Niklas Mohr1, Mehdi Shajari1,2, Daniel Krause1, Stefan Kassumeh1, Jakob Siedlecki1,3, Siegfried G Priglinger1,3, Wolfgang J Mayer1, Nikolaus Luft4,3.
Abstract
PURPOSE: To evaluate the capability of wide-field spectral-domain optical coherence tomography (SD-OCT) corneal sublayer pachymetry to distinguish between keratoconus and pellucid marginal degeneration (PMD).
METHODS: This prospective cross-sectional study included 69 eyes (59 with keratoconus and 10 with PMD) of 69 patients. All patients were examined three subsequent times with the RTVue XR system. Pachymetry maps of the total cornea (CT), the epithelium (ET) and the stroma were generated using the onboard software. For analysis of reliability, the coefficients of variation and intraclass correlation coefficients (ICC) were calculated. Receiver operating characteristic analyses were performed to elaborate the most accurate pachymetric parameters for distinguishing between PMD and keratoconus.
RESULTS: Overall repeatability of (sublayer) pachymetry was comparably good in both keratoconus (ICC ranging between 0.827 and 0.986) and PMD (ICC ranging between 0.753 and 0.998). Measurement reliability in keratoconic eyes was a negative function of Kmax (p<0.05). As compared with keratoconus, PMD exhibited higher CT (526±31 µm vs 503±30 µm; p=0.02) and ET (56±7 µm vs 51±5 µm; p=0.02) in the inferotemporal 2-5 mm sector as well as lower ET in the inferior 7-9 mm sector (52±5 µm vs 57±5 µm; p<0.01). The calculated ratio between CT in the inferotemporal 2-5 mm and in the inferior 7-9 mm sector yielded the highest diagnostic accuracy for distinguishing between PMD and keratoconus with an area under the curve of 0.977 and an optimal cut-off value of 0.90.
CONCLUSION: Wide-field SD-OCT corneal sublayer pachymetry showed good reliability in PMD and keratoconus and may be useful to differentiate between the two ectatic diseases. © Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.
PURPOSE: To evaluate the capability of wide-field spectral-domain optical coherence tomography (SD-OCT) corneal sublayer pachymetry to distinguish between keratoconus and pellucid marginal degeneration (PMD).
METHODS: This prospective cross-sectional study included 69 eyes (59 with keratoconus and 10 with PMD) of 69 patients. All patients were examined three subsequent times with the RTVue XR system. Pachymetry maps of the total cornea (CT), the epithelium (ET) and the stroma were generated using the onboard software. For analysis of reliability, the coefficients of variation and intraclass correlation coefficients (ICC) were calculated. Receiver operating characteristic analyses were performed to elaborate the most accurate pachymetric parameters for distinguishing between PMD and keratoconus.
RESULTS: Overall repeatability of (sublayer) pachymetry was comparably good in both keratoconus (ICC ranging between 0.827 and 0.986) and PMD (ICC ranging between 0.753 and 0.998). Measurement reliability in keratoconic eyes was a negative function of Kmax (p<0.05). As compared with keratoconus, PMD exhibited higher CT (526±31 µm vs 503±30 µm; p=0.02) and ET (56±7 µm vs 51±5 µm; p=0.02) in the inferotemporal 2-5 mm sector as well as lower ET in the inferior 7-9 mm sector (52±5 µm vs 57±5 µm; p<0.01). The calculated ratio between CT in the inferotemporal 2-5 mm and in the inferior 7-9 mm sector yielded the highest diagnostic accuracy for distinguishing between PMD and keratoconus with an area under the curve of 0.977 and an optimal cut-off value of 0.90.
CONCLUSION: Wide-field SD-OCT corneal sublayer pachymetry showed good reliability in PMD and keratoconus and may be useful to differentiate between the two ectatic diseases. © Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.
Entities:
Keywords:
Cornea; Degeneration; Imaging
Mesh:
Year: 2020
PMID: 33055086 DOI: 10.1136/bjophthalmol-2020-316496
Source DB: PubMed Journal: Br J Ophthalmol ISSN: 0007-1161 Impact factor: 4.638