Tectal Glioma

Tectal gliomas (click image for arrows) fall under the grouping of childhood brainstem gliomas. They are typically low grade astrocytomas which expand the tectal plate, thereby narrowing the aqueduct of Sylvius and causing hydrocephalus. As they are slow growing, shunting is often the only required intervention for long term survival.
Additional symptoms my include gaze palsies, due to compression of the medial longitudinal fasciculus leading to an upgaze palsy, diplopia or Parinaud syndrome.
Typically these tumours demonstrate expansion of the tectal plate, with no enhancement. On T2WI the lesion is either iso or hyperintense to the remainder of the brainstem.
Credit: Dr Frank Gaillard
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