To investigate the incidence of cystoid macular edema in eyes with primary rhegmatogenous retinal detachment successfully treated with vitrectomy with gas tamponade, and to evaluate the clinical variables associated with its development.

this is an observational, retrospective, multicentre study. The study is based on the retrospective collection of clinical data from patients undergoing gas tamponade vitrectomy for rhegmatogenous retinal detachment. The collection of such data by the investigators will take place at each participating center anonymously.

demographics, systemic, and preoperative, intraoperative and post-operative data will be collected The sample size was calculated to obtain approximately 200 patients with cystoid macular edema. Since cystoid macular edema has been detected in 13% of patients after retinal detachment gas vitrectomy, and assuming that this event can occur between 10% and 15% of cases, the study will include at least 2000 cases.

Inclusion Criteria:

• primary rhegmatogenous retinal detachment treated with vitrectomy with gas tamponade;
• follow-up of 3 months or more;
• age > 18 years ;
• no previous eye surgery, except cataract surgery performed at least 6 months after hospitalization for retinal detachment;
• anatomical success, i.e. retinal re-attachment, after a single gas vitrectomy;
• no other eye surgery during follow-up;
• availability of optical coherence tomography (OCT) imaging

Exclusion Criteria:

• history of other eye diseases (glaucoma, age-related macular degeneration, uveitis, diabetic retinopathy, maculopathy);
• macular hole;
• recurrent retinal detachment;
• use of silicone oil is used as a tamponading agent

consecutive patients with primary regmatogenous retinal detechment successfully treated by vitrectomy with gas tamnponade at several Eye Centers, will be included in the study.

clinical data will be retrospectively retrieved.