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-Purpose:A variety of diseases affect the calvaria. They may be identified clinically as palpable masses or incidentally in radiologic examinations. There are many diagnostic possibilities, including congenital, neoplastic, inflammatory and traumatic lesions. The purpose of this study is to illustrate the main calvarial lesions through MR imaging, their signal intensity and extension to neighboring sites. Method: A retrospective analysis of 81 cases, from November 1996 to July 2001, was conducted. The examinations were performed on a 1.5 T equipment and each one of the cases was pathologically proven. Conclusão: A RM detecta precocemente as alterações que envolvem a medula óssea, bem como demonstra acuradamente o envolvimento dos tecidos adjacentes. Este método é fundamental na avaliação detalhada das lesões da calota craniana.

-Purpose: The typical manifestations of neurocysticercosis are described widely in the literature. The purpose of this study is to demonstrate the uncommon presentations of different forms of neurocysticercosis in MR imaging. Method: A retrospective analysis of 172 cases of neurocysticercosis in MR studies was carried out over a period of 13 years. One hundred and four males and 68 females with a mean age of 32 ± 3.7 years were studied. The studies were performed on 1.5 T GE MR units and T1 was used before and after gadolinium injection, T2 and gradient-echo (T2*) sequences. Results: The authors divided the unusual manifestations of neurocysticercosis into: intraventricular, subarachnoid, spinal, orbital, intraparenchymatous, and reactivation of previously calcified lesions. The results obtained were: intraparenchymatous 95 cases (55.23%); intraventricular 27 cases (15.69%); subarachnoid 20 cases (11.63%); spinal 6 cases (3.49%); orbital 1 case (0.58%); reactivated lesion 1 case (0.58%); association of intraventricular and intraparenchymatous 12 cases (6.98%); association of subarachnoid and intraparenchymatous 6 cases (3.49%); association of subarachnoid and intraventricular, 4 cases (2.32%). Conclusion: MR imaging is a sensitive and specific method in the analysis of different forms of unusual manifestations of neurocysticercosis, which should appear in the differential diagnosis of parenchymal, ventricular, spinal, cisternal, and orbital lesions.KEY WORDS: cysticercosis, parasites, MRI, subarachnoid space. Manifestações incomuns na ressonância magnética da neurocisticercose: análise de 172 casosRESUMO -Objetivo: as manifestações típicas da neurocisticercose já são bem conhecidas. O papel deste estudo foi demonstrar os aspectos incomuns da neurocisticercose na ressonância magnética. Método: foram analisados 172 casos de ressonância magnética de neurocisticercose na Med Imagem num período de 13 (treze) anos em aparelhos GE de 1.5T Signa (Horizon, LX e CVI). Dos casos analisados, foram diversas as formas de apresentação, incluindo intraventricular, intraespinhal, cisternal, orbital, formas atípicas parenquimatosas (simulando tumores), forma miliar e evolução não usual (reativação). Conclusão: A ressonância magnética é método sensível e específico na avaliação das numerosas formas de apresentação atípica da neurocisticercose, as quais devem constar no diagnóstico diferencial de lesões intraventriculares, cisternais, orbitárias e parenquimatosas. PALAVRAS-CHAVE: cisticercose, parasitas, ressonância magnética, espaço subaracnóide.

This study was designed to evaluate with magnetization transfer imaging (MTI) and conventional magnetic resonance (MR) imaging the manifestation of diffuse axonal injury (DAI) in an animal model of injury via nonimpact coronal plane rotational acceleration. A second objective was to investigate the diagnostic use of quantitative MTR imaging based on statistical parameters in a single subject, as opposed to grouped analysis. Seven mini‐swine were subjected to brain trauma known to produce isolated DAI and to MR imaging at two time points. Following sacrifice, the brains were harvested for histopathologic examination. Magnetization transfer ratio (MTR) maps were generated for double‐blinded comparison of regions with abnormal MTR values and regions with documented DAI. Positive and negative predictive values for MTR detection of DAI were 67 and 56%, respectively, and in acute studies alone, 89 and 61%. Gains in sensitivity over conventional imaging for detection of DAI were demonstrated. Magn Reson Med 41:727–733, 1999. © 1999 Wiley‐Liss, Inc.

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