Efficiency and measurements agreement between swept-source OCT
and low-coherence interferometry biometry systems
Jorge A. Calvo-Sanz
Received: 2 July 2017 / Revised: 5 January 2018 / Accepted: 12 January 2018 /Published online: 1 February 2018
Springer-Verlag GmbH Germany, part of Springer Nature 2018
Purpose To compare and evaluate the agreement between the measurements obtained with a swept-source optical coherence
tomography (OCT)-based biometer, the IOLMaster® 700 (IOLM), and those obtained by an optical biometer based on optical
low-coherence interferometry (OLCI), the Aladdin (ALD); To evaluate the ability to perform biometric measurements in those
eyes with transparency alterations.
Methods Fifty-five eyes of 55 subjects were included in this study. Axial length (AL), corneal power (K, in diopters) and its
astigmatism, anterior chamber depth (ACD), central corneal thickness (CCT), and lens thickness (LT) measures were obtained
within both biometers, Zeiss IOLMaster 700 and Topcon Aladdin. Results were analyzed and compared using the Student’s
paired samples t-test, Bland–Altman analysis and intraclass correlation coefficient (ICC).
Results Mean age was 73.12 ± 2.63 (62–89 years). The IOLM mean AL, K, and LT values did not show a statistically significant
difference from ALD values and showed excellent agreement and correlation (ICC = 1.000, 0.970, 0.952). IOLM measured a
lower mean ACD (−0.036 mm) and higher CCT measurements (9.296 μm). Those results were statistically different (p <0.001in
both cases) but showed an excellent correlation coefficients (ICC = 0.994, 0.938). IOLM was able to obtain measures from all the
eyes examined, while ALD did not measure in two cases with dense nuclear cataract. ALD showed spherical K measures in
7.27% of cases.
Conclusion Overall a quite good agreement between IOLM and ALD was found. ALD showed spherical keratometry measures
in 7.27% of cases. IOLMaster 700 was more effective in obtaining AL measurements in eyes with dense cataracts.
The possibility of clinical use of different biometric and intra-
ocular structures measurement systems, such as partial coher-
ence interferometry (PCI), optical low-coherence interferom-
etry (OLCI), optical low-coherence reflectometry (OLCR)
and swept-source optical coherence tomography (SS-OCT),
requires an analysis of efficacy, accuracy, and reproducibility
of the different systems and measurement techniques.
Correlation between different optical devices has been widely
studied previously [1–10], but none of those papers analyzed
correlation between IOLMaster® 700 (Carl Zeiss Meditec
AG, Germany) (IOLM) and Topcon Aladdin (Topcon
Corporation, Tokyo, Japan) low-coherence interferometry bi-
ometry. Therefore, although both biometers have been ana-
lyzed and studied by comparing their results with the PCI gold
standard with very good results, it is necessary to make a
comparative analysis between them directly.
Nowadays PCI technique is considered as gold standard
since IOLMaster appeared in 1999 [1, 11], thanks to the ease
of measurement and high accuracy and repeatability obtained
with measurements, matching the precision of their results to
those obtained with the immersion ultrasound technique .
Topcon Aladdin biometer (ALD), that uses OLCI technol-
ogy, has been compared with several devices [3, 5, 7, 10].
Those studies showed that, independently of measure tech-
nique used, measurement correlation between devices was
* Jorge A. Calvo-Sanz
Instituto de Ciencias Visuales, INCIVI, c\ Ana Teresa, 24 - 28023,
Ophthalmologist, Instituto de Ciencias Visuales, INCIVI,
Graefe's Archive for Clinical and Experimental Ophthalmology (2018) 256:559–566