cornea

An analysis of factors influencing quality of vision after big-bubble deep anterior lamellar keratoplasty in keratoconus.

Am J Ophthalmol. 2015 Nov 14. pii: S0002-9394(15)00706-0. doi: 10.1016/j.ajo.2015.11.018. [Epub ahead of print]

An analysis of factors influencing quality of vision after big-bubble deep anterior lamellar keratoplasty in keratoconus.

Abstract

PURPOSE:

To identify causes of reduced visual acuity and contrast sensitivity after big-bubble deep anterior lamellar keratoplasty (DALK) in keratoconus.

DESIGN:

Prospective interventional case series.

METHODS:

This study included 36 eyes in 36 patients with keratoconus who underwent DALK using the big-bubble technique. A bare Descemet membrane was achieved in all cases. Univariate analyses and multiple linear regression were used to investigate recipient-, donor-, and postoperative-related variables capable of influencing the postoperative quality of vision, including best-spectacle corrected visual acuity (BSCVA) and contrast sensitivity.

RESULTS:

The mean patient age was 27.7±6.9 years old, and the patients were followed for 24.6±15.1 months postoperatively. The mean postoperative BSCVA was 0.17±0.09 LogMAR. Postoperative BSCVA ≥ 20/25 was achieved in 14 eyes (38.9%), whereas a BSCVA of 20/30, 20/40, or 20/50 was observed in 15 eyes (41.7%), six eyes (16.6%), and one eye (2.8%), respectively. Preoperative vitreous length was significantly associated with postoperative BSCVA (β=0.02, P=0.03). Donor-recipient interface reflectivity significantly influenced scotopic (β=-0.002, P=0.04) and photopic (β=-0.003, P=0.02) contrast sensitivity. The root mean square of tetrafoil was significantly negatively associated with scotopic (β=-0.25, P=0.01) and photopic (β=-0.23, P=0.04) contrast sensitivity. Recipient age, keratoconus severity, donor-related variables, recipient trephination size, and graft and recipient bed thickness were not significantly associated with postoperative visual acuity or contrast sensitivity.

CONCLUSION:

Large vitreous length, higher-order aberrations, and surgical interface haze may contribute to poor visual outcomes after big-bubble DALK in keratoconus.

RESULTS:

The mean patient age was 27.7±6.9 years old, and the patients were followed for 24.6±15.1 months postoperatively. The mean postoperative BSCVA was 0.17±0.09 LogMAR. Postoperative BSCVA ≥ 20/25 was achieved in 14 eyes (38.9%), whereas a BSCVA of 20/30, 20/40, or 20/50 was observed in 15 eyes (41.7%), six eyes (16.6%), and one eye (2.8%), respectively. Preoperative vitreous length was significantly associated with postoperative BSCVA (β=0.02, P=0.03). Donor-recipient interface reflectivity significantly influenced scotopic (β=-0.002, P=0.04) and photopic (β=-0.003, P=0.02) contrast sensitivity. The root mean square of tetrafoil was significantly negatively associated with scotopic (β=-0.25, P=0.01) and photopic (β=-0.23, P=0.04) contrast sensitivity. Recipient age, keratoconus severity, donor-related variables, recipient trephination size, and graft and recipient bed thickness were not significantly associated with postoperative visual acuity or contrast sensitivity.

CONCLUSION:

Large vitreous length, higher-order aberrations, and surgical interface haze may contribute to poor visual outcomes after big-bubble DALK in keratoconus.

Copyright © 2015 Elsevier Inc. All rights reserved.