Durban Retinal AssociatesDurban Retinal Associates

The retina is the nerve layer that is responsible for receiving images and sending them to the brain. It is a very sensitive layer of tissue that lines the back surface of the inside of the eye and is critical for vision. The retina has many different receptor cells (known as the “rods” and “cones”) and has different areas that perform different functions. For example, the cone receptors are grouped together in a small part of the retina called the macula, and their job is to control colour vision, reading and all fine visual tasks. The rod receptors are found in the area more peripheral areas of the retina and these receptors control peripheral vision and vision in the dark.

A retinal detachment occurs when the retina becomes separated from the wall of the eye. If this occurs, the retina starts to lose its function and visual loss occurs.

CAUSES OF RETINAL DETACHMENT

  • Retinal detachmentRhegmatogenous retinal detachment:  this is the most common cause of retinal detachment and results from a small tear in the retina.  Fluid from the inner cavity of the eye moves through the tear and separates the retina from the wall of the eye.
  • Tractional retinal detachment:  this is much less common, but is caused by some scar tissue that forms on the surface which pulls on the surface of the retina, detaching it from the wall of the eye.  The most common cause of this type of detachment is diabetes.
  • Exudative retinal detachment:  in rare cases, fluid develops under the retina from leaky abnormal blood vessels, a tumour or inflammatory tissue under the retina.

 

SYMPTOMS AND RISKS OF RETINAL DETACHMENT

Symptoms

The sudden onset of floaters and flashes in one eye is an important warning sign, which usually indicates that the vitreous fluid is separating from the surface of the retina.  This separation is called a posterior vitreous detachment or PVD and is a normal process.  Unfortunately, however, some people will develop a tear to the retina as a part of the PVD process.  If the tear is undetected it may allow the retina to detach. Wherever the retina detaches, vision is lost and a shadow develops.  This usually starts on one side and extends to involve central vision. There may be a “grey curtain” or  “veil”  across the vision, or dark spots floating about.  Most commonly, the shadow starts near the nose.

Risks

  • Increasing age
  • Short-sightedness (myopia); the risk increases about four-fold to 10-fold
  • Inherited degenerations of the peripheral part of the retina
  • A history of retinal detachment in one eye
  • A family history of retinal detachment and inherited weakness in the retina
  • Previous cataract surgery
  • Trauma

DIAGNOSIS OF RETINAL TEAR OR DETACHMENT

You will need to be examined by your ophthalmologist. This involves:

  • A test of your vision
  • The response of your pupils to light
  • Dilating drops in your eye to dilate your pupils, which allows the inside of your eye and retina to be examined in detail. This can be a little uncomfortable.
  • Ultrasound in some cases.

Your ophthalmologist needs to know your complete medical history.  Any health problems must be fully disclosed, as some conditions may alter the treatment of retinal detachment. The following must be disclosed to your doctor:

  • An allergy or bad reaction to antibiotics, anaesthetic drugs, other medicines, surgical tapes or dressings.
  • Prolonged bleeding or excessive bruising when injured
  • Recent or long-term illness
  • Any family history of eye problems
  • Psychological or psychiatric illness
  • Excessive scar formation or poor healing of scars after previous surgery.

It is important to give your doctor a list of ALL your medicines (including homeopathic products and vitamins).  Please include the details of any eye drops.

Include long term treatments such as insulin, warfarin, aspirin and contraceptive pills.

For some days before surgery, you may be required to stop taking medicines that are likely to increase the risk of bleeding.  Some of these medicines include aspirin, blood thinners (warfarin, plavix, clopidrogel, ecotrin), cough syrup, large amounts of vitamins (especially Vitamin E), garlic tablets, anti-inflammatories, and hormone replacement therapy. Your surgeon will discuss this carefully with you and in some cases may need to discuss with any other doctors that have been treating you for other conditions.

TIMING OF DETACHED RETINAL TREATMENT

Urgent treatment may be necessary, depending on the degree and position of the retinal detachment.  Your ophthalmologist will advise whether surgery is urgent or if it can be scheduled for a time more convenient for you.

It is important to understand that if the retinal is torn and not yet detached, it may be possible to treat the tear with laser in the consultation rooms without the need for an operating theatre.

If the retina is already detached, the condition is more serious and will normally need an operation to repair the detached retina.  This is done in the operating theatre.

The decision to have retinal surgery should be made after full discussion with your ophthalmologist. The decision to surgery is yours, and you should take as much time as possible while recognising that your case may be urgent.

Your ophthalmologist will be pleased to discuss the benefits, risks and limitations of retinal surgery, and the urgency of your case.  Keep in mind that a retinal detachment is serious condition, and repairing some types of retinal detachments can be challenging.  The visual results of the repair are affected by many factors.  The most important factor which will determine the visual recovery is how much of the retina has been detached.  Retinal detachments involving the macula area may result in a degree of reduced vision even after the retina has been re-attached, as the cone receptors are very sensitive and may have been damaged by the retinal detachment.

Realistic expectations:  it is important to understand the type of surgery to be performed and to a realistic expectation about the outcome after surgery.

Consent form:  if you decide to have retinal surgery, you will be asked to sign a consent form. Please take time tom discuss any questions or concerns with your surgeon.

PROGNOSIS

Regardless of the type of operation, surgery provides a good chance of fixing the retinal detachment.  While operations to repair retinal detachments can be complex, they usually are successful. In some cases, repeat surgery is needed.

About eight patients in every 10 have acceptable results from one operation.  The remaining two patients in 10 may need a second or further operations.  Of every 100 cases of retinal detachment, about 95 can be repaired and some vision preserved.  In the remaining patients, some or all vision is lost in the affected eye because the detachment cannot be fixed.  If retinal detachment has damaged the macula, it is likely that high-quality vision will not return.

The amount and acuity of vision that remains after surgery depends upon the severity of visual loss before surgery.  If the vision is poor before the surgery ( meaning that the macula has probably been affected by the detachment), then the operation is not as likely to result in good vision.  Central vision may improve but will never be as good as it was before the retina detached.

SURGICAL TREATMENT OF RETINAL DETACHMENT

Retinal detachment surgery is major eye surgery.  Surgery is often urgent because the problem needs to be fixed before the macula (a part of the retina responsible for high-quality central vision) is damaged or before further vision is lost.  Some cases are less urgent and can be delayed for at least a few days.

Scleral buckle surgery and vitrectomy are the two procedures mostly used to treat a retinal detachment. Scleral buckle surgery may be used in combination with vitrectomy.

  1. Scleral buckle surgery:  the surgeon uses small sutures to sew a silicone band or “buckle” to the outside of the eye at the point of retinal detachment.  The band gently makes an indent in the eye and pushes the retina back into contact with the choroid layer.  The band is placed behind the muscles that move the eye and is not visible to other people.  The scleral buckle is usually permanent.
  2. Vitrectomy: this procedure is used to remove vitreous fluid that is pulling on the retina and sometimes to clear blood that prevents a view of the retinal detachment.  Through tiny incisions, small instruments are placed inside the eye to remove some of the vitreous and allow access to the retina.  This can help to relieve traction by the vitreous that led to the retinal detachment.An air or gas bubble is infused into the eye to push the retina back in place against the choroid.  Fluid under the retina is held in position postoperatively by the bubble’s pressure (gas tampondade)In some cases , silicone oil or other synthetic liquid is used instead of gas.  After the retina has healed, the silicone oil can be left in the eye or removed during another procedure.  If another synthetic liquid is used, it is removed either before the end of the operation or after several weeks during another vitrectomy procedure.Vitrectomy surgery is useful in vitreous opacity (for example, to remove blood in the vitreous that is causing poor vision) or if the retinal tears leading to retinal detachment are large.  Vitrectomy is often used if the eye has had previous cataract surgery.  If scarring has developed on the surface of the retina, vitrectomy enables the surgeon to peel away the scar tissue.

Additional procedures to help treat retinal detachment

The following procedures may also be used in combination with scleral buckling or vitrectomy.

Drainage of subretinal fluid:  the fluid trapped between the choroid and the retina may be resorbed naturally, without the need for drainage.  In some cases, however, the surgeon may need to drain the fluid during the reattachment procedure to improve the outcome.

Laser treatment (photocoagulation):  laser treatment can help to seal a retinal tear and prevent retinal detachment.  It also helps to stop or prevent bleeding of retinal blood vessels.

Cryotherapy:  to seal retinal tears, a thin metal probe cooled with nitrous oxide is applied to the outside of the eye.  The extreme cold freezes the retina and choroid around the tear.  As the area heals, it forms a seal around the tear and helps to reattach the retina to the choroid.

Pneumatic retinopexy:  a gas bubble is injected into the vitreous .  With the patient’s head in the correct position, the gas bubble presses the retina back into contact with the choroid layer.  As the retina heals, it reattaches to the choroid.  The gas bubble is absorbed over the following one to eight weeks, depending on the type of gas.  Importantly, the patient must carefully follow the surgeon’s instructions on head positioning.  Pneumatic retinopexy may be used as an alternative to scleral buckling or vitrectomy, but only in certain cases.

RECOVERY AFTER RETINAL DETACHMENT SURGERY

Procedures to reattach the retina are performed in a hospital or a day surgery centre.  Some patients go home the same day, but others may have to stay in hospital overnight or longer.

The operated eye is covered with a pad and protective shield.  A responsible adult should drive you home, and someone should stay with you for at least one day.

The eye may appear red and swollen during recovery.  Expect some soreness for four to eight weeks.  If tiny stitches have been placed, the surface of the eye may have a gritty feeling.  You may have flashes and floaters in your vision for some time.  Blurred vision usually resolves in a few weeks, but can last longer.  Do not rub or press on the eye.  Your ophthalmologist may advise that you wear an eye shield at night, especially if you are instructed to lie face-down to help position intraocular gas or liquid.

You may have discomfort and pain.

Your ophthalmologist may prescribe medication to relieve pain, assist recovery and reduce the risk of infection.

Depending on the type and extent of surgery, your ophthalmologist will advise about resumption of  work, driving and normal activities.  Wait six weeks or more before doing heavy manual work and lifting, or engaging in strenuous exercise or sports.

You will be advised about keeping your eye clean.  During recovery, avoid getting water in the operated eye while showering or bathing.

You may resume your usual diet, but if you drink alcohol, do so in moderation.

Drops are required for four to eight weeks after surgery.  During this time, one or two follow-up visits to your ophthalmologist are usually scheduled.  A new prescription for spectacles if often needed. It may be best to wait for two to three months after surgery before having a final test done by your optometrist.

Avoid contact sports or vigorous activities until the eye has healed.

Intraocular gas:  if intraocular gas is used to aid retinal reattachment, then you will need to position your head after surgery so that the gas rises to push on the retinal break.  Such “posturing” may be needed for seven days or more.

IMPORTANT NOTE ABOUT THE USE OF GAS IN EYE SURGERY: You must avoid air travel when a gas bubble is in the eye because the gas will expand at high altitude. This will cause high pressure in the eye, with pain and visual loss or permanent blindness. High pressure in the eye can also occur during car transport up a mountain. If pain occurs, stop the car and drive downhill until the pain stops. You should wear a safety bracelet that warns an anaesthetist to avoid a gaseous anaesthetic. Do not have an anaesthetic procedure or operation that requires anaesthesia without first telling your surgeon and anaesthetist about your eye condition. If only silicone oil has been used, you can travel by air or up a mountain.

COMPLICATIONS AND RISKS

While retinal detachment commonly causes total blindness in an affected eye if left untreated, it is also possible that treatment can lead to side effects.  Despite the highest standards of best practice, complications are possible.  All surgery has some degree of risk.

It is not usual for a doctor to outline every possible side effect or rare complication of a procedure.  However , it is important that you have enough information about possible side effects to fully weigh up the benefits and risks of surgery.

Most people having retinal surgery will not have complications.  If you have concerns about possible side effects , discuss them with your ophthalmologist.

The following possible complications are listed to inform and to to alarm you.  There may be other possible side effects that are not listed.

Risks of retinal surgery

  • After vitrectomy surgery and gas tamponade, cataract formation is common, unless the patient is young.  The risk of cataract after cryotherapy or scleral buckling is low.
  • Bleeding or infection in or around the eye.
  • Raised pressure within the eye
  • Inflammation of the operated eye
  • Very rarely, inflammation that involves the unoperated eye (sympathetic inflammation or sympathetic ophthalmia) can lead to impairment of vision or blindness in the unoperated eye.  Sympathetic ophthalmia is a treatable condition.
  • The eye focus is often changed and a new spectacle lens may be necessary when the eye stabilises.
  • Double vision that is usually transient.
  • Despite the best current treatment, vision may still be lost in the operated eye;  the risk of this is about one in 500 cases.
  • Rarely, loss of the eye.
  • Glaucoma
  • Scar tissue will sometimes form after surgery on the retinal surface.  If this tightens, it may start to lift the edge of the previously treated retina and a new retinal detachment may occur.  In some cases, this may require another procedure or procedures, especially if it is a threat to your vision.
  • While the eye is filled with air or gas, vision will be poor.
  • While not a complication, a common problem is that the retina fails to attach will, and further surgery may be needed.

Specific risks of scleral buckling

  • Change in the shape of the eye, causing near-sightedness
  • Eye muscle imbalance, causing double vision.  This may be corrected with lenses or occasionally surgery on the eye muscles
  • Perforation of the sclera during suturing of the buckle, causing retinal bleeding or damage to the retina.
  • If the scleral buckle causes infection or other problems, it may have to be removed.

Report, at once, any of the following symptoms to your ophthalmologist:

  • Temperature higher than 38 degree Celsius  or chills
  • Severe pain, tenderness or increased swelling of the eye
  • Blurred vision or double vision that persists
  • Increased redness of the eye
  • Nausea or vomiting
  • Black spots or a black curtain in your vision
  • Any concerns you have regarding your surgery.

See your ophthalmologist urgently for the following symptoms:

  • A sudden onset of floaters or flashes
  • A shadow in the peripheral vision that moves towards the centre, or
  • Sudden deterioration of vision in one eye.

People who only have flashes and floaters are usually seen within a few days.  Those with loss of visual field or central vision should usually be seen on the same day.