The segmentation of zones with increased autofluorescence in the junctional zone of parapapillary atrophy

The autofluorescence (AF) derived from the retinal pigment epithelium has the potential to be used as a feature for early glaucoma diagnosis. The aim of this paper is to design and evaluate the method used for semi-automatic segmentation of the zones with increased autofluorescence. A randomized sample of 20 patients (age: 56 ± 10 years) with open angle glaucoma was used. A new method for semi-automatic detection and segmentation of the zones with a higher level of autofluorescence in the junctional zone of parapapillary atrophy has been evaluated. Good agreement has been observed between manually and semi-automatically segmented zones for most of the images, but higher differences may occur for larger hyperfluorescent regions. The data were evaluated using the limits of agreement, with a 2σ border. The described method allows fast and objective evaluation of AF images, preventing undesirable inter-expert variance. A large proportion of AF images could be evaluated successfully by the developed procedure, and the obtained results are comparable to the manual procedure in most cases.