title: Ultrasound contrast-agent improves imaging of lower limb occlusive disease.
abstract: OBJECTIVE
  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).
  
  
  METHODS
  prospective and consecutive study.
  
  
  METHODS
  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 (kappa = 0.18 (95% CI: 0-0.82)) to moderate (kappa = 0.45 (0.17-0.74)) (p = 0.44).
  
  
  CONCLUSIONS
  ultrasound contrast-agents improve the diagnostic ability of duplex-ultrasound when scanning difficult arterial segments in patients suffering from PAD.
authors.affiliation: Department of Vascular Surgery, Rigshospitalet, Copenhagen, Denmark.
authors.forename: J P
authors.initials: JP
authors.lastname: Eiberg
authors.forename: M A
authors.initials: MA
authors.lastname: Hansen
authors.forename: F
authors.initials: F
authors.lastname: Jensen
authors.forename: J B Grønvall
authors.initials: JB
authors.lastname: Rasmussen
authors.forename: T V
authors.initials: TV
authors.lastname: Schroeder
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015901:Angiography, Digital Subtraction; D001157:Arterial Occlusive Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D006801:Humans; D035002:Lower Extremity / Q000098:blood supply; D008297:Male; D008875:Middle Aged; D016491:Peripheral Vascular Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D011134:Polysaccharides; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016909:Tibial Arteries / Q000000981:diagnostic imaging*; D018615:Ultrasonography, Doppler, Color
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508