ABSTRACT
PURPOSE: To analyze corneal thickness (CT) by anterior segment optical coherence tomography and ultrasound pachymetry in precut endothelial keratoplasty (EK) donor corneas at the eye bank. METHODS: Thirty-six corneas were analyzed. All corneas were dissected to create lamellar grafts for EK using the standard eye bank protocol. We measured central and peripheral (3 mm from center) CT by ultrasound after lamellar tissue processing and by optical coherence tomography after the tissue was transferred to a viewing chamber. We performed paired t tests and Pearson correlation analyses to compare ultrasound and optical coherence tomography measurements. RESULTS: Central CT measurements by optical coherence tomography versus ultrasound in donor corneas were not statistically different (mean: 169 vs. 177 µm, respectively, P = 0.09). There was a strong correlation between measurements of central CT (r = 0.73, P < 0.0001). There was a statistically significant difference in mean peripheral CT measurements by optical coherence tomography and ultrasound (mean: 190 vs. 236 µm, respectively, P < 0.0001); at peripheral locations, measurements correlated moderately (r = 0.52, P = 0.002). CONCLUSIONS: Optical coherence tomography measurements of EK-prepared tissue averaged 8 µm thinner than the ultrasound measurements, similar to clinical measurements of central CT. Given the growing interest in the effect of EK graft thickness on patient outcomes, it is important to understand the differences in measurements obtained by different devices used to assess donor corneas.
Subject(s)
Cornea/anatomy & histology , Corneal Pachymetry , Descemet Stripping Endothelial Keratoplasty , Tissue Donors , Tomography, Optical Coherence , Humans , Organ SizeABSTRACT
Diabetic retinopathy (DR) is the leading cause of new-onset blindness in working-age individuals in the USA and represents a growing worldwide epidemic. Classic risk factors for onset or progression of DR include poor glycemic control, hypertension and hyperlipidemia; however, these factors account for only a small proportion of the risk of DR. New systemic risk factors are emerging, which may allow for personalized risk profiling and targeted treatment by physicians. In addition, early studies of vitreous fluid in patients with DR have resulted in a new paradigm: diabetes causes inflammation in the retina, which is mediated by multiple small signaling molecules that induce angiogenesis and vascular permeability. Future treatment of DR may involve two approaches: early vitreous analysis, followed by drug treatment targeted to the unique vitreous composition of the patient; and collaboration between ophthalmologists and primary care providers to address the unique systemic risk profile of each diabetic patient.
ABSTRACT
Diabetic retinopathy is a progressive disease that results from vascular injury due to chronic hyperglycemia. It is the leading cause of blindness in working-age adults in the US and is usually asymptomatic until late stages. Treatment with laser photocoagulation is effective at preventing severe vision loss; thus, diabetic patients should be referred for regular screening by an ophthalmologist. New inhibitors of vascular endothelial growth factor may provide targeted nonsurgical treatment to improve vision in diabetic retinopathy.
