Abstract
PurposeTo develop an expert system for glaucoma screening in a working population based on a human expert procedure using images of optic nerve head (ONH), visual field (frequency doubling technology, FDT) and intraocular pressure (IOP).Methods4167 of 13037 (32%) employees between 40 and 65 years of Evonik Industries were screened. An experienced glaucoma expert (JW) assessed papilla parameters and evaluated all individual screening results. His classification into “no glaucoma”, “possible glaucoma” and “probable glaucoma” was defined as “gold standard”. A screening model was developed which was tested versus the gold-standard. This model took into account the assessment of the ONH. Values and relationships of CDR and IOP and the FDT were considered additionally and a glaucoma score was generated. The structure of the screening model was specified a priori whereas values of the parameters were chosen post-hoc to optimize sensitivity and specificity of the algorithm. Simple screening models based on IOP and / or FDT were investigated for comparison.Results111 persons (2.66%) were classified as glaucoma suspects, thereof 13 (0.31%) as probable and 98 (2.35%) as possible glaucoma suspects by the expert. Re-evaluation by the screening model revealed a sensitivity of 83.8% and a specificity of 99.6% for all glaucoma suspects. The positive predictive value of the model was 80.2%, the negative predictive value 99.6%. Simple screening models showed insufficient diagnostic accuracy.ConclusionAdjustment of ONH and symmetry parameters with respect to excavation and IOP in an expert system produced sufficiently satisfying diagnostic accuracy. This screening model seems to be applicable in such a working population with relatively low age and low glaucoma prevalence. Different experts should validate the model in different populations.
Highlights
Glaucoma is one of the leading causes of visual impairment and blindness worldwide [1]
Re-evaluation by the screening model revealed a sensitivity of 83.8% and a specificity of 99.6% for all glaucoma
Different experts should validate the model in different populations
Summary
Glaucoma is one of the leading causes of visual impairment and blindness worldwide [1]. It is a heterogeneous group of diseases affecting the optic nerve head (ONH). Increased intraocular pressure is a main risk factor for glaucoma. Individuals with high intraocular pressure (IOP) may develop glaucoma with ONH damage and visual field defects (glaucoma cases). Thresholds may be heterogeneous across a population of individuals above which IOP may cause damage. There are subjects with high IOP and no glaucoma (ocular hypertension cases) on the one hand, and patients with normal IOP and severe ONH damage (normal tension glaucoma cases) on the other hand [2,3]
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have