Abstract Number ‐ 42: Patterns of Alert and Management of Cerebral Aneurysms using an Incidental Aneurysm Alert System (IAAS)
Authors: Fukuda Keiko A , Ghochani Yasmin , Enzmann Dieter , Arnold Corey , Chen Xiang , Morales Jose , Kimball David , Beaman Charles , Duckwiler Gary , Jahan Reza , Tateshima Satoshi , Szeder Viktor , Colby Geoff , Kaneko Naoki , Nour May 
Published: April 2023

Introduction
Incidentally discovered cerebral aneurysms have become an increasingly more common finding as patients undergo more frequent surveillance imaging. To aid in clinical management of these critical findings, we sought to develop an automated alert system for these vascular lesions. Here we describe the effectiveness of the alert system and subsequent management of incidentally discovered cerebral aneurysms on MR or CT angiography using an Incidental Aneurysm Alert System (IAAS).

Methods
IAAS received neuroradiology reports of MRA and CTA generated by the UCLA Department of Radiology via an HL7 feed. Reports were parsed using natural language processing to identify mentions of ‘aneurysm’. Each identification automatically generated an alert email to the interventional neuroradiology division for physician triage. Indication for imaging, specialty of ordering physician, aneurysm location and size, aneurysm development risk factors, PHASES score, patient ethnic background and subsequent management of vascular lesion were assessed.

Results
A total of 129 consecutive reports were reviewed from March‐December of 2020. Ten duplicate patients were excluded. Of the unique reports, 5 alerted for non‐vascular lesions and 7 did not demonstrate an aneurysm after additional imaging, resulting in a 90% detection accuracy of suspected cerebral aneurysms for a total of 107 unique cases included in the analysis. The median age was 65 years and 65% were female. Self‐identified race was 54% non‐Hispanic White, 20% other, 8% Asian, 6% Black, and 6% unknown/declined to answer. One quarter (25%) were of Hispanic ethnicity. The most common indication for imaging was acute stroke (27%). Of the detected aneurysms, 48% resulted in consultation with a neuro‐interventionalist. Of the referrals generated, 75% originated from a hospital facility and 25% from community practice. The most common referring specialty was Neurology (37%). Of those referred, just over 50% subsequently underwent diagnostic and/or therapeutic angiography. Seventy three percent of patients who underwent cerebral angiography were intervened upon either immediately or within 2 years from discovery. Eight percent of detected aneurysms were ruptured on presentation. Aneurysms were treated with flow diversion (37%), primary coiling (37%), clipping (16%) and vessel sacrifice/surgical trapping (10%). The mean PHASES score of all patients referred was 4.5, conferring a 5‐year rupture risk of ∼0.9‐1.3%. Asian and Hispanic populations had higher mean PHASES scores on presentation of 7.2 (∼2.4% 5‐year rupture risk) and 5.2 (∼1.3% 5‐year rupture risk) respectively, compared with Non‐Hispanic Caucasians of 4.1 (∼0.9% 5‐year rupture risk). For Hispanics, mean age was 54 years and mean aneurysm size 9.5 mm as compared to 65 years and 5.7 mm in non‐Hispanic Caucasians on presentation. There were no significant differences in aneurysm risk factors including HTN, smoking, fibromuscular dysplasia or family history of cerebral aneurysms.

Conclusions
IAAS is an effective method of alerting neuro‐interventionalists of incidentally identified cerebral aneurysms. Of those detected in our pilot series, Hispanics were younger with larger aneurysms on detection. IAAS may have potential value in connecting general physicians with cerebrovascular specialists, improving the management of patients with incidentally discovered cerebral aneurysms.