Phacoemulsification and Goniosynechialysis With or Without Kahook Dual Blade Goniotomy in Chronic Primary Angle-Closure Glaucoma: A 1-Year Randomized Controlled Trial
Phase: NA
Conditions: Primary Angle-closure Glaucoma
Sponsor: Peking University People's Hospital

Efficacy and Safety of Phacoemulsification and Goniosynechialysis 
With or Without Kahook Dual Blade Goniotomy in Chronic Primary 
Angle-Closure Glaucoma: A 1-Year Randomized Controlled Trial 
Date：Feb 28 2024 
Brief Summary Primary angle-closure glaucoma is a major cause of 
irreversible blindness. For patients with chronic primary angle-
closure glaucoma and cataracts, the standard surgery is 
phacoemulsification and goniosynechialysis. This surgery deepens the 
anterior chamber and opens the angle. But it does not fix the damaged 
trabecular meshwork. Many patients still have high eye pressure after 
this standard surgery. The Kahook Dual Blade is a microinvasive 
device. It cuts and removes the diseased trabecular meshwork. This 
trial compares the 1-year results of standard surgery alone versus 
standard surgery with the Kahook Dual Blade. The study will measure 
eye pressure control, medication use, and safety. 
Detailed Description Patients with chronic primary angle-closure 
glaucoma experience prolonged high intraocular pressure and long-term 
peripheral anterior synechiae. This chronic condition causes 
irreversible damage to the trabecular meshwork. Standard 
phacoemulsification and goniosynechialysis successfully separate the 
synechiae and open the angle. But the microscopic drainage filter 
remains blocked. Because the physiological resistance is not fixed, 
many patients have poor postoperative intraocular pressure control. 
They also face risks of delayed pressure spikes and synechiae 
recurrence. 
The Kahook Dual Blade is designed to precisely cut a strip of 
diseased trabecular meshwork and the inner wall of Schlemm’s canal. 
Removing this blocked tissue allows aqueous humor to flow directly 
into the collector channels. We lack high-quality prospective 
randomized controlled trials to compare this combined procedure 
against the traditional approach. 
This prospective, single-center, randomized controlled trial takes 
place at Peking University People’s Hospital. The study will 
randomly assign 68 patients to receive either standard surgery alone 
or standard surgery combined with the Kahook Dual Blade. The primary 
goal is to compare the 1-year efficacy and safety of the two 
treatments. The study also uses ultrasound biomicroscopy to group 
patients by specific angle-closure mechanisms. These mechanisms 
include pupillary block, plateau iris, and lens-induced types. The 

researchers will evaluate how these different mechanisms affect the 
surgical outcomes. 
Study Design 
• 
Study Type: Interventional (Clinical Trial) 
• 
Allocation: Randomized 
• 
Intervention Model: Parallel Assignment 
• 
Masking: Single Blind (Outcomes Assessor) 
• 
Primary Purpose: Treatment 
Arms and Interventions 
• 
Active Comparator: PEI-GSL Group 
o Intervention: Procedure: Phacoemulsification with 
intraocular lens implantation combined with 
goniosynechialysis. A blunt instrument mechanically 
separates the peripheral anterior synechiae from the 
trabecular meshwork. 
• 
Experimental: PEI-GSL-KDB Group 
o Intervention: Procedure: Phacoemulsification and 
goniosynechialysis combined with Kahook Dual Blade 
goniotomy. The Kahook Dual Blade excises approximately 4 
clock hours (120°) of the diseased trabecular meshwork 
in the nasal quadrant. 
Primary Outcome Measures 
1. Mean Intraocular Pressure (IOP) [Time Frame: Baseline, Day 1, 
Week 1, Month 1, Month 3, Month 6, Month 12] 
2. Magnitude of IOP Reduction [Time Frame: 12 months] (Absolute 
and percentage reduction from baseline). 
3. Cumulative Surgical Success Rate [Time Frame: 12 months] 
(Defined as postoperative IOP ≤ 21 mmHg and IOP reduction ≥ 
20% from baseline, without glaucoma reoperation). 
Secondary Outcome Measures 
1. Change in Number of IOP-Lowering Medications [Time Frame: 
Baseline to 12 months] 
2. Incidence of Adverse Events [Time Frame: Up to 12 months] 
(Includes intraoperative posterior capsular rupture, 
postoperative hyphema, and transient IOP spikes). 

3. Extent of Peripheral Anterior Synechiae (PAS) [Time Frame: 
Baseline, 6 months, 12 months] (Measured in clock hours using 
gonioscopy and anterior segment imaging). 
Eligibility Criteria 
• 
Ages Eligible for Study: 40 Years and older 
• 
Sexes Eligible for Study: All 
• 
Inclusion Criteria: 
o Confirmed diagnosis of chronic primary angle-closure 
glaucoma (PAS ≥ 180° on indentation gonioscopy, 
glaucomatous optic neuropathy, and visual field defects). 
o Visually significant cataract requiring 
phacoemulsification. 
o Inadequately controlled intraocular pressure (IOP > 21 
mmHg despite maximum medications, or IOP ≤ 21 mmHg 
dependent on two or more topical medications). 
• 
Exclusion Criteria: 
o Secondary angle-closure glaucoma (e.g., neovascular, 
uveitic, or lens-induced). 
o History of prior intraocular surgery or incisional 
glaucoma procedures (previous uncomplicated laser 
peripheral iridotomy is allowed). 
o Concurrent severe ocular pathologies limiting visual 
prognosis (e.g., severe diabetic retinopathy, advanced 
macular degeneration). 
o Central corneal endothelial cell density < 1500 
cells/mm². 
o Severe systemic conditions preventing surgical tolerance 
or 1-year follow-up.