Ultrasound contrast-agent improves imaging of lower limb occlusive disease

Abstract 

Objectives: to evaluate if ultrasound contrast-agent infusion could improve duplex-ultrasound imaging of peripheral arterial disease (PAD) and increase the agreement with digital subtraction arteriography (DSA). Design: prospective and consecutive study. Material: of 60 consecutive PAD patients, 15 were found to have an inconclusive duplex-ultrasound scan of the trifurcation and were included in the study. All 15 patients (53% male) were scheduled for DSA, all being candidates for vascular surgery due to claudication (n = 3, 20%), rest pain (n = 5, 33%) and tissue loss (n = 7, 47%). Methods: on the day before DSA, a duplex-ultrasound scan of the trifurcation was performed. If the duplex-ultrasound scan was found inconclusive, it was repeated during continuous ultrasound contrast-agent infusion. DSA was performed unaware of the duplex-ultrasound results and served as the gold standard. Results: after contrast-agent administration, the number of inconclusively diagnosed segments was significantly reduced by 26 (70%), from 37 to 11(p < 0.001). In 19 segments (73%) contrast-agent infusion changed the diagnosis in accordance with the DSA (p < 0.05). Values of sensitivity and positive predictive value were improved from 0.20 (0.04–0.62) to 0.47 (0.26–0.69) and 0.50 (0.10–0.91) to 0.80 (0.49–0.93), respectively. Specificity and negative predictive value were unchanged. Agreement between duplex-ultrasound and DSA were improved from poor (κ = 0.18 (95% CI: 0–0.82)) to moderate (κ = 0.45 (0.17–0.74)) (p = 0.44). Conclusion: ultrasound contrast-agents improve the diagnostic ability of duplex-ultrasound when scanning difficult arterial segments in patients suffering from PAD.

Eur J Vasc Endovasc Surg 25, 23–28 (2003)

Keywords:  Ultrasonography, Duplex-ultrasound scanning, Doppler, Ultrasound contrast-agent, Levovist®, Peripheral arterial diseases, Vascular surgery, Angiography, Lower limb occlusive disease