Evolution of central corneal thickness in children with congenital glaucoma requiring glaucoma surgery

Background The purpose of the study was to investigate the evolution of central corneal thickness (CCT) in correlation to the intraocular pressure (IOP) in children with congenital glaucoma before and after glaucoma surgery. Methods Nine eyes of five children (age 2 weeks to 6 months, mean 23 weeks) underwent trabeculotomy for congenital glaucoma. Corneal ultrasound pachymetry (PacScan 3000 AP, Technomed, Germany), tonometry using the Perkins tonometer, and slit-lamp examination (additionally to a clinical routine examination with retinoscopy, funduscopy, measurement of axial length and corneal diameter) were performed before and for at least 12 months after glaucoma surgery. In all children, corneal pachymetry and slit-lamp biomicroscopy—and whenever possible applanation tonometry—were performed without sedation or general anesthesia. If measurement of the IOP was not possible otherwise (in four of the five children), sedation with midazolam orally was used to measure the IOP at 2 weeks, 6 weeks, and 3 months after trabeculotomy, then every 3 months. Results Six of nine eyes had biomicroscopically clear corneas without visible corneal edema before trabeculotomy. In three eyes, a corneal edema was visible in at least one quadrant of the cornea. Regarding all eyes together, mean CCT was 651 ± 138 μm before trabeculotomy; this decreased to 592 ± 119 μm within 2 weeks after trabeculotomy. At 6 weeks and 3 months there was a further regression to 569.4 ± 16 μm. Mean IOP was 18.6 ± 7.5 mmHg before and decreased to 14.8 ± 5.8 mmHg after glaucoma surgery. Regarding IOP data obtained under general anaesthesia, decrease of CCT was significantly correlated with decrease in IOP. There was no significant difference in the correlation between eyes with and without visible corneal edema. Conclusions Corneal ultrasound pachymetry appears to be a valuable additional measure in the follow-up of infants and small children requiring glaucoma surgery. Financial interest: None Oral presentation at the annual meeting of the DOG (German Ophthalmological Society), Berlin, September 2006