Normal values of intraocular pressure in full-term Nigerian newborns

To determine the normative range of intraocular pressure (IOP) in full-term newborns and possible association with birth parameters during the first week of life.

This was an observational cross sectional study in which IOP was measured in 1000 eyes of 500 normal full-term newborns using the Perkins applanation tonometer under topical anesthesia. An average of three readings was taken as the IOP value. The relationship between IOP and birth parameters was analyzed.

The male to female ratio was 1:1 with 254 (50.8%) male and 246 (49.2%) female babies. The (mean ± SD) value of IOP in the right eyes was 11.93 ± 1.80 mmHg, ranging between 9.00 and 16 mmHg. In the left eyes, the mean value of IOP was 11.84 ± 1.77 mmHg with a range of 8.00-15.00 mmHg. IOP in males (12.02 ± 1.84 mmHg) was not significantly different from that in females (11.89 ± 1.75 mmHg). There was no significant difference between right and left eyes (p = 0.42). The 95% range (mean ± 2 SD) was 15.53 mmHg for the right eye and 15.38 mmHg for the left. Correlational analysis showed that birth weight and gestational age were positively correlated with IOP.

This study provides useful normative data on IOP among Nigerian full-term newborns. Further studies on possible ethnic/geographic variations of IOP in children may be beneficial.