An observational study in Dysphotopsia, Posterior Capsule Opacification and Visual Acuity, sponsored by Dr. Daniel H. Chang, MD. Recruiting at 1 site in United States. Open to participants aged 22 Years and older. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by Dr. Daniel H. Chang, MD · Observational
The goal of this clinical investigation is to evaluate visual acuity and contrast sensitivity in low lighting conditions using several different testing devices, and measure nighttime side effects of intraocular lens (IOL) implants after cataract surgery.
Researchers will compare the results for three different types of IOLs to see how each lens contributes to overall visual function, patient experience and satisfaction.
Participants will:
The purpose of the study is to correlate the low contrast defocus curves, objective halometry measurement of low light photic phenomena, and patient reported dysphotopsia profiles of the various study IOLs.
The primary endpoints are low (50%) contrast defocus curve, halometry (cool white light) assessment of photic phenomena, and PRVSQv2 results.
The secondary endpoints are:
Participants will:
54 studies on the registry are indexed under Pseudophakia; 8 are open to participants now.
This study's planned enrollment of 120 is above the median of 71 across 26 observational studies indexed under Pseudophakia.
Browse Pseudophakia studies →Dr. Daniel H. Chang, MD is the lead sponsor of 2 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Bilateral pseudophakia, at least 3 months postoperative from IOL implantation with one of the study IOL models.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Pseudophakic subjects with Tecnis Monofocals, Models ZCB00, ZCUxxx, DIB00, GIB00, and DIUxxx intraocular lenses.
Other: None-placebo
Pseudophakic subjects with Tecnis Symfony Optiblue, model ZXR00V, ZXWxxx intraocular lenses.
Other: None-placebo
Pseudophakic subjects with Tecnis Odyssey, model DRN00V, DRTxxx intraocular lenses.
Other: None-placebo
No interventions, only post-market, post-implantation observation.
Low (50%) contrast defocus curve
Measured low (50%) contrast defocus curve compared between all three groups
Time frame: Day 1
Halometry assessment of photic phenomena
Halometry assessment of halos and starbursts utilizing a cool white light with varying intensities. Comparing the measured size of the ring (deg) of each condition between all three groups.
Time frame: Day 1
PRVSQv2 questionnaire results
PRVSQv2 questionnaire results compared between all three groups: Frequency and bother/severity of symptoms (scale 1 to 5, with 5 most bothersome)
Time frame: Day 1
Best corrected distance visual acuity (BCDVA)
Best corrected distance visual acuity (BCDVA) compared between all three groups
Time frame: Day 1
Low contrast (50%) BCDVA
Low contrast (50%) BCDVA compared between all three groups
Time frame: Day 1
Contrast Sensitivity
Contrast sensitivity compared between all three groups
Time frame: Day 1
High Contrast Defocus Curve
High Contrast Defocus Curve compared between all three groups
Time frame: Day 1
Halometry
Halometry assessment of halos and starbursts utilizing various light colors (cool white, warm white, red, yellow, and green) and intensities. Comparing the measured size of the ring (deg) of each condition between all three groups.
Time frame: Day 1
Patient-Reported Outcome (PRO) Questionnaires
PRVSQv2 and AIOLIS vision questionnaire results compared between all three groups. Frequency and bother/severity of symptoms (scale 1 to 5, with 5 most bothersome)
Time frame: Day 1
Pupil Size
Photopic and mesopic pupil size compared between all three study groups
Time frame: Day 1
YAG Capsulotomies
Number of YAG capsulotomies performed within one year post-op compared between all three groups
Time frame: Day 1
Posterior capsular opacification (PCO)
Pre-planned post-hoc analysis evaluating number of participants with and without PCO compared between all three groups
Time frame: Day 1
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Dr. Daniel H. Chang, MD