Signal quality of biometry in silicone oil–filled eyes using partial coherence laser interferometry

Abstract

To assess the practical feasibility and signal quality of axial length measurements by partial coherence laser interferometry in silicone oil-filled eyes with previous complicated vitreoretinal surgery. Department of Ophthalmology, University Cologne, Cologne, Germany. Using a Zeiss IOLMaster, axial length measurements and signal-to-noise ratios of optical biometry in silicone oil-filled eyes (n=45) and contralateral eyes without tamponade (n=41) were analyzed. Axial length measurements with signal-to-noise ratio > or =2 were feasible in 41 of 45 silicone oil-filled eyes (91%) and 37 of 41 eyes without tamponade (90%). Cataract, central retinal detachment, vitreous hemorrhage, and emulsified oil droplets attached to the intraocular lens were reasons for failure of partial coherence laser interferometry. The signal-to-noise ratio of the first 2 measurements was significantly smaller (P=.04) in silicone-filled eyes (4.4 +/- 2.0) than in eyes without tamponade (5.5 +/- 3.0). Axial lengths of the oil-filled eye and the contralateral eye showed a significant intraindividual correlation (P<.0001, Spearman r=0.84). Partial coherence laser interferometry shows good clinical practicability in silicone oil-filled eyes with previous complicated vitreoretinal surgery. Further studies are needed to assess the reliability of these measurements with regard to postoperative refraction after combined oil removal and cataract surgery.