The cerebellopontine angle (CPA) is a relatively frequent site of intracranial masses, many of which are relatively specific for the region.
It is worth dividing cerebellopontine angle masses into three groups, based on imaging characteristics.
- enhancing masses
- masses with high T1 signal on MRI
- masses with CSF intensity / density
- acoustic schwannoma : ≈ 80 % of CPA masses (commonest by far)
- meningioma : ≈ 10 % of CPA masses (2nd commonest)
- trigeminal schwannoma
- facial nerve schwannoma
High T1 signal mass
- haemorrhagic acoustic schwannoma
- neurenteric cyst : usually prepontine, but fluid may be proteinaceous and high on T1
- thrombosed berry aneurysm : often will have calcified rim, and haemosiderin staining.
- white epidermoid : rare, and will restrict on DWI
- cerebellopontine angle lipoma : usually has the facial nerve and vestibulocochlear nerve coursing through it. Will saturate on fat suppressed sequences.
- ruptured intracranial dermoid : often multiple droplets, and original midline lesion can be often seen.
CSF density mass
Many other masses can present at or around the cerebellopontine angle. They include:
- primary melanocytic neoplasm
- cholesterol granuloma
- petrous apicitis
- endolymphatic sac tumour
- pituitary adenoma
- brainstem glioma
- choroid plexus papilloma
- DNET (dysembroblastic neuroepithelial tumour)
- ganglioglioma (rare 3)
- 1. Bonneville F, Sarrazin JL, Marsot-dupuch K et-al. Unusual lesions of the cerebellopontine angle: a segmental approach. Radiographics. 21 (2): 419-38. Radiographics (full text) - Pubmed citation
- 2. Fink JR. Imaging of cerebellopontine angle masses: self-assessment module. AJR Am J Roentgenol. 2010;195 (3): S15-21. doi:10.2214/AJR.09.7191 - Pubmed citation
- 3. Kwon JW, Kim IO, Cheon JE et-al. Cerebellopontine angle ganglioglioma: MR findings. AJNR Am J Neuroradiol. 2001;22 (7): 1377-9. AJNR Am J Neuroradiol (full text) - Pubmed citation
Synonyms & Alternative Spellings
|Synonyms or Alternative Spelling||Include in Listings?|
|CP angle mass||✗|
|Lesions of the cerebellopontine angle||✗|
|Cerebellopontine angle lesions||✗|