Is This Truly A "Leave-Me-Alone" Lesion? An Unusual Case of Multiple Ring-shaped Lateral Ventricular Nodules

Ring-shaped lateral ventricular nodules (RSLVNs) are commonly considered as benign asymptomatic lesions, which are sporadically detected as incidental findings on routine brain magnetic resonance imaging scans. Despite their not irrelevant frequency, the exact biological nature of these lesions remains largely unknown due to the lack of histopathologic studies. Here we present the clinical, neuroradiologic, and histopathologic findings of an unusual case of symptomatic multiple RSLVNs.

A 44-year-old otherwise healthy man presented with a recent history of headache and retching. Neuroradiologic imaging revealed the presence of multiple RSLVNs, the largest of which, located in the cella media of the right lateral ventricle, exerted a mild to moderate mass effect on adjacent brain parenchyma. This latter nodule was successfully removed, with complete resolution of the symptoms. Histopathology revealed glial differentiation, and the specimen was diagnosed as subependymoma.

This report provides novel evidence characterizing RSLVNs as possible variants of subependymoma with a peculiar imaging appearance, also suggesting that, like subependymomas, they may occasionally grow large enough to cause mass effect-related symptoms, thus requiring neurosurgical intervention.