Estimated levator ani subtended volume: a novel assay for predicting surgical failure after uterosacral ligament suspension

Estimated levator ani subtended volume: a novel assay for predicting surgical failure after uterosacral ligament suspension

Original Research 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 ...

634KB Sizes 0 Downloads 35 Views

Original Research 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

ajog.org

UROLOGY

Estimated levator ani subtended volume: a novel assay for predicting surgical failure after uterosacral ligament suspension Q15

Q1

Allison M. Wyman, MD; Antonio A. Rodrigues Jr, MD, PhD; Lindsey Hahn, DO; Kristie A. Greene, MD; Renee Bassaly, DO; Stuart Hart, MD, MBA; Branko Miladinovic, PhD; Lennox Hoyte, MD, MSEE/CS

BACKGROUND: Levator ani muscle complex plays an important role

Q2

in pelvic support and defects or laxity in this muscle complex contributes to pelvic organ prolapse and recurrence after surgical repair. OBJECTIVE: The purpose of this study was to determine whether estimated levator ani subtended volume can predict surgical outcomes for laparoscopic bilateral uterosacral ligament suspension. STUDY DESIGN: A retrospective cohort study was performed in patients who underwent laparoscopic uterosacral ligament suspension from 2010-2012. Only patients with a preoperative pelvic magnetic resonance image were included. Surgical failure was defined as a composite score that included the presence of anatomic bulge beyond the hymen with sensation of vaginal bulge or repeat treatment for prolapse via pessary or surgery by 1-year follow-up evaluation. Standard protocol pelvic magnetic resonance imaging measurements pubococcygeal line, H-line, and M-line were collected along with the calculation of the width of the levator ani hiatus. Estimated levator ani subtended volume was calculated for each subject. An optimal cutoff point was calculated and compared against categoric values of surgical success/failure. A Fisher exact test, an area under receiver operating characteristics curve, and logistic regression analysis were performed. A probability value of <.05 was considered statistically significant. RESULTS: Ninety-three women underwent laparoscopic bilateral uterosacral ligament suspension during study period. Of these, 66 women had a standardized preoperative pelvic magnetic resonance image per

A

pproximately 200,000 women will undergo a surgical procedure for pelvic organ prolapse (POP) in the United States each year, with projections of this number expected to double within the next 30 years.1,2 Additionally, 1 of 6 of these women will undergo a second surgery for recurrence of prolapse.3 Although the pathogenesis of POP is multifactorial, childbirth and Cite this article as: Wyman AM, Rodrigues Jr AA, Hahn L, et al. Estimated levator ani subtended volume: a novel assay for predicting surgical failure after uterosacral ligament suspension. Am J Obstet Gynecol 2016;:. 0002-9378/$36.00 ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog.2015.11.005

institutional protocol. Thirteen patients (19.6%) met the criteria for surgical failure by 1 year. An optimal cutoff point of 38.5 was calculated by Liu’s method for optimization. Among the patients with defined surgical failures, 84.6% (11/13) had an estimated levator ani subtended volume above cutoff point of 38.5. Among the patients with defined surgical success, 39.6% (21/53) had an estimated levator ani subtended volume above the cutoff point (84.6% vs 39.6%; P ¼ .0048) with a significant odds ratio of 8.38 (95% confidence interval, 1.69e41.68; P ¼ .009). An area under receiver operating characteristics curve of 0.725 (95% confidence interval, 0.603e0.847), sensitivity of 84.6% (95% confidence interval, 54.6% e98.1%), and specificity of 60.4% (95% confidence interval, 46% e73.5%) at 38.5 were predictors of surgical success/failure by 1 year. Logistic regression analysis demonstrated no significant confounders among age, body mass index, stage, or parity. CONCLUSIONS: Estimated levator ani subtended volume may predict surgical failure for laparoscopic bilateral uterosacral ligament suspension. Patients with a calculated estimated levator ani subtended volume above 38.5 on a preoperative pelvic magnetic resonance imaging were associated with an increased risk for surgical failure by 1 year, regardless of age, body mass index, stage, or parity. Future investigation that will include repeatability, reliability analysis, and a prospective study is warranted.

Q3

Key words: levator ani muscle, levator ani subtended volume, magnetic resonance imaging, pelvic organ prolapse, surgical outcome

vaginal parity have been identified as strong risk factors for the development of POP.4,5 More than 30% of women who deliver vaginally will have direct trauma to their pelvic floor that will result in injury to the levator ani muscle.5 Pelvic magnetic resonance imaging (MRI) and ultrasonography both independently have demonstrated pelvic floor trauma in women after childbirth.6-8 Avulsion of the levator ani muscle from insertion points on the inferior aspect pubic bone that resulted in weakening of the muscle complex was detected in 15-36% of parous women on pelvic MRI and ultrasound images.6-8 The levator ani muscle encircles the largest potential hernia portal in the

human body and is the gatekeeper for passage of pelvic organs resulting in POP.9 Weakening of this muscle complex is currently the best-defined pathogenesis for POP.9 Strong correlations have demonstrated enlargement of this portal within the levator ani muscles to be related directly to the presence of POP.5,10 Studies have confirmed levator ani avulsion as a risk factor for the development of POP.11,12 Women with levator ani avulsions that were detected on pelvic MRIs had a 7.3 odds ratio (OR) for POP when compared with a matched control group.11 Additionally, levator ani avulsion has been demonstrated to be a clinical predictor of cystocele recurrence after anterior colporrhaphy with native

MONTH 2015 American Journal of Obstetrics & Gynecology FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

1.e1

Q4

56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110

Original Research 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166

ajog.org

UROLOGY

tissue and anterior colporrhaphy with the usage of mesh.13,14 Levator ani muscle morphologic condition that was demonstrated with pelvic 3-dimensional MRI images established a relationship between the size and shape of the entire muscle complex to pelvic floor dysfunction and prolapse.15 Women with advanced-staged POP demonstrated increased laxity of the muscle complex that altered the anatomic shape of the muscle and correlated to worsening pelvic floor dysfunction.15 Anatomic changes in the levator ani muscle complex that result in weakening of the pelvic floor are described in DeLancey’s16 and Norton’s17 “boat in a dry dock” theory. We applied DeLancey’s and Norton’s theory for our hypothesis that decreased support of the levator ani muscle within the pelvic floor will result in an increased strain on the supportive uterosacral ligaments after a laparoscopic bilateral uterosacral ligament suspension (USLS) and result in increased risk of recurrence for POP after pelvic reconstructive surgery. The aim of this study was to assess the utility of standard protocol preoperative pelvic MRIs to evaluate levator ani muscle integrity for the prediction of surgical outcomes after an apical reconstructive surgical procedure. Rodrigues et al18 developed a reliable objective measure of levator ani muscle laxity using a 3-dimensional MRI pelvic measurement defined as levator ani subtended volume (LASV). LASV is an objective measure of volume held within a levator ani muscle complex. Consider the muscle complex as a kitchen bowel that is filled with water; LASV is the measurement of the volume of the water. Their group further developed a simplified method for estimating LASV (eLASV) from standard 2-dimensional MRI measurements as an indirect measurement of the volume that is contained by the levator ani muscle.19 In this study, we sought to determine whether eLASV can predict surgical outcomes for laparoscopic bilateral USLS.

Materials and Methods This was an Institutional Review Boardeapproved retrospective cohort

study at a tertiary care center, University of South Florida, of all patients who underwent laparoscopic bilateral USLS from 2010-2012. Patients were identified on review of operative notes during the study time period. Patients were included in the study if they underwent the aforementioned surgery and had a preoperative standard protocol pelvic MRI at our institution within 1 year before their surgical date. Demographic, clinical, surgical, radiologic, and followup data were reviewed and collected as a secondary analysis (; ; personal communication of unpublished data). Patients were classified as surgical failure based on a composite score defined by the following information: presence of anatomic bulge beyond the hymen with sensation of vaginal bulge or the need for repeat treatment for prolapse via pessary or surgery by 1 year follow-up evaluation.

Imaging protocol Each pelvic MRI was performed on a standard 3-Tesla system (General Electric Company, GE Healthcare, Buckinghamshire, UK) with the use of an 8-channel torso phased-array coil with the patient in the supine position. Standard imaging for detailed anatomic evaluation of the pelvic floor muscles was performed with the use of T2-weighted fast-recovery-fast-spinecho sequence acquired in the axial, coronal, and sagittal planes. Before imaging, 60 mL of contrast gel was placed in the rectum for visualization of the colon. Static standard protocol pelvic MRI measurements at rest were collected from the departmental radiology report from the University of South Florida. The measurements included the pubococcygeal line (PCL), H-line, and M-line measured at rest from 2-dimensional midsagittal pelvic static images as read by a board-certified radiologist. The measurements were collected per previously defined guidelines by Law and Fielding.20 The PCL was determined as a linear measurement from the inferior border of the pubic bone to the last visible horizontal sacrococcygeal joint. The H-line was defined as the distance from inferior symphysis pubis to the

167 posterior anorectal junction that is 168 indicative of the anterioposterior length 169 of the levator hiatus; the M-line was 170 drawn perpendicularly from the PCL to 171 the most distal aspect of the H-line, 172 which is indicative of the descent of the 173 levator hiatus from the PCL. 174 The width of the levator ani 175 hiatus (WLH) was measured from 176 2-dimensional axial pelvic static images 177 at rest as previously described in publi178 cation.19 The WLH is defined as the 179 widest measurement between the inner 180 boundaries of the levator ani muscles 181 perpendicular to the midline axis of the Q5 182 image and measured immediately infe183 rior to the symphysis pubis as demon184 strated in Figure 1. All measurements ½F1 185 that were collected for H-line, M-line, 186 and WLH were collected and recorded in 187 millimeter dimensions. The estimated 188 LASV was then calculated for each 189 patient based on previously published 190 mathematical equation: eLASV ¼ 191 e72.838 þ 0.598 H-line þ 1.217 192 M-line þ 1.136 WLH.19 193 194 Statistical analysis 195 Statistical analysis was performed with 196 Stata software (version 13.1, Stata Sta197 tistical Software: Release 13; StataCorp 198 LP, College Station, TX). An optimal 199 cutoff point was calculated with the use 200 of Liu’s method by maximizing sensi201 tivity and specificity through the usage of 202 the cutoff finder.21,22 The optimal cutoff 203 point was then compared against cate204 goric values of surgical success/failure via 205 a contingency table. Fisher exact test was 206 performed to correlate eLASV to surgical 207 success/failure. A probability value of 208 <.05 was considered statistically signifi209 cant. An area under a receiver operating 210 characteristics curve was calculated to 211 detect prediction assessment. A logistic 212 regression analysis was then performed 213 to evaluate for confounders. 214 215 Results 216 Ninety-three women underwent lapa217 roscopic USLS during the study period. 218 Of these, 66 patients met the criteria and 219 were included in the study. Mean age was 220 58.6  12.7 years; mean body mass index 221 (BMI) was 27.7  5.5 kg/m2; median 222 parity was 2 (range, 1e6), and median

1.e2 American Journal of Obstetrics & Gynecology MONTH 2015 FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

ajog.org 223 224 225½T1 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256½F2 257 258 259 260 261 262 263 264 265 266 267 268½F3 269 270 271 272 273 274 275 276 277 278

UROLOGY

POP quantification system stage was 3 (range, 1e4; Table 1). Of the 66 patients who met inclusion criteria, 49 patients (74%) were diagnosed with stage III prolapse; 13 patients (20%) were diagnosed with stage II prolapse; 3 patients (4.5%) were diagnosed with stage IV prolapse, and 1 patient was diagnosed with stage I prolapse before surgery. Approximately one-half of the patients had anterior compartment predominate prolapse 37 (56%); 18 patients (27%) had apical predominate prolapse, and 11 patients (17%) had posterior compartment predominate prolapse. Most of the patients underwent a concomitant surgery; 57 patients (86%) underwent a total laparoscopic hysterectomy; 27 patients (41%) underwent a sling procedure; 17 patients (26%) underwent a posterior repair, and 2 patients underwent an anterior repair at the time surgery. The eLASV was calculated for all 66 patients from standard protocol preoperative MRIs. Thirteen patients (19.6%) met the criteria for surgical failure at or before 1 year. Calculated eLASV vs surgical success/failure for each patient was plotted on a scatter plot, and a formal optimal cutoff point of 38.5 was then calculated to optimize sensitivity and specificity (Figure 2). Among the patients with defined surgical failure, 84.6% (11/13) had a preoperative eLASV above the cutoff point of 38.5. Among the patients with defined surgical success, 39.6% (21/53) had a preoperative eLASV above the cutoff point (84.6% vs 39.6%; P ¼.0048) with a significant OR of 8.38 (95% confidence interval [CI], 1.69e41.68; P ¼ .009). Receiver operating characteristics curve presented in Figure 3 shows an area under the curve of 0.725 (95% CI, 0.603e0.847) with sensitivity of 84.6% (95% CI, 54.6%e98.1%) and specificity of 60.4% (95% CI, 46%e73.5%) at the defined optimal cutoff point of 38.5. Logistic regression analysis demonstrated no significant confounders among age (OR, 1.01 [95% CI, 0.94e1.08]), BMI (OR, 1.07 [95% CI, 0.95e1.21]), stage (OR, 2.91

Original Research

279 280 281 Static 2-dimensional 3-mm axial image of a female pelvis 282 283 284 A B 285 286 287 288 289 290 291 292 293 294 A, Static 2-dimensional 3-mm axial image of a female pelvis. B, The measurement of width of the 295 levator ani hiatus as the widest linear measurement between the inner boundaries of the levator ani 296 muscles perpendicular to the midline axis and measured immediately inferior to the symphysis pubis. 297 Wyman et al. ELASV predicting surgical failure. Am J Obstet Gynecol 2016. 298 299 300 [95% CI, 0.60e14.2]), or parity visits with no subjective or objective 301 (OR, 1.68 [95% CI, 0.98e2.88]; Table 2). signs of bulge recurrence. They were ½T2 302 Twelve patients of the total of 66 pa- instructed to follow up for a 12-month 303 tients attended 6- to 8-month follow-up postoperative visit and did not return 304 305 306 307 TABLE 1 308 Summary statistics 309 310 Total Success Patient characteristics (n ¼ 66) (n ¼ 53) Failure (13) P value Q11 311 312 Mean age, y  standard deviation 58.6  12.7 57.5  13.1 63  10.1 .17 Q12 313 Median pelvic organ prolapse 3 (1-4) 3 (1-4) 3 (1-4) .16 314 quantification system, stage (range) 315 Median parity, n (range) 2 (1-6) 2 (1-6) 3 (1-6) .09 316 27.7  5.5 27.5  5.7 28.7  4.4 .49 Body mass index, kg/m2 317 318 Previous gynecologic surgery, n (%) .68 319 No 55 (83.3) 45 (84.9) 10 (76.9) 320 Yes 11 (16.7) 8 (15.1) 3 (23.1) 321 Smoking history, n (%) .49 322 323 No 48 (72.7) 37 (69.8) 11 (84.6) 324 Yes 18 (27.3) 16 (30.2) 2 (15.4) 325 Diabetes mellitus, n (%) .25 Q13 326 No 61 (92.4) 50 (94.3) 11 (84.6) 327 328 Yes 5 (7.6) 3 (5.7) 2 (15.4) 329 Chronic obstructive pulmonary .10 Q14 330 disease, n (%) 331 No 54 (81.8) 41 (77.4) 13 (100) 332 Yes 12 (18.2) 12 (22.6) 0 333 Wyman et al. ELASV predicting surgical failure. Am J Obstet Gynecol 2016. 334 FIGURE 1

MONTH 2015 American Journal of Obstetrics & Gynecology FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

1.e3

Original Research

to clinic. All 12 patients were classified as surgical success secondary to last known visit documentation. The calculated eLASV for the 12 patients demonstrated a wide distribution (range, 10.22e67.59) similar to the whole sample distribution with 8 patients under the optimal cutoff point of 38.5 and 4 patients above the cut off value.

FIGURE 2

Liu’s method

Comments

The dark solid line represents odds ratio for each estimated levator ani subtended volume value; the dotted lines represent the upper and lower limits of 95% confidence interval. The optimal cutoff point of 38.5 was calculated based on optimization of the sensitivity and specificity. Patients with defined surgical failures 11 of 13 (84.6%) had an estimated levator ani subtended volume above the cutoff point of 38.5. Patients with defined surgical success 21 of 53 (39.6%) had an estimated levator ani subtended volume above the cutoff point (84.6% vs 39.6%; P ¼ .0048). CI, confidence interval; eLASV, estimated levator ani subtended volume; OR, odds ratio. Wyman et al. ELASV predicting surgical failure. Am J Obstet Gynecol 2016.

FIGURE 3

Area under a receiver operating characteristics curve web 4C=FPO

335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390

ajog.org

UROLOGY

Area under a receiver operating characteristics at the optimal cutoff point of 38.5. Wyman et al. ELASV predicting surgical failure. Am J Obstet Gynecol 2016.

Our data demonstrates patients with an eLASV of >38.5 on a preoperative standard pelvic MRI were associated with an increased risk of surgical failure for laparoscopic bilateral USLS by 1 year, regardless of age, BMI, stage, or parity. To date, vast amounts of research in MRI and ultrasonography of the female pelvis have increased our knowledge on pelvic floor dysfunction and have aided in the identification of risk factors for the development of pelvic floor disorders.5-9,11 However, the complete disease mechanism and pathogenesis are complex, multifactorial, and still not fully understood. Women with several risk factors may demonstrate normal pelvic organ support, whereas others with few or no risks factors experience prolapse.23 Furthermore, there is limited literature that identifies a woman at increased risk for recurrence of prolapse after surgical procedures. Levator ani avulsion, as detected by pelvic ultrasonography, has been identified to be a strong predictor for recurrence of anterior compartment prolapse after an anterior colporrhaphy.13,14 However, further studies are warranted to investigate prolapse recurrence after more surgical procedures with measurements of levator ani integrity as a predictor for surgical outcomes. The novelty of eLASV as an indirect measurement of the laxity of the levator ani muscle as a whole complex separates it methodologically from diagnosing levator ani avulsion. Identification of women at an increased risk for surgical failure or recurrence of POP after advanced surgical procedures would be invaluable in a surgical subspecialty that has a reoperation rate as high as 30% after a primary surgery.24 This study represents a step in

1.e4 American Journal of Obstetrics & Gynecology MONTH 2015 FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446

ajog.org 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502

UROLOGY

the direction of the identification of patients at increased risk for surgical failure and the potential of stratification of future patients into specific surgical procedures based on the likelihood of success after an advanced pelvic reconstructive procedure. Abdominally placed mesh, either robotically, laparoscopically, or open procedure, for a sacral colpopexy is considered the gold standard for apical suspension in patients with POP.25 However, there is an increased concern for the use of synthetic mesh in reconstructive pelvic surgery.26 USLS is a native tissue procedure to address apical support and has been shown to have similar apical success rates as sacral colpopexy.27 As Dietz9 stated, patient selection thus far has played a very small role in the discussion regarding the use of mesh vs native tissue in reconstructive surgery. Patient selection and stratification into certain reconstructive procedures will likely change once clinicians learn to diagnose levator ani trauma and identify patients at high risk of prolapse recurrence after reconstructive surgery.9 We demonstrate an objective measure of levator ani muscle laxity calculated from standard 2-dimensional dynamic pelvic MRI measurements (H-line and M-line) that were obtained directly from radiology reports along with one 2dimensional linear measurement that is obtained easily from radiographic images. The method is simple and relevant to a daily clinical and surgical practice and can be performed easily by any clinician and requires little to no formal training. Furthermore, eLASV measurements have the potential to be a prognostic tool to aid in future counseling of patients on surgical options for treatment of POP. The strengths of this study include the simple and straightforward method to calculate eLASV as an applicable measurement of levator ani integrity from standard protocol 2-dimensional dynamic pelvic MRIs that can be used as a predictive model for the identification of patients at risk for surgical failure in a busy surgical practice. Our findings, if validated, will help clinicians and patients to make a more informed

decision about surgical management for apical prolapse. The limitations of the study include the retrospective nature of the study and all inherent limitations that are involved in retrospective cohorts, including patients lost to follow up evaluation. Patients who were included in this retrospective study were counseled on all treatment options for symptomatic POP, including expectant management, pessary, and surgical interventions. For a patient with apical predominate prolapse, we offer laparoscopic, robotic, or open repair with native tissue or mesh augmentation. The patient ultimately determines her surgical approach and procedure. Our technique for laparoscopic USLS includes a bilateral approach with either delayed absorbable or permanent suture (polydioxanone or nylon), which is a surgeon preference. Most patients did receive a concomitant hysterectomy at the time of the procedure. All of the MRIs that were reviewed for this retrospective study were performed for clinical indications and at the surgeon’s discretion. Patients with defecatory dysfunction, concern for rectal prolapse, referrals from our colleagues within colorectal surgery department, or patients who had an unclear physical examination in office with multicompartmental prolapse were considered for further clinical evaluation by a pelvic MRI before proceeding with surgery. In conclusion, patients with a calculated eLASV of >38.5 on a preoperative pelvic MRI were associated with an increased risk for surgical failure for laparoscopic USLS, with a significant OR of 8.38 (95% CI, 1.69e41.68; P ¼ .009). This increased risk for surgical failure was seen, regardless of age, BMI, stage, or parity. Estimated LASV may be used as a prognostic test for surgical outcomes and may aid when counseling patients for apical suspension. Finally, predictive models such as ours should undergo a repeatability and reliability analysis along with external validation. We already have performed a repeatability, interobserver reliability, and interobserver agreement analysis

Original Research

TABLE 2

Logistics regression analysis

Variable

Odd ratio (95% confidence interval)

Age

1.01 (0.94e1.08) .95

P value

Body mass 1.07 (0.95e1.21) .27 index Stage

2.91 (0.60e14.2) .19

Parity

1.68 (0.98e2.88) .06

Wyman et al. ELASV predicting surgical failure. Am J Obstet Gynecol 2016.

within our research group that will be published as a separate and complementary article to this study. However, an external validity analysis and a prospective cohort study are warranted to confirm eLASV as a future predictor for surgical outcomes in female pelvic medicine and reconstructive surgery. n

Uncited Reference 28. Q6

References 1. Boyles SH, Weber AM, Meyn L. Procedures for pelvic organ prolapse in the United States 1979-1997. Am J Obstet Gynecol 2003;188: 108-15. 2. Luber KM, Boero S, Choe JY. The demographics of pelvic floor disorders: current observations and future projections. Am J Obstet Gynecol 2001;184:1496-503. 3. Denman MA, Gregory WT, Boyles SH, Smith V, Edwards SR, Clark AL. Reoperation 10 years after surgically managed pelvic organ prolapse and urinary incontinence. Am J Obstet Gynecol 2008;198:551-5. 4. Hendrix SL, Clark A, Nygaard I, Aragaski A, Barnabe V, McTiernan A. Pelvic organ prolapse in the women’s health initiative: gravity and gravidity. Am J Obstet Gynecol 2002;186: 1160-6. 5. Shek Kl, Dietz HP. The effect of childbirth on hiatal dimensions. Obstet Gynecol 2009;113: 1272-8. 6. DeLancey JO, Kearney R, Chou Q, Speights S, Binno. The appearance of levator ani muscle abnormalities in magnetic resonance images after vaginal delivery. Obstet Gynecol 2003;101:46-53. 7. Dietz HP, Simpson JM. Levator trauma is associated with pelvic organ prolapse. BJOG 2008;115:979-84. 8. Dietz HP, Lanzarone V. Levator trauma after vaginal delivery. Obstet Gynecol 2005;106: 707-12.

MONTH 2015 American Journal of Obstetrics & Gynecology FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

1.e5

503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558

Original Research 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614

ajog.org

UROLOGY

9. Dietz HP. Pelvic Floor trauma in childbirth. Aust N Z J Obset Gynecol 2013;53:220-30. 10. Dietz H, De Leon J, Shek K. Ballooning of the levator hiatus. Ultrasound Obstet Gynecol 2008;31:676-80. 11. DeLancey JO, Morgan DM, Fenner DE, et al. Comparison of levator ani muscle defects and function in women with and without pelvic organ prolapse. Obstet Gynecol 2007;109: 295-302. 12. Dietz HP, Steensma AB. The prevalence of major abnormalities of the levator ani in urogynaecological patients. BJOG 2006;113: 225-30. 13. Dietz HP, Charntarason V, Shek KL. Levator avulsion is a risk factor for cystocele recurrence. Ultrasound Obstet Gynecol 2010;36:76-80. 14. Wong V, Shek KL, Rane A, Goh J, Krause H, Dietz HP. Is levator avulsion a predictor of cystocele recurrence following anterior vaginal mesh replacement? Ultrasound Obstet Gynecol Q7 2013;42:230-4. 15. Singh K, Jakab M, Reid WMN, Berger LA, Hoyte L. Three-dimensional MRI assessment of levator ani morphology in different grades of prolapse. Am J Obstet Gynecol 2003;188: 910-5. 16. DeLancy JO. Anatomy and biomechanics of genital prolapse. Clin Obstet Gynecol 1993;36: 897-909. 17. Norton P. Pelvic floor disorders: the role of fascia and ligaments. Clin Obstet Gynecol 1993;36:926-38.

18. Rodrigues AA, Herrera-Hernadez MC, Bassalydo R, et al. Levator ani subtended volume: a novel parameter to evaluate levator ani muscle laxity in pelvic organ prolapse. Am J Obstet Gynecol 2012;206:244.e1-9. 19. Rodrigues AA Jr, Herrera-Hernadez MC, Bassalydo R, et al. Estimates of the levator ani subtended volume based on magnetic resonance linear measurements. Neurourol Urodyn 2014. Epub ahead of print. 20. Law YM, Fielding JR. MRI of pelvic floor dysfunction: review. AJR Am J Roentgenol 2008;191:S45-53. 21. Budczies J, Klauschen F, Sinn BV, et al. (2012) Cutoff finder: a comprehensive and straightforward web application enabling rapid biomarker cutoff optimization. PLoS One 2012;7(12):e51862. 22. Liu DC, Nocedal J. On the limited memory BFGS method for large scale optimization. Mathematical Programming 45 1989;503-528. 23. Lammers K, Prokop M, Vierhout M, Kluivers K, Futterer JJ. A pictorial overview of pubovisceral muscle avulsions on pelvic floor magnetic resonance imaging. Insights Imaging 2013;4:431-41. 24. Olsen AL, Smith VJ, Bergstrom JO, Colling JC, Clark AL. Epidemiology of surgically managed pelvic organ prolapse and urinary incontinence. Obstet Gynecol 1997;89: 501. 25. Maher C, Feiner B, Baessler K, Glazener CMA. Surgical management of pelvic

organ prolapse in women. Cochrane Database Syst Rev 2010;4:CD004014. 26. Nygaard I, Brubaker L, Zyczynski HM, et al. Long-term outcomes following abdominal sacrocolpopexy for pelvic organ prolapse. JAMA 2013;309:2016-24. 27. Filmar GA, Fisher HW, Aranda E, Lotze PM. Laparoscopic uterosacral ligament suspension and sacral colpopexy: results and complicaQ8 tions. Int Urogynecol J 2014;25:1645-53. 28. Barber MD, Brubaker L, Nygaard I, et al. Defining success after surgery for pelvic organ Q10 prolapse. Obstet Gynecol 2009;114:600-9.

Author and article information From the Department of Obstetrics and Gynecology, Division of Female Pelvic Medicine and Reconstructive Surgery, University of South Florida, Tampa, FL (Drs Wyman, Hahn, Bassaly, Hart, Miladinovic, and Hoyte); the Department of Surgery, University of Sa˜o Paulo, Sao Q9 Paulo, Brazil (Dr Rodrigues); and the Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, Emory University, Atlanta, GA (Dr Greene). Received Aug. 17, 2015; revised Oct. 30, 2015; accepted Nov. 9, 2015. The authors report no conflict of interest. Presented as an oral presentation at the AUGS 36th Annual Scientific Meeting/PFD Week, Seattle, WA, October 13-17, 2015. Corresponding author: Allison M. Wyman, MD. [email protected]

1.e6 American Journal of Obstetrics & Gynecology MONTH 2015 FLA 5.4.0 DTD  YMOB10773_proof  13 December 2015  12:57 pm  ce

615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670