Assessment of Visual Acuity after a year of penetrating Keratoplasty

Abstract

Purpose: To assess the best corrected visual acuity & post operative refractive errors after penetrating keratoplasty. Study design: Case series. Methods: This study included 45 patients undergoing penetrating keratoplasty for all indications of corneal blindness. Their pre-operative & post-operative best corrected visual acuity & post operative refractive errors were analyzed. All patients were operated by the same surgeon inSardarTrustEyeHospital, Garhi Shahoo & Institute of ophthalmology Mayo Hospital Lahore, Pakistan. The duration of follow-up was 1year. Results: The success rate of penetrating keratoplasty after 1- year follow up was 62%. Out of 45 patients, majority of patients (53%) had pre-operative VA between <3/60 to HM and rest of 38%, 2% & 7% patients had per-operative VA between PL, <6/60-3/60 & <6/18-6/60 respectively. Majority of patients (51%) have achieved post-operative uncorrected VA between <6/18 – 6/60. Out of 28 successful penetrating keratoplasty patients, 79% have achieved BCVA between 6/6 – 6/12 & 21% have between 6/18 – 6/60. Mean keratometric astigmatism was -4.45 ± 2.32 D & Mean cylindrical correction was -2.86 ±1.49 D.  Post-operative refractive errors were myopia (14%), hyperopia (4%), simple myopic astigmatism (7%), compound myopic astigmatism (21%) & mixed astigmatism (54%). Conclusions: Successful restoration of visual acuity after Penetrating Keratoplasty depends upon pre-operative clinical factors like causes of corneal blindness, ocular surface problems, corneal vascularization and previous history of graft complication. BestCorrectedVA achieved after Penetrating Keratoplasty ranged between 6/6-6/12 & majority of patient have Mixed Astigmatism. Key words: penetrating keratoplasty, corneal blindness, corneal graft survival, refractive errors, Visual acuity.