Location: Children's Nutrition Research CenterTitle: Reliability of the echoMRI infant system for water and fat measurements in newborns Author
|Toro-ramos, Tatiana - Columbia University - New York|
|Paley, Charles - Columbia University - New York|
|Wong, William - Children's Nutrition Research Center (CNRC)|
|Pi-sunyer, Xavier - Columbia University - New York|
|Yu, Wen - Columbia University - New York|
|Thornton, John - Columbia University - New York|
|Gallagher, Dympna - Columbia University - New York|
Submitted to: Pediatric Obesity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/25/2017
Publication Date: 7/16/2017
Citation: Toro-Ramos, T., Paley, C., Wong, W.W., Pi-Sunyer, X., Yu, W.W., Thornton, J., Gallagher, D. 2017. Reliability of the echoMRI infant system for water and fat measurements in newborns. Pediatric Obesity. 25(9):1577-1583. http://dx.doi.org/10.1002/oby.21918.
Interpretive Summary: Short-term changes in body fat, body water and muscle mass are difficult to measure among newborns. EchoMRI is a new machine that allows measurements of short-term changes in infants but its accuracy has not been proven. In this study, we compared the body fat and muscle mass measured using the EchoMRI machine and those measured with another proven machine, the PEA POD. We also compared the body water measurements using the EchoMRI machine and compared them to those measured using the proven deuterium dilution method. A total of 42 healthy newborns were studied. The EchoMRI measurements were found to be similar to those measured using the proven methods. Since the new machine does not expose the infants to any radiation and does not require sedation, the new machine is a great tool to monitor short-term changes in body fat, body water, and muscle mass in infants during growth and or under treatment.
Technical Abstract: The precision and accuracy of a quantitative magnetic resonance (EchoMRI Infants) system in newborns were determined. Canola oil and drinking water phantoms (increments of 10 g to 1.9 kg) were scanned four times. Instrument reproducibility was assessed from three scans (within 10 minutes) in 42 healthy term newborns (12-70 hours post birth). Instrument precision was determined from the coefficient of variation (CV) of repeated scans for total water, lean mass, and fat measures for newborns and the mean difference between weight and measurement for phantoms. In newborns, the system accuracy for total body water (TBW) was tested against deuterium dilution (D2O). In phantoms, the repeatability and accuracy of fat and water measurements increased as the weight of oil and water increased. TBW was overestimated in amounts >200 g. In newborns weighing 3.14 kg, fat, lean mass, and TBW were 0.52 kg (16.48%), 2.28 kg, and 2.40 kg, respectively. EchoMRI's reproducibility (CV) was 3.27%, 1.83%, and 1.34% for total body fat, lean mass, and TBW, respectively. EchoMRI-TBW values did not differ from D2O; mean difference, -1.95+/-6.76%, P=0.387; mean bias (limits of agreement), 0.046 kg (20.30 to 0.39 kg). The EchoMRI Infants system's precision and accuracy for total body fat and lean mass are better than established techniques and equivalent to D2O for TBW in phantoms and newborns.