Abstract 3842: Measurement of Carotid Intima-Media Thickness in Pediatrics: Is Trace or Point to Point Measurement More Reproducible?
Introduction: Ultrasonic measure of carotid intima media thickness (cIMT) is increasingly used in Pediatric research due to an association with CV risk factors in youth. Multiple methods exist to measure cIMT but data on reproducibility of these methods is lacking.
Methods: CIMT measures were obtained on 48 Lean, 31 Obese non-insulin resistant & 43 children with Type 2 Diabetes age 17.1 ± 3.7 years (64% female, 36% male, 21% Caucasian & 79% African-American). 2D ultrasounds were performed on the common carotid, carotid bulb, & internal carotid arteries with a GE Vivid 7 (Milwaukee, Wisconsin). Bilateral point to point (P-P) measurements were made in triplicate on-line at the thickest site of the far wall using the leading edge technique. Digital images were transmitted to a Camtronic Vericis Cardiac workstation for off-line trace method (T) with a pair of multi-point free hand line traces along the thickest interface. Means & standard deviations (SD) with P-P & T methods were calculated & significant difference by method was examined with t-tests. Coefficients of variability (CV), intraclass correlation coefficient (ICC), & Bland/Altman plots were produced to test reproducibility.
Results: The average values were: height (cm) 164.7 ± 11.1; BP (mmHg) 118.4/68.5 ± 13.0/9.8; weight (kg) Lean 69.0 ± 30.1, Obese 87.1 ± 36.1, Type 2 Diabetes 90.1 ± 24.8. CIMT data revealed no significant difference in means between P-P & T method for any carotid segment. The SD & CV were higher & ICC lower for all P-P measures than for T. Bland-Altman plots demonstrated no systematic differences in the variability of measurement.
Conclusion: The newer trace method for cIMT produces values equivalent to the traditional, gold standard of point to point measurement. However, trace method is less variable with better reproducibility. Therefore, trace measurement methodology may be recommended for further cIMT research in the pediatric population.