Abstract
Purpose: :
To determine the specificity of the Heidelberg Retina Tomography automated shape analysis tool (ASAT) in a normal elderly population.
Methods: :
6540 eyes of 3470 normal subjects (defined with fields and IOP) with a mean age 74 years, range 63 -99 years, from The Bridlington Eye Assessment Project (BEAP) were selected. Patients underwent optic nerve imaging using HRT 2 as well as a standard ophthalmic examination by trained optometrists. Scan data was imported into HRT3 for calculation of Moorfields Regression Analysis 3 (MRA3) and Glaucoma Probability Score (GPS), the internal ASAT. Subjects with a HRT mean pixel height standard deviation of greater than 68 um were excluded from the analysis.
Results: :
When borderline cases were classified as abnormal, the specificities of GPS, Moorfields Regression Analysis 3 (MRA 3) and Clinical evaluation were 77 %, 83% and 94% respectively. This rose to 83% and 92 % for GPS and MRA when borderline cases were re-classified as normal.
Conclusions: :
When used in isolation, GPS is less specific than MRA3 or fundoscopy by trained optometrists when screening a population of normal elderly individuals.
Keywords: imaging/image analysis: clinical • optic nerve