Cavernoma with Venous Angioma

A pontine Cavernoma (Cavernous Malformation) with an associated venous angioma has very typical imaging findings on MR as in this case.

MRI Brain Axial T1 and FLAIR, Axial post contrast CT. 

A pontine intra axial focal lesion with typical "popcorn ball" appearance, T1 bright locules which corresponds to Meth Hb – a sub acute stage blood degradation product. Low signal intensity hemosiderin rim on T2. No perilesional edema. No mass effect or volume loss. Blooming on GRE due to paramagnetic effect of blood degradation products. 

An associated venous angioma may be seen as in this case seen as enhancing serpentine hyperdensity on contrast enhanced CT. 

A venous angioma, also referred to as a "developmental venous anomaly" (DVA), a variation of normal. Usually seen as a little cluster or may seen as single prominent vein. May be seen isolated or in association with cavernoma as in thise case. Angioma on their own don't tend to cause any trouble, except very few (reported) exceptions of bleed, so should generally be left alone. When associated with cavernous malformations (cavernomas) tend to be troublesome, usually present with seizures.

Related post :
Venous Angioma with bleed : Venous Angioma a rare cause of intracerebral bleed.
Cavernoma-cavernous-malformation
Venous-angioma