Optimal cost-effective timing of cranial ultrasound screening in low-birth-weight infants.

Our aim in this study was to determine whether delaying the initial screening cranial ultrasound on infants of low birth weight until the 2nd week of life affects clinical diagnosis and cost of patient care. Data were reviewed on all premature infants of less than 33 weeks gestation or less than 1500 g birth weight admitted to the Neonatal Intensive Care Unit between January 1989 and August 1992. Babies admitted before August 1991 were screened on day 4 or 5 with a second scan frequently performed on day 14; babies admitted after that date were screened once between days 10-14. Populations were compared for (1) proportion of ultrasound findings considered normal on final diagnosis; (2) incidence of major and minor abnormalities; (3) periventricular leukomalacia (PVL); (4) change in diagnosis from 1st to 2nd week; and (5) number of studies performed per patient. The study group was composed of 499 eligible infants. Demographic features of infants screened in the 1st vs. 2nd week of life were similar, with comparable diagnoses of major and minor intracranial hemorrhage and ventricular dilatation; however, more patients screened in the 1st week had questionable PVL diagnosed (p = 0.04). There was a significant decrease in the number of scans per patient in the group screened in the 2nd week (p < 0.004). Routine screening may be delayed until the 2nd week without compromising patient care. Widespread use of a similar screening protocol would result in significantly fewer studies being performed, with an estimated saving, in the USA, of more than $3 million annually.