Optimal scan timing for artery–vein separation at whole-brain CT angiography using a 320-row MDCT volume scanner

Abstract

Objective: A 320-row multidetector CT (MDCT) is expected for a good artery-vein separation in terms of temporal resolution. However, a shortened scan duration may lead to insufficient vascular enhancement. We assessed the optimal scan timing for the artery-vein separation at whole-brain CT angiography (CTA) when bolus tracking was used at 320-row MDCT. Methods: We analyzed 60 patients, who underwent whole-brain four-dimensional CTA. Difference in CT attenuation between the internal carotid artery (ICA) and the superior sagittal sinus (D att ) was calculated in each phase. Using a visual evaluation score for the depiction of arteries and veins, we calculated the difference between the mean score for the intracranial arteries and the mean score for the veins (D score ). We assessed the time at which the maximum D att and D score were simultaneously observed. Results: The maximum D att was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s and 18.0 s in the venous-dominant phase after the contrast media arrival time at the ICA (T aa ). The maximum D score was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s in the venous-dominant phase after the T aa . There were no statistically significant differences in D att (p 5 0.375) or D score (p 5 0.139) between these scan timings. Conclusion: The optimal scan timing for artery-vein separation at whole-brain CTA was 6.0 s or 8.0 s for the arteries and 16.0 s for the veins after the T aa . Advances in knowledge: Optimal scan timing allowed us to visualize intracranial arteries or veins with minimal superimposition.

Optimal placement of the region of interest for bolus tracking on brain computed tomography angiography in Beagle dogs

“…In our study, the degree of venous contamination was qualitatively assessed using VR images. In human medicine, one study considered the superior sagittal sinus to be representative of the vessels and analyzed artery-vein separation using CT angiography [25]. The study examined both the arterialdominant and venous-dominant phases based on a total examination duration of 60 sec.…”

Validation of SART 3.5D algorithm for cerebrovascular dynamics and artery versus vein classification in presurgical 3D digital subtraction angiographies

“…Importantly, it was a fully standard protocol used in preparation to brain surgery (Cardinale et al 2015), i.e. no extra Rx exposure, CM dosage, and scan time was required, diversly from other methods (Matsumoto et al 2005, Mendrik et al 2010, Laue et al 2013, Havla et al 2015, Shirasaka et al 2017, Meijs and Manniesing 2018.…”

“…This technique consists in a dynamic acquisition protocol based on multiple gantry rotations which capture a sequence of 3D volumes over time, associating to each vascular voxel a Time Intensity Curves (TIC) describing the CM dynamic. Needless to say that these high-end multi-detector row CT scanners are based on highly demanding equipment and protocols requiring higher acquisition time which increases the dosage of CM and radiation exposure (Matsumoto et al 2005, Mendrik et al 2010, Laue et al 2013, Havla et al 2015, Shirasaka et al 2017, Meijs and Manniesing 2018.…”

Image-quality characteristics in the longitudinal direction from different image-reconstruction algorithms during single-rotation volume acquisition on head computed tomography: A phantom study

“…The usefulness of single-rotation volume scanning within a short time in CT angiography has been reported for the head in pediatric patients and for cerebral vessels and coronary arteries. [1][2][3][4][5][6] Volume scanning is also used in perfusion CT and four-dimensional CT in which the same area is imaged in a time series by successive single-rotation volume acquisition. 2,[7][8][9] When performing a single-rotation volume scan, a fixed radiation dose is used in whole-head CT because automatic exposure control is not applicable.…”