Improved Computed Tomography Imaging Post-Flow Diverter Treatment Using a SOMATOM X.Cite Scanner.

Objective: Treatment with flow diverters requires follow-up imaging. Conventional CT suffers from beam-hardening artifacts caused by the stent, complicating the evaluation. This study introduced the SOMATOM X.cite (Siemens Healthineers, Forchheim, Germany) scanner to improve imaging quality for stent follow-up and examined its image output (stent condition). Methods: From January 2021 to April 2024, 27 patients treated with flow diverters were imaged using SOMATOM X.cite, conventional CT, and the ARTIS icono D-Spin system (Siemens Healthineers). The aneurysm locations included the internal carotid artery-specifically, 11 cases in the paraclinoid segment and 8 in the cavernous segment, as well as the vertebral artery in 8 patients. The aneurysm sizes were ≥10 mm (14 cases) and 5-10 mm (13 cases). The image quality of the stented parent artery was subjectively scored on a 2-point scale, adapted from a previous report in which a 3-point scale had originally been used, as follows: 1 = moderate (evaluation could be made but information was lacking compared with DSA), and 2 = good (image could be evaluated similarly to DSA). Results: Compared with conventional contrast-enhanced CT, the SOMATOM X.cite significantly reduced beam-hardening artifacts around the stent. In 26 of 27 cases, stent-condition CT images acquired with the SOMATOM X.cite were rated as 2 (good), providing clear visualization of the stent lumen and similar in quality to cone-beam CT. One case had reduced contrast, making aneurysm visualization difficult. In comparison, 27 conventional CT images were rated 1 (moderate). Conclusion: The SOMATOM X.cite scanner provided high-quality imaging comparable to cone-beam CT; thus, it may be a useful tool for follow-up evaluation after flow diverter stenting.