PMC7674622_01
(A) Case 1: 48-year-old, COVID-19-positive female with altered mental status; 3-T MRI axial FLAIR image (red arrows) of hyperintense FLAIR in the medial temporal lobe because of altered mental status and seizures, unable to hold still for scan, with resultant motion artifact. (B-D) Case 2: 29-year-old, COVID-19-positive female who presented with seizures. (B) 1.5-T MRI axial FLAIR (red arrow) of the left temporal lobe with hemorrhagic venous infarction, with the FLAIR hyperintensity consistent with edema and mass effect effacing the left ambient cistern. (C) 1.5-T MRI:time-of-flight MRI:with red arrows noting the absent flow void with venous thrombosis of the left transverse and sigmoid sinus and the left internal jugular vein. (D) CT venogram with the purple arrow demonstrating absent contrast enhancement and thrombosis of the left transverse and sigmoid sinus.
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F1
Non-contrast CT of the head revealed edema, mass effect, and subcortical hemorrhages in the left temporal and parietal lobes as well as a hyperdense left transverse sigmoid sinus (Figure 1).
PMC7674622_02
(A) Case 1: 48-year-old, COVID-19-positive female with altered mental status; 3-T MRI axial FLAIR image (red arrows) of hyperintense FLAIR in the medial temporal lobe because of altered mental status and seizures, unable to hold still for scan, with resultant motion artifact. (B-D) Case 2: 29-year-old, COVID-19-positive female who presented with seizures. (B) 1.5-T MRI axial FLAIR (red arrow) of the left temporal lobe with hemorrhagic venous infarction, with the FLAIR hyperintensity consistent with edema and mass effect effacing the left ambient cistern. (C) 1.5-T MRI:time-of-flight MRI:with red arrows noting the absent flow void with venous thrombosis of the left transverse and sigmoid sinus and the left internal jugular vein. (D) CT venogram with the purple arrow demonstrating absent contrast enhancement and thrombosis of the left transverse and sigmoid sinus.
fneur-11-576329-g0001.jpg
PMC7674622_02_fneur-11-576329-g0001.jpg
F1
Non-contrast CT of the head revealed edema, mass effect, and subcortical hemorrhages in the left temporal and parietal lobes as well as a hyperdense left transverse sigmoid sinus (Figure 1).
PMC7674622_03
(A-F) Case 3: 64-year-old COVID-positive female, axial 3-T MRI. (A-C) Axial FLAIR. (D,E) Axial DWI. (F) Axial apparent diffusion coefficient (ADC). FLAIR hyperintensity in the left was greater than that in the right cerebral hemispheres, with punctate DWI hyperintensity (red arrowheads) with ADC restricted diffusion. (F) Left precentral sulcus and right superior medial right parietal lobe, foci of FLAIR, DWI hyperintensity without restricted diffusion, and ADC T2-shine through, concerning posterior reversible encephalopathy in a patient with elevated blood pressure.
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F2
Brain MRI without gadolinium, due to kidney dysfunction, showed punctate diffusion positive lesions in the left precentral sulcus and superior right medial parietal subcortical regions as well as patchy T2 prolongation in the left frontal, occipital, and bilateral parietal and cerebellar regions, most consistent with posterior reversible encephalopathy syndrome (PRES) (Figure 2).
PMC7674622_04
(A-H) Case 4: 68-year-old, COVID-positive female. (A,B) Hyperfine 0.064-T portable MRI obtained 26 days after admission at the patient's bedside showing focal T2 and FLAIR hyperintensities (red arrows). (C-H) 3-T MRI obtained 39 days after admission. (C) Axial T2 and (D) axial FLAIR hyperintensities (red arrows): left subinsular cortex, lentiform nuclei, thalami, and left temporal lobe. (E,F) Axial FLAIR, (G) axial ADC, (H) axial DWI, T2, FLAIR, and DWI hyperintensities (red arrows): bilateral olfactory tracts, medial temporal lobes including hippocampal tails, caudate heads, fornices and posterior commissural fibers, right posterior lateral temporal lobe without restricted diffusion.
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F3
On day 26, portable 0.06-T MRI (Hyperfine) of the brain without contrast was performed, showing areas of T2 and FLAIR hyperintensity in the left thalamus and lentiform nuclei, though technically limited (Figure 3). A follow-up 3-T contrast-enhanced brain MRI on day 39 showed T2, FLAIR, and diffusion-weighted imaging (DWI) hyperintensity without restricted diffusion along the bilateral olfactory tracts, caudate heads, posterior commissural fibers of the fornices, hippocampal tails, and right temporal lobe (Figure 3).
(A,B) Case 4. Video EEG results. (A) Day 1 showing the high-amplitude rhythmic sharply contoured; intermixed 3- and 6-Hz activity concerning non-convulsive status epilepticus. (B) Day 2 with resolution of rhythmic slowing after the administration of lorazepam and levetiracetam, corresponding with improved mentation. Low-frequency filter, 1 Hz; high-frequency filter, 70 Hz; sensitivity, 7 muV/mm; timebase, 30 mm/s.
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F4
EEG on day 33 revealed unremitting high-amplitude centrotemporal sharp rhythmic 3-5-Hz activity concerning non-convulsive status epilepticus (NCSE) (Figure 4).