A 60-year-old woman who developed intermittent diplopia underwent MRI scan revealing a tentorial meningioma as well as aneurysms of the posterior communication artery, right vertebral artery, and peripheral superior cerebellar artery. The tentorial meningioma tumor was located in the posterior aspect of the cerebellopontine angle and causing compression of the brainstem along the course of the 4th cranial nerve, and the complex, partially thrombosed dissecting aneurysm of the SCA was situated just proximal to the entry of the 4th nerve into the free edge of the tentorium. Angiography revealed a partially thrombosed wide-necked aneurysm not amenable to endovascular intervention. Microsurgical clipping and simultaneous tumor removal were recommended.\nA combined subtemporal, presigmoidal approach was performed. A wide bone removal of the middle cranial fossa was necessary to reach the tentorial incisura allowing exposure of the tumor. Due to the associated brainstem compression from the tumor, the meningioma was debulked first, and then the aneurysm was addressed. Interestingly, on reaching the SCA there was obvious hemosiderin staining of the arachnoid surrounding the aneurysm dome, indicating a previous rupture. During microsurgical dissection, it was confirmed that this aneurysm was thick-walled and partially thrombosed [Figure and ]. The aneurysm was reconstructed with a single clip placed well up on the aneurysm dome to avoid compromise of the parent artery. Intra-operative angiogram demonstrated complete obliteration of the aneurysm with normal flow through the SCA and distal branches. Post-operatively, apart from transient hyponatremia and hyperglycemia, the patient did well without complication.
A 55-year-old woman visited our ED with a complaint of vertigo and sudden-onset headache. A diffusion-weighted MRI revealed a high-signal intensity lesion in the right cerebellar hemisphere [], leading to the diagnosis of CI. Although depiction of the right PICA was poor, a pathologic process involving the PICA remained unclear []. CTA performed the next day revealed a pearl-string lesion at the orifice of the right PICA [], establishing the diagnosis of a right PICA dissection. The patient recovered uneventfully with conservative management, including administration of aspirin. A repeated CTA obtained a month after admission showed improvement in the stenosis of the PICA distal to the dissection [].