One-port vs. three-port diagnostic vitrectomy for posterior segment diseases of unknown origin

Purpose: To compare the safety and the effectiveness of one-port vs. three-port diagnostic vitrectomy in undiagnosed cases of posterior segment inflammation. Methods: We retrospectively collected data from 80 consecutive diagnostic vitrectomies performed using a one-port (n = 40) or a three-port approach (n = 40). Cases of suspected postoperative endophthalmitis were not included in the study. Several variables were compared among groups, including length of surgery, postoperative best-corrected visual acuity (BCVA), diagnostic success and surgical complications. Results: The mean duration of surgery was shorter in the one-port group when compared to the three-port group (15 ± 8 min vs. 49 ± 30; p = 0.0001). The patients were observed for a mean follow-up of 19 months (range 1-84). In the one-port group, the mean BCVA improved from 1.31 ± 0.96 to 0.57 ± 0.59 logarithm of minimum resolution (LogMAR) (p = 0.0009). In the three-port group, BCVA improved from 0.98 ± 0.76 to 0.51 ± 0.76 LogMAR (p = 0.0005). The difference in mean postoperative BCVA between groups was not significative at the last follow-up. One-port vitrectomy yields to a final diagnosis in 80% of the cases, and three-port vitrectomy in 48%. Most of the one-port vitrectomies were carried out under topical anesthesia. After surgery, in both groups three eyes developed a retinal detachment. Conclusions: In this pilot study, the one-port diagnostic vitrectomy has proven to be as effective and safe as the three-port approach, allowing a reduction in surgical times. One-port diagnostic vitrectomy might be considered as the first option for those cases where more complex surgical procedures are not needed.