Retinal detachment. What is it?
The retina is a membrane that lines the walls of the eye inside. The images that arrive from the outside focus on the retina and it is responsible for transmitting them to the brain through the optic nerve.
Retinal detachment is the separation of the retina from the rest of the eye's layers, so that it stops working, causing loss of vision and, in case of detachment of the entire retina, complete blindness.
Why does it occur?
Some causes of retinal detachment may be the presence of scars inside the eye that pull from the retina, usually after intraocular bleeding; or inflammation caused by a tumor or intraocular metastasis, requiring a different treatment depending on the case.
Most retinal detachments are caused by the presence of one or more retinal tears or holes. These holes may appear due to thinning of the retina, which usually appears with age or myopia, or due to vitreous traction, caused by age, ocular inflammations or trauma.
The vitreous is a gelatinous fluid that fills the inside of the eye and is strongly attached to the retina in several places. When the vitreous shrinks, it pulls from these anchor points until it separates, being able to tear out a fragment of the retina, leaving a tear or retinal hole.
Once the retinal tear appears, the vitreous space fluid can pass through it and separate the retina from the wall of the eye, causing retinal detachment and consequent loss of vision.
What are the symptoms of retinal detachment?
The symptoms of retinal detachment are progressive absolute vision loss; that is, a black curtain appears that progressively covers the vision, from above or below, or from the side.
In some cases, alarm symptoms appear previously, such as the presence of abruptly flying flies or the appearance of light flashes associated with eye movement, as if they were lightning. These lightning usually means that the retina is being pulled, and may mean the appearance of the tear that subsequently causes retinal detachment.
How is your diagnosis?
The diagnosis is made by direct examination of the fundus by an ophthalmologist. It does not require additional tests. The detailed examination to assess the detachment and the surgical decision must be performed by a retina ophthalmologist.
Retinal detachment treatment
If the retina is repositioned in its normal place within a short period of time (days) from its appearance, it can recover some of the lost vision, or even all vision in some cases. If the detachment is not treated, a retinal atrophy, chronic ocular inflammation and, over time, atrophy of the entire eye (bulbi ptisis) that may be accompanied by pain hardly treatable with conventional analgesics can progressively appear.
The treatment is always surgical, with the aim of applying the retina to the wall, extracting the liquid between the retina and the wall and closing the causing hole, creating a scar on its edges. Depending on the case, it can be performed outside the eye (scleral surgery), from the inside (posterior vitrectomy) or both surgeries simultaneously.
When performed outside the eye, the wall is pushed into the detached retina by a silicone belt that is placed around the eye, below the extraocular muscles. If there is a lot of fluid between the retina and the eye wall, it can be removed by puncturing and squeezing it out of the eye. Finally the retinal hole is healed by freezing its edges through the eye wall. Depending on the case, a small gas bubble can be injected into the eye that expands and pushes the retina towards the eye walls temporarily while the retina heals, disappearing on its own after time.
If it is intervened from inside the eye, three incisions are made to access the interior and the liquid is aspirated through the retinal hole or, in complicated cases, creating new holes in the retina (retinotomies) The causing hole is healed by laser impacts around it. The retina is pushed towards the wall, replacing the vitreous gel with gas temporarily, or permanently in more complicated cases with silicone oil. Silicone oil may need to be removed after a few months by another surgery or it may be left indefinitely inside the eye.
Depending on the patient's state of health and the estimated duration of surgery, local or general anesthesia may be performed.
Prognosis after surgery
Recovery is progressive over the next 6 to 12 months, considering the final vision after one year of successful surgery. This recovery depends on many factors: the time of evolution, the area of detached retina, its location, the affectation or not of the central area of vision (macula), the presence of fibrous tissue that usually appears in long detachments evolution…
Depending on these factors, part of the vision can be recovered. However, not all retinal detachments can be reapplied, so you can continue to lose vision until you reach blindness.
Can retinal detachment be prevented?
The prevention of retinal detachment can be performed by routine fundus examinations by a retina specialist. In them degenerations are sought that can become tears, since many of them do not give any clinic. In this case, Argon laser could be treated urgently, to avoid its evolution.
The fundus should be annual for all those people who have an added risk factor, such as having a history of detachment in a close relative, suffering from myopia, flying flies, flashes or previous cataract surgery, especially if it was complicated.