RESUMO
OBJECTIVE: To investigate the effects of silicone oil (SiO) on macular thickness (MT) and subfoveal choroidal thickness (SFCT) in patients with macula-off rhegmatogenous retinal detachment (RRD) undergoing pars plana vitrectomy (PPV). MATERIAL AND METHODS: In this prospective study, 70 eyes of 70 patients who received SiO tamponade for the treatment of macula-off RRD were treated with PPV and a 5000-cSt SiO endotamponade followed by subsequent SiO removal. MT and SFCT were measured 1 day before and 3 months after SiO removal using spectral-domain optical tomography (SD-OCT) and enhanced depth imaging optical tomography (EDI-OCT). The patients were divided into 3 groups according to the length of time that the SiO was present: group 1 (3-6 months), group 2 (6-9 months), and group 3 (9-18 months). RESULTS: A total of 70 eyes of 70 patients with a mean age of 57.22±9.83 years (range: 30 years to 75 years) were included in the SiO (5000-cSt) study. SiO was extracted after a mean duration of 8.67±5.33 months (range, 3-18 months) after PPV. In the 1st group, BCVA increased from 1.83±0.32 log MAR before PPV to 0.85±0.41 log MAR at 3 months after silicone removal (P<0.001). In the 2nd group, BCVA increased from 1.76±0.38 log MAR before PPV to 0.86±0.48 log MAR at 3 months after silicone removal (P<0.001). In the 3rd group, BCVA increased from 1.89±0.28 log MAR before PPV to 1.08±0.63 log MAR at 3 months after SiO removal (P=0.001). There was no statistically significant change in MT in the difference values of each group. As the length of SiO presence in the eye increased, significant thinning was observed on measurement of SFCT. Differences in the SFCT values were -14.91µm, -18.76µm, and -51.50µm in groups 1, 2, and 3 respectively (P=0.004). CONCLUSIONS: A significant decrease in macular and choroidal thicknesses after SiO removal was observed. Presence of SiO endotamponade for 9 months was associated with subfoveal choroidal thinning and decreased final visual acuity in eyes undergoing RRD surgery. SD-OCT and EDI-OCT may be recommended for the treatment and follow-up of patients with complications caused by the use of SiO tamponade.