Ultrasonic Backscatter Technique for Assessing and Monitoring Neonatal Cancellous Bone Status in Vivo

Metabolic bone disease (MBD) impacts the prognosis of premature infants. There is an urgent need for a portable, noninvasive, and radiation-free method for assessing neonatal bone status. The objective of this study is to evaluate the feasibility of the ultrasonic backscatter technique for assessing and monitoring cancellous bone status in neonates. Ultrasonic backscatter measurements were performed on 766 infants at birth and followed up weekly during hospitalization, utilizing transducers with central frequencies of 3.5 MHz and 5.0 MHz. Backscatter parameters, including apparent integrated backscatter (AIB), frequency intercept of apparent backscatter (FIAB), and frequency slope of apparent backscatter (FSAB) were calculated. Correlations were analyzed with both anthropometric and biochemical indices. We found that AIB (|r| = 0.40-0.47, p <; 0.001), FIAB (|r| = 0.36-0.45, p <; 0.001), and FSAB (|r| = 0.10-0.25, p <; 0.01) were significantly correlated with gestational age, weight, length, and head circumference at birth at both the 3.5 MHz and 5.0 MHz frequencies. Backscatter parameters showed regular changes at different postnatal age and correlations with anthropometric indices persisted during the first month of life. Significant differences were also found in subgroup analyses based on gestational age, birth weight, gender, multiple births, and intrauterine growth. AIB and FIAB were shown to be more effective than FSAB. This study suggests the ultrasonic backscatter technique is feasible for neonatal cancellous bone status evaluation at birth and for dynamic monitoring.