HUD Surgical Guidance for Toric Alignment

Gainesville Eye Associates100 enrolled

Overview

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 Type

INTERVENTIONAL

Allocation

Purpose

DIAGNOSTIC

Masking

NONE

Enrollment

100

Conditions

Cataract and IOL Surgery

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

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.

Outcomes

Primary Outcomes

Accuracy (measured in degrees of arc) using the Cassini Guidance system for calculated alignment axis for toric IOL implantation.

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.

Time frame: Total completion up to 12 months

Secondary Outcomes

Time efficiency (measured in seconds) of the Cassini Guidance System in eyes undergoing cataract surgery with toric IOL implantation.

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.