Category: Clinical Care

What is Uveitis
Uveitis is the inflammation of the uvea, the pigmented layer that lies between the inner retina and the outer fibrous layer composed of the sclera and cornea.
Uvea has 3 main parts:
The iris is the coloured part of the front of the eye, and its central aperture is called the pupil. Inflammation of the iris is called iritis.
The ciliary body is a ring of muscle, which lies behind the iris. Inflammation of the ciliary body is called cyclitis. The iris and ciliary body are often inflamed together (iridocyclitis).
The choroid lines the inside of the back of the eye, and supplies blood for the retina, the light-sensitive film of the eye, which form images. The retina is often involved in inflammations of the choroid. These inflammations are called choroiditis and retinitis.
Uveitis is classified anatomically into anterior, intermediate, posterior, and panuveitis based on the part of the eye primarily affected.
Uveitis can be acute (starting suddenly and going away within weeks) or chronic (coming on gradually and lasting for months or more). Acute uveitis is sometimes recurrent.
Uveitis can lead to secondary problems in the eye such as the lens of the eye becoming opaque called cataract, and the pressure of the eye going up called glaucoma.

Causes of Uveitis
Uveitis has many possible causes and may be linked to inflammations elsewhere in the body, but in many people, the cause is not found. Some of the common causes of uveitis are as follows:
Autoimmune
The immune system in our body protects us against foreign bodies like bacteria or viruses. In autoimmune disease a part of our body (self) is mistaken as foreign and attacked by its own immune system. The result is inflammation, which can involve the eye and cause uveitis.
Infection
Uncommonly infections may cause uveitis.
Trauma
This includes some form of eye injury and / or eye surgery.
Malignancy
Rarely malignancies either affecting the eye primarily or secondarily from other parts of the body can cause ocular inflammation.
Associated medical condition
Some patients will have a medical condition, associated with uveitis. eg: sarcoidosis, Behcet’s disease and ankylosing spondylitis.
Idiopathic
This means no specific cause or association with other medical conditions can be found.

Symptoms of Uveitis
Anterior uveitis causes a painful red eye, made worse by bright light, whereas posterior uveitis is painless and causes visual blurring and floaters. If not treated optimally uveitis may cause permanent damage to vision.

Treatment of Uveitis
The treatment of uveitis depends on the type and severity of the disease. Uveitis is mostly treated with steroids, drugs that reduce inflammation. A few specific types of uveitis caused by infections are treated with specific antibiotics.
Steroids can be administered either as drops, injections around or into the eye or in the form of oral therapy in severe cases.
If the steroids alone cannot control the uveitis or if a high dose of steroid is needed to control the inflammation then a ‘second line’ immunosuppressant drug may be introduced. These medications require close monitoring, by a uveitis expert.
Uncommonly a surgery called vitrectomy may be needed to diagnose and sometimes treat severe forms of uveitis.

What is a Cataract?
The crystalline lens is a transparent structure in the eye, situated behind the iris, and its main function is to focus the light on the retina. A cataract is a naturally occurring aging change of the crystalline lens. The lens becomes cloudy and loses its transparency. This process is usually very gradual and results in slow decrease of vision, colours appearing less vivid and some patients might be also aware of glare.

Who is affected by this condition?
As cataract is a normal aging change, most people above the age of 60 will have some degree of cataract. However, cataracts might be encountered at a younger age if there is previous history of ocular surgery, trauma, diabetes or inflammation. Rarely, cataracts may be hereditary or congenital (when one is born with a cataracts).

What is the treatment of cataracts?
In the early stages, the vision can be corrected by changing of the spectacles. However, the definitive treatment is surgical. With the advancement of technology, cataract surgery has become a much safer procedure. It is usually done under local anaesthetic as a day case.

What does the surgery entail?
The surgery is called phacoemulsification and intraocular lens implantation. During the operation a very small self sealing incision is made into the cornea. The lens is removed by using ultrasound (phacoemulsification). The ultrasound helps to break down the cataract into small pieces so that they can be cleared away through a small incision. Once the cataract is removed, a new foldable lens is inserted into the eye that will help focus the light into the retina.

When is the right time for the cataract operation?
Cataract surgery is an elective procedure and the decision when to operate is strictly individual. Once cataracts start interfering with one’s quality of life then it would be appropriate to consider the cataract surgery. It is no longer required to wait until the cataracts are “ready” or “ripe” to undertake the surgery. However, if the cataracts are not causing any symptoms and the patient can do all his/her daily activities the surgery can be deferred till later date.

Are there any risks/complications with cataract surgery?
Nowadays, cataract surgery is considered to be one of the safest operations however there are still small risks. The most serious risk is of an infection or a severe bleed that can lead to loss of sight. Fortunately this is extremely rare. It occurs in less that 1 in 1000 patients. Other more frequent, however, not as serious risks include inflammation, disturbance of the capsule, where the new intraocular lens should be implanted, or some lens fragments dropping to the back of the eye. All these can be successfully managed either conservatively or with further surgical procedures. Vitreoretinal surgeons are well trained in managing the surgical complications of cataract surgery.

What are eye floaters?
Eye floaters are usually seen when looking at a bright background, such as blue sky, snow or a computer screen. They may be of different shapes and colour and often shift downwards as the eyes get fixated on an object. Floaters are debris that form due to the natural ageing process of the vitreous (the jelly like structure that fills the inside of the eye).

Can floaters be harmful or a sign of a serious condition?
In the majority of cases floaters are benign and apart from causing visual disturbance to the patient they are harmless. However, there are a few occasions where floaters can be a sign of a serious condition. This includes conditions such as posterior vitreous detachment complicated with a retinal tear or a retinal detachment when floaters come on suddenly and therefore an urgent assessment by an ophthalmologist is required. Sometimes, inflammation (a condition known as uveitis) or an infection in the eye can cause the appearance of floaters. These will also require an assessment by an ophthalmologist.

Is there any treatment for floaters?
Majority of patients that have floaters get accustomed to them and can continue to lead a normal life style. Some patients however can never get used to them, and in a small subset of patients the floaters significantly affect their quality of life. In these cases, surgical treatment can be undertaken. The operation is called pars plana vitrectomy. It is similar to key hole surgery, and involves removal of the vitreous (jelly of the eye) where the floaters are present. With the advancement of technology this is done through very small incisions (up to 27G or 0.36mm) and normally do not require any sutures.

Can floaters be treated with other methods apart from surgery?
Laser treatment can be attempted for small floaters that are situated at the front part of the vitreous, gel, of the eye. However, this treatment is not always successful since it works by disruption of the floater into smaller pieces. The laser can cause some damage to the lens and to the retina. Due to its limited efficiency and risks associated this technique is not very commonly performed in the UK.

What are the risks of surgery?
As with any surgical procedure, the pars plana vitrectomy for floaters has a few risks. The very serious risk of severe infection or bleeding inside the eye is extremely rare (less than 1 in 2000). Some patients might develop retinal detachment following this procedure and would require further surgery. More common risk is the formation of a cataract, and therefore sometimes the procedure can be combined with a cataract surgery where the cataract is removed at the same time as the vitreous. All the potential risks and benefits of the operation should be discussed individually depending on the individual circumstances.

Anaesthesia for your operation.
The surgical procedure is usually performed under local anaesthetic as a day case, which means that the patient is fully awake during the surgery and can go home afterwards. A local anaesthetic is injected around the eye and for the duration of the surgery the patient is asked to keep still and lie on his/her back. The average time of the procedure is around 30-45 minutes. Alternatively, the surgery can be performed under general anaesthesia (the patient is asleep); however, that might require further investigations to assess the patients’ general health.

What is an epiretinal membrane?
An epiretinal membrane (also known as cellophane maculopathy and macular pucker) is a fine sheet of tissue that forms on the inner surface of the retina.

Who is affected by this condition and how?
Men and women are affected equally. Although the majority of the cases are idiopathic (i.e. there is no known reason for the development of the epiretinal membrane), it can also be linked to posterior vitreous detachment, previous laser treatment, inflammation, trauma etc. It is more common over the age of 60.

What are the symptoms?
Epiretinal membranes, when they are very fine and do not distort the architecture of the retina, do not cause any symptoms and do not require treatment. They do not necessarily progress.
If the epiretinal membranes are thicker and affect the retinal structure, they can cause blurred and distorted vision. Usually the symptoms are gradual and over time can worsen. Those patients might benefit from surgery.

How are epiretinal membranes treated?
The treatment of epiretinal membranes is surgical. The surgery consists of removal of the vitreous gel and gently peeling the membrane away from the retina. This surgery is called pars plana vitrectomy with epiretinal membrane peel. It can be combined with cataract surgery. Sometimes at the end of the operation a special gas bubble might be inserted. Following the operation, patients are also given some postoperative drops to use for approximately 4 weeks. The success of the surgery depends on the etiology of the epiretinal membrane and the duration of the symptoms. Although the majority of patients notice an improvement of their symptoms, it usually takes about 6 months to achieve the best result.

Anaesthesia for your operation.
The surgical procedure is usually performed under local anaesthetic as a day case, which means that the patient is fully awake during the surgery and can go home afterwards. A local anaesthetic is injected around the eye and for the duration of the surgery the patient is asked to keep still and lie on his/her back. The average time of the procedure is one hour. Alternatively, the surgery can be performed under general anaesthesia, the patient is asleep; however, that might require further investigations to assess the patients’ general health.

What happens if no surgery is undertaken?
Epiretinal membranes that cause no visual symptoms if left untreated occasionally (over a long period of time) might progress to cause distortion and blurred vision. All epiretinal membranes affect the central vision and therefore the peripheral vision remains intact.
If the epiretinal membranes have caused deterioration of the vision and no surgery is undertaken, the vision will remain blurred and/or distorted in the affected eye and might get worse overtime.

Macula and macular hole
The retina is the light sensitive tissue that lines the back of the eye. The very center of it, which allows us to see fine details and colour is called the macula.
Occasionally, one might develop a macular hole, which is a small defect into the center of the macula. This in turn causes blurred and distorted vision whilst the peripheral vision remains intact.

Who is affected by this condition?
Macular holes occurs approximately twice more frequently in women than men. People over the age of 60 are more frequently affected. There is approximately 15% lifetime chance of developing the same condition in the other eye. Although the majority of the cases are idiopathic (i.e. there is no known reason for the development of the macular hole), there are cases that can be linked to trauma, short sightedness and previous retinal detachment surgery.

What is the treatment of macular holes?
The treatment of full thickness macular holes is surgical and it is successful in restoring the macular anatomy in over 90%. The functional success of the surgery (the visual improvement) depends on the duration and the size of the macular hole.
The operation is called pars plana vitrectomy and can be combined with cataract surgery. This involves removal of the vitreous (the jelly), peeling a very fine layer from the retina (the internal limiting membrane) and inserting a special gas bubble. Patients are then asked to position face down overnight, no additional posturing is required. Whilst having the gas bubble in the eye (which lasts for approximately 4-6 weeks, and gets spontaneously absorbed), the patient would have poor vision in the operated eye and should not fly. Following the surgery, patients are also given some postoperative drops to use for approximately 4 weeks.

Anaesthesia for your operation.
The surgical procedure is usually performed under local anaesthetic as a day case, which means that the patient is fully awake during the surgery and can go home afterwards. A local anaesthetic is injected around the eye and for the duration of the surgery the patient is asked to keep still and lie on his/her back. The average time of the procedure is one hour. Alternatively, the surgery can be performed under general anaesthesia, the patient is asleep; however that might require further investigations to assess the patients’ general health.

What happens if no surgery is undertaken?
Full thickness macular holes can very rarely close spontaneously over time even if no surgery has taken place, this can lead to a visual improvement. However, in the majority of patients the central vision will remain poor and may further deteriorate. Macular holes affect the central vision only therefore the patient can still have good peripheral vision.

Retina and retinal detachment
The back of the eye is covered by a tissue, comprised of different layers, that is responsible for the conversion of light into neural signals and in turns it allows us to see. This tissue is called the retina.

The retina can come away from the other layers of the eye. This happens if there is a defect (a tear or a hole) in the retina that can allow fluid to pass through the defect and hence detaches the retina from the surrounding tissues. Most retinal detachments develop suddenly (although that is not always the case) and the patient presents with sudden onset of flashing lights, floaters and a dark shadow that obscures the vision. Rarely, retinal detachments can be asymptomatic. If retinal detachment is left untreated it normally leads to total loss of vision in the affected eye.

Who is affected by this condition?
Although retinal detachment is relatively common (one in 10, 000 per year) and it can occurs as part of normal age related changes in the eye, there are some people that have increased risk. People that are short sighted or have had trauma, previous cataract surgery, especially complicated or family history are at higher risk of getting a retinal detachment. It is also known that if one has had a retinal detachment in one eye, there is an increased risk of getting one in the other eye.

What is the treatment of retinal detachment?
The treatment is surgical. There are mainly two surgical approaches to treat retinal detachments – Internal and External.
The internal approach is called pars plana vitrectomy, which is a “key hole” surgery. It involves removal of the vitreous (the jelly of the eye), finding and treating the break of the retina that has allowed fluid to accumulate underneath the retina and then putting a special tamponade (either a gas bubble or silicone oil). If gas is used, the patient would not be able to fly and will have very blurred vision for a few weeks while the gas bubble spontaneously disperses. On the other hand, if silicone oil is used there are no restrictions on flying but a second operation is normally required to remove it. The surgeon will make the decision on which tamponade is best for each individual patient.
The second and less common approach is the external. The surgery is called scleral buckling with cryotherapy. It is usually the preferred method of surgery in younger patients. This involves applying cryotherapy to the retinal hole and then placing a silicone rubber (buckle) on the sclera (the outside wall of the eye). That in turns creates an indent inside the eye that helps with the resolution of the retinal detachment.
The success of retinal detachment surgery is approximately 90% with one surgical procedure. This is anatomical restoration of the architecture of the eye, it does not always correspond to full visual recovery.

Anaesthesia for your operation.
Retinal detachment surgery can be done under local or general anaesthesia. Usually, if a decision has been made to perform the internal surgical approach (pars plana vitrectomy) then the majority of cases would be done under under local anaesthetic as a day case. This means that the patient is fully awake during the surgery and can go home afterwards. A local anaesthetic is injected around the eye and for the duration of the surgery the patient is asked to keep still and lie on his/her back. The average time of the procedure is one hour.
If the surgeon has opted for the external approach then the preferred method of anaesthesia is general anesthesia. In this case the patient is asleep; however, that might require further investigations to assess the patients’ general health.