GaslEss Macular Hole Surgery (GEM)

GaslEss Macular Hole Surgery (GEM): a Feasibility Study

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

Study Overview

• Status: Not yet recruiting
• Conditions: Macular Holes
• Intervention / Treatment: Procedure: Gasless Macular hole surgery; Procedure: Standard Macular hole surgery

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.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: George Murphy, MB BCh BAO, FRCOphth; Phone Number: (+)44 2032991297 ext 31297; Email: george.murphy4@nhs.net

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / 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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Feasibility: Screen failure	Proportion of those screened who are randomised	36 months
Feasibility: Recruitment rate	Recruitment rate (participants per site per month)	36 months
Feasibility: Participant retention	Proportion reaching month 6 milestone visit	6 months
Feasibility: Cross-over	Proportion converting to standard vitrectomy with gas, due to inability to seal the FTMH, or detection of peripheral retinal breaks	36 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Efficacy Outcomes: Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA)	Mean change from baseline	6 months
Efficacy Outcomes: Surgical success	Proportion with FTMH closure within 3 months, without further FTMH surgery	3 months
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	Within 6 months of vitrectomy (proportion undergoing or listed for cataract surgery and mean change in Lens Opacities Classification System 2 [LOCS2] grading)	6 months
Patient reported outcomes measures: Participant acceptability of the intervention	Assessed by the Macular Disease Treatment Satisfaction Questionnaire (MacTSQ; composite score)	6 months
Patient reported outcomes measures: National Eye Institute 25-Item Visual Function Questionnaire (NEI VFQ25; composite score)		6 months
Patient reported outcomes measures: Qualitative analysis	Analysis of participant feedback	6 months

Collaborators and Investigators

• Sponsor: King's College Hospital NHS Trust
• Collaborators: National Institute for Health Research, United Kingdom
• Investigators: Principal Investigator: Timothy Jackson, PhD, FRCOphth, King's College London & King's College Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2024
• Primary Completion (Estimated): May 31, 2026
• Study Completion (Estimated): October 31, 2026

Study Registration Dates

• First Submitted: October 6, 2023
• First Submitted That Met QC Criteria: October 6, 2023
• First Posted (Actual): October 12, 2023

Study Record Updates

• Last Update Posted (Estimated): December 14, 2023
• Last Update Submitted That Met QC Criteria: December 8, 2023
• Last Verified: December 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Retinal Diseases; Retinal Perforations
• Other Study ID Numbers: 204994

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No