Retinal nerve fibre layer thickness measurement reproducibility improved with spectral domain optical coherence tomography
J S Kim, H Ishikawa, K R Sung, J Xu, G Wollstein, R A Bilonick, M L Gabriele, L Kagemann, J S Duker, J G Fujimoto, J S Schuman, J S Kim, H Ishikawa, K R Sung, J Xu, G Wollstein, R A Bilonick, M L Gabriele, L Kagemann, J S Duker, J G Fujimoto, J S Schuman
Abstract
Background/aims: To investigate retinal nerve fibre layer (RNFL) thickness measurement reproducibility using conventional time-domain optical coherence tomography (TD-OCT) and spectral-domain OCT (SD-OCT), and to evaluate two methods defining the optic nerve head (ONH) centring: Centred Each Time (CET) vs Centred Once (CO), in terms of RNFL thickness measurement variability on SD-OCT.
Methods: Twenty-seven eyes (14 healthy subjects) had three circumpapillary scans with TD-OCT and three raster scans (three-dimensional or 3D image data) around ONH with SD-OCT. SD-OCT images were analysed in two ways: (1) CET: ONH centre was defined on each image separately and (2) CO: ONH centre was defined on one image and exported to other images after scan registration. After defining the ONH centre, a 3.4 mm diameter virtual circular OCT was resampled on SD-OCT images to mimic the conventional circumpapillary RNFL thickness measurements taken with TD-OCT.
Results: CET and CO showed statistically significantly better reproducibility than TD-OCT except for 11:00 with CET. CET and CO methods showed similar reproducibility.
Conclusions: SD-OCT 3D cube data generally showed better RNFL measurement reproducibility than TD-OCT. The choice of ONH centring methods did not affect RNFL measurement reproducibility.
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Source: PubMed