With so many diagnostic tools in today’s optometric practice, it can be a challenge to know which is ideal for a certain patient population. A new study recently published in the British Journal of Ophthalmology might shed some light on the issue, at least for vertical cup to disc ratio (VCDR) measurements.1

Researchers in China measured the VCDR in 140 eyes of 75 patients with ocular hypertension using optical coherence tomography (OCT), Heidelberg retina tomography (HRT) and stereophotography of the optic nerve head (ONH) in patients with ocular hypertension (OHT). They then calculated the patients’ corresponding estimated five-year risk for development of glaucoma based on each measurement. While the differences they found weren’t substantial, they do highlight variability worth noting.1

The VCDR OCT measurements revealed a five-year risk of 19.54%, compared with an 18.13% risk based on HRT data. Stereophotography of ONH with two specialists provided the lowest five-year risk of glaucoma at 16.70%.1

“The study highlights the disagreement among the different parameters of measuring ocular hypertension, which in turn impacts the estimation of 5-year risk of glaucoma development,” according to a Practice Update commentary.2

1. Chan PPM, Chiu VSM, Wong MOI. Variability of vertical cup to disc ratio measurement and the effects of glaucoma 5-year risk estimation in untreated ocular hypertensive eyes. Br J Ophthalmol. June 1, 2018. [Epub ahead of print].
2. Variability of vertical cup to disc ratio measurement and the effects of glaucoma 5-year risk estimation in untreated ocular hypertensive eyes. Practice Update. June 26, 2018.