Introduction: Delayed cerebral vasospasm with subsequent ischemic neurological deficit is a rare complication of elective clipping of unruptured intracranial aneurysms. Multiple pathophysiologic mechanisms have been postulated including endothelial dysfunction, intra-operative use of temporary clips and retractors, vasospastic mediators from hemolytic products or direct diffusion from the aneurysmal sac, hypothalamic injury, and the trigemino-cerebrovascular reflex. However, these mechanisms remain poorly understood especially with uncomplicated surgery with delayed onset of vasospasm and no evidence of post-operative subarachnoid hemorrhage.

Methods: We reviewed the clinical data and imaging from the index case and conducted a systematic review of the medical literature using PUBMED and keywords. We reviewed the bibliographies of each result to identify additional papers and continued this iterative method of review until the process exhausted. Publications pre-dating the CT era or those that could not exclude peri-operative subarachnoid hemorrhage were excluded.

Results: We identified only seven references describing the diagnosis of and management of cerebral vasospasm in a total of ten patients from 1980-2016. Of these patients, there was only one male. The mean age was 52.7, and half of patients were symptomatic on discovery of the aneurysm. Half of the aneurysms were located in the ICA with the remainder in the MCA. Sizes ranged from 4-7mm, with our patient’s aneurysm approximating 6mm. Time to onset of vasospasm ranged from 2-28 days. Most common deficits included hemiparesis (60%) and aphasia (80%). 6 patients received triple H therapy with 5 of these cases achieving full neurologic recovery. Our patient received a similar regimen with full recovery in 6 weeks.

Conclusions: Early recognition of delayed cerebral vasospasm is crucial to reversal of ischemic neurologic deficit after elective aneurysm repairs. No single etiologic factor has been identified although the ICA/MCA are the most common locations. Further research into vasospasm is needed to understand the mechanism.

Patient Care: Although delayed cerebral vasospasm is a rare event after elective aneurysm clipping, prompt identification and treatment is essential.

Learning Objectives: 1. Recognize the symptoms of vasospasm following elective clipping of unruptured intracranial aneurysms and select confirmatory test modalities. 2. Describe the known etiological risk factors for vasospasm following clipping of unruptured intracranial aneurysms. 3. Implement treatment to reverse the effects of vasospasm following clipping of unruptured intracranial aneurysms.

References: Cerebral vasospasm and delayed ischemic deficit following elective aneurysm clipping Tsyben A case of unexpected symptomatic vasospasm after clipping surgery for an unruptured intracranial aneurysm Hashimoto Clinical and angiographical delayed cerebral vasospasm after uncomplicated surgical clipping of unruptured intracranial aneurysms: Illustrated review and two case reports Yang Cerebral vasospasm in patients with unruptured intracranial aneurysms Paolini Postoperative vasospasm of unruptured paraclinoid carotid aneurysms: Analysis of 30 cases Kitazawa Unruptured aneurysm: vasospasm after surgery and endovascular treatement Gutierrez Delayed cerebral vasospasm after uncomplicated operation on an unruptured aneurysm: Case Report Bloomfield