Laser Treatment for Glaucoma Prevention in Corneal Disease

Overseen By Soumaya Bouhout, MD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Centre hospitalier de l'Université de Montréal (CHUM)

Disqualifiers: Age, Other glaucoma study, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 3

20 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores a laser treatment to help prevent glaucoma, a condition that can damage the eye's optic nerve and lead to vision loss, in individuals requiring a special corneal implant called the Boston keratoprosthesis (KPro). Researchers are testing two types of laser treatments, including G-Probe transscleral cyclophotocoagulation, to lower eye pressure before KPro surgery, aiming to prevent glaucoma from worsening. The trial seeks participants scheduled for a Boston KPro who haven't had recent glaucoma surgery.

As an unphased trial, this study offers a unique opportunity to contribute to groundbreaking research that could improve future treatment options for glaucoma patients.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What prior data suggests that this laser treatment is safe for glaucoma prevention in corneal disease?

Research shows that both G-Probe and Micropulse laser treatments are generally safe for lowering eye pressure in people with glaucoma. Studies have found that the G-Probe method can quickly and effectively reduce eye pressure, making it a good option for difficult cases of glaucoma.

Micropulse laser treatment is also effective and safe for many patients, helping to lower eye pressure, which is crucial for managing glaucoma. Long-term studies, including those lasting up to five years, have demonstrated that this treatment remains effective without major side effects.

Overall, both treatments are considered safe options for managing high eye pressure, which is key to preventing vision loss from glaucoma. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about the use of laser treatments like G-Probe and MicroPulse for preventing glaucoma in patients with corneal disease because they offer a proactive approach. Unlike traditional glaucoma treatments that often focus on managing symptoms after they appear, these laser methods aim to prevent the condition from developing in the first place. The G-Probe uses a diode laser to deliver energy directly to the eye's ciliary body, potentially reducing fluid production and intraocular pressure. Meanwhile, the MicroPulse system uses micropulse waves, which might offer more precise control over the treatment and minimize damage to surrounding tissues. This proactive and potentially gentler approach is what makes these treatments stand out.

What evidence suggests that this trial's laser treatments could be effective for preventing glaucoma in corneal disease?

Research has shown that transscleral cyclophotocoagulation (TS-CPC) effectively lowers eye pressure in people with glaucoma. In this trial, participants will receive either the G-Probe method or the micropulse method in separate treatment arms. The G-Probe method offers a non-invasive way to reduce eye pressure, making it suitable for those unable to undergo traditional surgery. The micropulse method also effectively lowers eye pressure and may reduce the need for pressure-lowering eye drops over time. Both methods are safe and can help manage glaucoma in patients with complex eye conditions. These findings suggest that using TS-CPC before corneal procedures could prevent glaucoma in at-risk patients. ^{5 6 7 8 9}

Who Is on the Research Team?

Marie-Claude Robert, MD, MSc

Principal Investigator

Ophthalmology Department, Centre Hospitalier de l'Université de Montreal

Are You a Good Fit for This Trial?

This trial is for adults who need a Boston keratoprosthesis (KPro) to replace their cornea and can follow the study's procedures. It excludes those under 18 or over 80, with severe ocular surface disease, terminal glaucoma, intra-ocular tumors, recent glaucoma surgery, or certain other conditions.

Inclusion Criteria

Able to give an informed consent

Candidate for the Boston keratoprosthesis type I

I am 18 years old or older.

Exclusion Criteria

I have ocular albinism.

I have a tumor inside my eye.

Participating in another interventional glaucoma study

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Prophylactic Treatment

Participants receive prophylactic transscleral cyclophotocoagulation treatment 4-8 weeks before Boston keratoprosthesis surgery

4-8 weeks

1 visit (in-person)

Post-Treatment Follow-up

Participants are examined by a glaucoma specialist 1 week following the laser treatment

1 week

1 visit (in-person)

Postoperative Follow-up

Participants are monitored for safety and effectiveness after Boston keratoprosthesis surgery

5 years

Day-1, weeks 1 and 2, months 1 and 3, then every 4-6 months

What Are the Treatments Tested in This Trial?

Interventions

• G-Probe transscleral cyclphophotocoagulation
• Transscleral cyclphophotocoagulation using the Micropulse system

Trial Overview The study tests if using transscleral cyclophotocoagulation (TS-CPC) before KPro surgery helps control eye pressure and prevent glaucoma. Participants are randomly assigned to receive either G-Probe TS-CPC or Micropulse TS-CPC from a specialist.

How Is the Trial Designed?

Group I: MicroPulse Treatment Experimental Treatment 1 Intervention

Prophylactic transscleral cyclophotocoagulation treatment, delivered by micropulse waves will be given 4-8 weeks before the Boston keratoprosthesis surgery.

Group II: G-Probe Treatment Experimental Treatment 1 Intervention

Prophylactic transscleral cyclophotocoagulation treatment, delivered with a diode laser using the G-Probe device, will be given 4-8 weeks before the Boston keratoprosthesis surgery.

Group III: Historical Cohort Active Control 1 Intervention

An historical cohort composed of patients who received a Boston keratoprosthesis between january 2017 and january 2019 will be included. Only patients who did not receive any glaucoma treatment 3 months before their surgery will be included. A total of 10 patients will be selected with the goal of matching the preoperative characteristics of the interventional patients. This group will serve as the control group in our study. Retrospective chart review will be performed for this branch.

Who Is Running the Clinical Trial?

Centre hospitalier de l'Université de Montréal (CHUM)

Lead Sponsor

Trials

389

Recruited

143,000+

Fonds de recherche en ophtalmologie de l'Université de Montréal

Collaborator

Trials

6

Recruited

160+

Published Research Related to This Trial

Micropulse Transscleral Cyclophotocoagulation (MP-TSCPC) effectively reduced intraocular pressure (IOP) in patients with advanced and refractory glaucoma, showing significant reductions at 1, 3, and 6 months post-treatment for both primary and additional therapy groups.

The success rates for controlling IOP were high for both groups, with 87% for primary therapy and 91% for additional therapy at 1 month, indicating that MP-TSCPC is a viable option for patients at high risk for invasive surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short-term outcomes of micropulse transscleral cyclophotocoagulation as a primary versus additional therapy in eyes with uncontrolled glaucoma. Rajendrababu, S., Senthilkumar, VA., Tara, TD., et al.[2023]

MicroPulse® transscleral cyclophotocoagulation (µP-TSCPC) was found to be effective in reducing intraocular pressure (IOP) by an average of 52% after 12 months in 71 eyes of patients with various types of glaucoma, with no significant change in visual acuity.

The procedure demonstrated a high surgical success rate of 90% to 95.7% within the first six months, and importantly, no significant adverse events or complications were reported, indicating a strong safety profile.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Outcome Of MicroPulse® Transscleral Photocoagulation In Different Types Of Glaucoma. Al Habash, A., AlAhmadi, AS.[2022]

Micropulse cyclophotocoagulation (MP CPC) demonstrated a 30% or greater reduction in intraocular pressure (IOP) in 53.4% of treated eyes among a cohort of 47 patients with various types of glaucoma, indicating its efficacy as a treatment option.

The procedure is non-incisional with a high safety profile and minimal complications, making it suitable for patients with different stages and types of glaucoma, and it can be repeated if necessary.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Our experience with micropulse cyclophotocoagulation in the therapy of glaucoma. Nutterová, E., Pitrová, Š., Lešták, J.[2020]

Micropulse transscleral cyclophotocoagulation (MP-CPC) effectively reduced intraocular pressure (IOP) by an average of 51% in patients with refractory glaucoma, with treatment success rates of 75% at 3 months and 67% at the last follow-up (mean follow-up of 7.8 months).

While MP-CPC showed promising efficacy, it was associated with complications in some patients, including hypotony (8.8%), prolonged inflammation (26%), and vision loss (17%), suggesting careful monitoring and consideration of treatment frequency is necessary.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Clinical Efficacy and Safety Profile of Micropulse Transscleral Cyclophotocoagulation in Refractory Glaucoma. Williams, AL., Moster, MR., Rahmatnejad, K., et al.[2022]

In a study of 37 patients who underwent micropulse transscleral cyclophotocoagulation (MP-CPC) for glaucoma, a significant correlation was found between reduced intraocular pressure (IOP) and increased anterior chamber flare at 1 and 4 weeks post-surgery.

The results suggest that while MP-CPC effectively lowers IOP, it also causes anterior chamber inflammation, indicating a complex relationship that may need further investigation to understand the implications for patient safety and treatment outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Correlation between intraocular pressure reduction and anterior chamber aqueous flare after micropulse transscleral cyclophotocoagulation. Kimura, A., Nakashima, KI., Inoue, T.[2021]

MicroPulse transscleral laser therapy (MP-TLT) is as effective as continuous-wave transscleral cyclophotocoagulation (CW-TSCPC) in lowering intraocular pressure (IOP) in glaucoma patients, with success rates of 87.5% for MP-TLT and 88.6% for CW-TSCPC after 12 months.

MP-TLT has a better safety profile, allowing it to be used in earlier stages of glaucoma and in patients with good central vision, making it a promising option for broader treatment applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MicroPulse Transscleral Laser Therapy Demonstrates Similar Efficacy with a Superior and More Favorable Safety Profile Compared to Continuous-Wave Transscleral Cyclophotocoagulation. Bernardi, E., Töteberg-Harms, M.[2022]

Micropulse transscleral cyclophotocoagulation (MP-TSCPC) effectively reduced intraocular pressure (IOP) in patients with uncontrolled glaucoma, achieving a mean reduction of 41.2% at one month and continuing to lower IOP over a 12-month follow-up period.

While MP-TSCPC decreased the need for ocular antihypertensive medications, it was associated with complications such as inflammation and vision loss in some patients, indicating the need for careful patient selection and monitoring.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Micropulse Cyclophotocoagulation: Initial Results in Refractory Glaucoma. Emanuel, ME., Grover, DS., Fellman, RL., et al.[2022]

Micropulse transscleral diode laser cyclophotocoagulation (TSCPC) effectively reduced intraocular pressure (IOP) in patients with refractory glaucoma, with significant decreases observed at multiple follow-up points over 18 months.

The procedure demonstrated a high success rate of 72.7% without any cases of hypotony or loss of best-corrected visual acuity, indicating it is a safe alternative to conventional TSCPC.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Micropulse transscleral diode laser cyclophotocoagulation in the treatment of refractory glaucoma. Tan, AM., Chockalingam, M., Aquino, MC., et al.[2022]

Micropulse transscleral cyclophotocoagulation is a new technique that uses repetitive micropulses of laser energy to treat glaucoma, showing promise in managing intraocular pressure.

Current research highlights gaps in understanding the exact mechanism of action and optimal laser settings, indicating that further studies are needed to refine this treatment approach.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Update on Micropulse Transscleral Cyclophotocoagulation. Sanchez, FG., Peirano-Bonomi, JC., Brossard Barbosa, N., et al.[2021]

Micropulse trans-scleral cyclophotocoagulation (TSCPC) effectively lowers intraocular pressure (IOP) in glaucoma patients, with mean IOP decreasing from 23.5 mm Hg preoperatively to around 16.8 mm Hg at 24 months post-treatment, based on a study of 141 eyes over two years.

The treatment is also associated with a reduction in the number of IOP-lowering medications needed, from an average of 3.3 preoperatively to 2.2 at 24 months, and has a favorable safety profile with mostly reversible complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Micropulse Trans-scleral Cyclophotocoagulation in Patients With Glaucoma: 1- and 2-Year Treatment Outcomes. de Crom, RMPC., Slangen, CGMM., Kujovic-Aleksov, S., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC11152606/

Outcomes of slow coagulation transscleral ... SC-TSCPC is an effective, non-incisional IOP-lowering procedure in phakic and pseudophakic eyes that may not otherwise be ideal candidates for incisional ...

2. nature.com nature.com/articles/s41598-024-75246-y

Comparison of treatment outcomes between slow ... This study compared treatment outcomes of slow coagulation transscleral cyclophotocoagulation (SC-CPC, 65 eyes) and micropulse transscleral laser treatment ( ...

3. clinicaltrials.gov clinicaltrials.gov/study/NCT04232982

Study Details | NCT04232982 | The Role of Transscleral ... HYPOTHESIS Our hypothesis is that prophylactic transscleral cyclophotocoagulation will decrease glaucoma progression as well as the risks of developing glaucoma ...

4. iridex.com iridex.com/portals/0/instrumentation/TSCPC%202012.pdf

Reconsidering Transscleral Cyclophotocoagulation A viable option for many types of glaucoma. ▻ Safety Profile of TSCPC. ▻ Benefits of Noninvasive Glaucoma Surgery. ▻ Benefits of the G-Probe in Practice.

5. onlinelibrary.wiley.com onlinelibrary.wiley.com/doi/10.1111/aos.15754

Efficacy and safety of transscleral cyclophotocoagulation ... Diode laser TSCPC and CCT had nearly equivalent clinical efficacy in treating intractable glaucoma, while CCT demonstrated a better IOP-lowering effect in non- ...

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8846995/

MicroPulse Transscleral Laser Therapy Demonstrates Similar ... The aim of this study was to compare effectiveness and safety of MicroPulse transscleral laser therapy (MP-TLT) using the original MicroPulse P3 ...

7. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC8852201/

Outcomes of initial and repeat micro-pulse transscleral ... MP-TSCPC is a safe and effective non-invasive means to lower IOP in a variety of glaucoma patients. While over 50% (34/67) of eyes required ...

8. iridex.com iridex.com/PhysicianEducation/Glaucoma/TSCPCG-Probe.aspx

Transscleral cyclophotocoagulation (TSCPC) High ... Enjoy long-lasting IOP lowering effects for cases with Refractory Glaucoma. G-Probe™ Glaucoma Device provides repeatable and quick procedure.

9. sciencedirect.com sciencedirect.com/science/article/pii/S2451993624000823

Outcomes of slow coagulation transscleral ... To evaluate outcomes of slow coagulation transscleral cyclophotocoagulation (SC-TSCPC) in a primarily African American patient population with glaucoma.