Primary Angle-Closure GlaucomaNCT03647033
Phacoemulsification Versus Phacoemulsification With Micro-bypass Stent
A study testing iStent implantation in people with Primary Angle-Closure Glaucoma and Primary Angle Closure Without Glaucoma Damage, run by Khoo Teck Puat Hospital at 1 site in Singapore.
Trial summary
Assessing the safety and efficacy of a micro-bypass stent in combination with cataract surgery in subjects with primary angle closure. Subjects are randomized into two arms: phacoemulsification cataract surgery alone versus phacoemulsification cataract surgery combined with the micro-bypass stent implantation. Read more about this study
- Who is it for?
- Ages 21 to 80 years
- Conditions the study is for
- Primary Angle-Closure Glaucoma, Primary Angle Closure Without Glaucoma Damage
- What is being tested?
- iStent implantation
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 32 participants
- Where
- 1 siteSingapore
- Study dates
- 14 Oct 2015to 12 Aug 2017
- Phase
- Interventional
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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 21 to 80 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- able to provide informed consent
- Previous diagnosis of Primary Angle Closure or Primary Angle Closure Glaucoma
- Intraocular Pressure above 21mmHg at 3 separate visits
- On 1 or more hypotensive medications
- Pre-operative visual acuity of no better than 6/12
Who cannot join
- Other glaucoma diagnosis: Primary Open Angle Glaucoma, secondary glaucoma
- Peripheral Anterior Synechiae in the nasal and inferior quadrant
- Cloudy cornea affecting view for iStent implantation
- Previous glaucoma surgery
- History of Ocular trauma
- Ocular surface disease
- Pre-proliferative or proliferative diabetic retinopathy
- Age related macular degeneration with macular scar or macular atrophy
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Phacoemulsification Versus Phacoemulsification With Micro-bypass Stent Implantation in Primary Angle Closure and Primary Angle Closure Glaucoma: Randomized Double-masked Clinical Trial
Assessing the safety and efficacy of a micro-bypass stent in combination with cataract surgery in subjects with primary angle closure. Subjects are randomized into two arms: phacoemulsification cataract surgery alone versus phacoemulsification cataract surgery combined with the micro-bypass stent implantation. Post surgery intraocular eye pressure will be recorded to assess the efficacy of both arms.
Read the detailed description
Aim: To assess the safety and efficacy of the iStent trabecular micro-bypass stent (Glaukos Corporation, Laguna Hills, CA) in combination with cataract surgery in subjects with primary angle closure and mild to moderate primary angle closure glaucoma
Method: Prospective, randomised controlled trial, blinded to patient and intra-ocular pressure measuring staff. 32 patients, 1:1 ratio, in 2 arms of phacoemulsification alone compared to phacoemulsification with iStent.
Hypothesis: Phacoemulsification with micro-bypass stent has a better intraocular pressure (IOP) lowering effect compared to phacoemulsification alone in primary angle closure and primary angle closure glaucoma at 1 year after surgery.
Importance: Primary angle closure and primary angle closure glaucoma are conventionally treated with eye drops that lower the intraocular pressure (IOP). Phacoemulsification/lens extraction can often help lower the eye pressure by widening the drainage angle and via ultrasound mechanisms, however, in some cases the IOP is not lowered, or even can cause the IOP to be higher. The iStent implant can be used together with phacoemulsification to lower the IOP and in Primary open angle glaucoma, it gives an additional 20% IOP reduction. It is unclear what effect the iStent has in primary angle closure or primary angle closure glaucoma as it has never been studied. It is important because primary angle closure glaucoma is much more common in the Singaporean Chinese population and the iStent can potentially be used to control the IOP instead of conventional eye drops and glaucoma surgery which have their own potential adverse effects.
Potential Benefits: iStent with phacoemulsification may control the IOP better than phacoemulsification alone, reduce the need for IOP lowering medication after surgery, and prevent the need for glaucoma surgery in the future.
Potential Risks: The iStent has risks of IOP spikes, bleeding in the anterior chamber and iStent dislocation.Phacoemulsification has the risks of: infection, bleeding, reduced vision, inflammation, posterior capsular rupture, vitreous loss, retinal detachment, endophthalmitis, suprachoroidal haemorrhage and Intraocular Lens dislocation.
- Being tested
- iStent implantation
- Keywords
- istent, primary angle closure
- Medical subject headings
- Glaucoma, Angle-Closure
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
iStent implantationDevice
The iStent is a FDA and Health Sciences Authority (HSA) approved micro-bypass stent device that bypasses the trabecular meshwork (filtration membrane of the aqueous fluid exit pathway) and reroutes aqueous from the anterior chamber directly into canal of Schlemm and out of the eye. It lowers the intraocular pressure (IOP) by increasing the outflow of fluid from the eye from the micro-bypass. In angle closure, the lens has to be removed to create enough space for the iStent to be inserted.
| Study group | Role | What they receive |
|---|---|---|
| phacoemulsification alone | No intervention | routine phacoemulsification cataract surgery with intraocular lens implantation |
| phacoemulsification and iStent | Experimental | phacoemulsification cataract surgery with intraocular lens implantation combined with iStent implantation Receives: Device: iStent implantation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Intraocular Pressure Between Baseline and 1 Year
change in mean unmedicated intraocular pressure between baseline and 1 year
Measured: 1 year
Secondary outcomes (1)
Change in Glaucoma Medications
change in number of topical glaucoma medications at 1 year post operation
Measured: 1 year
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Aug 2018
- Study start14 Oct 2015
- Primary completion12 Aug 2016
- Study completion12 Aug 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Primary Angle-Closure GlaucomaStudies of the same condition, open and under way.
- 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
- Model description
- Single centre, randomised prospective trial, the patient and the intraocular pressure (IOP)checking staff will be blinded. Randomised by random envelope shuffle technique. 1:1 ratio allocation 2 arms: phacoemulsification alone and phacoemulsification and iStent. 16 patients in each arm, 32 patients in total. The post-operative management is the same for both arms After operation the patient will be followed up at day 1, week 1, week 2, months 1, 3, 6 and 12. At each visit the patient will have the following tests: Tonometry (IOP check) - Not to be taken by the operating surgeon, to be taken by 2 people, one IOP checker and one reader.
- Masking
- Double blind
- Who is masked
- Participant, Outcomes assessor
- Enrolment
- 32 participants (actual)
Sponsor and investigators
- Lead sponsor
- Khoo Teck Puat Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Philemon Huang, MMed, FAMS, Principal investigator, National Healthcare Group, Singapore
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03647033
- Sponsor's protocol ID
- 2015/00644
- Other IDs
- 2015
- Status last verified
- Sep 2018
- First submitted
- 23 Aug 2018
- Last updated
- 31 Oct 2018
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- Undecided
Publications
Craven ER, Katz LJ, Wells JM, Giamporcaro JE; iStent Study Group. Cataract surgery with trabecular micro-bypass stent implantation in patients with mild-to-moderate open-angle glaucoma and cataract: two-year follow-up. J Cataract Refract Surg. 2012 Aug;38(8):1339-45. doi: 10.1016/j.jcrs.2012.03.025.
PubMed 22814041Fea AM. Phacoemulsification versus phacoemulsification with micro-bypass stent implantation in primary open-angle glaucoma: randomized double-masked clinical trial. J Cataract Refract Surg. 2010 Mar;36(3):407-12. doi: 10.1016/j.jcrs.2009.10.031.
PubMed 20202537Malvankar-Mehta MS, Iordanous Y, Chen YN, Wang WW, Patel SS, Costella J, Hutnik CM. iStent with Phacoemulsification versus Phacoemulsification Alone for Patients with Glaucoma and Cataract: A Meta-Analysis. PLoS One. 2015 Jul 6;10(7):e0131770. doi: 10.1371/journal.pone.0131770. eCollection 2015.
PubMed 26147908Samuelson TW, Katz LJ, Wells JM, Duh YJ, Giamporcaro JE; US iStent Study Group. Randomized evaluation of the trabecular micro-bypass stent with phacoemulsification in patients with glaucoma and cataract. Ophthalmology. 2011 Mar;118(3):459-67. doi: 10.1016/j.ophtha.2010.07.007. Epub 2010 Sep 15.
PubMed 20828829
Study at a glance
From the registry record, last updated by the sponsor on 31 Oct 2018. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phacoemulsification Versus Phacoemulsification With Micro-bypass Stent Implantation in Primary Angle Closure and Primary Angle Closure Glaucoma: Randomized Double-masked Clinical Trial
- ClinicalTrials.gov ID
- NCT03647033
- Acronym / sponsor ID
- 2015/00644
- Keywords
- istent, primary angle closure
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 32 participants (actual)
- Lead sponsor
- Khoo Teck Puat HospitalUniversity, hospital or other
- Study start
- 14 Oct 2015 (actual)
- Primary completion
- 12 Aug 2016 (actual)
- Study completion
- 12 Aug 2017 (actual)
- First posted
- 27 Aug 2018 (actual)
- Results
- Posted 2 Oct 2018
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Assessing the safety and efficacy of a micro-bypass stent in combination with cataract surgery in subjects with primary angle closure. Subjects are randomized into two arms: phacoemulsification cataract surgery alone versus phacoemulsification cataract surgery combined with the micro-bypass stent implantation. Post surgery intraocular eye pressure will be recorded to assess the efficacy of both arms.
Detailed description
Aim: To assess the safety and efficacy of the iStent trabecular micro-bypass stent (Glaukos Corporation, Laguna Hills, CA) in combination with cataract surgery in subjects with primary angle closure and mild to moderate primary angle closure glaucoma
Method: Prospective, randomised controlled trial, blinded to patient and intra-ocular pressure measuring staff. 32 patients, 1:1 ratio, in 2 arms of phacoemulsification alone compared to phacoemulsification with iStent.
Hypothesis: Phacoemulsification with micro-bypass stent has a better intraocular pressure (IOP) lowering effect compared to phacoemulsification alone in primary angle closure and primary angle closure glaucoma at 1 year after surgery.
Importance: Primary angle closure and primary angle closure glaucoma are conventionally treated with eye drops that lower the intraocular pressure (IOP). Phacoemulsification/lens extraction can often help lower the eye pressure by widening the drainage angle and via ultrasound mechanisms, however, in some cases the IOP is not lowered, or even can cause the IOP to be higher. The iStent implant can be used together with phacoemulsification to lower the IOP and in Primary open angle glaucoma, it gives an additional 20% IOP reduction. It is unclear what effect the iStent has in primary angle closure or primary angle closure glaucoma as it has never been studied. It is important because primary angle closure glaucoma is much more common in the Singaporean Chinese population and the iStent can potentially be used to control the IOP instead of conventional eye drops and glaucoma surgery which have their own potential adverse effects.
Potential Benefits: iStent with phacoemulsification may control the IOP better than phacoemulsification alone, reduce the need for IOP lowering medication after surgery, and prevent the need for glaucoma surgery in the future.
Potential Risks: The iStent has risks of IOP spikes, bleeding in the anterior chamber and iStent dislocation.Phacoemulsification has the risks of: infection, bleeding, reduced vision, inflammation, posterior capsular rupture, vitreous loss, retinal detachment, endophthalmitis, suprachoroidal haemorrhage and Intraocular Lens dislocation.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind (participant, outcomes assessor)
- Number of arms
- 2
- Model description
- Single centre, randomised prospective trial, the patient and the intraocular pressure (IOP)checking staff will be blinded. Randomised by random envelope shuffle technique. 1:1 ratio allocation 2 arms: phacoemulsification alone and phacoemulsification and iStent. 16 patients in each arm, 32 patients in total. The post-operative management is the same for both arms After operation the patient will be followed up at day 1, week 1, week 2, months 1, 3, 6 and 12. At each visit the patient will have the following tests: Tonometry (IOP check) - Not to be taken by the operating surgeon, to be taken by 2 people, one IOP checker and one reader.
| Arm | Type | Receives |
|---|---|---|
| phacoemulsification alone | No intervention | –routine phacoemulsification cataract surgery with intraocular lens implantation |
| phacoemulsification and iStent | Experimental | Device: iStent implantationphacoemulsification cataract surgery with intraocular lens implantation combined with iStent implantation |
Who may qualify
- Ages
- 21 to 80 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- able to provide informed consent
- Previous diagnosis of Primary Angle Closure or Primary Angle Closure Glaucoma
- Intraocular Pressure above 21mmHg at 3 separate visits
- On 1 or more hypotensive medications
- Pre-operative visual acuity of no better than 6/12
Key exclusion criteria (8 listed)
- Other glaucoma diagnosis: Primary Open Angle Glaucoma, secondary glaucoma
- Peripheral Anterior Synechiae in the nasal and inferior quadrant
- Cloudy cornea affecting view for iStent implantation
- Previous glaucoma surgery
- History of Ocular trauma
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 |
|---|---|---|
| iStent implantationThe iStent is a FDA and Health Sciences Authority (HSA) approved micro-bypass stent device that bypasses the trabecular meshwork (filtration membrane of the aqueous fluid exit pathway) and reroutes aqueous from the anterior chamber directly into canal of Schlemm and out of the eye. It lowers the intraocular pressure (IOP) by increasing the outflow of fluid from the eye from the micro-bypass. In angle closure, the lens has to be removed to create enough space for the iStent to be inserted. | Device | phacoemulsification and iStent |
Primary outcome
Change in Intraocular Pressure Between Baseline and 1 Year
Time frame: 1 year
change in mean unmedicated intraocular pressure between baseline and 1 year
1 secondary outcome
Change in Glaucoma Medications
Time frame: 1 year
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 31 Oct 2018.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 22814041Craven ER, Katz LJ, Wells JM, Giamporcaro JE; iStent Study Group. Cataract surgery with trabecular micro-bypass stent implantation in patients with mild-to-moderate open-angle glaucoma and cataract: two-year follow-up. J Cataract Refract Surg. 2012 Aug;38(8):1339-45. doi: 10.1016/j.jcrs.2012.03.025.
- Background: PubMed 20202537Fea AM. Phacoemulsification versus phacoemulsification with micro-bypass stent implantation in primary open-angle glaucoma: randomized double-masked clinical trial. J Cataract Refract Surg. 2010 Mar;36(3):407-12. doi: 10.1016/j.jcrs.2009.10.031.
- Background: PubMed 26147908Malvankar-Mehta MS, Iordanous Y, Chen YN, Wang WW, Patel SS, Costella J, Hutnik CM. iStent with Phacoemulsification versus Phacoemulsification Alone for Patients with Glaucoma and Cataract: A Meta-Analysis. PLoS One. 2015 Jul 6;10(7):e0131770. doi: 10.1371/journal.pone.0131770. eCollection 2015.
- Background: PubMed 20828829Samuelson TW, Katz LJ, Wells JM, Duh YJ, Giamporcaro JE; US iStent Study Group. Randomized evaluation of the trabecular micro-bypass stent with phacoemulsification in patients with glaucoma and cataract. Ophthalmology. 2011 Mar;118(3):459-67. doi: 10.1016/j.ophtha.2010.07.007. Epub 2010 Sep 15.
- Individual participant dataSharing planned: Undecided
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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.
Philemon Huang, MMed, FAMS principal investigator
National Healthcare Group, Singapore
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing iStent implantation in people with Primary Angle-Closure Glaucoma and Primary Angle Closure Without Glaucoma Damage, run by Khoo Teck Puat Hospital at 1 site in Singapore.
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 5 inclusion and 8 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 31 Oct 2018. 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 Singapore. 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?
Yes. Results are posted in the registry (first posted 2 Oct 2018). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
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?
Change in Intraocular Pressure Between Baseline and 1 Year (time frame: 1 year). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT03647033, which also lists 4 linked publications.
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 31 Oct 2018; AzTrials last refreshed its copy on 27 Oct 2026.