Dumbbell-shaped middle cranial fossa meningioma with interdural cavernous sinus extension: report of two cases with complete removal.

BACKGROUND: Surgery for meningiomas involving the cavernous sinus remains controversial. Interdural cavernous sinus is called the lateral dural wall in the cavernous sinus, which is composed of two layers, the outer dural layer and the inner membranous layer. We encountered two cases of dumbbell-shaped middle cranial fossa meningioma with interdural cavernous sinus extension, which were successfully removed by surgical means.

CASE DESCRIPTION: A 57-year-old woman presented with headache and decreased visual acuity. Neurological assessment was normal. Computed tomography and magnetic resonance imaging showed the presence of a dumbbell-shaped, smooth-contoured, well-enhanced mass in the right mesial temporal area. The lateral wall of the cavernous sinus was exposed via frontotemporal craniotomy and the tumor originating in the lateral wall was totally removed. A 41-year-old man presented with seizure attacks and drowsy mental status. Magnetic resonance imaging showed the presence of a multilobulated, well-enhanced mass in the left parasellar area. The tumor was totally resected via a transsylvian temporopolar approach. The mass originated from tentorial edge and extended into the cavernous sinus by dural penetration.

CONCLUSION: Middle cranial fossa meningioma with interdural cavernous sinus extension can be removed more easily than other tumors with intracavernous sinus extension and, consequently, can be safely resected without any resulting cranial nerve deficit.