Dynamic magnetic resonance imaging for assessment of minimally invasive pelvic floor reconstruction with polypropylene implant

ACR Appropriateness Criteria® Pelvic Floor Dysfunction in Females

Pelvic floor disorders including pelvic organ prolapse (POP), urinary dysfunction, defecatory dysfunction, and complications after pelvic floor surgery are relatively common in the female population. Imaging tests are obtained when the initial clinical evaluation is thought to be incomplete or inconclusive or demonstrates findings that are discordant with patients' symptoms. An integrated imaging approach is optimal to evaluate the complex anatomy and dynamic functionality of the pelvic floor. Fluoroscopic cystocolpoproctography (CCP) and MR defecography are considered the initial imaging tests of choice for evaluation of POP. Fluoroscopic voiding cystourethrography is considered the initial imaging test for patients with urinary dysfunction. Fluoroscopic CCP and MR defecography are considered the initial imaging test for patients with defecatory dysfunction, whereas ultrasound pelvis transrectal is a complementary test in patients requiring evaluation for anal sphincter defects. MRI pelvis without and with intravenous contrast, MRI pelvis with dynamic maneuvers, and MR defecography are considered the initial imaging tests in patients with suspected complications of prior pelvic floor surgical repair. Transperineal ultrasound is emerging as an important imaging tool, in particular for screening of pelvic floor dysfunction and for evaluation of midurethral slings, vaginal mesh, and complications related to prior pelvic floor surgical repair. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

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.

Comparison of the Axes and Positions of the Uterus and Vagina Between Women With and Without Pelvic Floor Organ Prolapse

Purpose

To analyze the role of the axial positions of the uterus and vagina in providing pelvic floor support, encourage evaluations of pelvic floor function, and improve the understanding of the pathogenesis of pelvic organ prolapse.

Methods

The lengths and angles of the upper, middle, and lower axes of the vagina, uterine body, and cervix of 81 women with prolapse (prolapse group) and 57 women without prolapse (non-prolapse group) were measured and compared using magnetic resonance images. The pelvic inclination correction system (PICS) line was also compared between the groups. The coordinate parameters of the anatomical points of the uterus and vagina were measured, and their positions were analyzed.

Results

In the prolapse group, the uterine body-cervical angle, cervical-upper vaginal angle, uterine body-PICS line angle, cervical-PICS line angle, and lower vaginal-PICS line angle were smaller (p < 0.05) and the middle-lower vaginal angle, upper vaginal-PICS line angle, and middle vaginal-PICS line angles were larger (p < 0.05) than those in the non-prolapse group. The cervical length was longer (p < 0.05) and the middle and lower vaginal lengths were shorter (p < 0.05) in the prolapse group. The coordinate system revealed that the uterine and vaginal axes were shifted backward and downward in the prolapse group.

Conclusion

Patients in the prolapse group were more likely to have retroversion and retroflexion of the uterus than those in the non-prolapse group. The vagina was shortened, turned forward, and straightened, and the uterus and vagina were shifted backward and downward in the prolapse group. Changes in the axial position of the uterus and vagina are important mechanisms of pelvic floor organ prolapse.

MR defecography technique: recommendations of the society of abdominal radiology's disease-focused panel on pelvic floor imaging

PURPOSE

To develop recommendations for magnetic resonance (MR) defecography technique based on consensus of expert radiologists on the disease-focused panel of the Society of Abdominal Radiology (SAR).

METHODS

An extensive questionnaire was sent to a group of 20 experts from the disease-focused panel of the SAR. The questionnaire encompassed details of technique and MRI protocol used for evaluating pelvic floor disorders. 75% agreement on questionnaire responses was defined as consensus.

RESULTS

The expert panel reached consensus for 70% of the items and provided the basis of these recommendations for MR defecography technique. There was unanimous agreement that patients should receive coaching and explanation of commands used during MR defecography, the rectum should be distended with contrast agent, and that sagittal T2-weighted images should include the entire pelvis within the field of view. The panel also agreed unanimously that IV contrast should not be used for MR defecography. Additional areas of consensus ranged in agreement from 75 to 92%.

CONCLUSION

We provide a set of consensus recommendations for MR defecography technique based on a survey of expert radiologists in the SAR pelvic floor dysfunction disease-focused panel. These recommendations can be used to develop a standardized imaging protocol.

Restored pelvic anatomy is preserved after laparoscopic and robot-assisted ventral rectopexy: MRI-based 5-year follow-up of a randomized controlled trial

AIM

Our aim was to compare the long-term anatomical outcomes between robot-assisted ventral mesh rectopexy (RVMR) and laparoscopic ventral mesh rectopexy (LVMR) for external or internal rectal prolapse.

METHOD

This study is a follow-up of a single-centre randomized controlled trial (RCT). Thirty patients were randomly allocated to RVMR (n = 16) or LVMR (n = 14). The primary end-point was maintenance of the restored pelvic anatomy 5 years after the operation, as assessed by magnetic resonance (MR) defaecography. Secondary outcome measures included the Pelvic Organ Prolapse Quantification (POP-Q) measures and functional results assessed using symptom questionnaires.

RESULTS

Twenty-six patients (14 RVMR and 12 LVMR) completed the 5-year follow-up and were included in the study. The MRI results, POP-Q measurements and symptom-specific quality of life measures did not differ between the RVMR and LVMR groups. The MRI measurements of the total study population remained unchanged between 3 months and 5 years. In the Pelvic Floor Distress Inventory (PFDI-20), the RVMR group had lower symptom scores (mean 96.0, SD 70.7) than the LVMR group (mean 160.6, SD 58.9; P = 0.004). In the subscales of pelvic organ prolapse (POPDI-6) (mean 23.2, SD 24.3 vs mean 52.4, SD 22.4; P = 0.001) and the Colorectal-Anal Distress Inventory (CRADI-8) (mean 38.4, SD 23.3 vs mean 58.6, SD 25.4; P = 0.009), the patients in the RVMR group had significantly better outcomes.

CONCLUSION

After VMR, the corrected anatomy was preserved. There were no clinically significant differences in anatomical results between the RVMR and LVMR procedures 5 years after surgery based on MR defaecography. However, functional outcomes were better after RMVR.

MR defecography in the assessment of anatomic and functional abnormalities in stress urinary incontinence before and after pelvic reconstruction

PURPOSE

Magnetic resonance defecography (MRD) was used to evaluate anatomic and functional pelvic floor disorders in women with stress urinary incontinence (SUI) before and after midurethral sling (MUS) intervention.

METHOD

We performed MRD in both SUI patients and continent controls. Static MR was used to describe the anatomic abnormalities in levator ani muscle and periurethral ligaments (PUL). Dynamic MR was used to depict the function of the urethra and pelvic floor. We compared the MRD parameters between the SUI patients and continent controls before surgery. For SUI patients, dynamic MR images evaluated the functional changes of the urethra and pelvic floor after surgery.

RESULTS

In SUI group, 75.8 % have PUL defects, 65.7 % discontinuity or complete loss of pubococcygeal muscle, as compared to the continent groups (p < 0.01). There was no significant difference between the perimenopausal volunteers and SUI patients in the puborectalis defection (p > 0.05). The dynamic MR showed the urethral hypermobility, functional urethra shortening, bladder neck funneling, urethra opening and cystocele were significantly associated with SUI patients (p < 0.01). Postoperative MR indicated that SUI patients after MUS had a lower risk of bladder funneling and urethral opening at the defection phase (p < 0.01), but no significant difference in urethral hypermobility or pelvic floor prolapse was seen (p>0.05).

CONCLUSIONS

MRD with high-resolution and defecation phases provides a detailed anatomic and functional evaluation of the pelvic floor in female SUI before and after pelvic reconstruction.

Transvaginal Mesh and Transanal Resection to Treat Outlet Obstruction Constipation Caused by Rectocele

Background

The aim of this study was to evaluate the curative effect of transvaginal mesh repair (TVMR) and stapled transanal rectal resection (STARR) in treating outlet obstruction constipation caused by rectocele.

Material/Methods

Patients who had outlet obstruction constipation caused by rectocele were retrospectively analyzed and 39 patients were enrolled the study. Patients were assigned to either the TVMR or STARR group. Postoperative factors such as complications, pain, recurrence rate, and operative time were compared between the 2 groups.

Results

Total effective rate was 100% in both groups. No long-term chronic pain occurred and discomfort rate of tenesmus was higher in the STARR group than in the TVMR group. Postoperative defecography showed that the rectocele depth was significantly reduced, and the prolapse of the rectal mucosa and the lower rectal capacity was also decreased. Four cases had mesh exposure in the TVMR group and 2 cases in the STARR group had anastomotic bleeding after the surgery.

Conclusions

For outlet obstruction constipation caused by rectocele, TVMR and STARR both obtained satisfactory results. Although TVMR is complex with longer operative time and hospitalization period, its long-term effect is better than that of STARR.

ACR Appropriateness Criteria pelvic floor dysfunction

Pelvic floor dysfunction is a common and potentially complex condition. Imaging can complement physical examination by revealing clinically occult abnormalities and clarifying the nature of the pelvic floor defects present. Imaging can add value in preoperative management for patients with a complex clinical presentation, and in postoperative management of patients suspected to have recurrent pelvic floor dysfunction or a surgical complication. Imaging findings are only clinically relevant if the patient is symptomatic. Several imaging modalities have a potential role in evaluating patients; the choice of modality depends on the patient's symptoms, the clinical information desired, and the usefulness of the test. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions; they are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals, and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

MRI findings before and after prolapse surgery

BACKGROUND

Therapeutical outcome after prolapse surgery is evaluated using a standardized grading system based on maximum prolapse extent, which might not provide the full picture of the patient's subjective outcome. We therefore applied an evaluation method, which is detached from a grading system.

PURPOSE

To evaluate the impact of pelvic organ mobility in dynamic magnetic resonance imaging (MRI) before and after mesh-repair surgery in patients with symptomatic pelvic organ prolapse.

MATERIAL AND METHODS

To obtain measurements, we performed parasagittal T2-weighted turbo spin echo sequence at rest (TR, 3460 ms; TE, 85 ms; matrix, 512; slice thickness [ST], 5 mm), parasagittal T2-weighted true fast imaging with steady-state precession (TrueFISP) single-shot sequence during straining (TR, 397.4 ms; TE, 1.5 ms; matrix, 256; ST, 8 mm), and parasagittal T2-weighted TrueFISP sequence at maximum strain (TR, 4.3 ms; TE, 2.15 ms; matrix, 256; ST, 5 mm) at 1.5 T MRI. Pelvic organ prolapse (anatomical landmarks: bladder, cervix, pouch, rectum) was measured perpendicularly with reference to the pubococcygeal and the midpubic line. Pelvic organ mobility was defined as the difference between the measured distance at rest and at maximum strain for each anatomical landmark. All patients underwent mesh-repair procedure. Eighty patients could be included in this short-term follow-up study. Due to the physical diagnosis of pelvic organ prolapse, 51 underwent anterior mesh repair, 16 underwent posterior mesh repair, and 13 underwent total mesh repair. Surgery was performed by one surgeon, using mesh implants from several manufacturers.

RESULTS

Median values of maximum organ prolapse for bladder, cervix, pouch, and rectum preoperatively were 2.54 cm, 0.33 cm, 2.47 cm, and 0.32 cm, respectively, and 12 weeks postoperatively 0.87 cm, -1.79 cm, 1.49 cm, and 0.49 cm, respectively. Highly significant improvement (P < 0.001) of pelvic organ mobility was observed in the treated compartment at 4- and 12-week follow-up. Physical evaluation 12 weeks after mesh-repair showed an asymptomatic POP-Q stage I, if any.

CONCLUSION

Dynamic MRI is useful in visualizing the maximum extent of pelvic organ prolapse, as the evaluation of pelvic organ mobility documents the intraindividual therapeutic outcome detached from a grading system based on maximal prolapse values.

[Pelvic floor disorders from the surgeon's viewpoint]

Pelvic floor disorders present very differently with regard to symptoms and manifestation. Both diagnostic and treatment options require specific experience and an interdisciplinary approach. Diagnostic work-up is primarily based on medical history, physical examination and procto-rectoscopy. Furthermore, endosonography and perineal sonography have also gained importance. In almost all cases following these basic examinations conservative therapy options should be considered. As the interdisciplinary concept is very important, for careful diagnosis of pelvic floor disorders it became crucial to find an adequate form of treatment. Every decision for surgical therapy should not only focus on the results of previous examinations but should also consider the individual situation of each patient. In pelvic floor disorders a large variety of symptoms are confronted with a vast number of different and often highly specific procedures. The decisions on who to treat and how to treat are not only based on individual patient requests and desires but also on the experience and preference of the surgeon.

Magnetic resonance imaging of abdominal versus vaginal prolapse surgery with mesh

INTRODUCTION AND HYPOTHESIS

We compared two surgical approaches in patients with symptomatic prolapse of the vaginal apex with normal controls by analyzing pelvic landmark relationships measured using magnetic resonance imaging (MRI) before and after surgery.

METHODS

In this prospective multicenter pilot study involving 16 participants, nulliparous controls (n = 6) were compared with ten parous (3.0 ± 1.0) women with uterine apical prolapse equal to or greater than stage 2. Group A (n = 5) underwent abdominal sacral colpopexy with monofilament polypropylene mesh and group B (n = 5) with vaginal mesh kit repair (Total ProLift). Subtotal hysterectomy was performed in all group A and no group B women. All patients underwent preoperative and 3-month postoperative Pelvic Organ Prolapse Quantification (POP-Q) and dynamic MRI. Comparison of MRI pelvic angles and distances was performed and analyzed by Mann-Whitney rank sum test and chi-square test.

RESULTS

Vaginal apical support is similar at 3 months for abdominal sacral colpopexy (ASCP) and ProLift by POP-Q examination and MRI analysis. In both treatment groups, the postoperative POP-Q point C and MRI parameters were similar to nulliparous controls at 3 months.

CONCLUSIONS

Anatomic outcomes for ASCP compared with ProLift were similar at 3 months in terms of vaginal apical support by POP-Q and MRI analysis. Continued comparative analysis of postoperative support with objective imaging seems warranted.