This is a swelling of the central zone of the retina, which is called a yellow spot or macula.
Macular edema – an independent disease or symptom?
Macular edema is edema of the central zone of the retina, called the macula or macula. It is this area of the retina that is responsible for central vision.
Macular edema is not an independent disease, but a symptom observed in some eye diseases: diabetic retinopathy, retinal vein thrombosis, uveitis. Macular edema may occur due to eye injury or after surgery.
How and when does macula swelling occur?
The cause of edema of the macula is the accumulation of fluid in the layers of the macula, visual acuity is reduced. The mechanism of fluid accumulation may be different.
In 1953, SR Irvine first described macular edema that occurred after surgery for the removal of cataracts. To date, this postoperative complication is called Irwin- Gass syndrome. The cause and pathogenesis of this syndrome are still controversial. It is established that the type of surgery affects the frequency of macular edema. For example, after extracapsular cataract extraction, the frequency of its appearance is statistically significantly higher than with intracapsular extraction, and ranges from 2 to 6.7%.
In diabetic retinopathy, retinal edema, including the macula, is associated with impaired capillary network permeability. The fluid sweats through the defective vascular wall and accumulates in the layers of the retina.
With thrombosis of the central vein of the retina or its branches, the permeability of the vascular wall also increases and fluid flows into the perivascular space with the formation of retinal edema.
Often macular edema is observed with vitreoretinal traction – strands between the vitreous body and the retina. Often found in vascular, inflammatory diseases and injuries of the organ of vision. The vitreous body begins to pull the retina behind it, which causes swelling and, with an unfavorable development of the process, a retinal tear.
Clinical manifestations of macular edema
Symptoms of macula edema
- image distortion – straight lines look wavy, curved
- there may be a cyclic decrease in visual acuity at a certain time of day (more often in the morning). Changesrefractionmore oftenarein therange of0, 25
Differences in color perception during the day are very rare.
In uncomplicated cases, for example, after surgery, the macula swelling, as a rule, does not lead to irretrievable loss of vision, but recovery of vision usually occurs slowly: from 2 to 15 months. However, the long-term edema of the macula can cause irreversible changes in the structure of the retina and, as a result, irreversible deterioration of vision.
In diabetes mellitus distinguish focal and diffuse macular edema. Macular edema is considered diffuse if the retinal thickening reaches an area of 2 or more diameters of the optic nerve and extends to the center of the macula and focal – if it does not capture the center of the macula and does not exceed 2 diameters of the disk. It is diffuse edema during prolonged existence that is often accompanied by a significant decrease in visual acuity and can lead to such complications as retinal pigment epithelium degeneration, macular rupture, epiretinal membrane.
During an ophthalmoscopy (examination of the fundus), it is usually possible to establish only pronounced macular edema. If the swelling is not pronounced, it is quite difficult to detect it.
In the initial stage, retinal edema in the central region may be suspected due to dullness of the edematous area. Also, a sign of edema is prominirovanie (bulging) macular area that can be detected by the characteristic curve of macular vessels on fundoscopy under a slit lamp. The foveolar reflex often disappears, which indicates flattening of the central fossa.
There are modern research methods that allow you to identify even minimal changes in the morphology of the retina.
One of the most effective methods for diagnosing macula edema is opt ical coherent tomography. According to this study, it is possible to quantify the thickness of the retina in microns, the volume in cubic millimeters, its structure, and vitreoretinal ratios.
Geydelb ergskaya Retinal tomography can also identify macular edema and quantify retinal thickness (edema index), but HRT cannot provide data on retinal structure evaluation.
Another way to confirm macular edema – Fluorescent H Supply Return retinal angiography – contrast study of retinal vessels. Edema is determined by the area of contrast dispersion without clear boundaries. Using fluorescein angiography of the retina You can determine the source of the sweating fluid.
There are several methods for treating macular edema: conservative, laser and surgical. The management of patients depends on the cause of macular edema and the duration of its existence.
Conservative treatment of macular edema is the use of anti-inflammatory drugs in drops, injections and tablets. Prescribe corticosteroids and nonsteroidal anti-inflammatory drugs (NSAIDs). The main advantage in the appointment of NSAIDs is the absence of undesirable effects arising from the treatment of corticosteroids: increased IOP, decreased local immunity, ulceration of de-epithelized cornea. Preoperative use of NSAIDs increases the effectiveness of cataract surgery. Instillation of NSAIDs should begin a few days before surgery. NSAIDs and corticosteroids are usually used in the postoperative period as anti-inflammatory therapy. Their use can be considered as prevention of postoperative macular edema or treatment of its subclinical forms.
In the absence of the effect of conservative therapy, certain drugs are injected into the vitreous cavity, for example, long-acting corticosteroids or drugs specifically designed for intravitreal administration.
In the presence of marked changes in the vitreous body – traction, epiretinal membranes, produce vitrectomy – removal of the vitreous body.
The only treatment for diabetic macular edema is laser retinal photocoagulation. A fundamentally important condition is the earlier laser treatment. The efficacy of laser coagulation has been proven in focal macular edema. At the same time, according to many researchers, despite the laser treatment of diffuse edema, the prognosis for visual functions is poor.
The essence of laser coagulation of the retina in macular edema is reduced to coagulation of all defective vessels, through the wall of which leakage of fluid occurs. The center of the macula must remain unaffected.
The prognosis for macular edema depends on the pathology against which it originated, on timely diagnosis and early treatment. The most favorable prognosis in cases of postoperative macular edema is that it resolves within a few months and visual functions, as a rule, are fully restored.
The key to successful treatment is timely referral to a specialist. Even if you have been observing an oculist for a long time about any disease and know your diagnosis, you do not need to neglect minor, in your opinion, symptoms. Be attentive to your health!