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GaslEss Macular Hole Surgery

GaslEss Macular Hole Surgery (GEM): a Feasibility Study

Status
Not yet recruiting
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06079593
Acronym
GEM
Enrollment
60
Registered
2023-10-12
Start date
2024-01-01
Completion date
2026-10-31
Last updated
2023-12-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Macular Holes

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: * Standard macular hole surgery with gas tamponade * Novel macular hole surgery without tamponade Gathering feasibility data to inform a future fully powered trial

Detailed description

The investigators 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. The investigators 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. The investigators will test their vision, examine their eyes, and ask participants to complete questionnaires about their treatment and vision. The investigators aim to examine if the technique appears safe and works well at closing macular holes. It will also inform if a larger clinical trial is possible.

Interventions

PROCEDUREGasless Macular hole surgery

Pars plana vitrectomy to treat full thickness macular hole, with internal limiting membrane flap and ophthalmic viscosurgical device covering

PROCEDUREStandard Macular hole surgery

Pars plana vitrectomy to treat full thickness macular hole, with internal limiting membrane peel, and C2F6 tamponade

Sponsors

National Institute for Health Research, United Kingdom
CollaboratorOTHER_GOV
King's College Hospital NHS Trust
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)

Masking description

Images will be graded in a masked fashion

Eligibility

Sex/Gender
ALL
Age
18 Years to 100 Years
Healthy volunteers
No

Inclusion criteria

* Requiring PPV to treat idiopathic (primary) FTMH. * 18 years or older * ETDRS BCVA letter score of 1 or better in the study eye * Able to provide written informed consent

Exclusion criteria

General: * Hypersensitivity to hyaluronate or other components of Healon Pro® viscoelastic * Any major illness or major surgical procedure within 4 weeks * 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 * Previous vitreoretinal surgery, retinopexy, open-globe injury, or endophthalmitis * Presence of fibrotic retinal proliferation or central epiretinal membrane (within 1 disc diameter of the fovea) * Aphakia * Current or former myopia greater than 6 dioptres * Current or previous posterior uveitis or choroiditis * Presence of other ocular co-morbidity that, in the opinion of the investigator, is likely to impair BCVA postoperatively or affect FTMH closure * Current ocular or periocular infection, other than mild or moderate blepharitis * Lens or media opacity that preclude adequate retinal assessment and imaging

Design outcomes

Primary

MeasureTime frameDescription
Feasibility: Screen failure36 monthsProportion of those screened who are randomised
Feasibility: Recruitment rate36 monthsRecruitment rate (participants per site per month)
Feasibility: Participant retention6 monthsProportion reaching month 6 milestone visit
Feasibility: Cross-over36 monthsProportion converting to standard vitrectomy with gas, due to inability to seal the FTMH, or detection of peripheral retinal breaks

Secondary

MeasureTime frameDescription
Safety outcomes: Intra- and post-operative complications6 months
Safety outcomes: Development or progression of lens opacity6 monthsWithin 6 months of vitrectomy (proportion undergoing or listed for cataract surgery and mean change in Lens Opacities Classification System 2 \[LOCS2\] grading)
Efficacy Outcomes: Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA)6 monthsMean change from baseline
Patient reported outcomes measures: National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ25; composite score)6 months
Patient reported outcomes measures: Qualitative analysis6 monthsAnalysis of participant feedback
Patient reported outcomes measures: Participant acceptability of the intervention6 monthsAssessed by the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ; composite score)
Efficacy Outcomes: Surgical success3 monthsProportion 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 events6 months

Contacts

Primary ContactGeorge Murphy, MB BCh BAO, FRCOphth
george.murphy4@nhs.net(+)44 2032991297 ext 31297

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026