Changes of Time-Attenuation Curve Blood Flow Parameters in Patients with and without Carotid Stenosis

Abstract

BACKGROUND AND PURPOSE:From the time-attenuation curves of DSA flow parameters, maximal intensity, maximal slope, and full width at half maximum of selected vascular points are defined. The study explores the reliability of defining the flow parameters by the time-attenuation curves of DSA.

Peritherapeutic Hemodynamic Changes of Carotid Stenting Evaluated with Quantitative DSA in Patients with Carotid Stenosis

“…The study of Lin et al showed significant change at M1 and M2 only. 10 Our study showed significant changes for all arterial ROIs except A2. The discrepancy in maximal slope (WI in our Results for the hemodynamic parameters with significant changes (P < .05) after the stenting procedure in the PA view study) and FWHM is most likely caused by the difference in calculation algorithm.…”

“…Lin et al 10 reported a study of cerebral circulation time by calculating the rTTP relative to the cervical ICA on the PA view (same location as ICA 1 in our report) and relative to the cavernous segment of the ICA on the lateral view (same location as ICA 2 in our report). We found that the poststenting mean circulation times of M1, M2, and PV (corresponding to rTTP of the following segments: ICA 1 -M1, ICA 2 -M2, and ICA 2 -PV) in our study (0.49, 0.50, and 4.14 seconds, respectively) were close to those of healthy controls (0.46, 0.58, and 4.38 seconds, respectively).…”

“…We found that the poststenting mean circulation times of M1, M2, and PV (corresponding to rTTP of the following segments: ICA 1 -M1, ICA 2 -M2, and ICA 2 -PV) in our study (0.49, 0.50, and 4.14 seconds, respectively) were close to those of healthy controls (0.46, 0.58, and 4.38 seconds, respectively). 10 Therefore, the cerebral circulation time returned to normal for M1, M2, and the PV after treatment. If the posttreatment cerebral circulation time does not decrease to normal, we have to consider a hemodynamically significant residual stenosis, arterial spasm, hidden tandem stenotic lesion, and microemboli.…”

“…Curve fitting in our study made the timeconcentration curve smooth; thus, the measured slope may be less than the maxillary slope obtained without curve fitting in the previous study. 10 We evaluated the BAT in intracranial vascular points. The BAT was first used to make a color-coded image from angiograms obtained by 1 contrast media injection.…”

“…10 Maximal slope and full width at half maximum (FWHM) are found to complement rTTP in the evaluation of cerebral circulation. 10 Furthermore, the area under the curve (AUC) of the proximal common carotid arteries can be calculated from the time-concentration curves of color-coded DSA. A good correlation was found between the AUC and the relative CBV obtained from flat panel detector CT by injecting contrast medium into the ascending aorta.…”