Abstract
Abstract: :
Purpose: To compare clinical status of eyes before and after penetrating keratoplasty (PK) among patients in the CLEK study who underwent PK during follow–up Methods: During 7 years of follow–up in the CLEK study cohort of 1,209 patients, 166 eyes of 139 patients underwent PK. Patients with unilateral PK at baseline were excluded. Clinical outcomes of eyes that underwent a PK were compared at the annual visit prior to PK and first annual visit post PK. We report on pre– and post–PK status of scarring, staining, best correct visual acuity (BCA; high and low contrast), mean steep and flat keratometric readings (K), and contact lens comfort. McNemar's test was used to compare scarring and staining; matched–pair, non–directional t–tests were used to compare continuous variables. Results: The presence of corneal staining was statistically significantly lower post–PK (9.0%) compared to pre–PK (42.4%, n = 144 eyes, p = <0.0001). High contrast BCA (n = 69) was significantly improved post–PK (48.9 ± 10.7 letters correct) compared to pre–PK (36.4 ± 13.1, p = <0.0001). Low contrast BCA (n = 69) was also significantly improved post–PK (33.4 ± 13.7) compared to pre–PK (18.1 ± 13.9, p = <0.0001). Both mean steep and flat K were significantly lower post–PK compared to pre–PK (steep K: 47.7 ± 5.0 vs. 61.3 ± 5.9, n = 128, p = <0.001 and flat K: 43.0 ± 5.0 vs. 57.2 ± 7.5, n = 134, p = <0.0001). Among 26 patients who wore CL both pre– and post–PK, CL comfort did not differ significantly between post–PK and pre–PK (3.2 ± 1.3 vs. 3.4 ± 1.0, p = 0.59). A significantly lower percentage of eyes were classified as having scarring post–PK as compared to pre–PK (11.8% vs. 86.1%, n = 144, p = <0.0001) Conclusions: CLEK Study subjects who underwent a PK had significant improvements in their clinical outcomes following surgery.