Introduction/purpose Cranial intradural dissecting pseudoaneurysms (DPAs) are rare but challenging entities associated with significant mortality and morbidity with limited literature on the endovascular management, mostly case reports. We report the outcomes of endovascular treatment in the largest series of cranial intradural DPAs.

Methods Retrospective review of our aneurysm patient was performed after IRB approval. All patients with spontaneous or traumatic cranial intradural DPAs were included. Exclusion Criteria were: 1) Extradural DPAs; 2) Isolated intracranial dissection with no associated pseudoaneurysm; 3) Infective (Mycotic) pseudoaneurysms.

Patient demographics, clinical presentation, aneurysm characteristics, treatment details, complications and outcomes based on follow-up imaging and clinical information was collected. Patients had immediate, short-term and long-term imaging follow-up to evaluate the effectiveness of the treatment using MRA or DSA or both. Clinical outcome was evaluated at the last known clinical follow-up based on modified Rankin Score (mRS).

Results A total of 24 patients with 25 dissecting pseudoaneurysms (DPAs) constituted our study population (M:F = 10:14; mean age 52.8 ± 13 years). Most patients had hemorrhagic presentation (88%;n = 21) with subarachnoid hemorrhage. Two patients had ischemic presentation and one DPA was incidental. 75% of the DPAs (n = 18) were located in the posterior circulation and 25% (n = 7) in the anterior circulation. The mean size of DPA was 6.3 ± 4.2 mm (range: 1.5–23 mm).

Parent vessel occlusion (PVO) was the most commonly used treatment modality (88%;n = 22) with variable use of coils (n = 17), liquid embolic agents (n = 4) or both (n = 1). Three patients had vessel preservation approach using coils (n = 1) and stent assisted coiling (n = 2). Extra-ventricular drain (EVD) was required in 88% patients. Ten patients (42%; Posterior DPAs: 7 and Anterior DPAs: 3) showed vasospasm refractory to the medical management, treated with intraarterial verapamil alone in 30% (n = 3) and with combination of intraarterial verapamil and balloon angioplasty in 70% (n = 7).

Procedural related complications were noted in 20% (n = 5) of study population (3: PICA infarcts; 1: M2 segment embolus and 1: ICA dissection).

The median long-term follow-up was 21 ± 26 months (0–96 months). Two patients were lost for the long-term follow-up. All 22 aneurysms treated with PVO remained occluded on short-term and long-term follow-up. The 3 aneurysms treated with vessel preservation demonstrated post treatment recanalization, with two requiring retreatment.

The mean duration up to the last known clinical follow-up was 22.3 ± 26.9 months. One patient (4%) was lost to clinical follow-up. Of the remaining 23 patients; 18 patients (78%) had mRS score of ≤ 1, three patients (13%) had mRS of 2 and one patient (4%) had mRS of 4 as a clinical outcome at the last known clinical follow-up. One patient died (4%) secondary to bacteremia and sepsis.

Conclusions Parent vessel occlusion (PVO) is a feasible, safe and effective treatment option in the treatment of cranial intradural dissecting pseudoaneurysms with a good long-term clinical outcome. Recanalization of the treated pseudoaneurysm is a potential risk especially in parent vessel preserving strategy, which warrants a close scrutiny with a short-term follow-up.

Disclosures S. Boddu: None. D. Kimball: None. M. Crimmins: None. A. Banihashemi: None. J. Knopman: None. P. Gobin: None. A. Patsalides: None.