RESUMO
PURPOSE: To assess the accuracy of intraocular lens (IOL) power formulas, namely, SRK/T, Haigis, Barrett Universal II, Barrett True-K for keratoconus, Kane formula, and Kane formula for keratoconus, for cataract with keratoconus in Japanese eyes. SETTING: Five surgical sites in Japan. DESIGN: A retrospective case series. METHODS: Eyes with keratoconus undergoing cataract surgery were included. Postoperative refraction was compared with the prediction by the formulas. Visual acuity, manifest spherical equivalent, prediction error (PE), and mean absolute errors (MAEs) were determined 1 month postoperatively. The PE within 0.50 diopter (D), 1.00 D, and 2.00 D were compared between IOL formulas. Subgroup analysis based on the steepest keratometry (stage 1, ≤ 48 D; stage 2, > 48 D and ≤ 53 D; and stage 3, > 53 D) was performed. The relationship between PE and preoperative biometric data were assessed. RESULTS: Fifty eyes were included. The MAE of the Barrett True-K for keratoconus, Kane keratoconus, and Kane formulas were significantly lower than that of Haigis. A statistically significant difference in the prediction accuracy within ± 0.50 D was found between Kane keratoconus and Haigis. The prediction accuracy of the Barrett True-K for keratoconus, SRK/T, and Kane within ± 1.00 D was statistically significant compared with that of Haigis. In stage 3, the Barrett True-K for keratoconus had a significantly lower MAE than SRK/T and Haigis. CONCLUSION: Keratoconus-specific formulas were more accurate than existing formulas in Japanese eyes. The Barrett True-K formula for keratoconus had higher prediction accuracy in severe keratoconus.
RESUMO
PURPOSE: To report the usefulness of a new surgical method using intraoperative optical coherence tomography that can more accurately place the buckling material for scleral buckling using a noncontact wide-angle viewing system with a cannula-based chandelier endoilluminator for the treatment of rhegmatogenous retinal detachment. METHODS: The medical records of 12 eyes of 11 patients with rhegmatogenous retinal detachment treated with scleral buckling combined with real-time intraoperative optical coherence tomography observation were retrospectively reviewed. RESULTS: Real-time observations of the positional relationship between the protrusion of buckling material and retinal breaks with intraoperative optical coherence tomography revealed that retinal breaks were not properly placed on the protrusion of the buckling material in five eyes, requiring the intraoperative repositioning of the buckling material. Eventually, the scleral buckling combined with real-time intraoperative optical coherence tomography observation yielded the initial anatomical success rates of 100% without noteworthy intraoperative or postoperative complications. CONCLUSION: This procedure is a novel approach that enables safer and more accurate placement of the buckling material and may contribute to improving the outcomes of scleral buckling in the future.
