Corneal Endothelial Outcomes in Diabetic Patients Following Repeated Anterior Chamber Paracentesis

PURPOSE: The aim of this study was to evaluate longitudinal changes in corneal endothelial morphology following serial anterior chamber (AC) paracentesis in patients with type 2 diabetes mellitus. METHODS: This is a prospective cohort study with both cross-sectional and longitudinal components. Participants with type 2 diabetes mellitus underwent bilateral AC paracentesis, specular microscopy analysis, and dilated fundus examination at baseline and at four-month intervals over 3 years. Endothelial parameters included cell density (CD), coefficient of variation, hexagonality, and central corneal thickness. Linear mixed-effects models were adjusted for age, sex, laterality, hemoglobin A1c, diabetes duration, diabetic retinopathy severity, and lens status. RESULTS: One hundred twelve participants were included at baseline [median age 63 years, 50% female, median hemoglobin A1c 7.8% (interquartile range 1.93), median diabetes duration 20 years]. Most had mild-to-moderate nonproliferative DR (60%), and 30% were pseudophakic. At baseline, pseudophakic lens status (mean ± SD CD: 2566.7 ± 190.8 cells/mm2) predicts a lower CD of -161 cells/mm2 (95% confidence interval -243.1 to -83.1) compared with phakic eyes (2721.5 ± 184.1 cells/mm2). Pseudophakia also predicts a higher coefficient of variation of +3.7 (95% confidence interval, 0.2-7.0). These differences persisted longitudinally. Repeated AC paracentesis was not associated with any significant change in any parameters. CONCLUSIONS: To our knowledge, this is the largest and longest prospective evaluation of repeated AC paracentesis in humans with diabetes. Despite up to 10 AC paracenteses per eye over 3 years, no adverse effects on endothelial cell morphology were observed. These findings support the broader adoption of serial aqueous sampling as a precision-medicine tool in ophthalmology and research.