Many systemic diseases, such as diabetes and high blood pressure, can cause retina damage and lead to vision loss.
Many systemic diseases, such as diabetes and high blood pressure, can cause retina damage and lead to vision loss.
AMD main symptoms are central vision weakening, distorted vision (straight lines seem wavy) and less vividness of color.
Scientists are still researching what causes AMD, but the current recommendation include:
1. Eat small amounts of fat and large amounts of vegetables and green leaves, as spinach, collard greens, broccoli, and arugula;
2. Protect your eyes against UV rays wearing clear or sunglasses with UV protection;
3. Do physical exercises regularly;
4. Do not smoke.
There are special situations when other treatment might be used, such as photodynamic therapy (PDT) and laser photocoagulation. Other alternative treatments are in research and development and we will probably have them available in the market in the near future.
The retina is a fine membrane which lines the inside of the eye. Every light stimulus that reaches the inside of the eye is captured by the retina and transformed into electric pulses. These pulses are sent to the brain, where the image is formed.
Retinal detachment is the retina separation from its area of adherence inside of the eye. Such retinal area does not capture light anymore and, consequently, the electric stimulus is not sent to the brain, resulting in vision loss.
The most important symptom is sudden central and/or peripheral vision loss with the sudden perception of a dark curtain, which progressively gets worse. Usually, days or weeks earlier, the patient notices floaters, similar to mosquitoes or spider web, and sudden flashes of light, like a lightning, as there is movement of the head or eyes (photopsia).
If a person suddenly has these symptoms, an eye exam must be done urgently, since it can be the start of a retinal rupture, which precedes a detachment. Early diagnostic allows the retinal detachment preventive treatment by laser application.
The most common causes of retinal detachment are age-related vitreous detachment (vitreous is the gel that lines the inside of the eye), nearsightedness (myopia), ocular trauma, ocular inflammation, diabetes mellitus and intraocular tumor (mass).
Surgery is the treatment for retinal detachment. The procedure will depend on the type of detachment, the number of retinal ruptures (holes or tears), and some other factors.
Usually, treatment is done by emptying the fluid that induces further detachment, followed by laser cauterization at the place of rupture, and insertion of a silicone prosthesis behind the eye, over the white layer (sclera), to promote greater adherence between the retina and the tissue that keeps it in place.
In more serious cases, the vitreous humor is removed (vitrectomy), followed by laser application and insertion of special gases or silicone oil into the eye.
Surgery for Retinal Detachment
Epiretinal membrane (ERM) is a thin layer that lines the retina surface. It is associated with diseases in the eye fundus, such as inflammations, infections, blood vessel alterations, etc. However, most patients have no predisposing factor and the epiretinal membrane appears because of age-related alterations in the eye (idiophatic ERM).
Usually idiophatic ERM appears after 50 years of age. Most cases have no visual symptoms. Sometimes the patients relate vision weakening or distortion, and occasionally double vision.
During the fundus exam the membrane appears as a thin irregular reflection layer in the macula (central area of the retina), with wrinkles and striae (stretch marks) on the retina, and also blood vessels dilated and crooked.
The most important additional exam to confirm ERM diagnosis is OCT – Optical Coherence Tomography. It allows the detailed evaluation of the fovea contour (fovea is the macula’s central point), and the thickness and volume of the macula. It is of great help during a pre-op evaluation and in long term follow-ups.
When there is a need for treatment, surgery is performed. The vitreous humor and the ERM are removed. Vitreous is the gel that lines the inside of the eye. Special dyes, such as Trypan blue or sparkling blue, can help the surgeon to see and remove the membrane.
Retinal thickness diminishes gradually after ERM removal. Most patients have partial visual improvement.
Laser treatment on the retina, known as photocoagulation (Figure A – Retina before the laser. Figure B – Retina after the laser), is the main treatment for diabetic retinopathy. It allows disease control, most of the time, avoiding evolution and grave vision loss. Laser photocoagulation is performed in one or more sessions, making several micro burns on the retina to cauterize permeable blood vessels and avoid the growth of new vessels. This procedure can be done with the use of anesthetic eye drops, what allows the patient to go home without a bandage, right after the laser. In more severe cases, many laser shots might be needed during one session. To avoid pain, in this situation, a local injection of anesthetic is used and a dressing is placed over that eye. The dressing is removed on the following day.
Diabetic retinopathy most severe cases, with large hemorrhage (bleeding) in the vitreous and/or with retinal detachment, need a surgical treatment called vitrectomy. In the vitrectomy the vitreous (and blood) is removed and the retina is repositioned back in place. This procedure brings partial visual recovery to some patients, mainly when there has not been a detachment of the central retina neither a secondary glaucoma.
Intravitreal therapy with antiangiogenics and corticosteroid is a recent procedure that helps to treat specific cases of diabetic retinopathy. The main reason for this therapy is a diabetic macula edema, which is the central retina swelling caused by plasma leakage from the permeable blood vessels. After local anesthetics are applied around the eye, the medicine is injected in the eye. The medicine promotes the reabsorption of the liquid present in the macula often results in visual improvement.
It is essential to explain to the patient what to expect of his vision after the treatment. Depending on the disease’s stage it might be possible to have visual improvement. Sometimes the vision remains the same but it is possible to avoid the disease’s progression, which would lead to permanent blindness.
Intravitreal Injection – surgical video:
Surgery for Diabetic Retinopathy – surgical video:
It is a retinal tumor. The retina is the membrane sensative to light located in the eye fundus. It is the most common eye tumor in childhood and 10% are hereditary. Children of both genders and any race might get it. Retinoblastoma affects one or both eyes and is very aggressive. It can even be fatal if it invades the brain. Sometimes the tumor is associated with changes in other parts of the body.
The tumor can be present at birth but usually affects children two and half years old or younger. This is the reason parents and pediatricians must be alert to any sign in the child’s eyes. When the tumor is detected early, the vision and the child’s life can be saved.
Retinoblastoma’s main sign is a whitish sparkle in the pupil of the child (cat eye reflex), noticed better under artificial lighting. Other alterations which are easier for the parents to notice are vision impairment and strabismus (crossed eyes).
Flash photographies can raise suspicions of the disease when the reflex of the pupil of one or both eyes is not redish. However, an absence of the redish reflex is not always caused by retinoblastoma. Other causes might be cataract, glaucoma and infections inside of the eye.
The red reflex test (also called red eye reflex test) performed by the peciatrician a few days after birth is one of the exams able to detect a tumor early on. However, the parents also have an important role to report any alteration in the child’s eyes since the retinoblastoma might appear later in life.
If there is a suspicion of retinoblastoma, an eye exam, an ultrasound and a computerized tomography of the eyes will always be performed. These exams help to diagnose and treat the disease.
Treatment varies depending to the tumor’s size and changes in other parts of the body.
1. Small tumors are treated with laser (photocoagulation).
2. Medium size tumors will need chemotherapy (medicine injected into the veins), radiotherapy (radiation delivered near the eye) and photocoagulation.
3. Large tumors will require the removal of the eye (enucleation), usually combined with chemotherapy and radiotherapy.
If the eye has to be removed it might be possible to replace it with a prosthesis. The doctor will explain this during the eye exam. Modern prostheses are very sophisticated to improve the appearance of the patient, but they do not restore vision.
It is the uveitis caused by the Toxoplasma gondii, a parasite. It is the most common uveitis in Brazil. Toxoplamosis final hosts are cats and other felines. Man gets the disease when:
– Cysts are eaten. Cyst might be in raw or rare meat, especially pork and lamb.
– Ingested cysts from cats, and in water, soil, raw or improperly cleaned salads and vegetables. It is more common in children and people who work the land.
– Transmitted through the placenta: the fetus acquires the disease when the mother gets it during the pregnancy.
– Inoculation of the agent through blood transfusion, organ transplant and laboratory accidents.
Generally toxoplasmosis is found in newborn babies, teenagers and young adults. It causes localized inflammation of the retina and choroid, with varying degrees of blurred vision from person to person.
One person can have more than one outbreak of the disease. Thus far there is no vaccine or treatment to avoid a new outbreak on those patients at greater risk.
Toxoplasmosis is treated with medicine, to kill the infectious agent (the parasite) and resolve the eye inflammation.
Toxoplasmosis prevention is essential: avoid eating raw or rare meat, thoroughly wash hands and food, drink treated water, and avoid contact with a cat`s private parts and feces. Pregnant women must undergo lab exams to verify if they have toxoplasmosis antibodies.
It is the uveitis caused by the Toxocara canis or Toxocara cati larvae. It mainly affects children that play at places where there are dogs and cats. It causes eye inflammation and a small nodule in the eye fundus, at the central retina (Figure 4) or the peripheral area. Treatment`s goal is to decrease the inflammation inside of the eye. Prevention comes by not letting children play in possibly infected places, such as sand boxes where dogs and cats might have defecated and released the toxocariasis larvae.
It is the infection caused by a larva that moves around inside of the eye, underneath the retina (Figure 5). It is more common in children and young adults. It causes progressive vision weakening in one of the eyes, and it might go unnoticed. If discovered early, it might be possible to maintain good vision, however, in later stages, the disease leads to irreversible loss of central and peripheral vision. The main treatment is photocoagulation, which is a laser procedure to kill the larvae. This treatment will inactivate the disease permanently..
The rubella virus can cause changes in fetuses of pregnant women that acquire the infection during the first gestational trimester. The main consequences are cataracts (Figure 7), microphthalmia (eye abnormally small), deafness, microcephaly (brain abnormally small), mental retardation, and changes in the heart. The “salt and pepper” chorioretinitis is one of the most common changes. It got this name because areas of the retina have little or too much pigmentation, with lighter spots (“salt”) and darker ones (“pepper”) (Figure 8). It is not possible to intervene with the eye fundus changes. If a cataract is found right after birth, surgery must take place as soon as possible to allow the best visual development possible.
It is a serious infection in the eye fundus caused by herpes zoster or herpes simplex virus.
It causes visual weakening in one or both eyes, differently from one person to another. Usually it progresses until it affects the central and peripheral vision (Figure 9 A/B). Even when not treated, the eye inflammation will disappear between 6 and 12 weeks. The main complication is retinal detachment, which happens in more than 75% of the affected eyes (Figure 10). Emergency treatment with antiviral shots aim to overcome the affected eye infection and inflammation, and to lower the chance that the infection affects the other eye. Sometimes an additional treatment might be prescribed which can be a laser procedure or conventional surgery on the affected eye.
The light rays enter the eye, go through clear structures (cornea, aqueous humor, lens, vitreous humor) and are captured by the retina, where specialized cells (photoreceptors) transform the luminous stimuli into an image. The image is sent through the optic nerve to the brain, where it is processed.
The area of the retina able to generate the best quality image is called the macula.
A macular hole occurs when there is a loss of tissue in the central retina area. This can happen as a consequence of eye trauma or eye inflammation. However, a macular hole is more often caused by age related changes, without previous eye disease. In this case, it is known as a primary macular hole.
When the macular hole is established, it tends to increase in size over time, and central vision worsens as a result. It is unusual, even rare, for the macular hole to heal and close by itself.
A patient with a macular hole has central vision difficulties and image distortion. Optical Coherence Tomography (OCT) is an essential exam to confirm that there is a macular hole and to evaluate its size and characteristics.
The main retinal distrophies are retinitis pigmentosa, Stargardt disease, Best disease (vitelliform macular degeneration), and cone dystrophy.
The retinitis pigmentosa can be hereditarily transmitted in many ways and affect several people of the same family. Sometimes, the disease affects only one person within a family.
Diagnosis is achieved by means of a complete eye exam with pupil dilation. The exam that evaluates the fundus of the eye (fundoscopy) allows the analysis of typical signs of the disease. A campimetry (measurement of the visual field) might be requested and, many times, an angiofluoresceinography (retina exam using fluorescein dye) and an electroretinography (evaluation of the electrical patterns of the retina).
There is no effective treatment for retinitis pigmentosa yet. Many ideas are under research and development, such as gene therapy for Usher syndrome (a type of retinitis pigmentosa associated with deafness).
The diagnosis can be confirmed through angiofluoresceinography, campimetry, and electroretinography.
To confirm the diagnosis the following exams might be used: Optical Coherence Tomography (OCT), angiofluoresceinography, and electrooculography (exam of the electrical patterns of the deeper layers of the retina).
The diagnosis is achieved with the aid of the following exams: fundoscopy associated with color vision test, angiofluoresceinography, campimetry, and electroretinography.
Customer Service WhatsApp (Mon to Fri)
from 08:00 a.m. to 6:00 p.m. +55 47 99647-3800
Veralúcia Ferreira Oliveira, MD Technical Responsible - Ophthalmologist CRM-SC 4160/ RQE 1972