What is the differential for infundibular thickening and enhancement?
tumours (e.g. germinoma; CNS lymphoma; pituicytoma; metastases), infection (e.g. tuberculosis, bacterial meningitis), cellular infiltrates (e.g. Langerhans cell histiocytosis; neurosarcoidosis; lymphocytic hypophysitis).
Of these which can give you such widespread enhancement elsewhere?
Metastatic disease, infection and cellular infiltrates such as neurosarcoidosis.
What would be a reasonable approach to working this patient up?
A lumbar puncture with biochemistry, cytology, culture and cell count, as well as a CT of the chest, abdomen and pelvis, looking for a primary or other features helpful in narrowing the differential diagnosis.
Abnormal contrast enhancement of the:
- hypophyseal stalk, tuber cinereum and midline portion of hypothalamus as well as the subependymal portions of the third ventricle (blue arrows)
- nodular enhancement also seen along veins running along the posterior aspect of the third ventricle (red arrows)
- faint parenchymal enhancement particularly in the right parietal lobe (yellow arrows)
- soft tissue within the third ventricle at the level of the foramina of Monro (green arrow)