what is retinitis pigmentosa melbourne vic

What is Retinitis Pigmentosa? Symptoms, Causes, & Possible Treatment

Retinitis pigmentosa is not a disease you’re likely to hear about often, yet it can cause significant visual impairment, to the point of legal blindness and disability. 

 

The Retina

The retina is the light-sensitive tissue lining the back of the eye. There are ten layers to the retina, one of these being the photoreceptor layer. Photoreceptors are the sensory cells that react to light entering the eye, converting this response into a neural signal that is then passed along to the brain. There are two types of photoreceptors – rods and cones, so named due to their shapes. Cones are found in greatest density at the centre of the retina, an area known as the macula. Cones are responsible for the discernment of fine detail and colour vision. When light levels are high, such as during daytime, our vision predominantly uses cones. Rods are located mainly in the peripheral retina and are responsible for our side vision and for sight during low light levels. Retinitis pigmentosa primarily affects the rod photoreceptors. So, what is retinitis pigmentosa

 

What is Retinitis Pigmentosa? 

Retinitis pigmentosa is a group of rare, inherited retinal eye diseases with a prevalence of around 1 in 4000 people globally. It is characterised by progressive damage and loss of the rod photoreceptors of the retina, eventually also leading to dysfunction of the cone photoreceptors. Retinitis pigmentosa may be an isolated eye disease or occur as part of a syndrome that affects other parts of the body, such as Usher’s syndrome. 

The characteristic symptoms of retinitis pigmentosa are night blindness and progressive loss of peripheral vision, eventually leading to tunnel vision. Due to the progressive nature of retinitis pigmentosa symptoms, the disease may not always be caught in its very early stages. The onset of the condition can vary between different subtypes of retinitis pigmentosa, from as early as within the first decade of life up to the fifties. Most commonly, retinitis pigmentosa will be diagnosed around childhood to young adulthood. 

As late-stage retinitis pigmentosa also affects the cone photoreceptors and is known to cause lesions at the macula, people with this condition may eventually begin to find their central vision deteriorates. While both eyes are typically affected to some degree, it is rare for people to completely lose vision in both eyes. Other eye findings commonly associated with retinitis pigmentosa are cataracts, short-sightedness (myopia) and astigmatism. 

Taking a thorough history of symptoms will help your optometrist or ophthalmologist diagnose retinitis pigmentosa. Several tests are able to confirm the diagnosis, including:treatment what is retinitis pigmentosa melbourne

  • Fundoscopy – having a clear view of the retina will identify characteristic signs, such as pigmentary changes, narrowed blood vessels, and a pale optic nerve
  • Visual field testing – this is useful to determine the extent of peripheral vision loss and monitor progression
  • Electroretinogram – electrodiagnostic testing measures the electrical activity of photoreceptors as an indication of their function

 

What is Retinitis Pigmentosa Caused By?

There are over 50 genes involved in retinitis pigmentosa. A mutation in one of these genes can affect a photoreceptor’s ability to produce a protein, whether a complete inability to manufacture a required protein or the production of a dysfunctional protein. Other types of genetic mutations may cause the production of a protein that is toxic to the photoreceptor. The inheritance pattern of retinitis pigmentosa may be X-linked recessive, autosomal dominant, or autosomal recessive. 

Genetic testing, whether as part of diagnosing retinitis pigmentosa or after the diagnosis has been made, may be useful to determine the likelihood of passing on a genetic mutation to your children.

 

Management and Retinal Surgery 

There is currently no known cure for retinitis pigmentosa, including retinal surgery. Low vision training, such as learning how to use a mobility cane or a guide dog, magnifying devices, or making modifications to everyday items, is an important part of living with retinitis pigmentosa. 

Some studies have indicated that a high dose of vitamin A supplementation taken daily can help to slow the progression of vision loss in adults. However, as there are several different subtypes of retinitis pigmentosa, this option may not be effective for most. It is not fully understood how vitamin A acts to slow the sight deterioration in this disease.  

There has been exploration into the use of gene therapy as a treatment option for retinitis pigmentosa, predominantly for conditions associated with a mutation of the RPE65 gene. However, as there are so many genes associated with retinitis pigmentosa, gene therapy currently has limited use in this disease.

Up until relatively recently, retinal surgery was not a viable option for treating retinitis pigmentosa. A device called the ARGUS II implant (no longer in production), was shown to have the potential to restore some sight to patients with late-stage retinitis pigmentosa. An electrode chip is implanted into the eye via retinal surgery, which stimulates the retina electrically after receiving signals from a camera mounted onto spectacles. More recently, there has been focus on the invention of an implant inserted directly into the brain, known as the Orion system. The device bypasses the damaged retina entirely, instead transmitting visual signals from the glasses-mounted camera directly to the brain’s visual centres. 

As these devices are still being developed, the mainstay of retinitis pigmentosa management remains as low vision training. 

Contact us at (03) 9070 3580 today for more info.

 

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.

signs of glaucoma melbourne

Detecting the Signs of Glaucoma and Its Treatment Options

Glaucoma is an eye disease characterised by progressive damage to the optic nerve of the eye. It can occur in just one eye and not the other, or be present in both eyes but more advanced in one compared to the other. The optic nerve is responsible for carrying the signals received by the sensory cells of the retina at the back of the eye to the visual processing centres of the brain. Glaucoma is actually quite common – around 2 out of every 100 Australians have the disease. So, what is glaucoma and how is it treated? And are there any early signs of glaucoma you can look out for?

 

What is Glaucoma

Glaucoma is one condition in a category of eye diseases known as optic neuropathies. As mentioned earlier, glaucoma is diagnosed when the optic nerve is found to suffer progressive damage and loss of retinal nerve fibres. While the exact underlying causes of glaucoma are still yet to be fully understood, we know that at a basic level, optic nerve damage in this disease occurs because the pressure inside the eye, called the intraocular pressure, is too high for the health of the nerve. Typically, the normal intraocular pressure range is quoted as 10-21mmHg (millimetres of mercury), however, we can often find that people with pressures within this range still experience glaucoma, while a person with an intraocular pressure slightly over 21mmHg can still demonstrate a healthy, robust optic nerve with no signs of damage.

symptoms and signs of glaucoma melbourne and mornington peninsula

The intraocular pressure of the eye is determined by the balance of fluid production versus fluid drainage inside the eyeball. This fluid is known as aqueous humour.

If the production of aqueous humour is excessive, or if its drainage from the eye is impeded or slowed in some way, it can result in elevated intraocular pressures. It is common and entirely normal for the pressures of the eye to be asymmetrical, within about 3mmHg of each other, and for pressures to fluctuate throughout the day. Controlling the intraocular pressures underlies all forms of glaucoma treatment.

 

Risk factors for developing glaucoma include:

  • Older age
  • Family history of glaucoma
  • Short-sightedness (myopia)
  • Diabetes
  • Sleep apnoea

 

The Signs of Glaucoma

Unfortunately, most glaucoma cases in their early to moderate stages present with no symptoms, lending this eye disease the nickname of “the sneak thief of sight”. Despite being such a relatively common condition, around 50% of Australians with glaucoma are actually unaware they have it.

The optic nerve and retina of the eye contain no pain receptors so there is no pain or discomfort directly due to damage of the nerve. A small subcategory of glaucoma known as acute angle closure glaucoma can present with some noticeable symptoms, such as a very painful, red eye with blurred vision. This occurs when the intraocular pressures suddenly escalate to very high levels. However, the majority of glaucoma cases fall under another subcategory called open angle glaucoma, which results in a slower, more insidious pressure rise.

Ultimately, untreated glaucoma results in permanent vision loss. This typically begins in our peripheral vision, which is another reason why most people are delayed in realising when something is amiss. Unlike our central vision, we are often less aware of subtle changes to sensitivity in our peripheral field of view. When it comes to glaucoma, by the time we begin to realise our peripheral vision has deteriorated, the disease is already likely in its advanced stages.

Because glaucoma progresses so slowly and subtly, it is important to maintain regular eye exams with an eyecare practitioner even when you feel nothing is wrong with your eyes or vision. This gives you the best chance of catching the disease in its early stages before any significant vision loss, allowing the optometrist or ophthalmologist to implement appropriate glaucoma treatment to slow or prevent further deterioration. An eye examination is able to detect any signs of glaucoma even if the condition is in its early stages, and will involve tests including:treatment signs of glaucoma melbourne

  • Tonometry – a measurement of your intraocular pressure; this may be taken multiple times to observe how your pressures may change over time
  • Ophthalmoscopy – directly visualising the optic nerve to assess its features, such as colour, shape, and size
  • Optical coherence tomography – a retinal scan that can take important measurements such as the thickness of the retinal nerve fibre layer to detect any areas of thinning and damage
  • Perimetry – also known as visual field testing, this is an assessment of the sensitivity of your peripheral vision and is very useful for monitoring glaucoma progression and any associated vision loss

 

Glaucoma Treatment

Modern glaucoma therapies are fortunately quite effective in most cases, and a lot of research is being devoted into developing new treatments, particularly in an area known as “minimally invasive glaucoma surgery”, or MIGS. There are currently no treatments that can restore the vision loss incurred from glaucoma, however, the aim of therapy is to slow or halt any further loss.

Treatment options include medicated eye drops, laser treatment, and surgery, all of which aim to reduce the intraocular pressures to a level that maintains the health of the optic nerve. Not all therapies will be suitable or effective for all patients, but your treating doctor will work with you to find one that is the most appropriate.

 

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.

 

macular degeneration treatment melbourne

What You Should Know About Macular Degeneration Treatment?

Age related macular degeneration is an eye disease with the potential to cause blindness. In fact, in Australia, it is considered to be the leading cause of legal blindness, contributing to half of all cases in our country. Unfortunately, even with retinal surgery, the loss of vision from macular degeneration cannot be completely reversed or cured, though with timely and appropriate macular degeneration treatment, it is possible to slow or reduce the risk of progression of the disease and further vision loss.

 

What is Macular Degeneration?

The macula of the eye is an anatomical area of the retina that encompasses your central vision. It differs from other areas of the retina in that it contains the highest density of cone photoreceptor cells, which are responsible for discerning fine detail and colour. This is why when we want to read or look directly at something, we turn our eyes to point the macula at the object of interest, making use of what’s considered the central vision. This is not to say that outside of the macula region we don’t perceive any vision – we’re just generally less attentive to our peripheral vision and unable to pick out fine details as effectively.

Because the photoreceptors of the macula are constantly responding to light and images entering the eye, they require a lot of energy and metabolic support. The retinal pigment epithelium, also known as the RPE, is the layer of cells that directly supports the photoreceptor layer of the retina, regulating the transport of nutrients and waste products as well as protecting the retina from damaging chemical reactions as a result of metabolic activity.

Age related macular degeneration and all its underlying factors are not yet fully understood, but it is known that damage to the retinal pigment epithelium plays a significant role in this disease. An eyecare practitioner, such as an optometrist or ophthalmologist, can see this during an examination as the formation of little bumps of accumulated waste material under the RPE, known as drusen. Eventually this leads to death (also known as atrophy) of these cells as well as the overlying photoreceptors reliant on the function of the retinal pigment epithelium, ultimately resulting in a decrease in vision in the affected part of the retina.

 

Macular Degeneration Treatment

surgery macular degeneration treatment melbourne and mornington peninsula

As mentioned earlier, there is no macular degeneration treatment that can totally reverse or undo the vision loss incurred once the disease has begun. However, there are options in macular degeneration treatment, including retinal surgery in very select cases, that aim to slow the progression of the condition and in some cases, has the potential to halt its deterioration, at least for a period of time.

There are two types of age related macular degeneration, and it’s important to identify which form is present in order to guide appropriate macular degeneration treatment and management. One is known as the dry form, which is characterised by the accumulation of drusen and subsequent atrophy. At this point in time, there is no known dry age related macular degeneration treatment. Instead, these cases are managed with nutritional and lifestyle advice in an effort to reduce the risk of further deterioration. This includes steps such as:

  • Quitting smoking
  • Implementing diligent UV protection for the eyes
  • A healthy diet of antioxidants, in particular zeaxanthin and lutein
  • Managing cardiovascular disease

The other type of age related macular degeneration is known as the wet form, or neovascular macular degeneration. This is defined by the formation of new blood vessels growing beneath the retina. These vessels are fragile and can leak blood and fluid into the surrounding tissues, causing scarring and significant vision loss.

Wet macular degeneration treatment options are a little better defined and often demonstrate good results in halting or dramatically slowing the deterioration of vision; in fact, there have been reports of some mild recovery of vision in certain cases. Injections into the eye of a medication known as anti-VEGF are the standard treatment for wet macular degeneration. This drug works by blocking the proteins produced in the eye that trigger the growth of new blood vessels. These injections are typically required to be administered multiple times over a certain period – some people require an injection every month to keep their condition under control, while others may be able extend their treatments to every 6 weeks or more.

Rarely are retinal surgery procedures used for the management of age related macular degeneration in modern ophthalmology. On occasion, a laser procedure known as photocoagulation may be employed alongside anti-VEGF injections in wet macular degeneration if the injections alone are insufficient to control the formation of new blood vessels.

During photocoagulation, a laser tool is used to purposely burn and scar small areas of the retina in order to seal off leaking blood vessels and prevent further uncontrolled vision loss. A problem with this treatment is that the laser scarring damages the retina by necessity, resulting in some degree of vision loss from the procedure itself.

Unfortunately, it is important to note that no macular degeneration treatment, including retinal surgery, can be guaranteed to be effective for all patients. As macular degeneration can begin with very subtle symptoms, it is important to maintain regular eye tests with your eyecare practitioner.

Contact us today at (03) 9070 3580 to schedule your next appointment!

 

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.

retinal tear causes melbourne

Retinal Tear Causes – How They Can Be Managed?

The retina is the light-sensing tissue lining the inside of the eye. Made up of ten layers of different types of cells, the retina is crucial for vision. Any damage to this structure from trauma or disease, including a severe retinal tear, can cause permanent loss of vision in that particular part of the eye. 

 

What is a Retinal Tear?

A retinal tear is exactly as it sounds – a rip or tear in the fragile tissue of the retina. This is different from a retinal detachment, where a section of the retina peels away entirely from the underlying structures of the eye, however, it is not impossible that a retinal tear causes a detachment, which must then be treated urgently with retinal surgery

The retina contains no pain nerves and so a retinal tear causes no physical discomfort or pain. Some instances of a retinal tear may in fact present with no symptoms at all, particularly if the tear is small or very far out in the periphery of the eye where we are less aware of changes to our vision. In other cases, a retinal tear causes symptoms including: 

  • A sudden appearance of floaters in the vision of the affected eye – these can be described as little black dots or spots, or cobwebs. Some people in fact think they’re seeing a swarm of tiny black insects before realising the floating specks are inside their own eye. 
  • Flashing lights in the vision – the medical term for this is photopsia, and often appears as a lightning arc out of the corner of your eye. The flashes may be recurrent and persist for some time.
  • Hazy vision – if the tear has disrupted some retinal capillaries, the resultant bleed into the space of the eyeball can cause a blurry patch in your vision. 

If the retinal tear causes a detachment you may notice more dramatic symptoms, such as the sensation of a dark shadow or curtain falling across part of your vision and obscuring that part of your sight. If you experience this it is important to promptly seek the attention of an eye specialist experienced in retinal surgery.

 

Retinal Tear Causes

Most instances of a retinal tear are idiopathic, meaning they occur spontaneously with no identifiable underlying reason. There are certain factors which may put you at a higher risk of developing a retinal tear, including:

  • Older age
  • A family history or retinal tears or detachments
  • A history of trauma to the eye or head
  • Myopia, also known as near-sightedness or short-sightedness, as this results in a thin retina
  • Lattice degeneration, which involves thinning of areas in the peripheral retina 
  • A history of an eye operation, including cataract surgery 

One of the common retinal tear causes can be attributed to a normal age-related change called a posterior vitreous detachment (PVD). The vitreous humour is a clear jelly-like substance that fills the back chamber of the eyeball, and is anchored to certain points along the retina.

As we age, the vitreous begins to liquefy, resulting in its solid molecular structure slowly collapsing. While this process is entirely normal, occasionally the adhesion between the vitreous gel and the retina is too tight and so does not separate easily as the vitreous liquefies. The tension on this anchor point may be enough to tug so hard on the retina that it causes a tear in the tissue, or possibly even a detachment. 

An eyecare practitioner such as an optometrist or ophthalmologist will often find a retinal tear incidentally during a routine eye exam. This can be achieved by using dilating eye drops to widen the pupil and utilising an illumination and magnification system to view the retina, such as a slit lamp biomicroscope or a binocular indirect ophthalmoscope. If there is a haemorrhage obscuring part of the retina where a tear or detachment is suspected, an imaging device such as an ultrasound may be required to view the retina behind the bleed. 

 

Retinal Surgery

The main determining factor when it comes to deciding whether retinal surgery is warranted for a tear is its potential to deteriorate into a vision-threatening retinal detachment. Retinal tears that are small, peripheral, and oriented in a certain way may be deemed low-risk, and therefore can be monitored carefully without intervention. Some tears in fact self-heal by naturally forming their own scarring, thereby resealing themselves. 

If a tear is thought to have significant potential to lead to a retinal detachment, also when considering a person’s other risk factors such as the presence of high short-sightedness, the eye specialist may recommend either a laser procedure called photocoagulation or a freezing technique known as cryopexy in order to seal the edges of the tear to prevent it from deteriorating.

In a way, both these treatments function like spot-welding, creating microscopic patches of controlled scarring that re-stick the torn retina to the underlying tissue. Photocoagulation is done under a topical anaesthetic in the ophthalmologist’s office and only takes several minutes. There is very little recovery time required afterward, if any at all, and many people resume their usual activities immediately. In the case of cryopexy, there may be a period of recovery over a couple of weeks.

It’s important to understand that successful treatment for a retinal tear doesn’t preclude you from experiencing another tear, either in the same or opposite eye. Your eye specialist will recommend you maintain regular and frequent eye exams with your eyecare practitioner. 

 

 

Note: Any surgical or invasive procedure carries risks. Before proceeding, you should seek a second opinion from an appropriately qualified health practitioner.