Role of Multi-slice CT Angiography versus Doppler Ultrasonography in Assessment of Aorto-iliac Arterial Disease

Abstract

The new clinical entity, known as aorta-iliac atherosclerosis obliterans or aorta­ iliac occlusive disease (AIOD), is one of the most frequent clinical problems confronted by vascular surgeons today. The abdominal aorta and iliac arteries- being amongst the arterial segments most commonly affected by atherosclerosis.

Digital subtraction angiography is considered the gold standard technique in assessment of these arteries. The major advantage of DSA are high spatial resolution images and temporal information regarding delayed filling of the vasculature of interest. However, the invasiveness of the procedure, and radiation exposure- led to the need for less and non-invasive imaging techniques.

The aim of this study is to evaluate the MDCT angiography as a recent non invasive technique for investigating aorta-iliac arterial disease as compared to CCD and DSA. This study included 16 patients (12 males & 4 females) with an age range of33- 75 years. All of these patients underwent MDCT angiography and CCD, Only 13 patients underwent DSA.

The arterial tree of the lower limbs was divided into 31 arterial segments. Each segment was evaluated and given a grade from 0 to 4 according to its appearance in the three modalities. There was a 98.7% agreement between the findings of DSA and MDCT angiography. While agreement between DSA and CCD was 96.1%. The sensitivity of MDCT angiography in this study was 98.7% when considering the conventional angiography as the gold standard. while the sensitivity of the color coded Doppler was 96.2%. MDCT angiography has proved to be a less invasive and a reliable method of investigating the lower limb arterial disease with results comparable to DSA. MDCT angiography as a less invasive imaging modality may be used for preoPerative assessment of lower limb arterial disease. Conventional angiography may be spared for patients who are candidate for interventional procedures (e.g. angioplasty or stent application). Color coded Doppler is also a reliable non-invasive method of investigating the lower limb arterial system. It has an advantage over conventional angiography and MDCT angiography that it provides us with data about the velocity of blood distal to the obstruction and shape of the waveform that adds more to determining the hemodynanlic significance of this lesion.

Key Words:

Multi-detector row CT, CT angiography, Aorto-iliac arterial disease, Color. coded Doppler, Non-invasive vascular imaging.