Presentation
Headache.
Patient Data
There are a few bilateral small subependymal nodules isodense to the grey matter in the wall of the lateral ventricles, protruding into the ventricular bodies; the largest is in the left lateral ventricular wall and measures about 7 mm in length.
Mega cisterna magna (normal variant).
Multiple bilateral well-defined small nodules along both lateral ventricular walls, the largest measuring 9 x 7 mm, which appear isointense to grey matter on all sequences, without diffusion restriction, blooming artifact or postcontrast enhancement.
Case Discussion
Features suggestive of ring-shaped lateral ventricular nodules (RSLVN), “leave me alone” lesions.
RSLVN are an incidental finding in patients who undergo neuroimaging, mainly for headache.
The cause of the RSLVN is not well understood, and multiple theories have been advanced for the pathophysiology of these lesions, including neuroglial cyst, inflammatory or reactive formation of ependyma, astrocytic gliosis reaction near subependymal veins, redetachment of the fused portion of coarctation of the frontal horn or a variant of subependymoma 1.
The differential diagnosis includes subependymal heterotopia in patients with epilepsy and subependymal nodules in patients with tuberous sclerosis 1.