Diagn Microbiol Infect Dis
November 2019
Objective: To assess the predictive value of JC virus (JCV) PCR in cerebrospinal fluid (CSF) in the diagnosis of progressive multifocal leukoencephalopathy (PML).
Methods: We conducted a retrospective database query to identify patients with positive CSF JCV PCR. Clinical features, final diagnosis and quantitative PCR results were obtained.
Objective: The motor unit size index (MUSIX) is incorporated into the motor unit number index (MUNIX). Our objective was to assess the intra-/inter-rater reliability of MUSIX in healthy volunteers across single subject "round robin" and multi-centre settings.
Methods: Data were obtained from (i) a round-robin assessment in which 12 raters (6 with prior experience and 6 without) assessed six muscles (abductor pollicis brevis, abductor digiti minimi, biceps brachii, tibialis anterior, extensor digitorum brevis and abductor hallucis) and (ii) a multi-centre study with 6 centres studying the same muscles in 66 healthy volunteers.
Simultaneous registration of scalp electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) is considered an attractive approach for studying brain function non-invasively. It combines the better spatial resolution of fMRI with the better temporal resolution of EEG, but comes at the cost of increased measurement artifact and the accompanying artifact preprocessing. This paper presents a study of the residual signal quality based on temporal signal to noise ratio (TSNR) for fMRI and fast Fourier transform (FFT) for EEG, after optimized conventional signal preprocessing.
View Article and Find Full Text PDFTime-varying connectivity analysis based on sources reconstructed using inverse modeling of electroencephalographic (EEG) data is important to understand the dynamic behaviour of the brain. We simulated cortical data from a visual spatial attention network with a time-varying connectivity structure, and then simulated the propagation to the scalp to obtain EEG data. Distributed EEG source modeling using sLORETA was applied.
View Article and Find Full Text PDFNeurol Neuroimmunol Neuroinflamm
March 2018
Amyotroph Lateral Scler Frontotemporal Degener
August 2017
Objective: To assess the added prognostic value of the aggregated clinical and electrodiagnostic data, which define a given diagnostic category according to the Awaji or revised El Escorial criteria at time of diagnosis in patients with amyotrophic lateral sclerosis (ALS).
Methods: Clinical signs and electrodiagnostic test results were collected at time of diagnosis in 396 patients with ALS between January 2009 and January 2016. Significant predictors of prognosis were identified using a univariate model, and later combined in a multivariate Cox regression model.
Spatial-attentional reorienting and selection between competing stimuli are two distinct attentional processes of clinical and fundamental relevance. In the past, reorienting has been mainly associated with inferior parietal cortex. In a patient with a subdural grid covering the upper and lower bank of the left anterior and middle intraparietal sulcus (IPS) and the superior parietal lobule (SPL), we examined the involvement of superior parietal cortex using a hybrid spatial cueing paradigm identical to that previously applied in stroke and in healthy controls.
View Article and Find Full Text PDFFor the diagnosis of electrographic seizures or status epilepticus, we reduced the number of EEG-electrodes to make urgent EEG monitoring more feasible. Unlike the current existing research, with mixed results, we studied a specific population with postanoxic brain damage, expecting a higher yield of detection of ictal EEG patterns. In a population treated with therapeutic hypothermia post-cardiac arrest, the initial EEGs were reformatted in a longitudinal, a hairline and an 8-lead montage, and independently reviewed by two investigators.
View Article and Find Full Text PDFObjective: To determine the utility of the Awaji criteria in diagnosing amyotrophic lateral sclerosis (ALS) and to propose a novel modification so as to enhance sensitivity based on results of individual patient data (IPD).
Methods: Individual patient data were available from 8 studies comparing the diagnostic accuracy of Awaji and revised El Escorial (rEEC) criteria. The sensitivity of a novel updated Awaji criteria, incorporating a "probable-laboratory supported" category, was also tested.
Background: Motor Unit Number Index (MUNIX) is a neurophysiological measure that provides an index of the number of lower motor neurons in a muscle. Its performance across centres in healthy subjects and patients with Amyotrophic Lateral Sclerosis (ALS) has been established, but inter-rater variability between multiple raters in one single subject has not been investigated.
Objective: To assess reliability in a set of 6 muscles in a single subject among 12 examiners (6 experienced with MUNIX, 6 less experienced) and to determine variables associated with variability of measurements.
The aim of this study was to investigate the relationship between stroke lesion location and the resulting somatosensory deficit. We studied exteroceptive and proprioceptive somatosensory symptoms and stroke lesions in 38 patients with first-ever acute stroke. The Erasmus modified Nottingham Sensory Assessment was used to clinically evaluate somatosensory functioning in the arm and hand within the first week after stroke onset.
View Article and Find Full Text PDFAnnu Int Conf IEEE Eng Med Biol Soc
August 2015
Kalman filter approaches are widely applied to derive time varying effective connectivity from electroencephalographic (EEG) data. For multi-trial data, a classical Kalman filter (CKF) designed for the estimation of single trial data, can be implemented by trial-averaging the data or by averaging single trial estimates. A general linear Kalman filter (GLKF) provides an extension for multi-trial data.
View Article and Find Full Text PDFA 85 year old woman with a history of severe depression treated with mirtazapine and venlafaxine was admitted to the hospital twice after progressive deterioration of her general condition evolving to unconsciousness. Clinicians diagnosed a metabolic encephalopathy caused by a urinary tract infection which was treated appropriately. Although mirtazapine was stopped during the first hospitalization, the patient's general practitioner restarted mirtazapine four days before readmission.
View Article and Find Full Text PDFBased on a previous fMRI connectivity analysis, we previously proposed that long-distance connections between left inferior frontal sulcus and left occipitotemporal sulcus mediate access to visual short-term memory both for written words and pictures enhancing conscious perception and successful encoding in an amodal manner. Using a 64-channel event-related potential electrode system in 19 young cognitively intact volunteers, we determined the chronometry of common and input-modality specific effects of word and picture identification and subsequent memory retrieval. Stimulus durations were calibrated per subject, modality and run so as to reach a 50% positive identification report.
View Article and Find Full Text PDFObjective: Early and accurate diagnosis of amyotrophic lateral sclerosis (ALS) is important for patient care and for entry in clinical trials. Retrospective studies suggest that the use of the Awaji algorithm for the diagnosis of ALS is more sensitive for early diagnosis than the currently used revised El Escorial criteria.
Methods: We prospectively compared the revised El Escorial criteria with the Awaji algorithm in patients seen with suspected ALS at the University Hospitals Leuven between January 2008 and April 2010.
Peroxisomal biogenesis disorders typically cause severe multisystem disease and early death. We describe a child and an adult of normal intelligence with progressive ataxia, axonal motor neuropathy, and decreased vibration sense. Both patients had marked cerebellar atrophy.
View Article and Find Full Text PDFBackground And Purpose: We studied the risk of recurrent cerebrovascular events in patients who had a transient ischemic attack or ischemic stroke and who had evidence of microbleeds on MRI.
Methods: A prospective follow-up study was performed on hospitalized patients who were at least 50 years old with a transient ischemic attack or an ischemic stroke. The presence and number of microbleeds were assessed on gradient echo MRI and the presence of white matter disease on fluid-attenuated inversion recovery imaging using a semiquantitative scale.
Background And Purpose: To make informed treatment decisions, patients and physicians need to be aware of the benefits and risks of a proposed treatment. The number needed to treat (NNT) for benefit and harm are intuitive and statistically valid measures to describe a treatment effect. The aim of this study is to calculate treatment time-specific NNT estimates based on shifts over the entire spectrum of clinically relevant functional outcomes.
View Article and Find Full Text PDFIntroduction: Intensive insulin therapy (IIT) reduced the incidence of critical illness polyneuropathy and/or myopathy (CIP/CIM) and the need for prolonged mechanical ventilation (MV >or= 14 days) in two randomised controlled trials (RCTs) on the effect of IIT in a surgical intensive care unit (SICU) and medical intensive care unit (MICU). In the present study, we investigated whether these effects are also present in daily clinical practice when IIT is implemented outside of a study protocol.
Methods: We retrospectively studied electrophysiological data from patients in the SICU and MICU, performed because of clinical weakness and/or weaning failure, before and after routine implementation of IIT.