Early diagnosis of acute intracranial hypertension is essential for the optimal treatment. Opthalmic ultrasound measurement of optic nerve sheath diameter (ONSD) is an easy, portabl, noninvasive and a radiation free technique to determine increased intracranial pressure.
The aim was to establish the normal values for ONSD in premature and mature newborns.
Newborns without intracranial pathology in NICUs and Obstetrics/ Gynecology Departments were included. ONSD were measured at a distance 2, 2.5 and 3 mm beyond the right optic nerve head in preterms and at 3 mm in term infants. Measurements were done by a pediatric intensive care fellow who expertise with point-of-care ultrasound.
554 newborn infants (premature:253, mature:301) were included in the study. The mean ONSD of premature babies from 2, 2.5 and 3 mm were 0.32±0.03 cm (range 0.20-0.42 cm), 0.33±0.03 cm (range 0.22-0.45 cm) and 0.36±0.02 cm (range 0.29-0.45 cm), respectively. The mean ONSD from 3 mm behind the optic disc of mature babies was 0.40±0.027 cm (range 0.33-0.36 cm). There was no significant difference in ONSD between males and females. In the correlation analysis, a significant, strong and positive correlation was found between ONSD measurements from 2, 2.5 and 3 mm behind the optic disc and gestational age, actual weight, birth height and birth head circumference.
Our study is important in terms of being the largest series in the literatu defining the normal range of ONSD in newborns. The normal values reported by present study may be used for evaluating the ONSD of newborns with and without increased incracranial pressure.