Assessment of the Corticospinal Tract Profile in Pure Lower Motor Neuron Disease: A Diffusion Tensor Imaging Study.

AIM: The aim of this study was to evaluate the corticospinal tract (CST) diffusion profile in pure lower motor neuron disease (pLMND) patients who at baseline did not show any clinical or electrophysiological involvement of upper motor neurons (UMN), and in amyotrophic lateral sclerosis (ALS) patients. MATERIALS AND METHODS: Fifteen ALS patients with delayed central motor conduction time (CMCT) and 14 pLMND patients with normal CMCT were enrolled together with 15 healthy controls. Fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) maps were obtained. The tract profile of CST was reconstructed with the automated fiber quantification tool and its diffusion properties were quantified voxel-by-voxel and then compared pairwise between groups. Moreover, a random forest (RF) classifier was trained to evaluate the ability of CST diffusion metrics in distinguishing pairwise the groups from the controls. RESULTS: ALS patients presented wide microstructural abnormalities in the entire CST as assessed by FA decrease and RD increase while pLMND patients showed focal FA decrease and a larger AD increase in the cerebral peduncle and posterior limb of the internal capsule in comparison with controls. RF revealed that diffusion tensor imaging (DTI) metrics accurately distinguished ALS patients and pLMND patients from controls (96.67 and 95.71% accuracy, respectively). CONCLUSIONS: Our study demonstrates that the CST was impaired in both ALS and pLMND patients, thus suggesting that DTI metrics are a reliable tool in detecting subtle changes of UMN in pLMND patients, also in the absence of clinical and CMCT abnormalities.

The corticospinal tract profile in amyotrophic lateral sclerosis.

This work evaluates the potential in diagnostic application of a new advanced neuroimaging method, which delineates the profile of tissue properties along the corticospinal tract (CST) in amyotrophic lateral sclerosis (ALS), by means of diffusion tensor imaging (DTI). Twenty-four ALS patients and twenty-four demographically matched healthy subjects were enrolled in this study. The Automated Fiber Quantification (AFQ), a tool for the automatic reconstruction of white matter tract profiles, based on a deterministic tractography algorithm to automatically identify the CST and quantify its diffusion properties, was used. At a group level, the highest non-overlapping DTI-related differences were detected in the cerebral peduncle, posterior limb of the internal capsule, and primary motor cortex. Fractional anisotropy (FA) decrease and mean diffusivity (MD) and radial diffusivity (RD) increases were detected when comparing ALS patients to controls. The machine learning approach used to assess the clinical utility of this DTI tool revealed that, by combining all DTI metrics measured along tract between the cerebral peduncle and the corona radiata, a mean 5-fold cross validation accuracy of 80% was reached in discriminating ALS from controls. Our study provides a useful new neuroimaging tool to characterize ALS-related neurodegenerative processes by means of CST profile. We demonstrated that specific microstructural changes in the upper part of the brainstem might be considered as a valid biomarker. With further validations this method has the potential to be considered a promising step toward the diagnostic utility of DTI measures in ALS. Hum Brain Mapp 38:727-739, 2017. © 2016 Wiley Periodicals, Inc.

MR parkinsonism index predicts vertical supranuclear gaze palsy in patients with PSP-parkinsonism.

OBJECTIVE: To identify a biomarker for predicting the appearance of vertical supranuclear gaze palsy (VSGP) in patients affected by progressive supranuclear palsy-parkinsonism (PSP-P). METHODS: Twenty-four patients with PSP-P were enrolled in the current study. Patients were clinically followed up every 6 months until the appearance of VSGP or the end of the follow-up (4 years). Participants underwent MRI at baseline and at the end of follow-up. Magnetic resonance parkinsonism index (MRPI), an imaging measure useful for diagnosing PSP, was calculated. RESULTS: Twenty-one patients with PSP-P completed follow-up, and 3 patients dropped out. Eleven of 21 patients with PSP-P developed VSGP after a mean follow-up period of 28.5 months (range 6-48 months), while the remaining 10 patients with PSP-P did not develop VSGP during the 4-year follow-up period. At baseline, patients with PSP-P who later developed VSGP had MRPI values significantly higher than those of patients not developing VSGP without overlapping values between the 2 groups. MRPI showed a higher accuracy (100%) in predicting VSGP than vertical ocular slowness (accuracy 33.3%) or postural instability with or without vertical ocular slowness (accuracy 71.4% and 42.9%, respectively). CONCLUSIONS: Our study demonstrates that MRPI accurately predicted, on an individual basis, the appearance of VSGP in patients with PSP-P, thus confirming clinical diagnosis in vivo.

Polymorphism of the multidrug resistance 1 gene MDR1/ABCB1 C3435T and response to antiepileptic drug treatment in temporal lobe epilepsy.

PURPOSE: A synonymous C to T variant at position 3435 (c.3435C>T) is one common polymorphism of the multidrug resistant 1 (MDR1) gene, which encodes the major transmembrane efflux transporter P-glycoprotein. It has been suggested that this polymorphism, and more specifically the 3435CC genotype, may be associated with the response to antiepileptic drug treatment. Here we wished to examine the role of such a candidate variant in a cohort of 175 patients (98 women and 76 men; mean ± SD age: 47.90 ± 17.64) with temporal lobe epilepsy (TLE). METHODS: Patients were classified according to whether they had drug-responsive (n=134) or drug-resistant (n=41) epilepsy. We also enrolled 175 healthy controls (93 women and 82 men; mean ± SD age: 72.5 ± 6.8), matched for sex and ethnicity. RESULTS: Patients and controls were genotyped for detection of the 3435C>T polymorphism, but the analysis showed no significant association between the CC genotype and the risk of drug-resistant epilepsy. CONCLUSION: These findings rule out the MDR1 c.3435C>T polymorphism having a major role or increasing the risk of drug-resistance suggesting a revision is required to determine the contribution of this polymorphism in predicting drug response in epilepsy.

Rating scale for psychogenic nonepileptic seizures: scale development and clinimetric testing.

Our aim was to develop a clinimetric scale evaluating motor phenomena, associated features, and severity of psychogenic nonepileptic seizures (PNES). Sixty video/EEG-recorded PNES induced by suggestion maneuvers were evaluated. We examined the relationship between results from this scale and results from the Clinical Global Impression (CGI) scale to validate this technique. Interrater reliabilities of the PNES scale for three raters were analyzed using the AC1 statistic, Kendall's coefficient of concordance (KCC), and intraclass correlation coefficients (ICCs). The relationship between the CGI and PNES scales was evaluated with Spearman correlations. The AC1 statistic demonstrated good interrater reliability for each phenomenon analyzed (tremor/oscillation, tonic; clonic/jerking, hypermotor/agitation, atonic/akinetic, automatisms, associated features). KCC and the ICC showed moderate interrater agreement for phenomenology, associated phenomena, and total PNES scores. Spearman's correlation of mean CGI score with mean total PNES score was 0.69 (P<0.001). The scale described here accurately evaluates the phenomenology of PNES and could be used to assess and compare subgroups of patients with PNES.

Association study between four polymorphisms in the HFE, TF and TFR genes and Parkinson's disease in southern Italy.

Iron overload may lead to neurodegenerative disorders such as Parkinson's disease (PD) and alterations of iron-related genes might be involved in the pathogenesis of this disease. The gene of haemochromatosis (HFE) encodes the HFE protein which interacts with the transferrin receptor (TFR), lowering its affinity for iron-bound transferrin (TF). We examined four known polymorphisms, C282Y and H63D in the HFE gene, G258S in the TF gene and S82G in the TFR gene, in 181 sporadic PD patients and 180 controls from Southern Italy to investigate their possible role in susceptibility to PD. No significant differences were found in genotype and allele frequencies between PD and controls for all the polymorphisms studied, suggesting that these variants do not contribute significantly to the risk of PD.

Usefulness of a morning routine EEG recording in patients with juvenile myoclonic epilepsy.

OBJECTIVE: To evaluate if a standard awake EEG recording in the morning is superior to afternoon awake EEG session in detecting generalized epileptiform discharges (GEDs) in patients with juvenile myoclonic epilepsy (JME). METHODS: The study group included 29 consecutive patients (23 women; mean age 22.3+/-6.3 years; age at onset of JME 15.4+/-3.4 years) with JME. Out of 29 patients 5 were untreated, 9 patients were treated with valproate, 8 with lamotrigine, 6 with levetiracetam and 1 patient with valproate plus phenobarbital. Two routine consecutive interictal EEG recordings were performed at 9a.m. and at 3p.m., respectively, while the subject was awake, on the same day after a a regular nocturnal sleep at own home. RESULTS: The morning EEG recording showed GEDs (i.e., generalized polispike and waves, photoparoxysmal response, or both). in 20/29 patients. In 15 of these 20 patients, the afternoon recording was normal and this difference was statistically significant (p < or = 0.001). Moreover, there was a striking reduction of GEDs in three of the remaining five patients. Nine/29 patients had both morning and afternoon EEG recording normal. CONCLUSIONS: The results of this study have illustrated a significant greater rate of detection of generalized epileptiform abnormalities by performing standard awake EEG in the morning in comparison with an afternoon session.

Movement time and aging: a normative study in healthy subjects with the "Movement Time Analyzer".

BACKGROUND AND AIMS: Parkinson's disease (PD) is one of the most frequent neurodegenerative disorders characterized by bradykinesia, tremor at rest, and rigidity. Movement Time (MT) has been investigated in PD to evaluate bradykinesia and its levodopa-induced modifications. The Movement Time Analyzer (MTA) is a simple, objective and reliable instrument to study MT, but no normative study has been reported to date. METHODS: In a sample of normal subjects (n = 68), we studied MT detected by MTA in order to assess normative values, so that the MTA could be used to evaluate patients with PD in daily clinical practice. RESULTS: In normal subjects, MT progressively increased with aging, and was slower on the non-dominant side than on the dominant side. No differences were found between men or women. CONCLUSION: Our data provide further information about normative values on MT detected by MTA, and indicate that age and handedness are the main variables influencing motor task performance.