To evaluate changes in ACA induced by pars plana vitrectomy with SO 1000cs injection in vitreo-retinal surgery in phakic eyes using AS-OCT and changes in the IOP preoperatively, post-operatively and post-silicone oil evacuation.

Abstract Introduction Ocular hypertension and secondary glaucoma are relatively common and serious complications in silicone filled eyes which may end in blindness. Reports have described the percentage of incidence to be within 3 - 30 % of silicon filled eye which are complicated with secondary glaucoma. [1] Aim of study Evaluation of changes in anterior chamber angle and intra-ocular pressure (IOP) in patients with rhegmatogenous retinal detachment (RRD) who underwent pars plana vitrectomy (PPV) with silicone oil (SO) 1000cs tamponade and after silicone oil evacuation.

Population The study was a prospective interventional study. The study included 30 eyes from 30 patients with rhegmatogenous retinal detachment (RRD) who are going to undergo PPV with SO injection. The study was conducted at Ophthalmology department, Minia University Hospital in Egypt between April 2023 and April 2024.

Inclusion Criteria:

• • Patients with rhegmatogenous retinal detachment who are going to undergo vitreoretinal surgery with silicone oil 1000cs injection as tamponade

Exclusion Criteria:

• Patients with history of intraocular surgery, laser therapy or intravitreal injection.
• Patients with significant corneal opacity.
• Patients with ocular diseases as retinal vein occlusion, uveitis and proliferative diabetic retinopathy.
• Patients with preexisting glaucoma or family history of glaucoma.
• Patients with nystagmus.
• Patient with tractional retinal detachment, exudative retinal detachment or intraocular foreign body.
• Patients with anterior chamber abnormalities including posterior synechia, peripheral anterior synechia, hyphaema and iris abnormalities.
• Patients with severe proliferative vitreoretinopathy grade C or more.

Patients who are phakic with rhegmatogenous retinal detachment