Noninvasive intracranial pressure measurement in the newborn

A pneumatic applanation tonometer designed for intraocular pressure measurement was modified to measure intracranial pressure (ICP) over the open anterior fontanel in well and sick newborn infants. The device consists of a sensing unit, a pneumatic-to-electric transducer, an amplifier, and a recording unit. Intracranial pressure in the first three days of life in 35 normal term infants was 5.3 +/- 1.3 mm Hg (mean +/- SD) and in 25 normal preterm infants was 5.1 +/- 0.9 mm Hg. Significant elevations in uncomplicated respiratory distress syndrome (6.9 +/- 2.8 mm Hg) and in infants with complicated respiratory distress syndrome (10.1 +/- 3.1 mm Hg). In a group of sick term infants, intracranial pressure measurements were also significantly elevated (14.3 +/- 10.1 mm Hg). This monitor is simple, quick to calibrate and use, capable of reproducible results, and well suited for use in the intensive care unit.