Quickscan: Doppler ultrasound emulation of angiography—its value prior to arteriography in peripheral vascular disease

Abstract

The prevalence of peripheral vascular disease demands a quick, reliable, non-invasive technique for initial assessment. We have devised a new method which combines the two physical principles that (1) Doppler shift is proportional to blood velocity and (2) blood velocity is inversely proportional to arterial cross-section with the ability to track probe position using a non-contacting method. An image of the probe track and any arterial narrowing is shown superimposed on an outline of the patient. Pressure measurement, scan and graphics with final report take about 20 minutes. The accuracy of this system in peripheral vascular disease was evaluated. Thirty-one patients underwent quickscan (QS) and arteriography within an average time of 7 days. Abdominal aorta, common iliac-common femoral, superficial femoral and popliteal artery segments were graded independently as normal, significant stenosis (greater than 50% of diameter) or occluded by both techniques. Of 197 segments, QS correctly assessed 106 normal, 22 stenosed and 28 occluded segments. Four equivocal angiographic stenoses were normal on QS and three severe stenoses were graded occlusion. Fifteen segments on angiography and five on QS were not assessed. For the iliac and superficial femoral artery segments, sensitivity and specificity averaged 77% and 86%, respectively, for all grades. Aortic statistics were invalid (only one significant lesion). Six out of eight popliteal occlusions were correctly diagnosed by QS, but no popliteal stenoses were detected out of six shown on arteriography. Low numbers may contribute to this discrepancy but an improved popliteal scanning method may be necessary. We find initial QS an invaluable aid to direct percutaneous angiography and to indicate potential sites for angioplasty.