An international team of researchers recently used a custom fundus camera and optical coherence tomography (OCT) to discover mitochondrial dysfunction in eyes with ocular hypertension (OHT), even before signs of glaucoma.

The study, published in the Journal of Glaucoma, looked at 38 eyes with primary open-angle glaucoma (POAG), 16 eyes with OHT and 32 controls using a fundus camera modified to measure full retinal thickness fluorescence to detect flavoprotein fluorescence (FPF), an indicator of mitochondrial activity. They used OCT to measure the retinal ganglion cell-plus layer (RGC+) thickness and then calculated the ratio of macular FPF to RGC+ thickness as a primary outcome.

The researchers found both macular FPF and the macular FPF/RGC+ thickness ratio were significantly increased in OHT compared with control eyes. Although macular FPF was not significantly increased in POAG eyes compared with controls, the macular FPF/RGC+ thickness ratio was.

Even without evidence of glaucomatous damage, “OHT eyes displayed significantly elevated macular FPF, suggesting that mitochondrial dysfunction may be detected before structural changes visible on current clinical imaging,” the researchers said. “Our preliminary results suggest that macular FPF analysis may prove to be a useful tool in assessing and evaluating OHT and POAG eyes.”