Refractory GlaucomaNCT05230355
Comparison Between Two Techniques of Subthreshold Diode Laser Cyclophotocoagulation in Refractory Glaucoma
A study testing standard technique and modified pattern in people with Refractory Glaucoma, run by Assiut University at 1 site in Egypt.
Trial summary
The aim of this study is to assess the results of subliminal subthreshold transscleral diode cyclophotocoagulation in refractory glaucoma using the standard technique of 360 degree application and to compare the outcome with a modified technique both in terms of efficacy and safety. Read more about this study
- Who is it for?
- Any ageHealthy volunteers can take part
- Conditions the study is for
- Refractory Glaucoma
- What is being tested?
- standard technique and modified pattern
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 32 participants
- Where
- 1 siteEgypt
- Study dates
- 1 Feb 2022to 1 Feb 2025
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Who may be able to join
- patients with refractory glaucoma (IOP > 21 mmHg unresponsive to maximally tolerated antiglaucoma medications, previously failed surgical treatment, or both)
Who cannot join
- Ocular inflammation.
- Ocular infection.
- Recent ocular surgery in the study eye in the 2 months prior to enrolment.
Trial locations and contacts
1 site in 1 country.
About this study
The aim of this study is to assess the results of subliminal subthreshold transscleral diode cyclophotocoagulation in refractory glaucoma using the standard technique of 360 degree application and to compare the outcome with a modified technique both in terms of efficacy and safety.
Read the detailed description
Refractory glaucoma is glaucoma that doesn't respond favorably to surgical and/or medical treatment to lower intraocular pressure. It can include primary open angle glaucoma, primary angle closure glaucoma, neovascular glaucoma or silicone oil-induced glaucoma. Cyclophotocoagulation (CPC) is a form of cycloablation using laser to treat glaucoma. It involves ciliary body destruction by targeting the ciliary epithelium and stroma, resulting in a reduction in aqueous secretion and hence intraocular pressure. Transscleral cyclophotocoagulation using a continuous diode laser has been a treatment option in advanced glaucoma cases with s¬¬uboptimal IOP control, for a long time. High treatment energy used by diode laser cyclophotocoagulation was argued to be associated with increased frequency of serious complications such as vision loss, hypotony, and phthisis. These concerns necessitate modulation of the parameters of laser treatment used.
Micropulse transscleral cyclophotocoagulation (MP-TSCPC), which is a variation of conventional continuous-wave CPC, has emerged as an attractive alternative for the treatment of many types of glaucoma. It breaks the continuous wave laser into multiple short and repetitive pulses that allow the tissue to cool down between applications, thus reducing thermal damage. This strategy delivers very short energy pulses followed by rest periods, which is known as "duty cycle" and is defined as the ratio of time that a laser is delivering energy vs resting (ON/OFF). For this procedure, an infrared diode laser is used to stimulate the ciliary body structures and the uveoscleral pathway. This way it reduces the production of the aqueous humour and facilitates the uveoscleral outflow, with IOP reduction as a final effect.
Despite promising results, only few clinical studies are published on MP-TSCPC and most of them are retrospective studies refer to patients having previous continuous wave transscleral cyclophotocoagulation. Moreover, Several parameters and protocols have been studied in other reports in an attempt to refine the standard technique aiming to improve the outcomes without increasing the adverse effects.
- Conditions
- Refractory Glaucoma
- Being tested
- standard technique, modified pattern
- Medical subject headings
- Glaucoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
standard techniqueDevice
The probe was moved over each hemisphere for 120 seconds (a total of 240 seconds). Total energy = 2.5 x 0.313 x 240 = 187.8 J
modified patternDevice
The probe was moved over 3 quadrants for 80 seconds for each quadrant (a total of 240 seconds). Total energy = 2.5 x 0.313 x 240 = 187.8 J
| Study group | Role | What they receive |
|---|---|---|
| group A the standard technique | Active comparator | The tip of the probe was moved in a "painting" motion along the upper and lower hemispheres over pars plana, 3 mm behind the limbus, avoiding the 3 and 9 o'clock positions. Receives: Device: standard technique |
| Group B a modified technique | Active comparator | The probe tip was moved for 2 mm perpendicular to a line 3 mm parallel to the cornea, aiming to cover the largest circumference of the ciliary body area. Receives: Device: modified pattern |
What is being measured
The primary outcome is the main question the study is designed to answer.
IOP reduction success rate
Success rate is defined as achieving an IOP between 5 and 21 mmHg or at least a 20% reduction in IOP at the final follow up with or without IOP lowering medications
Measured: 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Feb 2022
- Study start1 Feb 2022
- Primary completion1 Aug 2024
- Study completion1 Feb 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Refractory GlaucomaStudies of the same condition, open and under way.
- More trials run by Assiut UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Assiut University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Mohamed Omar, Assiut University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05230355
- Sponsor's protocol ID
- CTTSDLCRG
- Status last verified
- Jan 2022
- First submitted
- 20 Jan 2022
- Last updated
- 10 Jul 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 10 Jul 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison Between Two Techniques of Subthreshold Diode Laser Cyclophotocoagulation in Refractory Glaucoma
- ClinicalTrials.gov ID
- NCT05230355
- Acronym / sponsor ID
- CTTSDLCRG
- Conditions
- Refractory Glaucoma
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Assiut UniversityUniversity, hospital or other
- Study start
- 1 Feb 2022 (actual)
- Primary completion
- 1 Aug 2024 (actual)
- Study completion
- 1 Feb 2025 (actual)
- First posted
- 8 Feb 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The aim of this study is to assess the results of subliminal subthreshold transscleral diode cyclophotocoagulation in refractory glaucoma using the standard technique of 360 degree application and to compare the outcome with a modified technique both in terms of efficacy and safety.
Detailed description
Refractory glaucoma is glaucoma that doesn't respond favorably to surgical and/or medical treatment to lower intraocular pressure. It can include primary open angle glaucoma, primary angle closure glaucoma, neovascular glaucoma or silicone oil-induced glaucoma. Cyclophotocoagulation (CPC) is a form of cycloablation using laser to treat glaucoma. It involves ciliary body destruction by targeting the ciliary epithelium and stroma, resulting in a reduction in aqueous secretion and hence intraocular pressure. Transscleral cyclophotocoagulation using a continuous diode laser has been a treatment option in advanced glaucoma cases with s¬¬uboptimal IOP control, for a long time. High treatment energy used by diode laser cyclophotocoagulation was argued to be associated with increased frequency of serious complications such as vision loss, hypotony, and phthisis. These concerns necessitate modulation of the parameters of laser treatment used.
Micropulse transscleral cyclophotocoagulation (MP-TSCPC), which is a variation of conventional continuous-wave CPC, has emerged as an attractive alternative for the treatment of many types of glaucoma. It breaks the continuous wave laser into multiple short and repetitive pulses that allow the tissue to cool down between applications, thus reducing thermal damage. This strategy delivers very short energy pulses followed by rest periods, which is known as "duty cycle" and is defined as the ratio of time that a laser is delivering energy vs resting (ON/OFF). For this procedure, an infrared diode laser is used to stimulate the ciliary body structures and the uveoscleral pathway. This way it reduces the production of the aqueous humour and facilitates the uveoscleral outflow, with IOP reduction as a final effect.
Despite promising results, only few clinical studies are published on MP-TSCPC and most of them are retrospective studies refer to patients having previous continuous wave transscleral cyclophotocoagulation. Moreover, Several parameters and protocols have been studied in other reports in an attempt to refine the standard technique aiming to improve the outcomes without increasing the adverse effects.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Single blind (participant)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| group A the standard technique | Active comparator | Device: standard techniqueThe tip of the probe was moved in a "painting" motion along the upper and lower hemispheres over pars plana, 3 mm behind the limbus, avoiding the 3 and 9 o'clock positions. |
| Group B a modified technique | Active comparator | Device: modified patternThe probe tip was moved for 2 mm perpendicular to a line 3 mm parallel to the cornea, aiming to cover the largest circumference of the ciliary body area. |
Who may qualify
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult, Older adult
Key inclusion criteria (1 listed)
- patients with refractory glaucoma (IOP > 21 mmHg unresponsive to maximally tolerated antiglaucoma medications, previously failed surgical treatment, or both)
Key exclusion criteria (3 listed)
- Ocular inflammation.
- Ocular infection.
- Recent ocular surgery in the study eye in the 2 months prior to enrolment.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| standard techniqueThe probe was moved over each hemisphere for 120 seconds (a total of 240 seconds). Total energy = 2.5 x 0.313 x 240 = 187.8 J | Device | group A the standard technique |
| modified patternThe probe was moved over 3 quadrants for 80 seconds for each quadrant (a total of 240 seconds). Total energy = 2.5 x 0.313 x 240 = 187.8 J | Device | Group B a modified technique |
Primary outcome
IOP reduction success rate
Time frame: 6 months
Success rate is defined as achieving an IOP between 5 and 21 mmHg or at least a 20% reduction in IOP at the final follow up with or without IOP lowering medications
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 10 Jul 2025.
- Individual participant dataSharing planned: No
Related trials for Refractory Glaucoma
Recruiting
Safety and Effectiveness of the VisiPlate Aqueous Shunt in Patients With Refractory Open-Angle Glaucoma
Open Angle Glaucoma (OAG)
Recruiting
Innovative Tube Trabeculectomy for Advanced and Refractory Glaucoma: A Randomized Controlled Trial
Glaucoma, Trabeculectomy
Recruiting
The Vizio Clinical Study
Refractory Glaucoma
Enrolling by invitation
Efficacy and Safety of Posterior Chamber Glaucoma Drainage Device
Refractory Glaucoma
Not yet recruitingPhase 3
Effect of Mitomycin-C on the Outcomes of Patients Receiving Ahmed Glaucoma Valve Implantation Surgery
Glaucoma
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing standard technique and modified pattern in people with Refractory Glaucoma, run by Assiut University at 1 site in Egypt.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 10 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Egypt. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
IOP reduction success rate (time frame: 6 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 10 Jul 2025.