Reliability of the measurement of the abdominal aortic diameter by novice operators using a pocket-sized ultrasound system

Abstract

Background: Despite favorable results of randomized studies and several guidelines, screening for abdominal aortic aneurysm is poorly implemented in most countries. In order to implement an effective abdominal aortic aneurysm screening programme, training of physicians other than cardiovascular imaging specialists is necessary. Also, the use of pocket-sized ultrasound systems seems an appealing alternative to conventional echography machines for large-scale screening.

Aims: To test the hypothesis that, after a short period of specific training with a pocket-sized ultrasound system, novice operators could reliably measure the abdominal aortic diameter. We assessed the agreement between abdominal aortic diameter measurements from novice operators using a pocket-sized ultrasound system and experts using conventional machines.

Methods: After focused training of novice operators, the abdominal aortic diameter was independently measured at least four times: by two experts using conventional ultrasound, by one expert using a pocket-sized ultrasound system and by at least one novice operator using the pocket-sized system; each operator was blinded to the others.

Results: The aortic diameters of 56 patients were measured. The intraclass correlation coefficients between the four sets of measurement were all>0.91 and the mean difference between the measurements was negligible (<1mm). The interoperator variability for experts using conventional machines versus novices using pocket-sized machines was ≤ 4mm in 92.0% of cases. No learning curve over time was noted.

Conclusion: In order to screen for abdominal aortic aneurysm, the abdominal aortic diameter can be accurately measured by non-specialist physicians with pocket-sized ultrasound devices after a short period of training.

Keywords: AAA; Abdominal aortic aneurysm; Anévrysme de l’aorte abdominale; CI; Dépistage; Experience; Expérience; Fiabilité; ICC; NHS; National Health Service; Reliability; Screening; Ultrasound; abdominal aortic aneurysm; confidence interval; intraclass correlation coefficient; Échographe de poche.