HUD Surgical Guidance for Toric Alignment (CG-Toric)

January 6, 2026 updated by: Gainesville Eye Associates

Clinical Evaluation of a Novel Intraoperative Guidance System for Accurate Toric IOL Positioning in Cataract Surgery

This study aims to assess the accuracy of toric intraocular lens (IOL) alignment axes as calculated and displayed by a novel digital guidance system. In addition, it evaluates the time required to initiate surgical guidance and postoperative refractive astigmatism following toric IOL implantation.

This single-surgeon, single-site, prospective, non-invasive observational study evaluated the accuracy of toric IOL alignment axes calculated and displayed by the digital guidance system (Cassini Technologies, B.V.) in 100 eyes. The intraoperatively calculated alignment axes were compared to preoperative measurements to assess their accuracy (in degrees). Postoperative outcomes, including residual refractive astigmatism (diopters) and visual acuity (Snellen), were recorded at 1 month postoperatively.

Study Overview

Status

Recruiting

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

100

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

    • Georgia
      • Gainesville, Georgia, United States, 30501
        • Recruiting
        • North Georgia Eye Associates
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion criteria:

  • Patients undergoing uncomplicated cataract surgery with toric IOL implantation,
  • Eyes implanted with a toric IOL.

Exclusion criteria:

  • Ocular comorbidity likely to impair postoperative visual acuities, or
  • History of ocular trauma or zonular instability, or
  • Previous refractive surgery, or
  • Irregular corneal astigmatism or keratoconus, or
  • Patients with physical or intellectual disabilities that may prevent reliable fixation or comprehension (e.g. Down's Syndrome, Parkinson's Disease), or
  • Patients with unreliable biometry measurements, or
  • Severe dry eye disease or ocular surface disease.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

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

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Other: Surgical guidance for Toric IOL alignment intraoperatively
Interventional
Cassini Guidance with HUD

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Accuracy (measured in degrees of arc) using the Cassini Guidance system for calculated alignment axis for toric IOL implantation.
Time Frame: Total completion up to 12 months

Primary Endpoint:

1. Accuracy of the calculated alignment axis (degrees of arc = angular degrees)

  • Definition: The angular difference between the alignment axis for toric IOLs as determined with the CGS and the intended alignment axis as determined with the Cassini Ambient.
  • Thresholds of interest: ≤3°, ≤5°, ≤10°, >10°.
  • Justification: Misalignment greater than 10° results in a clinically significant loss of toric correction (approximately 33%) (Quesada et al., 2022; Hu, 2023), making this a meaningful accuracy benchmark.
Total completion up to 12 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Time efficiency (measured in seconds) of the Cassini Guidance System in eyes undergoing cataract surgery with toric IOL implantation.
Time Frame: Total completion up to 12 months

Secondary Endpoint:

1. The time (measured in seconds) required to initiate (0 seconds) and finish (x seconds) surgical guidance using the Cassini Guidance System in 100 eyes undergoing toric IOL implantation.

Total completion up to 12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

November 4, 2025

Primary Completion (Estimated)

October 1, 2026

Study Completion (Estimated)

October 31, 2026

Study Registration Dates

First Submitted

December 4, 2025

First Submitted That Met QC Criteria

January 6, 2026

First Posted (Actual)

January 8, 2026

Study Record Updates

Last Update Posted (Actual)

January 8, 2026

Last Update Submitted That Met QC Criteria

January 6, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 2025-0104

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

Yes

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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