Mri

MRI is the study of choice to identify both intra-and extramedullary spinal cord neoplasms [4]. Extramedullary lesions are readily identified as such and their relation to the cord, attachment to dura and displacement of the cord are visualized.

MRI scans should be performed before and after intravenous administration of contrast agents (gadolinium diethylene-triamine-pentacetic acid), with T1-weighted images in multiple planes [19]. These images demonstrate the solid tumor component. T2-weighted images optimally show the cerebrospinal fluid and tumor-associated cysts. While MRI does not allow for a certain histologic diagnosis pre-operatively, the more common tumors have typical patterns of imaging appearance.

Ependymomas usually enhance brightly and homogeneously (Fig. 29.5), frequently have rostral and caudal cysts and, not uncommonly, a hemosiderin "cap" at their poles. On axial view, they are usually seen in the center of the cord. Astrocytomas (Fig. 29.3) and gangli-ogliomas (Fig. 29.4), on the other hand, enhance less frequently and, if enhancement is seen, it is more often heterogeneous. On axial images, these neoplasms are more frequently found to be eccentric in the cord. They may cause asymmetric enlargement of the cord. Hemangioblastomas (Fig. 29.8) characteristically show bright enhancement of a tumor nodule and associated cysts, often with significant cord edema adjacent to it. Meningiomas (Fig. 29.2) and nerve sheath tumors (Fig. 29.1) may have similar appearance on MRI and they commonly enhance brightly. Schwannomas sometimes show large cysts, while menin-giomas often can be identified by a broad dural attachment.

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The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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