2.1 Patients
This observational cohort study represents a retrospective series of 135 patients treated by biomechanical reconstruction for moderate and severe POP between January 2021 and May 2022 in the Urogynecology department of The First Affiliated Hospital of Kunming Medical University. This study was approved by the Ethics Committee of the First Affiliated Hospital of Kunming Medical University [IRB No. (2022) Ethical Review L No.33,2022.04.27] and the patients were contacted and agreed to follow-up examinations.
Inclusion criteria: (i) Moderate to severe POP (stage 3 or greater) as assessed by POP-Q scale; (ii) Consent for pelvic floor biomechanical reconstruction surgery and pelvic floor ultrasound. Exclusion criteria: (i) Acute infection and severe comorbidities that preclude the procedure; (ii) History of pelvic radiation therapy; (iii) Use of immunosuppressive drugs; (iv) Presence of psychiatric and psychological disorders; (v) Cervical elongation (cervical length > 33.8 mm). All patients underwent a standardized technique performed by the same surgeon after obtaining informed consent.
The following data were collected for each patient: patient characteristics (age, body mass index (BMI), menopausal status, parity, sexual activity, prior vaginal deliveries, surgical history, and comorbidities), functional symptoms, and degree of POP. Intraoperative and postoperative complications, blood lost, operative duration, and duration of postoperative hospitalization were documented. Systematic postoperative clinical examinations were performed at 3months, 6 months, and 12 months. The operative results were assessed form both anatomic and functional perspectives. Clinical assessment alone is an inadequate tool to evaluate pelvic floor function and anatomy(17). Transperineal ultrasound is a valuable and objective method in urogynecological evaluation. It allows for the assessment of pelvic floor anatomy, its functions and dysfunctions, the selection of appropriate treatment, and the analysis of changes after surgical intervention(18, 19). Pelvic floor ultrasound was repeated three months after the procedure.
Anatomic cure was the first primary outcome and examinated with POP-Q staging and sonographic imaging. Patient satisfaction was the second primary outcome and was assessed using the PGI-I scale. Patients with a PGI-I rating of “very much better” or “much better” were considered satisfied. Secondary outcomes were rates for recurrence rate, reoperation rate and complication. Recurrent prolapse was defined as postoperative stage ≥2, regardless of reported symptoms. Mesh-related complications were classified using the joint International Urogynecological Association/International Continence Society (IUGA/ICS) complication classification calculator(20).
2.2 Surgery technique
The procedure was performed under general anesthesia. The surgical technique was divided into two principle steps. The first step was anterior compartment mesh inlay with the principle of tension-free suspension. The second step was posterior colporrhaphy and reconstruction of PB. We demonstrate its steps with a video.
Step1 A polypropylene mesh(Pelvimesh®; Herniamesh®, Chivasso, Italy) was cut to obtain four long arms (approximately 2×5cm) and a central rectangular part (approximately 5-8×5cm) (Fig. 1a). Water separation was achieved by injecting 60-120 ml of 0.25-0.5:1000 epinephrine saline into the anterior vaginal wall (Fig. 1b). The entire anterior vaginal wall was incised from the inferior vaginal urethral sulcus to 2 cm anterior to the cervix (Fig. 1c). Separate superficial and deep branch puncture tunnels were created along the vesico-vaginal hiatus. Using the descending pubic branch as the anatomical landmark, the upper puncture point was located 0.5 cm immediately outside the pubic symphysis at the uppermost point of the descending pubic branch, while the lower puncture point was positioned 0.5 cm below the sciatic branch (Fig. 1d and Fig. 2). Introducer needles were passed sequentially through the skin, subcutaneous tissue, thigh fascia lata, adductor muscle tendons, upper pelvic septum, and the ATFP. The mesh was placed by retracting the introducer needles (Fig. 1e-f). The mesh was secured with 2-0 absorbable sutures at each corner and laid flat from the suburethral sulcus to 1 cm in front of the bladder neck (Fig. 1g). Subsequently, the mesh was embedded, and the vaginal mucosa was folded using 3-0 barbed wire.
Step2 The reserved diameter of the vagina was about 3 cm. The reserved diameter of vagina in elderly women without sex activities could be smaller properly. A Hexagon incision was made from the outer opening of the posterior vaginal wall to the pelvic diaphragm (Fig. 1h-i). The posterior vaginal wall was dissected proximally to the cervix and laterally to the pararectal attachments to the pelvic sidewall (Fig. 1j). The levator plate and torn levator muscle were sutured with 2-0 herringbone sutures starting from 2 cm below the cervix. Additionally, the mucosa below the cervix was sutured to form a ridge on the posterior vaginal wall, reconstructing the posterior fornix (Fig. 1k). The levator plate and torn levator muscle were further reinforced to reduce the levator fissure and lengthen the perineal body(Fig. 1l). Finally, the perineum and external anal sphincter were repaired (Fig. 1m-n). Intraoperative and postoperative measurements showed a significant lengthening of the perineal body length (Fig. 3). The mesh was carefully tightened and trimmed until the vagina achieved a natural state (Fig. 1o).
2.3 Transperineal pelvic floor ultrasonography
2.3.1 Instrument
The General Electric Voluson E10 color Doppler ultrasound diagnostic instrument with RIC5-9-D volumetric probe, operating at a frequency of 5-10 MHz and a mechanical index of 0.12-0.18, was utilized. 2D and 4D images were acquired and stored in Valsalva action state. All image data were exported to an ultrasound image workstation, and the 4DView off-machine analysis software was used to reconstruct and process the data.
2.3.2 Method
All subjects were instructed to empty their stool and bladder prior to the examination and assume a supine position. An appropriate amount of coupling agent was applied to the outside of the probe. The probe was gently placed in the perineum immediately below the inferior border of the pubic symphysis. The level of the posterior inferior border of the pubic symphysis was used as the reference point, with below the pubic symphysis recorded as negative and above as positive.
Images of the important anatomical structures of the pelvic floor, including the pubic symphysis, the bladder and urethra, the vagina, the rectum, the distal part of the anal levator and the anal canal, were selected to be clearly displayed in the median sagittal plane. Images were acquired at rest and at maximum Valsalva, and the position of the bladder neck at rest, the position of the bladder neck at maximum Valsalva, the Urethral Rotation Angle (URA), the Restrovesical Angle (RVA), the Levator Hiatus Area (LHA) in maximum Valsalva state, and the Bladder Neck Descent (BND) were measured and recorded(Fig. 4). The ultrasound parameters were compared between the subject groups and subjected to statistical analysis.
2.4 Statistical analyses
Data analysis was performed using SPSS version 22.0. Continuous variables were reported as means±standard deviation and medians. Categorical variables were reported as number and relative proportion.