Evaluation of the corneal thickness and endothelial changes following uncomplicated phacoemulsification in diabetic and non-diabetic patients with pseudo-exfoliation syndrome by specular microscopy.

PURPOSE: To evaluate corneal endothelial cell changes following uncomplicated phacoemulsification in diabetic patients with PEX, compared with diabetic patients and non-diabetic patients with PEX. METHODS: This prospective, comparative, non-randomized cohort study included 61 eyes of 61 patients who were diagnosed as having senile cataract. Patients were divided into three groups: Group (1) included 19 eyes of patients with DM and PEX, group (2) included 22 eyes of diabetic patients, and group (3) included 20 eyes of patients with PEX. All included patients had uncomplicated phacoemulsification with IOL implantation. Patients were examined by non-contact specular microscopy (NIDEK, CEM-530, Japan), preoperatively and postoperatively at regular follow-up periods (one, three, and six months postoperatively) with analysis of the endothelial cell density, percentage of hexagonal cells, CV, and CCT. RESULTS: By the end of follow-up period, there was a statistically significant reduction in ECD and HEX with a significant increase in CV and CCT in group one (DM-PEX). In group two (DM), a statistically significant decrease in ECD and HEX with a significant increase in CCT was reported, while in group three (PEX), the only significant difference was found in the form of ECD reduction. CONCLUSION: Patients with DM and PEX had significant changes regarding ECD, CV, HEX, and CCT which were more pronounced than in patients with DM only or PEX only. More attention should be paid while operating on diabetic patients with PEX to save corneal endothelium and decrease postoperative complications. STUDY REGISTRATION NUMBER: The study was retrospectively registered (16 July 2021) on ClinicalTrials.gov (NCT04965168).

Effect of Light Conditions and Accommodation on Implantable Phakic Contact Lens Vault by Anterior Segment Optical Coherence Tomography.

Purpose: To investigate the dynamic pupil and vault changes in eyes with implantable phakic contact lens (IPCL) under photopic and scotopic settings, as well as during accommodation using the anterior segment optical coherence tomography (AS-OCT). Methods: A prospective observational study included consecutive 36 eyes of myopic patients who underwent IPCL V2.0 implantation. Under photopic and scotopic light settings, as well as during accommodation, all patients were scanned using CASIA OCT (CASIA2; TOMEY, Nagoya, Japan). The pupil size, the vault (distance between the back surface of the IPCL and the anterior lens capsule), ACD-lens (distance between the posterior corneal surface and the anterior lens surface), IPCL-lens (distance between the posterior corneal surface and the anterior IPCL surface), and lens thickness (LT) were the study parameters. Results: The vault was significantly lower under photopic conditions (p-value<0.001). The pupil size was significantly smaller in photopic conditions (p-value<0.001). LT (p-value=0.975) and ACD-lens (p-value=0.917) were not significantly different between scotopic and photopic conditions, while the ACD-IPCL was significantly larger during photopic conditions (p-value=0.013). There were significant changes in all parameters between accommodative and non-accommodative conditions. Conclusion: The IPCL vault decreased significantly under photopic light conditions and accommodation.

Evaluation of the anterior chamber angle by anterior segment optical coherence tomography after implantable phakic contact lens implantation in myopic eyes.

PURPOSE: To evaluate the changes in the angle of the AC and lens vault after IPCL implantation by AS-OCT in myopic patients. METHODS: This was a prospective observational study involving 30 myopic eyes implanted with IPCL. AS-OCT was used to evaluate lens vault and AC angle parameters including anterior chamber angle, angle opening distance and trabecular-iris space area (TISA) at 1, 3 and 6 months postoperatively. RESULTS: All 3 AC angle parameters were significantly reduced at the 1st postoperative month compared to preoperative values, but remained stable thereafter with no significant change at the 3rd or 6th postoperative months. The lens vault showed no significant change over the entire follow-up period. CONCLUSION: IPCL implantation is a safe method for correction of myopia with stable AC angle narrowing over the course of 6 months postoperatively as monitored using AS-OCT.

Macular vessel density before and after panretinal photocoagulation in patients with proliferative diabetic retinopathy.

INTRODUCTION: Diabetic retinopathy (DR) is microangiopathy causing ischemia leading to proliferative diabetic retinopathy and macular edema. Panretinal photocoagulation (PRP) reverses the ischemia leading to regression of neovessels. Most previous studies showed the large vessel effects of PRP, while optical coherence tomography angiography (OCTA) allowed noninvasive quantification of microvascular retinal changes. AIM: To study the effect of PRP on microvascular retinal vessels in a detailed manner at different retinal and choroidal levels using OCTA. PATIENTS AND METHODS: This study was a prospective interventional study. 30 eyes of 18 diabetic patients with PDR were included. All patients were evaluated clinically and with OCTA (Avanti RTVue-XR system, Optovue) to evaluate superficial and deep vessels density (VDs), choroidal flow, and FAZ area before PRP (base line) and 1 month and 6 months after PRP. RESULTS: PRP improved vessels density at superficial (SCP), deep (DCP), and choriocapillaris levels. Foveal vessel density at SCP and DCP were statistically significantly increased. SCP was 28.76 ± 2.56 at base line and was increased to 29.84 ± 2.47 and 30.89 ± 2.20 after 1 month and after 6 months, respectively. DCP was 34.08 ± 5.59 at base line and was increased to 34.93 ± 5.66 and 36.09 ± 5.62 after 1 month and after 6 months, respectively. Foveal choriocapillaris was statistically significantly increased from 63.04 ± 2.66 at base line to 63.48 ± 2.65 and 63.98 ± 2.78 after 1 month and 6 months, respectively. Choroidal flow was increased from 1.74 ± 0.07 at base line to 1.75 ± 0.09 at 1 month which was nonsignificant (P = 0.72), but it was significantly increased to 1.87 ± 0.27 6 months after PRP (P = 0.009). FAZ area was significantly improved after PRP. FAZ area was decreased from 0.56 ± 0.27 at base line to 0.50 ± 0.21 after 1 month and to 0.46 ± 0.21 after 6 months. CONCLUSION: OCTA parameters were significantly improved by PRP in PDR patients, possibly due to redistribution of blood in occluded capillary plexuses. TRIALS REGISTRY: NCT04976361.

Anterior Segment Optical Coherence Tomography of Tear Film and Cornea in Systemic Lupus Erythematosus Patients.

PURPOSE: To study tear film and corneal thickness measurements in systemic lupus erythematosus (SLE) patients compared to age-matched controls using anterior segment optical coherence tomography (AS-OCT). METHODS: This was a cross-sectional study. Study participants were divided into 3 groups: Group A: SLE patients with clinical dry eye, Group B: SLE patients without clinical dry eye and Group C: healthy controls. The lower tear meniscus parameters measured using AS-OCT were tear meniscus height (TMH), tear meniscus depth (TMD) and tear meniscus area (TMA). The central corneal and corneal epithelial thickness were automatically calculated. RESULTS: The study included 40 eyes in Group A, 60 in Group B, and 100 in Group C. Mean age was 26.9±6.6 years for Group A, 27.6±7.3 years for Group B and 35.7±9.2 years for Group C (p= 0.06). All subjects were females except for 1 male patient in Group A. Mean TMH, TMA and TMD in Group C were 487.7±185.6 µm, 0.068±0.040 mm2, and 341.2±99.1 µm, respectively, which was significantly higher compared to Group A (225.5±27.9 µm, 0.018±0.004 mm2 and 171.9±26.0 µm, respectively, all p < 0.001) and Group B (395.4±118.8 µm, p < 0.001; 0.05±0.04 mm2, p=0.016 and 280.6±93.4 µm, p < 0.001, respectively). Group B eyes also had significantly higher parameters compared to Group A (all p < 0.001). Mean corneal and epithelial thickness in Group C were 501.6±37.5 µm and 53.3±4.5 µm, respectively, which was significantly higher compared to Group A (496.1±24.1 µm, p=0.044 and 49.5±3.5 µm, p < 0.001, respectively) and Group B (504.2±22.03 µm, p=0.046 and 47.5±5.6 µm, p < 0.001, respectively). Group B eyes also had a significantly higher corneal thickness (p=0.031) and epithelial thickness (p=0.011) compared to Group A. CONCLUSION: We demonstrated significant reduction of tear meniscus dimensions, central corneal thickness and epithelial thickness in SLE patients compared to age-matched controls using AS-OCT.