Central nervous system lymphoma: magnetic resonance imaging features at presentation.

OBJECTIVE: This paper aimed at studying presentations of the central nervous system (CNS) lymphoma using structural images obtained by magnetic resonance imaging (MRI). METHODS: The MRI features at presentation of 15 patients diagnosed with CNS lymphoma in a university hospital, between January 1999 and March 2011, were analyzed by frequency and cross tabulation. RESULTS: All patients had supratentorial lesions; and four had infra- and supratentorial lesions. The signal intensity on T1 and T2 weighted images was predominantly hypo- or isointense. In the T2 weighted images, single lesions were associated with a hypointense signal component. Six patients presented necrosis, all of them showed perilesional abnormal white matter, nine had meningeal involvement, and five had subependymal spread. Subependymal spread and meningeal involvement tended to occur in younger patients. CONCLUSION: Presentations of lymphoma are very pleomorphic, but some of them should point to this diagnostic possibility.

Central nervous system lymphoma: magnetic resonance imaging features at presentation / Linfoma do sistema nervoso central: características da imagem de ressonância magnética à apresentação

OBJECTIVE: This paper aimed at studying presentations of the central nervous system (CNS) lymphoma using structural images obtained by magnetic resonance imaging (MRI). METHODS: The MRI features at presentation of 15 patients diagnosed with CNS lymphoma in a university hospital, between January 1999 and March 2011, were analyzed by frequency and cross tabulation. RESULTS: All patients had supratentorial lesions; and four had infra- and supratentorial lesions. The signal intensity on T1 and T2 weighted images was predominantly hypo- or isointense. In the T2 weighted images, single lesions were associated with a hypointense signal component. Six patients presented necrosis, all of them showed perilesional abnormal white matter, nine had meningeal involvement, and five had subependymal spread. Subependymal spread and meningeal involvement tended to occur in younger patients. CONCLUSION: Presentations of lymphoma are very pleomorphic, but some of them should point to this diagnostic possibility.

OBJETIVO: Este trabalho teve como objetivo estudar as apresentações do linfoma do sistema nervoso central (SNC) por meio de imagens estruturais, obtidas por ressonância magnética (RM). MÉTODOS: Foram analisadas as características das imagens por RM, à apresentação, de 15 pacientes diagnosticados com linfoma do SNC em um hospital universitário, entre janeiro de 1999 e março de 2011, pela frequência e por tabulação cruzada. RESULTADOS: Todos os pacientes apresentaram lesões supratentoriais; em quatro (27 por cento) havia lesões infra e supratentoriais. A intensidade do sinal em T1 e T2 foi predominantemente hipo ou isointensa. Lesões únicas foram associadas ao componente de sinal hipointenso nas imagens ponderadas em T2. Seis pacientes apresentaram necrose. Foram encontrados: alteração de sinal da substância branca perilesional em todos os pacientes, acometimento meníngeo em nove e disseminação subependimária em cinco. Disseminação subependimária e acometimento meníngeo tenderam a ocorrer nos pacientes mais jovens. CONCLUSÃO: As apresentações do linfoma no SNC são pleomórficas, mas algumas delas podem apontar para essa possibilidade diagnóstica.

Compartment syndrome after Bothrops jararaca snakebite: monitoring, treatment, and outcome.

OBJECTIVE: To report the outcome of a patient who developed compartment syndrome after Bothrops jararaca snakebite. CASE REPORT: A 39-year-old male was admitted 5 h after being bitten on the lower right leg. Physical examination revealed tense swelling, ecchymosis, hypoesthesia, and intense local pain that worsened after passive stretching, limited right foot dorsiflexion, and gingival bleeding. The case was classified as moderate/severe and eight vials of bothropic antivenom (AV) were infused 1 h postadmission. The main laboratory findings upon admission were incoagulable blood (incoagulable PT, aPTT, and INR), thrombocytopenia, serum creatine kinase (CK) of 580 U/L (reference value < 170 U/L), and a serum venom level of 33.7 ng/mL (ELISA; cutoff = 2.3 ng/mL). High anterior compartment pressure (60 mmHg) was identified 8 h post bite, with progressively lower pressures after AV administration and limb elevation (36 mmHg; 19 h post bite). However, moderate pain and limited foot dorsiflexion persisted. In addition, there was a progressive increase in serum CK (6,729 U/L; 45 h post bite), as well as marked edema and hemorrhage of the anterior compartment detected by magnetic resonance imaging (MRI) at 48 h post bite. A fasciotomy done after a further increase in intracompartmental pressure (66 mmHg, 57 h post bite) revealed hemorrhage/necrosis of the anterior tibial muscle that subsequently required partial resection. The patient developed a local infection (day 15 post bite) and a permanent fibular palsy. CONCLUSION: Compartment syndrome is an unusual but severe complication of snakebites. MRI, in conjunction with subfascial pressure measurements, may be useful in the diagnosis of compartment syndrome after snakebites.

Brainstem involvement in Sjögren's syndrome-related sensory neuronopathy.

BACKGROUND AND PURPOSE: Sensory neuronopathies (SN) are peripheral nervous system disorders associated with degeneration of dorsal root ganglion neurons. Magnetic resonance imaging (MRI) studies have shown abnormalities limited to T2-weighted high signal intensity in the posterior columns. METHODS AND RESULTS: A 65-year-old woman with Sjögren syndrome had slowly progressive unsteadiness of gait and limb paresthesias. A blink reflex examination suggested a paramedian brainstem lesion, confirmed by MRI. CONCLUSIONS: Sjögren's syndrome-related SN may be associated with a more diffuse immune-mediated aggression, involving also the brainstem, and leading to some of the blink reflex abnormalities observed in nonparaneoplastic SN.

MRI findings in the diagnosis and monitoring of Rasmussen's encephalitis.

Rasmussen's encephalitis is a devastating syndrome of multifocal brain dysfunction and focal seizures. Magnetic resonance (MR) findings, associated with clinical data and electroencephalogram (EEG), may indicate the diagnosis and could be an indicative of prognosis. We studied 5 patients with Rasmussen's encephalitis, assessing clinical history and MR images. All patients had refractory focal seizures with a predominant motor component associated with hemispheric atrophy, that was proportional to severity of disease and neurological deficits in these patients. Gray and white matter abnormal signal on T2 MR images were found in patients who had hemiparesis. It was not related to the duration of the disease but to aggressiveness. MR proton spectroscopy in severe disease showed lactate and choline increase and decreased NAA, reflecting neuronal and axonal loss, gliosis and elevated membrane turnover and recent - crisis (not controlled). MR studies, in addition to help in diagnosis, may be useful for monitoring metabolic changes and progression of disease in Rasmussen's encephalitis.