Post#14 Imaging for suspected or known Abdominal Aortic Aneurysm (AAA)

Limited Ultrasound of the abdomen (76775) is the usual imaging study to follow known AAA.  Screening ultrasound has a different procedure code (76706) and is used only once (see below).  In patients too obese to perform ultrasound, CT abdomen with contrast (74160) may be substituted for screening or known AAA with the same recommended frequency listed below. 

Screening: Medicare regulations allow a one-time screening for AAA in men age 65-75 who have
•    a history of smoking at least 100 cigarettes in his life OR
•    male or female with a family history of AAA
•    Note: as of 2018 guidelines, Medicare policy does not support screening to detect AAA in women without a family history
•    the correct procedure code for this (once only) limited screening ultrasound is 76706

Surveillance:  Once an aneurysm has been diagnosed, follow up imaging (with limited ultrasound (76775) is recommended as follows:
1.    2.6-2.9 cm repeat once at 5 years
2.    3.0-3.4 cm repeat once at 3 years
3.    3.5-4.4 cm repeat annually
4.    4.5-5.4 cm repeat every 6 months
5.    If the aneurysm is greater than 5.4 or the aortic diameter enlarges by .7 cm in 6 months or at least 1 cm in a year may undergo more frequent monitoring AND should see a vascular specialist. 
6.    Patients with known Thoracic Aortic Aneurysm (TAA) may receive one screening abdominal ultrasound for AAA.  Guidelines do not support screening for TAA in patients with known AAA. 

CT or CTA abdomen and pelvis may be approved
•    If surgery is being considered (endovascular or open repair) or
•    If new onset of low back or abdominal pain appears in a patient with a known AAA,.   
•    (See guidelines for additional circumstances related to AAA and post-op follow up). 

Lesson# 14: Ultrasound is the diagnostic imaging study of choice for most cases of abdominal aortic aneurysm.