Roberto Gomes Nogueira

White matter spectroscopy in neuromyelitis optica: a case control study.

BackgroundNaa/Cr ratio in normal appearing white matter (NAWM) of patients with multiple sclerosis (MS) is altered beyond plaques, suggesting early axonal loss, and correlates to clinical disability. Brain lesions not typical of MS have been described in Neuromyelitis optica (NMO), and correspond to brain aquaporin-4 channel sites, but the evaluation of Naa/Cr ratio in NAWM of patients with NMO and its association to the presence of brain lesions and clinical disability have not been described.ObjectivesTo evaluate the Naa/Cr of normal appearing white matter (NAWM) in 16 patients with NMO compared to healthy controls.MethodsWe performed brain magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) of 16 patients with NMO and compared to age matched healthy controls.ResultsNAWM Naa/Cr did not show statistical difference among patients and controls, neither between patients that had normal brain MRI and atypical brain lesions.ConclusionNAWM was found to have a normal Naa/Cr in patients with NMO, reinforcing the concept that the white matter is not primarily affected in this disease.

Diffusion tensor imaging of the cervical spinal cord of patients with Neuromyelitis Optica.

BACKGROUND Previous studies have demonstrated a correlation between Expanded Disability Status Scale (EDSS) and Diffusion Tensor Imaging (DTI) metrics, but the conclusions were based on evaluations of the entire cervical spinal cord. OBJECTIVES The purpose of this study was to quantify the FA and MD values in the spinal cord of NMO patients, separating the lesion sites from the preserved sites, which has not been previously preformed. In addition, we attempted to identify a correlation with EDSS. METHODS DTI was performed in 11 NMO patients and 11 healthy individuals using a 1.5-T MRI scanner. We measured the FA and MD at ROIs positioned along the cervical spinal cord. The mean values of FA and MD at lesion, preserved and spinal cord sites were compared with those of a control group. We tested the correlations between the mean FA and MD with EDSS. RESULTS FA in NMO patients was significantly reduced in lesion sites (0.44 vs. 0.55, p=0.0046), preserved sites (0.46 vs. 0.55, p=0.0015), and all sites (0.45 vs 0.55, p=0.0013) while MD increased only in lesion sites (1.03×10(-3)mm(2)/s vs. 0.90×10(-3)mm(2)/s, p=0.009). The FA demonstrated the best correlation with EDSS (r=-0.7603, p=0.0086), particularly at lesion sites. CONCLUSIONS The results reinforce the importance of the FA index and confirm the hypothesis that NMO is a diffuse disease.

BASAL ENCEPHALOCELE ASSOCIATED WITH MORNING GLORY SYNDROME : Case report

The basal encephaloceles refer to rare entities and they correspond to herniation of brain tissue through defects of skull along the cribiform plate or the sphenoid bone. A rare morning glory syndrome, with characteristic retinal defect has been reported in association with basal encephaloceles. Hypophysis hormonal deficiencies may occur. We accounted for a pituitary dwarfism with delayed diagnosed transsphenoidal encephalocele associated with morning glory syndrome, showing the alterations found in retinography, computed tomography and magnetic resonance imaging.

Temporal pole signal abnormality on MR imaging in temporal lobe epilepsy with hippocampal sclerosis: a fluid-attenuated inversion-recovery study

OBJECTIVE To determine the frequency and regional involvement of temporal pole signal abnormality (TPA) in patients with hippocampal sclerosis (HS) using fluid-attenuated inversion-recovery (FLAIR) MR imaging, and to correlate this feature with history. METHOD Coronal FLAIR images of the temporal pole were assessed in 120 patients with HS and in 30 normal subjects, to evaluate gray-white matter demarcation. RESULTS Ninety (75%) of 120 patients had associated TPA. The HS side made difference regarding the presence of TPA, with a left side prevalence (p=0.04, chi2 test). The anteromedial zone of temporal pole was affected in 27 (30%) out of 90 patients. In 63 (70%) patients the lateral zone were also affected. Patients with TPA were younger at seizure onset (p=0.018), but without association with duration of epilepsy. CONCLUSION Our FLAIR study show temporal pole signal abnormality in 3/4 of patients with HS, mainly seen on the anteromedial region, with a larger prevalence when the left hippocampus was involved.

Magnetic resonance findings in amyotrophic lateral sclerosis using a spin echo magnetization transfer sequence: preliminary report

We present the magnetic resonance (MR) findings of five patients with amyotrophic lateral sclerosis (ALS) using a spin-echo sequence with an additional magnetization transfer (MT) pulse on T1-weighted images (T1 SE/MT). These findings were absent in the control group and consisted of hyperintensity of the corticospinal tract. Moreover we discuss the principles and the use of this fast but simple MR technique in the diagnosis of ALS.

Absence of mutations in Pax6 gene in three cases of Morning Glory syndrome associated with isolated growth hormone deficiency

Morning glory syndrome (MGS) is a congenital optic disc dysplasia often associated with craniofacial anomalies, especially basal encephalocele and hypopituitarism. Clinical signs are varied and often occult. The PAX6 gene is involved in ocular morphogenesis and is expressed in numerous ocular tissues during development especially in the developing central nervous system. The aim of the present study is to evaluate PAX6 in MGS associated with isolated growth hormone deficiency. Three pre-pubertal males (A, B and C) with MGS and short stature due to growth hormone deficiency, treated with recombinant human growth hormone with limited response, were reported. Two of them had basal encephalocele. Coding and non-coding sequences corresponding of PAX6 different transcripts were analyzed by direct sequencing. Nucleotide variations causing putative aminoacid change were not observed. Patient A presented the new IVS2+9G>A transition, whereas patients A and C were heterozygous for known single nucleotide polymorphisms (SNP) within the intron 4. In addition, two SNP heterozygoses were observed for patient C in both intron 9 and 13. Sequencing also revealed several nucleotide variations in patient B. Two heterozygoses for known polymorphisms were identified along with a novel C>A nucleotide change in intron 4. This patient also presented a low number on the TG repeat in intron 9 and a new IVS11+33A>T transversion. Gene regulation and transcription of PAX6 are complex processes; there are two major protein isoforms, PAX6(-5a) and PAX6(+5a), and nine transcripts described. Furthermore, extra transcription regulatory elements have been postulated within PAX6 introns. Considering that neither population distributions on PAX6 polymorphism nor their linkeages with diseases have been reported, a functional effect due to alterations described here cannot be discarded.

Doppler transcraniano convencional em voluntários assintomáticos: variabilidade e valores de referência para parâmetros de fluxo sanguíneo

OBJECTIVE: To establish reference values for measures of blood flow velocities and impedance indexes in healthy individuals through conventional transcranial Doppler (TCD) and to observe their variations in relation to the age and sex. METHOD: 88 asymptomatic volunteers were examined without antecedents of cardiac, peripheral or cerebrovascular diseases. The TCD were accomplished by the same examiner. The middle, anterior and posterior cerebral arteries were studied through the temporal acoustic window and the vertebral and basilar arteries through the suboccipital acoustic window. The values of mean velocity (MV), peak-systolic velocity (PSV), final diastolic velocity (FDV), resistance index (RI) and pulsatility index (PI) of each examined arterial segment were filed. RESULTS: The reference limits found by us were similar to the described by other authors for all of the studied parameters. There was tendency of the flow velocities decrease and of the impedance indexes increase with moving forward of the age. The values of velocities in the women were superior to the found in men. CONCLUSION: TCD was shown useful in the evaluation of hemodynamic cerebral for our population. Our results are similar to the other studies, so much in the reference values as in relationship with the age and the sex.

Gliomas múltiplos: casos ilustrativos de quatro formas de apresentação

Multiple gliomas are uncommon and may be classified according to: a) the time of presentation in early (at diagnosis) or late (during treatment); b) the characteristics of computed tomography or magnetic resonance imaging (CT/MRI) in multifocal (with evidence of spread) and multicentric (without evidence of spread). From 212 patients with histopathologic diagnosis of glioma evaluated from March/90 to September/99, 15 (7%) had multiple lesions. We describe 4 patients: early multicentric, late multicentric, early multifocal and late multifocal, with emphasis on characteristics of CT/MRI and possible differential diagnosis. The differential diagnosis of multiple lesions in the central nervous system includes mainly infectious/inflammatory diseases and metastasis, however multiple gliomas should always be considered, even in patients with known systemic cancer, as described by others. Considering that CT/MRI features are not definite, the diagnosis should always be confirmed by histopathologic examination.Multiple gliomas are uncommon and may be classified according to: a) the time of presentation in early (at diagnosis) or late (during treatment); b) the characteristics of computed tomography or magnetic resonance imaging (CT/MRI) in multifocal (with evidence of spread) and multicentric (without evidence of spread). From 212 patients with histopathologic diagnosis of glioma evaluated from March/90 to September/99, 15 (7%) had multiple lesions. We describe 4 patients: early multicentric, late multicentric, early multifocal and late multifocal, with emphasis on characteristics of CT/MRI and possible differential diagnosis. The differential diagnosis of multiple lesions in the central nervous system includes mainly infectious/inflammatory diseases and metastasis, however multiple gliomas should always be considered, even in patients with known systemic cancer, as described by others. Considering that CT/MRI features are not definite, the diagnosis should always be confirmed by histopathologic examination.

Actinomicose do sistema nervoso central: uma rara complicação da actinomicose cervicofacial

Central nervous system actinomycosis is a rare but treatable chronic suppurative bacterial infection. The case of a young immunocompetent male with actinomycosis of the CNS is presented. The abscess originated from a primary cervico-facial infection and was located in the left parasellar region. After excision of the mass, that showed Actinomyces colonies, the patient was treated with intravenous Penicillin for 42 days followed by oral administration of the drug for 30 days. After surgery the patient was left with mild sequelae that had improved by the last follow-up, 7 months later. A new CT scan at that time revealed no residual disease or recurrence. The early diagnosis of cerebral actinomycosis relies essentially on a clinical suspicion. Hence it is imperative to be aware of the natural history of this infection and its various modes of presentation.

Associaçäo de malformaçäo vascular e gliomas: estudo de quatro casos

We reviewed the clinical presentation, imaging and histopathologic findings in 4 patients with the diagnosis of arteriovenous malformation associated with glioma that were operated on from 1991 to 2000 in our institution. Four patients (2 males; age between 15 and 52 years) presented with progressive headache with clinical evidence of intracranial hypertension (in 3) and partial seizures (in 1). CT scan showed a brain tumor without any detectable pathologic vessels. Histologic examination revealed astrocytic tumors associated with arteriovenous malformation. No patient presented the vascular component intermixed with the tumor. The arteriovenous-glioma association is rare and must be identified by a clear demarcation between the malformation and the tumor.Entre os pacientes operados no Hospital Sao Paulo e acompanhados pelo setor de neuro-oncologia no periodo de 1991 a 2000, avaliamos a apresentacao clinica, aspectos de imagem e caracteristicas histopatologicas de 4 pacientes (2 homens; idade entre 15 e 52 anos) cujo diagnostico histologico foi malformacao vascular associada a glioma. O quadro inicial foi cefaleia progressiva com caracteristicas de hipertensao intracraniana (em 3) e crises parciais motoras (em 1). O diagnostico tomografico inicial foi processo expansivo, sem que houvesse suspeita de malformacao vascular pelo aspecto da imagem em nenhum caso. O exame histologico mostrou neoplasias de linhagem astrocitica associadas a malformacoes vasculares. Em nenhum paciente o componente vascular esteve localizado na intimidade da neoplasia. A associacao de malformacao vascular e gliomas e rara e deve ser caracterizada por nitida separacao entre a malformacao e a neoplasia, independente da vascularizacao propria do tumor.