The iStent is one of a range of procedures known as “Minimally Invasive Glaucoma Surgery (MIGS)”. It is a small (1mm long) titanium tube that is implanted into the eye to lower intraocular pressure and reduce the need for eye drops in patients with ocular hypertension or primary open angle glaucoma.
The iStent is inserted into the eye’s natural drainage channel – the trabecular meshwork. The aqueous humour is then able to bypass the trabecular meshwork and drain through the iStent lowering the eye pressure (IOP) as well as the need for glaucoma eye drops. Insertion of the iStent involves a short surgical procedure that is often performed at the same time as cataract surgery, usually as a day case procedure. The implantation of the iStent only adds an addition 5-10 minutes to the surgical time of the cataract surgery. The operation is usually performed under local anaesthetic using eye drops to numb the eye (topical anaesthesia).
The success rate for this treatment is very promising. A large randomised study in the USA, involving almost 500 patients, randomly assigned patients to have cataract surgery alone or cataract surgery with iStent. 76% of patients treated with the Stent had at least a 20% reduction in IOP compared to 60% of those having cataract surgery alone at 2 years.
The iStent is made from non-magnetic titanium, the same material used for replacing heart valves so it will not cause an allergic reaction or be rejected by the body. As it is non-magnetic it is safe for you to have an MRI scan in the future if needed. The iStent will not set off airport scanners.