Abstract
Purpose :
Corneal endothelial cell (CEC) loss after corneal transplantation is the leading cause of secondary graft failure, followed by immunological rejection. Intracellular dark endothelial spots (IDES), as imaged by specular microscopy, are observed in various conditions, such as post-keratoplasty, ICE syndrome, uveitis, and diabetes mellitus. This study aimed to investigate IDES incidence after penetrating keratoplasty (PK) and its relationship with decreased endothelial cell density (ECD), clinical factors, and preoperative aqueous humor (AqH) protein/cytokine levels.
Methods :
This study included 80 eyes (65±17 years) undergoing PK at Tokyo Dental College Ichikawa General Hospital between 2015 and 2017. IDES development and ECD after PK were determined based on specular microscopy images. Preoperative AqH cytokine levels (interleukin [IL]-1β, -6, -8, -10, MCP-1, P-selectin, sICAM-1, and interferon-γ) were measured using multiplex immunoassay. To identify clinical risk factors for IDES, we assessed clinical factors (age, sex, number of previous intraocular surgeries, presence of glaucoma, graft ECD, iris damage severity, and AqH protein/cytokine levels) and conducted logistic regression analysis.
Results :
IDES was observed in 40 eyes (50%) within 18 months after PK. ECD in eyes with IDES was significantly smaller compared with those without (1801±472 vs 1156±528 at 12 months, 1871±351 vs 1059±577 at 24 months, and 1734±850 vs 668±368 at 36 months, all P≤0.0001). A decrease in ECD by≥50% within 18 months after PK was observed in 28 eyes (70.0%) with IDES and 3 (9.7 %) in those without (Fisher test, P≤0.001). During the follow-up period after PK, secondary graft failure was observed in 10 eyes (25%) with IDES, whereas there was no graft failure in eyes without (P≤0.001). The preoperative AqH levels of IL-8 were significantly higher in eyes with IDES after PK compared with those without (P=0.04). Logistic regression analysis identified less graft ECD as a significant factor for IDES after PK (Z=-2.36, P=0.002). There were no significant differences in other clinical factors and AqH cytokine levels between the eyes with and without IDES.
Conclusions :
IDES can serve as a predictive marker for subsequent ECD decrease. A greater number of graft ECD can be a protective factor for IDES development and CEC loss following PK.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.