BackgroundGlobal pandemic SARS-CoV-2 causes a prothrombotic state without fully elucidated effects. This study aims to analyse and quantify the possible retinal microvascular abnormalities.Materials and methodsCase–control study. Patients between 18 and 55 years old with PCR-confirmed SARS-CoV-2 infection within the last 3 months were included. Risk stratification: group 1—mild disease (asymptomatic/paucisymptomatic); group 2—moderate disease (required hospital admission with no acute respiratory distress) and group 3—severe disease (subjects who developed an acute respiratory distress were admitted in the intensive care unit and presented interleukin 6 values above 40 pg/mL). Age-matched volunteers with negative serology tests were enrolled to control group. A colour photograph, an optical coherence tomography (OCT) and an angiography using OCT centred on the fovea were performed.ResultsControl group included 27 subjects: group 1 included 24 patients, group 2 consisted of 24 patients and 21 participants were recruited for group 3. There were no funduscopic lesions, neither in the colour images nor in the structural OCT. Fovea-centred vascular density (VD) was reduced in group 2 and group 3 compared with group 1 and control group (control group vs group 2; 16.92 vs 13.37; p=0.009) (control group vs group 3; 16.92 vs .13.63; p=0.026) (group 1 vs group 2; 17.16 vs 13.37; p=0.006) (group 1 vs group 3; 17.16 vs 13.63 p=0.017).ConclusionPatients with moderate and severe SARS-CoV-2 pneumonia had decreased central retinal VD as compared with that of asymptomatic/paucisymptomatic cases or control subjects.
A high rate of asymptomatic retinal abnormalities was detected in this general screening, justifying this practice. Many patients who visit optometrists in Spain are unaware that they would benefit from ophthalmological monitoring. The ophthalmic community should lead initiatives of the type presented to preserve and guarantee quality standards.
Type 2 diabetes is associated with a high risk of cognitive impairment and dementia. Therefore, strategies are needed to identify patients who are at risk for dementia. Given that the retina is a brain-derived tissue, it may provide a noninvasive way to examine brain pathology. The aims of this study were to evaluate whether retinal sensitivity ) correlates with the specific parameters of brain imaging related to cognitive impairment and) discriminates patients with diabetes with mild cognitive impairment (MCI) from those with normal cognition and those with Alzheimer disease (AD). For this purpose, a prospective, nested case-control study was performed and included 35 patients with type 2 diabetes without cognitive impairment, 35 with MCI, and 35 with AD. Retinal sensitivity was assessed by Macular Integrity Assessment microperimetry, and a neuropsychological evaluation was performed. Brain neurodegeneration was assessed by MRI and fludeoxyglucose-18 positron emission tomography (FDG-PET). A significant correlation was found between retinal sensitivity and the MRI and FDG-PET parameters related to brain neurodegeneration. Retinal sensitivity was related to cognitive status (normocognitive> MCI > AD; < 0.0001). Our results suggest that retinal sensitivity assessed by microperimetry is related to brain neurodegeneration and could be a useful biomarker for identifying patients with type 2 diabetes who are at risk for developing AD.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.