Dynamic perfusion CT: Optimizing the temporal resolution for the calculation of perfusion CT parameters in stroke patients

CT Perfusion in Acute Ischemic Stroke: A Comparison of 2-Second and 1-Second Temporal Resolution

“…11,12,19 Despite these differences, corresponding 2-second and 1-second TR lesion sizes showed very good agreement in our study. We found a trend toward slightly decreased CBF DC lesion extent (which is in agreement with findings by Kämena et al 13 ). Most important, therapeutic decisions would not have been altered by these differences in any of the cases.…”

“…For deconvolution algorithms, studies by Wintermark et al 11 and by Wiesmann et al 12 indicated that a reduced TR of only 1 image per 4 seconds might be feasible. However, studies by Kämena et al 13 (by using the Perfusion 3 software package, GE Healthcare, Milwaukee, Wisconsin) and Kloska et al 9 (by using the MS algorithm, Neuro Perfusion, Siemens) indicated that a TR of 2 images/1 second or 1 image/1 second, respectively, should be used to achieve the best detection and depiction of ischemic areas. Different scan protocols (milliampere-second, kilovolt[peak]), patient cohorts, software packages, deconvolution algorithms, pre-and postprocessing settings, and TAR/NVT thresholds used in these studies make it hard to interpret and compare the results.…”

“…11 Discordant findings regarding the feasibility of reduced TR have been reported in the literature. 9,[11][12][13] The purpose of our study was to evaluate the feasibility of a reduced TR scan protocol using a 2-second TR versus the standard TR of 1-second, by using 2 different algorithms (least mean squares DC and MS).…”

Reproducibility and variability of very low dose hepatic perfusion CT in metastatic liver disease

“…Ng et al (28) reported that an optimal perfusion data might be based on high temporal sampling for the first 30 s and low temporal sampling for the second phase. Several other studies also have found that sampling interval up to 2 s can allow reproducible pCT parameters (20,25,30). Thus, we kept the cycle time as low as possible (1 s) for the first 20 s and then gradually increased.…”

Multiphase CT Angiography versus Single-Phase CT Angiography: Comparison of Image Quality and Radiation Dose

“…Wintermark et al 17 concluded that temporal sampling intervals Ͼ1 second can be used without altering the quantitative accuracy of PCT with an increase of iodinated contrast material. In a recent study, Kamena et al 18 recommended a temporal scanning resolution of 2 images per second for the best detection and depiction of ischemic areas. In a continuous acquisition (cine) mode, the patient's radiation dose would be the same by using a sampling interval of either 1 or 0.5 second.…”