Optic Neuropathy Probability Calculator

The predictive model uses axial length, age, intraocular pressure (IOP), and other clinical factors to estimate the likelihood of developing glaucomatous and nonglaucomatous nerve damage. 

The study, published in the British Journal of Ophthalmology, analysed data from 17,996 participants (35,167 eyes) enrolled in five population-based studies that included children, adults, and older adults.1  

Participants underwent comprehensive ophthalmic examinations that included refraction, ocular biometry, optic nerve and macular photography and, in most cohorts, optical coherence tomography (OCT) imaging. Adult participants also completed visual field testing. 

The researchers – from France, Germany, India and China – focused on glaucomatous or glaucoma-like optic neuropathy (GLON) and nonglaucomatous optic neuropathy (NGON). The authors also accounted for eyes that exhibited features of both conditions. 

The researchers randomly split the study population into development and validation groups to build and test predictive equations.  

The authors emphasised that the equations should be viewed as approximate estimates that may give ‘some hints’ of the future probabilities of GLON and NGON in highly myopic eyes

Axial length and age emerged as particularly influential risk factors. Using the equations, a non-Indian patient with an axial length of 28 mm and an IOP of 22 mmHg had an estimated GLON probability of 3.5% at age 30, rising to 60.2% by age 75, with the estimated NGON probability also increasing from 3.4% to 16.4% over the same period. In another example, an eye with a 30 mm axial length experienced an estimated rise in GLON risk “from 6.9% to 75.6%”, while its NGON risk increased “from 28.2% to 68.4% from age 30 to 75 years”. 

The authors emphasised that the equations should be viewed as approximate estimates that may give “some hints” of the future probabilities of GLON and NGON in highly myopic eyes.