Reduction of misregistration on cerebral four-dimensional computed tomography angiography images using advanced patient motion correction reconstruction.

PURPOSE: The aim of this study was to evaluate whether advanced patient motion correction (APMC) can reduce the misregistration of pixels between the different X-ray tube positions in four-dimensional CT angiography (4D-CTA).

MATERIALS AND METHODS: Eight patients with intracranial aneurysms were included in this retrospective study. We compared the CTA images with APMC reconstruction and half-scan reconstruction with regard to the following 3 items: (1) bone misalignment area; (2) image noise; and (3) aneurysm volume change.

RESULTS: The bone misalignment area and image noise were significantly reduced in the APMC images, as compared to that in the half-scan reconstruction images (bone misalignment area: 33.0 ± 18.1 cm(3) vs 152.0 ± 72.2 cm(3), respectively; p < 0.001) (image noise at pons: 9.70 ± 2.58 vs 15.16 ± 5.02, respectively, p < 0.001). The aneurysm volume and volume variance were significantly smaller in the APMC reconstruction than those in the half-scan reconstruction (volume: 1107.2 ± 1813.8 mm(3) vs 1135.1 ± 1853.8 mm(3); p < 0.05; coefficient of variation: 0.0291 ± 0.014 vs 0.0463 ± 0.026, p < 0.05, respectively).

CONCLUSION: Our results show that APMC reduces the reconstruction related misregistration between the cardiac phases compared to half-scan reconstruction.