2D versus 3D laparoscopic total mesorectal excision: a developmental multicentre randomised controlled trial

Abstract

Aims: The role of laparoscopy in rectal cancer has been questioned. 3D laparoscopic systems are suggested to aid optimal surgical performance but have not been evaluated in advanced procedures. We hypothesised that stereoscopic imaging could improve the performance of laparoscopic total mesorectal excision (TME).

Methods: A multicentre developmental randomised controlled trial comparing 2D and 3D laparoscopic TME was performed (ISRCTN59485808). Trial surgeons were colorectal consultants that had completed their TME proficiency curve and underwent stereoscopic visual testing. Patients requiring elective laparoscopic TME with curative intent were centrally randomised (1:1) to 2D or 3D using Karl Storz IMAGE1 S D3-Link™ and 10-mm TIPCAM®1S 3D passive polarising laparoscopic systems. Outcomes were enacted adverse events as assessed by the observational clinical human reliability analysis technique, intraoperative data, 30-day patient outcomes, histopathological specimen assessment and surgeon cognitive load.

Results: 88 patients were included. There were no differences in patient or tumour demographics, surgeon stereopsis, case difficulty, cognitive load, operative time, blood loss or conversion between the trial arms. 1377 intraoperative adverse events were identified (median 18 per case, IQR 14-21, range 2-49) with no differences seen between the 2D and 3D arms (18 (95% CI 17-21) vs. 17 (95% CI 16-19), p = 0.437). 3D laparoscopy had non-significantly higher mesorectal fascial plane resections (94 vs. 77%, p = 0.059; OR 0.23 (95% CI 0.05-1.16)) but equal lymph node yield and circumferential margin distance and involvement. 30-day morbidity, anastomotic leak, re-operation, length of stay and readmission rates were equal between the 2D and 3D arms.

Conclusion: Feasibility of performing multicentre 3D laparoscopic multicentre trials of specialist performed complex procedures is shown. 3D imaging did not alter the number of intraoperative adverse events; however, a potential improvement in mesorectal specimen quality was observed and should form the focus of future 3D laparoscopic TME trials.

Keywords: 3D; Laparoscopic; Rectal cancer; Three-dimensional; Total mesorectal excision; Trial.

Fig. 1

Trial CONSORT diagram. Three patients did not proceed to surgery. Four conversions were seen and with other exclusions 77 videos were available for OCHRA analysis

Fig. 2

A–C Intraoperative error data. A Box and whisker plot, B histogram, C errors per operative phase. No differences in the distributions are seen. Errors were seen to take place across all phases of the operation justifying the approach to review entire cases. Studying pelvic performance alone would have missed 50% of identified adverse events

Fig. 3

NASA-TLX with medians displayed (2D—dashed line, 3D—solid line). Overall low demands were reported in both arms and were not influenced by the use 2D or 3D imaging (p = 0.59, 0.825, 0.64, 0.942, 0.270 and 0.286, respectively)

Fig. 4

Histopathological assessment of the mesorectal surgical plane. Despite inclusion in the UK Royal College of Pathologists colorectal cancer dataset was not given in eight (9.4%) reports. When these are excluded a clinically significant increase in mesorectal fascial plane surgery is seen (87% overall, 77% vs. 94%, OR 0.23 (95% CI 0.05–1.16), p = 0.059)