[MRI symptomatology of primary intraspinal cord gliomas]. / Sémiologie IRM des gliomes primitifs intra-médullaires.

MRI has now been recognized as the best technique for exploration of spinal tumours and, in particular, tumours within the spinal cord. Based on a retrospective study of 74 operated glial tumours, we are trying to define a specific semiology for intramedullary astrocytomas and ependymomas. Thirty-four cases were selected including 17 astrocytomas (7 low-grade, 10 high-grade) and 17 ependymomas (1 of which was grade III) for whom the pre-operative MRI examination was complete, with T1-weighted sequences without, then with gadolinium, and T2-weighted sequences. The examination was performed using a high-field and in most cases 1.5 Tesla machine. Analysis, correlated with operative data and pathology results, comprised on the one hand patients' distribution by age, sex and location of the tumour on the spinal cord, and on the other hand the MRI semiology concerning the sagittal and axial localization of the fleshy portion after gadolinium injection, the limits of the tumour, the homo- or heterogeneous character of its enhancement, the possible existence of stigmas of intra- or peritumoral chronic bleeding, and finally the presence or absence of associated cysts in the 34 exploitable cases. Some semiological differences were elicited between astrocytomas and ependymomas: the patient's age at the time of diagnosis was predominantly 0 to 20 for astrocytomas (astrocytomas 39%, ependymomas 4%), and the well-limited character of the fleshy portion of the tumour after gadolinium injection was found in 70% of ependymomas, 40% of high-grade astrocytomas and 14% of low-grade astrocytomas. The homogeneity of contrast enhancement in ependymomas has been classically defined, but it did not show in our series. Finally, it seems that high-grade astrocytomas are characterized by the rare presence of hemosiderin deposits (high-grade 20%, low-grade 57%, ependymomas 58%) and by the absence or reduced extension of overlying and underlying cysts.

[Brain and spinal cord cavernoma. Value of MRI and review of the literature. Apropos of a case]. / Cavernomatose encéphalo-médullaire. Intérêt de l'IRM et revue de la littérature. A propos d'une observation.

MRI has transformed the diagnosis of cavernous hemangioma, a hamartoma that is most often located in the central nervous system. The appearance of this lesion is fairly characteristic with MRI. This technique has allowed distinguishing multiple forms. Encephalic sites are most frequent, with rare medullary sites, and double brain and cord locations are exceptional. Many cases of single or multiple brain involvement have now been reported. Series of medullary involvement are much less frequent and include few cases. Double sites in the brain and cord are exceptional. The authors present a case of cavernous hemangiomas of the central nervous system with multiple encephalic sites associated with a single medullary site confirmed by surgery.

[Secondary malignant tumors of the vestibulocochlear and facial nerves]. / Tumeurs malignes secondaires des nerfs vestibulo-cochléaire et facial.

INTRODUCTION: Neuromas and meningiomas represent by far the most frequent tumors of the cerebellopontine cistern (respectively over 80% and over 10%). Secondary malignant tumors are exceptional. METHOD: Presentation of four cases of malignant tumors of the cerebellopontine cistern, either revealing or complicating a primary tumor: a bronchial cancer, a cancer of the kidney, a medulloblastoma and a lymphoma. Patients were studied in T2- and T1-weighted high-field MRI sequences before and after gadolinium injection. RESULTS: The four tumors were enhanced by gadolinium and shown to invade the internal auditory canal, including one bilateral involvement. In most cases, the tumors were slightly heterogeneous and had irregular margins. CONCLUSION: These observations suggest that other diagnoses than acoustic neuroma should be taken into account.

Gadolinium-enhanced MRI in central nervous system Behçet's disease.

Two cases of central nervous system Behçet's disease, studied by gadolinium-enhanced MRI, are presented. In one patient, whose clinical picture was dominated by a brain syndrome, the gadolinium enhancement resolved with clinical improvement, although the hyperintense areas in the mesencephalon on T2-weighted images persisted. In the second, who had a pseudobulbar palsy and a mild right hemiparesis, there were many abnormal areas, but an enhancing focus in the posterior limb of the left internal capsule was probably the lesion responsible for the hemiparesis.

[MRI of malformative syringomyelia. Descriptive and developmental aspect]. / IRM des syringomyélies malformatives. Aspect descriptif et évolutif.

132 cases of malformative syringomyelia have been studied at the C.I.E.R.M. (Interdepartmental Magnetic Resonance Center) of Bicêtre Hospital. The authors describe their technique for the exploration on the cord in case of suspected intramedullary cavitation, and emphasize the morphological and evolutive aspects of these abnormalities, whether they have been operated or not.

[Ante- and posthypophyseal insufficiency with infundibulum abnormalities]. / Insuffisance anté-et post-hypophysaire avec anomalies de la tige pituitaire.

The hypopituitarism and the diabetes insipidus are often idiopathic. A retrospective study of 6 cases of diabetes insipidus and 8 cases of partial or total idiopathic antehypophyseal insufficiency has shown the value of MRI to demonstrate anomalies of the infundibulum or hypothalamic-hypophysis "stages". MRI allows to bring together some cases of idiopathic hypopituitarism in a new entity which is the hypopituitarism due to a newborn section of the infundibulum.

Anterior and posterior hypopituitarism with pituitary stalk abnormalities.

Hypopituitarism and diabetes insipidus are often idiopathic conditions. A retrospective study of 6 cases of diabetes insipidus and 8 cases of partial or global idiopathic anterior hypopituitarism has shown that MRI is of considerable value to detect abnormalities of the pituitary stalk or hypothalamo-pituitary "relay". On the basis of MRI findings, some cases of idiopathic hypopituitarism can now be grouped together in a new entity which may be called hypopituitarism due to neonatal transection of the pituitary stalk.

[Comparative study of Hexabrix and Lipiodol UF in sialography]. / Etude comparative de l'Hexabrix et du Lipiodol UF en sialographie.

Many new lipid- and water-soluble contrast media can be used in sialography, the three main criteria of choice being the cost, the quality of filling, particularly of the parenchyma, and its evacuation and clinical tolerance. Duroliopaque possesses very similar physicochemical properties to those of Lipiodol UF, but a sufficiently satisfactory filling of the parenchyma is not obtained. Comparison of Lipiodol UF and Hexabrix in parotid and submaxillary contrast imaging showed good clinical tolerance for both products, but improved parenchymatous filling with Lipiodol UF. However, the more effective glandular evacuation with Hexabrix makes this the product most suitable at the present time for morphologic exploration of salivary glands.