Background: Subependymomas are rare, slow-growing WHO grade I ependymal tumors
comprising 0.2–0.7% of intracranial neoplasms, most often in the fourth or lateral ventricles.
They usually present in mid-life with male predominance and are frequently incidental MRI
findings—small, T2-hyperintense, circumscribed nodules with minimal enhancement and no
hydrocephalus. Symptoms, when present, arise from mass effect or CSF obstruction (e.g.,
headache, gait imbalance, cranial neuropathies). Migratory sensory phenomena are highly
atypical. Given their indolent nature and excellent prognosis after resection, observation is often
appropriate for asymptomatic, non-obstructive lesions.
Case: A 22-year-old woman experienced three discrete, self-limited sensory events over four months. The first involved bilateral hand numbness resolving in 16 hours. On 9 May, she had two episodes: the first began with left V2 numbness spreading to lips, tongue, and both arms, with transient right facial weakness; the second started with right forearm numbness, progressing to recurrent paresthesias in V2–V3 and tongue, again with brief right facial paresis. Each episode lasted about one hour, followed by mild headache. Neurologic exam and labs were normal. MRI revealed a 7 × 7 × 11 mm T2-hyperintense, mildly enhancing lesion in the floor of the fourth ventricle without hydrocephalus or mass effect, consistent with subependymoma. Multidisciplinary consensus recommended surveillance. At six months, MRI was unchanged and no further episodes occurred.
Conclusion: In young adults, episodic migratory paresthesias often prompt evaluation for demyelinating disease, yet may uncover incidental tumors. Small, non-obstructive fourth- ventricle subependymomas can be safely managed with interval imaging.
Case: A 22-year-old woman experienced three discrete, self-limited sensory events over four months. The first involved bilateral hand numbness resolving in 16 hours. On 9 May, she had two episodes: the first began with left V2 numbness spreading to lips, tongue, and both arms, with transient right facial weakness; the second started with right forearm numbness, progressing to recurrent paresthesias in V2–V3 and tongue, again with brief right facial paresis. Each episode lasted about one hour, followed by mild headache. Neurologic exam and labs were normal. MRI revealed a 7 × 7 × 11 mm T2-hyperintense, mildly enhancing lesion in the floor of the fourth ventricle without hydrocephalus or mass effect, consistent with subependymoma. Multidisciplinary consensus recommended surveillance. At six months, MRI was unchanged and no further episodes occurred.
Conclusion: In young adults, episodic migratory paresthesias often prompt evaluation for demyelinating disease, yet may uncover incidental tumors. Small, non-obstructive fourth- ventricle subependymomas can be safely managed with interval imaging.