The following is a summary of “Frequency of Agreement Between Structural and Functional Glaucoma Testing: A Longitudinal Study of 3D OCT and Current Clinical Tests,” published in the May 2024 issue of Ophthalmology by Manik et al.
Researchers conducted a prospective study evaluating the effectiveness of standard glaucoma test and new 3-dimensional (3D) optical coherence tomography (OCT) rim measurement in detecting disease progression during the same check-up.
They studied 124 patients with open-angle glaucoma, randomly selecting per patient with 1 eye with at least 4 yearly visits. Tests included complete dilated eye exams, disc photography (DP), Humphrey visual field (HVF 24-2) testing, 2D OCT retinal nerve fiber layer (RNFL) thickness measurements, and 3D OCT neuroretinal rim measurements (i.e., minimum distance band or MDB). Progression was assessed using event-based analysis, comparing agreement between tests for detecting progression at each visit.
The results showed that in 124 glaucoma eyes, average follow-up lasted for 66.9±16.4 months. Structural tests such as DP, RNFL thickness, and MDB rim thickness progressed in only 5.0% [3/60] and 16.1% [13/81] of eyes. Global MDB rim thickness and global RNFL thickness showed similar agreement with functional HVF testing (16.1% [13/81] and 8.3% [7/84], respectively), and global MDB thickness showed better structure-function agreement with HVF testing than between DP and HVF testing ( i.e. 5.0% [3/60], P=0.04). Moderate glaucoma showed similar or better agreement compared to mild or severe cases.
Investigators concluded that structural and functional tests in glaucoma often don’t show progression together during a clinic visit. Usually, only one or two tests pick up on glaucoma progression.