First Clinical Results in 30 Eyes with a Novel Ocular Biometer for IOL Power Calculation

Arthur Cummings FRCS1,2, Gerard Kervick FRCOphth4, Diana Bogusevschi PhD2, Andrew Nolan PhD2, Michael Mrochen PhD2,3

1 Wellington Eye Clinic, Dublin, Ireland2 ClearSight Innovations, Dublin, Zurich3 IROC Science to Innovation, Zurich4 Mater Hospital, Cork

The authors (except for 4 ) have a financial interest in ClearSight Innovations

Background• IOL Power Calculation and Refraction Prediction in unusual

eyes remain challenging – Toric IOL’s, Post-refractive surgery eyes e.g. post-LASIK, post-RK.

• Accurate measurements of all ocular parameters combined with ray-tracing is a potential solution for both normal and unusual cases.

Purpose• A novel device consisting of Purkinje imaging technique

combined with an optical coherence method is employed in a feasibility study on IOL power calculation.

• The measured ocular parameters are compared with the Standard of Care (SOC) device (OB820, WaveLight)

• This will assess its viability for refraction prediction.

Method: Device• The novel biometry device provides accurate measurements of the following

parameters:– Cornea:

• Anterior and Posterior Radii, Conic Constants and Astigmatism– Lens Geometry:

• Anterior and Posterior Radii and Conic Constants.– Thickness values: – Central Corneal Thickness (CCT), Anterior Chamber Depth (ACD), Lens

Thickness (LT) and Axial Length (AL)

Method: Study Design• 34 subjects were enrolled (Informed consent provided)• All eyes underwent pupil dilation to at least 5 mm pupil diameter before

the eyes were measured with OB820, WaveLight (= Lenstar LS 900 from Haag-Streit).

• Following that the eyes were measured with the novel ocular biometer from ClearSight Innovations

• Comparison is performed between the two devices.

Patients• Enrolled patients stratification:

– The grouping of eyes included:• Normal, healthy – 10 eyes;• Varying degrees of cataracts – 16 eyes;• Pseudo-phakic – 14 eyes.

– Gender: 12 Male and 21 Female– OD/OS: 18 Right and 18 Left – Average Age of 59.9 years.

Results• The novel ocular biometer was able to measure and reconstruct all eye elements.• The comparisons with the SOC device showed high correlations:

Novel Biometer/ OB820AL 0.991 (p < 0.05)

ACD 0.985 (p < 0.05)

LT 0.993 (p < 0.05)

RAC 0.983 (p < 0.05)

RPC N/A

Results• It is shown that the novel device can be used for accurate IOL Power

Calculation and Refraction Prediction.• The SOC device did not provide any measurements of the Posterior

Cornea or Radii of Anterior and Posterior Crystalline Lens, which prohibits comparison.

• As refraction prediction is more sensitive to Radius of Anterior Cornea, Axial Length and ACD, we will consider these to be the parameters of interest.

Axial Length: Correlation and Bland-AltmanMirricon II versus OB820

ACD: Correlation and Bland-AltmanMirricon II versus OB820

Radius of Anterior Cornea: Correlation and Bland-AltmanMirricon II versus OB820

Conclusions• The novel biometry device is shown to provide comparable ocular

parameters to the OB820, WaveLight.

• It also has the capability of measuring additional elements, such as Posterior Cornea, Anterior and Posterior Crystalline Lens geometries.

• The novel ocular biometer provides the possibility of more accurate ray-tracing IOL prediction for both normal and unusual eyes.