The progression of thrombus in an ex-vivo shunt model evaluated by intravascular ultrasound radiofrequency analysis.
Ultrasound Med Biol
; 25(4): 561-6, 1999 May.
Article
in En
| MEDLINE
| ID: mdl-10386731
ABSTRACT
We tested the ability of ultrasound radiofrequency (RF) signal analysis to characterize thrombus accumulation in a Dacron graft incorporated into the exteriorized arteriovenous shunt in 3 baboons with constant blood flow for 60 min. Thrombus formation was quantified by sequential measurements of 111Indium-labeled platelet deposition. RF signals were acquired every 15 min at 2 sites in the graft, using a 2.9 Fr intravascular ultrasound catheter-based transducer (30 MHz) and digitized at 250 MHz in 8-bit resolution. Regions of interest were placed within a 0.5-mm perimeter adjacent to the graft wall. Integrated backscatter increased significantly (p < 0.001) with increasing platelet deposition. However, mean-to-standard deviation ratio of the RF envelope showed no significant change and the distribution pattern of the RF probability function remained constant and consistent with a Rayleigh scattering process. These results provide a basis for using RF analysis to monitor the time-course of thrombus formation.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Thrombosis
/
Ultrasonography, Interventional
/
Disease Models, Animal
Type of study:
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Ultrasound Med Biol
Year:
1999
Document type:
Article
Affiliation country:
United States