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Radiomics is emerging as a promising and useful tool in cardiac magnetic resonance (CMR) imaging applications. Accordingly, the purpose of this study was to investigate, for the first time, the effect of image preprocessing and filtering on radiomic features estimation from quantitative CMR T1 and T2 mapping. Specifically, T1 and T2 maps of 26 patients with hypertrophic cardiomyopathy (HCM) were used to estimate 98 radiomic features for 7 different resampling voxel sizes (at fixed bin width), 9 different bin widths (at fixed resampling voxel size), and 7 different spatial filters (at fixed resampling voxel size/bin width). While we found a remarkable dependence of myocardial radiomic features from T1 and T2 mapping on image filters, many radiomic features showed a limited sensitivity to resampling voxel size/bin width, in terms of intraclass correlation coefficient (>0.75) and coefficient of variation ( more...

In the past few years significant changes have taken place in the diagnostic and therapeutic approach to patients with coronary artery disease (CAD) and/or ischemic heart disease (IHD). New discoveries about the development and progression of coronary atherosclerosis have changed the clinical landscape. At the same time a marked decrease in cardiovascular (CV) mortality and CAD incidence have been observed in many Countries but particularly in the most industrialized ones. This fall has been also observed in the incidence of stroke, sudden death, myocardial ischemia, myocardial infarction (MI), and prevalence of CAD. As a consequence, an increasing number of patients with chest pain exhibits non-significant stenosis at both invasive and non-invasive coronary angiography and the rate of coronary vessels revascularizations has greatly reduced. Coronary atherosclerosis and its characteristics have shown to be both diagnostic and therapeutic targets beyond obstructive CAD. The decreased prevalence of CAD in the general population has modified the pre-test probability (PTP) of disease. In this landscape the conventional stress imaging tests appear to have limited accuracy making the diagnosis of obstructive CAD very challenging. These diagnostic tests have been introduced and tested in a population with a much higher probability of disease and therefore the contemporary accuracy of these old tests appear much lower than in the past. In addition, in the past few years the relevance of the traditional ischemia guided coronary intervention strategy has been questioned. Given the low CV events granted by an optimal medical therapy in CAD the major attention has been directed on detecting coronary atherosclerosis. The earlier the better. At the same time, a growing number of data from clinical studies have shown a significant prognostic role for non-obstructive CAD and coronary atherosclerosis. All these facts have shifted the clinicians' attention from the functional evaluation of the coronary circulation to the anatomic burden of disease. more...

BACKGROUND AND PURPOSE Fractal dimension (FD) is an index of structural complexity of cortical gray matter (GM) and white matter (WM). Application of FD to pontocerebellar degeneration has revealed cerebellar changes. However, so far, possible concurrent cerebral changes and progression of changes in brain complexity have not been investigated. METHODS We computed FD of cerebellar and cerebral cortex and WM derived from longitudinal brain MRI of patients with spinocerebellar ataxia type 2 (SCA2), which is an inherited cause of pontocerebellar degeneration. Nine SCA2 patients and 16 age-matched healthy controls were examined twice (3.6 ± .7 and 3.3 ± 1.0 years apart, respectively) on the same 1.5T MR scanner with T1-weighted imaging. Cortical GM and WM of the cerebrum and cerebellum were segmented using FreeSurfer and FD of these segmentations were computed. RESULTS At baseline, FD values of cerebellar GM and WM were significantly (P < .001) lower in SCA2 patients (2.48 ± .04 for GM and 1.74 ± .09 for WM) than in controls (2.56 ± .02 for GM and 2.22 ± .19 for WM). Also, FD values of cerebral GM were significantly (P < .05) lower in SCA2 patients (2.39 ± .03) than in controls (2.43 ± .02). No significant differences were observed for FD of the cerebral WM. The rate of change of FD values was not significantly different between SCA2 patients and controls. CONCLUSIONS The structural complexity of the cerebellum and cerebral cortex is reduced in SCA2 patients. Fractal analysis seems not to be able to demonstrate progression of changes associated with degeneration in SCA2. more...

BACKGROUND AND PURPOSE Diffusion tensor imaging (DTI) is sensitive to brain microstructural changes. The aims of this DTI study were to map voxelwise the spatial distribution of brain microstructural changes in patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and to investigate any correlation between DTI-derived indices and extension of T2 hyperintensity. METHODS Eighteen patients with CADASIL and 18 age-, sex-, and education-level-matched healthy controls underwent magnetic resonance imaging at 3 T. Differences in DTI-derived indices (mean diffusivity [MD], fractional anisotropy [FA], axial [AD] and radial [RD] diffusivities, and mode of anisotropy [MO]) of brain white matter (WM) between CADASIL patients and healthy subjects were assessed through tract-based spatial statistics. Then, DTI-derived indices were correlated with the patient's score on the extended Fazekas visual scale of the T2 hyperintensity. RESULTS When compared to healthy controls, CADASIL patients showed extensive symmetric areas of increased MD/RD and decreased AD/FA/MO that involved almost the entire hemispheric cerebral WM (internal and external capsule, WM of the temporal poles, superior and inferior longitudinal fasciculus, inferior frontal-occipital fasciculus, uncinate fasciculus, cingulum, forceps major and minor, corticospinal tracts, and thalamic radiations), thalami, and corpus callosum. Additional areas of increased RD were observed in pons, midbrain, cerebellar peduncles, and cerebellar WM. Only FA was negatively correlated with extended Fazekas visual score. CONCLUSIONS Our results indicate that brain damage in CADASIL is associated with extensive microstructural changes implying impairment of intra- and inter-hemispheric cerebral, thalamocortical, and cerebrocerebellar connections. Severity of microstructural changes correlates with extension of T2 hyperintensity. more...

Background: Transthoracic echocardiography (TTE) may detect the origin and/or abnormal course of coronary epicardial vessels. We describe a novel TTE pattern specific for the anomalous origin of a left coronary vessel from the right coronary sinus and a posterior course and its prevalence in an unselected population of ambulatory patients. Methods: We prospectively studied 3692 consecutive patients who performed a routine TTE. In these subjects we looked for an abnormal finding that we found associated with the anomalous aortic origin of a coronary artery. Computed Tomography of the Coronary Arteries (CTCA) was performed in each suspected case. Results: We found a TTE aspect suggestive for a coronary anomaly and a retroaortic course in 16 subjects out of the 3298 studied (0,48%). CTCA invariably confirmed the presence of the anomaly. In 15 out of the 16 patients the left coronary vessel originating from the right coronary sinus (RCS) was the left circumflex artery (LCX). In the remaining patient the anomalous vessel was the left main coronary artery . Conclusions: We found a TTE sign specific for a particular kind of coronary anomaly. By using TTE it is possible to detect the retroaortic course of an anomalous left coronary vessel originating from the RCS. This pattern was found to be rare but pathognomonic for this specific kind of congenital anomaly. The ability to detect this specific kind of coronary anomaly by TEE may be relevant to the patient in some cases thus representing useful clinical information. more...

Aims: To test T1 and T2 mapping in the assessment of acute myocardial injury in patients with non-ST-segment elevation myocardial infarction (NSTEMI), evaluated before revascularization. Methods: Forty-seven patients with acute NSTEMI underwent cardiac magnetic resonance (CMR) at 1.5 T, including T1 and T2 mapping. Results: Coronary angiography (CA) evidenced an obstructive coronary artery disease (CAD) in 36 patients (80%) and a non-obstructive CAD in 11 patients (20%). Edema was detected in 51.1/65.9% of patients in T1/T2 maps, respectively. This difference was due to artifacts in T1 maps. T1/T2 values were significantly higher in the infarcted myocardium (IM) compared with the remote myocardium (RM) (in T1: 1151.6 ± 53.5 ms vs. 958.2 ± 38.6 ms, respectively; in T2: 69 ± 6 ms vs. 51.9 ± 2.9 ms, respectively; p < 0.0001 for both). We found both an obstructive CAD at CA and myocardial edema at CMR in 53.2% of patients, while 8.5% of patients had a non-obstructive CAD and no edema. However, 25.5% of patients had an obstructive CAD without edema, while 12.8% of patients showed edema despite a non-obstructive CAD. Furthermore, in 6 of the edema-positive patients with multi-vessels obstructive CAD, CMR identified myocardial edema in a vascular territory different from that of the lesion supposed to be the culprit at CA. Conclusions: In a non-negligible percentage of NSTEMI patients, T1 and T2 mapping detect myocardial edema without significant stenosis at CA and vice versa. Therefore, CA and CMR edema imaging might provide complementary information in the evaluation of NSTEMI. more...

In this study, we employ a time-varying, probabilistic model of linear and nonlinear heartbeat dynamics to investigate the possibility of detecting subtle autonomic alterations in subjects suffering from amnestic mild cognitive impairment (aMCI) by exploiting heartbeat information alone. aMCI is a frequent form of cognitive dysfunction which increases the risk of culminating in Alzheimer's disease (AD)-related dementia, and previous studies have demonstrated that AD is accompanied by alterations in autonomic function, which in turn have been linked to cognitive performance in non-demented subjects. We compare 13 MCI patients without ouvert dysautonomia to 13 age- and gender-matched healthy controls by feeding an autonomic nervous system-related linear and nonlinear feature set into a classification framework. Our results show a satisfactory classification performance (73% balanced accuracy), which dropped to 65% when excluding cardiovascular nonlinear/complex features. This outcome confirms the presence of subtle autonomic dysfunction in aMCI (a possible prodromal condition to AD), which can only be detected through to the use of our comprehensive modeling strategy which comprises time-varying, nonlinear/complex estimates of heartbeat dynamics. more...

Brugada syndrome (BrS) has been originally considered to occur in structural normal hearts. However recent pathological and imaging data suggest that structural and functional changes may be present in this syndrome. This study was designed to elucidate whether any macroscopic heart abnormality is detectable in patients with BrS. For this purpose we used cardiac magnetic resonance (CMR). Twenty-nine patients displaying the BrS type-1 ECG pattern and 29 healthy controls underwent CMR (1.5 Tesla). Left (LV) and right ventricular (RV) dimensions, function and regional contractility were evaluated. Late-gadolinium-enhancement (LGE) imaging was obtained in 24 patients. We found no difference between BrS patients and controls regarding LV and RV dimensions and ejection fraction. RV wall motion abnormalities (WMA) were detected in 19 patients (65.5%) and in 22 control subjects (75.9%). The majority of these WMA were attributable to areas of hypokinesia and found in the RV inferior wall. None of the patients showed LGE. No differences were detected between controls and the different subgroups of BrS patients according to symptoms, family history and spontaneous type-1 ECG pattern. BrS patients do not differ from normal subjects with regard to dimensions and global function of both LV and RV. BrS patients may show RV-WMA, however similar changes are also present in healthy subjects and may therefore represent a physiological behaviour of RV. The lack of LGE further confirms the absence of myocardial structural damage. Our results indicate that BrS seems to occur in individuals with structurally and functionally normal heart. more...

Voxel-based morphometry (VBM) enables an unbiased in-vivo whole-brain quantitative analysis of differences in gray matter (GM), white matter (WM) and cerebro-spinal fluid (CSF) volumes. We assessed with VBM 20 spinocerebellar ataxia Type 2 (SCA2) patients with mild or moderate cerebellar deficit and 20 age and sex-matched healthy controls. SCA2 patients showed a significant (P 0.01) correlation was observed between the GM and WM loss and severity of the neurological deficit. In SCA2 patients with mild to moderate cerebellar deficit, GM and WM volume loss and CSF volume increase are confined to the posterior cranial fossa. more...

BACKGROUND AND PURPOSE: Widespread cerebral changes are observed in advanced stages of Parkinson disease (PD), suggesting that PD is a multisystem disorder. We investigated with MR imaging whether global brain changes are present in early clinical stages of PD and correlated the findings with the type of clinical presentation. MATERIALS AND METHODS: T1-weighted images and mean diffusivity and fractional anisotropy (FA) maps calculated from diffusion tensor imaging (DTI) were obtained in 27 patients with de novo drug-naive PD, who were classified according to the clinical features in tremor-dominant type ( n = 13), akinetic-rigid type ( n = 11), and mixed type ( n = 3). Sixteen healthy subjects provided control data. With SIENAX software, total brain, gray matter (GM), and white matter (WM) volumes were computed from T1-weighted images, whereas brain histograms were obtained from mean diffusivity and FA maps. RESULTS: Total brain, GM and WM volumes were not significantly different in patients as a whole or subgroups and controls. As compared with controls, patients with PD as a whole and patients with the akinetic-rigid type showed an increase ( P ≤ .01) of the twenty-fifth percentile of the FA histogram. In patients with the akinetic-rigid type, there also was a trend toward an increase of the mean and fiftieth and seventy-fifth percentiles, and a reduction of the skewness of the FA histogram. Patients with tremor-dominant type showed a trend toward an increase of the twenty-fifth percentile of the FA histogram. CONCLUSIONS: In patients with de novo PD, there is an increase of FA values, more pronounced in patients with the akinetic-rigid type, probably reflecting diffuse subtle GM loss. This is in line with the hypothesis that widespread neurodegeneration is already present at the time of the clinical onset. more...

Spinocerebellar ataxia type 2 (SCA2) is the second most frequent autosomal dominant inherited ataxia worldwide. We investigated the capability of magnetic resonance imaging (MRI) to track in vivo progression of brain atrophy in SCA2 by examining twice 10 SCA2 patients (mean interval 3.6 years) and 16 age- and gender-matched healthy controls (mean interval 3.3 years) on the same 1.5 T MRI scanner. We used T1-weighted images and tensor-based morphometry (TBM) to investigate volume changes and the Inherited Ataxia Clinical Rating Scale to assess the clinical deficit. With respect to controls, SCA2 patients showed significant higher atrophy rates in the midbrain, including substantia nigra, basis pontis, middle cerebellar peduncles and posterior medulla corresponding to the gracilis and cuneatus tracts and nuclei, cerebellar white matter (WM) and cortical gray matter (GM) in the inferior portions of the cerebellar hemisphers. No differences in WM or GM volume loss were observed in the supratentorial compartment. TBM findings did not correlate with modifications of the neurological deficit. In conclusion, MRI volumetry using TBM is capable of demonstrating the progression of pontocerebellar atrophy in SCA2, supporting a possible role of MRI as biomarker in future trials. more...

The presence of brain atrophy and its progression in early Parkinson's disease (PD) are still a matter of debate, particularly in patients without cognitive impairment. The aim of this longitudinal study was to assess whether PD patients who remain cognitively intact develop progressive atrophic changes in the early stages of the disease. For this purpose, we employed high‐resolution T1‐weighted MR imaging to compare 22 drug‐naïve de novo PD patients without cognitive impairment to 17 age‐matched control subjects, both at baseline and at three‐year follow‐up. We used tensor‐based morphometry to explore the presence of atrophic changes at baseline and to compute yearly atrophy rates, after which we performed voxel‐wise group comparisons using threshold‐free cluster enhancement. At baseline, we did not observe significant differences in regional atrophy in PD patients with respect to control subjects. In contrast, PD patients showed significantly higher yearly atrophy rates in the prefrontal cortex, anterior cingulum, caudate nucleus, and thalamus when compared to control subjects. Our results indicate that even cognitively preserved PD patients show progressive cortical and subcortical atrophic changes in regions related to cognitive functions and that these changes are already detectable in the early stages of the disease. Hum Brain Mapp 35:3932–3944, 2014. © 2014 Wiley Periodicals, Inc. more...

Parkinson's disease (PD) has been reported to involve postganglionic sympathetic failure and a wide spectrum of autonomic dysfunctions including cardiovascular, sexual, bladder, gastrointestinal and sudo-motor abnormalities. While these symptoms may have a significant impact on daily activities, as well as quality of life, the evaluation of autonomic nervous system (ANS) dysfunctions relies on a large and expensive battery of autonomic tests only accessible in highly specialized laboratories. In this paper we aim to devise a comprehensive computational assessment of disease-related heartbeat dynamics based on instantaneous, time-varying estimates of spontaneous (resting state) cardiovascular oscillations in PD. To this end, we combine standard ANS-related heart rate variability (HRV) metrics with measures of instantaneous complexity (dominant Lyapunov exponent and entropy) and higher-order statistics (bispectra). Such measures are computed over 600-s recordings acquired at rest in 29 healthy subjects and 30 PD patients. The only significant group-wise differences were found in the variability of the dominant Lyapunov exponent. Also, the best PD vs. healthy controls classification performance (balanced accuracy: 73.47%) was achieved only when retaining the time-varying, non-stationary structure of the dynamical features, whereas classification performance dropped significantly (balanced accuracy: 61.91%) when excluding variability-related features. Additionally, both linear and nonlinear model features correlated with both clinical and neuropsychological assessments of the considered patient population. Our results demonstrate the added value and potential of instantaneous measures of heartbeat dynamics and its variability in characterizing PD-related disabilities in motor and cognitive domains. more...

BACKGROUND AND PURPOSE Imaging biomarkers of disease progression are desirable in inherited ataxias. MRI has demonstrated brain damage in Friedreich ataxia (FRDA) in form of regional atrophy of the medulla, peridentate cerebellar white matter (WM) and superior cerebellar peduncles (visible in T1-weighted images) and of change of microstructural characteristics of WM tracts of the brainstem, cerebellar peduncles, cerebellum, and supratentorial structures (visible through diffusion-weighted imaging). We explored the potential of brain MR morphometry and diffusion tensor imaging (DTI) to track the progression of neurodegeneration in FRDA. METHODS Eight patients (5F, 3M; age 13.4-41.2 years) and 8 healthy controls (2F, 6M; age 26.2-48.3 years) underwent 2 MRI examinations (mean 3.9 and 4.1 years apart, respectively) on the same 1.5T scanner. The protocol included 3D T1-weighted images and axial diffusion-weighted images (b-value 1,000 s/mm2) for calculating maps of fractional anisotropy, mean, axial and radial diffusivity, and mode of anisotropy. Tensor-based morphometry was used to investigate regional volume changes and tract-based spatial statistics was used to investigate microstructural changes in WM tracts. RESULTS Longitudinal analyses showed no differences in regional volume changes but a significant difference in axial diffusivity changes in cerebral and corpus callosum WM of patients as compared to controls (mean longitudinal rate of change for axial diffusivity: −.02 × 10-3 mm2/s/year in patients vs. .01 × 10-3 mm2/s/year in controls). No correlation with number of triplets, disease duration, and worsening of the clinical deficit was observed. CONCLUSION DTI can track brain microstructural changes in FRDA and can be considered a potential biomarker of disease progression. more...

Neurosarcoidosis occurs in 5-15% of sarcoidosis cases. Approximately 50% of patients with neurosarcoidosis present with a neurological disease at the time sarcoidosis is first diagnosed. Spinal sarcoidosis is rare. We report the case of a 61-year-old man with a highly aspecific intramedullary lesion as the first manifestation of sarcoidosis. One year after the onset of neurological symptoms, the high levels of angiotensin-converting enzyme and the results of a total body gallium scan and bronchoalveolar lavage supported the diagnosis of sarcoidosis. Isolated single reports indicate that spinal neurosarcoidosis may be the initial manifestation of sarcoidosis. In our case, magnetic resonance imaging of the dorsal spine showed a largely aspecific lesion. Neurosarcoidosis should be considered in the differential diagnosis of intramedullary cord lesion with leptomeningeal enhancement; a systematic search for evidence of sarcoidosis should be mandatory in all cases for a correct diagnosis and early treatment. more...

BACKGROUND AND PURPOSE: The ability of DTI to track the progression of microstructural damage in patients with inherited ataxias has not been explored so far. We performed a longitudinal DTI study in patients with spinocerebellar ataxia type 2. MATERIALS AND METHODS: Ten patients with spinocerebellar ataxia type 2 and 16 healthy age-matched controls were examined twice with DTI (mean time between scans, 3.6 years [patients] and 3.3 years [controls]) on the same 1.5T MR scanner. Using tract-based spatial statistics, we analyzed changes in DTI-derived indices: mean diffusivity, axial diffusivity, radial diffusivity, fractional anisotropy, and mode of anisotropy. RESULTS: At baseline, the patients with spinocerebellar ataxia type 2, as compared with controls, showed numerous WM tracts with significantly increased mean diffusivity, axial diffusivity, and radial diffusivity and decreased fractional anisotropy and mode of anisotropy in the brain stem, cerebellar peduncles, cerebellum, cerebral hemisphere WM, corpus callosum, and thalami. Longitudinal analysis revealed changes in axial diffusivity and mode of anisotropy in patients with spinocerebellar ataxia type 2 that were significantly different than those in the controls. In patients with spinocerebellar ataxia type 2, axial diffusivity was increased in WM tracts of the right cerebral hemisphere and the corpus callosum, and the mode of anisotropy was extensively decreased in hemispheric cerebral WM, corpus callosum, internal capsules, cerebral peduncles, pons and left cerebellar peduncles, and WM of the left paramedian vermis. There was no correlation between the progression of changes in DTI-derived indices and clinical deterioration. CONCLUSIONS: DTI can reveal the progression of microstructural damage of WM fibers in the brains of patients with spinocerebellar ataxia type 2, and mode of anisotropy seems particularly sensitive to such changes. These results support the potential of DTI-derived indices as biomarkers of disease progression. more...

To prospectively compare brain magnetic resonance (MR) imaging and hydrogen 1 (1H) MR spectroscopy findings and to use functional MR imaging to explore the patterns of brain activation in men and women with Fabry disease (FD).Eight men and eight women with FD (mean age, 38.8 years +/- 13.9 [standard deviation]) with absent or mild neurologic deficit and 16 healthy control subjects (eight men and eight women; mean age, 42.7 years +/- 15.3) gave informed consent to participate in the study, which was approved by the local ethical committee. Patients and control subjects underwent MR imaging, 1H MR spectroscopy of the frontal cortex and subcortical white matter, and functional MR imaging during repetitive flexion-extension of the last four fingers of the right hand. Extent of cerebral white matter damage was rated on fluid-attenuated inversion recovery MR images by using a visual score. Areas of activation were identified by using statistical parametric mapping software and the adoption of a height threshold of P.001 (uncorrected) and an extent threshold of P.05 (corrected).Men and women with FD showed a similar distribution of cerebral white matter changes, lacunar and cortical infarcts, small hemorrhages, and vertebrobasilar dolichoectasia. No significant (P.05) difference was observed between patients with FD and control subjects for concentration of N-acetylaspartate, creatine, and choline. During the motor task, patients showed recruitment of additional cortical areas in comparison with control subjects. Increased activation of the contralateral sensorimotor area correlated (P = .002) with extent of white matter damage.Subcortical ischemic changes in men and women with FD are similar and are associated with increased recruitment of the sensorimotor network during a simple motor task, which might limit the functional effect of the white matter small-vessel disease. more...

To investigate whether diffusion-weighted and magnetization transfer (MT) magnetic resonance (MR) imaging depict regional and/or global brain abnormalities in patients with Huntington disease (HD).Twenty-one carriers of the HD mutation (mean age, 58 years +/- 11 [SD]) and 21 healthy control subjects (mean age, 54 years +/- 13) underwent conventional, diffusion-weighted, and MT MR imaging. Volumes, mean apparent diffusion coefficients (ADCs), and MT ratios (MTRs) for left and right caudate nucleus, putamen, and cerebral periventricular white matter-as well as an index of normalized brain volume and whole-brain ADC and MT histograms-were computed. Asymmetry in volume, ADC, and MTR measurements in caudate nucleus, putamen, and periventricular white matter in control subjects and HD carriers were evaluated with Wilcoxon testing for paired samples. Differences in MR imaging variables between HD carriers and control subjects were evaluated with Mann-Whitney U testing; correlations between stages of clinical severity and MR imaging data were investigated with Spearman rank correlation testing.No significant asymmetry was observed for any of the MR imaging variables. Caudate nucleus, putamen, and whole-brain volumes were smaller (P.001 for all) in HD carriers than in control subjects. HD carriers also had increased ADC in the caudate nucleus (P =.002), putamen (P. 001), cerebral periventricular white matter (P.001), and whole brain (P.001). MTR was not significantly different between HD carriers and control subjects. Correlation was observed between stages of increasing clinical disease severity and both decrease in volume of caudate nucleus (Spearman rho = -0.63), putamen (rho = -0.64), and whole brain (rho = -0.46) and increase in ADC in caudate nucleus (rho = 0.52), periventricular white matter (rho = 0.45), and whole brain (rho = 0.44).Regional and global volume loss in HD is accompanied by an increase in ADC; this correlates with disease severity. more...

Magnetic resonance (MR) techniques enable in vivo measurement of the atrophy of the brainstem and cerebellum in spinocerebellar ataxia type 1 (SCA1) and 2 (SCA2) patients, which is accompanied by a decrease in the concentration of N-acetyl aspartate (NAA) or of the NAA/creatine ratio in the pons and cerebellum. Mean diffusivity (D) is emerging as an additional sensitive and quantitative MR parameter to investigate brain diseases. In order to explore differences between the MR features of SCA1 and SCA2 and correlate the MR and clinical findings in the two conditions, we examined 16 SCA1 patients, 12 SCA2 patients and 20 healthy control subjects. The MR protocol included T1-weighted 3D gradient echo sequences, single-voxel proton spectroscopy of the right cerebellar hemisphere (dentate and peridentate region) and of the pons with a PRESS sequence and an external reference quantitation method, and (in nine patients with SCA1 and nine patients with SCA2) diffusion-weighted echo-planar images with reconstruction of the D maps. The patients were evaluated with the Inherited Ataxia Clinical Rating Scale (IACRS). Compared with control subjects, the SCA1 and SCA2 patients showed a decrease (P < 0.01) in the volume of the brainstem and cerebellum and in the concentration of NAA in the pons and cerebellar hemisphere, whereas D of the brainstem and cerebellum was increased. No significant difference was observed between the SCA1 and SCA2 patient groups. No correlation between cerebellar volume and dentate and peridentate NAA concentration was found in SCA1 or SCA2 patients. The volume of the brainstem, D of the brainstem and cerebellum and the concentration of NAA in the pons were correlated (P < 0.05) with the IACRS score in SCA1 but not in SCA2. This discrepancy is in line with the clinical observation that the clinical deficit has a later onset and faster progression in SCA1 and an earlier onset and slower progression in SCA2, and suggests that neurodegeneration of the brainstem is a comparatively more rapid process in SCA1. In conclusion, our study indicates that SCA1 and SCA2 substantially exhibit the same MR features. The correlation in SCA1 between clinical severity and quantitative volumetric, diffusion MRI and proton MR spectroscopy findings in the brainstem indicates that these measurements might be employed for longitudinal studies and hopefully as surrogate markers in future pharmacological trials of this condition. more...

Analysis of the apparent diffusion coefficient (ADC) maps derived from diffusion-weighted MR imaging is emerging as a reproducible, sensitive, and quantitative tool to evaluate brain damage in diseases of the white and gray matter. To explore the potentials of ADC maps analysis in degenerative ataxias, we examined 28 patients and 26 age-matched controls with T1, T2, and diffusion (b values 0-1000 along the three main body axes)-weighted MR images. Twenty-four patients had inherited genetically proven diseases including spinocerebellar ataxia type 1 (SCA1) (n = 9), spinocerebellar ataxia type 2 (SCA2) (n = 8), and Friedreich's ataxia (FA) (n = 7), whereas four patients had sporadic adult onset pure cerebellar ataxia (three idiopathic, one gluten intolerance). Area and linear measurements of the CNS structures contained in the posterior cranial fossa (PCF) preliminary enabled classification of the patients in the three morphological categories reflecting the gross pathology findings, namely olivopontocerebellar atrophy (OPCA) (n = 10: six SCA2 and four SCA1), spinal atrophy (SA) (n = 7: all FA), and cortical cerebellar atrophy (CCA) (n = 4: three idiopathic and one gluten intolerance). Seven patients with SCA1 (n = 5) or SCA2 (n = 2) had morphologic changes reminiscent of OPCA, but their values were still in the lower normal range and were classified as undefined. Mean diffusivity (D) maps of the entire brain were generated and D was measured with regions of interest (ROI) in the medulla, pons, middle cerebellar peduncles, and the peridentate white matter. Moreover, after exclusion of the skull with manual segmentation and of the CSF with application of a threshold value, histograms were obtained for D of the brainstem and cerebellum and for D of the cerebral hemispheres. As compared to controls, a (P0.001) increase of D was observed in the medulla, middle cerebellar peduncles, and peridentate white matter in OPCA and undefined patients groups who had also significantly increased values of the 25th and 50th percentiles in the brainstem and cerebellum D histogram. In CCA (P = 0.01), an increase of the 25th and 50th percentile of the D value was observed in the brainstem and cerebellum histograms. The SA group showed (P0.001) an increased D in the medulla only. A correlation between clinical severity as assessed with the Inherited Ataxias Clinical Rating Scale (IACRS) and the 50th percentile of the D value in the brainstem and cerebellum histogram (r = 0.69) was observed in patients with SCA1 or SCA2. Diffusion MR imaging reveals variable patterns of increase of D in the brainstem, cerebellum, and cerebral hemispheres in degenerative ataxias that match the known distribution of the neuropathological changes. more...

BACKGROUND AND PURPOSE: Parkinson's disease (PD) is a progressive neurodegenerative disorder with motor and non-motor symptoms, including cognitive deficits. Several magnetic resonance imaging approaches have been applied to investigate brain atrophy in PD. The aim of this study was to detect early structural cortical and subcortical changes in de novo PD whilst distinguishing cognitive status, clinical phenotype and motor laterality. METHODS: Eighteen de novo PD with mild cognitive impairment (PD-MCI), 18 de novo PD without MCI (PD-NC) and 18 healthy control subjects were evaluated. In the PD-MCI group, nine were tremor dominant and nine were postural instability gait disorder (PIGD) phenotype; 11 had right-sided symptom dominance and seven had left-sided symptom dominance. FreeSurfer was used to measure cortical thickness/folding, subcortical structures and to study group differences as well as the association with clinical and neuropsychological data. RESULTS: Parkinson's disease with MCI showed regional thinning in the right frontal, right middle temporal areas and left insula compared to PD-NC. A reduction of the volume of the left and right thalamus and left hippocampus was found in PD-MCI compared to PD-NC. PD-MCI PIGD showed regional thinning in the right inferior parietal area compared to healthy controls. A decreased volume of the left thalamus was reported in PD-MCI with right-sided symptom dominance compared to PD-NC and PD-MCI with left-sided symptom dominance. CONCLUSIONS: When MCI was present, PD patients showed a fronto-temporo-parietal pattern of cortical thinning. This cortical pattern does not appear to be influenced by motor laterality, although one-sided symptom dominance may contribute to volumetric reduction of specific subcortical structures. more...

The ability to image the whole brain through ever more subtle and specific methods/contrasts has come to play a key role in understanding the basis of brain abnormalities in several diseases. In magnetic resonance imaging (MRI), “diffusion” (i.e. the random, thermally-induced displacements of water molecules over time) represents an extraordinarily sensitive contrast mechanism, and the exquisite structural detail it affords has proven useful in a vast number of clinical as well as research applications. Since diffusion-MRI is a truly quantitative imaging technique, the indices it provides can serve as potential imaging biomarkers which could allow early detection of pathological alterations as well as tracking and possibly predicting subtle changes in follow-up examinations and clinical trials. Accordingly, diffusion-MRI has proven useful in obtaining information to better understand the microstructural changes and neurophysiological mechanisms underlying various neurodegenerative disorders. In this review article, we summarize and explore the main applications, findings, perspectives as well as challenges and future research of diffusion-MRI in various neurodegenerative disorders including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease and degenerative ataxias. more...

BACKGROUND AND PURPOSE: Manually drawn VOI-based analysis shows a decrease in magnetization transfer ratio in the hippocampus of patients with Alzheimer disease. We investigated with whole-brain voxelwise analysis the regional changes of the magnetization transfer ratio in patients with mild Alzheimer disease and patients with amnestic mild cognitive impairment. MATERIALS AND METHODS: Twenty patients with mild Alzheimer disease, 27 patients with amnestic mild cognitive impairment, and 30 healthy elderly control subjects were examined with high-resolution T1WI and 3-mm-thick magnetization transfer images. Whole-brain voxelwise analysis of magnetization transfer ratio maps was performed by use of Statistical Parametric Mapping 8 software and was supplemented by the analysis of the magnetization transfer ratio in FreeSurfer parcellation-derived VOIs. RESULTS: Voxelwise analysis showed 2 clusters of significantly decreased magnetization transfer ratio in the left hippocampus and amygdala and in the left posterior mesial temporal cortex (fusiform gyrus) of patients with Alzheimer disease as compared with control subjects but no difference between patients with amnestic mild cognitive impairment and either patients with Alzheimer disease or control subjects. VOI analysis showed that the magnetization transfer ratio in the hippocampus and amygdala was significantly lower (bilaterally) in patients with Alzheimer disease when compared with control subjects (ANOVA with Bonferroni correction, at P < .05). Mean magnetization transfer ratio values in the hippocampus and amygdala in patients with amnestic mild cognitive impairment were between those of healthy control subjects and those of patients with mild Alzheimer disease. Support vector machine-based classification demonstrated improved classification performance after inclusion of magnetization transfer ratio-related features, especially between patients with Alzheimer disease versus healthy subjects. CONCLUSIONS: Bilateral but asymmetric decrease of magnetization transfer ratio reflecting microstructural changes of the residual GM is present not only in the hippocampus but also in the amygdala in patients with mild Alzheimer disease. more...

Paroxysmal dyskinesias (PxDs) are involuntary, episodic moveents including any combination of dystonia, ballism, chorea, r athetosis [1]. The events may be precipitated by sudden volntary movements (paroxysmal kinesigenic dyskinesias) or may ccur spontaneously at rest (paroxysmal non-kinesigenic dyskineias precipitated by caffeine, alcohol, fatigue and emotional stress). n uncommon type of PxD is precipitated by exertion and is called aroxysmal exertion-induced dyskinesia (PED) [1]. Although most ases of PxD are primary, specific cause could be recognized such as ultiple sclerosis, vascular lesions, trauma, or acquired metabolic bnormalities [1]. more...

BACKGROUND AND PURPOSE: Previous fMRI studies indicated a relationship between changes of the cortical activation pattern and disease severity in Parkinson's disease (PD). Early diagnosis of Parkinson's disease offers the opportunity to evaluate the putative neuroprotective and disease-modifying effects of drugs at a clinical stage when they might be more effective. The aim of this study was to assess motor cortex reorganization at the earliest clinically detectable stage of PD and the effects on it of chronic dopaminergic treatment. METHODS: We evaluated with fMRI 11 de novo patients with right unilateral parkinsonism during execution of a controlled hand-tapping task by the unaffected left hand. In 7 of them fMRI examination with the same task was repeated after 6 months of ropinirole administration. RESULTS: At baseline, as compared to control subjects, PD patients showed significant hypoactivation of right sensory-motor cortex (SM1) and hyperactivation of the left parietal superior and inferior gyri and frontal superior gyrus and of the right parietal superior gyrus and precuneus. Ropinirole treatment yielded a significant clinical improvement (mean UPDRS score subitem III 13.4 at baseline, 9.4 at follow-up; p < 0.001 at a paired t-test) which was combined with lower activation in the left parietal superior and inferior gyri and in right parietal and occipital superior gyri with respect to their baseline fMRI examination. CONCLUSIONS: Our results indicate that in PD patients changes in cortical activation precede the onset of motor symptoms in the clinically unaffected side and are partially reversed by chronic administration of long acting dopamine agonist ropinirole. more...

INTRODUCTION: Nuclear medicine studies in Parkinson's disease (PD) indicate that nigrostriatal damage causes a widespread cortical hypoactivity assumed to be due to reduced excitatory thalamic outflow. However, so far, functional MRI (fMRI) studies have provided controversial data about this "functional deafferentation" phenomenon. To further clarify this issue, we assessed, with fMRI, de novo drug-naive PD patients using a relatively complex motor task under strictly controlled conditions. METHODS: Nineteen de novo PD patients with right-predominant or bilateral symptoms and 13 age-matched healthy volunteers performed continuous writing of "8" figures with the right-dominant hand using a MR-compatible device that enables identification of incorrectly performed tasks and measures the size and the frequency of the "8"s. The data were analyzed with FSL software and correlated with the clinical severity rated according to the Hoehn and Yahr (HY) staging system. RESULTS: Fifteen (89%) of 19 PD patients and 12 (92%) of 13 controls correctly executed the task. PD patients showed significant hypoactivation of the left primary sensorimotor cortex (SM1) and cerebellum and no hyperactive areas as compared to controls. However, activation in SM1 and supplementary motor area bilaterally, in left supramarginal, parietal inferior, parietal superior and frontal superior gyri as well as in right parietal superior and angular gyri paralleled increasing disease severity as assessed with the HY stage. CONCLUSIONS: In line with the "deafferentation hypothesis", fMRI demonstrates hypoactivation of the SM1 in the early clinical stage of PD. more...

A child presented with recurrent episodes of lethargia for which he underwent several hospital admissions and investigations. A further episode culminated in respiratory arrest and hypoxic ischemic encephalopathy with permanent mental regression. Eighteen months later the mother was discovered while providing clonidine pills to the child; the mother appears to feature a Munchausen syndrome by proxy. more...

BACKGROUND AND PURPOSE: GM is typically affected in HD since the presymptomatic stage. Our aim was to investigate with MT MR imaging the microstructural changes of the residual brain subcortical and cortical GM in carriers of the HD gene and to preliminarily assess their correlation with the clinical features. MATERIALS AND METHODS: Fifteen HD gene carriers with a range of clinical severity and 15 age- and sex-matched healthy controls underwent MT MR imaging on a 1.5T scanner. The MT ratio was measured automatically in several subcortical and cortical GM regions (striatal nuclei; thalami; and the neocortex of the frontal, temporal, parietal, and occipital lobes) by using FLS tools. RESULTS: The MT ratio was significantly (P < .05 with Bonferroni correction for multiple comparison) decreased in all subcortical structures except the putamen and decreased diffusely in the cerebral cortex of HD carriers compared with controls. Close correlation was observed between the subcortical and cortical regional MT ratios and several clinical variables, including disease duration, motor disability, and scores in timed neuropsychological tests. CONCLUSIONS: MT imaging demonstrates degeneration of the subcortical and cortical GM in HD carriers and might serve, along with volumetric assessment, as a surrogate marker in future clinical trials of HD. more...

Previous fMRI studies using motor tasks yielded conflicting results concerning the activation pattern in Parkinson's disease (PD) patients. Possible explanations of these discrepancies include differences in the clinical features of the examined patients and in the executed tasks and incomplete task monitoring. We evaluated with fMRI 20 patients with untreated de-novo PD and 11 healthy controls with a simple motor task consisting of self-paced continuous right hand-tapping. The task was monitored on-line with a dedicated device which measures the strength and frequency of the tapping. Fifteen patients performed the task correctly. The frequency was not significantly different, whereas force was slightly different between patients (26.4 ± 3.0 N) and controls (28.5 ± 2.4 N) (p = 0.046, Mann–Whitney U-test). After insertion of the subject's frequency and force as covariate variables in the model, PD patients compared to controls showed areas of significantly [Z statistic image > 5.1 and p ≤ 0.05 (corrected) cluster significance] lower activation in the left primary sensorimotor (SM1) cortex and cerebellum and higher activation in the left temporal–parietal cortex adjacent to the SM1 and in right SM1. Furthermore in PD patients the disease severity evaluated with the Hoehn and Yahr staging system correlated significantly [Z statistic image > 2.3 and p ≤ 0.05 (corrected) cluster significance] with activation of left SM1 and supplementary motor area and cingulum, bilaterally. The mixed pattern of decreased and increased cortical activation in de novo PD patients possibly reflects the coexistence of cortical deafferentation, and compensatory phenomena by cortico-cortical circuits. more...

A 76-year-old woman was admitted to the Cardiology ward because of chest pain. She had a history of poor controlled arterial hypertension. Two-dimensional echocardiography showed a dilated ascending aorta without signs of intimal tears. The aortic valve showed normal function. There were no sign of pericardial effusion, and wall motion of the left ventricle was normal. Laboratory tests did not show abnormalities. To evaluate the coronary arterial tree and the ascending aorta, a 64-multislice computed tomography (MSCT) … more...

Presenilin 1 (PS1) mutation carriers provide the opportunity to asses early features of neurodegeneration in familial Alzheimer’s disease (AD). Gray matter (GM) regional volume loss and decrease of magnetization transfer ratio (MTR) consistent with microstructural changes have been reported in sporadic AD. We performed a regional volumetric and MTR analysis in carriers of PS1 mutations. Six non-demented mutated PS1 carriers (5 with memory deficits) and 14 healthy subjects were examined with high resolution T1-weighted images for volumetry and with T2* weighted images for MTR. Cortical GM volume and MTR values were derived. Compared to healthy controls, the GM volume of the left temporal and inferior parietal cortex and the MTR of the temporal cortex bilaterally were significantly decreased in PS1 gene carriers. In the latter, the temporal lobe MTR showed a trend for correlation with memory and executive function scores. Early neurodegeneration in non-demented subjects at risk for familial AD may be associated with atrophy and decreased MTR in the temporal cortex. more...

Background and purpose Neurodegeneration in spinocerebellar ataxia type 1(SCA1) and 2(SCA2) is associated with white matter(WM) damage. Voxel-Based Morphometry(VBM), histogram analysis of mean diffusivity(MD) and Tract-Based Spatial Statistics(TBSS) enable an in vivo quantitative analysis of WM volume and structure. We assessed with these 3 techniques the whole brain WM damage in SCA1 and SCA2. Patients and methods Ten patients with SCA1, 10 patients with SCA2 and 10 controls underwent MRI with acquisition of T1-weighted and diffusion tensor images. The results were correlated with severity of clinical deficit. Results VBM showed atrophy of the brainstem and cerebellar WM without significant differences between SCA1 and SCA2. Focal atrophy of the cerebral subcortical WM was also present. Histogram analysis revealed increased MD in the brainstem and cerebellum in patients with SCA1 and SCA2 which in SCA2 was more pronounced and combined with mild increase of the MD in the cerebral hemispheres in SCA2. In SCA1 and SCA2 TBSS revealed decreased fractional anisotropy(FA) in the inferior, middle and superior cerebellar peduncles, pontine transverse fibres, medial and lateral lemnisci, spinothalamic tracts, corticospinal tracts and corpus callosum. The extent of tract changes was greater in SCA2 patients who also showed decreased FA in the short intracerebellar tracts. In both diseases VBM, histogram and TBSS results correlated with clinical severity. Conclusions Brain WM damage featuring a pontocerebeellar atrophy is similar in SCA1 and SCA2 but more pronounced in SCA2. In both diseases it correlates with severity of the clinical deficit. more...

Neuropathological description of the brain in spinocerebellar ataxia type 1(SCA1) is limited to a few cases. Voxel-based morphometry (VBM) enables an unbiased in vivo whole-brain quantitative analysis of regional differences in gray matter (GM) and white matter (WM) volume. We assessed with VBM the structural damage in patients with genetically confirmed SCA1. Fifteen SCA1 patients and 15 age-matched healthy controls underwent MR examination with acquisition of high-resolution T1-weighted images. The results were correlated with the disease duration and severity of the clinical deficit assessed with the International Cerebellar Ataxia Rating Scale (ICARS) and Inherited Ataxia Clinical Rating Scale (IACRS). As compared to controls, patients with SCA1 showed a significant (p < 0.05 corrected for multiple comparison) symmetric loss of volume of the GM in the rostral cerebellar vermis and paramedian portions of the anterior cerebellar lobes. WM was decreased in the peridentate region and middle cerebellar peduncles but not in the pons. No GM or WM volume loss was found in the cerebral hemispheres. The cerebellar and brainstem GM and WM volume loss correlated with disease duration and the ICARS and IACRS scores. VBM confirms that atrophy predominantly involves the brainstem and cerebellum in SCA1. The correlation with the clinical features indicates that VBM might be useful to monitor disease progression. more...

Autosomal dominant lateral temporal epilepsy (ADTLE) is a syndrome characterized by ictal auditory phenomena suggesting a lateral temporal lobe seizure onset and is associated with mutations in the leucine-rich, glioma inactivated 1 (LGI1) gene.1,2 The structure of the LGI1 protein includes, in the N-terminal portion, three leucine-rich repeats (LRR). The function of LGI1 and the mechanisms underlying epilepsy in patients with LGI1 mutations are not established. However, LGI1 is involved in the control of survival of neuroblastoma cell lines.3 This feature and the structural homology between LGI1 and other LRR proteins essential for the development of the CNS3 make it conceivable that LGI1 mutations could imply some structural abnormalities of the lateral temporal lobe as the substratum underlying partial epilepsy in ADTLE. Neuropathologic data are lacking and conventional MRI studies failed to show consistent findings in ADTLE.1,2 Voxel-based analyses enable detection of subtle regional differences in MR images.4,5 ### Methods. We performed voxel-based analyses of T1-weighted, diffusion-tensor, and magnetization transfer (MT) images of the brain in 8 patients (3 women and 5 men, mean age 49 ± 13 years) with ADTLE and LGI1 mutations and 24 healthy control subjects (14 women and 10 men, mean … more...

Twenty-five patients with spinal vascular malformations demonstrated by spinal arteriography (21 dural arteriovenous fistulas, 2 perimedullary arteriovenous fistulas and 2 intramedullary arteriovenous malformations) underwent MR imaging and contrast enhanced phase-contrast MR angiography before and after endovascular (n?18) or surgical (n=7) treatment. In 3 patients with dural arteriovenous fistula treated with glue embolization, early post-treatment MR angiography showed persistence of flow in the perimedullary vessels. The patency of the fistula was confirmed by spinal arteriography or surgery in all three patients. In two other patients with dural arteriovenous fistulas treated with glue injection, delayed MR angiography showed flow in perimedullary vessels which was not observable in early post-treatment MR angiography controls. Reopening (“recurrence”) of the fistula was confirmed by arteriography in one patient. In the remaining 16 patients with dural arteriovenous fistula, post-treatment MR angiography showed disappearance of flow in the perimedullary vessels consistent with obliteration of the fistula. This finding was associated with persistent intramedullary signal changes and contrast enhancement in 13 patients and perimedullary contrast enhancing vessels in 6 patients. Arteriography in one of the latter patients showed exclusion of the fistula confirming the result of the posttreatment MR angiography study. In the 4 patients with high flow spinal vascular malformations, all treated with endovascular approach, early post-treatment MR angiography showed reduction or disappearance of flow in the abnormal vessels. This remained unchanged in two patients, where as increased flow in the same vessels was demonstrated by further follow-up MR angiography studies in two patients. Phase contrast MR angiography is a useful complement to MR imaging in the post-treatment evaluation of spinal vascular malformations. An early post-treatment MR-angiography control is recommended as it enables prompt identification of treatment failures and may constitute a reference term for lesion monitoring over time. more...

FLAIR and diffusion-weighted MRI were obtained twice (mean interval 20 ± 4 months) in 10 patients with leukoaraiosis. At follow-up, visual extension of leukoaraiosis was unchanged, whereas the median of whole brain apparent diffusion coefficient (WB-ADC) histogram was increased ( p = 0.008) and brain volume index (BVI) was decreased ( p = 0.006). WB-ADC histogram and BVI are sensitive to leukoaraiosis and might be considered for monitoring progression of the disease. more...

Contrast medium was given intravenously to three nonalcoholic patients who underwent MRI or CT in the acute stage of Wernicke's encephalopathy. Pathological enhancement was not seen in one patient examined within 4 days of clinical onset, was mild in a another 3 days after clinical deterioration and marked in a patient examined 12 days after admission. Contrast enhancement of lesions was present in half of 12 cases of acute disease reported previously. There was a substantial overlap in the time interval between clinical onset and contrast-enhanced CT or MRI in the groups of enhancing and nonenhancing lesions. Since contrast enhancement may be absent in acute WE, proton-density and T 2-weighted images are more useful for diagnosis of this reversible but potentially fatal condition. more...

Objective: To describe a previously unreported clinical and radiologic presentation of hereditary transthyretin (TTR)-related amyloidosis. Background: Unexplained cerebellar ataxia, pyramidal syndrome, and hearing loss are observed in some patients with TTR-related amyloidoses. Methods: We performed clinical, radiologic, and pathologic examinations of three family members with TTR-related (Ala36Pro) amyloidosis. Results: The patient was a 69-year-old woman with vitreal amyloid deposits, progressive sensorineural deafness, cerebellar ataxia, pyramidal syndrome, and recurrent transient neurologic symptoms. Cranial MRI showed symmetric thin rims of low signal intensity in T2- and T2*-weighted images in the cortex of the sylvian fissures, of the cerebellar hemispheres and vermis, and in the quadrigeminal plate consistent with superficial siderosis of the CNS. Her older daughter had vitreal amyloid deposits, acute Brown-Sequard syndrome at C4, acute sensorineural deafness, and recurrent transient neurologic symptoms. Cranial MRI at age 48 revealed a rim of low signal intensity in T2- and T2*-weighted images in the superior vermis folia and the right sylvian cortex. In addition, two small hemosiderin deposits were seen in the left parietal cortex. Lumbar puncture yielded colorless CSF with increased ferritin content and was followed by fourth ventricle hemorrhage. Cranial MRI 11 months later showed progression of brain hemosiderin deposits. The younger daughter had vitreal deposits, sensorimotor polyneuropathy, and acute sensorineural hearing but no evidence of siderosis on cranial MRI. She died at age 43 years of posterior fossa subarachnoid hemorrhage, and the neuropathologic examination showed amyloid deposition in the leptomeningeal spaces and vessels. Conclusion: Transthyretin-related amyloidosis may cause superficial siderosis of the CNS through subarachnoid bleeding related to meningovascular amyloid deposition. more...

MR imaging enabled diagnosis of Wernicke's encephalopathy by showing symmetric areas of increased signal intensity on proton density and T2 weighted images in the periaqueductal gray matter, mammillary bodies, medial thalami and pericentral and interhemispheric cerebral cortex in three non-alcoholic patients who were examined within 3 days of admission for acute confusional state associated with ophthalmoparesis and ataxia. In two patients the initial examination was completed with intravenous contrast administration and no lesion enhancement was seen. In the third patient computed tomography 10 days after the initial MR imaging study showed marked contrast enhancement of the lesions. Our data and a review of the literature indicate that lesion contrast enhancement presumably reflecting disruption of the blood brain barrier may be lacking in the early phases of Wernicke's encephalopathy. Acquisition and careful evaluation of long TR images is crucial to the diagnosis of Wernickes encephalopathy with MR imaging in the acute phase. more...

Seven patients with solitary brain stem lesions (3 brain stem gliomas, 2 capillary telangectasias, 1 neuro-Behçet, 1 acute multiple sclerosis plaque) and 15 healthy volunteers were examined with single voxel proton MR speotroscopy using short TE STEAM or long TE PRESS techniques. The pontine spectrum in the healthy subjects showed a higher choline/creatine ratio than that observed in the normal supratentorial compartment. The three patients with brain stem glioma invariably showed a moderate to severe decrease of the N-acetyl-aspartate/creatine ratio associated with presence of lactate in two patients. The reduction of the N-acetyl aspartate/creatine ratio in the patients with non-neoplastic lesions was mild or absent and it was never associated with the presence of lactate. Even if further investigations are required to confirm these preliminary findings, our study indicates that proton MR speotroscopy may be of assistance in the differential diagnosis of neoplastic and non-neoplastic solitary brain stem lesions. more...

To investigate whether proton magnetic resonance (MR) spectroscopy is a useful complement to MR imaging in patients with degenerative ataxia.Brain MR imaging and single-voxel proton MR spectroscopy of the right cerebellar hemisphere and pons were performed in 30 patients with sporadic (n = 16) or inherited (n = 14) degenerative ataxia and in 20 healthy control subjects. Several indexes of brainstem and cerebellar atrophy were measured on MR images, as well as the N-acetylaspartate/creatine (NAA/Cr), choline/Cr (Cho/Cr), and myo-inositol/Cr (mI/Cr) ratios in the MR spectra. Differences between patients and subjects were evaluated with the Kruskal-Wallis and Mann-Whitney tests, whereas correlation of clinical, MR imaging, and spectroscopic data was assessed with nonparametric Spearman rank correlation.Measurements of brainstem and cerebellar atrophy obtained from MR images revealed patients had olivopontocerebellar atrophy (OPCA) (n = 11), spinal atrophy (SA) (n = 8), or corticocerebellar atrophy (CCA) (n = 4). Seven patients did not fulfill the criteria for any group and were considered undefined. In patients with OPCA, the pontine and cerebellar NAA/Cr and Cho/Cr ratios were significantly decreased when compared with those of the control subjects. Pontine and cerebellar NAA/Cr ratios were also significantly reduced in patients with SA and CCA. Five patients with undefined ataxia had a substantial decrease of pontine or cerebellar NAA/Cr ratio when compared with that of the control subjects. In patients with OPCA, the pontine NAA/Cr ratio (but not the atrophy measurements) showed a correlation (P =.04) with disability.MR spectroscopy is a useful complement to MR imaging in patients with degenerative ataxia. more...