The symptoms of retinal detachment include the disappearance or blurring of the sight. It can be a part of the vision or the eye as a whole.
Retinal detachment means the separation of photosensitive nervous tissue, which allows the eye to perceive images and colors from the posterior wall of the eye. Retinal detachment is a very serious case for the eye and sight. The more critical the disease, the more extended is the detached part.
Pathogenesis of Retinal Detachment
It is necessary to imagine the inner part of the eye as a swimming pool and the retina as the blue carpet that covers it completely. But, inside the pool instead of water there is a sort of sticky gel.
The gel (the vitreous body of the eye) is tenaciously attached only to the edge of the pool, while it is weakly attached to the rest of the blue carpet. Over the years, the vitreous gel undergoes a progressive degeneration that leads it to liquefy over time. This is why the so-called flying flies (miodesopsias) that many people perceive. This transformation causes the gel to detach itself from the blue carpet (the retina), remaining attached only to the edge.
This is a physiological event, which basically happens to anyone at old age. However, in some cases, the sticky gel detachment from the back of the retina is not complete, but a small part of it remains tightly attached to the blue carpet (retina), usually near the edge, but distinctly from it.
Imagine the movements of the head and body like an earthquake that hits the pool. The gel violently sets in motion by the earthquake and strongly attaches to one point of the carpet as well as on the edge. This inevitably produces tractions on the point itself which can ultimately disrupt with the formation of a break. At this point, the water inside the pool can creep behind the carpet and detach itself more or less extensively.
The vision is compromised and may get blurry or lost. When even the central part of the visual field is blurred, it means that the detachment has involved the macula, the noblest part of the retina. In these cases, the prognosis is more serious and the chances of visual recovery after surgery are less.
Sometimes, a retinal detachment is preceded by the sudden appearance of flashes of light (photopsia). Also, with the spies of traction by the vitreous body on the retina, forming a retinal rupture.
In most cases, the retinal detachment is caused by a retinal rupture, a consequence of the posterior detachment of the vitreous. High myopia, cataract extraction surgery, and trauma increase the risk of retinal detachment.
In the case of retinal detachment or the appearance of the symptoms listed above, it is essential to go immediately to the ophthalmologist. The doctor, with an examination of the fundus of the eye, can realize the situation and implement the most appropriate recovery strategies.
The eye is filled in its central part by a transparent gel, the vitreous, closely adhered to the retinal surface. Over the years, the vitreous normally undergoes progressive liquefaction and eventually loses contact with the retina. Usually, when the vitreous is detached from the retina it does not cause any disturbance. Occasionally, the appearance of the so-called flying flies or vitreous moving bodies may occur. Sometimes while detaching, the vitreous pulls on the retina enough to form a rupture in one or more points. In that case, the fluid inside the eye can creep behind the break and lift the retina from the back wall of the eye, as if the wallpaper was detached from a wall.
The treatment of retinal detachment is surgical and is based on the release of vitreous traction (gel) on the retina and in the closure of the rupture causing detachment.
There are two types of intervention: the traditional method with vitrectomy. The traditional intervention consists of placing a “belt with stud” on the outside of the eye so that the outer wall of the eye is brought closer to the detached retina. As a result, makes the vitreous gel to release the traction on the break itself.
The breakage no longer subjected to traction, can then close. Then the laser or the cryo (cold treatment) is made around it to prevent it from reopening. The advantage of this technique is the lower incidence of infectious and cataract complications. However, not all types of retinal detachments can be treated in this way.
The vitrectomy is instead a more modern operation, performed directly inside the eye. It activates three tiny little holes in the outer wall, for the insertion of as many instruments. With the aid of an instrument: the vitrectomy that cuts and sucks, the vitreous gel is almost completely removed, eliminating the cause of the break that can no longer be subjected to traction and can, therefore, be closed and sealed even in the case of a laser or cryopexy treatment (cold).
Unless the patient has particular conditions or preferences, all interventions for retinal detachment can be performed safely under local anesthesia without the requirement of hospitalization. The patient, once operated, can go home comfortably and return the next day for post-operative checks.
Currently, the results of retinal detachment surgeries are very good. Anatomical success is predicted with only one intervention in about 90% of the cases and with two interventions in more than 95% of the cases. Unfortunately, sometimes more than one intervention is necessary, due to the abnormal healing process that the eye spontaneously sets in motion: vitreoretinal proliferation. Visual recovery after retinal detachment surgery varies and depends fundamentally on the involvement or exclusion of the central part of the retina: the macula.
The prevention of retinal detachment is based exclusively on the education of the patient about the symptoms of it. It also depends on the timely laser treatment (or cryo) of symptomatic retinal breaks (accompanied by flashes and flying flies), which still haven’t have led to detachment. Asymptomatic retinal breaks or peripheral degenerations, discovered during a check-up visit do not require treatment, keeping in mind that retinal detachment has not already occurred in the other eye.
A retinal detachment can be prevented in two ways: with accurate awareness and with the timely treatment of rhegmatogenous retinal lesions. In most cases, a retinal detachment is preceded by the formation of a retinal rupture. Retinal rupture is generally caused by the sudden detachment of the vitreous. Laser treatment is generally very effective in preventing retinal detachment caused by symptomatic rupture.
Hence, the detachment of the vitreous is often preceded by the perception of luminous flashes in the visual field. For this reason, if a sudden flash of light is felt, it is important to go to the ophthalmologist immediately. The doctor will take an examination of the ocular fundus and will be able to diagnose a retinal rupture and possibly treat it in order to avoid a retinal detachment.
However, the presence of luminous flashes does not always necessarily mean a retinal rupture. They can sometimes be perceived in conjunction with an episode of ophthalmic migraine. However, in this case, they are usually perceived bilaterally, i.e. by both eyes simultaneously.
Symptomatic And Non-Symptomatic Rupture
In the process of vitreous detachment, although the perception of lightning is frequent, a break occurs approximately 10% of cases. The asymptomatic retinal rupture that is accompanied by flashes of light, if not treated promptly, involves a high risk of developing a retinal detachment.
On the other hand, a non-symptomatic retinal rupture that is casually found by the ophthalmologist during a routine examination of the ocular fundus presents a low if not zero risks of detachment. The difference between the two forms is to be recognized in the vitreous.
In the first case, the vitreous is attached to the edge of the rupture (pulling it produces luminous symptoms) and keeping it open allows the passage of water below the retina. In the second case, the retina is not subjected to traction by the vitreous and consequently does not risk detaching (and therefore does not produce symptoms).
Symptomatic retinal rupture can occur anywhere in the retina. However, in most cases, ruptures are usually found in the retinal periphery. Particularly at the level of areas with latex retinal degeneration. Latex degenerations are alterations of the retinal tissue characterized by greater adhesion of the vitreous. Therefore, at the time of a vitreous detachment, they are more like to be subjected to traction, with the resulting formation of a break.
Laser photocoagulation is an effective method to prevent a detachment arising from asymptomatic retinal break. The treatment of non-symptomatic lesions is not necessary, except for a retinal detachment that has already occurred in the other eye.
The Laser Procedure
The retinal laser is an outpatient para chirurgical procedure. The laser instrument is usually coupled with a normal slit lamp, the instrument with which the ophthalmologist normally examines patients’ eyes. To focus the laser rays on the retina, a contact lens is placed on the patient’s cornea after using a drop of anesthetic.
A contact lens rests on the patient’s cornea to focus the laser beam on the retinal periphery, where the rupture is located. Thanks to the slit lamp and the contact lens, the ophthalmologist detects breakage on the retinal tissue. Finally, the laser creates spots around the break, coagulating the surrounding retinal tissue, thus joining it to the ocular wall.
The treatment is called barrage in order to indicate a barrier of the break. Hence, being able to prevent the spread of a possible detachment. At the end of the intervention, the patient can immediately go home. However, it takes a few days before the laser reaches maximum effectiveness, and therefore a short rest period is indicated.
Prognosis and Risks
The retinal detachment treatment which involves laser procedures is generally very effective in preventing retinal detachment caused by symptomatic rupture. Sometimes it is even possible to block minor retinal detachments.
The risks of the procedure are few or none if the laser is correctly used. However, after a while membranes can form on the retinal surface. Even if it is at a distance from the laser site, as in the case of the macular pucker. This occurrence is more frequent in the case of heavy treatments. However, if the view is disturbed, it may entail the need to perform a surgical operation to remove the membranes.