The following provides a case study:
- A 69-year-old male presents to the department for a renal ultrasound
- He has elevated PSA levels, nocturia and a reduced stream
- Microscopic hematuria was also detected by his doctor in a urine sample
- He has been instructed to drink one litre of water one hour prior to his appointment and to hold this for the scan
- He appears to be very uncomfortable when you get him from the waiting room and asks you how long the scan will take as he is needing to ‘find the toilet’

Where relevant, in relation to the case study and using correct sonographic terminology, describe an abdominal aortic aneurysm.  Also,  discuss:
- the pathophysiology,
- aetiology, and
- prevalence of the pathology.
- Finally, give your provisional diagnosis and justify why you think this is the case.

 Write your response using less than 500 words.
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