This assignment will attempt to illustrate the map of medicine followed within the National Health Service for the diagnosis, treatment and follow-up of abdominal aortic aneurysms (AAA). He will discuss the current AAA screening program being implemented across the UK to include the use of ultrasound and computed tomography (CT) as imaging modalities in the demonstration of AAAs. Both the advantages and disadvantages of the modalities used during the diagnosis and treatment of AAA will be shown. Irwin and Rippe (2007, p382) define an aneurysm as; “a segment of the aortic lumen whose diameter exceeds 1.5 times the normal diameter for that segment” and that “the most commonly encountered aortic aneurysm morphology is fusiform.” This may be caused by a mechanical weakening of the muscle fibers in the arterial wall resulting in degenerative changes. High blood flow pressure can cause the arterial wall to protrude or rupture (HealthGuidance, Abdominal Aneurysm, 2011). Due to increased and more dynamic use of ultrasound technology and the increasing age of the population, the prevalence of AAA is also rapidly increasing (Jones, L. 2003). AAAs are currently discovered more frequently as incidental findings during routine examinations (American College of Physicians, 2004). However, with an estimated 6,000 people dying each year in the UK alone as a direct result of AAA, a national screening program is being implemented with the aim of reducing the mortality rate (NHS Screening Programmes. 2011). Ultrasound will be the modality of choice as it has been shown to have 98% accuracy in measurement and sensitivity, (National Institute for Health and Clinical Excellence...... half of paper..... . January 2011] The Vascular Society, Evidence Base [online]Available at: www.aaaqip.com/aaaqip/evidence-base.html[20 January 2011]HealthGuidance, 2011. Abdominal Aneurysm [online]Available at:www.healthguidance. org/.entry/7374/1/Abdominal-Aneurysm---Definition-Causes-Symptoms-and-Treatment.html[25 January 2011]RadiologyInfo, (RSNA and ACR), 2011. Abdominal ultrasound [online]Available at : http://. /www.radiologyinfo.org/en/info.cfm?pg=abdominus[25 January 2011]RadiologyInfo, (RSNA and ACR), 2011. CT Body [online]Available at: http://www .radiologyinfo.org/en/ info.cfm?pg=bodyct[January 25, 2011]American College of Physicians, 2004.Ultrasound Screening for Abdominal Aortic Aneurysm, Patient Summaries [online]Available at: http: //www.annals.org/content/139/. 6/I-56.full[26 January 2011]