Laser Iridectomy for narrow angle or angle closure glaucoma or risk of glaucoma
This article contains the information about the reasons, conditions, results, risks and limitations of the laser iridectomy as a treatment for narrow angle or angle closure glaucoma or risk of glaucoma.
WHY LASER THERAPY?
The angle between the cornea and iris is the area where the liquid produced in the eye (the aqueous) is evacuated. If this angle is closed, this liquid is not drained properly. This leads to an increase of the pressure inside the eye that damages the nerve fibres of the retina and the optic nerve. This condition may occur in some hours of time. Pain and loss of vision, often irreversible and some-times an anatomical dis-organisation of the eye may follow.
The laser iridectomy is the most appropriate way to prevent this condition.
THE LASER TREATMENT
The laser beam uses a light capable of carrying a large amount of energy that is delivered to a specific area of the iris in order to create a hole allowing a recirculation of the aqueous that widens the angle.
The session is performed on an outpatient basis. Anesthesia of the eye is obtained by the instillation of anesthetic drops. The patient sits in front of the laser engine. Laser impacts are applied through a lens placed on the eye. The whole pro-cedure time does not exceed ten minutes per session. It is painless.
The treatment is carried out in one or two sessions spaced by several days to several weeks.
In the vast majority of cases, treatment is well tolerated. The patients leaves the Eye Clinic immediately after treatment and resumes usual activities.
The eye care is reduced to the instillation of drops and / or taking pills as indicated by the ophthalmologist.
In most cases, a durable or permanent opening of the angle is achieved. The success rate is very high.
Controls will be necessary at dates proposed by the ophthalmologist.
COMPLICATIONS OF THE TREATMENT
The non serious complications are:
Dazzle, due to the microscope light, can be felt throughout the examination.
Conjunctival bleeding due to the contact lens: rare, benign, disappears in few days.
Arterial hypotension may occur in susceptible individuals. It will quickly disappear when lying down.
Irritation of the cornea (superficial keratitis): It is a rare hazard, occurring in less than 1% of the cases. Promptly treated, it cures generally in 24 to 72 hours.
Moderate elevation of the eye pressure: it is frequent and systematically preventively treated.
Iris bleeding: It is a frequent, unpredictable, always transient, hazard. It may cause a visual veil during a few hours.
These incidents are of no concern. If the patient is prone to arterial hypotension, it is necessary to get the ophthalmologist informed.
Severe complications of this type of laser photocoagulation are so exceptional that they are neither predictable nor quantifiable.
Severe elevation of the eye pressure: rare, may cause blurry vision, eye pain, headache. If treated promptly, within the hours of the beginning of the symptoms, it resolves rapidly without sequels.
Macular oedema: It is a distant reaction to laser impacts that leads to the accumulation of water in the centre of the retina. It may be responsible of a loss of details vision, lasting a few weeks to several months, sometimes permanently. Although rare, it is systematically preventively treated.
Retinal detachment. It is a very rare distant reaction to the impacts. It requires delicate surgery of replacement of the retina.
Misplaced impact, reaching the middle of the centre of the crystalline lens or the retina. This incident can permanently reduce detail vision. It is extremely rare and occurs in restless, undisciplined pa-tients who do not control their eye movements and their bodies. To avoid this, the patient is asked to keep the most calm and compliance during this examination.
LIMITATIONS OF TREATMENT
This treatment is less effective if the iridocorneal angle is scarred due to previous crises of angle closure that can sometimes go unnoticed.
Like any living tissue, the iridocorneal angle can react in a variable way, immediately, months or years, after the treatment. This treatment cannot therefore claim to prevent, neither categorically nor permanently further increases of intraocular pressure, especially if other causes of ocular hypertension (vitreous or lens swelling, trabecular meshwork resistance etc.), are involved
Laser iridectomy does not preclude the use of eye drops nor surgery in the management of glaucoma.
THE PATIENT SHOULD CONTACT AN EYE DOCTOR IMMEDIATELY IN CASE OF
Pain, severe sensitivity to light, redness, tearing, secretions, swelling of the eyes or eyelids
Sharp decrease of the vision.
Perception of floaters with flashes of lightning, a black rain or a motionless large dark spot.
By courtesy of Dr. SAFFIEDINE, ophthalmologist in Playa De Las Americas.