How Big is the Hole? Measuring Intra- and Inter-Individual Agreement in Macular Hole Size Measurements.

ABSTRACT

PURPOSE: The size of a macular hole helps determine treatment planning and postoperative prognosis. The aim of this study was to examine intra- and inter-individual agreement in the measurement of full thickness macular hole (FTMH) size using optical coherence tomography (OCT) images. METHODS: Thirty OCT scans of FTMHs were reviewed by three vitreoretinal consultants and three vitreoretinal fellows. The FTMH size was recorded by each clinician independently and they repeated the measurements 3 weeks later. The repeatability of measurements was analysed using techniques of agreement measurement. RESULTS: The Coefficients of Repeatability (CR) for the intra-individual agreement were 46 µm, 73 µm and 60 µm for the consultant group and 44 µm, 60 µm and 57 µm for the fellow group. The Coefficients of Variation (CoV) of intra-individual repeatability were 3.8%, 5.9%, and 5.1% for the consultants and 3.5%, 5.2%, and 4.9% for the fellows. The CR for inter-individual agreement varied from 62 µm to 122 µm. There was no significant difference in repeatability of measurements between the consultant and the fellow groups (chi-squared, p = .95). CONCLUSIONS: Manual OCT FTMH diameter measurements show poor intra- and inter-individual repeatability. Future work should aim to develop an automated method for measuring macular holes.