The use of curved vs. straight instruments in single port access surgery, on standardized box trainer tasks

BACKGROUND: Single-port access (SPA) surgery is a novel surgical technique to create nearly "scarless" surgery. SPA surgery appears to be safe and feasible, but the exposure and handling of tissue may not be optimal. Therefore, the performance of SPA surgery with different instruments used and conventional laparoscopy is compared. METHODS: Fifteen participants (>50 laparoscopic procedures) performed three basic tasks (translocation, clip & cut, and tissue dissection, based on the fundamentals of laparoscopic surgery) in the box trainer in laparoscopy and SPA settings with both (conventional) crossed and curved instruments. All participants completed a questionnaire, which asked their opinion on the use of instruments and preference. RESULTS: Translocation was performed significantly faster in both laparoscopy and SPA crossed than SPA curved (means, 130.3 and 137.7 vs. 170.7 sec; p < 0.001 and p = 0.005). The errors also were less in laparoscopy and SPA crossed (means, 0.9 and 1.2 vs. 1.6), but not significant. The time to complete the dissection was almost equal between laparoscopy and SPA curved settings, but took longer for SPA crossed, although not significantly (148.1 and 150.8 vs. 179.5 sec). The errors only differed significantly between laparoscopy and SPA crossed (means, 0.5 vs. 1.27; p = 0.044). Fourteen participants still favored conventional laparoscopy and one SPA curved. They also thought SPA curved was better than crossed (means, 3.6 vs. 2.47; p = 0.003) and that exposure is superior in curved (means, 3.4 vs. 2.27; p = 0.002). CONCLUSIONS: Although conventional laparoscopy may appear most effective for proper dissection and exposure of tissue, single-port access surgery shows potential. Especially in the tissue dissection task, there is no significant difference in time or errors between conventional laparoscopy and SPA surgery, using specially designed curved instruments. Although the participants favor conventional laparoscopy, this could evolve to a more accepting mind when SPA surgery becomes more available and used in the clinical setting.