A 67 year-old male, of Jewish descent, came for an ophthalmological evaluation after a two-month history of blurry vision, as well as a desire to stop using eyeglasses in his everyday life. He does not refer any other relevant medical history.
At his initial assessment, uncorrected distance visual acuity (UDVA) was 20/20 in OD and 20/30 in OS. Uncorrected near visual acuity was J3. The initial refraction was -0.50DCx120º in OD and -1.75DS/-1.50DCx70º in OS. Corrected distance visual acuity (CDVA) was 20/20 for both eyes. Nuclear cataracts were observed in both eyes during slit lamp examination. The other anterior segment structures and fundus examination were unremarkable. The assessment for a surgical solution was initiated.
A corneal topography using the OPD Scan-III (Nidek Co., LTD. Gamagori, Japan) was performed in OS. SimK was 42.22@135º/ 41.45@45º. For IOL power calculation, an optical biometry using IOLMaster 500 (Carl Zeiss, Oberkochen, Germany) together with Barrett Universal II formula was used. The average calculation of lens power was +17.00D for OS.
After assessment, phacoemulsification surgery and IOL placement were done in OS, implanting a trifocal lens model AT LISA tri 839MP (Carl Zeiss, Oberkochen, Germany). The surgery was performed uneventfully.
During the first week of the postoperative period, the UDVA was 20/20 in OS. The refraction at this time was -1.25DCx120º.
Six months into the postoperative period, the patient noted persistent blurred vision and night glare appeared. Slit lamp examination was performed and cornea guttata was observed. A specular microscopy (Fig 1) with EM-3000 (Tomey, Phoenix, AZ, USA) and a corneal topography using OPD Scan- III were performed.
In OD, the specular microscopy (central) showed a central corneal thickness (CCT) of 535, cell density (CD) of 1716 cells/mm2, polymegathism of 53% and pleomorphism of 42%. In OS, the examination showed a CCT of 539, CD of 934 cells/mm2, polymegathism of 113% and pleomorphism of 24%. Both eyes had presence of guttae.
In OD, the OPD scan showed a SimK of 42.03@65º/41.82@155º. The Zernike analysis showed a total of 0.660, with 0.469 @139º of tilt. Meanwhile, in OS, SimK was 42.08@15º/41.56@105º and the Zernike analysis showed a total of 1.396, with 0.539@295º of tilt and 0.410 of high order aberrations (HOAs). A well-centered IOL was observed.
As visual symptoms didn’t improve over time, or with the spherocylindrical correction of residual error, a surgical option was preferred, and an IOL exchange was proposed. A second low-frequency optic interferometry with IOL Master 500 was performed, and using Barrett Universal II Formula, an average lens power of +18.00D was calculated. A monofocal aspheric IOL, the ZCB00 (Abbott Medical Optics Inc, Santa Ana, CA, USA), was favored.
During the first week after the IOL exchange, UDVA was 20/25. Refraction at this time was -0.50Ds/-0.50DCx 90º in OS. Postoperative period developed without complications.
Patient follow-up was given for two years. His last UDVA was 20/20 in both eyes and near visual acuity was J1. His last specular microscopy showed a CCT of 593, CD of 1332 cells/mm2, polymegathism of 64% and pleomorphism of 33% in OD; and a CCT of 546, CD of 1105 cells/mm2, polymegathism of 68% and pleomorphism of 26% in OS.