Introduction Intracranial pseudoaneurysms encompass less than 1% of all intracranial arterial lesions. Most commonly, they may develop secondary to head injury, vasculopathy, infection or iatrogenic causes. Idiopathic cases are very uncommon and/or rarely diagnosed. We describe seven cases of idiopathic Anterior Cerebral Artery (ACA) pseudoaneurysms that were diagnosed over the last two years at our institution, and offer our unique perspective on the overall management of these difficult to treat lesions.
Methods The hospital database for neuroendovascular procedures was searched over a two-year period (2011-2013) in order to identify patients with a diagnosis of pseudoaneurysms. The search was further narrowed to identify patients with a diagnosis of ACA pseudoaneurysms. A retrospective chart review then ensued to gather information on patient demographics, imaging characteristics, treatment course, and type of pseudoaneurysm. Only idiopathic cases of pseudoaneurysm formation were included.
Results The database generated seven patients, 4 males and 3 females. Mean age was 51.2 years. In all seven cases, an endovascular approach was initially attempted to embolise the lesion. Four patients had successful endovascular treatments with continued occlusion on long-term follow-up. Two of these 4 patients were treated with coil embolisation and two with flow-diversion. The fifth patient required multiple coil embolisations due to the recurrent nature of the lesion with ultimate obliteration. The sixth patient had multiple coil embolisations with continued recurrence and was definitively treated with surgical clipping. The endovascular repair failed in the seventh patient due to the complex anatomy of the lesion and severe proximal vasospasm. This patient was also deemed inappropriate for clipping due to how fragile the lesion appeared at surgery. Therefore, this lesion was successfully surgically trapped.
Conclusion Idiopathic ACA pseudoaneurysms may be an under-recognised entity. The treatment is often difficult and many of the lesions are associated with unfavourable anatomy. Due to the surgical technical difficulty and complex anatomy of these lesions, an endovascular approach may be attempted first in order to treat the lesion. However, open surgical treatment should be considered in a timely fashion if endovascular repair is unable to obliterate these pseudoaneurysms. Limitations of endovascular embolisation include lesion re-growth after coiling and potential need for stents in the setting of subarachnoid haemorrhage. If the endovascular route is unsuccessful, open vascular clipping should be considered. If direct clipping is not feasible due to the anatomy/friability of the lesion, then surgical trapping should be considered if collateral flow from contralateral vessels is appreciated. Non-surgical management has a limited role, given the likelihood of lesion growth and high rates of rupture.
Disclosures A. Patel: None. D. Gandhi: None. E. Aldrich: None. M. Simard: None. B. Aarabi: None. G. Jindal: None.