Membrana de Liliequist: avaliação radiológica e suas implicações clínicas e terapêuticas / Liliequist membrane: radiological evaluation, clinical and therapeutic implications

A membrana de Liliequist, de maneira simplista e sucinta, pode ser entendida como uma projeção formada pela aracnoide que se estende do dorso da sela turca aos corpos mamilares. Apesar de se tratar de uma estrutura anatômica bem conhecida pelos neurocirurgiões, muitos radiologistas não a conhecem ou não valorizam seu estudo. A avaliação por imagem desta membrana é factível e pode ser interessante para o melhor planejamento pré-operatório, avaliação pós-operatória de terceiro-ventriculostomias e entendimento dos cistos aracnoides suprasselares e hemorragias perimesencefálicas. Ilustramos neste artigo os aspectos anatômicos da membrana, sobretudo do ponto de vista de imagem, além de suas possíveis implicações clinicocirúrgicas.

In a simplistic and succinct way, Liliequist membrane may be understood as a projection formed by an arachnoid membrane extending from the dorsum sellae to the mammillary bodies. In spite of being well known to neurosurgeons, many radiologists neither know this anatomical structure nor give importance to its study. The imaging evaluation of this membrane is feasible and may be interesting for a better preoperative planning; postoperative evaluation of third ventriculostomies; and understanding of suprasellar arachnoid cysts and perimesencephalic hemorrhage. The present article illustrates the anatomy of the membrane, with emphasis on imaging findings, besides describing its possible clinical and surgical implications.

Estudo através da ressonância magnética de 67 casos de glioblastoma multiforme e a ocorrência de metástases / Magnetic resonance imaging in 67 cases of glioblastoma multiforme and occurrence of metastases

OBJETIVO: Demonstrar as características de imagem do glioblastoma multiforme, tumor primário mais comum do sistema nervoso central, com ênfase em suas localizações, ocorrência de metástases e relação com o grau de necrose demonstrado por ressonância magnética (RM). MÉTODO: Foram analizados retrospectivamente 67 casos de ressonância magnética de pacientes com diagnóstico histológico de glioblastoma multiforme, retirados do arquivo didático da MED IMAGEM. Todos os exames foram realizados em aparelhos GE de 1,5 T. (GE- Medical Systems), no período compreendido entre janeiro de 1995 e maio de 2003. RESULTADOS: Nos 67 casos estudados, a idade dos pacientes variou entre 4 e 86 anos, com idade média de 60 anos. Houve predominância no sexo masculino, com 39 casos (58 por cento). A localização frontal foi preponderante (47 por cento) seguida de 18 por cento na região temporal e 16 por cento na região parietal. Em 19 por cento se localizou em outros sítios. O aparecimento de metástases ocorreu em 15 casos. CONCLUSAO: Concordante com a literatura o glioblastoma multiforme predomina nos lobos frontais e acomete preferencialmente pacientes com idade acima de 50 anos. O aparecimento de metástases em nossos casos ocorreu em 22 por cento.

Analysis of parahippocampal gyrus in 115 patients with hippocampal sclerosis

PURPOSE: Analysis of the parahippocampal gyrus (PHG) involvement in 115 patients with hippocampal sclerosis (HS) by MR imaging. The simultaneous occurrence of ipsilateral fornix (F) and mamillary body (MB) volume loss was checked also. These findings were correlated with the side of hippocampal involvement, the sex, patient s age, and the symptoms onset. METHOD: The MR images of 115 patients with HS were studied retrospectively. All the examinations were performed on 1.5 T units (SIGNA, GE, Milwaukee, WI) and included high resolution coronal T2-weighted images (3 mm thickness, 0.6 mm gap). RESULTS: The patient's age ranged between 3.5 and 80 years (mean 34.1); 62 (53.9 percent) were female and 53 (46.1 percent) were male. There were HS on the left side in 53 (46.0 percent), on the right side in 51 (44.3 percent), and bilateral in 11 (9.7 percent). In 43 (37.3 percent) cases there were ipsilateral PHG volume loss and signal hyper intensity on T2-weighted imaging. In 29 (25.2 percent) cases there were ipsilateral fornix volume loss and in 10 (34.5 percent) of this there were also ipsilateral MB changes. In abnormal PHG, 23 (53.4 percent) were on the left side, 17 (39.5 percent) were on the right side, and 3 (7.1 percent) were bilateral. There were fornix changes in 15 (34.8 percent) cases and MB volume loss in 5 (11.6 percent) cases. Pertinent clinical data were obtained in only 18 (41.8 percent) of the PHG lesion cases and 11 (61.1 percent) of these patients had epileptic attacks for more than 20 years before the examination. CONCLUSION: PHG involvement must be investigated in patients with HS and we suggest that the term mesial temporal sclerosis should be used only if there are also changes at this anatomical site

MR imaging for evaluation of lesions of the cranial vault: a pictorial essay

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. RESULTS: The results were: dermoid cysts [4 cases (5 percent)], epidermoid cysts [2 cases (2.5 percent)], cephalocele [14 cases (17.5 percent)], sinus pericranii [3 cases (3.7 percent)], leptomeningeal cysts [4 cases (5 percent)], Langerhans cell histiocytosis [10 cases (12.5 percent)], lipoma [4 cases (5 percent)], fibrous dysplasia [13 cases (16.2 percent)], osteoma [8 cases (10 percent)], hemangioma [1 case (1.2 percent)], meningioma [3 cases (3.7 percent)], chondrosarcoma [5 cases (6.2 percent)], hemangiosarcoma [1 case (1.2 percent)], multiple myeloma [3 cases (3.7 percent)], sarcomatous transformation of Paget disease [1 case (1.3 percent)], and metastasis [5 cases (6.2 percent)]. CONCLUSION: MRI identifies bone marrow abnormalities and invasion of adjacent tissues at an early stage. Therefore, it is an essential method when it commes to properly evaluating calvarial lesions

Ununsual manifestations of neurocysticercosis in MR imaging: analysis of 172 cases

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 percent); intraventricular 27 cases (15.69 percent); subarachnoid 20 cases (11.63 percent); spinal 6 cases (3.49 percent); orbital 1 case (0.58 percent); reactivated lesion 1 case (0.58 percent); association of intraventricular and intraparenchymatous 12 cases (6.98 percent); association of subarachnoid and intraparenchymatous 6 cases (3.49 percent); association of subarachnoid and intraventricular, 4 cases (2.32 percent). 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

Serviço Integrado de Neurogeriatria. Ambulatório da Memória - Análise dos resultados iniciais / Neurogeriatric Integrated Service. Memory Clinic - description of the initial results

Demência é o declínio da capacidade intelectual e adequação social em grau suficiente para afetar as atividades de vida diária. A demência pode ter várias etiologias, sendo algumas reversíveis. O Ambulatório da Memória do Serviço Integrado de Neurogeriatria da Real e Benemérita Sociedade Portuguesa de Beneficência - Hospital São Joaquim - propõe um modelo de atendimento multidisciplinar para o diagnóstico e tratamento das síndromes demenciais, com os seguintes resultados preliminares: dos 104 pacientes, 10 (9,6 por cento) não apresentavam deterioração intelectual. Dos 94 demais, 27 (28,7 por cento) tinham afecções potencialmentereversíveis: 18 casos de doença psiquiátrica; dois de doenças metabólicas; três de intoxicações exógenas e 4 casos de hidrocefalia. Foram 67 casos (71,2 por cento) de perda cognitiva causada por lesão estrutural, dos quais 42 pacientes (62,5 por cento) tinham doença de Alzheimer, que, atualmente possui tratamento específico. A proposta de uma equipe multidisciplinar, bem estruturada, pode beneficiar estes pacientes e seus familiares