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Refractive outcomes of a single-step and a two-step approach for silicone oil removal and cataract surgery
V G Madanagopalan1, Pradeep Susvar1, M Arthi2
1Shri Bhagwan Mahavir Vitreo Retinal Services, Sankara Nethralaya, Chennai, India.
Purpose:
To compare the intermediate-term refractive outcomes of a single-step and a two-step approach for silicone oil removal (SOR) and cataract surgery.
Methods:
Case records of patients who had SOR and phacoemulsification (PE) from 2011 to 2013 at a tertiary center in South India were retrospectively analyzed. A total of 135 eyes that underwent ultrasound biometry (UB) were studied. Eighty-seven eyes had SOR and PE at a single surgery (Group A), where as UB was done in a silicone oil (SO) filled eye. Forty-eight eyes had SOR followed by PE later (Group B), where UB was done in a fluid-filled eye. The refractive error (RE) and best-corrected visual acuity (BCVA) at postoperative day 45 (D45) and postoperative month 3 (M3) were compared.
Results:
Baseline axial length, intraocular lens (IOL) power, and RE in both groups were comparable. A myopic shift (4.18 ± 5.47 diopters [D]) was noted in 92% eyes at M3. Forty-nine percent eyes had a RE of ≤±1.5D at M3. RE at D45 and at M3 was significantly lesser in Group B (-1.73 ± 2.04 vs. -0.64 ± 1.75; P, 0.002). BCVA was significantly lesser in Group A at baseline, at D45, and at M3 (P < 0.01 for all). There was no difference in other baseline characteristics of eyes that had RE ≤±1.5D and those that had RE >±1.5D at M3.
Conclusion:
SO-filled eyes had a myopic shift in refraction after SOR and PE. When UB is used for IOL power calculation, better refractive outcomes are obtained when SOR and PE are performed in a two-step approach.
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