Background:Only a limited number of dissecting aneurysms of the peripheral cerebellar arteries have been previously described, and very few of these cases involve the superior cerebellar artery (SCA). Due to the rarity of these lesions, there is little consensus regarding prognosis and management. We describe our experience with two cases of complex peripheral SCA dissecting aneurysms and review the existing literature on this fascinating entity.Case Description:Two patients, both with SCA dissecting aneurysms not amenable to endovascular treatment underwent microsurgical clipping, one with the associated removal of a tentorial meningioma. In each procedure a combined subtemporal, presigmoidal approach was performed. Surgical clips were utilized to reconstruct the aneurysms, and both patients were discharged without complication. Surgical management of complex distal SCA fusiform aneurysm is challenging and options include wrap/clip reconstruction, proximal occlusion, trapping, and distal outflow occlusion. When possible, preservation of the parent artery is preferred to mitigate the risk of brainstem infarction. If proximal occlusion or trapping are employed, we have advocated for the use of combined distal revascularization techniques to prevent permanent ischemic damage of the brainstem and cerebellar hemisphere.Conclusions:Peripherally dissecting aneurysm of the SCA is an uncommon entity. Management of these lesions is best handled by an experienced neuro-endovascular team combined with a neurovascular surgeon skilled in skull base approaches.

Background:To describe the use of a short segment cortical intracranial–intracranial (IC–IC) bypass for the treatment of a distal middle cerebral artery (MCA) aneurysm.Case Description:A 54-year-old woman presented with a loss of consciousness followed by multiple seizures and was found to have a partially thrombosed distal MCA aneurysm. This possibly mycotic aneurysm was treated by creating a short segment jump graft between a normal cortical artery and a nearby cortical branch arising from the aneurysmal M3 arterial segment. The bypass allowed for subsequent occlusion of the aneurysmal vessel without ischemic consequence. At surgery, the anterior division of the superficial temporal artery (STA) was exposed and dissected. Intraoperative angiography was utilized to localize a cortical artery arising from the involved segment as well as a nearby cortical artery arising from a distinct, uninvolved MCA branch. A segment of the STA was harvested, and then 10-0 suture was utilized to anastomose this short segment, to both the involved and normal cortical arteries. This created a short jump graft allowing for subsequent sacrifice of the diseased artery. Following surgery, the patient immediately underwent coil embolization of the aneurysm back into the parent artery resulting in local vascular sacrifice. The remainder of the patient's hospital course was uneventful. She was discharged home in good condition.Conclusions:We suggest that cortical IC–IC bypass followed by endovascular arterial sacrifice as performed in our case represents a simple and safe option for treating unclippable distal MCA aneurysms including mycotic lesions.

We describe our experience with the use of a single dose of rFVIIa administered perioperatively in an attempt to decrease the rate of intraoperative aneurysm rupture in patients undergoing microsurgical aneurysm clipping. There were no significant immediate or long-term adverse effects attributable to the use of rFVIIa in this group, and we encountered no intraoperative ruptures in this relatively small series.

Objective:We describe a rare case of a patient with subarachnoid hemorrhage (SAH) due to a ventral dissecting mid-basilar aneurysm that was treated surgically. One week after surgery, the patient experienced sudden deterioration due to a new SAH caused by the development of a new aneurysm of the basilar trunk distinct from the previously clipped aneurysm.Case Description:A 54-year-old woman with acute subarachnoid hemorrhage was found to have a small, broad-based aneurysm arising from the ventral aspect of the mid-basilar artery. This complicated lesion was treated with a microsurgical clipping via a translabyrinthine pre-sigmoidal sub-temporal approach. One week postoperatively, the patient suffered a new SAH and was found to have developed a distinct basilar artery aneurysm. The patient was returned to the Operating Room for microsurgical clipping via the previous craniotomy. After surgery, the patient made a slow, but steady, recovery. She underwent repeated angiographic imaging, demonstrating a stable appearance. Two years post surgery, the patient had returned to work and had no obvious neurological deficit, with the exception of unilateral iatrogenic hearing loss.Conclusion:We describe a rare case of multiple aneurysms originating in relation to a mid-basilar dissection, resulting in multiple episodes of SAH. These are difficult and dangerous lesions that can be treated with open microsurgical reconstruction or possibly via an endovascular approach. The intricate location of the lesions poses a particular challenge to neurosurgeons attempting to directly treat mid-basilar lesions.

Background:During elective surgery for unruptured aneurysms, we have identified a group of patients with hemosiderin staining of the pial surface immediately adjacent to the aneurysm dome suggesting a remote and unrecognized history of microbleeding from the aneurysm. These cases form the basis for this report.Methods:Medical records of 421 unruptured cerebral aneurysm patients treated surgically between January 2003 and September 2010 were retrospectively reviewed. Patients with a history of prior subarachnoid hemorrhage, craniotomy, or significant closed head injury were excluded from review. Records were reviewed for intraoperative descriptions of hemosiderin deposition in the vicinity of the aneurysm as well as history of headaches, time to presentation, comorbidities, aneurysm characteristics, procedures, and radiologic imaging.Results:Local hemosiderin staining immediately adjacent to the aneurysm was identified intraoperatively in 13 cases. Each of these patients had a history of remote atypical headache prior to presentation. Eight of these patients (62%) had aneurysms described as particularly “thin-walled” at the time of surgery. Aneurysm locations included the internal carotid artery (ICA) (54%), middle cerebral artery (MCA) (23%), anterior communicating artery (ACOMMA) (15%), and the anterior cerebral artery (ACA) (8%). More than half (54%) of these patients had a history of smoking, while 31% had hypertension, and 23% had a history of alcohol abuse. Dyslipidemia and family history of aneurysms were present in 15% and hypercholesterolemia was noted in one patient (8%).Conclusion:We suggest this group of patients had suffered a “microbleed” resulting in local hemosiderin deposition next to the aneurysm. The origins and clinical implications of such microbleeds are unknown and warrant further investigation.