Left Cerebellar Hemisphere Research Articles

23. Cerebellum and attention: Eevidence from an Event-Related Potentials and transranial Direct Current Stimulation study

The role of the cerebellum extends beyond its traditional role in motor control. In recent years this structure has increasingly been seen as playing a crucial role also in cognitive performance and attentional processes being a subcortical structure that interacts with cortical brain areas. To investigate the role of the cerebellum in attentional processing of the stimulus, we studied the effects of transcranial Direct Current Stimulation (tDCS) delivered over the left cerebellar hemisphere on the ERPs components during a Novelty P300 task in healthy subjects. Fifteen healthy subjects underwent cathodal, anodal and sham tDCS sessions and a P300 Novelty was recorded task prior and after each tDCS session. Only cathodal cerebellar tDCS significantly reduced the amplitude and latency of the N1 component and reduced the amplitude of P3 components for both the target and novel stimuli. These results support the role for the cerebellum in the attentional processing of the stimulus. In particular, we speculate that the cerebellum acts indirectly by regulating and managing the activation and inhibition levels of the cortical areas that work in the attentional networks.

Voxel-based lesion symptom mapping analysis of depressive mood in patients with isolated cerebellar stroke: A pilot study.

Post-stroke depression (PSD) is the most common neuropsychological sequela of stroke and occurs in approximately one-third of all stroke survivors. However, there are no well-established predictors of PSD. Depression in stroke patients is correlated with unfavorable outcomes. Meta-analyses of the relationship between PSD and lesion location have yielded contradictory results and have not adequately addressed the impact of cerebellar lesions. Furthermore, other brain regions associated with depression in patients with cerebellar stroke remain a matter of debate. For these reasons, this cross-sectional study investigated the relationship between PSD and lesion location in patients with isolated cerebellar stroke.Twenty-four patients in the subacute rehabilitative period following a first-ever isolated cerebellar stroke were enrolled in the study. Depressive mood were evaluated using the Geriatric Depression Scale. Regions of interest were drawn manually on T1-weighted magnetic resonance images using MRIcron software, and data were normalized to a standard brain template in order to examine the neural correlates of depression using voxel-based lesion-symptom mapping analysis.Voxel-wise subtraction and χ (Ayerbe et al., 2014) analyses indicated that damage to the left posterior cerebellar hemisphere was associated with depression. Significant correlations were also found between the severity of depressive symptoms and lesions in lobules VI, VIIb, VIII, Crus I, and Crus II of the left cerebellar hemisphere (Pcorrected = 0.045). Our results suggest that damage to the left posterior cerebellum is associated with increased depressive mood severity in patients with isolated cerebellar stroke.

Complex Trajectories of Brain Development in the Healthy Human Fetus.

This study characterizes global and hemispheric brain growth in healthy human fetuses during the second half of pregnancy using three-dimensional MRI techniques. We studied 166 healthy fetuses that underwent MRI between 18 and 39 completed weeks gestation. We created three-dimensional high-resolution reconstructions of the brain and calculated volumes for left and right cortical gray matter (CGM), fetal white matter (FWM), deep subcortical structures (DSS), and the cerebellum. We calculated the rate of growth for each tissue class according to gestational age and described patterns of hemispheric growth. Each brain region demonstrated major increases in volume during the second half of gestation, the most pronounced being the cerebellum (34-fold), followed by FWM (22-fold), CGM (21-fold), and DSS (10-fold). The left cerebellar hemisphere, CGM, and DSS had larger volumes early in gestation, but these equalized by term. It has been increasingly recognized that brain asymmetry evolves throughout the human life span. Advanced quantitative MRI provides noninvasive measurements of early structural asymmetry between the left and right fetal brain that may inform functional and behavioral laterality differences seen in children and young adulthood.

Evidence of cellular stress and caspase-3 resulting from a combined two-frequency signal in the cerebrum and cerebellum of sprague-dawley rats.

Multiple simultaneous exposures to electromagnetic signals induced adjustments in mammal nervous systems. In this study, we investigated the non-thermal SAR (Specific Absorption Rate) in the cerebral or cerebellar hemispheres of rats exposed in vivo to combined electromagnetic field (EMF) signals at 900 and 2450 MHz.Forty rats divided into four groups of 10 were individually exposed or not exposed to radiation in a GTEM chamber for one or two hours. After radiation, we used the Chemiluminescent Enzyme-Linked Immunosorbent Assay (ChELISA) technique to measure cellular stress levels, indicated by the presence of heat shock proteins (HSP) 90 and 70, as well as caspase-3-dependent pre-apoptotic activity in left and right cerebral and cerebellar hemispheres of Sprague Dawley rats.Twenty-four hours after exposure to combined or single radiation, significant differences were evident in HSP 90 and 70 but not in caspase 3 levels between the hemispheres of the cerebral cortex at high SAR levels. In the cerebellar hemispheres, groups exposed to a single radiofrequency (RF) and high SAR showed significant differences in HSP 90, 70 and caspase-3 levels compared to control animals. The absorbed energy and/or biological effects of combined signals were not additive, suggesting that multiple signals act on nervous tissue by a different mechanism.

On the Effect of Sex on Prefrontal and Cerebellar Neurometabolites in Healthy Adults: An MRS Study.

In neuropsychiatric research, the aspects of sex have received increasing attention over the past decade. With regard to the neurometabolic differences in the prefrontal cortex and the cerebellum of both men and women, we performed a magnetic resonance spectroscopic (MRS) study of a large group of healthy subjects. For neurometabolic measurements, we used single-voxel proton MRS. The voxels of interest (VOI) were placed in the pregenual anterior cingulate cortex (pACC) and the left cerebellar hemisphere. Absolute quantification of creatine (Cre), total choline (t-Cho), glutamate and glutamine (Glx), N-acetylaspartate, and myo-inositol (mI) was performed. Thirty-three automatically matched ACCs and 31 cerebellar male–female pairs were statistically analyzed. We found no significant neurometabolic differences in the pACC region (Wilks' lambda: p = 0.657). In the left cerebellar region, we detected significant variations between the male and female groups (p = 0.001). Specifically, we detected significantly higher Cre (p = 0.005) and t-Cho (p = 0.000) levels in men. Additionally, males tended to have higher Glx and mI concentrations. This is the first study to report neurometabolic sex differences in the cerebellum. The effects of sexual hormones might have influenced our findings. Our data indicates the importance of adjusting for the confounding effects of sex in MRS studies.

Metástasis cerebelosa de carcinoma folicular de tiroides

We present here, for the first time, a case of cerebellar metastasis from a follicular thyroid carcinoma. A 78 year-old woman had undergone total thyroidectomy 23 years previously for an atypical thyroid adenoma in the left thyroid lobe. Serum thyroglobulin (tg) levels subsequently increased but thyroglobulin antibody levels were always negative. She received radioiodine therapy on several occasions. In the follow-up localizing study a whole body CT scan revealed an image at the left cerebellar hemisphere level. The patient underwent surgery for the cerebellar lesion and immunohistochemistry revealed it to be a metastasis of thyroid origin; the tumour cells had diffuse and intense positivity for cytokeratin-7 (CK7), thyroid transcription factor-1 (TTF-1) and tg, focal and weak positivity for CK19 and negativity for PGAF, galectin-3 and CK20. The analysis of V600K V600E BRAF gene mutations was negative.

Crossed Cerebellar Diaschisis in Convulsive Status Epilepticus

Background: Status epilepticus (SE) may be associated with increased intensity in the cerebral cortex as observed on diffusion-weighted and fluid-attenuated inversion recovery magnetic resonance imaging (MRI). Rarely, this change in intensity also occurs in the contralateral cerebellum, although the pathophysiology of this phenomenon in epilepsy is not fully understood. Here, we present a case of crossed cerebellar diaschisis in convulsive status epilepticus and discuss the changes in serial MRI findings. Case Report: A 48-year-old female patient was admitted to our hospital. She experienced an intermittent seizure every couple of months since infancy. One month before her admission, she discontinued the anticonvulsant medication by herself. On the admission day, she was found by her son in comatose mental status with a convulsive seizure involving the left side of the body. The seizure was controlled after administration of lorazepam and intravenous loading of levetiracetam. Brain MRI showed diffusion restriction in the right frontal lobe and left cerebellar hemisphere. The symptom of left hemiparesis persisted. Follow-up MRI was performed after 1 month, and it showed an atrophic change in the right hemisphere and diffuse cortical laminar necrosis with a mild atrophic change in the left cerebellar hemisphere. Conclusion: Our case, which showed high intensity in the right cerebral hemisphere and the contralateral cerebellum on diffusion-weighted imaging, developed permanent cerebral and cerebellar damage. Key Words: Status epilepticus; Crossed cerebellar diaschisis; Magnetic resonance imaging

LG-31SUCCESSFUL TREATMENT OF BRAINSTEM PILOMYXOID ASTROCYTOMA USING RECOMBINANT HUMAN ENDOSTATIN COMBINED WITH VINCRISTINE AND CARBOPLATIN: A CASE REPORT

LG-31. SUCCESSFUL TREATMENT OF BRAINSTEM PILOMYXOID ASTROCYTOMA USING RECOMBINANT HUMAN ENDOSTATIN COMBINED WITH VINCRISTINE AND CARBOPLATIN: A CASE REPORT Zhang Jun-Ping, Ge Jing-Jing, Li Cheng, Xue Feng-Jun, and Gao Zhi-Meng; Department of Neuro-Oncology, Sanbo Brain Hospital Capital Medical University, Beijing, China Brainstem glioma of children, especially recurrent pilomyxoid astrocytoma with CNS spread is neuro-oncology challenge. Recombinant human endostatin (rh-ES), an inhibitor of angiogenesis and tumor growth, has been used for treatment of lung cancer, but no experience for pilocytic astrocytoma. Here we report a case of recurrent pilomyxoid astrocytoma that was successfully treated using rh-ES in combination with vincristine (VCR) and carboplatin (CBP). A 12-year-old girl experienced difficulty in walking, dysphagia, bucking and coughing episodes and was diagnosed with a recurrent pilomyxoid astrocytoma in the medulla oblongata, with spreading of supprasellar region, left cerebellar hemisphere and the myelon. She firstly was received chemotherapy with VCR and CBP once a week. Three weeks later, her tumor was progressed and her clinical status deteriorated. Then she was started on rh-ES once per day, on a schedule of two weeks on, two weeks off, in combination with VCR and CBP. Two months after starting with rh-ES treatment, the enhancing mass was decreased. Four months later, the girl experienced improvement in clinical symptomsandsignificant decreaseof tumor. This case suggests that rh-ES may strengthen the effect of VCR and CBP on recurrent pilomyxoid astrocytoma with CNS spread. Neuro-Oncology 18:iii78–iii96, 2016. doi:10.1093/neuonc/now075.31 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Internal modeling of upcoming speech: A causal role of the right posterior cerebellum in non-motor aspects of language production

Some language processing theories propose that, just as for other somatic actions, self-monitoring of language production is achieved through internal modeling. The cerebellum is the proposed center of such internal modeling in motor control, and the right cerebellum has been linked to an increasing number of language functions, including predictive processing during comprehension. Relating these findings, we tested whether the right posterior cerebellum has a causal role for self-monitoring of speech errors. Participants received 1 Hz repetitive transcranial magnetic stimulation during 15 min to lobules Crus I and II in the right hemisphere, and, in counterbalanced orders, to the contralateral area in the left cerebellar hemisphere (control) in order to induce a temporary inactivation of one of these zones. Immediately afterwards, they engaged in a speech production task priming the production of speech errors. Language production was impaired after right compared to left hemisphere stimulation, a finding that provides evidence for a causal role of the cerebellum during language production. We interpreted this role in terms of internal modeling of upcoming speech through a verbal working memory process used to prevent errors.

Cerebellar involvement in essential tremor with and without resting tremor: A Diffusion Tensor Imaging study

ObjectiveEssential Tremor with resting tremor (rET) is a debated and poorly understood clinical phenotype. Converging evidences show that neurodegeneration of the cerebellum underlies the pathophysiology of ET, but it is not known if cerebellar changes also occurs in patients with rET. The aim of our study was to evaluate cerebellar microstructure in patients with ET with- (rET) and without resting tremor (ETwr) in comparison to healthy controls by MR Diffusion Tensor Imaging (DTI). MethodsWe studied 67 patients with ET (rET: 29 and ETwr: 38) and 39 age-matched healthy controls (HC). DTI was performed to measure fractional anisotropy (FA) and mean diffusivity (MD) of white and grey matter (WM, GM) in the entire cerebellum and in right and left cerebellar hemispheres. ResultsMD was significantly higher in the cerebellar GM of ET total group (10.39 ± 0.87) in comparison with HC (9.90 ± 0.71) (p = 0.0027). Interestingly, MD was significantly different when ETwr (10.48 ± 0.77) were compared with HC (p = 0.0017), whereas a trend toward significance were found between rET (10.29 ± 0.99) and HC (p = 0.067). No differences among groups were found in MD of cerebellar WM and in FA values neither in the WM nor in the GM. ConclusionOur results demonstrate the presence of microstructural changes in the cerebellum of patients with ET. It is noteworthy that rET showed intermediate values compared to HC and ETwr, suggesting that rET shares part of the pathophysiological mechanisms of ETwr, but cerebellar involvement seems do not fully account for rET. In addition to the cerebellar loops, other networks may play a role in rET pathophysiology.

Neurophysiological and neuroimaging changes (crossed cerebrocerebellar atrophy) after prolonged non-convulsive status epilepticus

A 33-year-old female patient suffering from epilepsy since the age of seven years (Figure 1) presented with left-sided hemipare-sis following non-convulsive status epilepticus (NCSE) (Figure 2). Neuroimaging showed a reduction in volume of the right cere-bral hemisphere and left cerebellar hemisphere (Figure 3). EEG showed asymmetry with right hemispheric slowing (Figure 4).NCSE can have deleterious effects on the CNS because of neuronal death after 30 to 60 minutes of continuous con-vulsive activity

Rapidly calcified all of multiple intracranial hemorrhages occurred in a patient with Chronic idiopathic thrombocytopenic purpura

We report a 38-year-old female patient with chronic idiopathic thrombocytopenic purpura (ITP) who occurred in rapidly calcified all of multiple intracranial hemorrhage (ICH) lesions. The patient was admitted with poor oral intake and confused mentality. Neurologic examination revealed drowsy consciousness but no motor weakness. She had been diagnosed ITP 5 years ago, however, she was not taking any medication at the time of presentation. Brain CT demonstrated that multiple ICHs, which were located in left frontal lobe, left temporal lobe and right cerebellar hemisphere. Platelet count was 10,000 cells/mm3. The patient was treated with conservative management, which included corticosteroids and platelet transfusion. Follow-up CT performed 12 days after the admission revealed that multiple ICHs were grossly resolving state. Interestingly, high attenuated lesions were seen all of multiple ICH sites, which were considered calcification. After 30 months after hemorrhage, follow-up brain CT showed prominent calcification of all of previous multiple ICH lesions. The patient was well- being state.

Combined Cerebellar Proton MR Spectroscopy and DWI Study of Patients with Friedreich's Ataxia.

Friedreich's ataxia (FRDA) is the commonest autosomal recessive ataxia, caused by GAA triplet expansion in the frataxin gene. Neuropathological studies in FRDA demonstrate that besides the primary neurodegeneration of the dorsal root ganglia, there is a progressive atrophy of the cerebellar dentate nucleus. Diffusion-weighted imaging (DWI) detected microstructural alterations in the cerebellum of FRDA patients. To investigate the biochemical basis of these alterations, we used both DWI and proton MR spectroscopy (1H-MRS) to study the same cerebellar volume of interest (VOI) including the dentate nucleus. DWI and 1H-MRS study of the left cerebellar hemisphere was performed in 28 genetically proven FRDA patients and 35 healthy controls. In FRDA mean diffusivity (MD) values were calculated for the same 1H-MRS VOI. Clinical severity was evaluated using the International Cooperative Ataxia Rating Scale (ICARS). FRDA patients showed a significant reduction of N-acetyl-aspartate (NAA), a neuroaxonal marker, and choline (Cho), a membrane marker, both expressed relatively to creatine (Cr), and increased MD values. In FRDA patients NAA/Cr negatively correlated with MD values (r = -0.396, p = 0.037) and with ICARS score (r = -0.669, p < 0.001). Age-normalized NAA/Cr loss correlated with the GAA expansion (r = -0.492, p = 0.008). The reduced cerebellar NAA/Cr in FRDA suggests that neuroaxonal loss is related to the microstructural changes determining higher MD values. The correlation between NAA/Cr and the severity of disability suggests that this biochemical in vivo MR parameter might be a useful biomarker to evaluate therapeutic interventions.

Effects of cerebellar transcranial direct current stimulation on attentional processing of the stimulus: Evidence from an event-related potentials study

Attentional processing consists of a set of processes that manage the flow of information through the nervous system and appropriately allocate attentional resources to relevant stimuli. Specific networks in the frontal and parietal regions appear to be involved in attention. The cerebellum has been identified as a subcortical structure that interacts with cortical brain areas, thereby controlling attentional processes.The aim of this study was to investigate the role of the cerebellum in attentional processing of the stimulus using a P300 Novelty task.We studied the effects of transcranial Direct Current Stimulation (tDCS) delivered over the left cerebellar hemisphere in cathodal, anodal and sham sessions on the P300 components in healthy subjects.Only cathodal cerebellar tDCS significantly reduced the amplitude of the N1, N2 and P3 components for both the target and novel stimuli. Moreover, N1 latency for all the stimuli was shorter after the cathodal tDCS session than after the sham or anodal sessions.These results point to a role of the cerebellum in attentional processing of the stimulus. The cerebellum may act indirectly by regulating and managing the activation and inhibition levels of the cortical areas involved in attentional networks.

A patient with complex multiple genomic ALK alterations

Lung cancer is a disease with a heterogeneous complement of mutations.1 Although point mutations and deletions are among the most common types of mutations in lung cancer, translocations in the...

Neuronal Substrates Underlying Performance Variability in Well-Trained Skillful Motor Task in Humans

Motor performance fluctuates trial by trial even in a well-trained motor skill. Here we show neural substrates underlying such behavioral fluctuation in humans. We first scanned brain activity with functional magnetic resonance imaging while healthy participants repeatedly performed a 10 s skillful sequential finger-tapping task. Before starting the experiment, the participants had completed intensive training. We evaluated task performance per trial (number of correct sequences in 10 s) and depicted brain regions where the activity changes in association with the fluctuation of the task performance across trials. We found that the activity in a broader range of frontoparietocerebellar network, including the bilateral dorsolateral prefrontal cortex (DLPFC), anterior cingulate and anterior insular cortices, and left cerebellar hemisphere, was negatively correlated with the task performance. We further showed in another transcranial direct current stimulation (tDCS) experiment that task performance deteriorated, when we applied anodal tDCS to the right DLPFC. These results indicate that fluctuation of brain activity in the nonmotor frontoparietocerebellar network may underlie trial-by-trial performance variability even in a well-trained motor skill, and its neuromodulation with tDCS may affect the task performance.

VEMP 所見異常と治療による回復を認めた中枢神経系脱髄疾患の一症例

Multiple sclerosis (MS) is characterized by multiple demyelinations within the central nervous system. It has been reported that patients with MS frequently have abnormal findings of cervical vestibular evoked myogenic potential (cVEMP) and ocular VEMP (oVEMP). We report the case of a patient with MS in whom cVEMP and oVEMP testing was useful for assessment of the lesions in the brainstem and their recovery. A 17-year-old woman presented with the feeling of light-headedness and a dull ache in the temple. MRI showed multiple T2-prolonged lesions, suggestive of demyelinated lesions in the left medulla oblongata, left superior cerebellar peduncle and left cerebellar hemisphere. One month after the MRI assessment, the patient's clinical findings worsened. She was diagnosed as having MS. Prior to the start of medical treatment, VEMP testing was performed. Air-conducted cVEMP showed a normal response to right ear stimulation, but decreased p13-n23 amplitudes and prolonged p13 latency in the left ear. Air-conducted oVEMP showed a normal amplitude, but prolonged N1 and P1 latencies in response to right ear stimulation, while there was no response to left ear stimulation. ABRs were normal. The patient was started on steroid pulse treatment, in response to which every T2-prolonged lesion in the MRI improved. Air-conducted cVEMP responses to left ear stimulation were restored to normal. Air-conducted sound oVEMPs showed normal amplitudes, but still slightly prolonged N1 and P1 latencies in response to right ear stimulation. oVEMP responses to left ear stimulation appeared after the treatment. According to the results of the first cVEMP and oVEMP testing, it was considered that lesions existed in the left MLF, vestibular nucleus and intramedullary vestibular nerve, while these structures on the right side were spared. The results of the testing for VEMPs were compatible with the MRI findings and the course of the MS. VEMP testing seems to be useful in the assessment of MS patients.

Is white matter affected in adolescents with anorexia nervosa? A study using magnetization transfer imaging

The aim of the study was to assess potential changes in structural integrity of the brain in adolescent patients with Anorexia Nervosa (AN) using the magnetization transfer imaging technique and re-evaluating after nutritional rehabilitation was accomplished. Magnetization transfer ratio (MTR) was used for the detection and quantification of histological changes to the white matter of 9 adolescents diagnosed with AN at diagnosis and after weight gain. Using the MTR technique 6 regions were measured: the pons, left cerebellar hemisphere, amygdala, thalamus, corona radiata and white matter adjacent to the left dorsolateral prefrontal cortex. Scans from the patients with AN were also compared with scans from an age-matched subset of 9 healthy controls. Compared with control subjects, the MTR of participants with AN was no different either at the early stages of diagnosis (p=0.62) or after weight recovery (p=0.81). Similarly, comparison of MTR between patients with AN at diagnoses compared with MTR after weight recovery yielded no statistically significant difference (P=0.33). We conclude that MTR was not able to detect any neuropathological alterations in adolescent patients with AN at either diagnosis or after nutritional recovery and the achievement of weight gain.

Papillary carcinoma thyroid with rare metastases: A case report and review

A 55-year-old female presented with a 10 years history of swelling in the front part of her neck, and a persistent headache for the past 4 months. During the course of her hospital stay, she developed right upper limb monoplegia. An examination showed that she had papillary carcinoma thyroid in an euthyroid state. Further work-up revealed a solitary pulmonary nodule on the left lower lobe, right ventricular tumor thrombus in the heart, and hemorrhagic metastases involving the left cerebral and cerebellar hemispheres. Total thyroidectomy with bilateral functional and central neck dissection was performed. Postoperatively, the patient received radioiodine ablation with I131 for lung and brain metastases, and remnant ablation for primary treatment. She has received regular follow-up care for the past 3 months.

RARE-19CASE REPORT OF THE NATURAL HISTORY OF INCIDENTALLY FOUND MEDULLOBLASTOMA FOLLOWED RADIOGRAPHICALLY IN A YOUNG ADULT WITH CHRONIC HEADACHES

Medulloblastoma is a malignant tumor diagnosed in 12-25% of pediatric brain tumors, 77% before the age of 19. In adulthood, the rate sharply declines with increasing age to be only diagnosed in 0.4-1% of adult brain tumors. These tumors are diagnosed typically after symptoms are noted consistent with increased intracranial pressure. We present a case of a young adult who was followed with serial MRI scans due to history of headaches and over time developed a lesion in the cerebellum that was later diagnosed as a medulloblastoma. We present this case as a natural history of medulloblastoma and will include a review of the literature. Patient AG had the original MRI brain scan for chronic headaches yielding only a right posterior fossa arachnoid cyst. Four years later, persistent headaches warranted another scan showing a new lesion with T2 FLAIR hyperintensity in the left cerebellar hemisphere. Serial scans over two years showed progression in size and complexity of this new lesion originally thought benign. AG underwent craniotomy with mass resection that resulted in cytoplasmic beta-catenin positive medulloblastoma without anaplasia on neuropathology. It was also without metastasis or CSF involvement. Post-operative imaging showed a small suspicious area near the resection cavity which biopsies later proved positive for residual medulloblastoma greater than 1.5 cm, thus placing this patient into the high-risk treatment category. AG elected proton therapy (36 in the craniospinal region with posterior fossa boost) with vincristine following protocol ACNS0331 with maintenance therapy afterward. AG has since been followed with serial MRI scans without evidence of residual disease. After reviewing the literature, low occurrences of incidental CNS tumors have been found in trauma and research cases. It is rare to have radiographic evidence of the onset of a malignant brain tumor. We present our case and literature review of this entity.