Corneal Endothelial Cell Density in Uveal Coloboma Associated With Microcornea

Characteristics of Corneal Endothelium in Axenfeld Rieger Spectrum

PURPOSE

The purpose of this study was to compare the corneal endothelial characteristics in Axenfeld anomaly (AXA), Rieger anomaly (RGA), and Axenfeld-Rieger anomaly/syndrome with age-matched healthy controls.

METHODS

This is a retrospective, comparative case-control study of 52 eyes of 30 patients with AXA/RGA and AXA/S and 36 controls.

RESULTS

Median age at endothelial imaging was 21.5 years (interquartile range, 13.8-33.3 years). In the study group, the mean endothelial cell density (ECD) was 2112.4 ± 78.5 cells/mm 2 , the mean cell area (MCA) was 526.9 ± 28.5 μm 2 , and the coefficient of variation of cell size was 41.2 ± 1.8%. The ECD was significantly (all, P < 0.0001) lower than controls, while MCA ( P < 0.0001), SD of cell size ( P < 0.0001), and maximum cell area ( P = 0.0007) were significantly higher than controls. Four eyes of 3 patients had guttae on slitlamp evaluation and endothelial imaging. There were no differences in the corneal endothelial characteristics among the clinical subtypes.

CONCLUSIONS

Patients with AXA, RGA, and Axenfeld-Rieger anomaly/syndrome have lower ECD and increased MCA compared with normal eyes. The reduced ECD associated with inherent anterior segment alterations can predispose to the risk of postcataract surgery endothelial decompensation in these eyes. The association of guttae in some eyes needs further investigational studies.

Corneal Biometric Parameters and Refractive Properties in Microcornea With Normal Axial Length

PURPOSE

The purpose of this study was to evaluate the features of and relationships among corneal diameter, central corneal thickness (CCT), endothelial cell density (ECD), and corneal refractive properties in cases of microcornea (MC) with normal axial length.

METHODS

We included 22 patients (35 eyes) with MC and cataracts and 41 patients (48 eyes) with isolated cataracts as age-matched controls. They were divided into patients with MC younger than 18 years (MC-child), patients with MC 18 years or older (MC-adult), children with congenital cataracts (CCs), and adults with senile cataracts (SCs). Corneal diameter, axial and anterior chamber length, and keratometry were measured; central corneal endothelial cell imaging was performed.

RESULTS

The mean horizontal corneal diameter was 7.71 ± 1.51 and 8.78 ± 0.52 mm in MC-child and MC-adult groups, respectively, and 11.89 ± 0.59 and 11.52 ± 2.42 mm in child and adult controls, respectively. The mean CCT was 641.26 ± 63.37 (MC-child) and 617.38 ± 45.40 mm (MC-adult), and 554.92 ± 34.64 (CC) and 551.58 ± 28.47 mm (SC). The mean ECD was 2898.47 ± 443.90 (MC-child) and 2825.81 ± 484.65 cells/mm 2 (MC-adult), and 3155.13 ± 372.67 (CC) and 2749.33 ± 399.63 cells/mm 2 (SC). The average keratometry was 44.22 ± 3.14 D (MC-child) and 43.86 ± 2.59 D (MC-adult), and 44.19 ± 1.44 D (CC) and 43.94 ± 1.34 D (SC).

CONCLUSIONS

Patients with MC and normal axial length possess specific parameters, including significantly smaller corneal diameter and thicker CCT than the patients in the control groups. There were no significant differences in ECD and average keratometry. These parameters should be taken into account in the follow-up and treatment.

Specular microscopy in clinical practice

Specular microscopy is a noninvasive diagnostic tool that allows for in vivo evaluation of corneal endothelium in health and various diseased states. Endothelial imaging helps in the diagnosis and management of several endothelial disorders. The review focuses on the principles of specular microscopy, limitations of endothelial imaging, and its interpretation in common conditions seen in the clinical practice. A thorough PubMed search was done using the keywords specular microscopy, corneal endothelium, and endothelial imaging.