Objective: To study reasonable timing for repeating head ultrasound screenings (HUS) in preterm infants and to find out any change in severity of intraventricular hemorrhage.

Materials and Methods: Medical records and ultrasound findings of all preterm infants younger than 32 weeks gestational age (GA) admitted to the neonatal intensive care unit (NICU) at Phramongkutklao Hospital between January 1, 2014 and December 31, 2018 were reviewed retrospectively.

Results: One hundred thirty-three infants were included in the present study. Eighty-five infants had at least two HUS and included in discrimination analysis. The positive predictive value for having a normal HUS after two previously normal studies seven or more days apart was 89.30% with a specificity of 80%. Of the 24 preterm infants with IVH, 19 had repeated the cranial ultrasound. This revealed that repeating HUS early (day 7 or earlier), 90% (9/10 infants) found no change in finding, whereas repeating HUS at day 30 or later revealed as high as 76.4% change in findings.

Conclusion: Routine screening of cranial ultrasound examinations are recommended for all infants born before 32 weeks GA. If the scan is abnormal, repeating the scan at day 30 or later may be more helpful than as early as day 7. However, if the scan showed no abnormality and had been repeated seven or fewer days apart with the same negative result, subsequent scan may not add benefits. However, these findings need to be proved and may be used only as a guide to design a prospective study in the future.

Keywords: Preterm infant, Screening cranial ultrasound, Intraventricular hemorrhage

DOI: doi.org/10.35755/jmedassocthai.2020.09.11133

Received 12 February 2020 | Revised 5 May 2020 | Accepted 6 May 2020