Iso-osmotic bowel preparation improves the accuracy of iliac artery colour flow duplex examination.

Colour flow duplex ultrasonography is currently the non-invasive method of choice for investigating the iliac arteries. However it is only 84-92% sensitive in the best hands when compared with biplanar angiography. Bowel gas and faeces overlying the iliac arteries obscure the vessels and prevent a good ultrasound image. We have previously shown that preparation of the bowel with an iso-osmotic bowel preparation (Klean Prep) improves the clarity of duplex image of the iliac arteries. This is caused by a volume effect which flushes out gas and faeces, leaving a fluid-filled bowel transparent to ultrasound. The aim of this study was to investigate whether this enhanced image increased the diagnostic accuracy of duplex examination. We performed iliac duplex examinations on 56 patients with clinically suspected iliac artery disease, initially with the normal preparation of starving the patients for 12 h and subsequently after preparation by Klean Prep. The results from each investigation were compared with the gold standard of biplanar intra-arterial digital substraction angiography. The use of iso-osmotic bowel preparation (Klean Prep) significantly improved the accuracy of iliac duplex ultrasonography over preparation by 12 h starvation, when compared with biplanar angiography.