Optic Nerve Head Measurements Across Optical Coherence Tomography Platforms and Incidental Optic Nerve Head Drusen in Community Screenings

ABSTRACT Background Automated vertical cup‐to‐disc ratio (VCDR) measurements are commonly used in optic nerve assessment, but measurements may vary across optical coherence tomography (OCT) platforms, particularly in eyes with atypical optic nerve anatomy such as optic nerve head drusen (ONHD). Purpose This study aimed to assess variability in automated VCDR measurements across three OCT devices in a community screening setting, including eyes with normal optic nerve heads (ONH), ONHD, and screen‐positive cases. Method Data from screenings conducted between January 2024 and January 2025 were analyzed. Participants underwent visual acuity testing, intraocular pressure measurement, and nonmydriatic 3D wide‐scan OCT imaging, using one of three devices: Topcon Maestro‐1, Topcon Maestro‐2, or Canon Xephilio OCT‐R1. Eyes were categorized as control, ONHD, or screen‐positive. VCDR values were summarized by device. In ONHD eyes, one‐sample testing compared measured VCDR against the expected anatomic value of zero. Results ONHD detection rate was 16.96%. In controls, mean VCDR was 0.58 (Canon Xephilio OCT‐R1), 0.55 (Maestro‐1), and 0.62 (Maestro‐2). Among 17 paired control eyes, VCDR did not significantly differ between Canon Xephilio OCT‐R1 and Maestro‐1 (mean difference = −0.018, p = 0.48). In ONHD eyes, mean VCDR measured 0.27 (Canon Xephilio OCT‐R1), 0.28 (Maestro‐1), and 0.41 (Maestro‐2), all significantly greater than zero ( p ≤ 0.019). Screen‐positive cases imaged with Maestro‐2 demonstrated large VCDR (mean = 0.73) despite normal or near‐normal retinal nerve fiber layer (RNFL)/ganglion cell complex (GCC) and visual fields. Conclusion Automated VCDR measurements vary by OCT device and diverge most in ONHD and large cups. Device‐aware, multiparameter interpretation may reduce misclassification in community screenings.