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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.

Background Idiopathic normal pressure hydrocephalus (iNPH) is characterized by the classic clinical triad of gait, cognitive, and urinary dysfunction, albeit incomplete in a relevant proportion of patients. The clinical findings and evolution of these symptoms have been variably defined in the literature. Objectives To evaluate how the phenomenology has been defined, assessed, and reported, we performed a critical review of the existing literature discussing the phenomenology of iNPH. The review also identified the instrumental tests most frequently used and the evolution of clinical and radiologic findings. Methods The review was divided into 3 sections based on gait, cognitive, and urinary dysfunction. Each section performed a literature search using the terms “idiopathic normal pressure hydrocephalus” (iNPH), with additional search terms used by each section separately. The number of articles screened, duplicates, those meeting the inclusion criteria, and the number of articles excluded were recorded. Findings were subsequently tallied and analyzed. Results A total of 1716 articles with the aforementioned search criteria were identified by the 3 groups. A total of 81 full‐text articles were reviewed after the elimination of duplicates, articles that did not discuss phenomenological findings or instrumental testing of participants with iNPH prior to surgery, and articles with fewer than 10 participants. Conclusions “Wide‐based gait” was the most common gait dysfunction identified. Cognitive testing varied significantly across articles, and ultimately a specific cognitive profile was not identified. Urodynamic testing found detrusor overactivity and “overactive bladder” as the most common symptom of urinary dysfunction.

The “interlimb transfer” phenomenon consists of improved performance of the trained and untrained contralateral limbs after unilateral motor practice. We here assessed whether a visuomotor learning task can be transferred from one hemisphere to the other, whether this occurs symmetrically, and the cortical neurophysiological correlates of this phenomenon, focusing on interhemispheric connectivity measures. We enrolled 33 healthy subjects (age range: 24–73 years). Participants underwent two randomized sessions, which investigated the transfer from the dominant to the nondominant hand and vice versa. Measures of cortical and intracortical excitability and interhemispheric inhibition were assessed through transcranial magnetic stimulation before and after a visuomotor task. The execution of the visuomotor task led to an improvement in motor performance with the dominant and nondominant hands and induced a decrease in intracortical inhibition in the trained hemisphere. Participants were also able to transfer the visuomotor learned skill. The interlimb transfer, however, only occurred from the dominant to the nondominant hand and positively correlated with individual learning-related changes in interhemispheric inhibition. We here demonstrated that the “interlimb transfer” of a visuomotor task occurs asymmetrically and relates to the modulation of specific inhibitory interhemispheric connections. The study results have pathophysiological, clinical, and neuro-rehabilitative implications.

BackgroundGait analysis objectively quantifies gait impairment in idiopathic normal pressure hydrocephalus (iNPH), may improve diagnosis and evaluation for surgical candidacy.ObjectivesThis meta‐analysis aims to understand which objective gait parameters improve after tap‐test (TT) and CSF shunt surgery (CSS), also comparing responders (R) with non‐responders (NR) and to assess if gait restores within the range of healthy controls after procedures.MethodsStudies enrolling iNPH with at least one instrumented gait measure were selected. Three time points of gait assessment were defined: PRE, POST‐TT, and POST‐CSS. Gait velocity, cadence, step length, stride length, and double limb support time were evaluated. Patients were categorized based on responsiveness to CSF diversion procedures.ResultsSeventeen studies including 527 patients were selected. iNPH improved significantly in almost all gait parameters POST‐TT, and to a greater extent POST‐CSS. Gait parameters consistently discriminated iNPH from healthy controls. Despite the aforementioned improvements, iNPH's gait did not completely normalize after CSF diversion procedures. Meta‐regression analysis also revealed that TT's effect on gait velocity plateaus after 24‐48 hours and returns to baseline in 90‐100 hours.ConclusionsGait analysis is a reliable quantitative instrument to assess gait impairment in iNPH, demarking a net differentiation from healthy controls, according to the notion that the iNPH CSF dynamic alteration also leads to an irreversible damage. Specific gait parameters improve among TT‐R, providing an opportunity to select patients that will respond to CSS. Future studies validating a standardized reporting method including criteria of responsiveness, specific gait parameters, and timeframe of assessment are needed.This article is protected by copyright. All rights reserved.