Comparison of Drusen Volume Assessed by Two Different OCT Devices

Marco Beck; Devika S Joshi; Lieselotte Berger; Gerd Klose; Sandro De Zanet; Agata Mosinska; Stefanos Apostolopoulos; Andreas Ebneter; Martin S Zinkernagel; Sebastian Wolf; Marion R Munk

doi:10.3390/jcm9082657

Comparison of Drusen Volume Assessed by Two Different OCT Devices

J Clin Med. 2020 Aug 17;9(8):2657. doi: 10.3390/jcm9082657.

Authors

Affiliations

¹ Department of Ophthalmology, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland.
² Carl Zeiss Meditec, Inc., Tokyo 102-0083, Japan.
³ RetinAI Medical AG, 3010 Bern, Switzerland.
⁴ Bern Photographic Reading Center, Inselspital, Bern University Hospital, University of Bern, 3010 Bern, Switzerland.

Abstract

To compare drusen volume between Heidelberg Spectral Domain (SD-) and Zeiss Swept-Source (SS) PlexElite Optical Coherence Tomography (OCT) determined by manual and automated segmentation methods. Thirty-two eyes of 24 patients with Age-Related Macular Degeneration (AMD) and drusen maculopathy were included. In the central 1 and 3 mm ETDRS circle drusen volumes were calculated and compared. Drusen segmentation was performed using automated manufacturer algorithms of the two OCT devices. Then, the automated segmentation was manually corrected and compared and finally analyzed using customized software. Though on SD-OCT, there was a significant difference of mean drusen volume prior to and after manual correction (mean difference: 0.0188 ± 0.0269 mm³, p < 0.001, corr. p < 0.001, correlation of r = 0.90), there was no difference found on SS-OCT (mean difference: 0.0001 ± 0.0003 mm³, p = 0.262, corr. p = 0.524, r = 1.0). Heidelberg-acquired mean drusen volume after manual correction was significantly different from Zeiss-acquired drusen volume after manual correction (mean difference: 0.1231 ± 0.0371 mm³, p < 0.001, corr. p < 0.001, r = 0.68). Using customized software, the difference of measurements between both devices decreased and correlation among the measurements improved (mean difference: 0.0547 ± 0.0744 mm³, p = 0.02, corr. p = 0.08, r = 0.937). Heidelberg SD-OCT, the Zeiss PlexElite SS-OCT, and customized software all measured significantly different drusen volumes. Therefore, devices/algorithms may not be interchangeable. Third-party customized software helps to minimize differences, which may allow a pooling of data of different devices, e.g., in multicenter trials.

Keywords: AMD; age-related macular degeneration; drusen; drusen volume; optical coherence tomography; retinal imaging analysis; retinal pigment epithelium; segmentation; spectral-domain OCT; swept-source OCT.