History: A 44-year-old man presents with a history of chronic migraines and fatigue. The patient was found to have low testosterone levels on further workup.
正确答案：Multinodular and vacuolating neuronal tumors (MVNT)
多结节和空泡（或囊泡）神经元肿瘤
Pathophysiology
- Multinodular and vacuolating neuronal tumors are indolent, subcortical tumors with a small and “bubbly” appearance.
- Most frequently identified in the temporal lobe, although this relationship is likely due to the location being more likely to result in seizures and subsequent imaging than a true representation of tumor predilection for the temporal lobe.
- Macroscopically, they will appear as small, gray, well-formed, coalescent nodules.
- Microscopically, mature neurons will be seen embedded within a fibrillary background, with large cytoplasmic vacuoles.
Epidemiology
- True epidemiological information is currently unknown, as MVNTs have only recently been described.
- Reported cases are commonly seen in young to middle-aged adults who usually present with adult-onset seizures.
Clinical presentation
- Many MVNTs are likely asymptomatic and found incidentally on imaging performed for other reasons.
- When symptomatic, adult-onset seizures and seizure equivalents (e.g., episodic confusion) are the principal clinical manifestations. Focal, complex partial, grand mal seizures, and status epilepticus have all been described in association with MVNTs.
Imaging features
- CT: CT demonstrates nonenhancing low-attenuation lesions in the subcortical white matter.
- MRI:
- T1: Appear hypointense to adjacent gray and white matter.
- T2: Appear as hyperintense “bubbles” when compared with gray and white matter. Signal almost as high as cerebral spinal fluid.
- FLAIR: Does not suppress.
- T1 with contrast: Show faint focal enhancement, or most commonly no enhancement.
Treatment
- MVNTs are indolent, benign tumors that can be followed with imaging alone if not causing symptoms.
- If symptomatic (seizures), surgical resection is often performed with resulting control of seizures for a majority of patients, and no tumor regrowth reported to date.