MRI diagnosis of primary tumors in Molkick cave

Objective: To explore the MRI characteristics of primary tumors in Meckel cave (MC), and to evaluate the diagnostic value of the changes of MC and adjacent structures. Methods: 14 pathologically confirmed primary tumors in Meckel cave were studied. Pre-contrast MRI scan was performed in 4 cases, post-contrast MRI scan in 2 cases, both pre- and post-contrast MRI scan in 8 cases. Results: (1) Schwannoma was the most common tumor, and followed by meningeoma, fibroneuroma, and cholesteatoma. (2) The meningeoma and cholesteatoma had characteristic signal in MRI, some Schwannoma and fibroneuroma had similar MRI demonstrations. (3) The change of MC included cave enlargement, bulging dural walls, trigeminal cistern narrowing or obliteration, loss of fibers-background contrast. (4) The changes of adjacent structures included compression of temporal lobe, pons, basilar artery, cerebellar hemisphere, and the forth ventricle, cavernous sinus narrowing, and petrous pyramid hone absorption. Conclusions: The signals of tumors were helpful to establish the diagnosis, and can be used to estimate the tumor pathological components, the changes of MC and adjacent structure can be used in localizing the tumors. (authors)