Computed tomography (CT) perfusion is a useful technique that enables the differentiation of salvageable ischemic penumbra from infarct core and can help identify patients most likely to benefit from acute revascularization therapies. The high radiation dose received from continuously scanning one location of the head during the first pass of iodinated contrast material has been a focus of interest to many articles [1, 2]. Reduction in tube current and tube voltage and the use of iterative reconstruction can lead to a remarkable reduction in the...

Patient population Ten patients (5 men and 5 women; mean age, 82.9 years) who had undergone non-contrast CT, CT perfusion, and CT angiography as part of the standard acute stroke assessment from April 2016 to February 2019 were enrolled in this retrospective study. The occlusion regions were as follows: internal carotid artery, 5 patients; and proximal segment (M1) of the middle cerebral artery, 5 patients. All patients had successful recanalization defined by the thrombolysis in cerebral infarction (TICI) scale 3 via mechanical thrombectomy. This study...

Noise levels (SD) of CT perfusion data at each dose level were as follows: 75 mAs, 11.2±1.1; 60 mAs, 12.5±1.2; 45 mAs, 14.4±1.4; 30 mAs, 17.7±1.7; and 15 mAs, 25.0±2.4. The quantitative values of each CT perfusion parameter at different dose levels in the affected and contralateral normal regions are summarized inTable 1 . All quantitative values of the low-dose CT perfusion data sets at the tube current-time product of 60 and 45 mAs were comparable with those of the original CT perfusion data (p>0.05...

We simulated low-dose CT perfusion data sets and compared the quantitative perfusion values at low doses with those obtained at the original dose using the Bayesian estimation algorithm. Our results revealed that all quantitative perfusion parameters acquired at 60 and 45 mAs were not different from those at 75 mAs in both affected and contralateral normal regions. Thus, a reduction in the tube current-time product down to 45 mAs can yield sufficient image quality in CT perfusion analysis with the Bayesian estimation algorithm. A previous...

Shota Ichikawa, RT Department of Radiological Technology, Kurashiki Central Hospital 1-1-1 Miwa, Kurashiki, Okayama, 710-8602 Japan Phone: +81-86-422-0210 E-mail:[email protected] -nothing to disclose

1.Hoang JK, Wang C, Frush DP, et al (2013) Estimation of radiation exposure for brain perfusion CT: standard protocol compared with deviations in protocol. AJR Am J Roentgenol 201:W730-4. 2.Wintermark M, Lev MH (2010) FDA investigates the safety of brain perfusion CT. AJNR Am J Neuroradiol 31:2–3. 3.Othman AE, Afat S, Brockmann MA, et al (2016) Radiation dose reduction in perfusion CT imaging of the brain: A review of the literature. J Neuroradiol 43:1–5. 4.Sasaki M, Kudo K, Boutelier T, et al (2013) Assessment of...