Predictive value of Tmax perfusion maps on final core in acute ischemic stroke: an observational single-center study.

PURPOSE: To assess utility of computed tomography perfusion (CTP) protocols for selection of patients with acute ischemic stroke (AIS) for reperfusive treatments and compare the diagnostic accuracy (ACC) in predicting follow-up infarction, using time-to-maximum (Tmax) maps. METHODS: We retrospectively reviewed consecutive AIS patients evaluated for reperfusive treatments at comprehensive stroke center, employing a multimodal computed tomography. To assess prognostic accuracy of CTP summary maps in predicting final infarct area (FIA) in AIS patients, we assumed the best correlation between non-viable tissue (NVT) and FIA in early and fully recanalized patients and/or in patients with favorable clinical response (FCR). On the other hand, the tissue at risk (TAR) should better correlate with FIA in untreated patients and in treatment failure. RESULTS: We enrolled 158 patients, for which CTP maps with Tmax thresholds of 9.5 s and 16 s, presented sensitivity of 82.5%, specificity of 74.6%, and ACC of 75.9%. In patients selected for perfusion deficit in anterior circulation territory, CTP-Tmax > 16 s has proven relatively reliable to identify NVT in FCR patients, with a tendency to overestimate NVT. Similarly, CTP-Tmax > 9.5 s was reliable for TAR, but it was overestimated comparing to FIA, in patients with unfavorable outcomes. CONCLUSIONS: In our experience, Tmax thresholds have proven sufficiently reliable to identify global hypoperfusion, with tendency to overestimate both NVT and TAR, not yielding satisfactory differentiation between true penumbra and benign oligoemia. In particular, the overestimation of NVT could have serious consequences in not selecting potential candidates for a reperfusion treatment.

Encephalopathy in COVID-19 Presenting With Acute Aphasia Mimicking Stroke.

Introduction: Neurological manifestations are emerging as relatively frequent complications of corona virus disease 2019 (COVID-19), including stroke and encephalopathy. Clinical characteristics of the latter are heterogeneous and not yet fully elucidated, while the pathogenesis appears related to neuroinflammation in a subset of patients. Case: A middle-aged man presented with acute language disturbance at the emergency department. Examination revealed expressive aphasia, mild ideomotor slowing, and severe hypocapnic hypoxemia. Multimodal CT assessment and electroencephalogram (EEG) did not reveal any abnormalities. COVID-19 was diagnosed based on chest CT findings and positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcription PCR (RT-PCR) on nasopharyngeal swab. The following day, neurological symptoms progressed to agitated delirium and respiratory status worsened, requiring admission to the ICU and mechanical ventilation. Brain MRI and cerebrospinal fluid (CSF) studies were unremarkable. RT-PCR for SARS-CoV-2 on CSF was negative. He received supportive treatment and intravenous low-dose steroids. His neurological and respiratory status resolved completely within 2 weeks. Conclusions: We report a patient with reversible COVID-19-related encephalopathy presenting as acute aphasia, mimicking stroke or status epilepticus, eventually evolving into delirium. Although large-vessel stroke is frequently encountered in COVID-19, our case suggests that focal neurological deficits may occur as the earliest feature of encephalopathy. Neurological status reversibility and the absence of abnormalities on brain MRI are consistent with a functional rather than a structural neuronal network impairment.

Diagnostic and Prognostic Value of Conventional Brain MRI in the Clinical Work-Up of Patients with Amyotrophic Lateral Sclerosis.

Clinical signs of upper motor neuron (UMN) involvement are important in the diagnosis of amyotrophic lateral sclerosis (ALS) though are often difficult to analyze. Many studies using both qualitative and quantitative evaluations have reported abnormal Magnetic Resonance Imaging (MRI) findings at the level of the pyramidal pathway in patients with ALS. Although the most interesting results were obtained by quantitative studies using advanced MR techniques, the qualitative evaluation of MRI images remains the most-used in clinical practice. We evaluated the diagnostic and prognostic contribution of conventional 3T-MRI in the clinical work-up of ALS patients. Two neuroradiologists retrospectively assessed 3T-MRI data of 93 ALS patients and 89 controls. The features of interest were corticospinal tract (CST) T2/FLAIR hyperintensity, motor cortex (MC) T2*/SWI hypointensity, and selective MC atrophy. All MRI features were significantly more prevalent in ALS patients than in controls. The simultaneous presence of CST FLAIR hyperintensity and MC SWI hypointensity was associated with the highest diagnostic accuracy (sensitivity: 70%; specificity: 81%; positive predictive value, PPV: 90%; negative predictive value, NPV: 51%; accuracy: 73%) and a shorter survival (HR: 6.56, p = 0.002). Conventional 3T-MRI can be a feasible tool to detect specific qualitative changes based on UMN involvement and to support clinical diagnosis of ALS. Importantly, CST FLAIR hyperintensity and MC SWI hypointensity are predictors of shorter survival in ALS patients.

Broadening the Spectrum of Adulthood X-Linked Adrenoleukodystrophy: A Report of Two Atypical Cases.

X-linked adrenoleukodystrophy (x-ALD) is a rare genetic disorder caused by a mutation in the ABCD1 gene, which encodes for a peroxisomal very long chain fatty acid transporter. Clinically, x-ALD can present a wide spectrum of different phenotypes: asymptomatic carriers, Addison only, cerebral x-ALD, and myelopathy with/without evidence of peripheral axonopathy (Adrenomyeloneuropathy). We report on two cases of adult x-ALD, with atypical phenotypes: (Case 1) A 37-years-old male with a 2-years-long history of spastic paraparesis, urinary urgency, and subclinical adrenocortical insufficiency. As an atypical finding, the MRI showed multiple congenital brain development defects. (Case 2) A 63-years-old male with a previous diagnosis of Addison disease, with a 6-years-long history of spastic paraparesis. Two years later, he complained of severe and disabling burning pain in his feet. A nerve conduction study was normal, but a skin biopsy revealed autonomic and somatic small fiber neuropathy. In both cases, genetic testing disclosed hemizygous mutation in ABCD1 associated with x-ALD: c.1394-2A > G and p.(Thr254Met), respectively. While case 1 supports the key role of peroxisome functions in brain development, case 2 points to a possible selective and clinically relevant peripheral small fiber degeneration in x-ALD myelopathy.

Temporo-mesial extraventricular neurocytoma and cortical dysplasia in focal temporal lobe epilepsy.

We describe a 17-year-old boy with a left extraventricular temporo-mesial neurocytoma associated with cortical dysplasia causing focal pharmacoresistant temporal lobe epilepsy. He presented with a long history of medically refractory, temporal complex partial seizures. MRI showed a left temporo-mesial lesion suspect to be a low-grade tumor. Based on the pre-operative non-invasive neurophysiological studies, the patient underwent a left tailored temporal antero-mesial resection. Histopathological examination showed an extraventricular neurocytoma associated with architectural dysplasia (Type 1a) of the temporal pole. The patient was seizure-free at 2 years follow-up. Extraventricular neurocytomas must be considered in the differential diagnosis of the plethora of low-grade tumors associated with focal epilepsy that typically involve the temporal lobe, and are frequently associated with focal cortical dysplasia.

Essential tremor is not associated with alpha-synuclein gene haplotypes.

A specific allele of the NACP-Rep1 polymorphism within the alpha-synuclein promoter was found to be associated both with Parkinson's disease and essential tremor. We repeated the association study on a large series of Italian patients with essential tremor using a panel of polymorphisms within the alpha-synuclein gene. Our results did not confirm the association reported previously and failed to identify a alpha-synuclein specific haplotype as susceptibility factor for essential tremor.