Female, 62 years old, abnormal finding at the obex on a recent prior cervical spine MRI, further evaluation is requested. A 4 mm mildly T1 and T2 hyperintense nodule is evident within the medulla at the level of the obex. The lesion does not appear to follow CSF signal characteristics, and there is no correlating susceptibility artifact to suggest blood product. Furthermore it does not cause any significant structural deformation of the medulla.Elsewhere, scattered small periventricular T2 hyperintense lesions are seen, a nonspecific finding. No evidence of parenchymal edema or mass effect is seen. No intracranial hemorrhage or abnormal extra-axial collection is detected. The ventricular system is normal in size and morphology. No Chiari malformation is seen.
A 4 mm nodule is evident at the level of the obex within the medulla correlating to the abnormal finding on a recent prior cervical spine MRI. Based on the signal characteristics, this lesion may be solid or cystic containing proteinaceous but not necessarily hemorrhagic contents. The differential diagnosis would include a developmental cystic lesion such as a neuroglial cyst, ependymal cyst, or dermoid/epidermoid. Although less likely, a low grade neoplasm such as a subependymoma could be considered. A follow-up examination in 6-12 months is suggested.