Clinical and Neuroimaging Characteristics of Ischemic Stroke in Rhino-Orbito-Cerebral Mucormycosis Associated with COVID-19.

Purpose: The aim of this study was to compare clinical, neuroimaging, and laboratory features of rhino-orbito-cerebral mucormycosis (ROCM) in COVID-19 patients with and without ischemic stroke complications.

Methods: This observational study was conducted between August and December 2021 and 48 patients who had confirmed ROCM due to COVID-19, according to neuroimaging and histopathology/mycology evidence were included. Brain, orbit and paranasal sinus imaging was performed in all included patients. Data pertaining to clinical, neuroimaging, and laboratory characteristics and risk factors were collected and compared between patients with and without ischemic stroke complications.

Results: Of the patients 17 were diagnosed with ischemic stroke. Watershed infarction was the most common pattern (N = 13, 76.4%). Prevalence of conventional risk factors of stroke showed no significant differences between groups (patients with stroke vs. without stroke). Cavernous sinus (p = 0.001, odds ratio, OR = 12.8, 95% confidence interval, CI: 2.3-72) and ICA (p < 0.001, OR = 16.31, 95%CI: 2.91-91.14) involvement was more common in patients with stroke. Internal carotid artery (ICA) size (on the affected side) in patients with ischemic stroke was significantly smaller than in patients without stroke (median = 2.4 mm, interquartile range, IQR: 1.3-4 vs. 3.8 mm, IQR: 3.2-4.3, p = 0.004). Superior ophthalmic vein (SOV) size (on the affected side) in patients with stroke was significantly larger than patients without stroke (2.2 mm, IQR: 1.5-2.5 vs. 1.45 mm IQR: 1.1-1.8, p = 0.019). Involvement of the ethmoid and frontal sinuses were higher in patients with stroke (p = 0.007, OR = 1.85, 95% CI: 1.37-2.49 and p = 0.011, OR = 5, 95% CI: 1.4-18.2, respectively). Patients with stroke had higher D‑dimer levels, WBC counts, neutrophil/lymphocyte ratios, and BUN/Cr ratio (all p < 0.05).

Conclusion: Stroke-related ROCM was not associated with conventional ischemic stroke risk factors. Neuroimaging investigations including qualitative and quantitative parameters of cavernous sinus, ICA and SOV are useful to better understand the mechanism of stroke-related ROCM in COVID-19 patients.