Comparison between Computerized tomographic angiography and intraoperative conventional angiography in critical lower limb ischemia

Abstract

By the age of 60, approximately 3–6% of men have intermittent claudication related to lower extremity arterial occlusive disease. About 20% of men and women with intermittent claudication have diabetes (Ehab et al, 2013). Atherosclerosis is the most common form of advanced occlusive disease, surgical treatment or angioplasty is a viable therapeutic strategy(Ehab et al, 2013). Although the history and physical examination often makes the diagnosis of CLI with certainty, for clinical decision making , further diagnostic studies are usually needed. These investigations have a number of purposes: 1. To objectively confirm the diagnosis 2. To localize the responsible arterial lesions and grade their relative severity 3. To assess the need for intervention (by predicting the outcome of conservative management and help in the choice of procedure and if operative intervention be necessary or additional diagnostic studies may be needed. 4. To assess operative risk and operative strategy As with the patient presenting for the first time (Wolfe & porter , 2000). 5. The involvement of other systems with arteriosclerosis needs to be explored. The accurate vascular anatomic mapping of the sites and severity of disease is essential when planning such procedures and this represents the cornerstone in the management of peripheral vascular diseases (Wolfe & porter , 2000). The ‘‘gold standard’’, Digital Subtraction Angiography, is now more often used with therapeutic interventions rather than purely diagnostic studies. Catheter-based angiography is being replaced by computerized tomographic angiography (CTA) and magnetic resonance angiography (MRA) for peripheral vascular diagnostic examinations (Ehab et al, 2013). Computed tomographic (CT) angiography is increasingly used for diagnostic imaging in patients with peripheral arterial disease. The use of multi-detector row technology has resulted in shorter acquisition time, increased volume coverage, lower dose of contrast medium, and improved spatial resolution for assessing small arterial branches (Wolfe & porter, 2000). Our study focuses on the role of multidetedtor CT angiography in the diagnosis of critical limb ischemia in relative to intraoperative conventional angiography and its effect on the decision making. We concluded that multidetector CT angiography of high accuracy in the diagnosis of the arterial lesions and their distribution in the affected artery, with lower accuracy in the infrapopliteal arterial segment than femropopliteal segment. Our study showed underestimation of the occluded lesions in the infrapopliteal segment by CT angiography (occluded lesions diagnosed as multiple stenois). There is a change in the decision making by CT angiography and by conventional angiography intraoperatively, but still not statistically significant except in the lesions in the peroneal artery. Multidetector CT angiography is a valid objective tool in the anatomical diagnosis of the arterial lesions with the critical limb ischemia and subsequent decision and management, but to be taken cautiously in the infrapopliteal segment lesions and when we suspect severe calcification . Also, we still need further studies to compare acuuracy of both multislice CT angiography and conventional angiography.