COVID-19 and the Eye: Ocular Manifestations, Treatment and Protection Measures.

The novel pandemic coronavirus disease 2019 (COVID-19) leading to health and economic problems worldwide is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Although COVID-19 mainly occurs as a lower respiratory tract infection, there is multiorgan involvement in infected patients. The disease is transmitted from person to person through air droplets or contact with contaminated surfaces. SARS-CoV-2 leads to this systemic involvement by attaching to angiotensin-converting enzyme 2 (ACE2) receptors located on several human cells. Since SARS-CoV-2 RNA has been found in tears of infected patients, ocular surface may allow the virus to transmit to nasopharynx via the nasolacrimal duct. This narrative review aims to sum up all segmental ocular complications, ocular adverse effects of COVID-19 treatment, and preventive measures suggested to minimize the SARS-CoV-2 transmission between patients and ophthalmologists by reviewing currently available literature.

Do we need to evaluate patients with spontaneous subconjunctival haemorrhage for bleeding disorders?

AIM OF THE STUDY: Subconjunctival haemorrage (SCH) is a frequent bleeding manifestation and a common cause of visits to the primary care. Trauma in young patients and vascular damage such as hypertension in the elderly are the most common causes of SCH and the prevalence of haematological diseases is <1%. We aimed to evaluate the prevalence of congenital or acquired bleeding disorders in patients with once or recurrent SCH. METHODS USED TO CONDUCT THE STUDY: It is a retrospective study and included fifty-two patients with SCH whose aetiologic factor was not detected. Haemostatic tests were studied in 52 patients (25 male and 27 females). All patients included were evaluated for congenital or acquired bleeding disorder and SCH with once and those with two or more were compared for the laboratory results. RESULTS OF THE STUDY: Type I von Willebrand disease (vWD) was diagnosed in one patient with recurrent SCH and one patient with single SCH (3.8%). The prevalence of patients with type 1 vWD in the study was not statistically significant when compared with the frequency of vWD in the normal population. Fibrinogen level was found to be statistically higher in patients who had SCH once than those who had recurrent SCH. However, fibrinogen level was in normal range in all patients. CONCLUSIONS DRAWN FROM THE STUDY AND CLINICAL IMPLICATIONS: There was no increase in the incidence of congenital or acquired bleeding disorder in SCH compared with normal population. Fort this reason, it was thought there was no need for evaluation for bleeding disorders in spontaneous SCH.

The association of choroidal thickness with rheumatoid factor and anti-cyclic citrullinated peptide in rheumatoid arthritis.

PURPOSE: To measure ocular vascular parameters in rheumatoid arthritis patients and compare with those of controls and to evaluate the association of rheumatoid factor and anti-cyclic citrullinated peptide antibody with the choroidal thickness. METHODS: Superficial foveal vessel density, superficial and deep foveal avascular zone area, and subfoveal choroidal thickness were measured using the swept-source optical coherence tomography angiography. Multivariate linear regression was used to assess the correlation of subfoveal choroidal thickness with serological markers in patients with rheumatoid arthritis. RESULTS: Choroidal thickness in patients was significantly thinner than that in healthy controls (278.87 ± 59.54 µm vs. 323.94 ± 98.02 µm, p = 0.03). Despite the weak positive correlations between rheumatoid factor/anti-cyclic citrullinated peptide and choroidal thickness, these relationships were not statistically significant (p > 0.05). CONCLUSIONS: In patients with rheumatoid arthritis, subfoveal choroid was thinner than controls. There were similar correlations between choroidal thickness and rheumatoid factor and anti-cyclic citrullinated peptide antibody.

Topographic changes measured by the swept source optical coherence tomography in retinal nerve fiber layer, optic nerve head and macula in children with migraine.

As a vascular-inflammatory disease, migraine affects the brain and some other organs, such as the eye. The aim of this study was to measure and compare the peripapillary retinal nerve fiber layer (RNFL) thickness, macular ganglion cell layer thickness and optic nerve head parameters to detect structural damage in children with migraine using swept-source optical coherence tomography. Twenty-four children with migraine in the painless period and 26 controls were included in the study. The vast majority of the groups consisted of females (75% for patients and 77% for controls). Certain RNFL quadrants and optic disc parameters revealed significant differences between the patients and controls. In the right and left eyes of children with migraine, nasal quadrant RNFL was significantly thicker than that in healthy subjects (88.82 ± 11.03 vs 77.80 ± 13.77, P = 0.004 for right eyes and 87.71 ± 11.79 vs 77.80 ± 13.77, P = 0.01 for left eyes). Temporal quadrant RNFL in the left eyes was thinner (78.67 ± 9.57 vs 84.44 ± 9.68, P = 0.04). Disc area in the left eyes of the patients was greater (2.29 ± 0.46 vs 1.94 ± 0.28, P = 0.003). There were significant expansions in cup volumes in favor of the patients for right and left eyes (0.15 ± .0.19 vs 0.05 ± 0.05, P = 0.03 and 0.17 ± 0.14 vs 0.05 ± 0.05, P = 0.001, respectively). The only significant difference between the left and right eyes of the migraineurs was the RNFL thickness in the superior quadrant. Ganglion cell layer thickness did not differ between the right eyes, left eyes and controls. In conclusion, children with migraine showed significant variations in specific RNFL and optic disc parameters compared to control subjects.

Quantitative analysis of the retinal nerve fiber layer, ganglion cell layer and optic disc parameters by the swept source optical coherence tomography in patients with migraine and patients with tension-type headache.

The aim of the study was to measure the thicknesses of the inner retinal segments and optic nerve head (ONH) parameters in migraineurs and patients with tension-type headache (TTH) in headache-free period using swept source optical coherence tomography (SS-OCT) and to compare the outcomes with each other and those of healthy subjects. The study population consisted of 23 migraineurs, 22 TTH patients, and 25 controls with a best-corrected visual acuity of 20/20 and without a history of systemic or ocular disease. Macular ganglion cell inner plexiform layer (mGCIPL), macular ganglion cell complex (mGCC), circumpapillary retinal nerve fiber layer (cpRNFL), and ONH parameters were evaluated using SS-OCT, and the areas under the receiver-operating characteristic (ROC) curves were calculated to determine the ability of these parameters to distinguish between the patient and normal eyes. There were not statistically significant differences between the measurements acquired from migraineurs, TTH patients, and the controls. The outcomes of the patients with TTH were very similar to those of the normal participants. The areas under the ROC curves (AUC) correlated highly with the measurements obtained from the same subfields for the mGCC, MGCIPL, cpRNFL, and ONH parameters. In conclusion, SS-OCT presented reproducible and reliable measurements of posterior segment layers of the eyes, especially in sectoral configuration, and the parameters did not show significant difference between the groups.

Detection of Glycemia and Osmolarity Changes Using Eye Examinations.

Background: Glycated hemoglobin (HbA1c) is an index of the average blood glucose level over the preceding 2-3 months. In experimental studies, the lens responded to changes in osmolarity by forming vacuoles. By observing the vacuoles of the lens during eye examination, can we detect changes in osmolarity and glycemia over the last 6 months through HbA1c levels? Methods: In total, 400 patients (mean age, 67.7 ± 9.8 years), including those with diabetes mellitus, hypertension, and heart failure, were included in the study. The control group contained 70 patients matched in terms of age and sex and who had no prior disease (mean age, 67.8 ± 9.4 years). Monthly Na, glucose, and blood urea nitrogen values were used to calculate changes in osmolarity over 6 months. HbA1c values were also recorded. Biomicroscopy was used to evaluate lens vacuolation; all vacuoles were digitally photographed and converted to ImageJ format. Results: The sensitivity and specificity of using large vacuoles to detect HbA1c ≥10% were 88.0% (95% confidence interval [CI]: 68.8-97.4) and 82.6% (95% CI: 74.1-89.2), respectively. The sensitivity and specificity of detecting a 10 mOsm/kg change in osmolarity were 61% (95% CI: 48.9-72.4) and 94.5% (95% CI: 91.5-96.7), respectively. Conclusions: Lens vacuoles, which can be observed with a simple and quick examination, can be used to detect HbA1c levels and osmolarity changes over the last 6 months. Because of their relationship to the severity of retinopathy, vacuoles can also be used as a weak control indicator.