Vaginal axis on MRI after unilateral and bilateral sacral hysteropexy: a controlled study

The feasibility of uterine-vaginal axis MRI-based as evaluation of surgical efficacy in women with pelvic organ prolapse

Background

The aim of this study was to provide a potential surgical efficacy assessment in the treatment of pelvic organ prolapse (POP).

Methods

A retrospective cohort study was performed on magnetic resonance imaging (MRI) imaging data of 16 non-prolapsed (control group) and 30 preoperative and postoperative POP (case group) women from 2019 to 2021 at the First Affiliated Hospital of Kunming Medical University. MRI diagnoses and measures of the relevant anatomical points at rest were used to analyze the healthy control data and the data from POP women before and after surgery.

Results

The middle vaginal-PICS line angle (78.12°±15.03° vs. 69.35°±11.51°, 78.12°±15.03° vs. 61.56°±9.58°, P<0.05) and the middle-lower vaginal angle (179.30°±12.96° vs. 161.73°±10.42°, 179.30°±12.96° vs. 147.01°±12.20°, P<0.05) in the preoperative group were significantly larger than those in the control and postoperative groups. Y-axis coordinates of the endocervical orifice (−52.39±15.63 vs. −59.04±11.49 mm, −52.39±15.63 vs. −65.27±7.25 mm, P<0.05), posterior vaginal fornix (−34.25±13.30 vs. −46.69±11.09 mm, −34.25±13.30 vs. −49.93±8.02 mm, P<0.05), the junction of the middle and lower vagina (−0.48±8.65 vs. −11.34±7.33 mm, −0.48±8.65 vs. −10.11±9.77 mm, P<0.05), and anterior vaginal fornix (−23.14±13.71 vs. −34.68±9.07 mm, −23.14±13.71 vs. −38.64±6.48 mm, P<0.05), as well as the x-axes of the junction of the middle and lower parts of the vagina (26.79±6.71 vs. 19.56±5.24, 26.79±6.71 vs. 17.67±5.81, P<0.05), and vaginal introitus (23.39±7.12 vs. 18.55±4.22, 23.39±7.12 vs. 19.00±4.55, P<0.05) in the preoperative group were smaller than those of the control and postoperative groups. Differences between the control and postoperative groups were not statistically significant (P>0.05).

Conclusions

The current study established that the uterine-vaginal axis of POP women moved backward and downward in the coordinate system, as shown on MRI sagittal images. Further, it moved forward and upwards after surgical repair and more closely resembled that of the control group. The uterine-vaginal axis may provide an evaluation of surgical efficacy in women with POP.

Defining mechanisms of recurrence following apical prolapse repair based on imaging criteria

BACKGROUND

Prolapse recurrence after transvaginal surgical repair is common; however, its mechanisms are ill-defined. A thorough understanding of how and why prolapse repairs fail is needed to address their high rate of anatomic recurrence and to develop novel therapies to overcome defined deficiencies.

OBJECTIVE

This study aimed to identify mechanisms and contributors of anatomic recurrence after vaginal hysterectomy with uterosacral ligament suspension (native tissue repair) vs transvaginal mesh (VM) hysteropexy surgery for uterovaginal prolapse.

STUDY DESIGN

This multicenter study was conducted in a subset of participants in a randomized clinical trial by the Eunice Kennedy Shriver National Institute of Child Health and Human Development Pelvic Floor Disorders Network. Overall, 94 women with uterovaginal prolapse treated via native tissue repair (n=48) or VM hysteropexy (n=46) underwent pelvic magnetic resonance imaging at rest, maximal strain, and poststrain rest (recovery) 30 to 42 months after surgery. Participants who desired reoperation before 30 to 42 months were imaged earlier to assess the impact of the index surgery. Using a novel 3-dimensional pelvic coordinate system, coregistered midsagittal images were obtained to assess study outcomes. Magnetic resonance imaging-based anatomic recurrence (failure) was defined as prolapse beyond the hymen. The primary outcome was the mechanism of failure (apical descent vs anterior vaginal wall elongation), including the frequency and site of failure. Secondary outcomes included displacement of the vaginal apex and perineal body and change in the length of the anterior wall, posterior wall, vaginal perimeter, and introitus of the vagina from rest to strain and rest to recovery. Group differences in the mechanism, frequency, and site of failure were assessed using the Fisher exact tests, and secondary outcomes were compared using Wilcoxon rank-sum tests.

RESULTS

Of the 88 participants analyzed, 37 (42%) had recurrent prolapse (VM hysteropexy, 13 of 45 [29%]; native tissue repair, 24 of 43 [56%]). The most common site of failure was the anterior compartment (VM hysteropexy, 38%; native tissue repair, 92%). The primary mechanism of recurrence was apical descent (VM hysteropexy, 85%; native tissue repair, 67%). From rest to strain, failures (vs successes) had greater inferior displacement of the vaginal apex (difference, -12 mm; 95% confidence interval, -19 to -6) and perineal body (difference, -7 mm; 95% confidence interval, -11 to -4) and elongation of the anterior vaginal wall (difference, 12 mm; 95% confidence interval, 8-16) and vaginal introitus (difference, 11 mm; 95% confidence interval, 7-15).

CONCLUSION

The primary mechanism of prolapse recurrence following vaginal hysterectomy with uterosacral ligament suspension or VM hysteropexy was apical descent. In addition, greater inferior descent of the vaginal apex and perineal body, lengthening of the anterior vaginal wall, and increased size of the vaginal introitus with strain were associated with anatomic failure. Further studies are needed to provide additional insight into the mechanism by which these factors contribute to anatomic failure.

The establishment of a 3D anatomical coordinate system for defining vaginal axis and spatial position

BACKGROUND AND OBJECTIVE

Pelvic organ prolapse (POP), the herniation of the pelvic organs toward the vaginal opening, is a common pelvic floor disorder (PFD) whose etiology is poorly understood. Traditional methods for evaluating POP are often constrained to external vaginal examination, limited to 2D, or have poor reproducibility. We propose a reliable 3D anatomic coordinate system for standardized 3D assessment of pelvic anatomy using magnetic resonance imaging (MRI).

METHODS

The novel 3D anatomic reference system is based on six bony landmarks of the pelvis manually identified in MRI: the ischial spines and the superior and inferior pubic points of the left and right pubic symphysis. The origin of this system is defined as the midpoint of the ischial spines. The reproducibility and applicability of the pelvic coordinate system were evaluated by (1) implementing it in a new method to quantify vaginal position and axis (angulation) in 3D space from MRI segmentations of the vagina and (2) computing the intraclass correlation (ICC) on coordinate system and vaginal measures. The MRI analysis was performed by four non-medically trained observers on five pelvic MRI datasets on approximately five separate occasions.

RESULTS

Overall, all bony landmarks had excellent intra-observer reliability and inter-observer reliability (ICC>0.90); intra-observer reliability was moderate-to-good among the vaginal position parameters (0.5

CONCLUSIONS

The proposed anatomic coordinate system and vaginal analysis approach allow quantitative assessment of pelvic anatomy that is robust to the experience level of the observer. The application of these methods in radiographic studies will give new insight into the underlying anatomic changes involved in the pathogenesis of POP and other PFDs and help better understand their etiology.

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Key Words

• 3D Coordinate System
• MRI
• Pelvic Organ Prolapse
• Pelvis
• Reliability Analysis
• Vagina

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MESH Headings

• Female
• Humans
• Magnetic Resonance Imaging
• Pelvic Organ Prolapse
• Pelvis
• Reproducibility of Results
• Vagina/diagnostic imaging

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Grants

• UG1 HD069006 NICHD NIH HHS

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Affiliation(s)

Deanna C E Sinex Department of Bioengineering, University of Pittsburgh, 406 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15260, United States
Shaniel T Bowen Department of Bioengineering, University of Pittsburgh, 406 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15260, United States
Ahmed Kashkoush Cleveland Clinic Foundation, Cleveland, OH, United States
Arianna Rosemond 4350 Northern Pike #150, Monroeville, PA, United States
Danielle Carter Silver Spring, MD, United States
Prahlad G Menon Department of Bioengineering, University of Pittsburgh, 406 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15260, United States
Pamela A Moalli Department of Bioengineering, University of Pittsburgh, 406 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15260, United States; Department of Obstetrics, Gynecology & Reproductive Sciences, University of Pittsburgh Medical Center, Magee Women's Research Institute, Pittsburgh, PA, United States
Steven D Abramowitch Department of Bioengineering, University of Pittsburgh, 406 Benedum Hall, 3700 O'Hara Street, Pittsburgh, PA 15260, United States.

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Vaginal axis on MRI after laparoscopic lateral mesh suspension surgery: a controlled study

INTRODUCTION AND HYPOTHESIS

Laparoscopic lateral mesh suspension (LLMS) has emerged as a practical, safe, and feasible alternative to sacrocolpopexy (SCP) for treating female genital apical prolapse. Although several prior studies have reported changes in the vaginal axis in women who have undergone SCP or sacrospinous ligament fixation (SSLF) surgery for prolapse, there is a lack of data on changes in the vaginal axis after LLMS. This study was aimed at investigating the level of anatomical correction following LLMS and comparing the vaginal axis on magnetic resonance imaging (MRI) in patients with apical genital prolapse.

METHODS

Patients who underwent LLMS and a nulliparous control group were included in this observational prospective case-control study. MRI was performed on the control group and the study group pre- and postoperatively. The angle between the pubococcygeal line and the lower vaginal segment, the angle between the levator plate and the pubococcygeal line, and the angle between the lower and upper vaginal segments were measured and compared.

RESULTS

The angles measured between the pubococcygeal line and the lower vaginal segment and between the levator plate and the pubococcygeal line were significantly lower in the preoperative than in the postoperative measurements (p < 0.001). All angles were found to be similar in the nulliparous women and in the patients following LLMS surgery. The Pelvic Organ Prolapse Symptom Score (POP-SS) score decreased significantly after the operation (p < 0.001).

CONCLUSION

The vaginal axis was found to be near-normal in patients who underwent LLMS.