Use of Heavy Silicon Oil as Intraocular Tamponade for Inferior Retinal Detachment Complicated by Proliferative Vitreoretinopathy: A Multicentric Experience.

INTRODUCTION: This is a multicentric study on the use of heavy silicon oil (HSO) as an intraocular tamponade for inferior retinal detachment (RD) complicated by proliferative vitreoretinopathy (PVR). METHODS: 139 eyes treated for RD with PVR were included in the study. 10 (7.2%) were affected by primary RD with inferior PVR, while 129 (92.8%) were affected by recurrent RD with inferior PVR. 102 eyes (73.9%) had received a silicon oil (SO) tamponade in a previous intervention prior to receiving HSO. Mean follow-up was 36.5 (standard deviation = 32.3) months. RESULTS: The median interval between HSO injection and removal was 4 months (interquartile range: 3). At the time of HSO removal, the retina was attached in 120 eyes (87.6%), whereas in 17 eyes (12.4%), it had re-detached while the HSO was in situ. 32 eyes (23.2%) showed recurrent RD. A subsequent RD relapse was observed in 14.2% of cases with no RD at the time of HSO removal, and in 88.2% if an RD was present at the time of HSO removal. Advancing age showed a positive association with retinal attachment at the end of follow-up, while the risk of RD relapse at the end of the follow-up showed a significant negative association with HSO tamponade duration and with the use of SO rather than air or gas as post-HSO tamponade materials. Mean best corrected visual acuity was 1.1 logarithm of minimum angle of resolution at all follow-up time points. 56 cases (40.3%) needed treatment for elevated intraocular pressure (IOP), with which no clinically relevant variables were associated during follow-up. CONCLUSION: HSO represents a safe and effective tamponade in cases of inferior RD with PVR. The presence of RD at the time of HSO removal is a negative prognostic factor for the development of a subsequent RD relapse. According to our findings, in cases of RD at the time of HSO removal, a short-term tamponade should definitely be avoided, in favor of SO. Special attention must be paid to the risk of IOP elevation, and patients should be closely monitored.

Microstructural Macular Changes after Pars Plana Vitrectomy for Primary Rhegmatogenous Retinal Detachment.

PURPOSE: This study aimed to describe foveal microstructural changes after pars plana vitrectomy (PPV) with air tamponade for rhegmatogenous retinal detachment (RRD). METHODS: External limiting membrane (ELM) and ellipsoid zone (EZ) integrity, cystoid macular edema (CME), and subretinal fluid bleb (SB) development were analyzed using optical coherence tomography in 59 eyes over a 6-month follow-up period after PPV surgery for RRD. Eyes were grouped as macula-on (n = 30) or macula-off (n = 29), and the association between ELM and EZ recovery and best-corrected visual acuity (BCVA) was investigated. Predictive factors for ELM and EZ recovery were also identified. RESULTS: The interval between symptom onset and surgery did not significantly differ between the macula-on and macula-off groups. Macula-on patients showed ELM and EZ integrity throughout, whereas macula-off patients had ELM and EZ integrity restored in 89.7% and 86.2% cases, respectively, with a resultant increase in final BCVA. Significant associations were found between preoperative macular involvement and ELM/EZ restoration. ELM/EZ recovery was also inversely associated with CME development. Significant associations were also found between final BCVA and preoperative BCVA and EZ recovery. CME and SB development were equally distributed between the 2 groups. CONCLUSION: Prompt surgery for macula-off RRD allows the progressive recovery of outer retinal layers and significant visual gain.

Vitreous substitutes: the present and the future.

Vitreoretinal surgery has advanced in numerous directions during recent years. The removal of the vitreous body is one of the main characteristics of this surgical procedure. Several molecules have been tested in the past to fill the vitreous cavity and to mimic its functions. We here review the currently available vitreous substitutes, focusing on their molecular properties and functions, together with their adverse effects. Afterwards we describe the characteristics of the ideal vitreous substitute. The challenges facing every ophthalmology researcher are to reach a long-term intraocular permanence of vitreous substitute with total inertness of the molecule injected and the control of inflammatory reactions. We report new polymers with gelification characteristics and smart hydrogels representing the future of vitreoretinal surgery. Finally, we describe the current studies on vitreous regeneration and cell cultures to create new intraocular gels with optimal biocompatibility and rheological properties.