Night and low-contrast vision with three types of intraocular lenses

Clinical Evaluation of Low Contrast Defocus Curves, Low Light Photic Phenomena, and Dysphotopsia Profiles in Pseudophakic Patients

Observational Empire Eye and Laser Center · NCT07213167

This study will test how three different intraocular lenses affect night vision, low-contrast vision, and related symptoms in people who had cataract surgery.

Quick facts

Study typeObservational
Enrollment120 (estimated)
Ages22 Years and up
SexAll
SponsorEmpire Eye and Laser Center Academic / other
Locations1 site (Bakersfield, California)
Trial IDNCT07213167 on ClinicalTrials.gov

What this trial studies

This observational study compares visual function and nighttime photic phenomena across three commonly used intraocular lens (IOL) models using device-based tests and patient questionnaires. Participants complete two vision questionnaires (PRVSQ v2 and AIOLIS in randomized order) and undergo a battery of tests including low- and high-contrast defocus curves, halometry at multiple light levels and colors, contrast sensitivity, pupilometry, and standard acuity and slit-lamp exams. Primary endpoints are the 50% low-contrast defocus curve, objective halometry measurements under cool white light, and PRVSQv2 results, with secondary outcomes covering a wide set of visual performance and satisfaction measures. The study enrolls adults at least three months after bilateral IOL implantation and aims to correlate objective device measures with patient-reported symptoms.

Who should consider this trial

Good fit: Ideal candidates are adults (≥22 years) who are bilaterally pseudophakic at least three months after IOL implantation, can complete vision testing, and can read and respond in English.

Not a fit: People with uncorrected distance visual acuity worse than 20/25, significant pupil abnormalities, unstable fixation (for example nystagmus), prior corneal refractive surgery, or who cannot complete the tests are unlikely to benefit from this study.

Why it matters

Potential benefit: If successful, the results could help doctors and patients choose IOLs that provide better night and low-contrast vision and reduce bothersome visual symptoms.

How similar studies have performed: Other observational comparisons of IOL performance and the use of halometry have been reported, but the combined correlation of low-contrast defocus curves, multicolor halometry, and detailed patient-reported dysphotopsia profiles is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Minimum 22 years of age
* Bilateral pseudophakia, at least 3 months postoperative from IOL implantation, with one of the study IOL models in at least one eye.
* Availability, willingness, and sufficient cognitive awareness to comply with examination procedures
* Signed informed consent and HIPAA authorization or equivalent documentation necessary to comply with applicable privacy laws pertaining to medical treatment in the governing countries
* Ability to understand and respond to a questionnaire in English

Exclusion Criteria:

* Any clinically significant pupil abnormalities (non-reactive, fixed pupils, or abnormally shaped pupils.
* Inability to focus or fixate for prolonged periods of time (e.g., due to strabismus, nystagmus, etc.)
* Uncorrected distance visual acuity worse than 20/25 in either eye
* Prior corneal refractive surgery (LASIK, LASEK, RK, PRK, etc.) or intraocular surgery. Note: Prophylactic peripheral iridotomies and peripheral laser retinal repairs that, in the opinion of the investigator will not confound study outcomes are acceptable.
* Posterior capsular opacification with grading worse than 1+
* Ocular findings that may, in the opinion of the investigator, affect vision and/or contrast sensitivity

Where this trial is running

Bakersfield, California

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions DysphotopsiaPosterior Capsule OpacificationVisual AcuityVisual FunctionContrast SensitivityHalometryManifold Vision MeterPRVSQ
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.