Recent reports have shown that these stress distributions have been shown to correlate to the overall geometry of the AAA rather than solely to the maximum diameter. It is also known that wall stress alone does not completely govern failure as an AAA will usually rupture when the wall stress exceeds the wall strength. In light of this, rupture assessment may be more accurate if both the patient-specific wall stress is coupled together with patient-specific wall strength. A noninvasive method of determining patient-dependent wall strength was recently reported, with more traditional approaches to strength determination via tensile testing performed by other researchers in the field. Some of the more recently proposed AAA rupture-risk assessment methods include: AAA wall stress; AAA expansion rate; degree of asymmetry; presence of intraluminal thrombus (ILT); a rupture potential index (RPI); a finite element analysis rupture index (FEARI); biomechanical factors coupled with computer analysis; growth of ILT; geometrical parameters of the AAA; and also a method of determining AAA growth and rupture based on mathematical models.The postoperative mortality for an already ruptured AAA has slowly decreased over several decades but remains higher than 40%. However, if the AAA is surgically repaired before rupture, the postoperative mortality rate is substantially lower, approximately 1-6%. Epidemiology
The occurrence of AAA varies by ethnicity. In the United Kingdom, the rate of AAA in Caucasian men older than 65 years is about 4.7%, while in Asian men it is 0.45%. It is also less common in individuals of African, and Hispanic heritage.
In medicine, an external cause is a reason for the existence of a medical condition which can be associated with a specific object or acute process that was caused by something outside the body. Such causes are classified as "E codes" in ICD 9.External Cause of Injury Codes (E codes) are ICD-9-CM codes or ICD-10 codes that are used to define the mechanism of death or injury, along with the place of occurrence of the event. [1] E codes are assigned on death certificates based on the manner of death. ICD-10 codes in the range V01–X59 refer to unintentional injuries. Codes in the range X60–X84 refer to intentional self-harm. Codes in the range Y85–Y09 refer to assault, and codes in the range Y10–Y34 refer to events of undetermined intent.E codes are well-collected on death certificate data, but less so on hospital discharge data. Numerous initiatives have increased the percentage of records coded (CDC, MMWR March 28, 2008 / Vol. 57 / No. RR-1). == References ==