Multidetector CT Perfusion Research Articles

Angiography suite cone-beam CT perfusion for selection of thrombectomy patients: A pilot study.

Background and PurposeThe availability of cone‐beam CT perfusion (CBCTP) in angiography suites may improve large‐vessel occlusion (LVO) triage and reduce reperfusion times for patients presenting during extended time window. We aim to evaluate the perfusion maps correlation and agreement between multidetector CT perfusion (MDCTP) and CBCTP when obtained sequentially in patients undergoing endovascular therapy.MethodsThis is a prospective, pilot, single‐arm interventional cohort study of consecutive patients with anterior circulation LVO. All patients underwent MDCTP and CBCTP prior to endovascular therapy, generating cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time‐to‐maximum/time to peak contrast concentration maps. We compared the two imaging modalities using three different methods: (1) six regions of interest (ROIs) placed in the anterior circulation territory; (2) ROIs placed in all 10 Alberta Stroke Program Early CT Score regions; and (3) ROI drawn around the entire ischemic area. ROI ratios (unaffected/affected area) were compared for all sequences in each method. We used the intraclass correlation coefficient to calculate the correlation between the studies. Bland‐Altman plots were also created to measure the degree of agreement. Finally, a sensitivity analysis was done comparing both modalities in patients with low infarct growth rate.ResultsFourteen patients were included (median age 81 years [74‐87], 50% males, median National Institutes of Health Stroke Scale 19 [14‐22]). Median time between studies was 42 minutes (interquartile range 29‐61). Independently of the method used, we found moderate to excellent correlation in CBF, CBV, and MTT between modalities. CBF correlation further improved in patients with low infarct growth.ConclusionThese results demonstrate promising accuracy of CBCTP in evaluating ischemic tissue in patients presenting with LVO ischemic stroke.

Abstract TP76: Quantitative Comparison of Multidetector CT and Cone-Beam CT Perfusion Maps in Large Vessel Occlusion Stroke Patients Undergoing Mechanical Thrombectomy

Cerebral perfusion evaluation using CT or MR perfusion is the gold standard modality to select large vessel occlusion (LVO) stroke patients presenting >6 hours from symptom onset. The availability of cone beam C-arm CT perfusion (CBCTP) in angiography suites could reduce time to endovascular revascularization. We aimed to evaluate the reliability of using CBCTP when compared to multidetector CT perfusion (MDCTP). In this prospective, single-arm, interventional study, 14 LVO anterior circulation thrombectomy patients underwent both a 128 slice MDCTP in the ED and a CBCTP <30 minutes apart prior to groin puncture. CBCTP was acquired using a prototype acquisition mode enabling 10 consecutive C-Arm rotations with nearly continuous data acquisition. A total of 60 cc of contrast layered with 60 cc of saline were injected covering arterial inflow, parenchymal phase and venous outflow. Image data was reconstructed into CBF, CBV, MTT and TTP maps. Three types of measurements were used to compare modalities. In measurement 1, 6 circular regions of interest (ROI) (400mm 2 ) were placed in the anterior arterial territory. In measurement 2, circular ROIs were placed in the ASPECTS regions (cortical 300mm 2 , subcortical 200mm 2 ). In measurement 3, a ROI was drawn around the entire affected area. All ROIs were placed in the basal ganglia and supraganglionic level of both brain sides. Rates (unaffected/affected area) between MDCTP and CBCTP were compared for all sequences. The intraclass correlation coefficient (ICC) was calculated using a single rater, consistency, two-way random-effects model. Measurement 1 found a moderate degree of agreement between MDCTP and CBCTP in CBF, CBV, MTT and TTP rates with ICCs of 0.58 (CI 0.42 - 0.69), 0.65 (CI 0.53 - 0.74), 0.77 (CI 0.68 - 0.83) and 0.52 (CI 0.35 - 0.65). In measurement 2, moderate agreement was found in CBF, CBV and MTT rates; with ICCs of 0.51 (CI 0.32 - 0.65), 0.57 (CI 0.4 - 0.69) and 0.62 (CI 0.47 - 0.73). The results of measurement 3 found an excellent (ICC=0.95, CI 0.88 - 0.98), good (ICC=0.83, CI 0.62 - 0.9) and moderate (ICC=0.7, CI 0.34 - 0.87), degree of agreement in the CBV, MTT and CBF rates, respectively. These results demonstrate promising accuracy of CBCTP in the evaluating ischemic tissue in patient presenting with LVO acute stroke.

Multi-detector CT perfusion as a diagnostic imaging modality to evaluate local therapy of hepatocellular carcinoma

ObjectiveTo evaluate MDCT perfusion role in HCC local therapy response. Patients and methodsPost radiofrequency ablation and trans-arterial chemoembolization 14 (88%) male and 2 (12%) female HCC patients; with the mean age, 55.75±10.6years underwent follow-up hepatic CT perfusion. The hepatic arterial and portal venous perfusions (HAP and HPP, ml/min/100ml) and hepatic perfusion index (HPI%) were indicated using the color coded maps to assess the effects of local therapy on hepatic perfusion values. ResultsThe post local treatment CTP of the recurrent tumor confirmed relative increased HAP and HPI and reduced PVP relative to the background values of the cirrhotic hepatic parenchyma. The recurrent HCC post-treatment CTP including HAP is 71±12.19, the PVP is 25.5±8.66 and HPI is 52.5±11.9. The post local-treatment CTP of the necrosis confirmed relative decreased HAP and HPI and increased PVP. The post-treatment necrosis CTP including HAP is 23±10.39, the PVP is 34.75±11.5 and HPI is 29±16.51. The CTP sensitivity is 75%, specificity 50% and P-value <0.05. ConclusionCTP is a promising non-invasive technique assessing the efficacy, predicting early response to local treatment therapies and monitoring tumor recurrence. It assesses the degree of post therapy tumor perfusion especially the degree of arterialization.

Evaluation of an Acute Stroke Patient with Flat Detector CT Prior to Mechanical Thrombectomy

Flat panel detectors have revolutionized tomographic imaging in the angio suite. Recent developments in hardware and software have improved soft tissue resolution and acquisition time even further, enabling soft-tissue and perfusion imaging within the angio suite. The so called “one-stop-shop” stroke imaging with flat panel detector computed tomography (FDCT) will significantly improve door to groin times and probably have an impact on patient outcome. In the presented case a patient underwent multidetector CT (MDCT) to exclude hemorrhage, then MDCT angiography (MDCTA) to identify the occluded vessel, and MDCT perfusion (MDCTP) for penumbra imaging. Patient’s symptoms significantly improved during transport to the angiography suite. Thus, prior to intervention, multimodal FDCT with vessel and perfusion imaging was acquired and ultimately led to cancelation of the interventional therapy. In this clinical scenario, multimodal FDCT imaging can provide quick answers and eliminate the risk of an invasive angiography in cases of reperfusion prior to mechanical thrombectomy.

Comparison of Diagnostic Usefulness of Multi-Channel CT Perfusion and Conventional Brain CT in the Acute Pontine Infarct

Copyrights © 2013 The Korean Society of Radiology Purpose: CT perfusion (CTP) is an important modality in the diagnosis of acute stroke, and the range of its use is gradually expanding from supratentorial to whole brain stroke. We assessed the diagnostic value of multichannel CTP in comparison with conventional CT (CT) in acute pontine infarct. Materials and Methods: CTP and follow-up diffusion weighted magnetic resonance imaging were performed in 74 patients diagnosed with acute pontine infarct among 178 suspicious ones. Diagnostic accuracy of CTP and CT was evaluated and quantitative analysis was performed to define the factors that may influence the detection rate. Results: In the diagnosis of acute pontine infarct, the sensitivity, specificity, and accuracy of CTP was 56.8%, 91.4%, and 77.0% and of conventional CT scan was 47.3%, 93.3%, and 74.2%, respectively. There was no statistically significant difference. Receiver operation characteristic curve revealed both types of imaging to have diagnostic usefulness (p < 0.01) in acute pontine infarct. Among the factors that may affect the detection rate, infarct volume was found to be statistically significant (CTP: p < 0.01, CT: p = 0.01). Conclusion: This is the first study that analyzed the difference between CTP and CT in the diagnostic accuracy of acute pontine infarction. Both CTP and CT are useful diagnostic tools although CTP seems to have a slightly higher detection rate than CT. Index terms Acute Pontine Infarction Multidetector CT Perfusion Conventional CT Diffusion Weighted Magnetic Resonance Imaging Comparison of Diagnostic Usefulness of Multi-Channel CT Perfusion and Conventional Brain CT in the Acute Pontine Infarct 급성 허혈성 교뇌경색에서 다중채널 관류전산화단층촬영과 고식적 전산화단층촬영의 진단적 유용성의 비교

Advances in Contrast-Enhanced Cardiovascular CT for the Evaluation of Myocardial Perfusion

Multidetector CT (MDCT) angiography is a robust method for the accurate diagnosis of coronary artery disease (CAD) in selected patient populations. Recent advances in CT technology have broadened the application of MDCT as a stand-alone imaging modality to identify both CAD and myocardial ischemia in a single examination. Although myocardial perfusion scintigraphy has an extensive evidence base for the diagnosis of myocardial ischemia, MDCT perfusion imaging has several potential advantages including better spatial resolution, which may allow more accurate detection of small areas of ischemia, as well as ability to detect actual rather than relative blood flow, potentially improving diagnostic accuracy for detecting hemodynamically significant multivessel CAD. The purpose of this review is to provide an overview of the evolution of technical and practical aspects related to MDCT perfusion imaging, and to highlight important studies that have assessed the diagnostic accuracy of MDCT stress perfusion imaging, concluding with the emerging role of 320-detector row MDCT.

320-Multidetector row whole-head dynamic subtracted CT angiography and whole-brain CT perfusion before and after carotid artery stenting: Technical note

Introduction Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical potential of recently developed 320-MDCT extending the z-axis coverage to 16 cm in a patient with symptomatic carotid artery stenosis. Methods In a 74-year-old patient presenting with critical symptomatic stenosis of the left CCA, pre- and post-carotid artery stenting whole-head subtracted dynamic MDCT angiography and perfusion were obtained in addition to CT angiography of the supra-aortic trunks. Both whole-head subtracted MDCT angiography and perfusion demonstrated delayed left ICA circulation, which normalized after carotid stenting. Discussion 320-MDCT offers unprecedented z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation. These innovations can consolidate the role of MDCT as a first intention imaging technique for cerebrovascular disorders, in particular for the acute management of stroke.

Observation of hemodynamics after transcatheter arterial chemoembolization of primary hepatocellular carcinoma using multidetector CT perfusion imaging

原发性肝癌发病率呈上升趋势,由于起病隐匿,70%～85%患者就诊时已属中晚期,失去外科手术治疗的机会,肝动脉灌注化疗栓塞术(TACE)通过阻断肝癌血供,导致肿瘤缺血,坏死,控制肿瘤进展、延长患者生存期,为其首选的治疗方法[1-2]。

Dynamic multi-section CT imaging in acute myocardial infarction: preliminary animal experience

To evaluate the feasibility of myocardial first-pass perfusion imaging with multidetector CT (MDCT). In five pigs, myocardial infarction was induced by permanent balloon occlusion of the left anterior descending coronary artery. Dynamic contrast-enhanced MDCT (12x1.5 mm, 120 kV, 30 mAs, 64 acquisitions, 40 ml iopromide 370@4 ml/s) and contrast-enhanced first-pass perfusion magnetic resonance (MR) imaging (TR 7.7 ms/TE 2.6 ms, 64 acquisitions, 0.05 mmol/kg Gd-DTPA) were performed. Finally, the animals were sacrificed, and the heart was excised and stained with triphenyltetrazolin-chloride (TTC). Maximum signal intensity (SImax), contrast material arrival time (CAT), wash-in time (Tmax) and slope were calculated from time-density/signal-intensity curves. The area of myocardial hypoperfusion was measured as the percentage of the left-ventricular area (%LV). Parameters were compared using Bland-Altman plots and Student's t-tests. The hypoperfused area on MDCT was 19.3+/-4.5%LV (MR imaging 17.2+/-4.0%LV). The mean size of infarction was 18.7+/-5.7%LV with TTC. Semiquantitative analysis of MR imaging and MDCT for SImax, Tmax and slope showed significant differences between normal and infarcted myocardium (P<0.05). No significant differences were found for CAT. MDCT and MR imaging both allowed for the differentiation of hypoperfused and normal myocardium. Results given in absolute values differed significantly between both imaging modalities (P<0.05). MDCT has the potential for visual and semiquantitative assessment of first-pass myocardial perfusion.