Prevalence of Suspicious Glaucomatous Optic Nerve in Children aged 6–14 years old – Balsa Nova Eye Study

Abstract

Abstract: : Purpose: To determine the prevalence of suspicious glaucomatous optic nerve (SGON) in a childhood population aged 6–14 years old. Methods: This was a population–based prevalence study of SGON among children from Balsa Nova city, south region of Brazil. All the subjects were evaluated at the city's 11 elementary schools in a screening exam which included: visual acuity determination, Perkins tonometry, retinoscospy, and dilated fundoscopy. All the children that presented an IOP > 21 mmHg and/or SGON were invited to a second exam. During this re–evaluation, children were submitted to a detailed ocular examination with frequency doubling perimetry (FDP), biomicroscopy, Goldmann applanation tonometry, gonioscopy, pachimetry, fundoscopy and corneal diameter / axial length measurements. All the cases that remained classified as SGON were submitted to a third evaluation, 1 to 2 months later, when Goldmann applanation tonometry and FDP were repeated, and optic disc photographs were obtained. The photographs of each case were reviewed by two glaucoma specialists who where masked to the assesments of the other and to the patient's FDP results. Definite SGON was diagnosed only if there were agreement between the two specialists. Reliable FDP exams with two or more misses out of 17 locations were considered as abnormal. Results: A total of 1549 (84,83%) from 1826 children aged 6–14 years old from Balsa Nova city (based on 2000 census data) were evaluated at the screening exam. The children's mean age was 10,01 + 2,38 years; 750 (48,45%) children were females, and there were 1197 (77,31%) white and 303 (19,56%) mixed (black and white). The mean IOP measured by Perkins tonometry was 13.32 + 3.14 mmHg. Thirty two (2.07%) children were selected at the screening evaluation to return and 31 attended all the scheduled visits. According to this study criteria, the prevalence of children with SGON in this population was 0.65% (14 children) (all the stereoscopic photographs will be presented). None of these children presented an IOP above 21 mmHg. Sixty percent (9) of the children with SGON presented two abnormal FDP results (screening C–20–5 and C–20 Full Treshold exams 1 to 2 months appart). None of these children have any known associated systemic disease. Conclusion: It was observed a 0.65% prevalence of children with SGON in this study population aged 6–14 years old. Sixty percent of these SGON children presented two abnormal FDP exams.

Keywords: clinical (human) or epidemiologic studies: prevalence/incidence • optic disc • intraocular pressure