Corneal changes in childhood glaucoma.

OBJECTIVE

To study the clinical features and topography of the cornea in eyes with childhood glaucoma.

DESIGN

Cross-sectional, observational study.

PARTICIPANTS

Fifty-eight eyes with childhood glaucoma and 28 eyes of age-matched controls.

METHODS

Clinical and topographic corneal changes were evaluated.

MAIN OUTCOME MEASURES: Corneal topographic changes were evaluated on Orbscan (Orbscan Topography System II; Bausch & Lomb, Salt Lake City, UT) in eyes with childhood glaucoma and those changes were compared with the control eyes.

RESULTS

Fifty-eight eyes with childhood glaucoma and 28 eyes of age-matched controls were evaluated. Thirty-six eyes (62.1%) were classified as having primary childhood glaucoma and 22 eyes (37.94%) as having childhood glaucoma with associated ocular anomalies. The corneas in 18 of 58 eyes (31.0%) with childhood glaucoma were clear, whereas 24.1% of eyes (14/58 eyes) had some corneal opacification. Haab's striae were noted in 44.8% of eyes (26/58 eyes) and were most frequently present between 3 and 5 mm from the optical axis. The mean posterior elevation recorded in eyes with childhood glaucoma controlled with medication or surgery was significantly higher than that in control eyes: 0.043 ± 0.027, 0.042 ± 0.017, and 0.018 ± 0.058 μm, respectively (P < 0.0001). The presence of Haab's striae was correlated significantly with a higher posterior elevation (P = 0.0396) and poor vision. The mean anterior elevation in eyes with childhood glaucoma (0.022 ± 0.015 μm) and in control eyes (0.015 ± 0.078 μm) was comparable (P = 0.08). Corneal astigmatism in eyes with childhood glaucoma was significantly higher and irregular compared with that in control eyes: 2.09 ± 1.40 versus 0.93 ± 0.60 diopter cylinder (P = 0.0001); the irregularity index was 2.8 (range, 1-18.1) and 2.3 (range, 0.6-2.3) at 3 mm (P = 0.0005) and 3.2 (range, 1.4-21.3) and 1.8 (range, 0.5-2.9) at 5 mm, respectively (P = 0.0003). Best-corrected visual acuity correlated significantly with cup-to-disc ratio, axial length, refractive error, astigmatism, and posterior corneal elevation. Multivariate analysis showed a significant correlation only with cup-to-disc ratio and axial length.

CONCLUSIONS

Childhood glaucoma causes a significant increase in posterior corneal elevation and irregular astigmatism, which contribute to visual disability in such eyes.