The hypoattenuating berry sign: a reliable marker for ruptured aneurysms in subarachnoid hemorrhage patients with multiple aneurysms.

Background and purpose: Non-enhanced computed tomography (NECT) and computed tomography angiography (CTA) are useful for detecting aneurysmal subarachnoid hemorrhage (SAH) but challenging to identify ruptured aneurysms in cases of multiple aneurysms. We aimed to determine if the hypoattenuating berry sign (HBS) can identify ruptured aneurysms in SAH patients with multiple aneurysms.

Methods: Patients who had multiple aneurysms and underwent NECT were retrospectively recruited. The HBS, blood score, size and location of aneurysm were independently analyzed. The attenuation value of HBS and surrounding SAH were recorded. The independent factors of HBS in determination of ruptured aneurysms were analyzed using multivariable logistic regression.

Results: Fifty-three patients (mean age 64.2 ± 10.9 years, 83.0% female) with 112 aneurysms were enrolled. In the univariate analysis, aneurysm size, aneurysm status (ruptured), and blood score were significantly correlated with the occurrence of HBS. In the multivariate analysis, only aneurysm status showed a significant association with HBS. Aneurysms with HBS were larger than those without (6.8 ± 4.2 mm versus 4.2 ± 1.2 mm, P < 0.001), and those measured via NECT were larger than those measured via DSA (7.2 ± 3.8 mm vs. 6.8 ± 4.2 mm, P < 0.001). HBS was found in 51.8% of all aneurysms and in 87.7% of ruptured aneurysms on NECT. Raters had high agreement on aneurysm size (ICC = 0.829), HBS presence (kappa = 0.928), and blood score (kappa = 0.780).

Conclusions: The HBS can be used to detect ruptured aneurysm in patient with SAH and multiple aneurysms.