Magnetic resonance imaging pelvimetry predicts the technical difficulty of rectal surgery

The relationships between the pelvimetry and technical difficulties in performing rectal surgery for mid-low rectal cancer remain unclear.Two hundred and twenty-one cases of mid-low rectal cancer patients who underwent sphincter-preserved total mesorectum excision (TME) were analyzed. The data of the pelvimetry and the relative position between trocar site and tumor were measured with magnetic resonance imaging (MRI).Univariate analysis showed that the interspinous diameter, the sacrococcygeal distance, and the angle of sacral promontory inclination were significantly associated with the technical difficulty during laparoscopic surgery, but only the interspinous diameter remained an independent risk factor in multivariate analysis. The simulated trocar angle θ was an independent risk factor affecting the operation time during laparoscopic surgery, simulated trocar angle η was significantly related to intraoperative blood loss in both laparoscopic surgery and transanal TME (taTME) surgery groups.Interspinous diameter can predict difficulty in laparoscopic surgery and may provide useful information for preoperative planning and consideration of approach.