Purpose: We performed a prospective clinical trial to evaluate computerized videokeratoscopic analysis of the peripheral recipient cornea in intraocular lens power calculations for triple procedures: penetrating keratoplasty, cataract extraction, and intraocular lens insertion.

Methods: Patients with Fuchs' dystrophy underwent consecutive triple procedures. Surgery was performed in 16 eyes by a single surgeon (O.N.S.) using a single technique. If videokeratoscopic analysis disclosed dioptric powers greater than 40 diopters in the circumference of the corneal map, the surgeon's average postoperative central corneal power of 46 diopters was used with the regression formula. If dioptric powers less than 40 diopters were detected in the circumference of the corneal map, 45 diopters was used to avoid postoperative hyperopic shifts and to decrease deviation from intended refractive error. Refraction and videokeratoscopic analysis were performed six months after suture removal (18 to 24 months postoperatively).

Results: Analysis of covariance demonstrated that preoperative peripheral videokeratoscopic data of the recipient cornea correlated (P = .0001) with postoperative central corneal power, whereas preoperative central corneal power of the recipient cornea did not correlate (P = .35). Deviation from intended refraction (range, -2.54 to +1.22 diopters) was within 2 diopters in 14 eyes (88%) and within 3 diopters in all eyes. No patients had anisometropia greater than 3 diopters.

Conclusion: Preoperative data from computerized videokeratoscopic analysis of the recipient peripheral cornea correlated with postoperative central corneal power, and improved postoperative refractive outcomes compared with previously reported results of triple procedures.

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http://dx.doi.org/10.1016/s0002-9394(14)71961-0DOI Listing

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