May Be Caused by

 Common

Basilar artery aneurysm

Basilar artery ectasia

Cerebellar neoplasm

Chordoma

Choroid plexus tumor

Epidermoid

Meningioma

Pontine glioma

Vertebral artery aneurysm

Vertebral artery ectasia

 Uncommon

Arachnoid cyst

Arteriovenous malformation

Glomus jugulare tumor

Hemangioma

Langerhans cell histiocytosis

Lipoma

Metastasis

Paraganglioma

Parasitic cyst

Rhabdomyosarcoma

Schwannoma