Dural cavernous angioma of the posterior sagittal sinus: case report.

Background: Extraaxial cavernous hemangiomas (cavernomas) are very rare lesions, and less than 20 descriptions of these lesions outside the middle fossa have been reported. In this report, we describe a dural cavernous angioma involving the posterior sagittal sinus and discuss the clinical, radiological, operative, and histological features of this very uncommon lesion.

Methods: A 31-year-old right-handed male presented with headache and decreasing visual acuity. Severe bilateral papilledema was found on fundoscopic examination. Neurological examination demonstrated a minor right temporal field cut. Brain magnetic resonance imaging with contrast demonstrated a 2.5 x 2.5 cm hyperintense enhancing mass in the midline, which was contiguous with the posterior margin of the falx cerebri. The patient underwent a bilateral occipital craniotomy centered on the lesion. The histological features were consistent with cavernous angioma.

Conclusions: This report demonstrates that although extra axial cavernomas are quite rare, they must be included in the differential diagnosis of enhancing lesions along the posterior sagittal sinus. The operative removal of these lesions can be quite treacherous and usually requires a careful reapproximation of the patent sinus after lesion excision.