O-001 3D aneurysm wall enhancement is associated with symptomatic presentation

Abstract

<h3>Introduction/Purpose</h3> Aneurysm wall enhancement (AWE) is a potential surrogate biomarker for aneurysm instability. Previous studies have assessed AWE using 2D multiplanar methods, most of which were conducted qualitatively. A new quantitative tool to map 3D-AWE of brain aneurysms was studied on a large cohort of patients. <h3>Materials and Methods</h3> Saccular aneurysms were imaged prospectively with 3T high resolution magnetic resonance imaging (HR-MRI). AWE patterns of symptomatic and asymptomatic aneurysms were analyzed with our 3D-AWE pipeline. Symptomatic aneurysms were defined as ruptured, presentation with sentinel headache, and presentation with cranial nerve neuropathy. Aneurysms were segmented and orthogonal probes were extended into the aneurysm wall to create 3D-AWE maps. <b>(Figure 1).</b> Three metrics were used to characterize enhancement: 3D circumferential AWE (3D-CAWE), aneurysm-specific contrast uptake (SAWE), and focal AWE (FAWE). Aneurysms with a circumferential AWE higher than the corpus callosum (3D-CAWE ≥ 1) were classified as 3D-CAWE+. Symptomatic presentation was predicted with univariate and multivariate logistic models. Aneurysm size, size ratio, aspect ratio, irregular morphology, and PHASES and ELAPSS scores were compared with the new AWE metrics. Compartmental bleb analysis and identification of microhemorrhages were also performed. <h3>Results</h3> Ninety-three aneurysms were analyzed. Univariate analysis showed that 3D-CAWE, SAWE, and FAWE are predictors of symptomatic status (OR = 1.34, 1.25, and 1.08 respectively). A multivariate model including aneurysm size, 3D-CAWE+, age, female sex, and FAWE predicted symptomatic status with 80% specificity and 90% sensitivity (AUC = 0.914, NPV = 0.967). FAWE was also associated with irregular morphology and high-risk location (<i>p</i> = 0.043, <i>p</i> = 0.001 respectively). In general, blebs enhanced 56% more than the aneurysm body. Areas of microhemorrhage colocalized with increased SAWE (<i>p</i> = 0.047). <h3>Conclusions</h3> Analysis of enhancement with 3D-AWE maps provides a new set of metrics that could potentially improve the identification of symptomatic aneurysms. <h3>Disclosures</h3> <b>A. Raghuram:</b> None. <b>S. Sanchez:</b> None. <b>L. Wendt:</b> None. <b>S. Cochran:</b> None. <b>D. Ishii:</b> None. <b>C. Osorno-Cruz:</b> None. <b>G. Bathla:</b> None. <b>T. Koscik:</b> None. <b>J. Torner:</b> None. <b>D. Hasan:</b> None. <b>E. Samaniego:</b> None.