Paulo Roberto Valle Bahia

Diffusion tensor MRI evaluation of the corona radiata, cingulate gyri, and corpus callosum in HIV patients

To evaluate the white matter integrity of the corona radiata, cingulate gyri, and corpus callosum in patients with human immunodeficiency virus (HIV) infection through diffusion tensor imaging (DTI).

Diffusion tensor MR imaging of white matter integrity in HIV-positive patients with planning deficit

IntroductionThe aim of this study was to evaluate whether normal controls and human immunodeficiency virus (HIV) patients with and without planning deficits differ on white matter integrity.MethodsA total of 34 HIV-positive patients with planning deficits were compared with 13 HIV-positive patients without planning deficits and 19 gender-, age-, and education-matched control subjects. Diffusion tensor imaging (DTI) was performed along 30 noncolinear directions in a 1.5-T scanner. For tract-based spatial statistics analysis, a white matter skeleton was created, and a permutation-based inference with 5000 permutations with a threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The median, radial, and axial diffusivities were also projected onto the mean FA skeleton.ResultsCompared with controls, HIV-positive patients with planning deficits had decreased FA in bilateral anterior thalamic radiations, bilateral inferior fronto-occiptal fasciculi, genu and splenium of the corpus callosum, bilateral superior longitudinal fascicule, and bilateral uncinate fasciculi. Compared to HIV-positive patients without planning deficits, patients with planning deficits had decreased FA in bilateral anterior thalamic radiations, bilateral inferior fronto-occiptal fasciculi, genu of the corpus callosum, bilateral superior longitudinal fascicule, and right uncinate fascicule.ConclusionDTI can detect extensive white matter abnormalities in the normal-appearing white matter of HIV-positive patients with planning deficits compared with controls and HIV-positive patients without planning deficits.

Longitudinal assessment of subcortical gray matter volume, cortical thickness, and white matter integrity in HIV-positive patients

To longitudinally evaluate the cortical thickness and deep gray matter structures volume, measured from T1 three‐dimensional (3D) Gradient echo‐weighted imaging, and white matter integrity, assessed from diffusion tensor imaging (DTI) of HIV‐positive patients.

Pyogenic and tuberculous discitis: magnetic resonance imaging findings for differential diagnosis

Spondylodiscitis represents 2%–4% of all bone infections cases. The correct diagnosis and appropriate treatment can prevent complications such as vertebral collapse and spinal cord compression, avoiding surgical procedures. The diagnosis is based on characteristic clinical and radiographic findings and confirmed by blood culture and biopsy of the disc or the vertebra. The present study was developed with Clementino Fraga Filho University Hospital patients with histopathologically and microbiologically confirmed diagnosis of spondylodiscitis, submitted to magnetic resonance imaging of the affected regions. In most cases, pyogenic spondylodiscitis affects the lumbar spine. The following findings are suggestive of the diagnosis: segmental involvement; ill-defined abscesses; early intervertebral disc involvement; homogeneous vertebral bodies and intervertebral discs involvement. Tuberculous spondylodiscitis affects preferentially the thoracic spine. Most suggestive signs include: presence of well-defined and thin-walled abscess; multisegmental, subligamentous involvement; heterogeneous involvement of vertebral bodies; and relative sparing of intervertebral discs. The present pictorial essay is aimed at showing the main magnetic resonance imaging findings of pyogenic and tuberculous discitis.

Brain MRI abnormalities in Brazilian patients with neuromyelitis optica.

Brain abnormalities in neuromyelitis optica (NMO) have been reported previously, but the pathophysiological mechanism and clinical relevance of these abnormalities are poorly understood. We assessed the prevalence and patterns of brain MRI abnormalities in a Brazilian cohort of patients with NMO. Conventional brain MRI and medical records from 24 Brazilian patients with NMO were retrospectively evaluated. Brain MRI were classified into four subgroups: normal, non-specific lesions, multiple sclerosis (MS)-like lesions, and typical lesions. Brain lesions were detected in 19 patients (79.2%). Fourteen patients (58.3%) had non-specific lesions, three (12.5%) had MS-like lesions, and two (8.3%) had typical lesions. Differences between these subgroups with respect to the Expanded Disability Status Scale (EDSS) scores (p=0.86) were not significant. This study demonstrates a high prevalence of brain abnormalities in Brazilian patients with NMO; however, we did not find a significant relationship between these abnormalities and EDSS scores.

Regional Cerebral Gray Matter Volume in HIV‐Positive Patients with Executive Function Deficits

To evaluate whether human immunodeficiency virus (HIV)‐positive patients with and without executive functions deficits and healthy control subjects differ on cortical thickness and subcortical brain structures volume in vivo.

Síndrome de Parry-Romberg: achados nas sequências avançadas de ressonância magnética - relato de caso

Parry-Romberg syndrome is a rare disease characterized by progressive hemifacial atrophy associated with other systemic changes, including neurological symptoms. Currently, there are few studies exploring the utilization of advanced magnetic resonance sequences in the investigation of this disease. The authors report the case of a 45-year-old patient and describe the findings at structural magnetic resonance imaging and at advanced sequences, correlating them with pathophysiological data.Parry-Romberg syndrome is a rare disease characterized by progressive hemifacial atrophy associated with other systemic changes, including neurological symptoms. Currently, there are few studies exploring the utilization of advanced magnetic resonance sequences in the investigation of this disease. The authors report the case of a 45-year-old patient and describe the findings at structural magnetic resonance imaging and at advanced sequences, correlating them with pathophysiological data.

Digitalização de filmes radiográficos com costura de imagens

OBJECTIVE: To propose a reproducible, user friendly and low cost method for digitization of radiographic films of all the standard sizes, focusing efforts on chest X-ray films. MATERIALS AND METHODS: The focus on low cost have dictated the use of an A4 scanner with transparency adapter, as well as an optimized image stitching software that takes advantage of the scanner geometry and constant capture area, besides the knowledge of the standard X-ray film sizes. RESULTS: The end result of the proposed method is a high resolution image with good contrast and no perceptible stitching artifacts. CONCLUSION: The proposed digitization method with an A4 scanner allows reproducibility, excellent image quality and high degree of certainty in the identification of lesions.

Neurofibromatose plexiforme retroperitoneal e pélvica: aspectos na tomografia computadorizada e ressonância magnética - relato de caso e revisão da literatura

The authors report a case of neurofibromatosis type I, characterized by multiple plexiform neurofibromas in the retroperitoneum and pelvis. Computed tomography showed markedly hypodense lesions involving mainly the psoas and the paravertebral regions, findings which could mimic other diseases such as abscesses and lymphadenopathy. Magnetic resonance imaging was useful to better evaluate the extension and internal structure of the neurofibromas.

Síndrome do granuloma letal da linha média: um dilema diagnóstico

The rare lethal midline granuloma syndrome is difficult to diagnose because of the wide array of related diseases and lack of knowledge by the majority of physicians. In the present report, the authors describe the case of a patient with this disease, caused by squamous cell carcinoma, drawing attention to differential diagnoses and to clinical and radiological findings that may be useful to define the diagnosis.