Color-flow duplex scanning of the leg arteries by use of a new echo-enhancing agent.
OBJECTIVE
This was a dose-finding and effectiveness study of a newly developed contrast-enhancing agent, sulphur hexafluoride (SF(6)), in patients with peripheral arterial disease in whom the therapeutic policy could not be established on the basis of standard color-flow duplex scanning of the leg arteries.


METHODS
In this open-label, randomized, dose-ranging, crossover design, 14 patients in whom the assessment of vessel patency was difficult because of poor visibility (low-flow state) or extensive wall calcifications were studied. Contrast-enhanced duplex scanning was performed on the upper leg (n = 4), lower leg (n = 6), or pedal (n = 4) arteries after intravenous injection of four different dosages of SF(6). The results were compared with those from selective angiography of the vessel of interest. Contrast duration and agreement about the diagnosis and the confidence in the diagnosis were obtained before and after administration of the contrast agent.


RESULTS
No adverse effects of the contrast agent were seen. Overall agreement was reasonable with regard to vessel patency between contrast-enhanced duplex scanning and angiography (71%). Nine of 14 vessels (64%) appeared open when contrast was applied. In four cases this could not be confirmed by angiography; in two of these cases this was due to the presence of collateral vessels. All vessels that appeared occluded with the contrast agent were also occluded on the angiogram. The confidence in the diagnosis increased from 56% to 91% after contrast administration (P <.0001).


CONCLUSIONS
SF(6)-enhanced color-flow duplex scanning is a safe method that may improve the assessment of the patency of leg arteries, particularly in low-flow states. The visualization of collateral vessles during (enhanced) duplex scanning may be misleading because they may be regarded as the vessel of interest.
Ubbink
Dirk Th
DT
Department of Vascular Surgery, Academic Medical Center, Amsterdam, The Netherlands. D.Ubbink@amc.uva.nl
Legemate
Dink A
DA
Llull
Jean-Bernard
JB
D000368:Aged; D000369:Aged, 80 and over; D001157:Arterial Occlusive Diseases / Q000175:diagnosis; D003287:Contrast Media / Q000008:administration & dosage; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D018618:Echocardiography, Doppler, Color; D005260:Female; D005263:Femoral Artery / Q000000981:diagnostic imaging / Q000648:ultrastructure; D006801:Humans; D007089:Image Enhancement; D007866:Leg / Q000098:blood supply* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011150:Popliteal Artery / Q000000981:diagnostic imaging / Q000648:ultrastructure; D011859:Radiography; D012680:Sensitivity and Specificity; D016909:Tibial Arteries / Q000000981:diagnostic imaging / Q000648:ultrastructure; D018616:Ultrasonography, Doppler, Duplex
D003287:Contrast Media