Patients sometimes ask why Blue Fin Vision® uses two biometry machines when most clinics use one. The answer is that the two are not the same machine. They are not even the same kind of measurement. They are two complementary platforms, each engineered to do something the other cannot.
Lenstar LS900
The Lenstar LS900 is an optical low-coherence reflectometer that uses an 820 nm super-luminescent diode to measure the optical distances between the corneal apex, the lens surfaces and the retina. It is one of the most widely validated optical biometers in clinical use, with reproducibility coefficients under 0.9% for all measured parameters¹. It produces a dual-zone keratometric reading optimised for IOL power calculation and feeds its measurements into a built-in calculator running multiple modern formulae: Haigis, Barrett Universal II, Hill-RBF, SRK/T and Hoffer Q.
Independent agreement studies have confirmed that Lenstar axial length and IOL power output are biometrically equivalent to those derived from partial coherence interferometry, which is the long-established reference standard for optical biometry². This is the platform whose output feeds directly into the IOL calculation at Blue Fin Vision®.
REVO FC OCT
The REVO FC is a spectral-domain OCT platform that performs axial length biometry, anterior segment OCT, full corneal topography and posterior segment OCT in a single device. Its B-OCT axial length measurement has been validated against the swept-source IOLMaster 700 with intraclass correlation coefficients of 1.000 for axial length in both healthy and cataractous eyes³. Unlike optical biometry alone, B-OCT provides visual confirmation: the operator can see the OCT trace and the structural landmarks used to derive each measurement.
Why Both, Not One
Lenstar tells us what lens to implant. REVO FC tells us whether we should trust that answer. The Lenstar provides the value entered into the IOL formula. The REVO FC provides the surrounding evidence: tomographic confirmation of axial length, full anterior and posterior corneal topography, the pachymetric map, posterior segment OCT screening, and the real (total) corneal power that no two-surface keratometer can produce.
Two devices, two technologies, one independently confirmed plan.
Clinical Takeaway
Lenstar and REVO FC are complementary, not duplicate. Lenstar produces the IOL calculation. REVO FC verifies it and provides corneal and retinal evidence the Lenstar cannot.
References
- Sikorski BL, Suchon P. OCT Biometry (B-OCT): a new method for measuring ocular axial dimensions. J Ophthalmol. 2019;2019:9192456. doi:10.1155/2019/9192456
- Jasvinder S, Khang TF, Sarinder KKS, Loo VP, Subrayan V. Agreement analysis of LENSTAR with other techniques of biometry. Eye (Lond). 2011;25(6):717-724. doi:10.1038/eye.2011.28
- Cruysberg LPJ, Doors M, Verbakel F, Berendschot TTJM, De Brabander J, Nuijts RMMA. Evaluation of the Lenstar LS 900 non-contact biometer. Br J Ophthalmol. 2010;94(1):106-110. doi:10.1136/bjo.2009.161729
Related Topics
- Double Biometry for Every Patient
- Why Blue Fin Vision® Performs Double Biometry for Every Cataract Patient
- How a 0.01 mm Difference Can Change Cataract Surgery Outcomes
- Why Most Cataract Clinics Only Use One Biometry Machine, and Why We Don’t
- How Double Biometry Helps Reduce Cataract Surgery Enhancements
- Lenstar vs REVO FC: Why Blue Fin Vision® Uses Both Before Lens Surgery
- What Patients Can Expect During a Blue Fin Vision® Biometry Workup
- Why Trifocal and Toric IOLs Need More Precise Biometry Than Standard Lenses
- Why Topography Quality Matters, and What a TQF Warning Tells Us
