Review of the assessment of single level and multilevel arterial occlusivedisease in lower limbs by duplex ultrasound

The purpose of this article is to review the performance of duplex ultrasou nd scanning in assessing lower limb arterial disease with emphasis on patie nts with multisegmental occlusive lesions. Several studies have reported th at duplex scanning can be as accurate as angiography to localize arterial s tenoses, In spite of these promising results, there still remain some diffi culties and controversies. Among them, it has been reported that multisegme ntal disease may affect the accuracy of duplex scanning. Indeed, some studi es have indicated a lower sensitivity for detecting significant stenoses di stal to severe or total occlusions. It also was demonstrated that second-or der stenoses were detected with lower sensitivity compared to first-order s tenoses, The main reason proposed to explain this lower sensitivity is that the highly reduced flow distal to occluded or highly stenotic segments inc reases the difficulty of detecting significant Doppler velocity changes in the distal or secondary stenoses, The intrinsic limitations of the peak sys tolic velocity ratio used as a classification criterion are presented. Fina lly, new and promising developments in power Doppler imaging and ultrasound contrast agents are discussed, because they may allow expansion of the cap abilities of current ultrasound scanning systems and provide more accurate diagnosis of patients with multiple disease, (C) 1999 World Federation for Ultrasound in Medicine & Biology.