Abstract
Purpose: :
To determine the central corneal thickness (CCT) with different devices and the intraocular pressure (IOP) in moderately to late preterm (MLP) children at 8 years of age.
Methods: :
84 eyes of 42 MLP children (20 girls, 22 boys) at a mean age of 7.97 years (range 7.20-8.63) were studied. Measurements of CCT and IOP was carried out on 12 small for gestational age (SGA) children (7 boys, 5 girls; mean gestational age (GA) 34 ± 2 weeks; mean birth weight 1843 ± 402 gram) and on 30 born appropriate for gestational age (AGA) children (15 boys, 15 girls; mean GA35 ± 2 weeks; mean birth weight 2413 ± 377 gram). CCT was determined with the use of both an ultrasound pachymeter and Optical Coherence Tomography (OCT) Imaging (3D-OCT-1000 Topcon, Inc., Tokyo, Japan). IOP was determined with I-care tonometer. Both right and left eye values were used since there was no statistically significant difference between them.
Results: :
The mean CCT using OCT was 552 ± 28 µm in the SGA children (n=24) and 556 ± 25 µm in the AGA children (n=49); p=0.59. The CCT using ultrasound pachymeter was 597 ± 47 µm in the SGA children (n=20) and 561 ± 27 µm in the AGA children (n=53); p=0.05. Measurements by the ultrasound pachymeter showed a statistically significant difference between the two groups in the left eyes (p= 0.04), but not in the right eyes (p=0.06). When comparing CCT measured by ultrasound pachymeter and OCT, the mean value was 571 ± 37 µm (n=73) and 555 ± 26 (n=73), respectively (p<0.0001). Mean IOP was 16.0 ± 2.7 mm Hg (n=84).There was no difference between either mean IOP in SGA (16.8 ± 3.8 mm Hg; n=24) and AGA (16.8 ± 3.8 mm Hg; n=60) children or the right and left IOP measures between the groups. No difference in the IOP measurements in relation to the CCT was found.
Conclusions: :
Our results in this study show no difference in CCT or IOP measurements in MLP children when comparing those who were born SGA with AGA, although a tendency towards a thicker CCT in SGA children using ultrasound pachymeter existed. In addition, a difference in the CCT measured with OCT and ultrasound pachymeter was found. Ultrasound Pachymetry seems to overestimate the CCT, especially in SGA children, in comparison to the OCT CCT measurements although further studies are needed to demonstrate the interchangeability and accuracy of these devices.
Keywords: cornea: clinical science • intraocular pressure • clinical (human) or epidemiologic studies: systems/equipment/techniques