Trabeculectomy Versus Peripheral Iridectomy Plus Goniotomy in Advanced PACG (TVG)

Effectiveness and Safety of Trabeculectomy and Peripheral Iridectomy Plus Goniotomy in Advanced Primary Angle-closure Glaucoma: a Multicenter Non-inferiority Randomized Controlled Trial

A multicenter, parallel, open, non-inferior randomized controlled trial is conducted to compare the effectiveness and safety of trabeculectomy and peripheral iridectomy plus goniotomy (TVG) in the treatment of advanced primary angle closure glaucoma with no or mild cataracts.

Study Overview

• Status: Recruiting
• Conditions: Primary Angle Closure Glaucoma
• Intervention / Treatment: Procedure: Trabeculectomy; Procedure: SPI+GSL+GT

Detailed Description

Primary angle-closure glaucoma (PACG) has a high prevalence and blinding rate in China. The routine first-line treatment of advanced PACG is trabeculectomy, especially in those without cataract. However, due to surgery complications and exhausting post-surgery caring, traditional trabeculectomy is not an ideal choice in clinical practice, particularly in patients with high risk of complications such as younger age and shorter axial length. Peripheral iridectomy (SPI) plus intraocular pressure (IOP)-lowering medications is an alternative.

Minimally invasive glaucoma surgery (MIGS) has recently showed its safety and effectiveness in the treatment of PACG, usually combined with cataract surgery, goniosynechialysis (GSL) and goniotomy(GT). The safety and effectiveness of phacoemulsification and intraocular lens implantation (PEI)+GSL+GT in advanced PACG with cataract has been conducted (clinical trials.gov, NCT04878458). It is valuable to explore the safety and efficacy of SPI+GSL+GT in these PACG patients with no or mild cataracts.

Therefore, this study intends to conduct a multicenter, non-inferior randomized controlled clinical trial to compare the effectiveness and safety of trabeculectomy versus SPI+GSL+GT in advanced PACG with no or mild cataracts.

• Study Type: Interventional
• Enrollment (Anticipated): 88
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Xiulan Zhang, MD. PhD; Phone Number: +86 13570166308; Email: zhangxl2@mail.sysu.edu.cn
• Study Contact Backup: Name: Xinbo Gao, MD. PhD; Phone Number: +86 18319579657; Email: gaoxb@mail.sysu.edu.cn

Study Locations

• China
  • Guangdong
    • Guangzhou, Guangdong, China, 510060
      • Recruiting
      • Zhongshan Ophthalmic Center, Sun Yat-sen University
      • Contact: Xiulan Zhang, MD, PhD; Phone Number: +86 13059106657; Email: zhangxl2@mail.sysu.edu.cn
      • Contact: Xinbo Gao, MD, PhD; Phone Number: +86 18319579657; Email: gaoxb@mail.sysu.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 45 years to 80 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Age 45-80 years.

2. Eyes diagnosed with advanced PACG who meet following criteria a, b, and c; or a, b, and d:

   1. PAS: ≥180° range, including nasal and inferior quadrants;
   2. IOP >21 mmHg with or without anti-glaucoma medications (the medications include the maximally tolerated medications), taken with the Goldmann applanation tonometer;
   3. Glaucomatous optic neuropathy (cup-to-disc [C/D] ratio ≥0.7, C/D asymmetry >0.2, or rim width at the superior and inferior temporal areas <0.1 of the vertical diameters of the optic disc);
   4. Glaucomatous visual field defects (nasal step, arcuate scotoma, and paracentral scotoma on a reliable Humphrey analyzer and a mean deviation of ≤-12 dB).
3. No or mild cataracts and uncorrected visual acuity of ≥0.63 (Early Treatment Diabetic Retinopathy Study chart);
4. Axial length of ≥20 mm.

Exclusion Criteria:

1. History of ocular surgery or trauma.
2. Retinal disease that influences the collection of ocular parameters or other types of glaucoma, including open-angle glaucoma, secondary angle-closure glaucoma, steroidal glaucoma, angle recession glaucoma, neovascular glaucoma, nanophthalmos, and pseudoexfoliation syndrome.
3. Monophthalmia (best-corrected visual acuity of <0.01 in the non-study eye).
4. An International Standardized Ratio of >3.0, for patients receiving warfarin or anticoagulant therapy before surgery.
5. Patients with serious systemic diseases.
6. Pregnant or lactating women.

If both eyes are eligible for the study, the eye with the worse visual field or optic nerve will be included.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Trabeculectomy; Forty-four patients with advanced primary angle closure glaucoma will receive trabeculectomy.	Procedure: Trabeculectomy; trabeculectomy
EXPERIMENTAL: SPI+GSL+GT; Forty-four patients with advanced primary angle closure glaucoma will receive surgical peripheral iridectomy (SPI) combined with goniosynechialysis (GSL) and goniotomy (GT).	Procedure: SPI+GSL+GT; Peripheral iridectomy (SPI) combined with goniosynechialysis (GSL) and goniotomy (GT)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Intraocular pressure at postoperative 12 months	Intraocular pressure after surgery using Goldmann or non-contact tonometer.	Postoperative 12 month

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Cumulative success rate of surgery	Cumulative success rate of surgery is defined as : (i) Complete success is defined as the postoperative intraocular pressure between 5 and 18 mmHg, and 20% reduction from baseline without anti-glaucoma medications. (ii) Qualified success is defined as the postoperative intraocular pressure between 5 and 18 mmHg, and 20% reduction from baseline with anti-glaucoma medications.	Postoperative 12, 24, 36 months
Intraoperative and postoperative complications	Intraoperative and postoperative complications, such as shallow anterior chamber, malignant glaucoma, hyphema, persistent hypotony, corneal endothelium decompensation, endophthalmitis, and bleb-related complications.	Postoperative 0, 1, 7 days, and 1, 3, 6, 12, 18, 24, 30, 36 months
The numbers of anti-glaucoma medications	Numbers of anti-glaucoma medications.	Postoperative 0, 1, 7 days, and 1, 3, 6, 12, 18, 24, 30, 36 months

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual acuity	Uncorrected and best corrected visual acuity will be documented using ETDRS chart.	Postoperative 0, 1, 7 days, and 1, 3, 6, 12, 18, 24, 30, 36 months
The degree of peripheral anterior synechia	The peripheral anterior synechia is checked using gonioscopy. Range from 0-360° will be documented.	Postoperative 0, 3, 12, 24, 36 months
Corneal endothelial cell counting	Corneal endothelial cell counting will be documented using specular microscope.	Postoperative 0,12, 24, 36 months
Visual field	Visual field will be performed using Humphrey analyzer, in which parameters of mean deviation (MD), pattern standard deviation (PSD) will be documented.	Postoperative 0,6,12, 24, 36 months
Optic nerve head morphology	Optic nerve head morphology will be derived from optical coherence tomography (Cirrus 5000, Carl Zeiss Meditec, USA or Heidelberg OCT, SPECTRALIS OCT, Heidelberg, Germany).	Postoperative 0,12, 24, 36 months
Retinal thickness	Retinal thickness will be derived from optical coherence tomography (Cirrus 5000, Carl Zeiss Meditec, USA or Heidelberg OCT, SPECTRALIS OCT, Heidelberg, Germany).	Postoperative 0,12, 24, 36 months
The quality of life	Quality of life will be measured with EQ-5D-5L questionnaire.	Postoperative 0,12, 24, 36 months
Filtering bleb classification	Filtering bleb classification using the Indiana Bleb Appearance Grading Scale, including height, width, extent, vascularity, and Seidel test.	Postoperative 3, 12, 24, 36 months
Surgical time	Surgical time will be documented.	Postoperative 1 day
Surgical cost	Surgical cost will be documented.	Postoperative 1 day

Collaborators and Investigators

• Sponsor: Sun Yat-sen University
• Collaborators: West China Hospital; Chongqing Medical University; The Second Affiliated Hospital of Harbin Medical University; First Hospital of Shijiazhuang City; People's Hospital of Chongqing; Handan City Eye Hospital
• Investigators: Principal Investigator: Xiulan Zhang, MD. PhD, Zhongshan Ophthalmic Center, Sun Yat-sen University

Publications and helpful links

General Publications

• Husain R, Do T, Lai J, Kitnarong N, Nongpiur ME, Perera SA, Ho CL, Lim SK, Aung T. Efficacy of Phacoemulsification Alone vs Phacoemulsification With Goniosynechialysis in Patients With Primary Angle-Closure Disease: A Randomized Clinical Trial. JAMA Ophthalmol. 2019 Oct 1;137(10):1107-1113. doi: 10.1001/jamaophthalmol.2019.2493.
• Barry M, Alahmadi MW, Alahmadi M, AlMuzaini A, AlMohammadi M. The Safety of the Kahook Dual Blade in the Surgical Treatment of Glaucoma. Cureus. 2020 Jan 16;12(1):e6682. doi: 10.7759/cureus.6682.
• Tanito M, Sugihara K, Tsutsui A, Hara K, Manabe K, Matsuoka Y. Midterm Results of Microhook ab Interno Trabeculotomy in Initial 560 Eyes with Glaucoma. J Clin Med. 2021 Feb 17;10(4):814. doi: 10.3390/jcm10040814.
• Grover DS, Smith O, Fellman RL, Godfrey DG, Gupta A, Montes de Oca I, Feuer WJ. Gonioscopy-assisted Transluminal Trabeculotomy: An Ab Interno Circumferential Trabeculotomy: 24 Months Follow-up. J Glaucoma. 2018 May;27(5):393-401. doi: 10.1097/IJG.0000000000000956.
• Dorairaj S, Tam MD, Balasubramani GK. Two-Year Clinical Outcomes of Combined Phacoemulsification, Goniosynechialysis, and Excisional Goniotomy For Angle-Closure Glaucoma. Asia Pac J Ophthalmol (Phila). 2020 Oct 6;10(2):183-187. doi: 10.1097/APO.0000000000000321.
• Tham CC, Kwong YY, Baig N, Leung DY, Li FC, Lam DS. Phacoemulsification versus trabeculectomy in medically uncontrolled chronic angle-closure glaucoma without cataract. Ophthalmology. 2013 Jan;120(1):62-7. doi: 10.1016/j.ophtha.2012.07.021. Epub 2012 Sep 15.
• Gedde SJ, Feuer WJ, Lim KS, Barton K, Goyal S, Ahmed IIK, Brandt JD; Primary Tube Versus Trabeculectomy Study Group. Treatment Outcomes in the Primary Tube Versus Trabeculectomy Study after 3 Years of Follow-up. Ophthalmology. 2020 Mar;127(3):333-345. doi: 10.1016/j.ophtha.2019.10.002. Epub 2019 Oct 9.
• Gao X, Lv A, Lin F, Lu P, Zhang Y, Song W, Zhu X, Zhang H, Liao M, Song Y, Hu K, Zhang Y, Peng Y, Tang L, Yuan H, Xie L, Tang G, Nie X, Jin L, Fan S, Zhang X; TVG study group. Efficacy and safety of trabeculectomy versus peripheral iridectomy plus goniotomy in advanced primary angle-closure glaucoma: study protocol for a multicentre, non-inferiority, randomised controlled trial (the TVG study). BMJ Open. 2022 Jul 4;12(7):e062441. doi: 10.1136/bmjopen-2022-062441.

Study record dates

Study Major Dates

• Study Start (ACTUAL): January 5, 2022
• Primary Completion (ANTICIPATED): June 30, 2024
• Study Completion (ANTICIPATED): June 30, 2026

Study Registration Dates

• First Submitted: November 25, 2021
• First Submitted That Met QC Criteria: December 4, 2021
• First Posted (ACTUAL): December 20, 2021

Study Record Updates

• Last Update Posted (ACTUAL): June 14, 2022
• Last Update Submitted That Met QC Criteria: June 9, 2022
• Last Verified: June 1, 2022

More Information

Terms related to this study

• Keywords: glaucoma; angle closure
• Additional Relevant MeSH Terms: Eye Diseases; Ocular Hypertension; Glaucoma; Glaucoma, Angle-Closure
• Other Study ID Numbers: 2021KYPJ191

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No