Reduced retinal vessel density in COVID-19 patients and elevated D-dimer levels during the acute phase of the infection.

PURPOSE: To describe macular vessel density and perfusion in COVID-19 patients using coherence tomography angiography (OCTA) and to investigate whether there is a correlation between retinal vascular abnormalities and clinical and laboratory parameters. METHODS: Cross-sectional analysis conducted at the Hospital Clinico San Carlos in Madrid, Spain. Patients with laboratory-confirmed COVID-19 that were attended in the Emergency Department (ED) from March 23 to March 29, 2020 were included. Fundus examination and OCTA were performed 4 weeks after being attended in ED. Macular OCTA parameters were analyzed and correlated with clinical (severity and hypoxemia- oxygen saturation < 92%) and laboratory parameters during hospital stay (D-Dimer-DD, lactate dehydrogenase-LDH and C-reactive protein-CRP). RESULTS: 80 patients were included, mean age 55(SD9) years old; 46.3% male. We reported macular vessel density and perfusion measurements in COVID-19 patients. Those patients with D-Dimer ≥ 500 ng/ml during SARS-CoV-2 infection had a decrease of central vessel density (mean difference 2.2; 95%CI 0.4-3.9) and perfusion density (mean difference 4.9; 95%CI 0.9-8.9) after the acute phase of COVID-19. These variations of vessel density and perfusion density were not documented in patients with LDH ≥ 500 U/L, CRP ≥ 10 mg/L and hypoxemia. CONCLUSIONS: COVID-19 patients showed short-term retinal vasculature abnormalities which may be related to a prothrombotic state associated with SARS-CoV-2 infection. Since the retinal microvasculature shares many morphological and physiological properties with the vasculature of other vital organs, further research is needed to establish whether patients with increased D-Dimer levels require more careful assessment and follow-up after COVID-19.

OBJETIVO: Evaluar la densidad vascular (DV) y la perfusión vascular (PV) retiniana en pacientes con COVID-19 mediante una angiografía por tomografía de coherencia óptica (OCTA), e investigar si existe una correlación entre las anomalías vasculares de la retina y los parámetros clínicos y de laboratorio. MÉTODOS: Análisis transversal realizado en el Hospital Clínico San Carlos, Madrid. Se incluyeron pacientes con diagnóstico confirmado de COVID-19 atendidos en el Servicio de Urgencias (SU) del 23 al 29 de marzo del 2020. Se realizó una exploración oftalmológica y OCTA cuatro semanas después de acudir al SU. Se analizaron los parámetros maculares de OCTA y se correlacionaron con parámetros clínicos (gravedad e hipoxemia-saturación de oxígeno < 92%) y de laboratorio durante la estancia hospitalaria (dímero D [DD], lactato deshidrogenasa [LDH] y proteína C reactiva [CRP]. RESULTADOS: Se incluyeron 80 pacientes, edad media 55 (DE nueve) años; 46,3% hombres. Las personas con DD > 500 ng/mL durante la infección por SARS-CoV-2 tuvieron una disminución de la DV central (diferencia de medias 2,2; IC 95% 0,4 a 3,9) y PV central (diferencia de medias 4,9; IC 95% 0,9 a 8,9) después de la fase aguda de COVID-19. Estas variaciones no se documentaron en los pacientes con LDH > = 500 U/L, CRP > = 10 mg/L y con hipoxemia. CONCLUSIONES: Los pacientes con COVID-19 mostraron anomalías de la vasculatura retiniana a corto plazo que pueden estar relacionadas con un estado protrombótico asociado con la infección por SARS-CoV-2. Dado que la microvasculatura de la retina comparte muchas propiedades morfológicas y fisiológicas con la vasculatura de otros órganos vitales, es necesario seguir investigando para determinar si los pacientes con niveles elevados de DD requieren una evaluación y un seguimiento más cuidadoso.

Optic nerve and macular optical coherence tomography in recovered COVID-19 patients.

PURPOSE: To investigate the peripapillary retinal nerve fiber layer thickness (RNFLT), macular RNFLT, ganglion cell layer (GCL), and inner plexiform layer (IPL) thickness in recovered COVID-19 patients compared to controls. METHODS: Patients previously diagnosed with COVID-19 were included, while healthy patients formed the historic control group. All patients underwent an ophthalmological examination, including macular and optic nerve optical coherence tomography. In the case group, socio-demographic data, medical history, and neurological symptoms were collected. RESULTS: One hundred sixty patients were included; 90 recovered COVID-19 patients and 70 controls. COVID-19 patients presented increases in global RNFLT (mean difference 4.3; CI95% 0.8 to 7.7), nasal superior (mean difference 6.9; CI95% 0.4 to 13.4), and nasal inferior (mean difference 10.2; CI95% 2.4 to 18.1) sectors of peripapillary RNFLT. Macular RNFL showed decreases in COVID-19 patients in volume (mean difference -0.05; CI95% -0.08 to -0.02), superior inner (mean difference -1.4; CI95% -2.5 to -0.4), nasal inner (mean difference -1.1; CI95% -1.8 to -0.3), and nasal outer (mean difference -4.7; CI95% -7.0 to -2.4) quadrants. COVID-19 patients presented increased GCL thickness in volume (mean difference 0.04; CI95% 0.01 to 0.07), superior outer (mean difference 2.1; CI95% 0.8 to 3.3), nasal outer (mean difference 2.5; CI95% 1.1 to 4.0), and inferior outer (mean difference1.2; CI95% 0.1 to 2.4) quadrants. COVID-19 patients with anosmia and ageusia presented an increase in peripapillary RNFLT and macular GCL compared to patients without these symptoms. CONCLUSIONS: SARS-CoV-2 may affect the optic nerve and cause changes in the retinal layers once the infection has resolved.

Reduced retinal vessel density in COVID-19 patients and elevated D-dimer levels during the acute phase of the infection.

PURPOSE: To describe macular vessel density and perfusion in COVID-19 patients using coherence tomography angiography (OCTA) and to investigate whether there is a correlation between retinal vascular abnormalities and clinical and laboratory parameters. METHODS: Cross-sectional analysis conducted at the Hospital Clinico San Carlos in Madrid, Spain. Patients with laboratory-confirmed COVID-19 that were attended in the Emergency Department (ED) from March 23 to March 29, 2020 were included. Fundus examination and OCTA were performed 4 weeks after being attended in ED. Macular OCTA parameters were analyzed and correlated with clinical (severity and hypoxemia- oxygen saturation<92%) and laboratory parameters during hospital stay (D-Dimer-DD, lactate dehydrogenase-LDH and C-reactive protein-CRP). RESULTS: 80 patients were included, mean age 55(SD9) years old; 46.3% male. We reported macular vessel density and perfusion measurements in COVID-19 patients. Those patients with D-Dimer≥500ng/ml during SARS-CoV-2 infection had a decrease of central vessel density (mean difference 2.2; 95%CI 0.4-3.9) and perfusion density (mean difference 4.9; 95%CI 0.9-8.9) after the acute phase of COVID-19. These variations of vessel density and perfusion density were not documented in patients with LDH≥500U/L, CRP≥10mg/L and hypoxemia. CONCLUSIONS: COVID-19 patients showed short-term retinal vasculature abnormalities which may be related to a prothrombotic state associated with SARS-CoV-2 infection. Since the retinal microvasculature shares many morphological and physiological properties with the vasculature of other vital organs, further research is needed to establish whether patients with increased D-Dimer levels require more careful assessment and follow-up after COVID-19.