A comparison of two methods to measure choroidal thickness by enhanced depth imaging optical coherence tomography

Autor: Tunde Peto, Anders Højslet Vestergaard, Ernst Goldschmidt, Nina Jacobsen, Jakob Grauslund, Anna Stage Vergmann, Kristian Lundberg
Jazyk: angličtina
Rok vydání: 2019
Předmět:
Zdroj: Lundberg, K, Vergmann, A S, Vestergaard, A H, Jacobsen, N, Goldschmidt, E, Peto, T & Grauslund, J 2019, ' A comparison of two methods to measure choroidal thickness by enhanced depth imaging optical coherence tomography ', Acta Ophthalmologica, vol. 97, no. 1, pp. 118-120 . https://doi.org/10.1111/aos.13272
University of Southern Denmark
Lundberg, L K, Vestergaard, A H, Vergmann, A S, Jacobsen, N, Goldschmidt, E, Peto, T & Grauslund, J 2016, ' A comparison of two methods to measure choroidal thickness by enhanced depth imaging optical coherence tomography ', NOK 2016, Århus, Denmark, 08/06/2016-12/06/2016 .
DOI: 10.1111/aos.13272
Popis: Introduction The choroid is believed to be involved in the pathophysiology of several vision threatening diseases such as age-related macular degeneration, central serous chorioretinopathy, inflammatory disorders and myopic macular degeneration. Enhanced depth imaging spectral-domain optical coherence tomography (EDI-SD OCT) has made it possible to visualize the choroid, and it is generally accepted that Heidelberg Spectralis OCT provides valid measurements of choroidal thickness (CT), although no fully automated software is commercially available. Two methods for CT-measurement are available in the Heidelberg software, but to our knowledge these have not been compared. Hence, the purpose of this study was to evaluate and validate the Segmentation method and the Ruler method for CT-measurement. Methods We used the Heidelberg Spectralis (Heidelberg Engineering, Heidelberg, Germany) to record EDI-SD-OCT and Heidelberg Eye Explorer software (Version 1.9.10.0) to perform measurements. In a 30 degree scan angle, foveal-centered radial scans of 4 sections (with an art mode of 50 frames) were obtained. In accordance with other studies, we made 17 CT measurements per scan at the following targets: Subfoveal, 1 and 3 millimeter in each direction of fovea. Only the horizontal and vertical sections were selected for analysis. A total of 9 targets per eye that represented anatomically different choroidal locations were analysed for every subject. We used 2 different methods from the Heidelberg Explorer software to measure the CT: 1: Segmentation method; by the use of the thickness profile window we manually edited and moved the inner limiting membrane (ILM) line to the choroid-scleral border (CSB), while we kept the automated defined Bruchs membrane (BM). Hereafter, the software calculated the vertical distance between the 2 lines that represented the CT. 2: Ruler method; by the use of the display window and the ruler tool we measured the distance between 2 manually selected targets representing the CSB and BM. In both methods we defined the CT as the vertical distance between the hyper reflective line of the BM and the CSB. The CT was measured by 2 independent graders, and intra- and intergrader intraclass correlation coefficients (ICC) were calculated. Additionally, we recorded the time used for each measurement. Results Data from 10 healthy subjects, 6 females and 4 males (age 15 to 17 years) was obtained. For the Segmentation method and the Ruler method, mean subfoveal CT were 354.9 ±93.6 μm and 360.75 ±104.2 μm, respectively (P=0.85). For all 9 measurement targets the mean intragrader ICC were 0.99 ±0.01 and 0.98 ±0.02 for the Segmentation method and the Ruler method, respectively (P=0.38). Corresponding values for mean intergrader ICC were 0.97 ±0.027 and 0.95 ±0.03 (P=0.17). A shorter mean time was found for the Segmentation method (7.3 ±1.6 minutes vs. 9.0 ±1.8 minutes, P
Databáze: OpenAIRE
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