IMT was measured with VHRU and HRU in 135 children. Seventeen similar sized porcine arterial specimens were imaged with VHRU and HRU, and the IMT measurements compared to histology.
Adequate imaging was obtained and IMT quantified in all children with 25 and 35?MHz, but the far wall was rarely reached with 55?MHz, even in small children. HRU-IMT was significantly thicker compared with VHRU-IMT in young children (<12 years; HRU: 0.434?¡À?0.040 vs. VHRU: 0.341?¡À?0.054?mm, N?=?66; p?<?0.001). No differences between HRU-IMT and VHRU-IMT were found among older children. No differences were found between far and near wall VHRU-IMT. An increase in porcine arterial IMT with decreasing transducer frequency was observed in comparison to histology. HRU-IMT was significantly overestimated compared with VHRU-IMT and histology-IMT in porcine vessels with an IMT within the pediatric range (0.20-0.50?mm).
VHRU is feasible and more accurate than HRU in quantifying CIMT in young children (<12 years). We recommend using the highest ultrasound transducer frequency applicable to quantify CIMT in the pediatric population.