Bilateral Middle Cerebellar Peduncles Research Articles

Structural connectivity at term equivalent age and language in preterm children at 2 years corrected.

We previously reported interhemispheric structural hyperconnectivity bypassing the corpus callosum in children born extremely preterm (<28 weeks) versus term children. This increased connectivity was positively associated with language performance at 4-6 years of age in our prior work. In the present study, we aim to investigate whether this extracallosal connectivity develops in extremely preterm infants at term equivalent age by leveraging a prospective cohort study of 350 very and extremely preterm infants followed longitudinally in the Cincinnati Infant Neurodevelopment Early Prediction Study. For this secondary analysis, we included only children born extremely preterm and without significant brain injury (n = 95). We use higher-order diffusion modelling to assess the degree to which extracallosal pathways are present in extremely preterm infants and predictive of later language scores at 22-26 months corrected age. We compare results obtained from two higher-order diffusion models: generalized q-sampling imaging and constrained spherical deconvolution. Advanced MRI was obtained at term equivalent age (39-44 weeks post-menstrual age). For structural connectometry analysis, we assessed the level of correlation between white matter connectivity at the whole-brain level at term equivalent age and language scores at 2 years corrected age, controlling for post-menstrual age, sex, brain abnormality score and social risk. For our constrained spherical deconvolution analyses, we performed connectivity-based fixel enhancement, using probabilistic tractography to inform statistical testing of the hypothesis that fibre metrics at term equivalent age relate to language scores at 2 years corrected age after adjusting for covariates. Ninety-five infants were extremely preterm with no significant brain injury. Of these, 53 had complete neurodevelopmental and imaging data sets that passed quality control. In the connectometry analyses adjusted for covariates and multiple comparisons (P < 0.05), the following tracks were inversely correlated with language: bilateral cerebellar white matter and middle cerebellar peduncles, bilateral corticospinal tracks, posterior commissure and the posterior inferior fronto-occipital fasciculus. No tracks from the constrained spherical deconvolution/connectivity-based fixel enhancement analyses remained significant after correction for multiple comparisons. Our findings provide critical information about the ontogeny of structural brain networks supporting language in extremely preterm children. Greater connectivity in more posterior tracks that include the cerebellum and connections to the regions of the temporal lobes at term equivalent age appears to be disadvantageous for language development.

Unusual PSMA uptake in seronegative paraneoplastic brainstem encephalitis: A case report

Paraneoplastic encephalitis, especially seronegative, is a heterogeneous group of disorders with varied symptoms at presentation. We present the case of a 63-year-old male who presented with motor weakness and altered sensorium. Magnetic resonance imaging of the brain showed altered signal intensity in the midbrain, pons, anterior part of the medulla, and bilateral middle cerebellar peduncle. T2 hyperintensity was also seen in the bilateral basal ganglia and internal capsule region. 18 fluoro-deoxyglucose positron emission tomography/computed tomography (18 FDG PET/CT) showed increased FDG uptake in the brain stem, left thalamus, and periventricular location. 68Ga-prostate-specific membrane antigen (PSMA) PET/CT done in view of elevated serum Prostate-specific antigen levels show a focal PSMA-avid lesion in the prostate gland and increased PSMA uptake in the brain stem, which is an atypical site of PSMA uptake. Our study highlights the importance of paraneoplastic syndromes with varied clinical presentation and low specificity to antibodies. These spectra of diseases are fatal but treatable and therefore should be evaluated diligently to reduce morbidity

Hot cross bun in pediatric age multi-system atrophy an unusual presentation

A 10-year-old female was brought to emergency department with complaint fever, cold, and cough for 5 days followed by weakness of upper limb weakness more than Lower limb associated with inability to walk/stand, brought to emergency with altered sensorium. Nervous system: Confused and altered, tone is normal, power: 3/3 in upper limbs 2/2 in lower limbs and reflexes in bilateral knee brisk, bilateral plantar-extensor; On general examination revealed hypomimia, dysarthria and bilateral bradykinesia along with ataxic gait and pyramidal signs. Blood investigation were normal and diagnosis made by neuroimaging s/o: Bilaterally symmetrical abnormal signal in both postero-medial thalami, bilateral insular cortices, pons and bilateral middle cerebellar peduncles. It is extending into pons involving transverse pontocerebellar tracts and median pontine raphe nuclei giving 'Hot cross bun sign' (HCBS). During course of treatment child had autonomic disturbances. Child was treated with supportive medication and methyl-presdnisolone followed by oral steroid. Child had responded to treatment given and child has been discharged with no neurological deficit on oral medications. We concluded autonomic dysfunction in any patient presenting with acute onset of weakness with short duration must evaluate for MSA and institute appropriate treatment.

Application study of DTI combined with ASL in the crossed cerebellar diaschisis after subacute cerebral hemorrhage.

To study the value of 3.0T magnetic resonance imaging with diffusion tensor imaging (DTI) and 3D-arterial spin labeling (ASL) perfusion imaging in the diagnosis of the crossed cerebellar diaschisis (CCD) after the unilateral supratentorial subacute cerebral hemorrhage. Fifty-eight patients with the unilateral supratentorial subacute cerebral hemorrhage who underwent diffusion tensor imaging (DTI), 3D-arterial spin labeling (ASL), and conventional magnetic resonance imaging (MRI) scanning were enrolled. Cerebral blood flow (CBF) values of the perihematomal edema (PHE) and bilateral cerebellar hemisphere were measured on ASL mapping, and the fractional anisotropy (FA) and mean diffusivity (MD) values of the bilateral cortical, pontine, and middle cerebellar peduncle (MCP) were measured on DTI mapping. In the CCD(+) group, FA values of the cerebral cortex and pontine ipsilateral to the lesion were statistically reduced compared to the contralateral side (P < 0.05), and the FA and MD values of the middle cerebellar peduncle (MCP) contralateral to the lesion were statistically reduced compared to the ipsilateral side (P < 0.05). Positive correlation was detected between the CBF values of the perihematomal edema (PHE) and the CBF values of cerebellar hemispheres (r = 0.642, P < 0.05), whereas the CBF values of PHE had a significantly high positive correlation with the FA in the contralateral MCP (r = 0.854, P < 0.05). CBF values in the contralateral cerebellar hemisphere correlated with FA (r = 0.466, P < 0.05) and MD values (r = 0.718, P < 0.05) in the contralateral MCP. Hemodynamic alterations of PHE and cortical-ponts-cerebellum (CPC) fibrous pathway damage are associated with the development of CCD; DTI technique can assess the degree of CPC fiber pathway injury at an early stage.

The longitudinal progression of MRI changes in pre-ataxic carriers of SCA3/MJD.

The natural history of magnetic resonance imaging (MRI) in pre-ataxic stages of spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is not well known. We report cross-sectional and longitudinal data obtained at this stage. Baseline (follow-up) observations included 32 (17) pre-ataxic carriers (SARA < 3) and 20 (12) related controls. The mutation length was used to estimate the time to onset (TimeTo) of gait ataxia. Clinical scales and MRIs were performed at baseline and after a median (IQR) of 30 (7) months. Cerebellar volumetries (ACAPULCO), deep gray-matter (T1-Multiatlas), cortical thickness (FreeSurfer), cervical spinal cord area (SCT) and white matter (DTI-Multiatlas) were assessed. Baseline differences between groups were described; variables that presented a p < 0.1 after Bonferroni correction were assessed longitudinally, using TimeTo and study time. For TimeTo strategy, corrections for age, sex and intracranial volume were done with Z-score progression. A significance level of 5% was adopted. SCT at C1 level distinguished pre-ataxic carriers from controls. DTI measures of the right inferior cerebellar peduncle (ICP), bilateral middle cerebellar peduncles (MCP) and bilateral medial lemniscus (ML), also distinguished pre-ataxic carriers from controls, and progressed over TimeTo, with effect sizes varying from 0.11 to 0.20, larger than those of the clinical scales. No MRI variable showed progression over study time. DTI parameters of the right ICP, left MCP and right ML were the best biomarkers for the pre-ataxic stage of SCA3/MJD. TimeTo is an interesting timescale, since it captured the longitudinal worsening of these structures.

Myelin Density in Normal-Appearing White Matter in Measurements by q-Space Diffusional MRI Correlates with Clinical Disability in Multiple Sclerosis (P10-3.005)

Myelin Density in Normal-Appearing White Matter in Measurements by q-Space Diffusional MRI Correlates with Clinical Disability in Multiple Sclerosis (P10-3.005)

Symptomatic care of late-onset Alexander disease presenting with area postrema-like syndrome with prednisolone; a case report

BackgroundAlexander disease (AxD) is classified into AxD type I (infantile) and AxD type II (juvenile and adult form). We aimed to determine the potential genetic cause(s) contributing to the AxD type II manifestations in a 9-year-old male who presented area postrema-like syndrome and his vomiting and weight loss improved after taking prednisolone.Case presentationA normal cognitive 9-year-old boy with persistent nausea, vomiting, and a significant weight loss at the age of 6 years was noticed. He also experienced an episode of status epilepticus with generalized atonic seizures. He showed non-febrile infrequent multifocal motor seizures at the age of 40 days which were treated with phenobarbital. He exhibited normal physical growth and neurologic developmental milestones by the age of six. Occasionally vomiting unrelated to feeding was reported. Upon examination at 9 years, a weak gag reflex, prominent drooling, exaggerated knee-deep tendon reflexes (3+), and nasal tone speech was detected. All gastroenterological, biochemical, and metabolic assessments were normal. Brain magnetic resonance imaging (MRI) revealed bifrontal confluent deep and periventricular white matter signal changes, fine symmetric frontal white matter and bilateral caudate nucleus involvements with garland changes, and a hyperintense tumefactive-like lesion in the brain stem around the floor of the fourth ventricle and area postrema with contrast uptake in post-contrast T1-W images. Latter MRI at the age of 8 years showed enlarged area postrema lesion and bilateral middle cerebellar peduncles and dentate nuclei involvements. Due to clinical and genetic heterogeneities, whole-exome sequencing was performed and the candidate variant was confirmed by Sanger sequencing. A de novo heterozygous mutation, NM_001242376.1:c.262 C > T;R88C in exon 1 of the GFAP (OMIM: 137,780) was verified. Because of persistent vomiting and weight loss of 6.0 kg, prednisolone was prescribed which brought about ceasing vomiting and led to weight gaining of 3.0 kg over the next 3 months after treatment. Occasional attempts to discontinue prednisolone had been resulting in the reappearance of vomiting.ConclusionsThis study broadens the spectrum of symptomatic treatment in leukodystrophies and also shows that R88C mutation may lead to a broad range of phenotypes in AxD type II patients.

Altered Levels of Plasma Inflammatory Cytokines and White Matter Integrity in Bipolar Disorder Patients With Suicide Attempts.

ObjectiveBipolar disorder (BD) has a higher lifetime rate of suicide attempts (SA) than other psychiatric disorders. Furthermore, BD patients with SA (BD + S) are prone to a worse quality of life. However, the pathophysiology of BD + S is poorly understood. To further reveal the potential mechanisms of BD + S, abnormalities in peripheral plasma inflammatory cytokines and brain white matter (WM) in BD + S, as well as the correlation between them are investigated.MethodsWe tested the levels of TNF-α, IL-1β, and IL-6 in peripheral plasma and collected the diffusion tensor imaging (DTI) data from 14 BD + S, 24 BD patients without SA (BD-S), and 26 healthy controls (HCs). The three groups were matched by age and gender. The levels of TNF-α, IL-1β, and IL-6 were detected by Luminex multifactor detection technology, and the fractional anisotropy (FA) values were employed to depict the alterations of WM. Partial correlation analyses were conducted to detect correlations between levels of TNF-α, IL-1β, and IL-6 and changes of WM, and the relationships between severity of clinical symptoms, including scores of HAMD-17 and YMRS, and cytokine levels or FA values in all groups.ResultsFor plasma inflammatory cytokines, there was no significant difference in their levels except for IL-6 among the three groups. Post-hoc analyses revealed that increased IL-6 level was only detected in BD + S (p < 0.05, Bonferroni correction). For DTI, BD + S showed specifically decreased FA in the bilateral middle cerebellar peduncle and the left superior corona radiata compared to BD-S and HCs (p < 0.05, Bonferroni correction). Additionally, both BD + S and BD-S groups revealed decreased FA in the bilateral body and genu of corpus callosum (CC) compared to HCs (p < 0.05, Bonferroni correction). No significant correlation between plasma inflammatory cytokines and WM integrity was found. In the BD + S group, we found negative correlation between the scores of YMRS and FA values of the left middle cerebellar peduncle (r = −0.74, p = 0.035).ConclusionThe inflammation and impaired WM integrity may provide a scientific basis to understand the potential mechanisms of BD + S.

Subacute Sclerosing Panencephalitis: Restricted Diffusion and Clinical Evolution.

Subacute sclerosing panencephalitis (SSPE) is a rare entity characterized by a protracted course and progressive neurological deterioration. We present patterns of diffusion restriction in eight cases of SSPE, a seldom described imaging attribute. A retrospective analysis was performed on the clinical and neuroimaging data obtained from records of patients with proven SSPE. Patients whose magnetic resonance imaging (MRI) showed evidence of diffusion restriction were included in the analysis. MRI was performed on 3 T and 1.5-T clinical MR systems. Imaging characteristics were reviewed and tabulated by two neuroradiologists. Eight SSPE patients (seven men, one woman; age range: 5-15 years; mean age: 11 years) diagnosed and managed at our institute were included in the analysis. Restricted diffusion was evident in the basal ganglia (n = 3), corpus callosum (n = 2), white matter (n = 2) and in bilateral middle cerebellar peduncles (MCP) (n = 2). One patient had diffusion restriction in the genu of the corpus callosum and bilateral frontal cortical white matter. None of the diffusion-restricted lesions showed contrast enhancement or susceptibility. Six cases fulfilled the diagnostic criteria for fulminant SSPE (fSSPE). The extent of neuroparenchymal involvement was greater in this subset of patients. Restricted diffusion in SSPE, hitherto infrequently described, can indeed occur in both grey and white matter structures and in both supratentorial and infratentorial compartments. Parenchymal diffusion restriction in SSPE possibly reflects an early time point in the clinical evolution. A greater extent of parenchymal diffusion restriction may portend a rapid downhill course, possibly qualifying for fSSPE.

Regional White Matter Diffusion Changes Associated with the Cumulative Tensile Strain and Strain Rate in Nonconcussed Youth Football Players.

The purpose of this study is to assess the relationship between regional white matter diffusion imaging changes and finite element strain measures in nonconcussed youth football players. Pre- and post-season diffusion-weighted imaging was performed in 102 youth football subject-seasons, in which no concussions were diagnosed. The diffusion data were normalized to the IXI template. Percent change in fractional anisotropy (%ΔFA) images were generated. Using data from the head impact telemetry system, the cumulative maximum principal strain one times strain rate (CMPS1 × SR), a measure of the cumulative tensile brain strain and strain rate for one season, was calculated for each subject. Two linear regression analyses were performed to identify significant positive or inverse relationships between CMPS1 × SR and %ΔFA within the international consortium for brain mapping white matter mask. Age, body mass index, days between pre- and post-season imaging, previous brain injury, attention disorder diagnosis, and imaging protocol were included as covariates. False discovery rate correction was used with corrected alphas of 0.025 and voxel thresholds of zero. Controlling for all covariates, a significant, positive linear relationship between %ΔFA and CMPS1 × SR was identified in the bilateral cingulum, fornix, internal capsule, external capsule, corpus callosum, corona radiata, corticospinal tract, cerebral and middle cerebellar peduncle, superior longitudinal fasciculus, and right superior fronto-occipital fasciculus. Post hoc analyses further demonstrated significant %ΔFA differences between high-strain football subjects and noncollision control athletes, no significant %ΔFA differences between low-strain subjects and noncollision control athletes, and that CMPS1 × SR significantly explained more %ΔFA variance than number of head impacts alone.

Sequential pontine and bilateral cerebral peduncle infarction with resultant early Wallerian degeneration of the ponto‐cerebellar fibers

AbstractBilateral cerebral peduncular infarction (BCPI) is an extremely rare neurological disorder reportedly associated with locked‐in syndrome. A 60‐year‐old man represented with reduction in conscious level three weeks following a paramedian pontine infarction due to basilar artery thrombosis. Repeated MRI revealed subacute pontine infarction with new infarct involving bilateral cerebral peduncle. MRA showed absent flow‐related signal along the basilar artery consistent with occlusion. Additionally, Wallerian degeneration characterized by symmetrical hyperintense signal on MRI involving the ponto‐cerebellar fibers and both the middle cerebellar peduncles (MCPs) were seen. BCPI is an exceedingly rare type of stroke with characteristic symmetrical signal change involving the cerebral peduncles called “Mickey Mouse Ear” sign. Early Wallerian degeneration of the bilateral MCPs ensuing pontine infarction is also uncommon and is often detected incidentally and exhibits regular and symmetrical signal changes on MRI. Here, a rare encounter of early Wallerian degeneration following sequential pontine and BCPI is described.

MRI abnormality of the bilateral middle cerebellar peduncles and long‐term follow‐up in hypoglycemic encephalopathy: A case report

AbstractA 32‐year‐old woman had a medical history of a hypoglycemic attack. One year later, she had a second hypoglycemic attack. She could move her limbs after an intravenous glucose injection, but communication difficulty and cerebellar ataxia remained. We found brain MRI abnormalities in the bilateral middle cerebellar peduncles and internal capsule. The patient was diagnosed with insulinoma. High‐intensity MRI fluid‐attenuated inversion recovery at the bilateral middle cerebellar peduncles remained on the 45th day, but it disappeared after 1.7 years from the second attack. Consciousness improved, but cerebellar ataxia remained. The patient was able to walk without a cane following rehabilitation. There are few case reports of MRI abnormalities in the bilateral middle cerebellar peduncles in hypoglycemic encephalopathy. This case showed that infratentorial lesions, such as those in the middle cerebellar peduncles, might be observed on MRI in hypoglycemic encephalopathy that MRI abnormalities might disappear at long‐term follow‐up.

Hypertrophic olivary degeneration concomitant with bilateral middle cerebellar peduncles Wallerian degeneration following unilateral pontine infarction

BackgroundWallerian degeneration (WD) can occur in different projecting systems, such as corticospinal tract, dentate-rubro-olivary pathway, and corticopontocerebellar tract. However, the co-occurrence of hypertrophic olivary degeneration (HOD) and middle cerebellar peduncles (MCPs) degeneration secondary to unilateral pontine infarction in a single patient is extremely rare.Case presentationA 71-year-old man presented with acute onset of dizzness, slurred speech, and right-sided weakness. On the next day, his previous neurologic deficits deteriorated. Brain magnetic resonance imaging (MRI) revealed acute ischemic stroke of the left pons. After treatment with thrombolysis, antiplatelets, and rehabilitation training, his speaking and motor function improved moderately. At the 3-month follow-up, the MRI showed hyperintensity in the left medulla oblongata and bilateral MCPs on T2-weighted and FLAIR images, suggesting HOD as well as MCPs degeneration.ConclusionsIt is of great importance for us to know the anatomic knowledge of dentate-rubro-olivary and corticopontocerebellar pathways.

Outcomes at 6 months are related to brain structural and white matter microstructural reorganization in idiopathic tinnitus patients treated with sound therapy

This study aimed to explore brain structural and white matter microstructural reorganization in the early stage of tinnitus and identify brain alterations that contribute to its relief after 6 months of sound therapy. We studied 64 patients with idiopathic tinnitus, including 29 patients who were categorized into an effective group (EG) and 35 who were categorized into an ineffective group (IG) according to the 6‐month follow‐up improvement of the Tinnitus Handicap Inventory score, along with 63 healthy controls (HCs). All participants underwent structural and diffusion tensor imaging scanning on a 3‐T magnetic resonance system. Differences in brain gray/white matter volume and white matter microstructure were evaluated using voxel‐based morphometry analysis and tract‐based spatial statistics among the three groups. Associations between brain reorganization and the improvement of tinnitus symptoms were also investigated. Compared with EG patients, IG patients experienced a significant gray matter volume decrease in the right middle frontal gyrus (MFG)/right precentral gyrus (PreCG). Meanwhile, both EG and IG patients showed significant changes (decrease or increase) in brain white matter integrity in the auditory‐related or nonauditory‐related white matter fiber tracts compared with HCs, while EG patients showed decreased axial diffusivity in the bilateral middle cerebellar peduncle (MCP) compared with IG patients. We combined the gray matter change of the MFG/PreCG and the white matter integrity of the bilateral MCP as an imaging indicator to evaluate the patient's prognosis and screen patients before treatment; this approach reached a sensitivity of 77.1% and a specificity of 82.8%. Our study suggests that there was a close relationship between brain reorganization and tinnitus improvement. The right MFG/PreCG and bilateral MCP may be indicators that can be used to predict prognoses in patients with idiopathic tinnitus and may be used to screen patients before sound therapy. These findings may provide new useful information that can lead to a better understanding of the tinnitus mechanism.

The cerebellum in idiopathic cervical dystonia: A specific pattern of structural abnormalities?

IntroductionIn recent years, cerebellar abnormalities have gained increasing attention as possible physiopathological substratum of idiopathic cervical dystonia (ICD), but a consistent pattern of cerebellar structural modifications has not yet been established. We systematically investigated the presence of volumetric alterations of cerebellar gray (GM) and white matter (WM) in ICD patients, as well as their clinical relevance. MethodsIn this two-centers prospective cross-sectional study, from May 2013 to December 2017, 27 patients with ICD and 27 age- and sex-comparable healthy controls underwent brain MRI including 3D T1-weighted sequences for volumetric analyses. Between-group differences in terms of gray matter and cerebellar peduncles volumes were investigated using both region of interest (ROI)-based and voxel-based approaches using the SUIT tool (SPM12), and significant volumetric changes were correlated with clinical impairment (as measured with the Tsui score) and presence of tremor. ResultsICD patients showed significant volumetric reduction of cerebellar GM in the anterior lobe and lobule VI, resulting from both ROI-based (p ≤ 0.009) and voxel-based (p ≤ 0.04) analyses, while small clusters of reduced WM volume were found in the right cerebellum and left midbrain (p = 0.04), along with reduced volume of the bilateral superior (p = 0.04) and middle (p = 0.03) cerebellar peduncles. Furthermore, higher middle cerebellar peduncles volume was associated with the presence of tremor (p = 0.04). ConclusionOur data show evidence of a specific pattern of cerebellar structural abnormalities in ICD patients, with volume loss mainly involving cortical GM regions related to the somatotopic representation of the affected body parts and, to a lesser extent, cerebellar peduncles.

Bilateral middle cerebellar peduncle lesions: Neuroimaging features and differential diagnoses.

ObjectivesLesions limited to the bilateral middle cerebellar peduncles (MCPs) are uncommon. This retrospective study investigated diseases with a proclivity for the bilateral MCPs and explored the associations between their neuroimaging features and clinical findings for the differential diagnosis of such lesions.MethodsWe enrolled 26 patients who were admitted to our department between January 2016 and March 2019 with bilateral MCP abnormalities on magnetic resonance imaging (MRI). The demographic, clinical, and neuroimaging characteristics, and the biomarkers and diagnoses were evaluated.ResultsAlthough all patients exhibited symmetrical bilateral MCP hypointensities on T1‐weighted imaging and hyperintensities on T2‐weighted and fluid‐attenuated inversion recovery imaging, they were diagnosed with different conditions. Diagnoses included acute cerebral infarction (ACI) (n = 9, 34.62%), Wallerian degeneration (WD) (n = 8, 30.77%), multiple system atrophy (MSA) (n = 6, 23.08%), neuromyelitis optica (NMO) (n = 1, 3.85%), heroin‐induced leukoencephalopathy (n = 1, 3.85%), and primary central nervous system lymphoma (PCNSL) (n = 1, 3.85%). Patients with ACI exhibited bilateral MCP‐restricted diffusion hyperintensities on diffusion‐weighted imaging and corresponding stenosis or occlusion of the vertebrobasilar system. The initial MRI of patients with WD depicted pontine infarctions, while symmetrical MCP lesions were observed on follow‐up MRI. Symmetrical MCP lesions, cruciform hyperintensity, and marked atrophy in the posterior fossa were characteristic manifestations of MSA. Longitudinally extensive myelitis affecting more than three vertebral segments on cervical MRI and positive serum AQP4‐IgG may be indicative of NMO. Heroin‐induced leukoencephalopathy was characterized by extra‐symmetrical lesions in the posterior limbs of the internal capsules, while the anterior limbs were spared. PCNSL was indicated by a significant and characteristic “fist” sign on contrast‐enhanced MRI.ConclusionsBilateral MCP lesions were most frequently observed in cerebrovascular diseases, followed by neurodegenerative diseases, inflammatory diseases, toxic encephalopathies, and lymphomas. Our findings demonstrate that bilateral MCP signal abnormalities are more common in patients with ACI and WD, with fewer degenerative processes than previously believed. The high frequency of WD may be attributed to the specific awareness of this pathology. WD can also present with stage‐related restricted diffusion and should not be mistaken for a new infarction. The symmetrical bilateral MCP hypointensities on T1‐weighted imaging and hyperintensities on T2‐weighted imaging often raise concern regarding a demyelinating process. Our findings emphasize that neurologists should consider the aforementioned conditions and correlate the specific neuroimaging characteristics and medical history before arriving at the final diagnosis.

Evaluation of Clinical Features and Stroke Etiology in Patients with Bilateral Middle Cerebellar Peduncle Infarction

Objective: The aim of this study was to characterize clinical features, etiologies, and mechanisms of strokes due to bilateral middle cerebellar peduncle infarction (BMCPI). Methods: Cases diagnosed as BMCPI in our hospital were retrieved, and a literature review was performed. Data on clinical features and brain MRI were obtained. Extracranial and intracranial segments of the vertebrobasilar artery were assessed by using digital subtraction angiography, magnetic resonance angiography, or computed tomography angiography. Results: Thirteen cases (11 men and 2 women) of BMCPI were identified. A high-intensity signal of diffusion-weighted imaging sequence involving the bilateral middle cerebellar peduncle was observed in all patients. Most patients experienced vertigo, dysarthria, ataxia, and hearing disorders. Eleven of these cases were classified as large artery atherosclerosis, one as traumatic vertebral artery (VA) dissection, and one as giant cell arteritis. Conclusion: BMCPI is a rare cerebrovascular disease characterized by vertigo, ataxia, and dysarthria, which may also be accompanied by a hearing deficit or clinical signs of brainstem damage. BMCPI may be associated with hypoperfusion secondary to occlusive disease of the bilateral VA or proximal basilar artery.

A Chinese case of fragile X-associated tremor/ataxia syndrome (FXTAS) with orthostatic tremor:case report and literature review on tremor in FXTAS

BackgroundFragile X-associated tremor/ataxia syndrome (FXTAS) is a late onset, X-linked genetic, neurodegenerative disorder caused by a “premutation (PM)” in the fragile X mental retardation 1 (FMR1) gene. Here we report a case of FXTAS from mainland of China who presented with rare orthostatic tremor. A review of tremor of FXTAS in the literature is also included.Case presentationA 67-year-old right-handed farmer started with tremor of both legs 8 years ago which was present while standing but absent when sitting or lying and progressed with unsteady gait one and a half years ago. The brain MRI showed high intensity signal in the bilateral middle cerebellar peduncles (MCP) in T2-weighted and fluid-attenuated inversion recovery (FLAIR) images and gene test for premutation for FMR1 was positive with 101 CGG repeats. The patient met the the diagnosis of definite FXTAS. Clonazepam and topiramate were administered to control tremor. We reviewed the literature and identified 64 cases with detailed clinical and genetic information. Orthostatic tremor associated with FXTAS is very rare. We found 85.2% patients reported tremor,42.6% with intention tremor,36.1% with kinetic tremor,32.8% with rest tremor and 29.5% with posture tremor. 37.7% of patients who have tremor showed at least two types of tremor. There were 6 patients with isolated rest tremor. There was 2 patient with voice tremor and 6 with head tremor. We also found that 74.6% FXTAS patients had family history of FMR1 gene associated diseases including Fragile X syndrome (FXS), FXTAS or fragile X-associated primary ovarian insufficiency (FXPOI).ConclusionsAdding our data to the available literature suggests that orthostatic tremor could be a rare initial manifestation of FXTAS and the review will increasing our understanding the phenotype of tremor in FXTAS. Family history of FMR1 gene associated diseases might be an important clue to the diagnosis.

Identifying and characterizing projections from the subthalamic nucleus to the cerebellum in humans

A connection between the subthalamic nucleus (STN) and the cerebellum which has been shown to exist in non-human primates, was recently identified in humans. However, its anatomical features, network properties and function have yet to be elucidated in humans. In the present study, we quantified the STN-cerebellum pathway in humans and explored its function based on structural observations. Anatomical features and asymmetry index (AI) were explored using high definition fiber tractography data of 30 individuals from the Massachusetts General Hospital – Human Connectome Project adult diffusion database. Pearson’s correlation analysis was performed to determine the interrelationship between the subdivisions of the STN-cerebellum and the global cortical-STN connections. The pathway was visualized bilaterally in all the subjects. Typically, after setting out from the STN, the STN-cerebellum projections incorporated into the nearby corticopontine tracts, passing through the cerebral peduncle, mediated by the pontine nucleus and then connecting in two opposite directions to join the bilateral middle cerebellar peduncle. On the group averaged level, 78.03% and 62.54% of fibers from the right and left STN respectively, distributed to Crus I in the cerebellum, part of the remaining fibers projected to Crus II, with most of the fibers crossing contralaterally. According to the AI evaluation, 60% of the participants were right STN dominant, 23% were left STN dominant, and 17% were relatively symmetric. Pearson’s correlation analysis further indicated that the number of pathways from mesial Brodmann area 8 to the STN (hyperdirect pathway associated with decision making) was positively correlated with the number of fibers from the right STN to Crus I. The insertion and termination, the right-side dominance, and the positive correlation with the hyperdirect pathway all suggest that the STN-cerebellum pathway might be involved in decision-making processes.

Wallerian Degeneration of the Bilateral Middle Cerebella Peduncles Secondary to Unilateral Pontine Hemorrhage

The bilateral and symmetrical Wallerian degeneration (WD) of the middle cerebellar peduncles (MCPs) is rarely reported in pontine hemorrhage. We described a patient with WD of bilateral MCPs secondary to a strip of unilateral and transversal pontine hemorrhage. Magnetic Resonance Imaging showed hyperintensity on T2-weighted, fluid attenuation inversion recovery and diffusion weighted image, and hypointensity on T1-weighted and apparent diffusion co-efficient map, and no enhancement in bilateral MCPs. These abnormal signals existed over 6 months and subsided gradually. The patients didn’t present with new symptoms when WD happened, the initial clinical manifestations related to pontine hemorrhage persisted for more than one year. In conclusion, a single unilateral pontine stroke along “cross” or “trident” line may cause WD of the bilateral MCPs in the below slice. Although this pathological change brings no additional new symptoms, it is related to the short‑term of poor neurological prognosis after pontine stroke. In addition, since this lesion appears restricted diffusion in the imaging, we should avoid misdiagnosing it as new infarction