High-resolution intracranial vessel wall imaging in cerebral viral infections evaluations.

PURPOSE: Vascular complications can be seen in various viral CNS infections. Variable neuro-imaging findings have been described in the literature elucidating the parenchymal changes with vascular involvement. Vessel wall imaging (VWI) can help to detect these vascular involvements. We aimed to describe the role and usefulness of VWI in the evaluation of various viral CNS infections. METHODS: In this prospective study, we included 15 cases of various diagnosed viral CNS infections (varicella, HIV encephalopathy, HSV encephalitis, Japanese encephalitis, dengue, COVID-19). VWI and time-of-flight MR angiography (TOF MRA) were included in imaging protocol. All cases were evaluated for the presence of cerebral parenchymal changes, vascular enhancement, and vascular stenosis. RESULTS: We found infarctions in all 5 cases of varicella, 1 case of HIV encephalopathy, and 1 case of COVID-19 encephalopathy. All these cases also showed vascular enhancement and stenosis on VWI. The rest of the cases, including 1 case of HIV encephalopathy, 3 cases of herpes encephalitis, 2 cases of dengue, and 2 cases of Japanese encephalitis did not have any vascular complication, and also did not show vascular enhancement or stenosis. CONCLUSION: VWI can be useful in the detection of vascular involvement in various viral infections of CNS which show a relatively higher cerebrovascular complication rate like varicella, HIV encephalopathy, and COVID-19. However, VWI may not be useful in the routine evaluation of other viral infections like herpes, dengue, and Japanese encephalitis, which have a very low rate of cerebrovascular complication rate.

Hemodynamic differences by increasing low profile visualized intraluminal support (LVIS) stent local compaction across intracranial aneurysm orifice.

BACKGROUND: The Low-profile Visualized Intraluminal Support device (LVIS) has been successfully used to treat cerebral aneurysm, and the push-pull technique has been used clinically to compact the stent across aneurysm orifice. Our aim was to exhibit the hemodynamic effect of the compacted LVIS stent. METHODS: Two patient-specific aneurysm models were constructed from three-dimensional angiographic images. The uniform LVIS stent, compacted LVIS and Pipeline Embolization Device (PED) with or without coil embolization were virtually deployed into aneurysm models to perform hemodynamic analysis. Intra-aneurysmal flow parameters were calculated to assess hemodynamic differences among different models. RESULTS: The compacted LVIS had the highest metal coverage across the aneurysm orifice (case 1, 46.37%; case 2, 67.01%). However, the PED achieved the highest pore density (case 1, 19.56 pores/mm2; case 2, 18.07 pores/mm2). The compacted LVIS produced a much higher intra-aneurysmal flow reduction than the uniform LVIS. The PED showed a higher intra-aneurysmal flow reduction than the compacted LVIS in case 1, but the results were comparable in case 2. After stent placement, the intra-aneurysmal flow was further reduced as subsequent coil embolization. The compacted LVIS stent with coils produced a similar reduction in intra-aneurysmal flow to that of the PED. CONCLUSIONS: The combined characteristics of stent metal coverage and pore density should be considered when assessing the flow diversion effects of stents. More intra-aneurysmal flow reductions could be introduced by compacted LVIS stent than the uniform one. Compared with PED, compacted LVIS stent may exhibit a flow-diverting effect comparable to that of the PED.

A cardiovascular magnetic resonance imaging-based pilot study to assess coronary microvascular disease in COVID-19 patients.

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and is primarily characterised by a respiratory disease. However, SARS-CoV-2 can directly infect vascular endothelium and subsequently cause vascular inflammation, atherosclerotic plaque instability and thereby result in both endothelial dysfunction and myocardial inflammation/infarction. Interestingly, up to 50% of patients suffer from persistent exercise dyspnoea and a post-viral fatigue syndrome (PVFS) after having overcome an acute COVID-19 infection. In the present study, we assessed the presence of coronary microvascular disease (CMD) by cardiovascular magnetic resonance (CMR) in post-COVID-19 patients still suffering from exercise dyspnoea and PVFS. N = 22 patients who recently recovered from COVID-19, N = 16 patients with classic hypertrophic cardiomyopathy (HCM) and N = 17 healthy control patients without relevant cardiac disease underwent dedicated vasodilator-stress CMR studies on a 1.5-T MR scanner. The CMR protocol comprised cine and late-gadolinium-enhancement (LGE) imaging as well as velocity-encoded (VENC) phase-contrast imaging of the coronary sinus flow (CSF) at rest and during pharmacological stress (maximal vasodilation induced by 400 µg IV regadenoson). Using CSF measurements at rest and during stress, global myocardial perfusion reserve (MPR) was calculated. There was no difference in left ventricular ejection-fraction (LV-EF) between COVID-19 patients and controls (60% [57-63%] vs. 63% [60-66%], p = NS). There were only N = 4 COVID-19 patients (18%) showing a non-ischemic pattern of LGE. VENC-based flow measurements showed that CSF at rest was higher in COVID-19 patients compared to controls (1.78 ml/min [1.19-2.23 ml/min] vs. 1.14 ml/min [0.91-1.32 ml/min], p = 0.048). In contrast, CSF during stress was lower in COVID-19 patients compared to controls (3.33 ml/min [2.76-4.20 ml/min] vs. 5.32 ml/min [3.66-5.52 ml/min], p = 0.05). A significantly reduced MPR was calculated in COVID-19 patients compared to healthy controls (2.73 [2.10-4.15-11] vs. 4.82 [3.70-6.68], p = 0.005). No significant differences regarding MPR were detected between COVID-19 patients and HCM patients. In post-COVID-19 patients with persistent exertional dyspnoea and PVFS, a significantly reduced MPR suggestive of CMD-similar to HCM patients-was observed in the present study. A reduction in MPR can be caused by preceding SARS-CoV-2-associated direct as well as secondary triggered mechanisms leading to diffuse CMD, and may explain ongoing symptoms of exercise dyspnoea and PVFS in some patients after COVID-19 infection.

[A case of cerebral embolism with Coronavirus disease 2019].

A 63-year-old man, who had persistent fever for a month, was admitted to the hospital with sudden left arm palsy with a National Institutes of Health Stroke Scale score of 3. Consequently, brain MRI showed hyperintensity of the bilateral occipital, right parietal, and right frontal lobes on diffusion-weighted imaging. Moreover, FLAIR presented hyperintensity of the left occipital lobe. Magnetic resonance angiography detected the deficit of the blood-flow signal of the horizontal segment of the middle cerebral artery. He was diagnosed with acute ischemic stroke. In addition, chest CT showed ground-glass opacities, and test to detect SARS-CoV-2 was positive. Cerebral embolism was suspected. However, the source was unknown. His ischemic stroke was possibly associated with coagulation abnormality caused by coronavirus disease 2019.

Focal Cerebral Arteriopathy in a Young Adult Following SARS-CoV2 Reinfection.

Ten days after SARS-Cov2 reinfection with mild gastrointestinal symptoms and headache that occurred 2 months after an initial infection, a previously healthy 37-year-old woman developed fluctuating facial and upper limb paresthesia and weakness. Diffusion-weighted magnetic resonance imaging revealed ischemic lesions in the right parietal region of different stages within the same vascular territory. A cerebral angiography demonstrated an isolated focal arteriopathy with no other arterial involvement. Focal cerebral arteriopathy is exceedingly rare among adults and most commonly triggered by varicella-zoster virus reactivation. We present a case of focal cerebral arteriopathy in a patient with a recent reinfection with SARS-CoV-2.

COVID-19 associated intracranial vasculopathy-MRI vessel wall imaging as adjunct to emergent CT angiography-a case report.

COVID-19 was initially described as a pulmonary disease. Increasing attention is now directed to extrapulmonary disease manifestations mediated by viral tropism to the vascular endothelium. Here, we report a case of an adult patient with COVID-19 who presented to the emergency department with neurological signs disproportionate to pulmonary symptoms and was found to have a subacute ischemic stroke. Imaging studies suggested an active inflammatory vasculopathy. The case highlights the utility of vascular wall imaging studies when positive findings are present on emergent CT angiography. Current treatment algorithms should consider the addition of adjunct intracranial vessel wall imaging to assess for inflammatory vasculopathy when a patient with acute or recent COVID infection presents to the emergency department with stroke.

Contained Rupture of a Posterior Communicating Artery Aneurysm in a Patient With a Third Nerve Palsy.

ABSTRACT: It is recommended that every patient with a new third nerve palsy undergo urgent neuroimaging (computed tomography angiography or magnetic resonance angiography) to exclude a posterior communicating artery aneurysm. Because of the novel coronavirus (COVID-19) pandemic, our institution noted a significant decline in the number of patients with aneurysmal subarachnoid hemorrhage presenting to the hospital. We report one such example of a patient who developed new-onset severe headache and vomiting and did not seek medical attention because of COVID-19. Two months later, she was noted to have ptosis during a routine follow-up and was found to have a complete, pupil-involving third nerve palsy. Computed tomography angiography was performed and revealed an irregular bilobed saccular aneurysm (7 × 9 × 5 mm) of the right posterior communicating (PComm) artery, but no acute hemorrhage was visible on CT. On MRI, immediately adjacent to the aneurysm, there was a small subacute hematoma in the right medial temporal lobe with surrounding vasogenic edema. This case had a fortunate and unique outcome as she had a contained hematoma adjacent to the ruptured PComm aneurysm and did not experience severe morbidity from the subarachnoid hemorrhage nor did she rebleed in the interval in which she did not seek care. This case highlights the importance of providing neuro-ophthalmic care even during a pandemic.

Cerebrovascular Complications and Vessel Wall Imaging in COVID-19 Encephalopathy-A Pilot Study.

BACKGROUND AND PURPOSE: Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with several complications of the central nervous system (CNS), including acute encephalopathy. METHODS: In this pilot study, we report a series of 39 patients (66.5 ± 9.2 years; 10.3% female) with acute encephalopathy, who underwent a standard brain magnetic resonance imaging (MRI) at 1.5 T during the acute symptomatic phase. In addition to diffusion-weighted imaging, MR angiography and susceptibility-weighted images, high-resolution vascular black blood sequences (in 34 cases) were used to investigate the vasculature of the brain. RESULTS: In 29 out of 34 patients with COVID-19 encephalopathy (85%) with high-resolution vessel wall imaging, we found a circular enhancement and thickening of the basilar and vertebral arteries, without any correlation with ischemia or microbleeds (reported in 21% and 59%, respectively). CONCLUSION: We report a high prevalence of vascular changes suggestive of endotheliitis as reported in other organs. This could suggest an inflammatory mechanism underlying this encephalopathy.

Cerebral vasculitis of medium-sized vessels as a possible mechanism of brain damage in COVID-19 patients.

BACKGROUND AND PURPOSE: Cerebral complications related to COVID-19 were recently reported, and the underlying mechanisms of brain damage remain uncertain, probably multifactorial. Among various hypotheses suggested, a possible vasculitis was issued but never confirmed. Herein, we aimed to describe brain MRIs focused on the intracranial vessel wall in a population of COVID-19 patients with neurologic manifestations. MATERIALS AND METHODS: Between March 1 and May 31, 2020, 69 consecutive COVID-19 patients with neurologic manifestations underwent a brain MRI allowing the study of the intracranial vessel wall at Strasbourg University hospitals and were retrospectively included. During the same period, 25 consecutive patients, without suspicion of SARS-CoV-2 infection, underwent a brain MRI urgently, with the same imaging protocols. A vasculitis seemed likely when imaging demonstrated vessel wall thickening with homogeneous and concentric enhancement. RESULTS: Among the 69 COVID-19 patients included, 11 (16%) presented arterial vessel wall thickening with homogeneous and concentric enhancement, compatible with cerebral vasculitis. These neuroimaging findings were not found among the 25 patients without SARS-CoV-2 infection, and the difference was statistically significant (p = 0.03). Middle cerebral arteries, basilar artery, and posterior cerebral arteries were the most frequent vessels involved. For nine of them, imaging demonstrated ischemic or hemorrhagic complications. CONCLUSION: Cerebral vasculitis of medium-sized vessels seems to be one of the mechanisms at the origin of brain damage related to COVID-19.

Early Brain Imaging Shows Increased Severity of Acute Ischemic Strokes With Large Vessel Occlusion in COVID-19 Patients.

BACKGROUND AND PURPOSE: Reports are emerging regarding the association of acute ischemic strokes with large vessel occlusion and coronavirus disease 2019 (COVID-19). While a higher severity of these patients could be expected from the addition of both respiratory and neurological injury, COVID-19 patients with strokes can present with mild or none respiratory symptoms. We aimed to compare anterior circulation large vessel occlusion strokes severity between patients with and without COVID-19. METHODS: We performed a comparative cohort study between patients with COVID-19 who had anterior circulation large vessel occlusion and early brain imaging within 3 hours from onset, in our institution during the 6 first weeks of the COVID-19 outbreak and a control group admitted during the same calendar period in 2019. RESULTS: Twelve COVID-19 patients with anterior circulation large vessel occlusion and early brain imaging were included during the study period and compared with 34 control patients with anterior circulation large vessel occlusion and early brain imaging in 2019. Patients in the COVID-19 group were younger (P=0.032) and had a history of diabetes mellitus more frequently (P=0.039). Patients did not significantly differ on initial National Institutes of Health Stroke Scale nor time from onset to imaging (P=0.18 and P=0.6, respectively). Patients with COVID-19 had more severe strokes than patients without COVID-19, with a significantly lower clot burden score (median: 6.5 versus 8, P=0.016), higher rate of multivessel occlusion (50% versus 8.8%, P=0.005), lower DWI-ASPECTS (Diffusion-Weighted Imaging-Alberta Stroke Program Early CT Scores; median: 5 versus 8, P=0.006), and higher infarct core volume (median: 58 versus 6 mL, P=0.004). Successful recanalization rate was similar in both groups (P=0.767). In-hospital mortality was higher in the COVID-19 patients' group (41.7% versus 11.8%, P=0.025). CONCLUSIONS: Early brain imaging showed higher severity large vessel occlusion strokes in patients with COVID-19. Given the massive number of infected patients, concerns should be raised about the coming neurovascular impact of the pandemic worldwide.

Critical illness-associated cerebral microbleeds in COVID-19.

We are reporting the imaging findings of the rare entity of critical illness-associated cerebral microbleeds in a COVID-19-positive 66-year-old woman with hypoxic respiratory failure, who was eventually intubated and ventilated. Multiple scattered cerebral microhaemorrhages diffusely distributed in the juxtacortical white matter and internal capsule region, sparing the deep and periventricular white matter, basal ganglia, thalami and cortex were seen, which is a unique imaging finding in critically ill patients with respiratory failure and hypoxemia requiring mechanical ventilation. The mechanism underlying these microhaemorrhages relates to the endpoint of critical illness, rather than a specific underlying disease.