Optical coherence tomography angiography for screening of hydroxychloroquine-induced retinal alterations.

BACKGROUND/AIMS: The purpose of the study was to evaluate the retinal and choroidal changes via optical coherence tomography angiography (OCTA) in patients who received hydroxychloroquine (HCQ). METHODS: Sixty eyes of 60 female patients who received HCQ were included in the study. Patients were categorized into two groups as high-risk (≥ 5 years) and low-risk (< 5 years) in terms of HCQ-induced retinal toxicity. Spectral domain-OCT, OCTA, and visual field tests were performed. Retinal thickness, vascular density, flow rates, choroidal thickness (CT), and visual field parameters were compared between the groups, and the correlation between total HCQ cumulative dose, duration of use, and these parameters was assessed. RESULTS: Compared to low-risk group, patients in the high-risk group had vascular density loss (p < 0.05). In this group, foveal avascular zone (FAZ) was found to be wider (p < 0.05). Retinal and choroidal flow rates were found to be decreased markedly in the high-risk group (p < 0.05). CT was found to be thinner in the high-risk group (p < 0.05). HCQ cumulative dose and duration of use had a negative significant correlation with all vascular density, flow rate, CT parameters, and positive significant correlation with FAZ parameters (p < 0.05). In visual field tests, mean defect (MD) was found to be increased in the high-risk group (p < 0.05). Moreover, MD had a positive correlation with HCQ cumulative dose and duration of use (p < 0.05). CONCLUSIONS: Evaluation of microvascular changes via OCTA may contribute to the early detection of HCQ-induced retinal toxicity, which cannot be detected through other imaging devices, at the stage when it is reversible.

Evaluation of optical coherence tomography angiographic findings in Alzheimer's type dementia.

BACKGROUND/AIMS: To identify the retinal vascular pathologies in patients with Alzheimer's type dementia (ATD) through optical coherence tomography angiography (OCTA) imaging. METHODS: Our study included 26 patients in the patient group, and age-matched and sex-matched 26 subjects in the control group. A detailed ophthalmological and neurological examination was performed for all subjects included in the study. The retinal, choroidal vascular structures and choroidal thickness (CT) of all subjects were analysed in a detailed way with a commercial spectral domain OCTA. Moreover, all participants underwent detailed neurological examination including Mini Mental State Examination (MMSE) test to evaluate cognitive function. RESULTS: In the group of patients with ATD, the MMSE score was significantly lower than that of the control group (p<0.001). The retinal vascular density was significantly lower than that of the control group in all zones (p<0.05). Foveal avascular zone (FAZ) was significantly enlarged compared with the control group (p=0.001). CT was significantly lower in the group of patients with ATD (p<0.001). Outer retinal and choroidal flow rates were lower in the group of patients with ATD, while the difference was not significant (p>0.05). Furthermore, significant correlation was found between the MMSE and all vascular density parameters, CT parameter and FAZ tested with OCTA imaging (p<0.05). CONCLUSIONS: In patients with ATD, retinal and choroidal vascular pathologies detected through OCTA imaging can be used as a new biomarker in the early diagnosis of the disease, follow-up of its progression and in investigating the efficacy of the drugs.

Bifid right lateral rectus: a case report.

Abnormal insertions are the commonest cause of congenital defects in ocular motility. In this paper, a patient with a bifid right lateral rectus muscle is presented and discussed. To the best of our knowledge this patient is the first known case of an abnormal bifid lateral rectus muscle with no systemic association.