Dynamic, Time-Resolved Imaging of Myocardial Perfusion Using 256-Slice Computed Tomography

Runoff computed tomography angiography (CTA) is commonly used to diagnose peripheral artery disease (PAD) of the lower extremities. However, the risk of non-conclusive examination due to suboptimal timing and overrunning the contrast medium bolus is a major pitfall that must be considered. Here we describe two case studies using dynamic time-resolved CTA imaging of the peripheral vascularity.

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Dynamic, Time-Resolved Computed Tomography Angiography Technique to Characterize Aortic Endoleak Type, Inflow and Provide Guidance for Targeted Treatment

Journal of Endovascular Therapy ◽

10.1177/15266028211037986 ◽

2021 ◽

pp. 152660282110379

Author(s):

Marton Berczeli ◽

Alan B. Lumsden ◽

Su Min Chang ◽

Charudatta S. Bavare ◽

Ponraj Chinnadurai

Keyword(s):

Image Guidance ◽

Imaging Techniques ◽

Targeted Treatment ◽

Multiple Time ◽

Type I ◽

Ct Scanner ◽

Time Resolved ◽

Time To Peak ◽

Time Resolved Imaging ◽

Dynamic Time

Purpose: To illustrate dynamic, time-resolved CTA (d-CTA) imaging technique in characterizing aortic endoleak type/inflow using quantitative parameters and its value in providing image guidance for targeted treatment approach. Technique: Dedicated endoleak protocol involved acquiring multiple time-resolved contrast enhanced scans using third-generation CT scanner (Somatom Force®, Siemens Healthineers). Parameters such as scan field of view (FOV), kV, number/timing of scans were customized based on patient’s body-mass-index, timing bolus, and prior imaging findings. D-CTA image datasets were evaluated qualitatively and quantitatively using time-attenuation curves (TAC) analysis after motion correction using a dedicated software ( syngo.via®, Siemens). D-CTA findings from 4 illustrative cases demonstrating type I, type II (inferior mesenteric and lumbar artery inflow), and type III endoleak were illustrated. TAC analysis with time to peak parameter enabled better characterization of endoleak type and inflow. During endoleak intervention, target vessels from d-CTA images were electronically annotated and overlaid on fluoroscopy using 2D−3D image fusion to provide image guidance for targeted treatment. Conclusion: D-CTA imaging with TAC analysis characterizes aortic endoleak type and inflow, in addition to providing image guidance for targeted endoleak treatment. Such dynamic, time-resolved imaging techniques may provide further insights into understanding aortic endoleak that remains an Achilles heel for endovascular aortic aneurysm repair.

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The Potential Value of Hybrid Positron Emission Tomography/Dual-Source Computed Tomography Imaging in Coronary Bypass Surgery

The Heart Surgery Forum ◽

10.1532/hsf98.20111045 ◽

2011 ◽

Vol 14 (5) ◽

pp. 283 ◽

Cited By ~ 2

Author(s):

Andre Plass ◽

Maximilian Y. Emmert ◽

Oliver Gaemperli ◽

Hatem Alkadhi ◽

Philipp Kaufmann ◽

...

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Coronary Artery ◽

Coronary Angiography ◽

Myocardial Perfusion ◽

Predictive Value ◽

Bypass Surgery ◽

Emission Tomography ◽

Positron Emission ◽

Pet Ct

Background: We evaluated how comprehensive assessment of coronary artery lesions and their hemodynamic relevance by means of hybrid positron emission tomography (PET) and computed tomography (CT) imaging would affect decision-making in coronary artery bypass surgery (CABG), compared with using invasive coronary angiography (ICA) alone.Methods: After undergoing ICA, 27 patients (21 men and 6 women; mean SD age, 66 � 10 years) planned for cardiac surgery were scheduled for myocardial perfusion stress/rest evaluation with [13N]ammonia PET and CT coronary angiography. Only ICA was available to the surgeon. Postoperatively, the performed CABG was compared with the hypothetical strategy based on hybrid PET/CT findings (regional coronary flow reserve [CFR], myocardial perfusion defects). Procedures included CABG (n = 18) alone, CABG combined with valve replacement (n = 6), and CABG combined with isolated valve replacement (n = 3). A total of 56 bypass grafts (28 venous and 28 arterial) and 66 distal anastomoses were placed.Results: CT evaluation showed 93% concordance (66/71) with ICA regarding significant stenoses, with sensitivity, specificity, positive predictive value, and negative predictive value of 93.1%, 98.7%, 94.4%, and 98.4%, respectively. In the PET scan, 16 patients had 1 ischemic region, and 12 patients had 1 scar region, including 5 patients who presented with mixed conditions (scar and ischemia). One patient had a completely normal myocardium. Compared with the performed surgery, PET/CT fusion evaluation showed that of the performed anastomoses, 48% had documented ischemia (with a CFR <2 in 86%), 38% were nonischemic (although a CFR value <2 was found in 78%), and 14% had scar tissue (fixed perfusion defect).Conclusions: Although <50% of bypasses were placed to areas with myocardial ischemia, the CFR was low in the majority of nonischemic regions, a finding that may have important prognostic relevance. PET/CT fusion imaging could potentially influence planning for CABG and provide incremental prognostic information.

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Integration Between Computed Tomography and Nuclear Medicine for Non-invasive Assessment of Coronary Anatomy and Myocardial Perfusion

European Cardiology Review ◽

10.15420/ecr.2012.5.2.15 ◽

2009 ◽

Vol 5 (2) ◽

pp. 15

Author(s):

Wanda Acampa ◽

Mario Petretta ◽

Carmela Nappi ◽

Alberto Cuocolo ◽

◽

...

Keyword(s):

Computed Tomography ◽

Coronary Heart Disease ◽

Blood Flow ◽

Heart Disease ◽

Myocardial Perfusion ◽

Myocardial Blood Flow ◽

Imaging Techniques ◽

Emission Computed Tomography ◽

Coronary Anatomy ◽

Non Invasive

Many non-invasive imaging techniques are available for the evaluation of patients with known or suspected coronary heart disease. Among these, computed-tomography-based techniques allow the quantification of coronary atherosclerotic calcium and non-invasive imaging of coronary arteries, whereas nuclear cardiology is the most widely used non-invasive approach for the assessment of myocardial perfusion. The available single-photon-emission computed tomography flow agents are characterised by a cardiac uptake proportional to myocardial blood flow. In addition, different positron emission tomography tracers may be used for the quantitative measurement of myocardial blood flow and coronary flow reserve. Extensive research is being performed in the development of non-invasive coronary angiography and myocardial perfusion imaging using cardiac magnetic resonance. Finally, new multimodality imaging systems have recently been developed bringing together anatomical and functional information. This article provides a description of the available non-invasive imaging techniques in the assessment of coronary anatomy and myocardial perfusion in patients with known or suspected coronary heart disease.

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