actor associated with outcomes and mortality in COVID-19 patients includes cardiovascular and cerebrovascular comorbidities but the underlying mechanisms are still hypothetical 1. We report the case ...of a 73-year-old patient who developed within a week after the onset of respiratory symptoms related to SARS-CoV2 infection, an acute ischemic stroke (AIS) complicating a large floating thrombus within the common carotid artery. The patient has no specific past medical history, no treatment and no vascular risk factors. He presented at the emergency department on March 25th for the onset of fever and dry cough. Clinical evaluation was reassuring and the patient was discharged home. He was readmitted 7 days later for the acute onset of aphasia and right hemiparesis evolving for 9 hours. On admission, the patient was in respiratory distress, and neurological examination revealed a left middle cerebral artery (MCA) syndrome with a NIH stroke scale (NIHSS) of 10. Chest CT showed ground glass opacities typically reported in SARS-CoV2 infection, which was subsequently confirmed by real-time reverse transcriptase–polymerase chain reaction assay on a nasopharyngeal swab sample. Brain Computer Tomography (CT), CT angiography (CTA) and CT perfusion, performed on a 64-channel scanner (Optima, General Electric, USA), showed subtle cortical left frontal hypoattenuation with more extended surrounding hypoperfusion and distal occlusion of branch. CT perfusion was acquired before CTA, and both were performed using, for each, a 40 cc-bolus of iodine contrast injected at a 5 cc/sec rate (iobitridol 350, Guerbet, France), pushed by 40 cc of physiological serum. Cervical CTA also revealed a large intraluminal floating thrombus appended to a hypoattenuated non-stenosing plaque of the left common carotid artery wall. Dedicated wall imaging with 3 T MRI (Skyra, Siemens, Germany) and Doppler ultrasoonography confirmed the diagnosis of a large thrombus adherent to a thin atheromatous plaque. Of note, those examination disclosed no ulceration, plaque hemorrhage or circumferential gadolinium enhancement of the wall potentially suggestive of arteritis. Diffusion-Weighted Imaging performed 2 days later confirmed the diagnosis of multiple AIS with foci of hyperintensity scattered within left carotid territory.
The purpose of this study is to present the authors' medium-term results, with special emphasis on complications, occlusion rate of the aneurysm sac (digital subtraction angiography DSA and MRI), and ...the fate of cortical branches and perforating arteries covered ("jailed") by the flow diverter (FD) stent.
Between January 2010 and September 2017, 29 patients (14 female) with 30 aneurysms were treated with an FD stent. Twenty-one aneurysms were at the middle cerebral artery bifurcation, 8 were in the anterior communicating artery region, and 1 was a pericallosal artery bifurcation. Thirty-five cortical branches were covered. A single FD stent was used in all patients. Symptomatic and asymptomatic periprocedural and delayed complications were reported. DSA and MRI controls were analyzed to evaluate modification of the aneurysm sac and jailed branches.
Permanent morbidity was 3.4% (1/29), due to a jailed branch occlusion, with a modified Rankin Scale (mRS) score of 2 at the last follow-up. Mortality and permanent complication with poor prognosis (mRS score > 2) rates were 0%. The mean follow-up time for DSA and MRI (mean ± SD) was 21 ± 14.5 months (range 3-66 months) and 19 ± 16 months (range 3-41 months), respectively. The mean time to aneurysm sac occlusion (available for 24 patients), including stable remodeling, was 11.8 ± 6 months (median 13, range 3-27 months). The overall occlusion rate was 82.1% (23/28), and it was 91.7% (22/24) in the group of patients with at least 2 DSA control sequences. One recanalization occurred at 41 months posttreatment. At the time of publication, at the latest follow-up, 7 (20%) of 35 covered branches were occluded, 18 (51.4%) showed a decreased caliber, and the remaining 10 (28.5%) were unchanged. MRI T2-weighted sequences showed complete sac reabsorption in 7/29 aneurysms (24.1%), and the remaining lesions were either smaller (55.2%) or unchanged (17.2%). MRI revealed asymptomatic and symptomatic ischemic events in perforator territories in 7/28 (25%) and 4/28 (14.3%) patients, respectively, which were reversible within 24 hours.
Flow diversion of bifurcation aneurysms is feasible, with low rates of permanent morbidity and mortality and high occlusion rates; however, recurrence may occur. Caliber reduction and asymptomatic occlusion of covered cortical branches as well as silent perforator stroke are common. Ischemic complications may occur with no identified predictable factors. MRI controls should be required in all patients to evaluate silent ischemic lesions and aneurysm sac reabsorption over time.
Computed tomography (CT) and magnetic resonance (MR) imaging reliably demonstrate typical features of vestibular schwannomas or meningiomas in the vast majority of mass lesions in the ...cerebellopontine angle (CPA). However, a large variety of unusual lesions can also be encountered in the CPA. Covering the entire spectrum of lesions potentially found in the CPA, these articles explain the pertinent neuroimaging features that radiologists need to know to make clinically relevant diagnoses in these cases, including data from diffusion and perfusion-weighted imaging or MR spectroscopy, when available. A diagnostic algorithm based on the lesion's site of origin, shape and margins, density, signal intensity and contrast material uptake is also proposed. Part 1 describes the different enhancing extra-axial CPA masses primarily arising from the cerebellopontine cistern and its contents, including vestibular and non-vestibular schwannomas, meningioma, metastasis, aneurysm, tuberculosis and other miscellaneous meningeal lesions.
Although perfusion magnetic resonance imaging (MRI) is widely used to identify pseudoprogression, this advanced technique lacks clinical reliability. Our aim was to develop a parameter assessing the ...hypervascularized fraction of glioblastomas based on volume analysis of dynamic susceptibility contrast-enhanced MRI and evaluate its performance in the diagnosis of pseudoprogression. Out of 25 patients, 11 (44%) were classified with pseudoprogression and 14 (56%) with true progression based on the Response Assessement in Neuro-Oncology criteria. rCBVmax was lower for pseudoprogression (3.4 vs. 7.6; p = 0.033) on early follow-up MRI. %rCBV>2, was lower for pseudoprogression on both initial (57.5% vs. 71.3%; p = 0.033) and early follow-up MRIs (22.1% vs. 51.8%; p = 0.0006). On early follow-up MRI, %rCBV>2 had the largest area under the curve for the diagnosis of pseudoprogression: 0.909 0.725-0.986. The fraction of hypervascularization of glioblastomas as assessed by %rCBV>2 was lower in tumours that subsequently developed pseudoprogression both on the initial and early follow-up MRIs. This fractional parameter may help identify pseudoprogression with greater accuracy than rCBVmax.
Late-onset neutropenia after rituximab therapy (LONART) is defined as a fall in the absolute neutrophil count below 500/mm3 at least 3 weeks after rituximab infusion, in the absence of any other ...explanation. LONART is rare during dysimmune conditions but can be life-threatening. We report on two patients with LONART and associated neurological relapse occurring in myelin oligodendrocyte glycoprotein (MOG)-antibody spectrum disorders. Rituximab was reintroduced in one patient, while the second patient was switched to tocilizumab. LONART can occur during anti-MOG spectrum disorders. Neurologists should be aware of this rare and treatable complication. Regular monitoring of blood cell counts is needed, and patients should be informed of the need to consult their physician if symptoms of infection appear.
To retrospectively review the brain magnetic resonance (MR) imaging and computed tomographic (CT) findings in patients with Erdheim-Chester disease (ECD).
The ethics committee required neither ...institutional review board approval nor informed patient consent for retrospective analyses of the patients' medical records and imaging data. The patients' medical files were retrospectively reviewed in accordance with human subject research protocols. Three neuroradiologists in consensus analyzed the signal intensity, location, size, number, and gadolinium uptake of lesions detected on brain MR images obtained in 33 patients with biopsy-proved ECD.
Thirty patients had intracranial, facial bone, and/or orbital involvement, and three had normal neurologic imaging findings. The hypothalamic-pituitary axis was involved in 16 (53%) of the 30 patients, with six (20%) cases of micronodular or nodular masses of the infundibular stalk. Meningeal lesions were observed in seven (23%) patients. Three (10%) patients had bilateral symmetric T2 high signal intensity in the dentate nucleus areas, and five (17%) had multiple intraaxial enhancing masses. Striking intracranial periarterial infiltration was observed in three (10%) patients. Another patient (3%) had a lesion in the lumen of the superior sagittal sinus. Nine (30%) patients had orbital involvement. Twenty-four (80%) patients had osteosclerosis of the facial and/or skull bones. At least two anatomic sites were involved in two-thirds (n = 20) of the patients. Osteosclerosis of the facial bones associated with orbital masses and either meningeal or infundibular stalk masses was seen in eight (27%) patients.
Lesions of the brain, meninges, facial bones, and orbits are frequently observed and should be systematically sought on the brain MR and CT images obtained in patients with ECD, even if these patients are asymptomatic. Careful attention should be directed to the periarterial environment.
Responses of GH-secreting adenomas to multimodal management of acromegaly vary widely between patients. Understanding the behavioral patterns of GH-secreting adenomas by identifying factors ...predictive of their evolution is a research priority. The aim of this study was to clarify the relationship between the T2-weighted adenoma signal on diagnostic magnetic resonance imaging (MRI) in acromegaly and clinical and biological features at diagnosis. An international, multicenter, retrospective analysis was performed using a large population of 297 acromegalic patients recently diagnosed with available diagnostic MRI evaluations. The study was conducted at ten endocrine tertiary referral centers. Clinical and biochemical characteristics, and MRI signal findings were evaluated. T2-hypointense adenomas represented 52.9% of the series, were smaller than their T2-hyperintense and isointense counterparts (P<0.0001), were associated with higher IGF1 levels (P=0.0001), invaded the cavernous sinus less frequently (P=0.0002), and rarely caused optic chiasm compression (P<0.0001). Acromegalic men tended to be younger at diagnosis than women (P=0.067) and presented higher IGF1 values (P=0.01). Although in total, adenomas had a predominantly inferior extension in 45.8% of cases, in men this was more frequent (P<0.0001), whereas in women optic chiasm compression of macroadenomas occurred more often (P=0.0067). Most adenomas (45.1%) measured between 11 and 20 mm in maximal diameter and bigger adenomas were diagnosed at younger ages (P=0.0001). The T2-weighted signal differentiates GH-secreting adenomas into subgroups with particular behaviors. This raises the question of whether the T2-weighted signal could represent a factor in the classification of acromegalic patients in future studies.
Background and Purpose- Our goal was to evaluate whether the presence of a low signal intensity known as susceptibility vessel sign (SVS) on T2*-gradient echo imaging sequence was predictive of ...arterial recanalization and the early clinical improvement after mechanical thrombectomy. Methods- This observational study was based on a prospective database of acute ischemic strokes treated by mechanical thrombectomy. Inclusion criteria were patients with acute anterior ischemic stroke, diagnosed by magnetic resonance imaging, including a T2*-gradient echo imaging sequence, and treated by mechanical thrombectomy. Two independent readers assessed the presence of an SVS. Successful recanalization was defined as a Thrombolysis in Cerebral Infarction score of 2b-3 after mechanical thrombectomy. Early clinical improvement was estimated by the difference between the baseline National Institutes of Health Stroke Scale and the National Institutes of Health Stroke Scale on day 1 after treatment Results- The SVS was detected in 137 (76%) out of 180 patients. The kappa interrater agreement was 0.71 with a 95% CI of 0.59 to 0.82. Successful recanalization was associated with an SVS+ with odds ratio, 2.48; 95% CI, 1.05-5.74; P=0.03. The early clinical improvement was better in patients with an SVS+ (median, -6; interquartile range, -11 to 0) compared with SVS- patients (median, -1; interquartile range, -10 to 3) with P=0.01. Conclusions- The visualization of SVS is a reliable and easily accessible predictive factor of recanalization success and early clinical improvement.
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