Volumetric Analysis of Gallbladder in Extremely Premature Infants

BACKGROUND: We hypothesized that gallbladder (GB) volume is affected by serial changes during the early infancy period in extremely premature infants. METHODS: We conducted a prospective study of extremely premature infants admitted to the neonatal intensive care unit of Fukushima Medical University Hospital, Fukushima City, Japan between January 2014 and December 2015. GB volume was measured by an abdominal ultrasound ellipsoid method between Day 0 and Day 56 after birth within 60 minutes before enteral feeding. We calculated GB volume (mL)/weight (kg), which was evaluated as GV/W. RESULTS: Intotal, 30 infants were included. Themediangestationalageoftheinfantswas 26 weeks 5 days (range, 23 weeks 1 day–28 weeks 6 days), and the median birth weight was 731 g (range, 398–1220 g). The detection rate of GB decreased in the infants over time; the rates were > 93% between Day 0 and Day 7 and < 77% between Day 10 and Day 56 after birth. GV/W decreased in the infants over time. The median GV/W values were 0.18 (range, 0.05 –0.59) in infants on admission and constantly < 0.05 in those between Day 10 and Day 56 after birth. There was no correlation of GV/W with clinical variables after birth. CONCLUSION: It is considered that GB volume is not affected by serial changes without nonfavor-able course of enteral nutrition.