Three-Dimensional vs Two-Dimensional Minimally Invasive Surgery. A comparison of the visual work load and surgical outcomes

BACKGROUND Three-dimensional (3D) imaging, a recent technical innovation in laparoscopic surgery, has been introduced to enhance depth perception and facilitate operations. The clear benefit of the 3D laparoscopy has never been tested. Some concerns emerged regarding the possible negative effects over the visual system in those surgeons who performed 3D surgery every day. 3D laparoscopy has been validated both in “in-vitro” and “in-vivo” (clinical) settings. All survey done in laparoscopic simulator comparing surgical exercise (suturing, peg transfer, cutting) performed with 2D or 3D system reported better results in the second group, regardless the surgeon experience. Less data is disposable in the clinical setting, but with same conclusions. The use of 3D technology needs passive or active polarized glasses. Optometric tests, objective exams (RMN or EEG) and subjective questionnaires have been widely used to evaluate the alterations in the visual system utilizing the 3D technology. Each test concluded that 3D technology causes alteration in the EEG waves, but how long these alterations last is still unknown. AIM The aim of this study was to evaluate the possible benefit of using the 3D technology in terms of surgical outcomes (study 1) and to evaluate the alterations over the visual system operating in 3D laparoscopy (study 2). MATERIALS AND METHODS The study was a single-center prospective observational clinical trial, divided in two sub-study with a single patients-population. Participants included patients aged 18 years old and above, eligible for colorectal resections for neoplastic or inflammatory diseases. Four experienced surgeons in colorectal and laparoscopic surgery participated in the study. Each surgeon followed the standard laparoscopic surgical rules performing the different type of colorectal resection, regardless the study subgroup. Data were collected at the pre-operative clinic, during surgery, during the hospitalizations and at the short term follow-up (30th days). For each study, there was a primary endpoint: 1. Primary endpoint for Study 1: incidence of Clavien grade 3, 4 and 5 postsurgical complications in patients undergone 3D colorectal resection; 2. Primary endpoint for Study 2: to grade the visual work load of surgeons operating with 3D screens and glasses. At the end of each procedure (2D or 3D) the first surgeon had to fill in two different subjective questionnaire (the NASA task load index questionnaire and the Simulator Sickness questionnaire) to grade the visual sickness felt during the operation. RESULTS From January 2015 to September 2017, 313 patients were enrolled in the study: 82 in the 2D group, 231 in the 3D group. STUDY 1: Colorectal cancer was the main indication for surgery (n 235, 75.1%), followed by colonic diverticulosis, benign polyposis and inflammatory bowel diseases (IBD), respectively 43 (13.8 %), 25 (7.9 %) and 10 (3.2 %). Age, sex, ASA score were comparable between the two groups. The median operative time showed no statistically significant difference between the 3D and 2D groups (p 0.611). Less drains were positioned at the end of the 3D operations comparing with 2D procedures (p 0.013). The stapled anastomosis was the most frequent performed over other techniques. The other intra-operative findings showed no significant difference between the two study groups. The median hospitalization and the reoperation rate showed no difference between the two groups. STUDY 2: The statistical analysis done over all 313 cases divided in 2D and 3D did not reveled significant difference of the visual work scored by the NASA TLX. Data emerging from the SSQ questionnaire reveled no case of moderate or severe symptoms in both groups. CONCLUSIONS 3D laparoscopic surgery had the same postoperative results of the 2D standard laparoscopy. The more frequent intra-abdominal anastomosis in the 3D group might suggest a more safeness felt by the surgeon using the new technology. The NASA TLX and the SSQ questionnaire did not reveled significant difference of the visual work between 2D and 3D vision.