CT Angiography in the Lower Extremity Peripheral Artery Disease Feasibility of an Ultra-Low Volume Contrast Media Protocol

Barbora Horehledova,Nienke G Eijsvoogel,Babs M F Hendriks,Gianluca Milanese,Casper Mihl,Rutger Brans,Joachim E Wildberger,Marco Das

doi:10.1007/s00270-018-1979-z

Barbora Horehledova, Nienke G Eijsvoogel + Show 6 more

Open Access

https://doi.org/10.1007/s00270-018-1979-z

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Abstract

PurposeThe ALARA principle is not only relevant for effective dose (ED) reduction, but also applicable for contrast media (CM) management. Therefore, the aim was to evaluate the feasibility of an ultra-low CM protocol in the assessment of peripheral artery disease (PAD).Materials and methodsFifty PAD patients were scanned on third-generation dual-source computed tomography, from diaphragm to the forefoot, as follows: tube voltage: 70 kV, reference effective tube current: 90 mAs, collimation: 192 × 2 × 0.6 mm, with individualized acquisition timing. The protocol ED (mSv) was quantified with dedicated software. CM protocol consisted of 15 ml test bolus and 30 ml main bolus (300 mgI/ml) injected at 5 ml/s, followed by a 40 ml saline chaser at the same flow rate. Aorto-popliteal bolus transit time was used to calculate the overall acquisition time and delay. Objective (hounsfield units—HU; contrast-to-noise ratio—CNR) and subjective image quality (four-point Likert score) were assessed at different anatomical regions from the aorta down to the forefoot.ResultsMean attenuation values were exceeding 250 HU from aorta down to the anterior tibial artery with CNR < 13. However, decline in attenuation was observed in more distal region with mean values of 165 and 199 HU, in left and right dorsalis pedis artery, respectively. Mode subjective image quality from the level of aorta down to the popliteal segment was excellent; below the knee mode score was good. The mean ED per protocol was 1.1 ± 0.5 mSv.ConclusionUse of an ultra-low CM volume protocol at 70 kV is feasible in the evaluation of PAD, resulting in good to excellent image quality with mean ED of 1.1 ± 0.5 mSv.Level of evidenceLevel 3, Local non-random sample

Highlights

Peripheral arterial disease (PAD) is a slowly developing gradual narrowing of the vascular lumen caused by atherosclerosis, which is thereby limiting the blood flow in the affected area
Decline in attenuation was observed in more distal region with mean values of 165 and 199 HU, in left and right dorsalis pedis artery, respectively
Use of an ultra-low contrast media (CM) volume protocol at 70 kV is feasible in the evaluation of peripheral artery disease (PAD), resulting in good to excellent image quality with mean effective dose (ED) of 1.1 ± 0.5 mSv

Summary

Introduction

Peripheral arterial disease (PAD) is a slowly developing gradual narrowing of the vascular lumen caused by atherosclerosis, which is thereby limiting the blood flow in the affected area. The diagnostic value of CTA largely depends on the degree of intravascular contrast enhancement within the arterial segment of interest [6]. Previous studies showed that large CM volumes of up to 150 ml, accompanied by relatively high radiation doses, were used to overcome these difficulties [3, 4]. This is not in accordance with the ‘‘As Low As Reasonably Achievable’’ (ALARA) safety principle, which is relevant for dose reduction, and applicable for CM management

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