The main objectives of the original application were as follows: 1) to re-program the Prosound carotid IMT assessment method to utilize more compact hardware; and 2) to test longitudinal transducer positioning with stacking (modified Beach method) of the carotid artery and jugular vein to obtain more reproducible IMT measurements have been completed. Technology for on-line display of baseline and real-time images and a mechanical rotation transducer holding device have been developed. The investigators have reduced IMT measurement variability by 50% (coefficient of variation, CV, from 3.25% to 1.60%) using these newest developments to acquire IMT images. Preliminary data indicate that using the transducer holding device with head in-line anatomical body positioning and lateral scanning, reduces the IMT measurement CV to 0.58%. Additionally, they have developed prototypal software for multiple sequential-frame IMT analysis over full cardiac cycles which further reduces IMT measurement variability. As a continuation of their findings, the investigators propose to develop a carotid artery IMT assessment technique that will be more reproducible than any currently available technique with special application to multicenter image acquisition by: 1) more fully automating IMT image acquisition by developing an electro/mechanical rotational transducer device; and 2) developing an easily deployed automated multiple sequential-frame IMT analysis system. These improvements will effectively maximize IMT measurement reproducibility for a single center and are easily applied to a multicenter clinical setting. A major goal of this continuation application is to deploy their newest and most highly reproducible IMT image acquisition and processing methodology across three clinical sites and determine the cross-sectional and longitudinal variability of this new standardized automated methodology for measuring IMT in a multicenter setting. The investigators state that this methodology has important implications since reduced IMT measurement variability will result in reduced sample size requirements and costs for conducting multicenter studies.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
5R01HL051913-05
Application #
6183440
Study Section
Epidemiology and Disease Control Subcommittee 2 (EDC)
Project Start
1995-08-01
Project End
2001-12-31
Budget Start
2000-08-01
Budget End
2001-12-31
Support Year
5
Fiscal Year
2000
Total Cost
$358,418
Indirect Cost
Name
California Institute of Technology
Department
Type
Schools of Engineering
DUNS #
009584210
City
Pasadena
State
CA
Country
United States
Zip Code
91125