Glomus tympanicum paraganglioma - imaging findings

Brief description.
From Diagnostic Imaging: Head and Neck by H. Ric, Harnsberger.

1. Glomus tympanicum paraganglioma I maging findings

2. most common middle ear tumor f rom tympanic branch of IXth cranial nerve otoscopy – vascular mass behind intact tympanic membrane

3. mass with flat base on cochlear promontory if large can occupy most of or entire middle ear

4. best imaging tool high resolution CT with bone algorithm only and no contrast MRI + contrast if large tumor or glomus jugulotympanicum

5. CT – look for bone destruction middle ear floor intact, if osteolysis glomus jugulotympanicum ossicle destruction may reach tympanic membrane o tomastoid fluid due to attic block jugular invasion erosion of carotid canal

6. MRI if glomus jugulotympanicum suspected on CT salt and pepper due to flow voids usually not seen because mass too small avid enhancement + early washout MR venography for jugular bulb invasion

7. e nhancing middle ear mass – DDX glomus tympanicum paraganglioma angiographically positive pedunculated facial nerve schwannoma angiographically negative

8. most common middle ear mass behind intact TM congenital cholesteatoma however this does not enhance in child or young adult

9. a sk referring clinician color and location of retrotympanic mass red , anteroinferior – GTP blue , posteroinferior – dehiscent jugular bulb red , crossing from posterior to anterior – aberrant ICA white, inferior – congenital cholesteatoma white, superior – facial nerve schwannoma