Assessment of retinal structural and functional changes in silicone oil filled eyes

Abstract

Since its introduction by Cibis et al. in 1962, vitreous replacement by silicone oil has become an increasingly accepted treatment for severe and complicated retinal detachment. Silicone oil was introduced into the eye to serve as an eyeball stabilizer.

Numerous early laboratory studies indicated that the eye tolerated silicone oil well but the tolerance of various eye tissues to the oil is, however, a matter of ongoing controversy.

Cataract, glaucoma, and keratopathy can be major anterior segment problems after silicone oil injection. Of more importance potentially was the suggestion that silicone oil induces retinopathy.

The aim of this study was to evaluate the retinal functional and structural changes in silicone oil filled eyes in successful cases of pars plana vitrectomy with silicone oil tamponade.

After obtaining approval of research ethical committee and patients’ written informed consents, the current study was conducted on 15 adult patients who were presented to ophthalmology outpatient clinic of Ain shams university hospitals with rhegmatogenous RD and and underwent successful retinal detachment repair with pars plana vitrectomy and silicone oil tamponade.

Patients with rhegmatogenous RD with recent history of drop of vision (two weeks or less) were included in the current study while patients with previous retinal disease as diabetic retinopathy, retinal vein or artery occlusion, previous retinal surgery, Preexisting glaucoma, severe PVR (grade C) and those who developed silicone oil complications postoperatively as keratopathy, cataract and elevated IOP were excluded.

Ophthamological examination was done Preoperatively , 1 month postoperatively and after silicone oil removal (3 months postoperatively) which included:

• Best corrected visual acuity. • Contrast sensitivity. • Slit lamp examination. • Intraocular pressure . • Visual field examination . • Fundus examination . • OCT imaging (spectral domain) . • Electrophysiological studies (ERG, VEP). And as we analyzed the results of the current study showed that :

♦ The main risk factor for rhegmatogenous RD in the patients of the current study were high myopia.

♦ The patients ophthalmological examination revealed that

▪ BCVA:

Preoperative BCVA was significantly worse than sound eye, then after silicone oil filling and after silicone oil removal significantly improved but still significantly worse than sound eye (with no significant difference between filling and removal).