Adjustment of intraocular lens power for sulcus implantation.

摘要

In a recent letter, Spokes et al. suggested that intraocular lens (IOL) power needs to be increased when implanted in the ciliary sulcus, as opposed to the capsular bag, to achieve the same refractive result. As implied, this conclusion is counterintuitive and it is incorrect for the specific case of a zero power IOL, which would require no adjustment. This prompted us to analyze a multisurgeon set of data from Cheltenham General Hospital, United Kingdom. Patients who had had sutureless phacoemulsifica-tion and sulcus IOL implantation with or without automated anterior vitrectomy but without other procedures were identified in an electronic database (Medisoft, Ltd.). Eyes without partial coherence inter-ferometry biometry or postoperative subjective refraction or with corrected distance visual acuities worse than 6/12 or with more than 2.0 diopters (D) of postoperative astigmatism were excluded. The IOL power that would have predicted the actual postoperative refraction if implanted in the capsular bag was calculated for the Holladay 1 formula and for the SRK/T formula for each eye using optimized formula constants. The relationships between IOL power reduction and capsular bag IOL power and axial length (AL) (Figure 1) were determined by linear regression using R 2.10.1 statistical software (R Foundation for Statistical Computing).