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Laser Peripheral Iridotomy Plus Laser Peripheral Iridoplasty for Primary Angle Closure

Primary Purpose

Glaucoma, Angle-Closure

Status
Unknown status
Phase
Not Applicable
Locations
China
Study Type
Interventional
Intervention
neodymium:yttrium-aluminum- garnet laser
frequency-doubled Q-switched neodymium:yttrium-aluminum-garnet 532-nm laser
Pilocarpine
LPIP plus LPI
Proparacaine
LPI
Sponsored by
Sun Yat-sen University
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Glaucoma, Angle-Closure

Eligibility Criteria

40 Years - 75 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  1. Clinical diagnosis of primary angle closure (PAC), with IOP≤30mmHg and PAS≤270°.
  2. PAC with multi-mechanism based on UBM examination (multi-mechanism is defined as primary angle closure is caused by pupil block plus at least one kind of non-pupil block factors like (relative anterior position and thick of the ciliary body, the big volume of the iris, the anterior location of the iris insertion into the ciliary body)or any two or more kinds of combination.
  3. Visual acuity≥ 20/40
  4. Age between 40-75 years old Chinese people

If both eyes of a patient are eligible for the study, the e eye had worse visual acuity will be selected. Only one eye per patient is eligible for the study.

Drug washout:

Eligible patients who are already on anti-glaucoma medications are required to have drug washout before being randomized. Various medications have different washout periods: Prostaglandin analogues 4 weeks, Beta blockers 3 weeks, Adrenergic agonist 2 weeks, Cholinergic agonist 5 days, Carbonic Anhydrase Inhibitors 5 days. Patients whose IOP>30 mm Hg during this washout period will be stopped from further washout and be withdrawn from the study.

Exclusion Criteria:

  1. Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits.
  2. Angle closure due to secondary causes (subluxed lens, neovascular, uveitic, traumatic, post-operative)
  3. Previous incisional intraocular surgery or ocular laser in study eye (LPI or LPIP, cyclodestructive procedure, cataract surgery)
  4. Primary angle closure with glaucomatous neuropathy.
  5. Have cataract in the studying eye and anticipated to have cataract surgery in the coming 3 years; the existing cataract affect visual field examination and fundus examination; the visual acuity <20/40 due to the existing cataract.
  6. Who are using IOP lowing drugs and do not have drug washout
  7. Need for glaucoma surgery combined with other ocular procedures (i.e. cataract surgery, penetrating keratoplasty, or retinal surgery) or anticipated need for urgent additional ocular surgery
  8. Coexisting other ocular diseases (i.e. cornea abnormal or cornea infection, Iridocorneal endothelial syndrome or anterior segment dysgenesis, nanophthalmos, high myopia (>6.0D), Chronic or recurrent uveitis, ocular cancer, trauma, central retinal vein occlusion, central retinal artery occlusion, retinal detachment)
  9. cornea endothelium counting <1000/mm2
  10. need local or systemic steroid long-term use
  11. Unwilling to discontinue contact lens use after surgery
  12. Who are taking parting in other drug clinical trials
  13. Pregnant or nursing women
  14. Severe systemic disease (i.e. diabetes mellitus, hypertension, the end stage of cardiac disease, nephropathy disease, respiratory disease and cancer.
  15. Allergic to pilocarpine or alcaine
  16. Contraindication to ocular laser diseases.

Sites / Locations

  • Zhongshan Ophthalmic CenterRecruiting

Arms of the Study

Arm 1

Arm 2

Arm Type

Active Comparator

Experimental

Arm Label

single LPI

LPIP plus LPI

Arm Description

LPI was performed with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia will be administered. The treatment site was selected in the superior nasal iris or in a crypt, where present. Treatment was initiated with a pulse of 3-5mJ, the power was increased until patency was achieved, the opening of iris >0.1mm. and patency was determined by direct visualization of the posterior chamber.

LPIP was applied with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia will be administered. Twenty to 30 spots of 250-300 mW power with 300-500 microns of size and duration of 400-500 ms were applied. Power was modified arbitrarily until an effective iris contraction was obtained. Effective iris contraction was considered as a concentric movement around the laser spot, with minimal iris pigmentation and immediate angle opening observed through the lens mirrors using a Goldmann lens. Power was lowered if there was any bursting sound perceived, pigment dispersion, air bubbles or considerable pain. LPI was performed after LPIP procedure

Outcomes

Primary Outcome Measures

Progression rate determined by number of patients who progress after laser treatment for each group.
PAC progression defined as presence of any of the following: Acute angle closure crisis Intraocular (IOP) was 8mmHg higher than initiation 1 month after the laser procedure IOP was ≥22mmHg when measured three times of continuous 1 month after the lase procedure The progression of peripheral anterior synechiae ≥ 1 clock hour within 3 years after the laser procedure as measured by gonioscopic examination. glaucomatous neuropathy within 3 years after the laser procedure

Secondary Outcome Measures

Additional medication or surgery required questionnaire
the medication required to control the IOP the additional surgery required to control the progression of the PAC
The change of the best corrected visual acuity after the laser procedure
The number of the cornea endothelial cells
The change in angle width and configuration as measured by ultrasound biomicroscopy (UBM)

Full Information

First Posted
November 5, 2015
Last Updated
September 5, 2018
Sponsor
Sun Yat-sen University
Collaborators
Beijing Tongren Hospital, Wenzhou Medical University, The Second Affiliated Hospital of Harbin Medical University, Huazhong University of Science and Technology, The Third Hospital of HanDan, Third Affiliated Hospital of Third Military Medical University, Central South University, He University, Hebei Provincial Eye Hospital
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1. Study Identification

Unique Protocol Identification Number
NCT02613013
Brief Title
Laser Peripheral Iridotomy Plus Laser Peripheral Iridoplasty for Primary Angle Closure
Official Title
Laser Peripheral Iridotomy Plus Laser Peripheral Iridoplasty for Primary Angle Closure With Multi-mechanism Based on UBM: A Randomized Controlled Trial
Study Type
Interventional

2. Study Status

Record Verification Date
September 2018
Overall Recruitment Status
Unknown status
Study Start Date
October 2015 (undefined)
Primary Completion Date
March 2020 (Anticipated)
Study Completion Date
April 2022 (Anticipated)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Sun Yat-sen University
Collaborators
Beijing Tongren Hospital, Wenzhou Medical University, The Second Affiliated Hospital of Harbin Medical University, Huazhong University of Science and Technology, The Third Hospital of HanDan, Third Affiliated Hospital of Third Military Medical University, Central South University, He University, Hebei Provincial Eye Hospital

4. Oversight

Data Monitoring Committee
Yes

5. Study Description

Brief Summary
This is a 10-centre randomized controlled clinical trial to explore whether laser peripheral iridoplasty (LPIP) plus laser peripheral iridotomy (LPI) is more effective than single LPI to control the progression of primary angle closure with multi-mechanism based on the UBM classification.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Glaucoma, Angle-Closure

7. Study Design

Primary Purpose
Treatment
Study Phase
Not Applicable
Interventional Study Model
Parallel Assignment
Masking
None (Open Label)
Allocation
Randomized
Enrollment
240 (Anticipated)

8. Arms, Groups, and Interventions

Arm Title
single LPI
Arm Type
Active Comparator
Arm Description
LPI was performed with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia will be administered. The treatment site was selected in the superior nasal iris or in a crypt, where present. Treatment was initiated with a pulse of 3-5mJ, the power was increased until patency was achieved, the opening of iris >0.1mm. and patency was determined by direct visualization of the posterior chamber.
Arm Title
LPIP plus LPI
Arm Type
Experimental
Arm Description
LPIP was applied with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia will be administered. Twenty to 30 spots of 250-300 mW power with 300-500 microns of size and duration of 400-500 ms were applied. Power was modified arbitrarily until an effective iris contraction was obtained. Effective iris contraction was considered as a concentric movement around the laser spot, with minimal iris pigmentation and immediate angle opening observed through the lens mirrors using a Goldmann lens. Power was lowered if there was any bursting sound perceived, pigment dispersion, air bubbles or considerable pain. LPI was performed after LPIP procedure
Intervention Type
Device
Intervention Name(s)
neodymium:yttrium-aluminum- garnet laser
Intervention Description
a neodymium:yttrium-aluminum- garnet laser was used to perform the LPI
Intervention Type
Device
Intervention Name(s)
frequency-doubled Q-switched neodymium:yttrium-aluminum-garnet 532-nm laser
Intervention Description
a frequency-doubled Q-switched neodymium:yttrium-aluminum-garnet 532-nm laser was used to perform the LPIP
Intervention Type
Drug
Intervention Name(s)
Pilocarpine
Intervention Description
30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia (Proparacaine) will be administered
Intervention Type
Procedure
Intervention Name(s)
LPIP plus LPI
Intervention Description
LPIP was applied with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia will be administered. Twenty to 30 spots of 250-300 mW power with 300-500 microns of size and duration of 400-500 ms were applied. Power was modified arbitrarily until an effective iris contraction was obtained. Effective iris contraction was considered as a concentric movement around the laser spot, with minimal iris pigmentation and immediate angle opening observed through the lens mirrors using a Goldmann lens. Power was lowered if there was any bursting sound perceived, pigment dispersion, air bubbles or considerable pain. LPI was performed after LPIP procedure.
Intervention Type
Drug
Intervention Name(s)
Proparacaine
Intervention Description
30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia (Proparacaine) will be administered
Intervention Type
Procedure
Intervention Name(s)
LPI
Intervention Description
LPI was performed with a VISULAS diode laser of 532 nm (Carl Zeiss Meditec, Dublin, CA). 30 minutes prior to the procedure, a drop of 2% pilocarpine will be instilled into the eye every 15 minutes, Topical anaesthesia (Proparacaine) will be administered. The treatment site was selected in the superior nasal iris or in a crypt, where present. Treatment was initiated with a pulse of 3-5mJ, the power was increased until patency was achieved, the opening of iris >0.1mm. and patency was determined by direct visualization of the posterior chamber.
Primary Outcome Measure Information:
Title
Progression rate determined by number of patients who progress after laser treatment for each group.
Description
PAC progression defined as presence of any of the following: Acute angle closure crisis Intraocular (IOP) was 8mmHg higher than initiation 1 month after the laser procedure IOP was ≥22mmHg when measured three times of continuous 1 month after the lase procedure The progression of peripheral anterior synechiae ≥ 1 clock hour within 3 years after the laser procedure as measured by gonioscopic examination. glaucomatous neuropathy within 3 years after the laser procedure
Time Frame
3 years
Secondary Outcome Measure Information:
Title
Additional medication or surgery required questionnaire
Description
the medication required to control the IOP the additional surgery required to control the progression of the PAC
Time Frame
3 years
Title
The change of the best corrected visual acuity after the laser procedure
Time Frame
3 years
Title
The number of the cornea endothelial cells
Time Frame
3 years
Title
The change in angle width and configuration as measured by ultrasound biomicroscopy (UBM)
Time Frame
3 years

10. Eligibility

Sex
All
Minimum Age & Unit of Time
40 Years
Maximum Age & Unit of Time
75 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Clinical diagnosis of primary angle closure (PAC), with IOP≤30mmHg and PAS≤270°. PAC with multi-mechanism based on UBM examination (multi-mechanism is defined as primary angle closure is caused by pupil block plus at least one kind of non-pupil block factors like (relative anterior position and thick of the ciliary body, the big volume of the iris, the anterior location of the iris insertion into the ciliary body)or any two or more kinds of combination. Visual acuity≥ 20/40 Age between 40-75 years old Chinese people If both eyes of a patient are eligible for the study, the e eye had worse visual acuity will be selected. Only one eye per patient is eligible for the study. Drug washout: Eligible patients who are already on anti-glaucoma medications are required to have drug washout before being randomized. Various medications have different washout periods: Prostaglandin analogues 4 weeks, Beta blockers 3 weeks, Adrenergic agonist 2 weeks, Cholinergic agonist 5 days, Carbonic Anhydrase Inhibitors 5 days. Patients whose IOP>30 mm Hg during this washout period will be stopped from further washout and be withdrawn from the study. Exclusion Criteria: Unwilling or unable to give consent, unwilling to accept randomization, or unable to return for scheduled protocol visits. Angle closure due to secondary causes (subluxed lens, neovascular, uveitic, traumatic, post-operative) Previous incisional intraocular surgery or ocular laser in study eye (LPI or LPIP, cyclodestructive procedure, cataract surgery) Primary angle closure with glaucomatous neuropathy. Have cataract in the studying eye and anticipated to have cataract surgery in the coming 3 years; the existing cataract affect visual field examination and fundus examination; the visual acuity <20/40 due to the existing cataract. Who are using IOP lowing drugs and do not have drug washout Need for glaucoma surgery combined with other ocular procedures (i.e. cataract surgery, penetrating keratoplasty, or retinal surgery) or anticipated need for urgent additional ocular surgery Coexisting other ocular diseases (i.e. cornea abnormal or cornea infection, Iridocorneal endothelial syndrome or anterior segment dysgenesis, nanophthalmos, high myopia (>6.0D), Chronic or recurrent uveitis, ocular cancer, trauma, central retinal vein occlusion, central retinal artery occlusion, retinal detachment) cornea endothelium counting <1000/mm2 need local or systemic steroid long-term use Unwilling to discontinue contact lens use after surgery Who are taking parting in other drug clinical trials Pregnant or nursing women Severe systemic disease (i.e. diabetes mellitus, hypertension, the end stage of cardiac disease, nephropathy disease, respiratory disease and cancer. Allergic to pilocarpine or alcaine Contraindication to ocular laser diseases.
Central Contact Person:
First Name & Middle Initial & Last Name or Official Title & Degree
xiulan zhang, MD,PhD
Email
zhangxl2@mail.sysu.edu.cn
Facility Information:
Facility Name
Zhongshan Ophthalmic Center
City
Guangzhou
State/Province
Guangdong
ZIP/Postal Code
510060
Country
China
Individual Site Status
Recruiting
Facility Contact:
First Name & Middle Initial & Last Name & Degree
Xiulan Zhang, MD,PhD
Email
zhangxl2@mail.sysu.edu.cn
First Name & Middle Initial & Last Name & Degree
Xiulan Zhang, MD,PhD

12. IPD Sharing Statement

Citations:
PubMed Identifier
28302178
Citation
Chen S, Lv J, Fan S, Zhang H, Xie L, Xu L, Jiang B, Yuan H, Liang Y, Li S, Chen P, Zhang X, Wang N; Multi-mechanism Angle Closure Study (MACs) group. Laser peripheral iridotomy versus laser peripheral iridotomy plus laser peripheral iridoplasty in the treatment of multi-mechanism angle closure: study protocol for a randomized controlled trial. Trials. 2017 Mar 17;18(1):130. doi: 10.1186/s13063-017-1860-4.
Results Reference
derived

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Laser Peripheral Iridotomy Plus Laser Peripheral Iridoplasty for Primary Angle Closure

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