Redetachment after pars plana vitrectomy - An analysis of the incidence of entry site breaks

Purpose: To determine the incidence of primary anatomical failure or recurrent retinal detachment presumed to be associated with entry site breaks in patients undergoing pars plana vitrectomy. Methods: All patients undergoing pars plana vitrectomy at Moorfields Eye Hospital in a 6 month period were entered into the study and followed prospectively to determine the incidence of primary failure or retinal redetachment and to determine and analyze potential risk factors such as proliferative vitreo-retinopathy (PVR), diabetis, type and location of detachment. Results: 109 vitrectomies were reviewed, 24 redetached (22%). Of these 11 had clearly documented entry-site breaks or problems at the entry-site leading to vitreous traction and retinal detachment (45%). The average length of time to detachment from the initial surgery overall was 3 months and was 1 month on average for those eyes with entry-site breaks. 14 underwent subsequent surgery with placement of silicone oil, 5 eyes had scleral buckling procedures, and 5 eyes were inoperable. Conclusions: Entry-site breaks are a significant cause for recurrent retinal detachment. Entry-sites must be checked at the end of each vitrectomy as breaks may occur equally with routine detachment surgery as well as with more prolonged and complicated procedures Entry-site breaks are associated with several potential risk factors including bullous superior retinal detachments, manipulation in addition to vitrectomy, and factors leading to abnormal vitreous with potential vitreous adhesions.