Infratentorial Structures Research Articles

Pilocytic Astrocytoma: A Review of General, Clinical, and Molecular Characteristics

Pilocytic astrocytomas are the primary tumors most frequently found in children and adolescents, accounting for approximately 15.6% of all brain tumors and 5.4% of all gliomas. They are mostly found in infratentorial structures such as the cerebellum and in midline cerebral structures such as the optic nerve, hypothalamus, and brain stem. The present study aimed to list the main characteristics about this tumor, to better understand the diagnosis and treatment of these patients, and was conducted on search of the published studies available in NCBI, PubMed, MEDLINE, Scielo, and Google Scholar. It was possible to define the main histologic findings observed in these cases, such as mitoses, necrosis, and Rosenthal fibers. We described the locations usually most affected by tumor development, and this was associated with the most frequent clinical features. The comparison between the molecular diagnostic methods showed great use of fluorescent in situ hybridization, polymerase chain reaction (PCR), and reverse transcriptase-PCR, important techniques for the detection of BRAF V600E mutation and BRAF-KIAA1549 fusion, characteristic molecular alterations in pilocytic astrocytomas.

MRI AS A TOOL OF DIFFERENTIAL DIAGNOSTIC IN THE BRAINSTEM DAMAGE IN CHILDREN

Summary. In this review magnetic resonance tomography (MRI) is presented as the tool for differential diagnostic in the brainstem damage in children. It is shown that the isolated or connected with supratentorial changes brainstems lesion occurs within a wide range of pathological conditions. Small size, less clear distinction between gray and white matter and the limit of visualization infratentorial structures with multiparametric MRI often lead to difficulties in the differential diagnosis. Sometimes the most important in the diagnostic is the topography of lesions and their signal intensity. Clinical data, the results of epidemiological and laboratory studies are primary importance for differential diagnosis of brainstem damages.

Foetal onset of EIF2B related disorder in two siblings: cerebellar hypoplasia with absent Bergmann glia and severe hypomyelination

Bi-allelic pathogenic variants in genes of the EIF2B family are responsible for Childhood Ataxia with Central nervous system Hypomyelination/Vanishing White Matter disease, a progressive neurodegenerative disorder of the central white matter. Only seven molecularly proven cases with antenatal onset have been reported so far. We report for the first time the neuropathological findings obtained from two foetuses harbouring deleterious variants in the EIF2B5 gene who presented in utero growth retardation and microcephaly with simplified gyral pattern that led to a medical termination of the pregnancy at 27 and 32 weeks of gestation. Neuropathological examination confirmed microcephaly with delayed gyration, periventricular pseudo-cysts and severe cerebellar hypoplasia. Histologically, the cerebellar cortex was immature, the dentate nuclei were fragmented and myelin stains revealed almost no myelination of the infratentorial structures. Bergmann glia was virtually absent associated to a drastic decreased number of mature astrocytes in the cerebellar white matter, multiple nestin-positive immature astrocytes as well as increased numbers of PDGRFα-positive oligodendrocyte precursors. Whole exome sequencing performed in the two foetuses and their parents allowed the identification of two EIF2B5 compound heterozygous variants in the two foetuses: c.468C > G p.Ile156Met and c.1165G > A p.Val389Met, the parents being heterozygous carriers. These variants are absent in the genome Aggregation Database (gnomAD r2.0.2). Contrary to the variant Ile156Met already described in a patient with CACH syndrome, the variant p.Val389Met is novel and predicted to be deleterious using several softwares. Neuropathological findings further expand the phenotypic spectrum of the disease that very likely occurs during early gestation and may manifest from the second half of pregnancy by a severe impairment of cerebral and cerebellar development.

SUITer: An Automated Method for Improving Segmentation of Infratentorial Structures at Ultra-High-Field MRI.

The advent of high and ultra-high-field MRI has significantly improved the investigation of infratentorial structures by providing high-resolution images. However, none of the publicly available methods for cerebellar image analysis has been optimized for high-resolution images yet. We present the implementation of an automated algorithm-SUITer (spatially unbiased infratentorial for enhanced resolution) method for cerebellar lobules parcellation on high-resolution MR images acquired at both 3 and 7T MRI. SUITer was validated on five manually segmented data and compared with SUIT, FreeSurfer, and convolutional neural networks (CNN). SUITer was then applied to 3 and 7T MR images from 10 multiple sclerosis (MS) patients and 10 healthy controls (HCs). The difference in volumes estimation for the cerebellar grey matter (GM), between the manual segmentation (ground truth), SUIT, CNN, and SUITer was reduced when computed by SUITer compared to SUIT (5.56 vs. 29.23 mL) and CNN (5.56 vs. 9.43 mL). FreeSurfer showed low volumes difference (3.56 mL). SUITer segmentations showed a high correlation (R2 = .91) and a high overlap with manual segmentations for cerebellar GM (83.46%). SUITer also showed low volumes difference (7.29 mL), high correlation (R2 = .99), and a high overlap (87.44%) for cerebellar GM segmentations across magnetic fields. SUITer showed similar cerebellar GM volume differences between MS patients and HC at both 3T and 7T (7.69 and 7.76 mL, respectively). SUITer provides accurate segmentations of infratentorial structures across different resolutions and MR fields.

An Anatomic Study of the Keyhole Supra-Tentorium to Infra-Tentorium Endoscope Approach.

To provide anatomic basis for the retrosigmoid supra-tentorium to infra-tentorium keyhole approach and to explore the feasibility, 60 skulls were observed and measured to demonstrate the position relations among related bony landmarks, 12 cadaveric heads were dissected and measured for localization of the keyhole and the incision through tentorium. For giving the angle and depth for endoscopic approach, 40 adult volunteers were performed head MRI scan and the pictures were measured and analyzed. The surface projection of sigmoid and transverse sinus can be positioned by mastoidale, external occipital protuberance, and anterior end of parietomastoid suture (AEPMS) on body. There is a safe trigone of cerebellar tentorium (STCT) among inner edge of upper curve of sigmoid sinus, entrance of tentorial sinus/vein and midpoint of posterior edge of temporal arcuate eminence. 15 mm superior to the midpoint between asterion and AEPMS can be recognized as the central point of the keyhole. Magnetic resonance imaging pictures show there is potential subarachnoid space for endoscopic approach from the indicated keyhole to pontocerebellar trigone. This study demonstrated endoscopy can arrive at pontocerebellar trigone through the STCT and the keyhole supra-tentorium to infra-tentorium endoscope approach is feasible in anatomy and will contribute to excise lesions involving both supra- and infra-tentorial structures.

Cerebellar mutism: the predictive role of preoperative language evaluation.

The association between preoperative language impairment and development of cerebellar mutism after surgical treatment of posterior fossa tumors has gained increasing interest in recent years based on the concept that both local compression/infiltration of the infratentorial periventricular anatomical structures involved in speech and language, as well as an increased distraction of supratentorial periventricular anatomical structures, due to an associated hydrocephalus, involved in the coordination of speech circuits, might lead to the subclinical presence of language disturbances already at diagnosis, predicting the development of a cerebellar mutism syndrome after tumor removal. A thorough review of the literature on the subject has been performed, together with a review of our institutional experience reporting the related long-term (10years) results. According to our institutional experience, 20/70 (28.5%) children presented preoperative language impairment and developed cerebellar mutism after surgery. A residual impairment persists in 75% of the cases at a follow-up of 2years, and in 50% of the cases at 10years, a finding which actually depicts cerebellar mutism no more as a transient deficit but among long-term sequelae. The appearance of complex dysarthria in the postoperative period is a negative prognostic factor for the long-term persistence of speech disturbances.

Nystagmus-associated imaging signatures in Multiple Sclerosis: evaluation of subcortical and infratentorial structures (P5.2-050)

Nystagmus-associated imaging signatures in Multiple Sclerosis: evaluation of subcortical and infratentorial structures (P5.2-050)

Panencephalitis in children in modern conditions: clinical, etiological and mri-aspects

To characterize the clinical picture, infectious etiology and MRI results of panencephalitis (PANE) in children, depending on the duration of the disease. Children (n=32) with PANE at the age from 3 months up to 17 years were examined for a group of actual viral and bacterial infections. The inclusion criterion was a diffuse lesion of white matter hemispheres on MRI. MRI of the brain and spinal cord, CSF study (pleocytosis, oligoclonal IgG, the main myelin protein (MBP) were performed. The follow-up was 5-10 years. The complex therapy included etiotropic (antiviral) and pathogenetic agents, with priority given to cytoflavin as a drug with a multimodal effect. In 84.4% of cases, PANE in children are recorded under the age of 3 years and in 71.9% of cases, are associated with congenital infections with the prevalence of herpes viruses, especially cytomegalovirus (37,8%) and herpes type 6 (21.9%). In 78.3% of cases, PANE have chronic gradual development more often with a delay in the formation of motor and speech/prespeech skills, and manifested with pyramidal, cerebellar and other symptoms in the future. PANE is accompanied by a lesion of the white matter of the hemispheres in 1/2 cases with periventricular localization, less often in infratentorial structures (46.9%) and spinal cord (21.9%). With the duration of symptoms up to 3 months (n=22) PANE are characterized by inflammatory-demyelinating changes, signs of mass effect, contrast+, pleocytosis in CSF and the increase in MBP (average 4.2±0.8 ng/ml), and, with the duration of more than 3 months, by degenerative-sclerosing changes (n=10) and CSF oligoclonal IgG in 90% of cases. In almost 2/3 of cases, PANE are associated with congenital infections, accompanied by extensive symmetrical foci of demyelination in the CNS, and their clinical and laboratory parameters and outcomes depend on the start of treatment, with the positive dynamics in 75% of cases.

Track density imaging in progressive supranuclear palsy: A pilot study.

Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by white matter (WM) changes in different supra- and infratentorial brain structures. We used track density imaging (TDI) to characterize WM microstructural alterations in patients with PSP-Richardson's Syndrome (PSP-RS). Moreover, we investigated the diagnostic utility of TDI in distinguishing patients with PSP-RS from those with Parkinson's disease and healthy controls (HC). Twenty PSP-RS patients, 21 PD patients, and 23 HC underwent a 3 T MRI diffusion-weighted (DW) imaging. Then, we combined constrained spherical deconvolution and WM probabilistic tractography to reconstruct track density maps by calculating the number of WM streamlines traversing each voxel. Voxel-wise analysis was performed to assess group differences in track density maps. A support vector machine (SVM) approach was also used to evaluate the performance of TDI for discriminating between groups. Relative to PD patients, decreases in track density in PSP-RS patients were found in brainstem, cerebellum, thalamus, corpus callosum, and corticospinal tract. Similar findings were obtained between PSP-RS patients and HC. No differences in TDI were observed between PD and HC. SVM approach based on whole-brain analysis differentiated PD patients from PSP-RS with an area under the curve (AUC) of 0.82. The AUC reached a value of 0.98 considering only the voxels belonging to the superior cerebellar peduncle. This study shows that TDI may represent a useful approach for characterizing WM alterations in PSP-RS patients. Moreover, track density decrease in PSP could be considered a new feature for the differentiation of patients with PSP-RS from those with PD.

Validity of venous phase delay assessment in balloon occlusion test of internal carotid artery.

The aim of the present study was to investigate the utility of venous phase delay assessment to evaluate the balloon occlusion test (BOT) of the internal carotid artery (ICA). A total of 38 patients who received BOT of the ICA were included in this retrospective study. Clinical examination and venous phase assessment were performed in all patients to evaluate their suitability for the evaluation of the BOT of the ICA. The venous phase delay assessment compared the venous phase of supratentorial and infratentorial structures between hemispheres. Venous phase delay was defined as the time lag for opacification of the first cortical vein between the occluded hemisphere and the hemisphere examined. The results of the clinical examination and the venous phase delay assessment were compared. In most patients negative on clinical examination, the venous phase delay was no more than 2 sec, while for most patients positive on clinical examination, the delay was >2 sec. All patients with a venous phase delay of >4 sec had a positive clinical result. The present results indicated that venous phase delay assessment is a reliable method for evaluating BOT of the ICA, and in those with a delay of <2 sec, parent vessel occlusion of the ICA, which may be used as a pre-operative procedure prior to tumor resection for patients suffering from neck or skull-base tumors, was considered safe.

Stridor-related gray matter alterations in multiple system atrophy: A pilot study

IntroductionThe neuroanatomical substrate of stridor associated with Multiple System Atrophy (MSA) remains unclear. We evaluated stridor-related gray matter (GM) changes in MSA. Methods36 MSA patients underwent standardized nocturnal video-polysomnography and brain MRI. Differences in GM density between MSA patients with and without stridor and a sample of 22 matched healthy controls were evaluated with Voxel Based Morphometry protocol supplemented by a specific tool (SUIT) for analysing infratentorial structures. ResultsStridor was confirmed in 14 patients (10 MSA-cerebellar variant; 10 M; mean ± SD age = 61.6 ± 8.9years; disease duration = 5.2 ± 2.9years) and absent in 22 (11 MSA-cerebellar variant; 18 M; age = 61.4 ± 9.9years; disease duration = 4.8 ± 3.4years). Compared to MSA without stridor, patients with stridor showed higher GM density in the cerebellum (p < 0.05, corrected for the MSA-cerebellar variant and uncorrected when considering both MSA-variants) and lower in the striatum (p < 0.05, uncorrected). ConclusionsThis preliminary study has demonstrated for the first time in MSA stridor-related GM changes in striatal and cerebellar regions. Abnormalities in these regions were previously reported in dystonic disorders affecting laryngeal muscles, suggesting the hypothesis that stridor pathophysiology is dystonia-related. These results need however to be confirmed in a larger sample of patients.

Structural signature of SCA3: From presymptomatic to late disease stages.

Machado-Joseph disease (SCA3/MJD) is the most frequent spinocerebellar ataxia worldwide and characterized by brainstem, basal ganglia, and cerebellar damage. However, little is known about the natural history of the disease. This motivated us to determine the extension and progression of central nervous system involvement in SCA3/MJD using multimodal magnetic resonance imaging (MRI)-based analyses in a large cohort of patients (n = 79) and presymptomatic subjects (n = 12). All subjects underwent MRI in a 3T device to assess gray and white matter. To evaluate the cerebral and cerebellar cortices, we used measures from FreeSurfer and SUIT. T1-multiatlas assessed deep gray matter. Diffusion tensor imaging multiatlas was used to investigate cerebral white matter (WM) and SpineSeg to assess the cervical spinal cord. There was widespread WM and cerebellar damage, in contrast to the restricted motor cortex involvement when all patients are compared to age- and sex-matched controls. Presymtomatic patients showed WM microstructural abnormalities mainly in the cerebellar and cerebral peduncles and volumetric reduction of midbrain, spinal cord, and substantia nigra. To assess the disease progression, we divided patients into four subgroups defined by time from ataxia onset. There was a clear pattern of evolving structural compromise, starting in infratentorial structures and progressing up to the cerebral cortex. Structural damage in SCA3/MJD begins in the spinal cord, cerebellar peduncles, as well as substantia nigra and progresses to cerebral areas in the long term. These structural differences reveal some insights into the pathogenesis of SCA3/MJD and suggest a staging scheme to map the progression of the disease. Ann Neurol 2018;84:401-408.

Can cerebellar and brainstem apparent diffusion coefficient (ADC) values predict neuromotor outcome in term neonates with hypoxic-ischemic encephalopathy (HIE) treated with hypothermia?

Background and purposeTo determine the apparent diffusion coefficient (ADC) in specific infratentorial brain structures during the first week of life and its relation with neuromotor outcome for Hypoxic-ischemic encephalopathy (HIE) in term neonates with and without whole-body hypothermia (TH).Materials and methodsWe retrospectively evaluated 45 MRI studies performed in the first week of life of term neonates born between 2010 and 2013 at Boston Children's Hospital. Selected cases were classified into three groups: 1) HIE neonates who underwent TH, 2) HIE normothermics (TN), and 3) controls. The neuromotor outcome was categorized as normal, abnormal and death. The ADCmean was calculated for six infratentorial brain regions.ResultsA total of 45 infants were included: 28 HIE TH treated, 8 HIE TN, and 9 controls. The mean gestational age was 39 weeks; 57.8% were male; 11.1% were non-survivors. The median age at MRI was 3 days (interquartile range, 1–4 days). A statistically significant relationship was shown between motor outcome or death and the ADCmean in the vermis (P = 0.002), cerebellar left hemisphere (P = 0.002), midbrain (P = 0.009), pons (P = 0.014) and medulla (P = 0.005). In patients treated with TH, the ADC mean remained significantly lower than that in the controls only in the hemispheres (P = 0.01). In comparison with abnormal motor outcome, ADCmean was lowest in the left hemisphere (P = 0.003), vermis (P = 0.003), pons (P = 0.0036) and medulla (P = 0.008) in case of death.ConclusionADCmean values during the first week of life in the left hemisphere, vermis, pons and medulla are related to motor outcome or death in infants with HIE either with or without hypothermic therapy. Therefore, this objective tool can be assessed prospectively to determine if it can be used to establish prognosis in the first week of life, particularly in severe cases of HIE.

Neuroimaging findings in Joubert syndrome with C5orf42 gene mutations: A milder form of molar tooth sign and vermian hypoplasia

PurposeLittle is known regarding neuroimaging-genotype correlations in Joubert syndrome (JBTS). To elucidate one of these correlations, we investigated the neuroimaging findings of JBTS patients with C5orf42 mutations. Materials and methodsNeuroimaging findings in five JBTS patients with C5orf42 mutations were retrospectively assessed with regard to the infratentorial and supratentorial structures on T1-magnetization prepared rapid gradient echo (MPRAGE), T2-weighted images, and color-coded fractional anisotropy (FA) maps; the findings were compared to those in four JBTS patients with mutations in other genes (including three with AHI1 and one with TMEM67 mutations). ResultsIn C5orf42-mutant patients, the infratentorial magnetic resonance (MR) images showed normal or minimally thickened and minimally elongated superior cerebellar peduncles (SCP), normal or minimally deepened interpeduncular fossa (IF), and mild vermian hypoplasia (VH). However, in other patients, all had severe abnormalities in the SCP and IF, and moderate to marked VH. Supratentorial abnormalities were found in one individual in other JBTS. In JBTS with all mutations, color-coded FA maps showed the absence of decussation of the SCP (DSCP). ConclusionThe morphological neuroimaging findings in C5orf42-mutant JBTS were distinctly mild and made diagnosis difficult. However, the absence of DSCP on color-coded FA maps may facilitate the diagnosis of JBTS.

Leucoencephalopathy following abuse of sniffed heroin

A 29-year-old man was admitted for acute cognitive impairment. Three weeks earlier, he had been admitted for coma due to sniffed heroin abuse responsive to naloxone infusion. At admission, the patient presented with apraxia, severe memory impairment and anosognosia. Brain MRI revealed symmetric hyperintensities of supratentorial white matter, sparing brainstem and cerebellum, on FLAIR and B1000 sequences. Four months later, repeated neuropsychological assessment revealed dramatic improvement of global cognitive functions.Toxic leucoencephalopathy excluding the cerebellum and brainstem is a rare complication of heroin abuse, and seems to concern especially patients that use heroin by sniff or injection. In these patients, cognitive troubles are predominant, prognosis seems better and infratentorial brain structures can be spared.In conclusion, our observation emphasizes that heroin-induced encephalopathy can have a favourable outcome and that imaging and clinical patterns can indicate the mode of drug administration.

P08.34 Overall survival of primary high-grade gliomas of supra- and infratentorial midline structures

AbstractObjective:In literature recent and roubust data on the prognosis of patients with high grade gliomas (HGG) of WHO III° and IV° stratified by resectability, molecular features and different treatment modalities are available. However, little is known about outcome of patients with HGG´s located in supra- and infratentorial midline structures like corpus callosum, basal ganglia and brainstem. In this study we evaluate overall survival (OS) and influencing factors of patients with de novo HGG specifically in those structures.Patients and Methods:In a single center retrospective analysis we screened our database for all adult patients with primary HGG in midline structures diagnosed by stereotactic biopsy (SB) between January 1996 and March 2015. We evaluated OS and analyzed factors (MGMT status, treatment after SB, age, gender, Karnofsky Score (KPS), localization) influencing OS using Whitney-Mann-U and Chi-square test as well as cox regression analysis.Results.122 patients with HGG receiving stereotactic biopsy procedures (median age: 56.3 (22–82) years; median KPS: 80 (50–100)%. Histology revealed glioma WHO III° in 31.1% and WHO IV° in 68.9%. Lesions were localized in corpus callosum (50.0%), basal ganglia (18.9%), thalamus (9.0%), pineal region (2.5%), sella (0.8%), brainstem (18.9%). Median overall survival (mOS) was 6.3 months (95% CI, 3.6–9.0%), for WHO III°: 13.6 months (95% CI 5.6–21.6) and WHO IV°: 4.9 months (95 % CI, 3.2–6.6). Patients were treated as follows: no specific tumor therapy (13.1%, 2 WHO III° and 15 WHO IV°; mOS 1.1 months) or various Tumor specific therapy regimens (WHO III° 34 (32.4%) patients mOS 15.5 month [95% CI 7.4–23.6]), (WHO IV° 65 (61.9%) patients mOS 10.6 months). In 6 patients (5.7%) the type of adjuvant therapy is unknown. MGMT promotor methylation status was available for 46 tumor treated patients (18 WHO III°, 28 WHO IV°). mOS of patients with WHO IV tumors was significantly worse than WHO III° (p<0.0001). Any tumor specific treatment improved survival significantly (p=0.005). Poor condition (KPS<70) and no tumor specific therapy were the significant factors for poor OS in multivariate analysis (adjusted HR 1.88 CI95% 1.03–3.92 p=0.04 and 11.09 CI95% 5.24–23.35 p<0.0001 respectively).Conclusion:Overall survival de novo HGG’s especially of WHO IV located in midline structures is poor. Specific tumor treatment improves survival significantly. Treatment decision should be based on the patient’s clinical status for the best quality of life.

Brain morphometry in Pontocerebellar Hypoplasia type 2.

BackgroundPontocerebellar hypoplasia type 2 (PCH2) is caused by a defect in the TSEN54-gene and leads to severe and early disruption of brain development, especially of cerebellum and pons. The aim of this work was to quantify the infra- and supratentorial brain growth during postnatal brain development in children with PCH2.MethodsMRI data of 24 children with PCH2 (age 0.02–17 years., 13 females) were analysed volumetrically and compared to images of 24 typically developing age- and gender-matched children. All children with PCH2 had the homozygous p.A307S mutation in the TSEN54-gene. In 5 patients follow-up MRI investigations were available.Images of the children with PCH2 were available either on film (n = 12) or in digital format (n = 21). Images on film were digitalized. Brain structures were manually masked and further adjusted semi-automatically using intensity thresholding to exclude CSF. Volumes of cerebellum, brain stem, and pons were measured, as well as supratentorial brain and frontal lobe volume. For validation of the method part of the digital images were processed as images on film. In addition, intra- and inter-rater variabilities were tested.ResultsChildren with PCH2 showed reduced volumes of all measured brain structures compared to healthy controls. Severely hypoplastic cerebellum, pons and brain stem only slightly increased in size postnatally. Supratentorial brain volume also showed reduced growth compared to the healthy controls. Differences between patients and controls could already be seen at birth but became more significant during childhood. Validation of the method showed high precision and reproducibility.ConclusionsIn a genetically very homogenous group of children with PCH2 severely hypoplastic infratentorial structures, the hallmark of the disease, showed only slight increase in volume postnatally. Supratentorial brain structures, which are considered normal at birth, also showed smaller volumes neonatally and a lower growth rate compared to controls, leading to severe microcephaly. Volume loss, however, could not be observed during the first years of life. This argues for a severe disruption of the cerebellar-cerebral networks during pre- and postnatal development caused by a primary cerebellar dysfunction, rather than postnatal neurodegeneration. The developmental progress in these children, although little, further supports this.Electronic supplementary materialThe online version of this article (doi:10.1186/s13023-016-0481-4) contains supplementary material, which is available to authorized users.

Cerebellar Dysfunction and Ataxia in Patients with Epilepsy: Coincidence, Consequence, or Cause?

Basic epilepsy teachings assert that seizures arise from the cerebral cortex, glossing over infratentorial structures such as the cerebellum that are believed to modulate rather than generate seizures. Nonetheless, ataxia and other clinical findings in epileptic patients are slowly but inevitably drawing attention to this neural node. Tracing the evolution of this line of inquiry from the observed coincidence of cerebellar atrophy and cerebellar dysfunction (most apparently manifested as ataxia) in epilepsy to their close association, this review considers converging clinical, physiological, histological, and neuroimaging evidence that support incorporating the cerebellum into epilepsy pathology. We examine reports of still controversial cerebellar epilepsy, studies of cerebellar stimulation alleviating paroxysmal epileptic activity, studies and case reports of cerebellar lesions directly associated with seizures, and conditions in which ataxia is accompanied by epileptic seizures. Finally, the review substantiates the role of this complex brain structure in epilepsy whether by coincidence, as a consequence of deleterious cortical epileptic activity or antiepileptic drugs, or the very cause of the disease.

A Rare Cause of Dizziness and Gait Ataxia: CLIPPERS Syndrome.

In this paper we report the case of a 52-year-old woman with multiple contrast enhancing lesions associated with a chronic lymphocytic inflammation of the infratentorial structures. We discuss the symptoms, imaging and treatment of this rare disorder, in which magnetic resonance imaging (MRI) has a crucial role in the diagnosis. Early recognition on MRI and radiological follow-up are also important to optimize the treatment.

Accuracy of MR markers for differentiating Progressive Supranuclear Palsy from Parkinson's disease.

BackgroundAdvanced brain MR techniques are useful tools for differentiating Progressive Supranuclear Palsy from Parkinson's disease, although time-consuming and unlikely to be used all together in routine clinical work. We aimed to compare the diagnostic accuracy of quantitative morphometric, volumetric and DTI metrics for differentiating Progressive Supranuclear Palsy-Richardson's Syndrome from Parkinson's disease.Methods23 Progressive Supranuclear Palsy-Richardson's Syndrome and 42 Parkinson's disease patients underwent a standardized 1.5T brain MR protocol comprising high-resolution T1W1 and DTI sequences. Brainstem and cerebellar peduncles morphometry, automated volumetric analysis of brain deep gray matter and DTI metric analyses of specific brain structures were carried out. We determined diagnostic accuracy, sensitivity and specificity of MR-markers with respect to the clinical diagnosis by using univariate receiver operating characteristics curve analyses. Age-adjusted multivariate receiver operating characteristics analyses were then conducted including only MR-markers with a sensitivity and specificity exceeding 80%.ResultsMorphometric markers (midbrain area, pons to midbrain area ratio and MR Parkinsonism Index), DTI parameters (infratentorial structures) and volumetric analysis (thalamus, putamen and pallidus nuclei) presented moderate to high diagnostic accuracy in discriminating Progressive Supranuclear Palsy-Richardson's Syndrome from Parkinson's disease, with midbrain area showing the highest diagnostic accuracy (99%) (mean ± standard deviation: 75.87 ± 16.95 mm2vs 132.45 ± 20.94 mm2, respectively; p < 0.001).ConclusionAlthough several quantitative brain MR markers provided high diagnostic accuracy in differentiating Progressive Supranuclear Palsy-Richardson's Syndrome from Parkinson's disease, the morphometric assessment of midbrain area is the best single diagnostic marker and should be routinely included in the neuroradiological work-up of parkinsonian patients.