Meckel's Cave and Leptomeningeal Tumor

  What is Meckel's Cave? And what is a leptomeningeal tumor?
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Dear Laura:
Meckel's cave is an anatomical region in the base of the skull located in a area called the middle cranial fossa. It is a shallow hollowing in the apex of what is called the petrous bone, and it houses the trigeminal or Gasserian ganglion, which is a part of the 5th cranial nerve, which deals with facial sensation and muscles of chewing. There is one Meckel's cave on either side. The Meckel's cave can be the site of tumor involvement.
Common tumors include meningiomas, epidermoid tumors, and metastases.
A leptomeningeal tumor is one that is connected with the leptomeninges, or the arachnoid and pia mater (the inner two and thinner of the three layers of the meninges). A meningioma, although closely related to the leptomeninges, is more commonly described as being a dural-based tumor. Metastatic carcinomas, melanomas, lymphomas, and primary brain tumors (such as medulloblastomas, ependymomas) are more characteristically leptomeningeal.
I hope this helps.