Meckel's Cave Tumors: Relation to the Meninges and Minimally Invasive Approaches for Surgery Anatomic and Clinical Studies

BACKGROUND Literature on tumors originating from Meckel's cave (MC) and their surgical treatment are scarce. OBJECTIVE We present 37 cases of tumors originating from MC, the largest single-institution series reported thus far, and discuss the ideal surgical methods for each tumor type in relation to the normal and pathological anatomy of MC. METHODS We studied 37 cases of surgery for tumors in MC (26 schwannomas, 7 meningiomas, 2 epidermoids, 1 hemangiopericytoma, and 1 dermoid) performed at our institution between 1986 and 2008. We excluded cases of large tumors of unknown origin, especially meningiomas. Surgery for tumors in MC was performed via 2 approaches: anterolateral interdural access (Dolenc's) approach and posterior access via the anterior petrosal approach (APA). RESULTS The Dolenc approach was useful for parasellar tumors, especially schwannomas, because it resulted in minimal damage to the temporal lobe and adjacent cranial nerves. The APA was useful for dumbbell-shaped tumors extending into the posterior fossa. Tumors of nonmeningeal origin (schwannomas, epidermoids, and dermoids) were safely resected, with no postoperative complications except facial hypesthesia. However, incidence of postsurgical paresthesia and abducens palsy were higher in meningioma and hemangiopericytoma, because of invasion into the Gasserian ganglion, the cavernous sinus (CS), or Dorello's canal. CONCLUSION An understanding of meningeal structure around MC enhances the radicality of tumor resection and helps minimize damage to adjacent structures. However, meningiomas and hemangiopericytomas occurring in MC, which can infiltrate into the CS, should be treated by both surgery and radiosurgery to minimize postoperative complications.