Changes in visual acuity, axial length, and refraction after removal of intraocular silicone oil following retinal reattachment surgery in Chinese patients: An open-label, prospective study

• Published in: Current therapeutic research 2009-06, Vol.70 (3), p.221-227
• Main Authors: Yang, An-Huai, PhD, Jin, Wei, PhD, Xing, Yi-Qiao, PhD
• Format: Article
• Language: English
• Subjects: axial length; Biological and medical sciences; Internal Medicine; Medical Education; Medical sciences; Pharmacology. Drug treatments; refraction; silicone oil; viscosity
• ISSN: 0011-393X; 1879-0313
• DOI: 10.1016/j.curtheres.2009.06.002

Abstract Background : As a vitreous substitute for long-term tamponade, silicone oil is widely used in vitreoretinal surgery to treat retinal detachment with proliferative vitreoretinopathy and some internal reconstruction after globe trauma. Objectives : The aim of this study was to compare the changes in visual acuity, axial length, and refraction in eyes before and after removal of intraocular silicone oil of 2 different viscosities after retinal reattachment surgery. The difference in the final anatomic success (stable retinal reattachment) rate was also assessed. Methods : Patients with surgically reattached retinas were enrolled in this open-label, prospective, nonrandomized study. All patients underwent pars plana vitrecto-my, lensectomy, scleral buckling or encircling, and epiretinal membrane dissection; silicone oil was removed after stable retinal reattachment was achieved. Refraction, axial length, final visual acuity, and stable retinal reattachment were assessed ≤2 days prior to surgery (baseline) and ≤1 month after silicone oil removal. Refraction was measured using an autorefractometer, and axial length was measured using A-scan ultrasonography, while visual acuity was assessed using a standard Snellen chart. Results : Of the 96 eyes assessed for inclusion, 89 eyes of 89 Chinese patients (mean [SD] age, 36.8 [4.3] years) were included in the study. Forty-two eyes (47.2%) were filled with 3700-centistoke (cS) silicone oil and 47 (52.8%) were filled with 5000-cS silicone oil. The mean interval between instillation and removal of the silicone oil was similar between the 3700-cS and 5000-cS groups (5.37 vs 5.10 months, respectively). The mean changes in visual acuity from before surgery to after removal of the silicone oil in the 3700-cS and 5000-cS groups were not significantly different (13/100 vs 15/100). The mean increase in axial length was also not significantly different in the 3700-cS group compared with the 5000-cS group (11.92 [1.97] vs 12.33 [1.28] mm). Mean decrease in refraction was significantly lower in the 3700-cS group compared with the 5000-cS group (5.80 [1.51] vs 6.88 [2.31] diopters; t = 2.57, P < 0.05). The anatomic success rate was 92.9% (39/42 patients) in the 3700-cS group and 91.5% (43/47) in the 5000-cS group. Conclusions : A statistically significant decrease in refraction from baseline was found in the 3700-cS group compared with the 5000-cS group in these Chinese patients who underwent instillation and removal of si