The Baerveldt tube aims to reduce the pressure inside the eye and therefore prevent or slow down further damage to the optic nerve. It will not cure your glaucoma, reverse any damage already caused by glaucoma, or bring back any lost vision. An aqueous shunt may be an appropriate course of action for patients for whom drop treatment has been ineffective or is unsuitable, or a previous surgery has not succeeded in controlling intraocular pressure. It may also be recommended as the first course of action in your glaucoma treatment. Ultimately it is a decision to be reached after discussing your condition and its progression with us.

Fluid called aqueous humour is naturally produced within the eye and drains away through a complex sponge-like network called Trabecular meshwork. Glaucoma is the result of a build-up of this fluid caused by a blockage of the natural drainage channels of the eye. This pressure can damage the optic nerve which carries images from the eye to the brain, affecting your vision. Like Trabeculectomy surgery (the traditional Glaucoma surgery), the Aqueous shunt drains fluid from inside the eye to a pooled reservoir under the conjunctiva forming a ‘bleb’. This bleb will stay as long as the fluid is draining.

Most glaucoma surgical studies examine success rates over a five year period. With aqueous shunts such as the Baerveldt, the expected success rate over five years is now between 70 and 80 per cent. Although a sizeable proportion of patients achieve good pressure control without the need for continued glaucoma medication, many patients still require some medication to assist the shunt in controlling the pressure. In such circumstances, the medication required is usually less than was required before the surgery.

Severe complications are uncommon but are most likely to happen if the eye pressure drops very low or very quickly in the early post-operative period. A very low or an abrupt drop in eye pressure can result in a choroidal haemorrhage (bleeding at the back of the eye). However, this happens in less than one per cent of cases. If the pressure drops very low it may be elevated again either using an injection of a viscoelastic gel or a gas into the eye in the clinic, or by a return to the operating theatre to have the tube adjusted.

Aqueous Shunt Implantation has grown in popularity in recent years as techniques and technology have improved, leading to better outcomes and patient safety. It is now frequently used as a first-line surgical treatment for glaucoma.

In broad terms, Glaucoma treatment can be separated into eye drops, lasers and surgery. Surgery is generally offered when the drops or laser you have been using or have not lowered the eye pressure enough, you are getting side-effects, or you find it difficult to use the drops.

You may be suitable for a laser procedure, or you may need more eye drops. However, this may not control your Glaucoma and your vision may continue to get worse.

Roughly five percent of aqueous shunt patients require a return to the operating theatre in the first month after surgery for adjustment, either because of low pressure or high pressure. As with all eye surgeries, there is also a very small chance of infection, requiring further treatment.