An observational study in Primary Angle-Closure Glaucoma, sponsored by Peking University People's Hospital. Not yet recruiting. Per ClinicalTrials.gov, last updated 2026-04-24.
Sponsored by Peking University People's Hospital · Observational
Primary angle-closure disease (PACD) is a major cause of vision loss, often treated with a combined surgery that removes the eye's natural lens (cataract surgery) and physically opens the eye's drainage system (goniosynechialysis). While effective, this surgery carries a small risk of a severe complication called ciliary block (or aqueous misdirection), where fluid builds up in the wrong part of the eye, pushing structures forward and causing high eye pressure. Recently, doctors have also noticed a "partial" form of this block, which can slowly cause the eye's drainage angle to close again without immediate severe symptoms.
The purpose of this prospective, observational study is to identify which patients are at the highest risk for developing classic or partial ciliary block after this combined surgery. Researchers will use standard, non-invasive eye imaging tools-such as ultrasound biomicroscopy (UBM) and optical coherence tomography (OCT)-to take highly detailed measurements of the front of the eye before surgery. They will specifically look at factors like the width of the anterior chamber, the thickness of the lens, and the eye's overall length. To ensure accuracy, patients with a very short eye length (less than 19mm) will not be included in the study.
Because this is an observational study, participation will not change a patient's standard surgical plan. Patients will undergo their scheduled surgery and be monitored for 12 months during routine follow-up visits to track their eye pressure, vision, and any structural changes in the eye.
By confirming which pre-surgery measurements predict ciliary block, researchers hope to validate a risk-warning model. This will help eye surgeons take preventive steps-such as administering specific medications like mannitol before surgery-to make the procedure safer and improve long-term outcomes for patients with PACD.
91 studies on the registry are indexed under Glaucoma, Angle-Closure; 17 are open to participants now.
This study's planned enrollment of 1,150 is above the median of 225 across 32 observational studies indexed under Glaucoma, Angle-Closure.
Browse Glaucoma, Angle-Closure studies →Peking University People's Hospital is the lead sponsor of 609 studies on the registry; 247 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Patients with Primary Angle-Closure Disease (PACD)-spanning PACS, PAC, and PACG-who require surgical intervention with phacoemulsification combined with goniosynechialysis. Participants will be enrolled from the routine clinical care settings across multiple participating tertiary ophthalmic centers.
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.
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.
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.
Patients who develop classic or partial ciliary block (CB) during the 12-month follow-up period after phacoemulsification combined with goniosynechialysis.
Patients who do not develop any form of ciliary block during the 12-month follow-up period after the surgery.
Incidence of Ciliary Block (Classic and Partial)
The primary outcome is the occurrence rate of classic or partial ciliary block (CB) following phacoemulsification combined with goniosynechialysis. Classic CB is diagnosed by a shallow or flat anterior chamber with elevated intraocular pressure, excluding pupillary block or choroidal effusion. Partial (subclinical) CB is defined by meeting at least two of the following criteria: an unexpected shallow anterior chamber (e.g., less than the expected 3mm or significantly smaller than the contralateral eye), a significant myopic shift (≥ -1.50D) indicating IOL-iris diaphragm anterior shift, UBM/OCT evidence of ciliary body anterior rotation, or significant deepening of the anterior chamber after cycloplegic administration. Intraoperative aqueous misdirection is also recorded as a primary endpoint event.
Time frame: Up to 12 months postoperatively
No study locations are listed for this record.
Start is estimated for Apr 2026; primary completion for Apr 2030, 47 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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