Koc, Hakan; Simsek, Meltem Hazel; Akkus, Mustafa

Purpose: To determine the structure and properties of corneal endothelial cells in patients with methamphetamine use disorder. Material and method: The cross-sectional study included 33 eyes of 33 patients with methamphetamine (meth) use disorder and 33 eyes of 33 healthy subjects. Mean cell density, coefficient of variation, hexagonality ratio, maximum cell area, normal cell area, minimum cell area, and mean cell area were evaluated by non-contact specular microscopy. The parameters recorded in each group were compared. Results: The mean ages of the individuals in the meth and control groups were 32.36 ± 7.68 and 31.18 ± 4.79 years, respectively. The mean daily meth dose was 0.306 ± 0.154 g, mean weekly meth use was 2.70 ± 1.46 days, and mean total meth dose was 302.70 ± 296.04 g in the meth group (p = 0.456). The mean corneal endothelial cell count (ECD) values were 2692.82 ± 372.52 in the Meth group and 2869.7 ± 261.31 in the control group (p = 0.76). The mean coefficient of variation (CV) values were 30.76 ± 3.41 in the meth group and 29.21 ± 2.55 in the control group (p = 0.042). Mean hexagonality ratio (%) (HEX) values were 57.73 ± 9.38 in the meth group and 57.88 ± 9.96 in the control group (p = 0.949). A positive correlation was observed between CV and meth dose and duration of meth use (p = 0.011, p = 0.000, respectively). Conclusion: The results of our study indicate that the corneal endothelium is subjected to stress in patients with a methamphetamine use disorder. The CV value suggests that the usability of methamphetamine as a quantitative indicator in the evaluation of possible corneal endothelial toxicity is an area that needs to be supported by further research.

Tasli, Nurdan Gamze; Gunay, Betul Onal; Ugurlu, Adem; Eren, Mehtap Arslanturk; Aykut, Murat; Esenülkü, Cenap Mahmut

Purpose: To investigate retinal thickness and vascular structure in patients with non-alcoholic fatty liver disease (NAFLD) using optical coherence tomography (OCT) and OCT angiography (OCTA) and to compare the results with healthy controls. Method: The medical records of NAFLD patients were retrospectively reviewed. Macular thickness (MT) and peripapillary retinal nerve fibre layer (pRNFL) thickness were assessed. The vessel density (VD) of Superficial Capillary Plexus (SCP), Deep Capillary Plexus (DCP), foveal avascular zone (FAZ) area, FAZ circularity index (CI), and FAZ perimeter were also recorded. Results: The study included 64 patients with NAFLD and 64 healthy controls. Mean MT and pRNFLT were similar between groups. The study group showed a significant reduction in VD-DCP compared to the control group (36.0 ± 5.2 vs. 38.5 ± 4.1, p < 0.001). Total FAZ area was greater in the study group than in the control group (0.42 ± 0.10 vs. 0.33 ± 0.12mm2, p < 0.001). FAZ CI also differed between groups (0.47 ± 0.08 vs. 0.53 ± 0.08, p < 0.001). Enlarged FAZ area and decreased VD-DCP were significantly associated with NAFLD severity. Conclusion: Individuals with NAFLD have certain changes in the retinal microvasculature, including reduced VD-DCP, an increased FAZ area, and a decreased of FAZ CI. The variations in VD-DCP and FAZ area exhibit discrepancies according to the disease grade. There are some limitations, including its retrospective nature, the small number of participants, the lack of analysis of the peripapillary area, and the lack of examination of longitudinal changes.

Taşll, Nurdan Gamze; Icel, Erel; Karakurt, Yücel; Ucak, Turgay; Ugurlu, Adem; Yilmaz, Hayati; Akbas, Emin Murat

Background: We aimed to compare the morphological characteristics of corneal endothelial cells in type 2 diabetic patients and age-matched healthy subjects by specular microscopy. We also aimed to determine the association of corneal morphological features with the general characteristics and laboratory data of diabetic patients, including disease duration, haemoglobin A1c (HbA1c) levels and urine albumin creatinine ratio. Methods: A total of 195 diabetic patients and 100 healthy controls were enrolled in the study. All participants underwent a complete ophthalmological examination. Corneal endothelial measurements were performed using a noncontact specular microscopy. Laboratory data including serum fasting glucose, haemoglobin A1c levels, creatinine levels, and the urinary albumin-to-creatinine ratio were recorded. Diabetic patients were further subdivided into 3 groups according to the presence and stage of diabetic retinopathy. Specular microscopy findings and central corneal thickness of all patients were compared. Results: The ECD and hexagonal cell ratio were significantly lower, while the average cell size, CV%, and central corneal thickness were determined to be significantly higher in diabetic patients than in healthy controls (p = 0.001). With the presence and advancement of diabetic retinopathy, the ECD and hexagonal cell ratio decreased, while the average cell size, CV%, and central corneal thickness increased. When correlation analysis was performed between corneal morphological features and laboratory data of diabetic patients, ECD showed a significant negative correlation with diabetes duration (p = 0.028). HbA1c levels, urinary albumin-creatinine ratio (p = 0.041), average cell size and CV showed a positive correlation with these parameters. Conclusion: In conclusion, keratopathy is an important complication of type 2 diabetes. With an increase in the stage of diabetic retinopathy, alterations in corneal findings also increased. In that respect, we can suggest that keratopathy should be evaluated more cautiously in diabetic patients.