City Research Online

The effects of ocular magnification on Spectralis spectral domain optical coherence tomography scan length

Ctori, I., Gruppetta, S. & Huntjens, B. (2015). The effects of ocular magnification on Spectralis spectral domain optical coherence tomography scan length. Graefe's Archive for Clinical and Experimental Ophthalmology, 253(5), pp. 733-738. doi: 10.1007/s00417-014-2915-9


The purpose of this study was to assess the effects of incorporating individual ocular biometry measures of corneal curvature, refractive error, and axial length on scan length obtained using Spectralis spectral domain optical coherence tomography (SD-OCT).

Two SD-OCT scans were acquired for 50 eyes of 50 healthy participants, first using the Spectralis default keratometry (K) setting followed by incorporating individual mean-K values. Resulting scan lengths were compared to predicted scan lengths produced by image simulation software, based on individual ocular biometry measures including axial length.

Axial length varied from 21.41 to 29.04 mm. Spectralis SD-OCT scan lengths obtained with default-K ranged from 5.7 to 7.3 mm, and with mean-K from 5.6 to 7.6 mm. We report a stronger correlation of simulated scan lengths incorporating the subject’s mean-K value (ρ = 0.926, P < 0.0005) compared to Spectralis default settings (ρ = 0.663, P < 0.0005).

Ocular magnification appears to be better accounted for when individual mean-K values are incorporated into Spectralis SD-OCT scan acquisition versus using the device’s default-K setting. This must be considered when taking area measurements and lateral measurements parallel to the retinal surface.

Publication Type: Article
Additional Information: The final publication is available at Springer via
Publisher Keywords: Optical coherence tomography, Axial length, Scan length, Spectralis, Keratometry
Subjects: R Medicine > RE Ophthalmology
Departments: School of Health & Psychological Sciences > Optometry & Visual Sciences
SWORD Depositor:
[thumbnail of Final Manuscript - for repository.pdf]
Text - Accepted Version
Download (276kB) | Preview


Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email


Downloads per month over past year

View more statistics

Actions (login required)

Admin Login Admin Login