Evaluation of deep gray matter volume, cortical thickness and white matter integrity in patients with typical absence epilepsy: a study using voxelwise-based techniques.

INTRODUCTION: The objective of this study was to evaluate the cortical thickness and the volume of deep gray matter structures, measured from 3D T1-weighted gradient echo imaging, and white matter integrity, by diffusion tensor imaging (DTI) in patients with typical absence epilepsy (AE). METHODS: Patients (n = 19) with typical childhood AE and juvenile AE, currently taking antiepileptic medication, were compared with control subjects (n = 19), matched for gender and age. 3D T1 magnetization-prepared rapid gradient echo-weighted imaging and DTI along 30 noncolinear directions were performed using a 1.5-T MR scanner. FreeSurfer was used to perform cortical volumetric reconstruction and segmentation of deep gray matter structures. For tract-based spatial statistics analysis of DTI, a white matter skeleton was created, along with a permutation-based inference with 5000 permutations. A threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The mean, radial, and axial diffusivities were also projected onto the mean FA skeleton. RESULTS: Patients with AE presented decreased FA and increased mean diffusivity and radial diffusivity values in the genu and the body of the corpus callosum and right anterior corona radiata, as well as decreased axial diffusivity in the left posterior thalamic radiation, inferior cerebellar peduncle, right cerebral peduncle, and right corticospinal tract. However, there were no significant differences in cortical thickness or deep gray matter structure volumes between patients with AE and controls. CONCLUSION: Abnormalities found in white matter integrity may help to better understand the pathophysiology of AE and optimize diagnosis and treatment strategies.

Virtual bronchoscopy for evaluating cervical tumors of the fetus.

We report on four cases of fetal cervical tumor, comprising three lymphangiomas and one teratoma, evaluated by ultrasound and magnetic resonance imaging (MRI) between 26 and 37 weeks' gestation. The aim was to investigate the use of virtual bronchoscopy to evaluate fetal airway patency in each case. A three-dimensional (3D) model of the airway was created from overlapping image layers generated by MRI. The files obtained were manipulated using 3D modeling software, allowing the virtual positioning of observation cameras, adjustment of lighting parameters and creation of simulated 3D movies for analysis of a virtual path through the model. In all fetuses, fetal airway patency was clearly demonstrated by virtual bronchoscopy and this was confirmed postnatally. MRI with virtual bronchoscopy could become a useful tool for studying fetal airway patency in cases of cervical tumor.

Additive manufacturing models of fetuses built from three-dimensional ultrasound, magnetic resonance imaging and computed tomography scan data.

OBJECTIVE: To generate physical fetal models using images obtained by three-dimensional ultrasonography (3DUS), magnetic resonance imaging (MRI) and computed tomography (CT) to guide additive manufacturing technology. METHODS: Images from 33 fetuses, including three sets of twins, were used. Fifteen fetuses were normal and evaluated only by 3DUS. Eighteen cases had abnormalities such as conjoined twins, tumors, aneuploidy, skeletal abnormalities, central nervous system abnormalities and facial or thoracic defects. Scans were performed using high-resolution 3DUS. In cases of abnormalities, MRI and CT were performed on the same day as 3DUS. The images obtained with 3DUS, CT or MRI were exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high-definition screen. Software that converts medical images into numerical models was used to construct virtual 3D models, which were physically realized using additive manufacturing technologies. RESULTS: Physical models based on 3DUS, MRI and CT images either separately or combined were successfully generated. They were remarkably similar to the postnatal appearance of the aborted fetus or newborn baby, especially in cases with pathology. CONCLUSION: The use of 3DUS, MRI and CT may improve our understanding of fetal anatomical characteristics, and these technologies can be used for educational purposes and as a method for parents to visualize their unborn baby. The images can be segmented and applied separately or combined to construct 3D virtual and physical models.

Rhodococcus equi pneumonia in AIDS: high-resolution CT findings in five patients.

The aim of this study was to describe the high-resolution CT scan findings in five patients with AIDS and pulmonary infection due to Rhodococcus equi. The study included five patients with AIDS and proven R. equi infection. The CT scans were reviewed by two observers. The patients included four men and one woman ranging from 39 years to 49 years in age (mean 42 years). The findings included areas of consolidation (n=5) with single (n=1) or multiple cavitation (n=4), ground-glass opacities (n=5), centrilobular nodules (n=3), small centrilobular nodular opacities (n=3) and "tree in bud" opacities (n=3). None of the patients had pleural effusion or lymph node enlargement. The most common high-resolution CT manifestations of R. equi infection consist of areas of consolidation with cavitation, ground-glass opacities, nodules and a tree-in-bud pattern.

Intracranial hemorrhage following bone marrow transplantation: an autopsy study of 58 patients.

Autopsy files of 180 patients were reviewed, who died after BMT between July 1987 and June 1998 and 58 (32.2%) cases, who had experienced intracranial hemorrhage (ICH) were selected. Age, sex, underlying disease, preparatory regimens, immunoprophylaxis, chronic and acute GVHD, survival of the patients and localization and size of hemorrhages were evaluated. There were 33 males and 25 females, with a mean age of 23.4 years. The main underlying disorders for which BMT was performed included SAA (n = 21), CML (n = 13) and AML (n = 10). Forty patients were found to have intraparenchymal hemorrhage, 35 had subarachnoid hemorrhage and eight patients had subdural hemorrhage. In 16 cases the CNS hemorrhage was so extensive that it was considered to be the main cause of death. There was no significant statistical difference concerning sex (P = 0.217), age (P = 0.296), underlying disease (P= 0.352), preparatory regimens (P = 0.07), immunoprophylaxis (P = 0.914), chronic and acute graft-versus-host disease (P = 0.107 and P = 0.631, respectively) and survival (P = 0.701) when comparing patients with or without ICH. However, the number of cases in which the CNS was defined as the main cause of death was higher among patients with ICH than in patients without ICH (n = 16 vs 15) (P = 0.011). We conclude that ICH is common and has a significant mortality rate following BMT.

Cytomegalovirus pneumonia after bone marrow transplantation: high resolution CT findings.

Cytomegalovirus (CMV) pneumonia is one of the most common pulmonary complications after bone marrow transplantation (BMT). We describe the high resolution CT (HRCT) findings of 13 patients with CMV pneumonia diagnosed after allogenic BMT. The study included 13 consecutive patients who developed CMV pneumonia after BMT and who had HRCT of the chest performed within 24 h of the onset of symptoms. HRCT scans were reviewed by two radiologists who assessed pattern and distribution of findings. There were nine male and four female patients, ranging from 9 years to 56 years of age (mean age 33 years). BMT was performed for treatment of chronic myelogenous leukaemia (54%), severe aplastic anaemia (23%), acute myelogenous leukaemia (15%) and Fanconi's anaemia (8%). The time elapsed until diagnosis ranged from +18 days to +405 days (median of 54 days, mean +81.6 days). The predominant patterns of abnormality on HRCT scans were ground-glass opacities (69%), small centrilobular nodules (69%) and air-space opacities (54%). The abnormalities were distributed in the central and peripheral zones of the lungs in six cases, only in the periphery in four cases, and only in the central zone in three cases. In all cases the lung lesions were bilateral, and asymmetry was observed in seven cases. The authors conclude that the most common HRCT findings in patients with CMV pneumonia after BMT consist of bilateral asymmetric ground-glass, air-space opacities and small centrilobular nodules.

Pulmonary alveolar microlithiasis presenting with crazy-paving pattern on high resolution CT.

Pulmonary alveolar microlithiasis (PAM) is an uncommon chronic disease characterized by calcifications within the alveoli and a paucity of symptoms in contrast to the imaging findings. We present a 59-year-old woman with a 4-year history of shortness of breath on exertion. Lung auscultation revealed random wheezes and fine and coarse crackles. Pulmonary function tests showed a restrictive pattern. The chest radiograph demonstrated a bilateral symmetric micronodular pattern. High resolution CT scan revealed diffuse ground-glass attenuation with superimposed septal thickening ("crazy-paving" pattern). The patient underwent a lung biopsy, which confirmed the diagnosis of PAM. Our case demonstrates that PAM needs to be considerate in the differential diagnosis of lung lesions that present with crazy-paving pattern on the high resolution CT.

Mammary epithelioid myofibroblastoma arising in bilateral gynecomastia: case report with immunohistochemical profile.

Myofibroblastoma of the breast is a rare benign neoplasm, which has rarely been reported in association with gynecomastia. We report a case of a 25-year-old male patient with an epithelioid myofibroblastoma arising in a context of bilateral gynecomastia. The lesion was composed of nests and cords of epithelioid cells, with round to oval nuclei, granular chromatin, and distinct nucleoli dispersed in a myxoid to collagenous stroma with marked vascular proliferation. Immunohistochemical profile showed diffuse positivity for vimentin and focal immunoreactivity for desmin, whereas cytokeratins (CAM5.2 and AE1/AE3), EMA, alpha smooth muscle actin, actin HHF35, CEA, S100, factor VIII, neuron-specific enolase, CD31, and CD34 were all negative. We emphasize that this diagnosis is difficult to establish, owing to the rarity of this variant and clinical presentation.

Pleomorphic xanthoastrocytoma: report of a case diagnosed by intraoperative cytopathological examination.

The authors present an unusual case of a 13-yr-old boy with a 3-mo history of seizures. A CT scan showed a contrast-enhancing mass located in the left temporal lobe. The patient underwent a stereotatic-guided craniotomy; intraoperative cytological diagnosis was performed by the smear technique, showing a pleomorphic xanthoastrocytoma. The tumor was totally resected. Definitive diagnosis was established by examination of paraffin-embedded material. Six months after the surgical intervention, the patient is doing well, with no radiological evidence of recurrence. The cytological differential diagnosis of giant cell lesions of the central nervous system is emphasized.

[Medulloblastomas: clinical, epidemiological and pathological findings in 28 cases]. / Meduloblastomas: achados clínicos, epidemiológicos e anátomo-patológicos de 28 casos.

We report the clinical, epidemiological and pathological findings of 28 patients with medulloblastoma: 22 were male; age ranged from 1 to 50 years, with a mean of 15 years. The most frequent symptoms and signs were headache (64%) and vomiting (64%). Only one patient showed a desmoplastic medulloblastoma variant, the others showed classical medulloblastomas. Regarding treatment, most patients were submitted to total resection (n=10) or partial tumorectomy (n=7). A low rate of tumoral recurrence was observed, occurring in 21% of the patients (n=6) after 4 years of follow-up. Chemotherapy seemed to contribute to a lower recurrence rate amongst our patients. Our findings are similar to those reported in literature, thus helping to understand the biological behavior of this type of tumor.

[Haemangioblastomas: clinical, epidemiological and pathological findings in 14 cases]. / Hemangioblastomas: achados clínicos, epidemiológicos e anatomopatológicos em 14 casos.

We report the clinical, epidemiological and pathological findings of 14 patients with haemangioblastoma. Sixty-four percent occurred in males, with ages ranging from 16 to 60 years, with an average of 34, 4 years. Most of the tumours were confined to the cerebellum (n=9). The most frequent symptoms were headache (n=7) and dizziness (n=7), with a mean duration of 70 days. Von Hippel-Lindau syndrome (vHL) was diagnosed in 3 patients. Eleven patients were submitted to total surgical removal and in 3 the tumour was partially resected. A relapse rate of 28% in 3 years of follow-up was found. The patients with vHL showed recurrence in 66% of the cases. These findings corroborate those in current medical literature, showing an increased morbidity of this tumor when associated with vHL.

[Meningiomas in pediatric patients: report of 2 cases]. / Meningiomas em pacientes pediátricos: relato de 2 casos.

Meningiomas correspond to 1% - 4% of primary intracranial tumors in pediatric group, with their incidence raising according to age. There is not gender prevalence, in spite of some authors describe a male tendency opposed to female one in adulthood. At present study we describe two cases of pediatric meningiomas reviewing clinical, radiological and histological aspects of these lesions. The authors review also treatment options and prognosis of childhood meningiomas. A two-year-old boy was admitted with seizures. Computerized tomography showed a right parietal lesion, which was totally resected. Histological features were compatible with meningioma. After 17 months the child is doing well, with no deficits or seizures. The second case is a 12-year-old girl, with a headache complain. During investigation, a CT revealed a right frontal lesion. She was operated under a right frontal craniotomy with total tumor resection. Nowadays she is asymptomatic, 20 months after surgery. Despite meningiomas in pediatric group are uncommon; they should be included in differential diagnosis list of expansive intracranial lesions of childhood.

[Uncommon presentation of central neurocytoma causing intraventricular hemorrhage: case report]. / Neurocitoma central com apresentação incomum por hemorragia intraventricular: relato de caso.

Central neurocytoma was first described by Hassoun et al. in 1982 as a well-differentiated tumor from neuronal origin. This tumor typically occurs in young adults, localized in the ventricular system. It usually presents as intracranial hypertension due to obstructive hydrocephalus. The differential diagnosis should be done with others intraventricular tumors as oligodendroglioma, subependymoma and choroidal plexus papilloma. There are few cases of central neurocytoma presented by intraventricular hemorrhage in the literature. We report a case of 35 year-old woman, who presented with obstructive hydrocephalus due to intraventricular hemorrhage within the tumor. MRI revealed a tumor localized in the right lateral ventricle. Histopathological and immunohystochemical analysis confirmed the diagnosis of central neurocytoma. We review options for the treatment of this entity as well reinforce the inclusion of central neurocytoma as a differential diagnosis for intraventricular hemorrhage.

[Cerebrovascular diseases in patients aged 15 to 40 years: neuropathological findings in 47 cases]. / Doenças cerebrovasculares em pacientes entre 15 e 40 anos: achados neuropatológicos em 47 casos.

Cerebrovascular diseases in patients between 15 and 40 years old are not a frequent subject in Latin-American literature, especially when focusing on neuropathology. We analyzed 47 brains from necropsies performed from 1987 to 1997 and selected on a basis of age and the presence of vascular pathology. From the 47 analyzed brains, 26 belonged to females (55.3%). When distributed among age groups, 12.8% (n=6) affected patients from 15 to 20 yo, 51,1% (n=24) from 21 to 30 yo, 36,2% (n=17) from 31 to 40 yo. The underlying diseases were: cardiac and haemathologic (19.2%), pregnancy complications (12.76%), infections, diseases of blood vessels and neurological (10.1% each) amongst others. The neuropathological abnormalities included cerebral and/or cerebellar herniation (16%), cerebral edema (13.8%), subarachnoid hemorrhage (10%), recent cerebral infarction (9%), intraparenchymatous hemorrhage (8.14%), hypoxic-ischemic encephalopathy (3%) and other events such as Sneddon syndrome and Lupus vasculitis. These findings express that the cerebrovascular phenomena in this age group are unique and closely related with the underlying disease.

[Neurocysticercosis: a clinical and pathological study of 27 necropsied cases]. / Neurocisticercose: estudo clínico e patológico de 27 casos de necrópsia.

Neurocysticercosis is the most frequent and widespread neuroparasitosis of the human being. The development of brain and leptomeningeal lesions, with subsequent symptoms, are mainly related with the immune status of the host, and to the number and evolutional phase of the parasites. We present the pathological findings in 27 necropsies of patients with neurocysticercosis, which accounted for 3.1% of the necropsies. 77% of the patients were male and the age ranged from 18 to 85 years. In 26% there was previous history of alcoholism. Clinicopathological study showed that 50% of the cases were classified as asymptomatic form, 11% epileptic form, 11% intraventricular form and 11% combined form. 33% of the patients presented seizures as a factor of aggravation of the clinical picture. There was a single cysticercus in 60% of the cases, the cellulosae form present in 82% and the racemous form in 7% of the cases; the remaining 11% had both forms present. In 30% of the patients the cause of death was directly related with the presence of the cysticercus in the central nervous system. Our findings confirm the high morbidity of this disease.

[Use of botulinum toxin in the treatment of laryngeal dystonia (spasmodic dysphonia): preliminary study of twelve patients]. / O uso da toxina botulínica no tratamento da distonia laríngea (disfonia espasmódica): estudo preliminar com doze pacientes.

Laryngeal dystonia (spasmodic dysphonia) is a movement disorder characterized by involuntary contractions of laryngeal muscles involved with vocalization. The introduction of botulinum toxin in the treatment of laryngeal dystonia had a major clinical impact due to the striking improvement of symptoms. We report the preliminary results of therapeutical use of botulinum toxin in the treatment of twelve patients with laryngeal dystonia. After an extensive clinical evaluation, the patients underwent a videostroboscopic exam for diagnostic confirmation. Botulinum toxin was injected in the cricothyreoid membrane, directed towards the thyreoaritenoid muscle, with the aid of eletromyography needles. Most of patients who underwent botulinum toxin injection had a significant improvement of their symptoms (83%), with effects lasting for four months in average and without important side effects.

Is there manual asymmetry in movement preparation?

Manual asymmetry in response preparation was investigated in simple and complex movements by using simple reaction-time tasks. The simple movement consisted of lifting the index finger, while in the complex one subjects reversed direction of movement to hit a switch after reaching for and grasping a tennis ball. Analysis showed that performance with either the right or the left hand was equivalent, with longer latencies for reacting on the complex task in comparison to the simple one. These findings indicate similar capabilities of the right and the left cerebral hemispheres to prepare the motor system for action independently of the spatial requirements of movement.

Neuromyelitis optica: a diffusional kurtosis imaging study.

BACKGROUND AND PURPOSE: Conventional MR imaging typically yields normal images of the brain or indicates lesions in areas of high aquaporin expression in patients with neuromyelitis optica. Diffusional kurtosis imaging was applied in patients with neuromyelitis optica to determine whether this technique could detect alterations in diffusion and diffusional kurtosis parameters in normal-appearing white matter and to explore the relationship between diffusional kurtosis imaging and DTI parameters. MATERIALS AND METHODS: Thirteen patients with neuromyelitis optica and 13 healthy controls underwent MR imaging of the brain with conventional and diffusional kurtosis imaging sequences. Tract-based spatial statistics and region-of-interest-based analyses were conducted to identify differences between patients with neuromyelitis optica and controls through conventional DTI and diffusional kurtosis imaging parameters. The parameters were correlated to determine the potential relationship between them. RESULTS: Compared with healthy controls, several diffusional kurtosis imaging and DTI parameters were altered in various fiber tracts of patients with neuromyelitis optica (P < .05). A significant decrease (P < .05) in radial kurtosis was observed in the corpus callosum and anterior corona radiata and left optic radiation. Differences (P < .1) in mean kurtosis were found in patients with neuromyelitis optica. We found a negative correlation between diffusional kurtosis imaging (radial kurtosis, axial kurtosis, mean kurtosis) and the corresponding DTI parameters (radial diffusivity, axial diffusivity, mean diffusivity). Positive correlations were found for radial kurtosis and mean kurtosis with fractional anisotropy. CONCLUSIONS: This study demonstrated differences in conventional diffusion and diffusional kurtosis parameters, especially radial kurtosis, in the normal-appearing white matter of patients with neuromyelitis optica compared with healthy controls. Larger studies of patients with neuromyelitis optica should be performed to assess the potential clinical impact of these findings.