Anterior segment and intraocular pressure measurements of the unanesthetized premature infant.

Thirty-seven premature infants were examined without anesthesia to determine intraocular pressure (I.O.P.) and corneal diameter (C.D.) measurements. The anterior segment of the premature infant was examined and the presence of Bell's phenomenon was recorded. Measurements were done with a Perkin's applanation tonometer, calipers and clear corneal diameter templates. The systolic blood pressure, weight, length and postconceptional age were also recorded. Correlations of these factors were done to determine interdependency of these parameters. The mean values for I.O.P. were 18.04 mmHg for O.D. and 18.62 mmHg for O.S. The mean difference was statistically significant. Mean values for corneal diameters were 8.18 mm O.D. and 8.15 mm O.S. Statistically significant correlations occurred between I.O.P. with C.D. and between C.D. with weight, length and postconceptional age. Techniques for accurate measurement in this age group require particular attention to adequately-sized instrumentation to accommodate small palpebral fissures and corneas.