In short: the Hydrus Microstent is a permanent 8 mm nitinol scaffold placed in your eye’s drainage channel (Schlemm’s canal) to lower intraocular pressure in mild-to-moderate open-angle glaucoma. It can be implanted on its own or, most commonly, at the same time as cataract surgery, and most patients reduce or stop their drops.
What is the Hydrus Microstent?
Glaucoma damages the optic nerve when fluid (aqueous humour) cannot drain freely and pressure inside the eye rises. In open-angle glaucoma the bottleneck is the trabecular meshwork. The Hydrus Microstent, made of nitinol — the same flexible nickel-titanium alloy used in heart and ophthalmic implants — is threaded through that meshwork and scaffolds about three clock-hours (90 degrees) of Schlemm’s canal, holding it open over several collector channels so fluid drains and pressure falls.
It is one of the best-studied minimally invasive glaucoma surgery (MIGS) devices in the UK. The HORIZON randomised trial showed that adding a Hydrus to cataract surgery left far more eyes medication-free than cataract surgery alone, with benefit sustained at five years and roughly half the need for further glaucoma surgery. Unlike a trabeculectomy, there is no external bleb and recovery is fast.
Your options
Your consultant will recommend the right approach after assessing the stage of your glaucoma, your target pressure and whether you also have a cataract.
Not sure which glaucoma procedure is right for you? A consultant assessment makes it clear.
Book your assessmentHow the procedure works
The Hydrus is implanted “ab interno” — from inside the eye, through a tiny clear-corneal incision, with no external wound or stitches in most cases. It is a day-case procedure under anaesthetic drops, sometimes with a small block.
Before — assessment
Your consultant confirms open-angle glaucoma with gonioscopy, OCT of the optic nerve and visual fields, and sets your target pressure. Suitability needs an open drainage angle.
In theatre — minutes
Under a microscope and a gonioprism lens, the pre-loaded Hydrus is tracked into Schlemm’s canal and deployed. If combined with cataract surgery, the lens is replaced first, then the Hydrus is placed.
Same day — home
You go home the same day with a clear shield and a course of antibiotic and anti-inflammatory drops. No eye patch is usually needed.
Recovery
Recovery is quick. Vision may be blurry for a few days and you’ll use drops for around four weeks. A day-1 check confirms the pressure is settling. Most patients are back to light activities within a day or two and to full activity within 1–2 weeks. You can usually drive once your vision meets the legal standard and your surgeon is happy. Glaucoma needs lifelong monitoring even when pressure is well controlled, so reviews continue every few months.
Cost
At our partner clinics across southern England, a standalone Hydrus Microstent procedure is typically £4,500–£6,800 per eye. When added at the same time as private cataract surgery it is usually a £3,200–£4,800 supplement, because you are already in theatre. Quotes include the device, your consultant glaucoma surgeon, theatre and routine follow-up. Many patients spread the cost with 0% finance. Book a consultation from £240 for a personalised quote, or see our full price list.
Frequently asked questions
How much does private Hydrus Microstent surgery cost in the UK?
At our partner clinics in southern England, a standalone Hydrus Microstent MIGS procedure is typically £4,500–£6,800 per eye as a day case. When the Hydrus is added at the same time as private cataract surgery it is usually a £3,200–£4,800 supplement, because you are already in theatre. Quotes include the device, your consultant glaucoma surgeon, theatre and routine follow-up. Book a consultation from £240 for a personalised quote.
Will the Hydrus get me off my glaucoma drops?
Many patients reduce or stop their drops. In the HORIZON trial, 78% of eyes that had a Hydrus combined with cataract surgery were medication-free at 24 months, compared with 48% after cataract surgery alone. Your final regimen depends on the pressure achieved and your individual target, and lifelong monitoring continues even when drops are stopped.
How does the Hydrus compare to the iStent and other MIGS?
The Hydrus is an 8 mm nitinol scaffold that both bypasses the trabecular meshwork and props open about three clock-hours of Schlemm’s canal. In the head-to-head COMPARE trial it achieved a higher rate of medication-free pressure control at 12 months than two iStent devices. Both are safe, effective canal-based options; the right choice depends on your anatomy and your surgeon’s assessment.
Is Hydrus surgery painful, and is it safe?
It is performed under anaesthetic drops, sometimes with a small block, so most people feel pressure and see lights rather than pain. It adds only a few minutes to cataract surgery. The most common issues are a small bleed in the front of the eye (hyphaema) or a short-lived pressure spike, which usually settle. Serious complications are uncommon compared with traditional trabeculectomy.
When can I drive, work and fly after a Hydrus?
Most patients return to light activities within a day or two and to full activities within 1–2 weeks. Vision can be blurry for a few days while a four-week course of drops is used. You can usually drive once vision meets the legal standard and your surgeon is happy, and short-haul flying is generally fine within a week or so.
Does private insurance or the NHS cover the Hydrus?
Bupa, AXA Health, Aviva, Vitality and WPA may cover MIGS when it is clinically indicated, subject to your policy terms and pre-authorisation — we provide the procedure and device codes your insurer needs. The Hydrus is also available on the NHS in selected cases, but waiting times and device choice vary; self-pay gives you faster access and choice of surgeon.