GaslEss Macular Hole Surgery (GEM): a Feasibility Study
Study Details
Study Description
Brief Summary
Macular holes are a hole in the centre of the retina, the light-sensing layer in the back of the eye. They cause a central 'blind spot' in the vision, which can be very disabling for patients. Standard surgery involves injecting a large gas bubble inside the eye. This takes 4-8 weeks to leave the eye. During this time vision is greatly reduced in the eye. This limits patients' ability to drive and work. Gas causes clouding of the natural lens in the eye (cataract). The gas can also raise pressure inside the eye, causing pain and sometimes loss of vision. Patients cannot fly or have certain medicines until the gas absorbs.
Critically, most patients position face down for 50 minutes out of every hour for a week after surgery. This is to float the gas bubble onto the macula. Head positioning is particularly difficult. It very often causes pain in the neck, back, arms and legs. Rarely, blood clots can form in the legs and be life-threatening if they dislodge and travel to the lungs. Head positioning also places a large burden on those caring for the patient.
The gases are 'greenhouse' gases and cause damage to the environment, for about 3,200 years.
This study looks at a new surgical technique for treating macular holes. The new technique aims to make patients' recovery from surgery easier, and safer.
The purpose of this study therefore is to compare two treatments:
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Standard macular hole surgery with gas tamponade
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Novel macular hole surgery without tamponade Gathering feasibility data to inform a future fully powered trial
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
We are testing a new surgical technique, that does not use the gas bubble and face down positioning. Instead, a licensed surgical gel and thin flap of retinal tissue seal the macular hole. Early small studies suggest the new technique is safe and works as well as standard surgery.
We will invite 60 people with macular hole to take part in the study. Half will be randomly allocated to the new technique and half to standard surgery. All participants will return at regular intervals after surgery for review. We will test their vision, examine their eyes, and ask them to complete questionnaires about their treatment and vision.
We aim to examine if the technique appears safe and works well at closing macular holes. It will also inform us if a larger clinical trial is possible.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Gasless Surgery
|
Procedure: Gasless Macular hole surgery
Pars plana vitrectomy to treat full thickness macular hole, with internal limiting membrane flap and ophthalmic viscosurgical device covering
|
| Active Comparator: Standard surgery with gas tamponade
|
Procedure: Standard Macular hole surgery
Pars plana vitrectomy to treat full thickness macular hole, with internal limiting membrane peel, and C2F6 tamponade
|
Outcome Measures
Primary Outcome Measures
- Feasibility: Screen failure [36 months]
Proportion of those screened who are randomised
- Feasibility: Recruitment rate [36 months]
Recruitment rate (participants per site per month)
- Feasibility: Participant retention [6 months]
Proportion reaching month 6 milestone visit
- Feasibility: Cross-over [36 months]
Proportion converting to standard vitrectomy with gas, due to inability to seal the FTMH, or detection of peripheral retinal breaks
Secondary Outcome Measures
- Efficacy Outcomes: Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) [6 months]
Mean change from baseline
- Efficacy Outcomes: Surgical success [3 months]
Proportion with FTMH closure within 3 months, without further FTMH surgery
- Efficacy Outcomes: Area under the BCVA versus time curve (ETDRS letter score) [6 months]
- Safety outcomes: Adverse events [6 months]
- Safety outcomes: Intra- and post-operative complications [6 months]
- Safety outcomes: Development or progression of lens opacity [6 months]
Within 6 months of vitrectomy (proportion undergoing or listed for cataract surgery and mean change in Lens Opacities Classification System 2 [LOCS2] grading)
- Patient reported outcomes measures: Participant acceptability of the intervention [6 months]
Assessed by the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ; composite score)
- Patient reported outcomes measures: National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ25; composite score) [6 months]
- Patient reported outcomes measures: Qualitative analysis [6 months]
Analysis of participant feedback
Eligibility Criteria
Criteria
Inclusion Criteria:
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Requiring PPV to treat idiopathic (primary) FTMH.
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18 years or older
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ETDRS BCVA letter score of 1 or better in the study eye
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Able to provide written informed consent
Exclusion Criteria:
General:
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Hypersensitivity to hyaluronate or other components of Healon Pro® viscoelastic
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Any major illness or major surgical procedure within 4 weeks
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Any other condition that, in the opinion of the investigator, would prevent the participant from granting informed consent or complying with the protocol
Study eye
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Previous vitreoretinal surgery, retinopexy, open-globe injury, or endophthalmitis
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Presence of fibrotic retinal proliferation or central epiretinal membrane (within 1 disc diameter of the fovea)
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Aphakia
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Current or former myopia greater than 6 dioptres
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Current or previous posterior uveitis or choroiditis
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Presence of other ocular co-morbidity that, in the opinion of the investigator, is likely to impair BCVA postoperatively or affect FTMH closure
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Current ocular or periocular infection, other than mild or moderate blepharitis
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Lens or media opacity that preclude adequate retinal assessment and imaging
Contacts and Locations
Locations
No locations specified.Sponsors and Collaborators
- King's College Hospital NHS Trust
- National Institute for Health Research, United Kingdom
Investigators
- Principal Investigator: Timothy Jackson, PhD, FRCOphth, King's College London & King's College Hospital
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 204994