Glaucoma

Glaucoma is the leading cause of irreversible blindness in the world. It is caused by too much fluid between the cornea and the iris. The excessive pressure crushes the optic nerve. Various treatments for the disease already exist.

Primary open-angle glaucoma: Primary open-angle glaucoma, the most common and inherited form, affects about 1.5% of the population. It is a chronic progressive optic neuropathy in which intraocular pressure is a relative risk factor. In about 30% of these glaucomas, the pressure is normal or even below the norm.

Angle closure glaucoma: The space between the cornea and the iris is usually sufficient to keep the angle between the two, or iridocorneal angle, open at all times. However, in some cases, such as in some hyperopic people, the angle becomes narrower and narrower as time passes. This can lead to the closure of the angle, causing a sharp increase in intraocular pressure and what is known as acute glaucoma. The mechanism is actually more complex than that. In most cases, acute glaucoma can be prevented by a laser procedure called iridotomy (hole in the iris).

Secondary glaucoma: There are many different forms of secondary glaucoma (ex. due to eye inflammation, infection, injuries, topical medication) and most of them require specific treatments. It follows that the treatment of glaucoma will depend primarily on the type of glaucoma the patient is affected by.

Medical treatment of glaucoma

Various anti-glaucoma medications (eye drops) are instilled into the eye daily. It is important to use them every day in order to maintain a stable low pressure and to avoid progression of glaucoma.

These drops are prescribed by the doctor, the treatment is personalised and adapted to each stage of the disease and to the patient's tolerance. More than 30 different eye drops or combinations of treatments are available. These medications work by different mechanisms, either by reducing the production of aqueous humour inside the eye or by increasing the outflow through the trabeculum or the uveoscleral pathway, thus decreasing the intraocular pressure.

Laser treatment of glaucoma
  • SLT, Selective Laser Trabeculoplasty

This is a low-energy laser treatment designed to stimulate the eye's drainage system, the "trabeculum". It is low-risk and can be performed during the consultation, painlessly and often reduces eye pressure and sometimes even allows patients to stop taking medication. Known as Selective Laser Trabeculoplasty, SLT is a highly effective procedure for reducing intraocular pressure. This treatment is performed in your ophthalmologist's office and usually takes no more than five minutes.

How does the SLT work?

The laser stimulates a natural healing process in the body. Short, low-energy pulses target the melanin or pigment in specific cells of the eye. In response, the healing mechanism will rebuild these cells. This process of cell regeneration increases drainage and contributes to the lowering of eye pressure.

Is SLT painful?

No, SLT is not painful and there are no side effects to worry about

What happens during the procedure?

The SLT treatment takes only a few minutes. Before the treatment, your ophthalmologist will give you drops to prepare your eye and give you a mild anaesthetic. Then, light laser pulses are delivered through a slit lamp, a specially adapted microscope.

Who can benefit from a SLT?

If you fit one of the following categories, you are a good candidate for an SLT.

if you have open angle glaucoma, pseudoexfoliation or pigmentary glaucoma (if you are not sure, ask your ophthalmologist)

if you are intolerant to anti-glaucoma medication or have difficulty taking it as prescribed.

if you have started a therapeutic anti-glaucoma treatment and want to combine it with an SLT.

if it is difficult for you to ensure regular follow-up treatment for financial, transport or other reasons.

  • Peripheral Iridoplasty with YAG laser

This laser is used to create a micro-perforation of the iris. This widens the iridocorneal angle in patients with narrow angle or closed angle glaucoma. This can reduce the risk of future glaucoma and prevent acute glaucoma attacks.

  • Peripheral Iridotomy with ARGON Laser

This technique is used when the angles remain narrow despite a peripheral iridotomy. It helps to reduce the size of the peripheral iris by moving it away and preventing contact with the trabeculum. This is the primary cause of damage to the trabeculum.

Surgical treatments

Trabecular pathway

The trabeculum is the main drainage pathway in the eye. It is a 360 degree "natural or physiological" channel encircling the iris tips. Surgical treatments consist in increasing the reduced capacity of the drainage function. Depending on the specific needs of the patient, we may consider either the implantation of a stent in a part of the trabeculum (iStent), a dilatation of the entire canal (canaloplasty ab interno), a surgical opening of the inner wall of the canal in the case of more advanced disease (GATT), or a combination of these micro-invasive procedures. These new operations are grouped under the acronym MIGS for "Microinvasive Glaucoma Surgery Techniques".

  • AB INTERNO CANOPLASTY

This is a procedure whereby a 250-micron microcatheter illuminated by a fibre optic is introduced into the trabecular system allowing a 360° treatment of the entire drainage system. This device passes through a precise incision in the cornea and then through a small opening in the trabeculum. With this microcatheter, a controlled injection of a viscoelastic gel into the canal is performed, which allows the defective drainage system to be reactivated and the ocular pressure to be reduced, without the need for an implant in the eye. The natural anatomy of the eye is preserved.

The trabeculum can function again, reducing pressure and the need for eye drops. This procedure can be combined with cataract surgery.

  • CORCONFERENTIAL TRABECULOTOMY & SUTURE 

This is a procedure similar to that of an ab interno canaloplasty, where the inner wall of the trabeculum or the entrance to the system is opened. In this way, the greatest resistance of the drainage channel is removed. This results in a much higher pressure drop. This procedure is performed in cases of advanced disease.

This procedure can be combined with a cataract extraction or performed independently. It maintains the natural anatomy of the eye without the need for a permanent implant or stent in the eye.

Dr Sharkawi was the first surgeon in Switzerland to perform this procedure and the first in Europe to perform it on children. He is one of the most experienced surgeons in the world with this technique. He teaches the procedure to other surgeons in Europe, the USA and Africa.

  • I-STENT (TRABECULAR BYPASS)

Insertion of a 1mm Titanium micro stent into the trabeculum which acts as a tube diverting fluids into the deeper layers of the drainage system and bypasses the major site of resistance contributing to the pressure drop as well as the number of useful drops.

The iStent can either be implanted alone or in combination with cataract surgery. It is a minimally invasive procedure that does not distort the anatomy of the eye and has an extremely safe profile.

Subconjunctival route

This is a standard drainage route that has been used for many years by glaucoma surgeons. A trabeculotomy is performed when the trabecular drainage system is non-functional.

  • ADJUSTABLE TRABECULECTOMY

The aqueous humour is diverted directly into the subconjunctival space from the anterior chamber by creating a small opening in the sclera (white of the eye). Modern techniques use adjustable sutures to allow individualised drainage. The tension of the sutures can be adjusted in the postoperative period by the surgeon in the office to achieve adequate tension in gradual steps.

This approach reduces the number of hypotonic (low pressure) complications associated with older techniques.

Anti-scarring medication is used to achieve long-term pressure reduction.

  • PERSERFLO IMPLANT

The Perserflo implant uses a procedure similar to trabeculotomy with the addition of a drainage system at the mid-upper subconjunctival level to divert the aqueous humour directly, reducing operative time and vision recovery time. This approach is less invasive as it does not require an incision in the sclera or subconjunctiva. A discussion with the surgeon is then useful to estimate the best individual approach.

  • XEN IMPLANT

The Xen implant, uses a procedure similar to trabeculotomy with the addition of a stent to divert the aqueous humour directly into the subconjunctival space, reducing operative time and time to recovery of vision. This approach is possible at all stages of the disease and a discussion with the surgeon is then useful to estimate the best individual approach.

  • BAERVELDT TUBE

These drainage tubes are used when trabeculotomy or other subconjunctival procedures are deemed to be at high risk of failure or have already failed. It is a larger implant that diverts fluid into the posterior conjunctiva of the eye. Thanks to modern techniques, this is a very safe procedure.

Dr. Sharkawi has introduced several new surgical techniques, which have been published, that make operations safer and more effective compared to traditional techniques. He is the most experienced in Baerveldt tube implantation in complex adult glaucoma and in paediatric cases.