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29 clinical studies listed.

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Astigmatism

Tundra lists 29 Astigmatism clinical trials. Each listing includes eligibility criteria, study locations, and direct links to research sites in the Tundra directory.

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NOT YET RECRUITING

NCT07502456

Clareon TruPlus Study

The purpose of this research study is to generate safety and performance data for Clareon TruPlus Monofocal Intraocular Lenses (IOLs). IOLs are medical devices that are implanted in the eye during cataract surgery to restore clear vision after the cloudy natural lens has been removed. IOLs are intended to remain in the eyes for the duration of the patient's lifetime.

Gender: All

Ages: 22 Years - Any

Updated: 2026-04-03

2 states

Aphakia
Astigmatism
RECRUITING

NCT07303920

Wear Experience With Daily Disposable Contact Lenses for Astigmatism Over a Long-Wear Day

The purpose of this study to assess the wear experience of people who have astigmatism when wearing a daily disposable contact lens for astigmatism over long days of wear.

Gender: All

Ages: 18 Years - 40 Years

Updated: 2026-03-25

1 state

Astigmatism
RECRUITING

NCT07284966

Comfort and Vision With TOTAL30 Multifocal Lenses

This study is a single-arm, prospective, observational study conducted at one site to evaluate the comfort and vision of the TOTAL30 Multifocal (T30MF) contact lenses over the course of long wear days. The study will assess the proportion of positive subjective Visual Analog Scale (VAS) assessments of comfort and vision at 10, 12, 14, and 16 hours of wear on Days 1, 7, 14, and 30. Additionally, the study will explore subjective assessments of lens comfort using the CLDEQ-8 survey and measure logMAR visual acuity at both distance and near at Visit 1, Visit 2, and after 1 month of lens wear. Participants will undergo three site visits, with at-home surveys conducted at specified intervals to gather real-time data on comfort and vision.

Gender: All

Ages: 40 Years - Any

Updated: 2026-02-09

1 state

Myopia
Presbyopia
Astigmatism
RECRUITING

NCT07294716

Improving Visual Quality in Patients With Irregular Corneas Using Asymmetrical Toric Intraocular Lenses

Cataract surgery in patients with irregular corneas presents unique challenges, primarily due to the high variability in keratometry and corneal tomography measurements, which complicates accurate intraocular lens (IOL) calculations. In these patients, therapeutic options are currently limited to either non-toric IOLs and rigid contact lenses postoperatively or conventional toric IOLs for the reduction of total astigmatism within cataract surgery. While conventional toric IOLs may be beneficial in selected cases with a stable astigmatic pattern and clear axis, their effectiveness is largely limited, as significant irregularity and higher order aberrations reduce predictability, accuracy of formulae, and refractive outcomes. Therefore, the development of a reliable method to reduce total astigmatism - including irregular components - would represent a major advancement, potentially improving both visual function and patient quality of life. The aim of this exploratory study is to evaluate the effectiveness of customized toric intraocular lenses (AMILens Individual, AMIPLANT GmbH, Germany) in reducing total corneal astigmatism in patients with a significant irregular astigmatic component. These lenses are designed to address corneal aberrations up to the 6th Zernike order, thereby extending correction beyond the capabilities of conventional toric IOLs. To our knowledge, no clinical study has yet investigated this novel approach.

Gender: All

Ages: 21 Years - Any

Updated: 2026-01-26

Irregular Astigmatism
Astigmatism
Cataract and IOL Surgery
RECRUITING

NCT07078799

Wavefront-guided LASIK Surgery Compared to Ray Tracing-Guided LASIK Surgery

We are enrolling participants aged 22 and older to have LASIK surgery in both eyes. We will perform wavefront-guided LASIK in one eye and ray tracing-guided LASIK in the fellow eye of each participant. We are trying to see if there are any differences in the efficacy between the two types of LASIK procedures.

Gender: All

Ages: 22 Years - 59 Years

Updated: 2026-01-22

1 state

Myopia
Astigmatism
RECRUITING

NCT07140653

Arcuate Incisions With Light Adjustable Lens for Astigmatism Correction in Lens Surgery

This study aims to evaluate the safety and effectiveness of femtosecond laser arcuate corneal relaxing incisions (AK) combined with Light Adjustable Lens (LAL) implantation for correcting pre-existing corneal astigmatism in patients undergoing cataract or refractive lens exchange surgery. Postoperative assessments will focus on residual refractive astigmatism, visual outcomes, patient satisfaction, and the incidence of adverse events. Arcuate keratotomy and toric IOLs are well-established methods for astigmatism correction, and this study will compare their combined effectiveness using advanced femtosecond laser technology.

Gender: All

Ages: 21 Years - Any

Updated: 2025-12-22

2 states

Astigmatism
NOT YET RECRUITING

NCT07240480

Assessing the Turkish DDIVAT for Visual Acuity Measurement

The goal of this observational methodological study is to validate the Turkish version of the DDIVAT visual acuity measuring device in a Turkish-speaking adult population. The main questions it aims to answer are: Does the Turkish version of the DDIVAT provide reliable and valid visual acuity measurements in Turkish speakers? Are the results of the DDIVAT comparable to those obtained with the standard Snellen chart used in clinical practice? Researchers will compare DDIVAT visual acuity test results with Snellen chart results to see if both methods produce consistent measurements. Participants will: Be adults aged 18 years or older, including both patients and healthy volunteers. Undergo visual acuity testing using the DDIVAT system displayed on a smart TV connected to the university server. Have their visual acuity re-measured using the standard Snellen optotype under the same conditions. No medication or invasive procedure will be used. The study carries no risk to participants.

Gender: All

Ages: 18 Years - Any

Updated: 2025-12-04

Visual Acuity
Refractive Errors
Myopia
+2
NOT YET RECRUITING

NCT06785194

Revive Toric RWE Study

This is a post-market observational clinical investigation. The objective of this observational study is to evaluate the visual performance and HCP satisfaction of REVIVE samfilcon B custom toric contact lenses.

Gender: All

Ages: 18 Years - Any

Updated: 2025-11-28

2 states

Astigmatism
RECRUITING

NCT07232615

A Planned Study at Multiple Sites is Being Done to Compare the Results of Two Types of Trifocal Toric Intraocular Lenses Used in Cataract Surgery

To evaluate the clinical outcomes and patient satisfaction of two commercially available trifocal toric intraocular lenses Primary Objective: To compare the distance-corrected intermediate visual acuity between the two trifocal toric intraocular lenses. Secondary Objectives: To assess and compare the safety of two trifocal toric intraocular lenses.

Gender: All

Ages: 21 Years - Any

Updated: 2025-11-18

4 states

Presbyopia Correction
Astigmatism
Cataract
RECRUITING

NCT07127757

Clinical Evaluation of WaveLight Plus LASIK

This study is a single-site, single-arm, prospective, observational study of subject satisfaction, quality of vision, and quality of life after bilateral LASIK surgery. Subjects will be assessed up to 3 months post-operatively. Clinical evaluations will include refractive outcomes, visual acuity, and administration of the adapted PROWL and Low Luminance Questionnaire (LLQ-32) Questionnaire.

Gender: All

Ages: 18 Years - Any

Updated: 2025-10-02

1 state

Myopia
Astigmatism
RECRUITING

NCT07201298

A Three-Phase Contralateral Comparison of Ray-Tracing Guided LASIK Versus Three Other Refractive Surgery Platforms to Correct Myopia or Myopia With Astigmatism

This purpose of this study is to compare a new form of LASIK called Ray Tracing Guided LASIK to 3 other forms of corneal refractive surgery: 1. KLEx (KeratoLenticule Extraction) using the Zeiss Visumax 800 Laser, 2. WFO LASIK (Wavefront Optimized LASIK) using the Alcon EX500 Laser, and 3. Topography Guided LASIK (Contoura LASIK) also using the Alcon EX500 Laser.

Gender: All

Ages: 22 Years - 50 Years

Updated: 2025-10-01

1 state

Myopia
Astigmatism
RECRUITING

NCT07084844

Patient Reported Outcomes With WaveLight Plus LASIK

This study is a single-site, single-arm, prospective, observational study of subject satisfaction, quality of vision, and quality of life after bilateral LASIK surgery. Subjects will be assessed up to 3 months post-operatively. Clinical evaluations will include refractive outcomes, visual acuity, and administration of the adapted PROWL and the Quality-of-Life Impact of Refractive Correction (QIRC) Questionnaire.

Gender: All

Ages: 18 Years - 39 Years

Updated: 2025-09-15

1 state

Myopia
Astigmatism
ACTIVE NOT RECRUITING

NCT06571773

Evaluation of Toric Intraocular Lens(IOL) Combined With Capsular Tension Ring(CTR) in Patients With Cataract Combined With High Myopia

The objective of this study is to evaluate the postoperative visual quality and IOL stability in patients with cataracts and high myopia who have undergone surgery using astigmatism-correcting IOLs in conjunction with tension rings.It is a non-randomised retroprospective cohort study. Patients with high axial myopia (AL ≥ 26 mm) who underwent cataract phacoemulsification combined with toric IOL(Acrysof SN6ATY IQ toric IOL, Alcon, Alcon Laboratories, Fort Worth, Texas, USA) implantation from October 2020 to September 2023 at the Shanghai Tenth People's Hospital are selected. According to the usage of CTR, all patients will be divided into CTR group and control group, with a minimum follow-up of 3 months.Each patient underwent a comprehensive preoperative examination and ophthalmological examinations at the outpatient clinic 1 day, 1 week, 1 month, and 3 months postoperatively.Statistical analysis will be conducted using SPSS 26.0 statistical software.

Gender: All

Ages: 18 Years - 100 Years

Updated: 2025-08-28

1 state

Cataract
Astigmatism
Intraocular Lens Rotation
RECRUITING

NCT06902584

North American Comfilcon A Clinical Study

The main objective of this study is to demonstrate acceptable safety and effectiveness (performance) of comfilcon A Sphere, Toric, Multifocal, Toric Multifocal and Energys lenses, when used in the general population.

Gender: All

Ages: 8 Years - 75 Years

Updated: 2025-08-27

4 states

Astigmatism
Presbyopia
Ametropia
ACTIVE NOT RECRUITING

NCT07128316

LASIK Using Contoura With Phorcides vs. iDesign

Participants will undergo LASIK using Contoura with Phorcides calculation on one eye and LASIK using iDesign calculation on the contralateral eye to correct myopia.

Gender: All

Ages: 21 Years - 50 Years

Updated: 2025-08-18

1 state

Myopia
Astigmatism
ACTIVE NOT RECRUITING

NCT07126756

LASIK iDesign vs SMILE

The study will compare the 6-month visual outcomes (i.e., visual acuity, contract sensitivity, higher order aberrations), quality of vision (i.e., double vision, glare, starburst, halos, etc.) and dry eye symptoms of patients undergoing contralateral LASIK using iDesign and SMILE surgery.

Gender: All

Ages: 21 Years - 50 Years

Updated: 2025-08-17

1 state

Myopia
Astigmatism
ACTIVE NOT RECRUITING

NCT05796453

Post Market Clinical Follow-up (PMCF) Study of Clareon Vivity & Clareon PanOptix

The purpose of this Post-Market Clinical Follow-up study is to describe the long-term safety and performance of the Clareon Vivity and Vivity Toric and Clareon PanOptix and PanOptix Toric IOLs.

Gender: All

Ages: 18 Years - Any

Updated: 2025-08-14

6 states

Aphakia
Astigmatism
Presbyopia
RECRUITING

NCT07046065

Algorithm-assisted Subjective Refraction Program Dedicated to Children

Current refraction assessment in children is dependent on the Eye Care Specialist and lacks standardization. Essilor has developed new algorithm assisted subjective refraction software dedicated to children of 6-12 years old and suitable for use with Vision-S™ and Vision-R™ phoropters, in addition to existing software. Two different versions of the software have been developed: the first incorporating only the steps needed to perform an entire subjective refraction process (vA), and the second, identical to the first but incorporating additional steps useful for managing the child's attention and cooperation (vB). The software performance in terms of subjective refraction results will be compared to a conventional subjective refraction method performed with the Vision-R™700 phoropter in manual mode.

Gender: All

Ages: 6 Years - 12 Years

Updated: 2025-07-01

Refractive Assessment
Refractive Disorders
Hyperopia and Myopia
+3
ENROLLING BY INVITATION

NCT07007897

Observational Study - TA- 2025-1

This multi-centric, prospective observational study collects biometric datasets as well as associated video recordings of the surgical procedure.

Gender: All

Ages: 21 Years - Any

Updated: 2025-06-06

2 states

Astigmatism
RECRUITING

NCT06477081

KLEx Versus FS-LASIK for the Treatment of Myopia and Compound Myopic Astigmatism

FemtoLASIK is a type of laser eye surgery used to correct vision problems such as nearsightedness, farsightedness, and astigmatism. It involves two main steps: creating a flap and reshaping the cornea. Refractive lenticule extraction, (KLEx) is another laser eye surgery method to correct vision issues, which involves creating and extracting a lenticule without the need of a flap. The investigators will evaluate and compare the efficacy and safety of these two procedures.

Gender: All

Ages: 21 Years - Any

Updated: 2025-06-03

Myopia
Astigmatism
Myopic Astigmatism
RECRUITING

NCT03803852

Rotation of Hydrophobic Acrylic Lenses - Rayner RA0800C & Alcon Clareon & Hoya Nanex & Hoya Vivinex XY1-EM & RayOne EMV Toric & PODEYE Toric

The investigational devices are approved intraocular lenses (IOL) intended to be implanted after phacoemulsification in individuals suffering from age-related cataract with the need of cataract surgery. Within the study, three different IOLs will be investigated and separately evaluated. Cataract surgery with IOL implantation will be performed in subjects who have signed an informed consent form. Postoperative examinations will be postoperative refraction, visual acuity, slitlamp examination, and rotation of the IOL within 1 hour, 1 week, 1 month and 4-7 months. In the Alcon Clareon toric, RayOne EMV toric and PODEYE Toric group, patients receive a toric IOL according to their preoperative astigmatism

Gender: All

Ages: 45 Years - 95 Years

Updated: 2025-05-14

1 state

Age Related Cataracts
Astigmatism
NOT YET RECRUITING

NCT06896357

Effectiveness and Safety of Limbal Relaxing Incisions for Correcting Post Phacoemulsification High Astigmatism

To compare the effect of Limbal relaxing incisions (LRIs) plus spectacle correction versus spectacle correction alone on subjective and objective improvement in visual function for correcting post phacoemulsification high astigmatism .

Gender: All

Ages: 18 Years - Any

Updated: 2025-03-26

Astigmatism
Phacoemulsification
ACTIVE NOT RECRUITING

NCT06775509

Optical Quality of the Cornea in Orthokeratology

Analyzing Optical Quality After the Use of Overnight Orthokeratology (Ortho-K)

Gender: All

Ages: 12 Years - 21 Years

Updated: 2025-01-15

Myopia (Disorder)
Astigmatism
RECRUITING

NCT06694051

Application of Phototherapeutic Keratectomy Mode to Mark the Axis of Astigmatism

Corneal refractive surgery is an effective way to correct refractive error. Modern corneal refractive surgery for the correction of myopia or hyperopia can achieve or close to the expected goal, but to eliminate astigmatism is always one of the major problems of corneal refractive surgery. The key point in the correction of astigmatism is that as a vector parameter, astigmatism has both magnitude and direction. The angle error may be caused by the rotation of the patient's head position and the involuntary rotation of eyes. Phototherapeutic keratectomy can precisely cut the corneal tissue, and is often used in clinic to remove corneal scars or repair corneal surface morphology. In this study, the excimer laser therapeutic keratectomy mode was used to achieve accurate marking of the axis of astigmatism by setting the treatment laser parameters. With the help of the static cyclotorsion of the eye, the precise treatment of astigmatism could realize.

Gender: All

Ages: 18 Years - Any

Updated: 2024-11-19

1 state

Astigmatism