Total Extraperitoneal Anterior Rectopexy (TEAR) : Initial experience using Mantra Robotic platform and Endoluminal Fixator device

Purpose/Background: Ventral mesh rectopexy, current preferred minimally invasive approach for rectal prolapse entails entering the peritoneum with inherent risks of vascular/visceral injury, postoperative adhesions, besides sacral tack fixation and mesh related issues. Laparoscopic Total extraperitoneal anterior rectopexy (L-TEAR), recently reported by us (DOI: 10.1007/10151-025-03281-6) addresses most of these concerns, avoiding posterior rectal dissection. We present the initial experience of TEAR using Mantra robotic platform and endoluminal fixator.

Methods/Interventions: This prospective single-centre study included 10 patients (7 males; mean 47 years) of procedentia between December 2024 and 2025, having a BMI < 28 kg/m² with no prior abdominal surgery. The procedure was performed in general anaesthesia (modified lithotomy) using Mantra Robotic platform. Extraperitoneal space was created with a 10 mm camera port, inserted 1 cm left of umbilicus. The space was expanded using CO₂ insufflation, with two 5mm working ports placed lateral to linea semilunaris on either sides. Endoluminal fixator with transparent silicone gel head was inserted transanally to reduce the rectum and transilluminate it for identification in this space. Left ureteric catheterization with ICG injection enabled its intraoperative visualization. The rectum was dissected from the bladder with help of endoluminal fixator inserted from below. The prolapsed rectum was fixed to the undersurface of anterior abdominal wall using 4-6 seromuscular PDS 2-0 sutures through anterior rectal wall with help of robot. The free ends of these sutures left inside were delivered outside the abdominal wall by suture passer, starting at the iliopectineal ligament upwards and tied off serially. A 2*10 cm dual mesh was used in 4 cases to reinforce this fixation. Subjective (SMIS, ODS, QOL) and objective variables (sigmoidoscopy, MR defecography, manometry) were assessed preoperatively and at 6 months after surgery. Cost analysis was included.

Results/Outcomes: Mean operative time, blood loss, hospital stay was 180 mins, 115 mL, 3 days, respectively. The Mantra platform provided superior surgeon ergonomics and comfort in limited extraperitoneal pelvic space compared to conventional laparoscopy. It also gives enhanced 3D visualization and magnification in the confined space. The articulated wristed instruments facilitated precise dissection and ease of suturing in the narrow male pelvis, with improved delineation of extraperitoneal pelvic anatomy. Additionally, the Mantra system has significant cost benefits (1019 USD per case) over traditional robotic platforms (4100 USD), increasing accessibility in third world countries. At a median follow-up of 6 months no recurrences were observed. There were no conversions, major complications, or mortality. Minor complications included transient hematuria in 2 patients, which resolved conservatively. Functional outcomes including SMIS

(from 17.5+/- 2.5 to 14.4 +/-2.6 ; p < 0.045) and ODS (from 16.4 +/- 2.9 to 7.8 +/- 3.6 ; p < 0.0002) showed improvement in interim analysis.

Conclusion/Discussion: Robotic TEAR avoids peritoneal entry, its associated risks, provides option of not using a mesh and avoids sacral fixation. The use of robot and fixator device provide superior ergonomics, enhanced visualization and dexterity in confined extraperitoneal pelvic space besides significant cost benefits. This technique is feasible, safe, with promising early outcomes, requiring long-term validation in a larger patient cohort.

Extra-peritoneal pelvic anatomy before and after mesh placement
Seromuscular sutures placed through extraperitoneal anterior rectum for suture rectopexy ( without mesh )