Posters

Brunescent cataract surgery in severe keratoconus: how to solve the problem of postoperative refractive error prediction?

Poster Details

First Author: M.Pomorska POLAND

Co Author(s):    M. Szalinski   M. Misiuk-Hojlo                 

Abstract Details

Purpose:

To evaluate the visual, refractive and topographic outcomes in patient with severe keartoconus and bilateral (OU) brunascent cataract who underwent cataract surgery and to analyze the causes of biometry prediction error (BPE). The alternative way of patient surgical management without primary intraocular lens (IOL) implantation is discussed.

Setting:

77-year old patient was referred to Ophthalmology Department of Wroclaw Medical University, Poland for cataract surgery in right and left eye (RE and LE). The patient complained of marked worsening of vision within last 6 months, she could no longer walk on her own.

Methods:

It was impossible to measure refraction and uncorrected visual acuity (VA) was 0,05 (Snellen) in RE and counting fingers at 1 meter in LE. Slit lamp examination revealed keratoconus OU and dense brunascent cataract OU. Automated keratometry and corneal topography were performed with similar K values results. The actual average K value of RE measured 58,15D and of LE 70,12 D. There was no fundal view OU due to dense cataracts and ultrasound imaging showed normal anatomy of posterior segment. Axial length of RE and LE recorded with contact ultrasound biometry was 26,77mm and 27,04mm, respectively.

Results:

We planned phacoemulsification in RE because of better visual prognosis. According to RE biometry using SRK-T formula and measured K values -13,0 D IOL was required to obtain -1,0 D post op refraction. Considering multifactorial causes of biometry error and possible need for keratoplasty in the future it was decided to perform phacoemulsification without IOL implantation, achieving patient consent for secondary procedure. At 1 month follow up after uneventful phacoemulsification manifest refraction was -7,75Dsph/-8,25Dcylx2 with uncorrected VA of 0,15 (Snellen). BPE would amount 5,07D of myopic shift. The patient is satisfied and asked for the same treatment in fellow eye.

Conclusions:

The eyes with severe keratoconus and cataract pose a challenge in terms of post op refraction prediction. There is no validated protocol for IOL power calculation and the choice of K values is left to the surgeon. Secondary IOL implantation may be an alternative way of management in cases with high risk of biometry prediction error. Sometimes less is enough for the patient.

Financial Disclosure:

NONE