Verion reference unit keratometer readings in comparison with IOL master 500, OPD scan III and Pentacam HR

Session Details

Session Title: Moderated Poster Session : Cataract - Cataract Surgery Equipment/ Instruments/ Surgical Devices/ OVDs

Session Date/Time: Tuesday 08/09/2015 | 14:00-15:00

Paper Time: 14:20

Venue: Poster Village: Pod 1

First Author: : M.Schultz GERMANY

Co Author(s): :    U. Oberheide   O. Kermani           

Abstract Details

Purpose:

The Verion reference unit is part of a surgical guidance system that enables the surgeon to measure the astigmatism and later on guide the correct alignment of a toric intraocular lens (IOL) during surgery. Hereby torsion errors with subsequent reduction of refractive correction can be minimized. The aim of this study was to compare the keratometer readings from the Verion reference unit with other devices that have a long standing history in ophthalmology and hereby ensure the validity of the measurements.

Setting:

Private Eye Hospital, Cologne, Germany

Methods:

In this retrospective study cataract patients with no other ocular pathologies were measured pre-op with four different devices and the keratometry readings were collected. Patients with diseases of the cornea, post corneal transplantation or refractive treatment of the cornea were excluded. 105 eyes with an average age of 68.6 years (±11.9 years) were included (58% female eyes, 50% right eyes). Measurements were performed between April and September 2014. The following devices were used: Verion reference unit (Alcon, Germany), IOL Master 500 (Zeiss, Germany), OPD Scan III (Nidek, Japan), Pentacam HR (Oculus, Germany).

Results:

With the measurement of radii (R1, R2) and the axis of the flat meridian the power of astigmatism and power vectors (J0, J45 and M) were calculated. The Verion reference unit was within the standard deviation of all other devices. The refractive power of a fictional IOL was calculated for emmetropia according to the Haigis' formula for all four devices. For all eyes a given anterior chamber depth and axial length was assumed. As a result the mean IOL power calculated was 22.23 ±2.25D (Verion), 22.27D ±2,20D (IOL Master 500), 22.51D ±2.17D (Pentacam) and 22.48D ±2.25D (OPD-Scan III), respectively.

Conclusions:

The K-readings of the Verion reference unit for surgical guidance of toric IOL are comparable to other established devices such as the IOL Master 500 (Zeiss, Germany), OPD Scan III (Nidek, Japan) or Pentacam HR (Oculus, Germany). Individual measurements have to be checked for plausibility in all devices.

Financial Interest:

NONE