Retinal Surgery in Turkey

Retinal surgery, known in medical literature as vitreoretinal surgery, is a highly delicate microsurgical procedure performed to repair damage to the nerve layer lining the back wall of the eye and responsible for vision. In conditions carrying a risk of permanent vision loss, the internal cavity of the eye is treated with the help of special microscopic instruments in order to restore the disrupted anatomical structure. This advanced technology treatment approach, which aims to preserve the quality of vision and safeguard eye health, enables the tissues at the back of the eye to regain their functions. This meticulous repair process, carried out to restore the healthy functioning of the tissues, directly determines patients’ visual quality of life.

What is retinal surgery?

To better understand how our visual system works, we can compare the eye to a camera. The transparent corneal layer at the very front of the eye and our natural lens located just behind it function as the lens of this camera and focus incoming light. The retinal layer, which lines the inner wall of the eyeball almost like wallpaper, is the film of the camera. Consisting of millions of specialized nerve cells that detect light, the retina converts this visual information into electrical signals and transmits them to the brain through the optic nerve. In order for the retina to maintain this vital function, it is expected to remain firmly attached to the vascular layer beneath it from which it receives nourishment.

The structure that fills the central cavity of the eye and helps maintain its spherical shape is called the vitreous. During our younger years, the vitreous is a fairly dense and transparent gel with a consistency similar to egg white. However, as we age, if we have high degrees of myopia, or as a result of various impacts to the eye, the structure of this gel gradually deteriorates and begins to liquefy. As the liquefied gel contracts, it attempts to separate from the retinal layer with which it is in contact. This separation process may not always occur normally. If the gel pulls excessively on the retina at certain weak points, tears may occur in the retinal tissue. These anatomical disruptions in the internal dynamics of the eye are among the main processes that make surgical intervention necessary.

Which eye diseases and symptoms may indicate the need for retinal surgery?

Various diseases that develop in the back of the eye directly threaten visual function. Retinal detachment is one of the foremost of these. Intraocular fluid leaking through a tear in the retina causes the retina to separate from the layer that nourishes it and become elevated. This condition, which develops much like wallpaper peeling away after absorbing water, requires urgent surgical repair. If treatment is delayed, the nerve cells deprived of nourishment become damaged and vision loss may become permanent.

Diabetic retinopathy caused by diabetes is also an important surgical indication. Diabetes that persists for many years and is not sufficiently controlled damages the structure of the fine capillaries inside the eye. This causes oxygen-deprived tissues to produce new but extremely fragile blood vessels. These abnormal vessels can bleed easily and fill the eye cavity with blood or form contracting membranes that pull the retina away from its position. In addition, holes that develop in the macula (yellow spot), which is responsible for sharp central vision, or thin membranes that wrinkle this area (epiretinal membranes) are other common conditions repaired surgically.

The warning signs most commonly encountered by patients during this process are as follows:

• Flashes of light
• Black spots
• Floaters
• Soot-like specks
• Cobweb-like images
• Narrowing of the visual field
• A sensation of a curtain descending

Which examinations are performed on our patients before a decision for retinal surgery is made?

The fundamental key to surgical success is mapping the back of the eye in great detail before intervention. For this purpose, the pupils are first dilated with special drops. Physicians perform a comprehensive fundus examination extending to the outermost areas of the retina using biomicroscopic lenses. During this examination, the aim is not to overlook even the smallest tear or weak area.

In diseases involving the macula, which is the center of vision, an advanced imaging method called Optical Coherence Tomography (OCT) is used. This method, which does not involve radiation and works with light waves, displays the microscopic layers of the retina in cross-sectional images. In this way, the diameter of holes, the thickness of membranes, and fluid accumulations can be measured with a precision of one-thousandth of a millimeter. If there is dense bleeding inside the eye and the back of the eye cannot be visualized with light, ocular ultrasonography, which works with sound waves, is used. Ultrasonography helps determine the surgical strategy by mapping the condition of the retina and tractional bands behind the bleeding.

How is vitrectomy, the most commonly performed retinal surgery method today, carried out?

Pars plana vitrectomy is the most frequently used closed-system surgical technique in modern eye surgery. The main purpose of the procedure is to remove the deteriorated vitreous gel and tissues obstructing vision from inside the eye using very fine microsurgical instruments. In modern applications, the inside of the eye is accessed through entry sites that do not require sutures and are only fractions of a millimeter in diameter (23, 25, or 27 gauge). Usually, three thin tubes are inserted through the white part of the eye. One of these tubes continuously delivers fluid to prevent the eye from collapsing, another serves as a fiber-optic light source illuminating the dark interior of the eye, and through the third tube, instruments capable of making thousands of cuts per minute while simultaneously vacuuming and removing tissue are advanced.

During the operation, special tissue dyes may sometimes be used to make the transparent gel more visible, and the gel is carefully removed. If the retina has detached, special substances called heavy liquids are introduced into the eye to gently flatten the retina back onto its original bed while the fluid underneath is removed. In macular holes, a very thin membrane on the uppermost surface of the retina is carefully peeled using microscopic forceps. Once the retina is repositioned, laser shots are applied from inside the eye around the tear so that the tissues adhere to each other and prevent further fluid leakage. At the end of the procedure, the fine entry sites usually close on their own and sutures may not be required.

In which situations is the retinal surgery technique called scleral buckling preferred?

Unlike vitrectomy, another treatment option performed entirely from the outside without entering the eye is scleral buckling surgery. In this method, rather than removing the tractional gel from inside the eye, the aim is to indent the outer wall of the eye inward and thereby reduce tension in the area of the retinal tear. During the procedure, flexible silicone bands or sponges are secured to the sclera, the white layer of the eye, using special sutures. These bands gently compress the eyeball from the outside and create an indentation on the inner surface. When this indentation is positioned directly beneath the tear, the pulling force of the vitreous is neutralized and the retina returns to its original position.

To permanently seal the tear area, an external freezing procedure (cryotherapy) may be applied, and fluid accumulated beneath the retina is drained through a small opening. The greatest advantage of the scleral buckling method is that it does not interfere excessively with the internal balance of the eye. In this way, the risk of infection is lower and the development of cataract in the patient’s own natural lens is not triggered. It is considered a highly successful option particularly in younger patients whose vitreous has not completely liquefied and in tears located in the lower parts of the eye.

Is pneumatic retinopexy, known as gas treatment, an alternative to retinal surgery?

Pneumatic retinopexy is a treatment method that may be offered as a less invasive option in certain suitable cases. This tissue-preserving procedure, performed in an operating room setting, may generally be preferred for single tears located only in the upper half of the eye that have not become complicated. During the procedure, a special gas bubble is injected into the eye.

The logic of this procedure is based on the principle that an air bubble in water always moves upward. When the patient positions the head as instructed by the physician, the gas bubble rises and seals the opening of the tear from inside the eye like a plug. Once fluid passage is stopped, the eye’s own physiological pumps absorb the fluid remaining beneath the retina and reattach the tissue to its bed. After the tissue is repositioned, laser treatment is applied around it to achieve permanent adhesion. Its ineffectiveness for tears in the lower part of the eye because of gravity and the need for the patient to comply with a very strict positioning rule are limiting features of this method.

How is the retinal surgery process planned in patients who also have cataracts?

Closed-system vitrectomy procedures, especially in patients above a certain age, may accelerate the development of cataracts some time after surgery because they alter the nutritional and oxygenation dynamics inside the eye. If the patient already has a cataract before surgery or belongs to an older age group with a high likelihood of developing cataracts, physicians generally plan to combine both surgeries in the same session. This combined surgery is called combined phacovitrectomy.

Removing the cataract and repairing the retina in the same session protects the patient from undergoing a second surgery in the future. This combined procedure also provides a major advantage for the surgeon. Removing the clouded lens and replacing it with a clear artificial lens enables the back of the eye to be viewed much more clearly and brightly during the operation. Under this clear view, delicate millimetric cleaning procedures in the peripheral areas of the retina can be performed in a much more controlled manner.

What are the functions of the supporting substances placed inside the eye during retinal surgery?

After the eye’s natural gel is removed during vitrectomy surgery, supporting substances are needed at the end of the procedure to fill the eye and keep the retina in place during the healing process. In medicine, these substances are called intraocular tamponades. It takes time for areas treated with laser or freezing to heal completely and adhere. During this period, tamponades that support the retina from the inside like a bandage play a major role in the success of the surgery.

The main tamponade substances frequently used in these surgeries are as follows:

• Sterile air
• Sulfur hexafluoride
• Perfluoropropane
• Silicone oil

Sterile air is the substance that remains in the eye for the shortest period and is generally preferred in mild cases; it is absorbed by the body within a few days. The medical gases sulfur hexafluoride and perfluoropropane provide longer-term support. The most important characteristic of these gases is that after being introduced into the eye, they expand, increase in volume, and create a broad surface area. While the effect of the first gas ends within a few weeks, the other may remain in the eye for months, and when they complete their function, they are spontaneously absorbed and replaced by the eye’s natural fluid. In much more complex cases, giant tears, or situations in which the patient cannot maintain positioning, silicone oil is used. Silicone does not expand or become absorbed and provides permanent support. However, once its function is complete, it generally needs to be removed from the eye with a second operation after several months. If removal is delayed, it may separate into small droplets and increase the risk of elevated intraocular pressure.

Do patients feel pain during retinal surgery and which types of anesthesia are used?

In eye surgery, it is a major safety factor not only for the patient to feel no pain but also for the eyeball, which is the surgical field, to remain completely motionless under the microscope. In modern retinal surgery, this comfort is mostly provided with local anesthesia methods. In the sub-Tenon anesthesia technique, which is frequently preferred today, a needle is not blindly inserted behind the eye. Instead, an anesthetic solution is administered using blunt cannulas that do not damage tissue and are introduced just beneath the membrane on the outer surface of the eye. This medication spreads through the tissue spaces, eliminates the sensation of pain, and temporarily paralyzes the eye muscles to ensure immobility.

General anesthesia may be preferred in pediatric patients, individuals with very high anxiety about surgery, or cases expected to last a long time. However, there is a very important detail regarding the use of general anesthesia in retinal surgery. If a supportive gas has been placed inside the eye during the operation or if gas from a previous surgery is still present in the patient’s eye, it is vital that nitrous oxide, also known as laughing gas, not be used in the anesthesia protocol. Nitrous oxide rapidly dissolves in the blood, enters the gas bubble in the eye, and suddenly enlarges it within seconds. Because this excessive increase in volume can raise intraocular pressure to dangerous levels, close the blood vessels of the eye, and cause permanent visual damage, the anesthesiologist is always warned about this issue.

Why are the required lying positions important after retinal surgery?

The ability of gas or silicone oil placed inside the eye after surgery to perform its function is directly related to the patient’s lying position at home. These substances are lighter than the eye’s natural fluid and, just like an air bubble in water, tend to float toward the highest point. The patient’s task is to position the head at the angle instructed by the physician so that this rising bubble is located directly over the repaired tear or hole.

The main positions that may be requested from patients according to the location of the operated area are as follows:

• Face-down position
• Right-side lying position
• Left-side lying position
• Semi-sitting position
• Head-down position

For example, if the repaired area is the macular region at the back center of the eye, the patient generally needs to remain face-down, looking toward the floor, for several days so that the bubble can apply pressure to that area. If the tears are located on the sides, the patient is instructed to lie on the corresponding side. If the patient does not follow this positioning discipline and lies on the back, the gas bubble moves forward, leaving the tear at the back uncovered, and fluid may re-enter the tissue space and cause the detachment process to recur.

What are the travel restrictions for patients who have gas in the eye after retinal surgery?

Patients who have had expandable medical gas injected into the eye must pay close attention to flight and altitude restrictions until the gas has been completely absorbed by the body. During air travel, the air pressure inside the cabin decreases significantly compared with sea level. According to the laws of physics, this reduction in external pressure causes the enclosed gas bubble inside the eye to suddenly expand and increase in volume.

Because the eyeball is a closed structure that cannot expand outward, this internal expansion causes a sudden and dramatic rise in intraocular pressure. This crisis can compress the main optic nerve and the arteries supplying the eye, potentially stopping oxygen flow. In addition to air travel, traveling by vehicle through high-altitude mountain passes or road journeys involving rapid changes in elevation carry a similar risk. Patients should avoid high-altitude environments until the absorption process, which may take several weeks depending on the type of gas, has been completed.

How should eye care be performed during the recovery period after retinal surgery?

During the first few days after surgery, patients may notice widespread redness and bloodshot areas in the white part of the eye. This appearance results from rupture of fine superficial vessels at the entry sites and is a natural part of the healing process; it gradually disappears as it is absorbed by the body. During the recovery period, the main goal is to support tissue repair and protect the eye from external infections. Prescribed antibiotic and tissue-healing drops should be administered at the specified frequency while observing hygiene rules.

The main situations that patients should avoid in the early postoperative period are as follows:

• Rubbing the eye
• Contact with tap water
• Heavy physical exercise
• Dusty environments
• Eye makeup

Especially during the first weeks, it is recommended to avoid getting water into the eye while showering and to wash the head carefully by tilting it backward. Possible fluctuations in intraocular pressure are monitored by the physician during regular follow-up visits, and additional pressure-lowering drops may be added to the treatment if considered necessary.

On which factors does visual quality depend after surgical retinal surgery?

With the opportunities provided by modern imaging systems and advanced technological instruments, the goal of restoring anatomical integrity in retinal surgery can be achieved to a large extent. Successful results are obtained in most cases in closing retinal tears and settling the tissue back onto its bed. Macular holes can also be closed to a significant extent through membrane peeling procedures.

However, anatomically correcting the eye does not always mean that previous visual acuity will return. The most important factor determining the functional visual success that will be achieved after surgery is how long the visual center remained detached and deprived of oxygen before intervention. The sensitive cells that detect light are highly vulnerable to loss of nourishment. Therefore, seeking specialist care as soon as possible after symptoms begin and being directed to the correct treatment is the most important measure that can be taken to minimize tissue damage and support visual recovery.