Fast acquisition cone-beam computed tomography: initial experience with a 10 s protocol

Background Cone-beam computed tomography (CBCT) facilitates the acquisition of cross-sectional imaging in angiography suites using a rotational C-arm and digital flat panel detectors. The applications are numerous, including evaluation of implanted devices and localization of cerebrovascular lesions. We present and validate the clinical utility of an alternative fast CBCT acquisition protocol in the context of neurovascular device imaging. Methods Contrast-enhanced (CE)-CBCT images were acquired using a new 10s protocol in a phantom head model, swine model, and in patients. The acquisition parameters of both the 10 s and 20s protocols were exactly the same, except for fewer projections (250 projections in 10s vs 500 projections in 20s), resulting in reduced scan time. Image quality was measured quantitatively in a controlled phantom study and qualitatively by blinded reviewers. The latter was performed to assess the image quality of the 10s protocol pertinent to the device visibility and its apposition to the parent artery. Results 10s CBCT images were comparable to 20s CBCT in both phantom and animal studies. Of the 25 patient images, the reviewers agreed that they were able to discern the flow diverter struts and assess the apposition in all images. The overall rating for all 10s images was 4.28 on a 5-point scale. No images were rated as less than 3, which was the average diagnostic quality. The ratings were concordant across three blinded reviewers (=0.411). Additionally, contrast and spatial resolution between 10s and 20s images were similar in non-human models. Conclusions CBCT images of neurovascular devices can be obtained successfully using a 10s acquisition protocol. In addition, the 10s protocol offers faster acquisition, thus allowing its use in awake patients and with an added advantage of lower radiation and contrast dose.