Comments Regarding ‘Assessment of the Accuracy of AortaScan for Detection of Abdominal Aortic Aneurysm (AAA)’

Abstract

The cost of purchasing ultrasound equipment represents a significant financial burden to abdominal aortic aneurysm (AAA) screening programmes. AAA screening programmes use conventional portable ultrasound scanners equipped with colour flow and spectral Doppler modalities. These modalities are not necessary for routine aneurysm screening, adding to the cost of the equipment. Additionally, they could be potentially misleading if used without appropriate training. The introduction of a simple automated handheld device would enable AAA screening to be performed by practice nurses and General Practitioners during a routine health check. This would save a considerable amount of money, making AAA screening cheaper and more cost effective. Patients who are suspected of having an AAA can then be offered a rapid confirmation scan using conventional ultrasound in their local imaging department or vascular unit. In this context, the study by Abbas et al. (comparing the AortaScan device against computed tomography scanning 1 ) is timely and relevant. The reported sensitivity of 81% is clearly not acceptable for it to be used within a national aneurysm screening programme at the present time. However, the results should not be viewed in a completely negative light, as the device was able to detect a significant number of aneurysms. Looking from a positive perspective, the authors provide a useful waypoint for the manufacturer to develop and refine their system until sensitivity is close to 100%. It is only through the publication of unbiased studies that we get a true evaluation of emerging and innovative technologies with the potential to deliver efficiency and savings. What then should be the key performance requirements of an automated device? It should be able to measure aortic diameter to an accuracy of <5 mm, it should be capable of coping with a large burden of thrombus without misidentifying it as aortic wall and it should have the ability to identify aneurysms in the presence of marked vessel tortuousity. The authors also highlight the inability of the device to accurately display the size of aortas measuring less than 3 cm in diameter. This should be a development priority as a screening programme using an automated device could select a diameter threshold below 3 cm for patients to have a conventional ultrasound scan for additional safety. From a technological perspective, the AortaScan represents an example of disruptive innovation where complicated and expensive products are converted into simpler, affordable and more accessible ones.2 With further development, it is possible that the device will become accurate enough to be used in routine practice. This type of disruptive innovation has the potential to replace other types of diagnostic equipment that currently requires specialist operators and for the new simplified technology to be taken out of hospitals and made available in public areas such as pharmacies, supermarkets and communal places. This has the additional advantage of engaging the public with issues of healthcare and health screening in more natural environments, ultimately improving the uptake and accessibility of screening.