They include flashes, sparks or flashing light that usually occur on the periphery of the visual field. These light perceptions (as if “seeing sparks”) may also occur as a result of vitreous commotion after striking the eye or after a strong hit to the head. Should they occur without an external cause, they can be the first sign of retina damage.
The retina is a thin layer at the back of the eye whose main function is to detect light signals as the light comes through the lens and hits the retina. Retinal diseases may have various causes, including for example hereditary causes or vascular diseases (artery and venous closures or vessel anomalies). The most vulnerable group are patients suffering from diabetes. In these patients, damage to the retina is called diabetic retinopathy. However, retinal inflammations may also be the cause of retina damage. All these may lead to breaks in the retina and finally to retinal detachment. If not treated, it may lead to permanent blindness.
For better visualization, you will be administered special drugs in the form of drops to dilate your pupil (artificial mydriasis). Shortly after the exam (a maximum of a few hours), you might experience worsening of your vision or higher light sensitivity due to the previous pupil dilatation. Therefore, we strongly recommend no driving immediately after the examination. However, the above mentioned symptoms will wear off when the drug effects disappear.
You will also be examined by an ophthalmoscopy – directly or indirectly. In both cases, it is an exam that will not cause you any difficulties or discomfort. The direct ophthalmoscope is a device that is held in the doctor’s hand. Using a special light installed inside the ophthalmoscope, the doctor will look into your eyes. As far as indirect ophthalmoscopy is concerned, the doctor will wear a special binocular device with a light inside when examining your eyes. There is also a special form of indirect ophthalmological exam called a biomicroscopy. This technique is used to examine the eye background, known as the retina. It is also a pain-free procedure done with a slit lamp. In this case, the doctor holds an ophthalmoscopic lens in front of your eye.
Another modern imaging method is optical coherence tomography (OCT), which enables imaging of cross sections of the retina, thickness of retina swelling, and the type and depth of the damage. This method is done using a special device and you will be asked to sit in front of it.
If a patient is suffering from retinal diseases, most commonly vascular ones such as diabetic retinopathy, the doctor can prescribe some tables to strengthen the vessels – venopharmacs. These substances protect vessel walls, help to improve their functions, and they have anti-inflammatory and anti-edematous effects as well. They can also reduce formation of blood clots or help in their dissolution. These drugs are made of either natural substances, (flower flavonoids e.g. rutin), or polysynthetic, or synthetic ones (e.g. calcium dobesilate).
To prevent retinal or vitreous body bleeding or for their treatment, hemostatics are recommended. These can be administered in tablet or injection form.
The doctor may also recommend using food supplements that contain antioxidants such as lutein and zeaxantine. They are naturally present in yellow spot pigment. They absorb UV radiation and protect cells against oxidation changes. The human organism is not able to produce these substances as it increases in age, and so it is recommended to get them from food as a means of preventive care.
Pars plana vitrectomy
Pars plana vitrectomy is a surgical procedure in which vitreous body or membrane opacification is cured together with bleeding into the vitreous body. It is done under local anesthesia while a doctor observes the whole procedure under a microscope. The devices are inserted into the eye through the ciliary body, a circular structure at the front of the eye serving to maintain the proper position of the lens and for accommodation. Then the diseased vitreous body is removed and replaced by an infusion of a salty solution.
Two surgical procedures are used: stitch and non-stitch vitrectomy. The former includes a cut of 0.9–1 mm in the ciliary body area by using a special knife. The diseased vitreous body is cut off and sucked out. It lasts about 30 – 60 minutes. The wound is finally sewed up with self-dissolving sutures.Finally, the vitreous cavity is filled with a physiological solution such as expansive gas or silicone oil. These substances inhibit natural retina healing in the postoperative period. If gas or oil is applied, we call it an inner tamponade. The gas is absorbed after some time and it is replaced by liquid produced in the inner eye. The oil, on the other hand, cannot be absorbed and stays in the eye for several months. Therefore, it has to be removed by means of an operation and replaced by liquid later on.
Surgery is done on an outpatient basis. The pain is suppressed by analgesics. Irritation and eye reddening fade away in the days following the operation. Follow the doctor’s advice and apply into your eyes prescribed drops or ointments.
In treating the development of non-complicated retinal detachment, the doctor can choose episclerar plombage. This procedure involves filling the retinal break that is causing the detachment. It is performed through external access. Firstly, the doctor removes the conjunctiva (the membrane extending from the inner eyelid to the sclera and finally to the cornea) and uncovers the sclera (the white external part of the eye). He will then search for a place with a tear underneath. The eye wall in that place is then frozen and stitched up by a silicone filling. The silicone filling stays under the conjunctiva and if its eruption to the surface does not occur, it is not necessary to remove it afterwards.
It is an effective surgery in which detachment of the retina is corrected. A special gas is fused into the eye and the pressure causes re-attachment of the retina.
Diabetic retinopathy can be treated effectively by using a type of laser surgery based on the photocoagulation principle (photos = light, coagulation = blood clotting). Using a slit lamp and a special lens the doctor focuses a laser beam into the eye and aims at the eye periphery (retinal edges). He has to avoid the retinal center, as it is the sharpest point of vision, as well as avoiding the eye nerve exit and vessel supply entry. Therefore, it is necessary to protect these areas against any damage. In the pigment cells, a laser beam transforms into heat that creates a blood clot at the location of the damage. The blood clot obstructs the vessel, which dies out due to lack of oxygen. The avascular retinal part is then removed because it stops producing the growth factor that leads to the formation of new vessel production. Therefore the cause of the diabetic retinopathy is, in ideal cases, completely removed.
Laser retina treatment is done on an outpatient basis. Firstly, the pupils are dilated. The surgical procedure might be slightly uncomfortable but nonetheless it is pain-free, lasting around 10 – 30 minutes. Vision acuity is worsened several hours afterwards so it is not possible to drive after the operation. However, other physical activities are not limited.
Inner eye AVASTIN injection
A drug by the trade name Avastin (chemo-drug bevacizumab) was originally used in the treatment of tumors because it can bind tightly to VEGF protein (VEGF = vascular endothelial growth factor). Avastin functions to encourage blood vessel growth. However, if Avastin binds to the VEGF protein, its activity is blocked, interrupting new vessel growth. In ophthalmology, Avastin has been successfully used in the treatment of a damp form of senile macular degeneration and retinal swelling occurring as a result of inflammation or diabetic retinopathy. Before the doctor applies Avastin, the patient’s eye is anesthetized by anesthetic drops. Then about 0.1 ml of Avastin is injected into the vitreous body using a very thin needle. This procedure is repeated usually three times over a series of months.
Inner eye injection of Triamcinolon
Triamcinolon is an artificial hormone that has prominent antibacterial and anti-allergic effects. It is used in ophthalmology to treat macular edema, chronic inflammatory diseases, allergies or increased body stamina reactivity. Firstly, the doctor anesthetizes the eye with drops, then injects with a very thin needle 4 mg of Triamcinolon into the vitreous body.
It is used mainly in treating the retina in patients suffering from diabetic retinopathy. While applying laser beams through a special lens, light radiation (532 nanometer waves) is absorbed mainly by the retinal pigment cells and transforms into heat, thus causing destruction of the target cells and surrounding tissue. Scars are formed in the insufficiently supplied vitreous areas and the blood supply is transited into the area of the sharpest vision, which is left untouched by the laser. We use the Alcon Company device in our clinic.
A device used for operating on the posterior segment of the eye. It is a high-frequency mini-knife that serves for removal of the vitreous body and other damaged tissue. It is not necessary to sew up the wound afterwards. Vitrectom is operated by a PC, which provides the maximum amount of safety throughout the procedure.
Inner eye AVASTIN injection
Avastin is a healing substance used to block new vessel growth in the diseased retina and to decrease/stop substance infiltration into the retinal vessels. It reduces the spread of disease (diabetic retinopathy, retinal swelling etc.) and leads to vision improvement. After the eye is anesthetized by drops, an injection is painlessly applied using a very thin needle (0.3 mm in diameter) and a small amount of healing substance is administered (0.1 ml.).