Glaucoma is a progressive, neurodegenerative disease that is increasing in prevalence worldwide. There is a need to develop ways in which to diagnose the disease sooner and more reliably in order to prevent irreversible visual loss and meet the growing demands on healthcare services. Research into neuroprotective therapies in glaucoma is lacking a reliable surrogate marker in order to show treatment efficacy in a meaningful and cost-effective manner. The detection of apoptosing retinal cells (DARC) is a new technique that has promise in providing a solution to this unmet clinical need. Multiple animal studies have demonstrated its use as a biomarker in quantifying the effect of retinal neuroprotection methods, and it has recently been translated into humans in phase I and II trials, with phase I demonstrating the visualisation of individual apoptosing retinal cells in healthy and glaucomatous patients, with good safety and tolerability. The future for this technique will now be identifying disease-specific characteristics of human disease that can be used in order to provide us with a much-needed surrogate marker in the field of retinal neurodegeneration.