Objective: To assess pre-operative conditions that could influence primary anatomical success rate in a cohort of patients with rhegmatogenous retinal detachments (RRD) treated with primary vitrectomy and no scleral buckling.Methods: A retrospective analysis was performed in a group of patients that underwent primary pars plana vitrectomy with gas tamponade and without scleral buckling for RRD between 2014 and 2019, with a minimum follow-up of 4 months.Results: 305 eyes of 301 patients were included; 59.01% eyes were phakic, 39.01% were pseudophakic and 1.96% aphakic. 13.11% of patients had proliferative vitreoretinopathy grade B and 3.28% proliferative vitreoretinopathy grade C at the time of diagnosis while 83.61% had proliferative vitreoretinopathy grade 0 or A. 53.1% had superior breaks, 15.4% inferior breaks and 31.5% a combination of both. Primary success rate was obtained in 90.82% of eyes (95%CI 87.58-94.06). 9.18% of eyes (95%CI 5.94-12.42) re-detached. In 3.27% the cause of re-detachment was proliferative vitreoretinopathy, and in the remaining 5.90% because of a new or a missed break, the leakage of a previously treated break, or an area of shallow peripheral detachment with no detectable break. Of 181 phakic eyes, 10.49% re-detached, whereas in over 126 aphakic or pseudophakic eyes 7.75% re-detached (p=0.42). 16.39% eyes of the entire cohort had preoperative grade B or C proliferative vitreoretinopathy, whereas 32.14% of re-detached eyes had preoperative grade B or C proliferative vitreoretinopathy p=0.02). Th eyes that redetached after the first surgery had a mean of 2.5 (95%CI 1.86-3.13) retinal tears, against a mean of 1.87 (95%CI 1.73-2.00) retinal tears of those that did not re-detach after the first surgery (p=0.02).
Conclusion:We found location of breaks and lens status to be independent factors not related to a lower single operation success rate, whereas the number or size of breaks and preoperative proliferative vitreoretinopathy stages B or C were independent factors related to a higher likelihood of re-detachment.