Clinical trial NCT06492538: Biometric Changes After Intervention of Anterior Chamber Angle : an Observational Study
Official title: Biometric Changes After Intervention of Anterior Chamber Angle : an Observational Study
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Angle-closure Glaucoma
Minimally Invasive Glaucoma Surgery
Goniosynechialysis
Goniotomy
Glaucoma
Lead sponsor: Zhongshan Ophthalmic Center, Sun Yat-sen University
Sponsor class: OTHER
First posted: 2024-07-09
Enrollment: 300
Sex: ALL
Minimum age (years): 30
Maximum age (years): 85
Standard ages: ADULT
OLDER_ADULT
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients diagnosed with glaucoma typically present with: IOP \> 21 mmHg with or without the use of ocular hypotensive medications; (3) with obvious glaucomatous optic neuropathy \[cup-to-disc (C/D) ratio ≥ 0.7, C/D ratio asymmetry \> 0.2, or rim width at the superotemporal and inferotemporal \< 0.1 vertical diameter of the optic disc\], and glaucomatous visual field defects, such as nasal step, arcuate scotoma, and paracentral scotoma;

Brief summary: The drainage angle in the anterior chamber of the eye mediates the outflow of aqueous humor, and pathological changes here can lead to high intraocular pressure and glaucoma. Minimally invasive glaucoma surgery, particularly angle surgery, has advanced recently, allowing clear visualization of angle structures like the trabecular meshwork and Schlemm's canal using surgical goniolens. Techniques for angle intervention include widening the angle, reopening closed angles, and rebuilding outflow pathways using methods such as laser peripheral iridotomy, Argon laser peripheral iridoplasty, and mechanical separation of adhered tissues. Our research team plans to conduct imaging studies to track the healing of angle tissues post-surgery, aiming to support innovation and standardization of minimally invasive angle surgery.

Detailed description: Pathological elevated intraocular pressure is one of the most important disease characteristics of glaucoma. Blockage of aqueous humor outflow within the eye is the primary cause of high intraocular pressure. The drainage angle in the anterior chamber of the eye mediates the outflow of aqueous humor. Pathological changes in this area can lead to the development of high intraocular pressure and glaucoma, such as primary angle closure glaucoma (PACG) caused by angle closure. Minimally invasive glaucoma surgery has rapidly developed in recent years, with angle surgery being a major branch. With the use of surgical goniolens, structures within the angle, such as trabecular meshwork and Schlemm's canal, can be visualized clearly during surgery. Methods for angle intervention include but not limit ed to widening the peripheral anterior chamber angle, reopening adhered or appositionally closed angles, and rebuilt outflow pathways by incising diseased areas to increase aqueous humor outflow. Techniques include laser peripheral iridotomy (LPI) to relieve pupillary block and deepen the peripheral anterior chamber, Argon laser peripheral iridoplasty (ALPIP) to stimulate iris contraction and widen the angle, and mechanical separation of adhered angle tissues using instruments like goniosynechialysis hooks or iris repositors. Surgical incision using instruments such as Microhook, trabeculectomy hooks, or cannulas can be performed to remove the diseased inner wall of Schlemm's canal and the diseased trabecular meshwork either partially or circumferentially. However, the healing and outcomes of angle tissues following invasive angle interventions, and their impact on surgical outcomes, remain unclear. Therefore, our research team proposes to conduct imaging observation studies to track, observe, and quantify the status of the angle, exploring the healing process of angle tissues. This aims to provide theoretical support for the innovation and standardization of minimally invasive angle surgery.

Eligibility criteria: Inclusion Criteria:

* Glaucoma patients eligible for standalone or combined angle intervention surgeries, such as LPI, LPIP, goniosynechialysis, trabeculotomy alone or combined with surgical iridectomy or phacoemulsification and intraocular lens implantation;
* Patients capable of undergoing preoperative examinations including CASIA2-OCT (anterior segment OCT), UBM, slit-lamp gonioscopy, IOL Master (or other optical biometry);
* Patients willing to participate in this study, signing informed consent, and agreeing to follow-up according to the study protocol.

Exclusion Criteria:

* Patients with severe ocular conditions such as corneal infection, ulcer, trauma, ocular tumors, retinal vascular occlusion, and retinal detachment;
* Those with various types of eye diseases that affect ocular parameter acquisition or interfere with visual field examination;
* Long-term local or systemic use of glucocorticoids;
* Patients with severe systemic diseases;
* Pregnant or lactating women;
* Unable to complete 12-month postoperative follow-up.

Primary outcomes:
measure: Changes in biological parameters of the anterior chamber angle
timeFrame: 12 months
Secondary outcomes:
measure: success rate of angle intervention surgeries
timeFrame: 12 months
Other outcomes:
measure: safety of angle intervention surgeries
timeFrame: 1 months
Locations:
city: Guangzhou
country: China
facility: Zhongshan ophthalmic center
state: Guangdong
Study officials:
affiliation: State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University
name: Xinbo Gao, MD
role: PRINCIPAL_INVESTIGATOR
References: