What Is Minimally Invasive Glaucoma Surgery?
Glaucoma is a group of eye conditions in which the optic nerve becomes progressively damaged, often, though not always, in association with raised intraocular pressure (the fluid pressure inside the eye). Because the damage to the optic nerve cannot be reversed, treatment focuses on lowering eye pressure to slow or halt further loss of vision. According to NICE, treatment usually begins with eye drops or laser therapy, with surgery considered where pressure control remains inadequate or the condition is advanced.
Minimally invasive glaucoma surgery is a surgical treatment, but it is deliberately less invasive than traditional glaucoma operations such as trabeculectomy or tube (drainage device) surgery. Most MIGS procedures are carried out through the small incisions already used in cataract surgery, and they work by improving the eye’s natural drainage of fluid. Depending on the technique, this may involve:
- inserting a very small stent to bypass a blocked area of the eye’s natural drainage channel (the trabecular meshwork)
- gently opening, dilating or removing part of the drainage channel to improve outflow
- creating an alternative drainage route to allow fluid to leave the eye more easily
Who May Benefit From Minimally Invasive Glaucoma Surgery?
Suitability depends on the type and stage of your glaucoma, your current eye pressure, the health of your optic nerve and the anatomy of your eye. Minimally invasive glaucoma surgery may be considered if you:
- have mild to moderate open-angle glaucoma or ocular hypertension that is not adequately controlled
- are due to have cataract surgery and also require better pressure control
- struggle with eye drops because of stinging, redness, allergy, dry eye or difficulty instilling them
- find it hard to remember or physically manage a daily drop routine
- have had a partial response to laser treatment such as selective laser trabeculoplasty
- wish to explore options before considering more invasive filtration surgery
MIGS is generally less suitable where glaucoma is advanced, where very low target pressures are needed, or where the drainage angle is closed or scarred. In these situations, trabeculectomy, a drainage implant or other treatment may be recommended instead. Your clinician will advise based on your assessment.
Conditions and Problems It May Address
- primary open-angle glaucoma
- ocular hypertension (raised eye pressure without established nerve damage)
- pigmentary and pseudoexfoliative glaucoma, in selected cases
- eye pressure that remains above target despite maximum tolerated drops
- intolerance of, or difficulty with, topical glaucoma medication
- coexisting cataract and glaucoma affecting vision and quality of life
Glaucoma is often symptomless in its early stages, which is why detection commonly occurs at a routine optician appointment. Symptoms that should prompt urgent assessment include sudden eye pain, redness, haloes around lights, nausea or rapid loss of vision, which may indicate acute angle closure.
Potential Benefits
Outcomes vary between individuals, and no procedure can guarantee a particular pressure level. That said, minimally invasive glaucoma surgery may:
- help lower intraocular pressure and support long-term glaucoma management
- reduce the number of pressure-lowering eye drops needed, or in some cases remove the need for them
- support stability of the optic nerve and help slow further visual field loss
- involve a shorter procedure and quicker visual recovery than traditional filtration surgery
- carry a lower risk of certain complications associated with more invasive glaucoma operations
- be combined with cataract removal, addressing two problems in one visit to theatre
- preserve the option of more extensive surgery in future, if it becomes necessary
Consultation and Assessment
A thorough assessment is essential before any decision is made. During your consultation with Ms Diana Urbaneja, you can expect:
- a discussion of your symptoms, general health, medication and family history of glaucoma
- measurement of your intraocular pressure and assessment of corneal thickness
- examination of the drainage angle (gonioscopy), an important step in confirming whether MIGS is technically possible
- detailed optic nerve imaging using OCT, along with visual field testing to map your peripheral vision
- assessment of the lens for cataract, and biometry measurements if lens replacement is planned
- an explanation of the realistic aims, risks, benefits and alternatives, including drops, laser, MIGS and conventional surgery
- a personalised plan with an agreed target pressure and monitoring schedule
You will have time to ask questions and consider your options before giving consent. Bringing a list of your current eye drops and tablets is helpful.
How the Procedure Is Performed
Minimally invasive glaucoma surgery is usually carried out as a day-case procedure in a hospital or surgical unit, meaning you go home the same day. Most patients have local anaesthetic, drops and an injection around the eye, so the eye is numb but you remain awake. Sedation can be discussed if you feel anxious.
During the operation
- the eye and surrounding skin are cleaned and a drape is applied
- very small incisions are made at the edge of the cornea
- if a cataract is being removed at the same time, this is done first and an intraocular lens is implanted
- using a specialised lens and microscope view of the drainage angle, the stent is placed or the drainage channel is treated
- the incisions are typically self-sealing and often require no stitches
The MIGS element commonly adds only a short time to a cataract operation. You will usually be in the unit for a few hours in total, and you must arrange for someone to take you home.
Recovery and Aftercare
Recovery varies from person to person. Vision is often blurred initially and may take several days to weeks to settle, particularly if surgery was combined with lens replacement. You will be given anti-inflammatory and antibiotic drops for a few weeks, and instructions about whether to continue, reduce or stop your usual glaucoma drops, never change these without advice.
General guidance after surgery
- avoid rubbing or pressing on the eye, and use a shield overnight if advised
- avoid swimming, dusty environments and heavy lifting or strenuous exercise until reviewed
- most people resume light daily activities within a few days
- driving should only resume once vision meets DVLA standards and your clinician agrees
- follow-up appointments are arranged to check pressure and healing, usually within the first day or week and again over the following months
Seek prompt medical advice if you develop increasing pain, marked redness, significant loss of vision or a discharge from the eye.
01
Consultation
Glaucoma assessment & imaging
02
Surgery
MIGS procedure, day case
03
Aftercare
Drops & pressure checks
Guide Price
At consultation
Per eye, including procedure, theatre and aftercare. See the pricing page for all options.
At a glance
Anaesthetic
Local
Procedure time
~30-45 min
Stay
Day case
Recovery
Up to 6 weeks
Follow-up
Regular pressure monitoring