Digital Marking Systems

Comparing Two Digital Marking Systems

Comparison of the alignment axis of the Alcon Verion and the Zeiss Callisto alignment systems intraoperatively

Study Overview

• Status: Recruiting
• Conditions: Cataract
• Intervention / Treatment: Device: digital marking system

Detailed Description

In most patients undergoing cataract surgery, emmetropia can be achieved by implantation of a monofocal intraocular lens (IOL). However, several studies have shown that approximately 20% to 30% of patients who undergo cataract surgery have a preexisting corneal astigmatism of 1.25 diopters (D) while the prevalence of corneal astigmatism >2.00 D is 8% and over >3.00 D 2.6%. This astigmatism, if not corrected during surgery, leads to postoperative spectacle dependence. In patients without contraindications and a desire to achieve postoperative freedom from spectacles for distance vision, correction of astigmatism can be achieved at the time of surgery by using toric IOLs.

A number of factors relating to corneal astigmatism are critical to lens selection and positioning.The most important factors are the preoperative corneal measurements and the correct alignment of the toric lens itself.

Each degree of deviation results in a 3% reduction in astigmatism correction. The introduction of digital marking systems is intended to minimize the disadvantages of manual marking, such as tilting of the head during marking, incorrect and smudged marking. In addition to several different manual marking methods, there is also a range of digital markers which have been proven to be equal or even better than manual marking. These include among others the Callisto Eye with Z-Align and the Alcon VERION Digital Marker. The principle of these digital marking systems is based on a preoperative photo which is recorded in the course of biometry where the keratometry values are obtained. In the further course, the steep axis is determined on the basis of this image and the target axis is projected on to the eye intraoperatively. Beside the ideal implantation axis for the T-IOL, the size of the capsulorhexis and position, as well as incision placement can be displayed.

In the course of this study, we will investigate the alignment axis of the two most used digital guidance systems from Alcon and Zeiss. A head to head comparison has already been carried out by Hura et al. in 2017.

15 eyes of 15 patients will be included into this study. There will only be one preoperative study visit, on the day of surgery, where reference pictures with a slitlamp camera and the biometers will be taken.

• Study Type: Interventional
• Enrollment (Anticipated): 15
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Johannes Zeilinger, MD; Phone Number: 57564 +43 (1) 91021; Email: office@viros.at
• Study Contact Backup: Name: Oliver Findl, MD; Phone Number: 57564 +43 (1) 91021; Email: office@viros.at

Study Locations

• Austria
  • Vienna, Austria, 1140
    • Recruiting
    • Vienna Institute for Research in Ocular Surgery (VIROS), Hanusch Hospital
    • Contact: Johannes Zeilinger, MD; Phone Number: 57564 +43 (1) 91021; Email: office@viros.at
    • Contact: Oliver Findl, MD; Phone Number: 57564 +43 (1) 91021; Email: office@viros.at

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 21 years to 105 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• age-related cataract and scheduled for cataract surgery
• age 21 or older
• written informed consent prior to surgery

Exclusion Criteria:

• dense cataract or corneal pathology that would significantly influence the measurements
• previous ocular surgery, ocular inflammation, or ocular trauma
• nystagmus or pathologies that might affect patient's fixation
• pregnancy
• corneal astigmatism > 1.5 dpt. or need for a toric IOL

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Verion and Callisto; Alignment axis will be analysed with both, the Verion and the Callisto, digital marking system in the same eye of the same patient	Device: digital marking system; Verion or Callisto, digital marking system

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Alignment axis	Difference in aligment axis will be assessed with the Verion and the Callisto digital marking system	24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Loss of Tracking	Loss of Tracking will be analysed during the different steps of surgery	24 months
Luminance	Luminance necessary for registration will be analysed using a luxmetre	24 months

Collaborators and Investigators

• Sponsor: Vienna Institute for Research in Ocular Surgery

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2021
• Primary Completion (Anticipated): July 1, 2023
• Study Completion (Anticipated): July 1, 2024

Study Registration Dates

• First Submitted: January 21, 2022
• First Submitted That Met QC Criteria: January 21, 2022
• First Posted (Actual): February 2, 2022

Study Record Updates

• Last Update Posted (Actual): February 2, 2022
• Last Update Submitted That Met QC Criteria: January 21, 2022
• Last Verified: January 1, 2022

More Information

Terms related to this study

• Keywords: Astigmatism; Digital Marking Systems
• Additional Relevant MeSH Terms: Eye Diseases; Lens Diseases; Cataract
• Other Study ID Numbers: VE

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No