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Purpose: The purpose of this article was to study the impact of instillation of 1% fluorescein and mydriatics on measurements made by Scheimpflug imaging., Methods: This was a cross-sectional study of patients who had measurements of corneal shape (maximum keratometry and best fit sphere of anterior and posterior corneal surfaces), pachymetry (at the pupil center, corneal apex, and thinnest location), and anterior chamber parameters (depth, volume, and angle of anterior chamber and corneal volume) using the Pentacam HR before and after the instillation of fluorescein and mydriatics. Group A had baseline measurements that were repeated 1.5 hours after the instillation of 1% fluorescein and 0.8% tropicamide+ 5% phenylephrine eye drops. Group B had baseline measurements that were repeated 10 minutes after the instillation of 1% fluorescein, and group C had baseline measurements that were repeated 1.5 hours after the instillation of mydriatics., Results: Overall, 131 eyes of 131 patients were studied: 87 in group A, 28 in group B, and 16 in group C. Significant differences and wide variations were noted in corneal pachymetry and anterior chamber parameters in all 3 groups. The highest magnitude and range of difference was observed in pachymetry at the pupil center (17 ± 53.5 μm) and in anterior chamber volume (26.7 ± 69.8 mm 3 ). Corneal shape measurements of anterior and posterior corneal surfaces were not significantly affected by either fluorescein or mydriatics. Pupillary dilation also affected the ability of the Pentacam to accurately trace the pupil margin in 19.5% of cases., Conclusions: For consistent and accurate measurements, it is important that Scheimpflug imaging be performed before other tests which may need the instillation of fluorescein or mydriatics., Competing Interests: M. W. Belin and R. Ambrósio are consultants for Oculus Optikgeräte GmbH, Wetzlar, Germany. The remaining authors have no funding or conflicts of interest to disclose., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: To study the corneal endothelial cell density and morphological features in type 2 diabetic patients (cases) and compare it with nondiabetic subjects (controls) in a population-based cross-sectional study., Methods: Patients were recruited from the Sankara Nethralaya--Diabetic Retinopathy Epidemiology and Molecular Genetic Study, a population-based study to estimate the prevalence of type 2 diabetes and diabetic retinopathy in urban Chennai, South India. Corneal endothelial morphological features were recorded in all subjects using noncontact specular microscopy and central corneal thickness was measured using ultrasound pachymeter., Results: A total of 1191 cases and 121 controls were enrolled into the study. The mean corneal endothelial cell density (cells/mm(2)) was lower in cases than in controls (2550 ± 326 vs. 2634 ± 256; P = 0.001). No difference was observed in the mean pachymetry values, hexagonality %, and coefficient of variation of cell size between cases and controls. Multivariate regression analysis, after adjusting for age, showed the mean cell density to be lesser by 66 cells/mm(2) (95% confidence interval, 6.3-125.9) among diabetic patients compared with nondiabetic subjects., Conclusions: The results of this study, from a large population-based sample, support the earlier theories of lower endothelial cell counts among subjects with type 2 diabetes mellitus in comparison with nondiabetic controls.

Purpose: To report the unusual occurrence of bilateral, superficial, corneal fibrosis with pannus formation in a young woman with homocystinuria, and to describe the light and transmission electron microscopic findings of these deposits., Methods: Excision of the corneal lesion and amniotic membrane transplantation was performed in both eyes. The excised material was studied using light and transmission electron microscopy., Results: Whitish, elevated, irregular masses with superficial vascularization in the peripheral cornea were noted in both eyes. Histopathologic evaluation of the excised corneal tissue revealed variable epithelial thickness with melanin pigment in the basal layer. A fibrovascular pannus, fibrosis and disruption of the Bowman's layer, and fibrosis of anterior stroma were evident. Transmission electron microscopy revealed numerous empty intracytoplasmic vacuoles in the corneal epithelial cells and intracytoplasmic inclusions containing fibrillogranular material in the cytoplasm of keratocytes., Conclusion: We report the unusual association of corneal fibrosis and scarring in a young woman with homocystinuria. The deposits revealed the presence of membrane-bound inclusions containing fibrillogranular material in the corneal epithelium and keratocytes. Although the etiology of these deposits is not clear, the condition improved following excision of these lesions and amniotic membrane transplantation.

Purpose: To report the occurrence of bilateral macular hemorrhage following the use of azathioprine for immunosuppression in a corneal transplant recipient., Methods: The patient underwent therapeutic penetrating keratoplasty for progressive fungal keratitis in his left eye. Although the infection did not recur, the graft failed with vascularization of the cornea in three quadrants. He underwent repeat penetrating keratoplasty 2 years later and was treated with azathioprine (100 mg daily) to enhance graft survival. Four months after instituting azathioprine therapy, he developed aplastic anemia and macular hemorrhage in both eyes., Results: Fluorescein angiography revealed a preretinal location of the macular hemorrhage. After cessation of azathioprine therapy and treatment with blood component replacement, hematological parameters improved and the macular hemorrhage cleared with good visual recovery during the next 2 months., Conclusion: This report highlights the serious ocular and systemic complications that can occur following the use of systemic immunosuppressants after ophthalmic surgery.