Laser treatment for retinal disorders
WHY LASER THERAPY?
Because the following conditions may lead to visual, sometimes permanent, loss of vision for which laser treatment is one of the most appropriate treatments:
* Rip or hole in the retina: The presenting symptoms of this lesion are usually the perception of recurrent lightning, “black rain”, floating spider web, threads, flies or dots. Sometimes the lesions are discovered fortuitously during a routine ophthalmological checkup. The goal of treatment is to create a solid scar around the lesion in order to prevent a retinal detachment. In some conditions, a more extended treatment, such a 360º circular dam, may be proposed.
* Diabetic retinopathy: After several years of evolution, diabetes may cause significant disorders in the retinal circulation. Diabetic lesions may be responsible for severe visual loss and, in extremis, to a complete anatomical disorganization of the eyeball. Laser treatment can be proposed to treat individual lesions. If there is a risk of bleeding in the vitreous, an extended treatment of large areas of the retina (pan photocoagulation) may be proposed.
* Macular edema: Occurs in age related macular degeneration, lens implanted eyes, myopic degeneration of the central area of the retina etc. Laser treatment aims to dry the lesion and to stabilize the vision.
* Other retinal diseases: Retinal vein occlusion, eye tumor, angiomatosis, macro aneurysm, central serous chorio-retinopathy, etc.
THE LASER TREATMENT
The laser beam uses rays of light that carry a large amount of energy to be delivered in a specific location of the eye. It can coagulate abnormal vessel, destroy tissues and create a scar.
The laser treatment is performed on an outpatient basis after the pupils have been dilated by the instillation of eye drops.
Anaesthesia of the eye is obtained by the instillation of anesthetic drops. The patient sits in front of the laser machine. Laser impacts are applied with or without interposition of a lens placed on the eye. The whole procedure time does not exceed 20 minutes per session.
When the lesions are numerous or extensive, the treatment is carried out in several sessions separated by several days to several weeks.
In the vast majority of the cases the treatment is well tolerated. The patient leaves immediately after treatment and resume normal activities.
There is no specific eye care after the laser treatment. In specific cases, the ophthalmologist prescribes anti-inflammatory eye drops.
Control will be necessary at a date stated by the ophthalmologist.
COMPLICATIONS OF THE TREATMENT
The mild complications are:
* Glare, due to the laser session itself and to pupil dilation, will be felt throughout the examination and lasts 2 hours. It is advisable to have sunglasses when leaving the Eye Clinic and not to drive as long as this glare is noticeable.
* Arterial hypotension may occur in susceptible individuals. It disappears quickly by lying down.
* Extended pupil dilation, lasting several days. It is annoying by the glare it induces. This risk is unpredictable and very rare.
* Pain: Retinal laser photo-coagulation causes very little or no pain. Laser impacts may be painful if the retina is inflamed. In such a case, the parameters of the impacts are adjusted to reach the effective and most tolerable level.
* 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.
* Alterations to the peripheral visual field. They are inevitable, inherent to the effect of the treatment.
* Conjunctival bleeding due to the contact lens: rare, benign, disappears in few days.
These incidents are of no concern. If the patient have experienced any of them in previous similar conditions, it is advised to report them to the Eye Doctor.
The severe complications of retinal laser photocoagulation are rare:
* Alterations to the medial and central visual field. They occur, inevitably, when the laser impacts must be placed in the center or on the mid periphery of the retina. They can impede, immediately or a few days to years after the laser treatment, good peripheral vision such as driving a car, especially in night conditions.
* Macular edema: This hazard is due to the accumulation of water in the center of the retina. It is a distance reaction to laser impacts and is responsible of a loss of the detail vision, lasting a few weeks to several months, sometimes permanently. It can occur especially in chronically poorly treated diabetics where the treatment has to be extensive, covering the entire mid and peripheral retina. Its risk is less than 1%.
* Crisis of acute glaucoma. This risk is inherent to all dilation of the pupils. It is exceptional and not quantifiable.
* Misplaced impact, reaching the middle of the center of the retina. This incident can permanently reduce details vision. It is extremely rare and occurs in restless, undisciplined patients 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 THIS TREATMENT
In most cases, lasting healing of the lesion is achieved.
It is often necessary to repeat the treatment in order to consolidate it.
This treatment does not prevent the appearance of other lesions, especially in chronically poorly controlled diabetes.
This treatment does not allow recovery of visual acuity. At most, it can prevent a possible additional fall of the visual acuity. It is impossible to quantify the rate of the stabilization of the vision because the success depends on the location, extent, depth and aggressiveness of the lesions. These factors are too variable to allow statistical studies.
PRECAUTIONS TO BE TAKEN
Shocks of the head and rubbing the eyes should be avoided until healing is complete.
A change in the Aspirin or blood thinners treatments may be requested from your Family Doctor.
If in doubt, please ask your ophthalmologist for additional information.
YOU SHOULD CONTACT YOUR OPHTHALMOLOGIST 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.