Meningeal Dissemination and Drop Metastasis From Glioma Presenting With Non-Epileptic Myoclonus and Minipolymyoclonus

Neurohospitalist. 2024 Oct 28:19418744241297396. doi: 10.1177/19418744241297396. Online ahead of print.

Abstract

We describe the case of a 36-year-old woman with a past medical history of low grade right frontal lobe glioma and focal epilepsy presenting with subacute, progressive, multifocal myoclonus and neck and back pain. Unlike her typical seizures, the myoclonus exhibited a distinct semiology, involving both positive and negative muscle jerks affecting multiple limb muscles while sparing the face. In addition, neurological examination revealed low-amplitude, arrhythmic movements of the hands and fingers, resembling minipolymyoclonus. There were no other neurological exam findings, including mental status changes, extrapyramidal signs or signs of myelopathy. Brain and spine MRI indicated leptomeningeal and spinal "drop" enhancing lesions, suggesting likely malignant evolution of the glioma. EEG ruled out a cortical origin of the myoclonus. Pharmacological trials with benzodiazepines and other antiepileptic medications were ineffective. The patient's myoclonus was most likely spinal segmental in origin from meningeal spread of glioma. The spinal roots or anterior horns of the spinal cord may have represented a focus of hyperexcitability responsible for generating minipolymyoclonus. Our case expands the etiological spectrum of non-epileptic myoclonus and minipolymyoclonus to encompass meningeal carcinomatosis and drop metastases from glioma. These cases may occur even without overt signs of myelopathy. Recognizing such presentations holds significance due to the poor prognosis associated with meningeal spread of glioma and the limited response of non-epileptic myoclonus to symptomatic treatments.

Keywords: high grade glioma; leptomeningeal; polyminimyoclonus; spinal segmental myoclonus.