Diagnostic Imaging of Peripheral Arterial Disease with Multi-Detector Row Computed Tomography Angiography

Peripheral arterial disease (PAD) is in the majority of patients caused by atherosclerosis in the lower extremities distal to the aortic bifurcation. Atherosclerosis is a complex systemic, progressive and degenerative disease of the intima of the arterial wall, which affects both large and medium-sized arteries. The prevalence of symptomatic PAD is 3-5% in older adults in different Western populations (1-2). Atherosclerosis has a pre-clinical course with absence of clinical symptoms for several decades. PAD generally becomes evident with symptoms of intermittent claudication. Intermittent claudication is defined as muscle cramps in the lower limb that occur following exercise and are relieved with rest. In a minority (a quarter) of patients, the disease progresses to critical limb ischemia i.e. rest pain or tissue necrosis (3-5). The diagnosis of PAD is based on patient history and physical examination. The severity of PAD is generally classified by measuring the ankle-brachial indices

Living renal donors: optimizing the imaging strategy--decision- and cost-effectiveness analysis

PURPOSE: To determine the most cost-effective strategy for preoperative imaging performed in potential living renal donors. MATERIALS AND METHODS: In a decision-analytic model, the societal cost-effectiveness of digital subtraction angiography (DSA), gadolinium-enhanced magnetic resonance (MR) angiography, contrast material-enhanced spiral computed tomographic (CT) angiography, and combinations of these imaging techniques was evaluated. Outcome measures included lifetime cost, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios. A base-case analysis was performed with a 40-year-old female donor and a 40-year-old female recipient. RESULTS: For the donor, MR angiography (24.05 QALYs and 9,000 dollars) dominated all strategies except for MR angiography with CT angiography, which had an incremental ratio of 245,000 dollars per QALY. For the recipient, DSA and DSA with MR angiography yielded similar results (10.46 QALYs and 179,000 dollars) and dominated all other strategies. When results for donor and recipient were combined, DSA dominated all other strategies (34.51 QALYs and 188,000 dollars). If DSA was associated with a 99% specificity or less for detection of renal disease, MR angiography with CT angiography was superior (34.47 QALYs and 190,000 dollars). CONCLUSION: For preoperative imaging in a potential renal donor, DSA is the most cost-effective strategy if it has a specificity greater than 99% for detection of renal disease; otherwise, MR angiography with CT angiography is the most cost-effective strategy