Study on the intrapulmonary vascular volume in normal preschool children based on computer aided measurement / 中华放射学杂志

ABSTRACT

Objective:To investigate the development of intrapulmonary vascular volume (IPVV) in normal preschool children based on quantitative measurement on chest CT.Methods:The CT data of 407 normal preschool children (236 males and 171 females, aged 1-72 months, with a median of 36 months) who underwent chest CT examination from January 2014 to May 2017 in the "Digital Lung" imaging database were retrospectively collected. The pulmonary vessels were segmented by the "Digital Lung" automatic detection tool, and the IPVV of the whole lung, the right lung, the left lung and each lobe were obtained, and the IPVV upper/lower and IPVV left/right were calculated. According to the age, the subjects were divided into infant period (0-12 months), early childhood period (13-36 months) and preschool period (37-72 months), with 30 cases (17 males and 13 females), 175 cases (95 males and 80 females) and 202 cases (124 males and 78 females) respectively. Spearman correlation analysis was used to evaluate the correlation between IPVV and month age. One-way analysis of variance or Kruskal-Wallis H test was used to compare the differences of IPVV, IPVV upper/lower and IPVV left/right between different months of age. Independent sample t test or Mann-Whitney U test was used to compare the differences of IPVV between different genders, and the normal reference range of IPVV in normal preschool children of different months of age was established. Results:The IPVV of the whole lung, right lung, left lung and each lung lobe were positively correlated with age, the correlation coefficient was 0. 638-0.820 in males and 0. 683-0.791 in females (all P<0.001). There was no significant difference in IPVV of whole lung, right lung, left lung and each lobe between male and female from 0 to 12 months (all P>0.05), but there was significant difference in IPVV of whole lung, right lung, left lung and each lobe between male and female from 13 to 36 months (all P<0.05). There were significant differences in IPVV of the whole lung, right lung, left lung and upper lobe of both lungs between boys and girls from 37 to 72 months (all P<0.05). IPVV upper/lower in the right lung (χ 2=14.00, 12.87, P=0.001, 0.002) and IPVV upper/lower in the left lung (χ 2=6.65, 22.84, P=0.036,<0.001) were significantly different in both boys and girls among 3 months of age. And with the increase of age, it showed a decreasing trend. There was no significant difference in IPVV upper/lower between boys and girls at the same age (all P>0.05).There was no significant difference in IPVV left/right among different months and between different sexes (all P>0.05). Finally, the normal reference value range of IPVV of different genders in infancy, early childhood and preschool age was calculated. Conclusions:The increase of pulmonary vessels in normal preschool children is positively correlated with age. There is no significant difference in IPVV between boys and girls in infant period, but IPVV in boys is larger than that in girls in early childhood period and preschool period. IPVV in the lower lung increased faster than that in the upper lung, but there was no significant difference between the left and right lungs.