A Feasibility Study to Determine Whether Clinical Contrast Enhanced Magnetic Resonance Imaging can Detect Increased Bladder Permeability in Patients with Interstitial Cystitis

PURPOSE

Interstitial cystitis/bladder pain syndrome is a bladder pain disorder associated with voiding symptomatology and other systemic chronic pain disorders. Currently diagnosing interstitial cystitis/bladder pain syndrome is complicated as patients present with a wide range of symptoms, physical examination findings and clinical test responses. One hypothesis is that interstitial cystitis symptoms arise from increased bladder permeability to urine solutes. This study establishes the feasibility of using contrast enhanced magnetic resonance imaging to quantify bladder permeability in patients with interstitial cystitis.

MATERIALS AND METHODS

Permeability alterations in bladder urothelium were assessed by intravesical administration of the magnetic resonance imaging contrast agent Gd-DTPA (Gd-diethylenetriaminepentaacetic acid) in a small cohort of patients. Magnetic resonance imaging signal intensity in patient and control bladders was compared regionally and for entire bladders.

RESULTS

Quantitative assessment of magnetic resonance imaging signal intensity indicated a significant increase in signal intensity in anterior bladder regions compared to posterior regions in patients with interstitial cystitis (p <0.01) and significant increases in signal intensity in anterior bladder regions (p <0.001). Kurtosis (shape of probability distribution) and skewness (measure of probability distribution asymmetry) were associated with contrast enhancement in total bladders in patients with interstitial cystitis vs controls (p <0.05). Regarding symptomatology interstitial cystitis cases differed significantly from controls on the SF-36®, PUF (Pelvic Pain and Urgency/Frequency) and ICPI (Interstitial Cystitis Problem Index) questionnaires with no overlap in the score range in each group. ICSI (Interstitial Cystitis Symptom Index) differed significantly but with a slight overlap in the range of scores.

CONCLUSIONS

Data suggest that contrast enhanced magnetic resonance imaging provides an objective, quantifiable measurement of bladder permeability that could be used to stratify bladder pain patients and monitor therapy.

How does 3D endovaginal ultrasound compare to magnetic resonance imaging in the evaluation of levator ani anatomy?

INTRODUCTION AND HYPOTHESIS

To compare magnetic resonance imaging (MRI) to 3D endovaginal ultrasound (EVUS) in the evaluation of major levator ani defects in women with pelvic floor disorders.

METHODS

A total of 21 subjects with pelvic floor with complaints of pelvic floor disorders were included in this study. EVUS imaging of the levator ani muscle (LAM) was performed in all subjects, and the LA muscle groups of interest evaluated were the puboanalis (PA), puborectalis (PR), and pubovisceralis (PV) muscles. The right and left subdivisions were evaluated separately, and classified as (i) normal, normal with only minor irregularities, grossly abnormal, or absent, or (ii) by the levator ani deficiency (LAD) score and classified by no defect (complete attachment of muscle to the pubic bone), <50% detachment or loss, >50% detachment or loss, and completely detached or complete muscle loss. Paired data were analyzed with McNemar's test or Bowker's test of symmetry.

RESULTS

When unilateral LAM subdivisions were classified as "normal," "normal with minor irregularity," "grossly abnormal," and "absent," there were no significant differences between MRI and EVUS by categorization of LAM defects. Comparing "normal" versus "abnormal," there was no difference between imaging modalities. When compared by LAD score evaluation, there were no differences in the categorization of unilateral defects between MRI and EVUS.

CONCLUSIONS

Endovaginal 3D US is comparable to MRI in its ability to identify both normal and abnormal LAM anatomy. Neurourol. Urodynam. 36:409-413, 2017. © 2015 Wiley Periodicals, Inc.

Surgical Care Processing in Major Oklholma City Hosptal: The Surgeons' Perspective

PURPOSE

This study aimed to assess processing of surgical care provided at major Oklahoma City hospitals based on surgeons'perception.

METHODS

A questionnaire was sent out to Oklahoma County Medical Society surgeons using survey monkey to assess surgeons' perception of surgical care provided by major hospitals in Oklahoma City metropolitan area. The email contained a short introduction of study and the general aim of the study. Student t test was applied to compare groups mean. P value <0.05 was considered significant.

RESULTS

79 valid responses were identified. 25% of surgeons scored that their patients waited in the post-op recovery area between 31-60 minutes before they were roomed, with a 90% surgeon satisfaction rate. Compared to the longer waiting times this satisfaction rate was significantly higher (P < 0.0001). 64.6% of surgeons reported 31-60 minutes turn-over time between cases with only an 8% satisfaction rate. 10-30 minutes turnover time was reported in 13.9% of participants with 72.7% satisfaction rate which was significant when compared to the former group. The surgeons scored that their patients presented to the hospital 1-2 hours before surgery 55.7% of the times and 92.7% of the surgeons were satisfied with this process (P < 0.0001).

CONCLUSION

Surgeons'satisfaction increases with decreased patients processing times.

Levator Plate Upward Lift on Dynamic Sonography and Levator Muscle Strength

OBJECTIVES

To compare digital palpation with levator plate lift measured by endovaginal and transperineal dynamic sonography.

METHODS

Dynamic transperineal and endovaginal sonographic examinations were performed as part of multicompartmental pelvic floor functional assessment. Patients were instructed to perform Kegel contractions while a probe captured a video clip of levator plate movement at rest and during contraction in a 2-dimensional midsagittal posterior view. We measured the distance between the levator plate and the probe on endovaginal sonography as well as the distance between the levator plate and the gothic arch of the pubis on transperineal sonography. The change in diameter (lift) and levator plate lift ratio (lift/rest × 100) were calculated. Pelvic floor muscle strength was assessed by digital palpation and divided into functional and nonfunctional groups according to the Modified Oxford Scale. Mean differences in levator plate upward lift were compared by Modified Oxford Scale scores using Student t tests and analysis of variance.

RESULTS

Seventy-four women were available for analysis. The mean age was 55 (SD, 11.9) years. When measured by vaginal dynamic sonography, mean lift and lift/rest ratio values increased with increasing Modified Oxford Scale score (analysis of variance, P= .09 and .04, respectively). When scores were categorized to represent nonfunctional (0-1) and functional (2-5) muscle strength groups, the mean lift (3.2 versus 4.6 mm; P = .03) and lift/rest ratio (13% versus 20%; P = .01) values were significantly higher in women with functional muscle strength. All patients with lift of 30% or greater detected by vaginal sonography had functional muscle strength.

CONCLUSIONS

A greater levator plate lift ratio detected by dynamic endovaginal sonography was associated with higher muscle strength as determined by the Modified Oxford Scale. This novel measurement can be incorporated into sonographic evaluation of levator ani function.

Is a new high-resolution probe better than the standard probe for 3D anal sphincter and levator ani imaging?

The aim of our study was to determine the accuracy of a new three-dimensional (3D) endoluminal ultrasound probe in assessing the levator ani muscle and anal sphincter complex. A total of 85 patients who had undergone concurrent 3D endovaginal (EVUS) and 3D endoanal (EAUS) ultrasound with both the standard BK 2052 probe and the new high-definition BK 8838 probes were included. For EVUS volumes, the levator ani deficiency (LAD) scores were calculated for each probe. For the EAUS volumes, any defects in the external anal sphincter (EAS) and the internal anal sphincter (IAS) visualized with each probe were recorded. The 3D volumes were evaluated in a blinded fashion. Appropriate statistics were utilized to assess absolute agreements between each pair of imaging modalities. The mean age of the patient population was 59 years (SD ± 10.76), the mean body mass index (BMI) was 28.36 (SD ± 5.99), and the median parity was 2 (range 1, 7). In all, 93% of the patients were Caucasian, 31% had stage 0 or 1 prolapse, while 59% had stage 2 prolapse. The mean total LAD score obtained on EVUS with the standard and the new probes were 11.49 (SD ± 4.94) and 11.53 (SD ± 5.01), respectively, p = 0.3778. Among the 53 patients who had EAUS with both probes, exact agreement for visualization of EAS and IAS for the standard and the new probes was 83% and 98%, respectively. Both transducers can be used for endovaginal imaging of the levator ani muscles interchangeably. Both transducers can be used for endoanal imaging of anal sphincter complex interchangeably.

How well can levator ani muscle morphology on 3D pelvic floor ultrasound predict the levator ani muscle function?

INTRODUCTION AND HYPOTHESIS

The aim of our study was to assess the performance of levator ani muscle deficiency (LAD) evaluated by 3D endovaginal ultrasound (EVUS) to detect pelvic floor muscle function as assessed by digital examination.

METHODS

This cross-sectional study was conducted among 77 patients referred to our urogynecology clinic for pelvic floor dysfunction symptoms. Patients underwent physical examinations including digital pelvic muscle strength assessment using the Modified Oxford scale (MOS). EVUS volumes were evaluated and levator ani muscles were scored according to a validated LAD scoring system. MOS scores were categorized as nonfunctional (scores 0-1) and functional (scores 2-5).

RESULTS

Mean age of participants was 56 (SD ± 12.5) and 71% were menopausal. Overall, 32.5% had nonfunctional muscle strength and 44.2% were classified as having significant LAD. LAD identified by ultrasound had a sensitivity of 60% (95% CI 41 -79%) for detecting nonfunctional muscle and a specificity of 63% (95% CI 50 -77%) for detecting functional muscle. Overall, LAD demonstrated fair ability to discriminate between patients with and those without poor muscle function (area under the ROC curve = 0.70 [95% CI 0.58-0.83]). Among patients with an LAD score of 16-18, representing almost total muscle avulsion, 70% had nonfunctional MOS scores, whereas in patients with normal/minimal LAD (scores of 0-4), 89.5% had functional MOS scores.

CONCLUSIONS

Levator ani deficiency and MOS scales were moderately negatively correlated. Among patients with normal morphology or the most severe muscle deficiency, LAD scores can identify the majority of patients with functional or nonfunctional MOS scores respectively.

Clinical and ultrasonographic study of patients presenting with transvaginal mesh complications

AIM

The objective of this study was to investigate the clinical and ultrasonographic findings of women who had three-dimensional endovaginal ultrasound (EVUS) for the management of vaginal mesh complications.

METHODS

This was a retrospective study of patients that had EVUS due to mesh complications at a tertiary care center. The clinical charts were reviewed. The stored 3D volumes were reviewed regarding mesh information by two examiners independently. The predictive value of physical examination for detection of vaginal mesh was calculated. Patient outcomes were reviewed.

RESULTS

Seventy-nine patients presented to our center because of their, or their physicians' concern regarding mesh complications. Forty-one (51.9%) had vaginal/pelvic pain, and 51/62 (82.2%) of sexually active women experienced dyspareunia. According to ultrasonographic findings, mesh or sling was not demonstrated in six patients who believed they have had mesh/sling implantation. The positive predictive value for vaginal examination was 94.5% (95% CI: 84.9%-98.8%), negative predictive value was 12.5% (95% CI: 2.8%-32.4%), sensitivity was 72.2% (95% CI: 59.4%-81.2%), and specificity was 50.0% (95% CI: 12.4%-87.6%). Fifty-four patients were indicated for surgical treatment. Median postoperative review was 12 (range, 3-18) months and 38/53 (71.7%) patients were satisfied.

CONCLUSIONS

The most common complaints of vaginal mesh complications were pain and dyspareunia. EVUS appeared to be helpful for assessing mesh presence, location, and extent including planning for surgical intervention.

Is there a correlation between levator ani and urethral sphincter complex status on 3D ultrasonography?

INTRODUCTION AND HYPOTHESIS

To determine the correlation between levator ani deficiency (LAD) and urethral sphincter complex measurements as visualized on 3D endovaginal ultrasonography, and to compare the LAD score with continence status.

METHODS

This was a retrospective analysis of patients seen at our institution between January 2011 and August 2013. Patients were dichotomized into those with urodynamic stress urinary incontinence (SUI) and those with no SUI. Levator ani status was evaluated using a validated scoring system yielding scores of 0 - 6 (normal levator ani/mild LAD), 7 - 12 (moderate LAD), and 13 - 18 (severe LAD). The length, horizontal diameter, and cross-sectional area of the urethra, and the length, width, and the area of the rhabdomyosphincter and smooth muscle sphincter were likewise measured using 3D ultrasound volumes.

RESULTS

Of the 80 patients included, 54 (67.5%) had SUI and 26 (32.5%) were continent. 18 (22.5%) had evidence of mild LAD, 54 (67.5%) had moderate LAD, and 8 (10.0%) had severe LAD. Among patients with SUI, those with normal levator ani muscles or mild LAD had greater urethral smooth muscle width than those with moderate and severe LAD (p = 0.0238). A greater proportion of patients with SUI also had moderate to severe LAD than continent patients (p = 0.0177, OR 3.59, 95% CI 1.21 - 10.65). There was no difference in LAD distribution by type of stress incontinence (presence or absence of intrinsic sphincter deficiency; p =  .2377).

CONCLUSIONS

LAD and urethral sphincter complex status, as visualized on 3D ultrasonography, are independent factors. Moderate to severe LAD is more prevalent in patients with SUI.

Obstetric laceration repair in the United States: is there a common practice?

OBJECTIVE

To assess practice preferences in the repair of severe obstetric lacerations among obstetrician/gynecologists in the United States.

STUDY DESIGN

A survey detailing third and fourth degree laceration repair techniques was distributed to 634 obstetrician/gynecologists from demographically diverse areas of the United States. Categorical outcomes were compared among respondents using chi2 or Fisher's exact test where appropriate.

RESULTS

Of the 266 respondents, there were 124 self-reported "experts" (47%) and 106 physicians-in-training (40%). Repair techniques were compared between experts versus nonexperts and trainees versus practicing physicians. There were no significant differences found between either comparison group on the type and size of suture utilized or preferred method of closure for repair.

CONCLUSION

There is little variation in the practice pattern of complex laceration repairs among obstetrician-gynecologists in the United States. This commonality should encourage the design of standard teaching models and techniques for physicians in training.

Three-dimensional endovaginal sonography of synthetic implanted materials in the female pelvic floor

The objective of this pictorial essay is to emphasize the ability of 3-dimensional endovaginal sonography to image synthetic implanted materials in the female pelvic floor. Implanted materials discussed in this pictorial essay include polypropylene vaginal mesh, polypropylene suburethral slings, and urethral bulking agents. Three-dimensional endovaginal sonography allows for more detailed imaging compared to computed tomography and magnetic resonance imaging of the female pelvic floor, in that each plane can be manipulated to show unique images of synthetic implanted materials.

Intra- and interobserver reliability of levator ani muscle biometry and avulsion using three-dimensional endovaginal ultrasonography

OBJECTIVES

To test intra- and interobserver reliability of assessment of levator ani muscle (LAM) biometry and avulsion using antenatal and postnatal three-dimensional (3D) endovaginal ultrasonography (EVUS), and to determine levator-urethra gap (LUG) values on EVUS.

METHODS

Primigravid women were scanned prior to delivery, early postpartum and 3 months postpartum, with EVUS performed at rest using a standardized protocol. During post-processing, measurements were taken in the plane of minimal hiatal dimensions by two independent investigators blinded to the clinical information and each other's results. LAM attachment to the pubic bone was assessed at the pubococcygeus and puborectalis levels using a score system: (1) intact; (2) partial avulsion (< 50%); (3) partial avulsion (≥ 50%); and (4) complete avulsion. Intraclass correlation coefficients (ICCs) and limits of agreement (LOAs) were calculated for each time point, with intraobserver analysis conducted in a random sample of 20 women scanned 3 months following delivery.

RESULTS

One hundred and sixty-nine antenatal scans, 83 early postpartum scans and 75 scans at 3 months postpartum were performed. The intra- and interobserver ICCs, respectively, were 0.95 and 0.86-0.88 for hiatal area, 0.90 and 0.16-0.74 for hiatal transverse diameter, 0.91 and 0.73-0.80 for hiatal anteroposterior diameter, 0.50 and 0.32-0.52 for LAM thickness at the '9 o'clock position' and 0.55 and 0.33-0.45 for LAM thickness at the '3 o'clock position'. Both intra- and interobserver analysis revealed acceptable LOAs for hiatal measurements, but the LOAs were wide for thickness measurements. The correlation of LAM avulsion score was excellent on intra- and interobserver analysis. Antenatal mean ± SD LUGs were 18.8 ± 2.4 mm and 19.2 ± 2.3 mm on right and left sides, respectively; the intraobserver ICC was 0.82-0.91 but LOAs were wide, while interobserver ICC was 0.13-0.68 and also had wide LOAs.

CONCLUSIONS

3D-EVUS is a reliable tool for the assessment of hiatal measurements and LAM avulsion in women during pregnancy and after delivery, but performs less well for measurements of LAM thickness and LUG. EVUS can therefore be used in research studies involving childbirth and recurrent prolapse.

Levator hematoma at the attachment zone as an early marker for levator ani muscle avulsion

OBJECTIVES

Childbirth causes overstretching of the levator ani muscle (LAM), predisposing to avulsion. LAM avulsion has not been evaluated early postpartum using endovaginal ultrasound (EVUS). The aim of this study was to evaluate the relationship between hematomas and LAM avulsion using EVUS and palpation early and late postpartum.

METHODS

Nulliparous women were studied prospectively at 36 weeks' gestation and within 4 days and 3 months postpartum. Palpation and high-frequency three-dimensional EVUS were performed. Two independent investigators reviewed the scans.

RESULTS

No antenatal LAM avulsions were found (n = 269). 114/199 (57.3%) women seen early postpartum agreed to examination. 27/114 (23.7%) had well delineated, hypoechoic areas consistent with hematomas (100% agreement), 26 following vaginal delivery, one following emergency Cesarean section. In total, 38 hematomas were found (11 bilateral, 16 unilateral). Hematomas away from the attachment zone of the LAM to the pubic bone (n = 22) resolved. Hematomas at the attachment zone (n = 16) manifested as pubococcygeus avulsions 3 months postpartum. In addition to these 16 avulsions, we found another 20 at 3 months postpartum. 13/20 were not scanned early postpartum and in seven no hematomas were seen, but avulsion was seen early postpartum. Overall, LAM avulsion was found in 23/191 (12.0%) women (13 bilateral, 10 unilateral) 3 months postpartum. Hematomas were significantly associated with episiotomy, instrumental delivery and increased hiatal measurements. Palpation was unreliable early postpartum as only seven avulsions were diagnosed.

CONCLUSION

Hematomas at the site of LAM attachment to the pubic bone always result in avulsion diagnosed 3 months postpartum. However, one third of avulsions are not preceded by a hematoma at the site of LAM attachment to the pubic bone.

Imaging of Urethral Bulking Agents

Urethral bulking is an office procedure for treatment of stress urinary incontinence that has increased in popularity in recent years. Numerous types of urethral bulking agents have been used since its introduction in the 1930s. Typically, these agents are imaged using specialty 3D 360° field-of-view transducers; however, a sonographer, during a pelvic or renal examination, may inadvertently find and image an echogenic structure near the urethrovesical junction in patients with a history of urethral bulking. Familiarizing oneself with the sonographic appearance of urethral bulking agents and optimizing techniques to obtain improved images of these agents may eliminate the need for additional imaging for the patient. Urethral bulking can be readily imaged with transducers commonly found in most ultrasound departments. This review will focus on the sonographic characteristics of urethral bulking agents and knowing when and how to use appropriate transducers to image the urethra.

Evaluation of vaginal cysts and masses by 3-dimensional endovaginal and endoanal sonography

The purpose of this pictorial essay is to describe the utility of 3-dimensional endovaginal and endoanal sonography in the assessment of vulvovaginal cysts and masses. It is accepted that compared with transabdominal pelvic sonography, transvaginal end-fire sonography provides improved resolution for visualization of female reproductive organs with fewer artifacts. To visualize the structures that are located in or lateral to the vaginal canal, side-fire 3-dimensional endovaginal or endoanal sonography can be used. This special technique has the advantage of maintaining the spatial anatomic relationship of any abnormality in the vagina.

Development of an in-house endoanal ultrasound teaching phantom

OBJECTIVES

The aim of this study was to construct an anatomically correct phantom for visualization of anal sphincter complex structures.

METHODS

To ake an endoanal ultrasound phantom, we experimented with a variety of commercially available materials to simulate hyperechoic, hypoechoic, and isoechoic tissue consistency. We created external anal sphincter muscle and the levator plate using stand-alone density gel and microbubbles to simulate the echogenicity of the muscles. A mold was created in a container, the muscles were inserted, and the mold was filled with high-density clear gel and allowed to fill. Once finished, the container was sealed tightly and stored for later use. To evaluate the accuracy of the model, 6 ultrasound imaging raters from different disciplines were included. The raters were administered a 6-item Internet-based interactive test using 2-dimensional images obtained from scanning the phantom. Rater agreement was determined. The Fleiss κstatistic was calculated to determine inter-rater reliability.

RESULTS

The raters identified the structures in 32 (89%) of 36 test questions. There was good to excellent agreement among the readers. Agreement rates for visualization of the external anal sphincter, perineal body, and internal anal sphincter were 67%, 83%, and 100%, respectively.

CONCLUSIONS

An endoanal phantom can be constructed as a simulator for endoanal sonography.

Does age affect visualization of the levator ani in nulliparous women?

INTRODUCTION AND HYPOTHESIS

Our aim was to assess whether differences in the ages of nulliparous women affect: (1) interobserver reliability, and (2) visualization of the levator ani (LA) muscle subdivisions in nulliparous women using 3D endovaginal ultrasound (3D-EVUS).

METHODS

This was a cross-sectional study. Community-dwelling nulliparous women ages 21-70 years were recruited. Participants underwent a standard examination and a 3D-EVUS. LA subdivisions of interest included the puboperinealis, puboanalis, pubococcygeus, puborectalis, and ileococcygeus muscles. Each ultrasound (US) volume was scored using a validated scale and assessed by two observers. Defect severity was scored for each muscle from 0 (no defect) to 6 (complete muscle loss). A summed score of the two sides was grouped as normal (0), minor (1-3), or major (4-6). Bias was examined using Bland-Altman plots. Intraclass coefficients were calculated to report agreement of total scores. Spearman's rank correlation was used to evaluate the association between age and LA scores.

RESULTS

Eighty nulliparous women were evaluated. Exact agreement for bilateral scoring of each LA subdivision ranged from 82 % to 84 %. Bilateral scoring of the puboperinealis, puborectalis, and ileococcygeus showed moderate to substantial agreement. Bilateral scores of the puboperinealis demonstrated substantial agreement between observers, with an ICC of 0.8 and a mean difference of -0.2 using the Bland-Altman analysis. When women were analyzed by age decade, reader agreement was overall good to excellent. There was no significant correlation between increasing age and total LA muscle scores (r = 0.179, p = 0.113).

CONCLUSIONS

Interobserver reliability or visualization of the LA muscle in nulliparous women was not affected by a woman's age.

The determinants of minimal levator hiatus and their relationship to the puborectalis muscle and the levator plate

OBJECTIVE

To determine the muscles comprising the minimal levator hiatus.

DESIGN

Cross-sectional study.

SETTING

The University of Oklahoma Health Sciences Center, USA.

POPULATION

Eight female fresh frozen pelves and 80 nulliparouswomen.

METHODS

Three-dimensional endovaginal ultrasound was performed in eight fresh frozen female pelves. The structures of the levator hiatus were tagged with needles and the cadavers were dissected to identify the tagged structures. A group of 80 nullipara underwent 3D endovaginal ultrasound, and the minimal levator hiatus area, puborectalis area, and anorectal angle were assessed, and normal values were obtained.

MAIN OUTCOME MEASURES

Anatomic borders of minimal levator hiatus and normality in pelvic floor measurements.

RESULTS

The pubococcygeus forms the inner lateral border and anterior attachment of the minimal levator hiatus to the pubic bone. The puboanalis fibres are immediately lateral to pubococcygeus attachments. There are variable contributions of the puborectalis fibres lateral to the puboanalis attachment. The posterior border of the minimal levator hiatus is formed by the levator plate. Eighty community-dwelling nulliparous women underwent 3D endovaginal ultrasound. The median age was 47 years (range 22-70 years). The mean of minimal levator hiatus and puborectalis hiatus areas were 13.4 cm(2) (±1.89 cm(2) SD) and 14.8 cm(2) (±2.16 cm(2) SD). The mean anorectal and levator plate descent angles were 156° (±10.04° SD) and 15.9° (±8.28° SD).

CONCLUSION

Anterior and lateral borders of the minimal levator hiatus are formed mostly by pubococcygeus. The puborectalis, pubococcygeus, and iliococcygeus form the bulk of the levator plate.

Medical student knowledge of global health problems: obstetric fistulas in developing countries

OBJECTIVE

To evaluate medical students in the United States at several medical schools regarding their knowledge of the global health burden of obstetric fistulas.

STUDY DESIGN

A cross-sectional survey was conducted in 8 schools across the United States over a period of 6 months. The survey was composed of 18 questions on epidemiology, pathology, and treatment of fistulas. It was a web-based module accessed through an emailed link. It was sent to 5,103 medical students' email addresses at the 8 institutions once a week for 4 weeks. SPSS paired student t tests was used for statistical analysis.

RESULTS

Of the 1,089 students from 8 medical schools that initially began the survey, 965 completed this voluntary and anonymous survey, with a 21% response rate and 19% completion rate. Overall the students averaged 11/18 (60.7%) correct on this survey. The knowledge of obstetric fistula improved, but not significantly, with increasing level of medical school education, with first-year medical students achieving 10/18 (55%) correct and senior medical students achieving 12/18 (67%) correct (p = 0.1).

CONCLUSION

U.S. medical students' knowledge of obstetric fistulas in developing countries does not increase significantly over 4 years of medical school education. While this condition presents largely in the developing world, given rapid globalization as well as increased international health experiences for U.S.-trained health professionals,further effort should be placed in improving medical student knowledge of this devastating condition.