Measurements
Optical coherence biometry revolutionised cataract surgery, the LENSTAR® is about to revolutionise optical biometry.
State-of-the-art, multivariable IOL calculation formulae demand more than just the axial length and keratometry values of the eye. LENSTAR® provides the user with a complete biometrical assessment of the patient’s eye in a single measurement procedure, including lens thickness, anterior chamber depth (lens position) and retinal thickness.
Central Corneal Thickness (CCT)
CCT is measured using optical coherence technology, leading to unmatched accuracy and precision. Reproducibility of this measurement is as good as ± 2 microns, providing one of the base parameters for possible laser correction of the cataract surgery.
Anterior Chamber Depth (ACD)
Just like all other length measurements ACD is assessed with optical coherence technology (OLCR). Combined with the CCT measurement, LENSTAR® provides the user with the anatomical (= Aqueous Depth = AD) as well as ACD as measured by ultrasound biometers.
Lens Thickness (LT)
Modern multivariable IOL calculation formulae use the patient's lens thickness as an input parameter. LENSTAR® provides the user with the measurement of true lens thickness on the visual optical line of the patient using optical coherence technology (OLCR). No estimation or additional ultrasound measurement is required to get this important parameter.
Axial Length (AL)
Optical coherence technology using a superluminescent diode as light source allows the measurement of the axial length of the patient’s eye on the visual optical line in highest precision and through dense cataracts.
Retinal Thickness (RT)
An easy to use manual selection of the retinal peaks in the A-scan enables the user to measure RT (distance between the ILM and the RPE) and to calculate IOL based on the individual RT. Without any user interaction, a typical value for the RT is displayed and employed for IOL calculation. As a result LENSTAR delivers comparable results to existing ultrasound and optical biometers.
Keratometry
A 32 marker pattern ensures precise assessment of the corneal curvature. The distribution of the marker on two concentric circles allows stable measurements even with non-compliant patients.
White to White Distance
For sulcus fixated IOLs and for the calculation of the IOL power using the Holladay II formula, LENSTAR® measures white to white distance (horizontal Iris width).
Pupillometry
The software allows for measurement of the patient’s pupil diameter in ambient light condition.
Eccentricity of the Visual Axis
The eccentricity of the visual optical line is assessed with respect to white-to-white as well as to the pupil centre. Both are important parameters for laser refractive procedures.
Special Eye Conditions
All of the described measurements are available for the measurement of the “normal” cataract patient as well as for aphakic, pseudoaphakic and silicone oil filled eye conditions. In case of an error, you may even change the selected eye condition after completion of the measurement procedure.
