leading to a better evaluation of success and complication probability prior to resectoscopic resection of submucous fibroids.
Paolo Casadio, M.D.
Aly Youssef, M.D.
Luca Savelli, M.D.
Tullio Ghi, M.D.
Emanuela Spagnolo, M.D.
Francesca Guasina, M.D.
Renato Seracchioli, M.D.
Department of Obstetrics and Gynecology
S. Orsola Malpighi University Hospital
University of Bologna
1. Casadio P, Youssef AM, Spagnolo E, Rizzo MA, Talamo MR, De Angelis D, Marra E, Ghi T, Savelli L, Farina A, Pelusi G, Mazzon I. Should the myometrial free margin still be considered a limiting factor for hysteroscopic resection of submucous fibroids? A possible answer to an old question. Fertil Steril 2011; 95:1764-8.
2. Mavrelos D, Naftalin J, Hoo W, Ben-Nagi J, Holland T, Jurkovic D. Preoperative assessment of submucous fibroids by three-dimensional saline contrast sonohysterography. Ultrasound Obstet Gynecol 2011; 38: 350-4.
Published online in Fertility and Sterility doi:10.1016/j.fertnstert.2011.10.030