A. Micropulse diode laser console B. Slit lamp attachment/Setup C. Diagram to show the area of laser application to the trabecular meshwork (drainage channel of the eye).
Patient Information on:
Micropulse Diode Laser Trabeculoplasty (MDLT)
Glaucoma is a progressive and lifelong disease of the optic nerve with, mostly, raised intraocular pressure. Glaucoma is potentially blinding if left untreated or if treatment is delayed. Glaucoma could be managed by various means, including eye drops, Lasers and various glaucoma drainage surgeries. This information is designed to help you not only to decide about this laser procedure but also make you aware what to expect.
Clinical indications of MDLT
The current options available to treat Ocular Hypertension & Open Angle Glaucoma are limited to methods of lowering IOP which include medical, laser and surgical treatments. If medications are not appropriate, ineffective, if there is intolerance or allergy to eye drops, where eye drops could not be instilled due to physical limitations laser and other surgical procedures could be of value in controlling the pressure and preventing further loss of vision. Various management options of glaucoma are designed to do one of two things:
• Decrease the amount of fluid production in the eye
• Improve the fluid outflow out of the eye
MDLT is one option for lowering eye pressure by improving the drainage of fluid out of the eye for patients who have raised eye pressure (either for Glaucoma or for Ocular Hypertension with high risk of Glaucoma) and open-angles on gonioscopy. This laser treatment is also used in combination with drug therapy and may be able to delay or avoid the need for more invasive glaucoma surgery. It is a flexible treatment option and can be repeated if necessary, depending on the individual patient's response.
MDLT laser treatment could be used in the following scenarios:
This procedure is aimed to better manage your glaucoma or ocular hypertension and not to improve or restore lost sight.
Vision once lost from glaucoma can not be regained. All treatment/operation for glaucoma is aimed at slowing down the rate of progression of glaucoma so that the risk of complete blindness in one's lifetime may be reduced.
Micropulse Diode Laser Trabeculoplasty (MDLT): How it works
Trabecular meshwork is regarded as the drainage tissue of the eye and is situated around the periphery of the iris (inner side of the junction of black and white of your eye) and this is where fluid drains out of the eye. This meshwork is treated directly with the laser to improve drainage through it. MDLT does not rely on medicines, instead, uses an advanced laser system with short pulses of relatively low energy to target only the melanin-rich cells in the drainage channel (Trabecular meshwork) of the eye. This allows for only these cells to be affected, leaving surrounding tissue intact. This gentle laser treatment induces a response from the body in which white cells are released to clear the affected cells and rebuild the meshwork so that it again functions effectively. Essentially, your body’s own healing response (activated by MDLT) helps lower the pressure in your eye.
Stopping certain eye drops before MDLT laser treatment
If you are taking certain anti-glaucoma drops, they may interfere with the effectiveness and success of the MDLT laser treatment. Therefore, you will be asked to stop them for at least 4 weeks prior to the MDLT laser treatment and not to use them after the laser treatment. The drops you will be asked to stop are: Latanoprost 0.005% (Xalatan); Bimatoprost 0.01% 0r 0.03% (Lumigan); Tafluprost (Saflutan) or Travaprost 0.004% (Travatan). Some of these might be in combination with other drops; you will be advised to modify them appropriately as well.
The MDLT treatment procedure
Treatment takes place in the outpatient department (Eye Clinic at Russells Hall Hospital). A nurse will check your vision and you will be seen by an eye doctor who will put some drops into your eye to make your pupil small and to prevent and blunt the pressure spiking effect of the laser. These drops might take up to half an hour to work and may cause temporary brow ache and headache. The doctor will also take your written consent and explain further if you have any questions. Once seated in front of the laser machine (image B above), which looks similar to the slit lamp microscope you will have been examined on in clinic, you will have anaesthetic drops put in to numb the front of your eye.
It is very important for you to be seated comfortably with your chin on the chin rest and forehead pressed against the forehead band of the machine and also to stay relaxed and still during the laser procedure. Any movement might defocus the laser and it may not work as well as it should.
A special lens will then be placed against the front surface of your eye. This is not painful, but it might feel a little strange and rarely in some cases may cause some redness or irritation. During the laser treatment, you might see some flashes of light and hear clicking noises. Most patients tolerate the laser treatment well, but some might feel slight discomfort. The procedure takes between 15 to 20 minutes but the whole visit might take up to a few hours.
The doctor will put some more pressure lowering drops at the end of the laser procedure and will recheck your eye pressure about an hour later. We will make an appointment for you to come back to the clinic, usually a day later, a month later and 3-6 months after that. This follow-up appointment is to check your eye pressure and that your eye is settling. You are not advised any post-laser eye drops.
Potential side effects
MDLT laser is regarded as a safe and effective treatment; however, there may be some uncommon side effects.
Your vision may be blurred for a few hours but the chance of your vision being permanently affected from MDLT is extremely small. If you are concerned that your vision is not returning to normal, please contact the eye casualty. Complications are minimal but may include inflammation, unstable eye pressure, blurred vision, headache, iritis, corneal oedema, conjunctivitis, or eye pain. You are also advised not to drive yourself to the hospital, as you may be unable to drive home. It is possible for the pressure in your eye to increase immediately after the treatment but this is well anticipated and managed with specific eye drops
Studies show about 75% (3 out of 4) success rate for MDLT, with most patients responding well to the treatment, but others not responding at all. Usually, we cannot predict how well the laser will work as your response is determined by the type and severity of glaucoma you have and the basic make-up of your eye. It might take from few weeks to few months to see the response of the MDLT laser. You might require additional laser treatment 3-6 months later to lower the pressure if it is not sufficiently low after your first laser treatment.
There is usually a ‘loss of effect’ of the laser treatment. That is, the effects of the laser treatment might wear off in time – about half of all treatments stop working after five years, but the treatment can be repeated as required. You might still need to take some pressure lowering drops.
If you have any of the following the above laser treatment (MDLT):
Please contact your local eye A&E service team, the relevant contact number at Russells Hall Hospital is:
Tel. 01384 456111 Ext. 3633
For private patients & referrals
Mr Akash Raj
Consultant Ophthalmologist, Glaucoma specialist & Cataract surgeon
(Alternate Thursday AM)
01384 632 640
Private Secretary: Liz Carter : 01384 632 636
Fax: 01384 632702
FAO Liz Carter
Mr Akash Raj
Consultant Ophthalmologist, Glaucoma & Cataract specialist
For NHS Referrals through GP/Opticians
Mr Akash Raj
Consultant Ophthalmologist (Glaucoma Lead)
Extn. 5815 (NHS Secretary: Lyn Eaton)
FAO Lyn Eaton