OBJECTIVE: To describe the variations in the location of the vaginal apex and the length of vagina excised in women undergoing the Michigan four-wall sacrospinous suspension for posthysterectomy vaginal vault prolapse.
METHODS: A prospective observational study of 76 women who had the Michigan modification sacrospinous suspension performed between 1998 and 2001 for posthysterectomy vaginal vault prolapse was carried out. Demographics and preoperative, operative, and postoperative findings were noted, including the pelvic organ prolapse quantification score. The locations of the suspension points relative to the hysterectomy scar were recorded. The amount of vagina excised at surgery and the pre- and postoperative vaginal lengths are reported.
RESULTS: The mean length and standard deviation of vagina excised was 4.6 ± 2.5 cm. The apex created at sacrospinous fixation was at the hysterectomy scar in only seven women (9%). It was most often situated behind the hysterectomy scar, in 58 cases (76%); it was situated in front of it in 11 (14%). In seven women no vagina was excised, and in the remaining 69 women a mean length of 5.1 ± 2.2 cm was removed. The mean vaginal lengths were 9.7 ± 1.7 cm preoperatively and 9.4 cm ± 0.8 postoperatively, a 0.3-cm difference.
CONCLUSION: When one performs the Michigan modification sacrospinous suspension, the chosen suspension points are often not at the hysterectomy scar, and in women with large prolapses excess vagina frequently is excised without compromising postoperative vaginal length.
The apex created at the Michigan modification sacrospinous suspension is often not at the hysterectomy scar.
Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, Michigan.
Address reprint requests to: John O. L. DeLancey, MD, University of Michigan, Department of Obstetrics and Gynecology, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0276; E-mail: firstname.lastname@example.org.
Received March 4, 2002. Received in revised form June 12, 2002. Accepted August 1, 2002.
Sacrospinous suspension is an established technique successful in treating vaginal vault eversion.1–6 Proper selection of the points on the vagina to be suspended is critical. A point on the vaginal wall too near the introitus may not allow the selected length of vagina to reach the ligament, resulting in a suture bridge. Selecting a point on the vagina too far from the introitus results in too long a length of suspended vagina that may continue to prolapse after suspension.
The place on the sacrospinous ligament to which the vagina will be suspended averages about 9 cm from the vaginal introitus. In women with a large vaginal prolapse the vagina is often substantially longer than this distance. In this situation, simply attaching the posterior vaginal wall to the sacrospinous suspension does not always lead to satisfactory suspension of the anterior or lateral vaginal walls.
To avoid sagging or redundancy in both the anterior and the posterior walls, it would seem best to choose points on each of these walls that are the same distance from the ligament as the distance between the introitus and ligament. Although the traditional sacrospinous ligament suspension attaches only the posterior vaginal wall to the ligament, it is possible to also attach the anterior and lateral vagina as we have done.6 In a large prolapse, this involves removing redundant vaginal wall between the suspension points to avoid sagging (Figure 1), and this is the focus of the Michigan four-wall sacrospinous ligament suspension.6
There are substantial variations in the amount of vaginal wall that needs to be excised and whether this excised vagina is in front of or behind the hysterectomy scar. This study reports on a prospective analysis of the amount of redundant vagina, its relationship to the prior hysterectomy scar, and preoperative and postoperative vaginal lengths.
MATERIALS AND METHODS
A prospective observational study of 76 women with posthysterectomy vaginal vault eversion who had the Michigan modification of the sacrospinous suspension done by the senior author between 1998 and 2001 was performed. Data collected included demographics, pre-operative examination, intraoperative measurements, and postoperative findings.
The age, parity, height, and weight of the 76 women are shown in Table 1. The median number of operations previously performed for pelvic organ prolapse in these women was one, with a range of zero to three. Seventeen women had no previous prolapse surgery, 42 women had one previous operation for prolapse, and 17 women had more than one previous prolapse surgery. Four patients had failed previous vault suspension procedures—two traditional sacrospinous fixations and two abdominal sacral colpopexies.
At the preoperative visit the standardized pelvic organ prolapse quantification score was used to measure the prolapse.7 In this system measurements were made of the location of predefined points along the anterior and posterior vaginal walls relative to the hymenal ring. Negative values lie cephalad to the hymen and positive values caudad. Point Aa is 3 cm from the hymen on the anterior wall, and point Ba is the most dependent point on the anterior wall above this point. Points Ap and Bp are analogous points on the posterior wall. Point C is the cervix, or hysterectomy scar. This was modified in that the genital hiatus measurements were taken at rest to assess levator hiatus area separate from the distending effect of the prolapse, as has been our practice8 (Table 2).
The most dependent point on the Pelvic Organ Prolapse Quantification score was taken to be the site of maximum prolapse. This had a mean value of 4.6 ± 2.6 cm below the hymen.
The surgical technique used has previously been described.6,9 In brief, it involves identifying the point on each vaginal wall (anterior, posterior, and lateral) that comfortably reaches the ligament yet eliminates sagging. The intervening vagina is then removed. To begin, a point on the anterior vaginal wall that is estimated to be the same distance from the introitus as the distance to the ligament is grasped with an Allis forceps (Figure 2). To test for proper clamp placement and avoid removing too much or too little vagina, the tip of the clamp and its included vagina are elevated to the sacrospinous ligament to confirm that this point on the vaginal wall reaches the ligament comfortably. If the proper length of vagina has not been identified—that is, the vagina is too tight or too loose—the position of the clamp is adjusted until proper placement is achieved. A similar point is then chosen and confirmed on the posterior and both lateral vaginal walls. The intervening tissue between these points is then excised. A right unilateral sacrospinous suspension is then performed by using previously placed sutures in the sacrospinous ligament to sew the anterior and posterior margins of this open cuff to the ligament.
During these operations, the amount of vaginal wall to be removed is measured as the distance between the clamps (Figure 2), before excision, to the nearest centimeter. In addition, the location of the hysterectomy scar relative to these points is also measured. Postoperatively a Pelvic Organ Prolapse Quantification score is again recorded, which includes a vaginal length measurement. The postoperative exam was performed by one of the two authors. The postoperative measurements were made at 1-year review in 47 women and at the 6-week postoperative visit in 29 women.
Statistical analysis was carried out using Statview statistical software (Abacus Concepts, Berkeley, CA). The relationship between preoperative vaginal length and the amount of vagina excised at surgery was assessed by calculating the correlation coefficient between these measures. The relationship between the length of vagina excised and the preoperative vaginal length was also calculated. The difference between the preoperative and postoperative Pelvic Organ Prolapse Quantification measurements was analyzed with the paired t test.
The mean length of vagina excised in the anterior-posterior direction was 4.6 ± 2.5 cm. In seven women no vagina was excised, and in the remaining 69 women a mean length of 5.1 ± 2.2 cm was removed. In 23 women 6 cm or more of vagina was excised, and in three women, 10 cm or more. The mean transverse diameters removed were similar, averaging 4.1 ± 2.2 cm. The other operations performed at the time of the sacrospinous suspension are shown in Table 3.
The relationship of the excised vagina to the hysterectomy scar is shown diagrammatically in Figure 3, and the results of this excision are displayed in Figure 4. A positive value denotes measurements where the center of the excised vagina was in front of the hysterectomy scar, and a negative value denotes measurements where it was behind the scar.
The apex created at sacrospinous fixation is at the center of the excised vagina. It was at the hysterectomy scar in only seven women (9%). It was most often situated behind the hysterectomy scar, in 58 cases (76%), and it was in front in 11 cases (14%).
As expected in women with a large prolapse before surgery, the vagina was longer than it was in women with a smaller protrusion. Thus, the size of the prolapse, as determined by the distance below the hymen of the most dependent Pelvic Organ Prolapse Quantification point, was correlated with preoperative vaginal length (r = .697, P < .001) The preoperative vaginal length also correlated with the amount of tissue excised at surgery (r = .747, P < .001). Those women with a longer vagina had more vaginal length excised. Mean vaginal lengths were 9.7 ± 1.7 cm preoperatively and 9.4 cm ± 0.8 cm postoperatively, a 0.3-cm difference (P = .30). The shortest vagina recorded postoperatively was 8 cm.
Experienced surgeons have recognized the wide variety of anatomic situations found among women with pelvic organ prolapse. Tailoring the operative procedure to address each woman's clinical situation is the key to achieving a good outcome. This report quantifies the variations in the location of the vaginal apex and the degree of excess vaginal length present in women with posthysterectomy vaginal vault prolapse. It specifically identifies the variations in the location of the suspension points relative to the hysterectomy scar.
The location of the hysterectomy scar varied widely relative to the suspension points. In only 9% of women was the middle of the new apex at the site of the hysterectomy scar. In the majority of cases (76%) it was behind the scar. In 57% the hysterectomy scar was not even within the area of the new apex. This indicates that it should be the distance to the ligament that decides the location of the suspension points on the vaginal walls, rather than relying on the location of the hysterectomy scar to determine where the suspension should be carried out. This sometimes results in a normal vaginal wall's fibromuscular layer being removed, but avoiding this would often result in unsatisfactory suspension and continued sagging of the vagina.
In women with a large prolapse there was often a considerable amount of excess vagina, and there was a strong correlation between the preoperative vaginal length and the amount of vagina excised. Interestingly, the pre- and postoperative lengths in these women were similar despite the excision of substantial amounts of vagina. The mean postoperative vaginal length is 9.4 cm, compared with a mean preoperative vaginal length of 9.7 cm. This seems unexpected in light of the fact that many centimeters were excised in individual women. The relatively modest change in average length is attributable to the fact that the vast majority of women had a normal vaginal length preoperatively (median 9.5 cm) and that those requiring large amounts of excision were in the minority, although critically important. This emphasizes the importance of individualizing the treatment for each woman. We feel it would not be wise to excise vagina in a woman whose vagina is 8 cm, nor would it be prudent not to excise vagina in a woman with an 18-cm vagina.
However, it is important to realize that vaginal length does not seem to correlate well with postoperative sexual function.10 One study of a series of 165 women having surgery for prolapse or incontinence looked at vaginal length measurements and sexual function. The authors found a statistically significant change in both vaginal length and caliber after surgery, but failed to show a significant correlation between these changes and sexual function.11 We have not found sexual dysfunction to be common in our patients6 and do not feel that excising vagina when necessary leads to sexual dysfunction. In a report of 100 cases of women undergoing sacrospinous suspension at this institution four women had vaginal stenosis, three requiring treatment.6 All of these women had had prior anterior-posterior repair. Excising vagina normalizes vaginal length, taking a gaping and enlarged vagina when present and returning it to a more normal size.
The efficacy and low complication rate of this procedure when performed by experienced surgeons have been described in published reports.2,3 Concerns about the occurrence of anterior wall prolapse have limited the current popularity of the procedure. The incidence of reported cystocele after this procedure varies from 1.3% to 92%.2,3,12–15 This long-known problem of the asymptomatic cystocele, we feel, is minimized though not eliminated by choosing an appropriate anterior suspension point. The position of our postoperative anterior points (Aa and Ba) in this study at − 1.3 and − 1.2 may at first seem below an expected position. However, this must be seen in the context of findings in nonprolapse gynecology patients, where the vaginal wall descends between − 1 or greater and +1 or less (“stage II”) in over 50% of parous women.16 We have previously reported on our outcome and complications in a series of 100 women who had the Michigan modification sacrospinous suspension. At 1-year follow-up 70% of women have normal support, with a further 20% having an asymptomatic mild vaginal wall relaxation, not below the hymen. A further report suggests that performing a sacrospinous suspension does not independently increase the risk of cystocele development.17
The purpose of this study was to report on the location of the suspension points and the variations in excised vagina. Future research will focus on quality of life issues.
1. Nichols DH. Sacrospinous fixation for massive eversion of the vagina. Am J Obstet Gynecol 1982;142:901–4.
2. Porges RF, Smilen SW. Long-term analysis of the surgical management of pelvic support defects. Am J Obstet Gynecol 1994;171:1518–26.
3. Paraiso MF, Ballard LA, Walters MD, Lee JC, Mitchinson AR. Pelvic support defects and visceral and sexual function in women treated with sacrospinous ligament suspension and pelvic reconstruction. Am J Obstet Gynecol 1996; 175:1423–30.
4. Carey MP, Slack MC. Vaginal vault prolapse. Br J Hosp Med 1994;51:417–20.
5. Carey MP, Slack MC. Transvaginal sacrospinous colpopexy for vault and marked uterovaginal prolapse. Br J Obstet Gynaecol 1994;101:536–40.
6. Morley GW, DeLancey JOL. Sacrospinous ligament fixation for eversion of the vagina. Am J Obstet Gynecol 1988;158:872–81.
7. Bump RC, Mattiasson A, Bo K, Brubaker LP, DeLancey JOL, Klarskov P, et al. The standardization of terminology of female pelvic organ prolapse and pelvic floor dysfunction. Am J Obstet Gynecol 1996;175:10–7.
8. DeLancey JOL, Hurd WW. Size of the urogenital hiatus in the levator ani muscles in normal women and women with pelvic organ prolapse. Obstet Gynecol 1998;91:364–8.
9. DeLancey JO, Morley GW, Howard D. Sacrospinous suspension: Michigan 4-wall offers better support. Obstet Gynecol Management 2001Mar;18–29.
10. Weber AM, Walters MD, Schover LR, Mitchinson A. Vaginal anatomy and sexual function. Obstet Gynecol 1995;86:946–9.
11. Weber AM, Walters MD, Piedmonte MR. Sexual function and vaginal anatomy in women before and after surgery for pelvic organ prolapse and urinary incontinence. Am J Obstet Gynecol 2000;182:1610–5.
12. Sze EH, Kohli N, Miklos JR, Roat T, Karram MM. A retrospective comparison of abdominal sacrocolpopexy with Burch colposuspension versus sacrospinous fixation with transvaginal needle suspension for the management of vaginal vault prolapse and coexisting stress incontinence. Int Urogynecol J 1999;10:390–3.
13. Benson JT, Lucente V, McClellan E. Vaginal versus abdominal reconstructive surgery for the treatment of pelvic support defects: A prospective randomized study with long-term outcome evaluation. Am J Obstet Gynecol 1996;175:1418–21.
14. Bump RC, Hurt WG, Theofrastous JP, Addison WA, Fantl JA, Wyman JF, et al. Randomized prospective comparison of needle colposuspension versus endopelvic fascia plication for potential stress incontinence prophylaxis in women undergoing vaginal reconstruction for stage III or IV pelvic organ prolapse. The Continence Program for Women Research Group. Am J Obstet Gynecol 1996;175:326–33.
15. Holley RL, Varner RE, Gleason BP, Apffel LA, Scott S. Recurrent pelvic support defects after sacrospinous ligament fixation for vaginal vault prolapse. J Am Coll Surg 1995;180:444–8.
16. Swift SE. The distribution of pelvic organ support in a population of female subjects seen for routine gynecologic health care. Am J Obstet Gynecol 2000;183:277–85.
© 2003 The American College of Obstetricians and Gynecologists
17. Smilen SW, Saini J, Wallach SJ, Porges RF. The risk of cystocele after sacrospinous ligament suspension. Am J Obstet Gynecol 1998;179:1465–71.