Impact of Aneurysmal Subarachnoid Hemorrhage Severity on Contrast Media Arrival Time in Head Computed Tomography Angiography.

Aim This study aims to evaluate the effect of subarachnoid hemorrhage (SAH) severity on contrast media (CM) arrival time in head computed tomography angiography (CTA) at SAH onset. Method A total of 67 patients who underwent head CTA were evaluated; 41 patients developed SAH (SAH group), and 26 patients had suspected unruptured cerebral aneurysms (non-SAH group). The patients of the SAH group were divided into mild (grades I-III), semi-severe (grade IV), and severe (grade V) groups according to Japanese guidelines. CM arrival time was measured for each case. Results The CM arrival time increased with SAH severity. The semi-severe and severe groups exhibited significantly longer CM arrival times compared to the non-SAH group (non-SAH: 11.1 ± 2.03, mild: 13.2 ± 2.97, semi-severe: 15.8 ± 3.45, severe: 16.6 ± 3.40). Conclusion The CM arrival time increases with SAH severity in head CTA at SAH onset. Therefore, it is important for operators to be aware of the possibility of slower-than-usual timing in severe cases of SAH.