Central Serous Chorio-Retinopathy (CSCR)
Also known as Central Serous Retinopathy (CSR), CSCR is a common retinal disorder characterized by the build up of watery fluid underneath the retina. The retina is the “film of the camera”. It converts the light that you see into electrical signals to the brain.
What are the symptoms CSCR?
Fluid under the retina results in blurred vision and visual distortion. It causes reduced central vision which impairs reading, watching TV and driving. Distortion results in straight lines looking bent or wavy. Colour vision may also be impaired.
Who gets CSCR?
CSCR occurs most commonly in healthy young to middle-aged adults usually 20 – 45 years of age. It is much more common in males, but can occur in women especially during pregnancy.
What causes it?
The cause of CSCR is not known and it usually occurs for no obvious reason.
It may be induced by systemic steroids such as Prednisone or Cortisone. It can be caused by steroids in any form – tablets, steroid creams, nasal sprays, even injections into joints. It has even been reported in adults after rubbing steroid cream onto their children or pets.
For some reason CSCR is much more common in patients with what is known as a “Type A personality” These are motivated, ambitious, hard working people who push themselves to succeed, and it is more common in hard working, very successful people. It is more common in people who are stressed, but it is not known if removing the stress will result in resolution of the fluid.
How is the diagnosis made?
CSCR is diagnosed with a combination of clinical examination, colour retinal photographs and special scans. An OCT scan takes high resolution images at high magnification to see what layer of the retina is affected by the fluid. A fluorescein angiogram is a very commonly performed dye test where a nurse injects some special dye into a vein in your arm, and then photographs the dye passing through the retinal blood vessels to see where the fluid is leaking from.
What is the visual prognosis?
The prognosis for most patients with CSCR is relatively good. This is not a condition which will ever make you completely blind. In severe cases though it can result in mild to moderate loss of central vision which can impair the ability to read and drive with that eye. This usually requires either extremely severe CSCR or a long duration of fluid. Once the fluid has been present for more than 3 to 6 months, the fluid starts to do permanent damage to the retina, and once this damage occurs it cannot be repaired.
Even in those patients who experience rapid and complete resolution of the fluid, subtle visual problems may remain such as reduced colour vision or mild distortion.
Recurrences are common, and occur in 30 to 50 % of patients. In most people these occur within the first year, but they can occur years later.
There is no cure for CSCR and no medical treatment which is guaranteed to work. For those who require treatment, there are three options:
- Thermal Laser
- Photodynamic Therapy with Visudyne
- Intravitreal Avastin
1. Thermal Laser
The success rate for laser depends on how far away the leak site is from the centre of the macula.
If the leak is a long way away from the centre of the macula, laser treatment has a very high chance of success.
If the leak is very close to the centre, laser has a risk of resulting in a permanent dark spot in the vision.
If the leak is directly underneath the centre, laser is not possible as it would make the vision worse. See below for more information on laser treatment.
2. Photodynamic Therapy (PDT) with Verteporfin (Visudyne)
This involves and infusion of special dye (Verteporfin / Visudyne) followed by a special “cold” laser which activates the dye in the retina.
For those cases not suitable for thermal laser, this is a very good alternative. It will result in resolution of the fluid in approximately two thirds of patients. Unfortunately approximately one third of patients do not respond and the fluid persists. In some of these cases a second treatment can result in resolution of the fluid. There is a small, 1-4% chance that the PDT can make the vision worse, and this would be permanent. The significant disadvantage of PDT is that it is not covered by medicare and to purchase the Visudyne dye from the drug company costs $2000.
Avastin first became available in 2005 and has rapidly become the most common and most successful treatment for retinal swelling due to retinal vascular disorders such as diabetic retinopathy and in some patients with macular degeneration.
It works by reducing swelling in the retina. It turns off the leakage of fluid into the retina, and works in more than 90% of people with macular degeneration. It’s use for CSCR is much more controversial with some studies showing benefit and other studies showing no benefit. In our experience some patients show resolution of fluid with Avastin treatment, but some eyes do not respond at all. Each year there are more than half a million Avastin eye treatments performed in the USA. See below for more information on Avastin treatment.
AVASTIN treatment for CSCR
Avastin is administered as an injection into the eye. A tiny needle much smaller than a blood test needle is used. Just like a blood test, you do sometimes feel a momentary sharp sensation, but only for a second. A lot of strong anaesthetic eye drops are used, and some people do not feel the needle at all. A lot of antiseptic drops are used to prevent infection, and these do sting and irritate the eye, like salt water at the beach. Some people find the antiseptic drops very irritating and the eye can be very red, watery & irritated for 24-72 hours. Some people feel only minimal irritation for a few hours.
How long does the Avastin last?
It is important to understand that the Avastin is not a cure. The Avastin lasts in the eye for 4-6 weeks, and once it wears off the swelling will often return and re-treatment is required.
How long do I need treatment for?
The aim is to keep the retina dry and the swelling down until the swelling stops recurring. This means treatment with Avastin every 4-6 weeks until your body recovers by repairing the leak. In some people this occurs as early as 1 month. In others people it can take many months and some patients do not appear to respond to avastin at all. Fortunately there are newer treatments in development that can last many months and potentially one day new “slow release” technologies may allow treatment only once per year.
What are the risks of treatment?
There is a small risk of infection in the eye, with any injection procedure. This risk is around 1 in 1000. It is usually treatable if detected early. Rarely a severe infection which does not respond to antibiotics can result in blindness. It is therefore extremely important to contact us if you experience severe pain or vision deterioration.
What happens after the injection?
Hopefully over the week after the injection, you will notice the vision stops deteriorating and in many cases it actually improves. The vision usually improves a little further after each treatment, over the first three months. With regular follow-up, the visual prognosis for retinal vein occlusions is much better than it was even five years ago.
You will have some antibiotic drops to take, one drop four times per day for four days. A follow-up appointment will be made in four weeks to check your progress.
Focal retinal laser
How will the laser help my eye?
The goal of the laser treatment is to reduce the leakage of fluid from the abnormal blood vessels, which allows the retinal swelling to reduce. Persistent retinal swelling results in a slow decline in vision, so if the swelling can be reduced we can hopefully prevent further vision loss and preserve the best possible central vision.
There is still a chance that the abnormal blood vessels will continue to leak or may cause bleeding into the eye, but this risk is much reduced after the laser.
What is laser treatment like?
The laser is performed in a special room in the office. Local anaesthetic drops are placed in the eye. The laser is performed either sitting up looking into the slit lamp microscope, or lying back in the chair. You will see a lot of bright flashes of green light. Sometimes you will feel nothing at all, sometimes you will feel discomfort or a dull ache building up behind your eye. This settles very quickly once the laser is finished. Usually no pain killers are required, however sometimes an ice pack, or some paracetamol may be helpful.
What are the risks?
The only serious risk is if you look directly into the laser. The doctor will tell you to look far off to the side, so listen to the instructions and never look directly ahead at the laser.
What should I do after the laser?
Take it easy for the first 24 hours, with no heavy lifting or exercise. If the eye is patched, leave the patch on for 3-4 hours. If you have double vision after taking the patch off, the anesthetic may not have fully worn off.
Your vision should return to pre-treatment level after the dilation of your eye wears off, which may take up to 8-36 hours. If you have severe pain in the eye, a severe decrease in vision, increase in flashes or floaters, or dark shadowing of peripheral vision, call our office.
What follow-up is required?
It is extremely important to see the doctor for follow-up to assess the progress of the retina after the laser. Make a follow up appointment with our receptionist.