Purpose: To study the application of intraoperative retinoscopy for intraocular lens (IOL) power calculation in combined cataract extraction and silicone oil removal.
Settings: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Methods: This study comprised patients with silicone oil-filled eyes and visually significant cataract who had combined cataract extraction by phacoemulsification and silicone oil removal by a standard method through the pars plana route. Retinoscopy was performed with a streak retinoscope, standard vertex distance of 13.0 mm, and distance of 50.0 cm. All eyes had in-the-bag implantation of a foldable IOL with an A-constant of 118.4. The IOL power was calculated using the Ianchulev formula as follows: R x 2.01449. Postoperative refraction was performed at 3 months, and the spherical equivalent was calculated.
Results: Twelve eyes of 12 patients were evaluated. The mean emmetropic power calculated by intraoperative retinoscopy was 20.46 diopters (D) +/- 3.4 (SD) (range 13.09 to 25.18 D) and the mean refractive error, -0.45 +/- 0.63 D (range -1.00 to +1.00 D). The postoperative refractive error was within +/-0.50 D in 4 eyes (33.3%) and within +/-1.00 D in all eyes. Ten eyes (83.33%) had a postoperative refractive error in the range of 0.00 to -1.00 D using IOL power based on intraoperative retinoscopy.
Conclusion: Intraoperative retinoscopy for IOL power calculation in combined cataract extraction and silicone oil removal gave satisfactory refractive outcomes, although further studies with more patients are required to confirm its usefulness and determine whether there are disadvantages.