Increased image quality and reduced radiation dose and contrast media volume: a holistic approach to intracranial CTA

AIM: To investigate the doseelength product (DLP) during intracranial computed tomography angiography (CTA) using a patient-specific contrast formula. MATERIALS AND METHODS: Intracranial CTA was performed on 120 patients using 64-channel CT. Patients were subjected in equal numbers to one of two acquisitions/contrast medium protocols. Protocol A, consisted of 80 ml contrast medium and protocol B, involved a novel contrast medium formula. In each protocol, contrast medium and saline were injected at a flow rate of 4.5 ml/s. The DLP and contrast volume (CV) were measured between each protocol and the data obtained were compared using two-tailed independent t-test. RESULTS: Mean arterial vessel attenuation was up to 56% (p<0.01) higher using protocol B compared with A. In the venous system, the mean vessel attenuation was significantly lower in protocol B than A with a maximum reduction of 93% (p<0.001). The mean CV was significantly lower in protocol B (53 +/- 10 ml) compared to A (80 +/- 1 ml, p<0.001). The scan time was equal in each protocol (B, 4.22 +/- 1.2 seconds; A, 4.01 +/- 1.3 seconds). A significant reduction in mean DLP was demonstrated in protocol B (3.99 +/- 0.22 mSv) compared to A (4.74 +/- 0.22 mSv; p = 0.02). CONCLUSION: A significant reduction in CV and DLP during intracranial CTA can be achieved when employing a patient-specific contrast medium formula. (C) 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.