BACKGROUND AND PURPOSE: Ultrasonography is increasingly used in vascular research, but there is limited information about the reproducibility of the ultrasound method for screening purposes. In this study the reproducibility of ultrasound assessment of carotid plaque occurrence, thickness, and morphology was examined within the setting of a population health survey. METHODS: In 1994/1995, 6720 participants in the Tromsø Study, Norway, underwent B-mode ultrasound scanning of the right carotid artery. The between- and within-sonographer reproducibility of ultrasound assessment of plaque occurrence and thickness was estimated by repeated scanning of a random sample of 107 participants. The between- and within-sonographer reproducibility of plaque morphology classification (echogenicity, four categories and heterogeneity, two categories) was determined by repeated reading of videotaped images of 119 randomly selected arteries with plaques. RESULTS: Between- and within-sonographer agreement on plaque occurrence was substantial with kappa values (95% CI) of 0.72 (0.60 to 0.84) and 0.76 (0.63 to 0.89), respectively. Reproducibility of plaque thickness measurements was moderate, with mean absolute differences ranging between 0.25 and 0.55 mm (coefficients of variation between 13.8% and 22.4%). Agreement on plaque morphology classification was high, with kappa values ranging between 0.54 and 0.73. CONCLUSIONS: Population screening using B-mode ultrasound provides a valuable means for the detection and morphological evaluation of carotid plaques, whereas measurements of plaque thickness are subject to considerable measurement error.
BACKGROUND AND PURPOSE: Ultrasonography is increasingly used in vascular research, but there is limited information about the reproducibility of the ultrasound method for screening purposes. In this study the reproducibility of ultrasound assessment of carotid plaque occurrence, thickness, and morphology was examined within the setting of a population health survey. METHODS: In 1994/1995, 6720 participants in the Tromsø Study, Norway, underwent B-mode ultrasound scanning of the right carotid artery. The between- and within-sonographer reproducibility of ultrasound assessment of plaque occurrence and thickness was estimated by repeated scanning of a random sample of 107 participants. The between- and within-sonographer reproducibility of plaque morphology classification (echogenicity, four categories and heterogeneity, two categories) was determined by repeated reading of videotaped images of 119 randomly selected arteries with plaques. RESULTS: Between- and within-sonographer agreement on plaque occurrence was substantial with kappa values (95% CI) of 0.72 (0.60 to 0.84) and 0.76 (0.63 to 0.89), respectively. Reproducibility of plaque thickness measurements was moderate, with mean absolute differences ranging between 0.25 and 0.55 mm (coefficients of variation between 13.8% and 22.4%). Agreement on plaque morphology classification was high, with kappa values ranging between 0.54 and 0.73. CONCLUSIONS: Population screening using B-mode ultrasound provides a valuable means for the detection and morphological evaluation of carotid plaques, whereas measurements of plaque thickness are subject to considerable measurement error.
Authors: Rajendra U Acharya; Oliver Faust; A P C Alvin; S Vinitha Sree; Filippo Molinari; Luca Saba; Andrew Nicolaides; Jasjit S Suri Journal: J Med Syst Date: 2011-01-18 Impact factor: 4.460
Authors: Sharon A Lee; Terence C Amis; Karen Byth; George Larcos; Kristina Kairaitis; Tracey D Robinson; John R Wheatley Journal: Sleep Date: 2008-09 Impact factor: 5.849
Authors: Ihsane Hmamouchi; Fadoua Allali; Hamza Khazzani; Loubna Bennani; Leila El Mansouri; Linda Ichchou; Mohammed Cherkaoui; Redouane Abouqal; Najia Hajjaj-Hassouni Journal: BMC Public Health Date: 2009-10-14 Impact factor: 3.295