Cataract Surgery overview © Michelle Baker This overview provides general information related to Cataract Surgery and does not take into account your personal circumstances
CATARACT SURGERY INFORMATION SHEET
Cataract Surgery
TABLE OF CONTENTS What Is A Cataract? What Causes A Cataract? Common Cataract Types What Are The Symptoms Of Cataract? When Is Cataract Surgery Indicated? What Is The Success Rate Of Cataract Surgery? What Pre-Cataract Surgery Assessment And Planning Is Needed? Ocular Considedration(s) Medical Consideration(s) What Investigations Are Needed Before Cataract Surgery? What Are The Vision And Spectacle Options? First Consideration Standard (Monofocal) Lens Multifocal Lens Extended Depth Of Focus (EDOF) Lens Second Consideration Toric Lens Third Consideration Monovision How Is Cataract Surgery Done? What Should I Expect On The Day Of Cataract Surgery? Before Cataract Surgery During Cataract Surgery After Cataract Surgery What Follow Up Do I Need After Cataract Surgery? Are There Any Side Effects From The Cataract Surgery? What Are The Risks Or Complications With Cataract Surgery? Complications During Cataract Surgery Early Complications After Cataract Surgery Late Colmplications After Cataract Surgery Who Can I Contact If I’m Having Problems?
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WHAT IS A CATARACT?
The lens of the eye is a transparent and flexible structure in the eye which enables the eye to focus clearly on objects at varying distances. As you age your lens becomes less flexible, more opaque and thicker. Early on these changes in the lens manifest with a need for reading spectacles, usually around 40 to 50 years of age, and then you may develop less contrast sensitivity in dim light. Lens opacification, known as a cataract develops slowly over many years. Cataract formation only affects the lens of the eye and does not affect other structures in the eye such as the cornea, iris, retina or optic nerve. This opacification of the lens blocks and scatters the light as it passes through the lens, preventing a sharply defined image from reaching your retina (the part of the eye which converts the light entering the eye into biochemical signals which are subsequently transmitted to the brain). As the cataract continues to develop, the opacity becomes denser and this leads to a decrease in vision. When symptoms begin to appear, vision may be improved through the use of new spectacles, stronger bifocals, magnification, appropriate lighting or other visual aids. In more advanced cases, cataract surgery is very successful in restoring vision. The image below is Claude Monet’s water lily pond, painted on the left in 1906 prior to developing cataracts and on the right in 1919 with mild cataract.
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WHAT CAUSES A CATARACT?
Cataract primarily forms as a normal part of ageing such as grey hair and wrinkles where they are a slowly developing process, from birth to death. As you age, the lens tissues no longer function as efficiently, leading to the buildup of oxidants and insoluble proteins in the lens. The combination of oxidation damage and protein accumulation is thought to cause the lens to become cloudy, opaque and accumulate yellow-brown pigment. Anything which disrupts the local lens environment can cause the lens to become opacified but there are risk factors for cataract development which may require more prompt treatment of the cataract before age-related changes occur. Risk factors for cataract development • • • • • • • •
Diabetes Steroids (including creams, inhalers and nasal sprays) Radiation exposure Ocular diseases: Acute angle closure glaucoma, Retinitis Pigmentosa, Uveitis, Keratoconus Ocular Trauma Prior ocular surgery: Retinal detachment surgery, glaucoma surgery Genetic conditions e.g. Down Syndrome Present from birth e.g. congenital cataract
COMMON CATARACT TYPES
Cataract is classified into 3 main types based on the anatomy of the human lens which correlates with how the lens opacity looks on examination. Patients commonly develop opacity in more than one area of their lens which can cause an overlap in the classification of cataract. 1. Nuclear cataract forms within the central zone (nucleus) of the lens with a central yellowish-brown colour and is associated with ageing.
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2. Cortical cataract forms within the lens cortex which surrounds the central nucleus, with white wedge-like opacities which start on the periphery of the lens and work their way toward the centre in a spoke-like fashion. 3. Posterior Subcapsular cataract forms at the back of the lens and is more common in people with diabetes, shortsightedness and those taking steroid medication.
WHAT ARE THE SYMPTOMS OF CATARACT?
Age-related cataract can begin to form around 40 to 50 years of age, which may manifest initially as less contrast sensitivity in dim light. By the age of 60, about half of all adults will have some early cataract formation, which may not be visually significant. By the age of 70, nearly everyone has some degree of cataract formation. The severity of cataract formation, assuming no other eye disease is present, is judged primarily by a visual acuity test. Cataract symptoms affect your quality of vision but some years may pass before a cataract interferes with your vision enough to seek treatment to improve your vision: • Blurred vision at distance or near (different types may affect distance greater than near or vice versa, see below) • Glare • Frequent change of spectacles • Coloured haloes around lights, especially noticeable when driving at night • Difficulty seeing in low light situations (including poor night vision) • Loss of ability to discern colours • Increasing near-sightedness or change in refractive status (including “second sight” phenomenon)
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• Double vision
WHEN IS CATARACT SURGERY INDICATED?
In the early stages of cataract development, the lens opacification causes subtle changes to vision, such as loss of contrast, glare and loss of colour perception, but not necessarily vision loss. Most people find that changing their spectacle prescription is enough to manage their subtle blurred vision in the early stages of cataract development. As cataracts progress, they cause a deterioration in vision. Cataract surgery is generally performed when your lens opacity is visually significant and affecting your activities of daily living. A cataract can be removed in the early stages of development, when it is causing changes to vision, but not necessarily severe vision loss. Sometimes cataract surgery is performed in patients with angle closure glaucoma and good vision, to maximally open the drainage angles. When deciding on the right time to have cataract surgery you also need to take into account the recovery process, making sure you can avoid certain tasks such as strenuous activity and swimming, usually for the first 6 weeks after surgery. Also, it is important to avoid travel during this time, to allow for prompt treatment, if complications occur. Considerations to be made in your decision process: • Is your cataract visually significant? • Does your cataract account for your level of vision? • Would the removal of your cataract likely lead to improved vision and an improved level of functioning? • Would the improved vision be enough to warrant the risk of complications which can occur with cataract surgery? • Could you tolerate cataract surgery? • Would you be able to follow post-surgery instructions and follow up care? • Is there another reason why I am having cataract surgery, such as to open my drainage angles?
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Answers to these questions are designed to lead you to make an informed decision if cataract surgery is warranted, and pre-surgery planning needs to be organised.
WHAT IS THE SUCCESS RATE OF CATARACT SURGERY?
The success rate of cataract surgery is high due to advances in technology, surgical techniques and intraocular lenses. Of every 100 operations to remove a cataract, at least 90% will result in significantly improved vision. If the eye is healthy, cataract surgery will restore excellent vision in up to 98 in 100 patients. Generally, after cataract surgery there will be an improvement in the colours you see, the sharpness, and the quality of your vision. If you wear spectacles for distance vision, cataract surgery may render you spectacle-free for distance and can sometimes reduce your dependence on spectacles for computer work and reading as well. In patients with glaucoma and narrow drainage angles, cataract surgery can widen the drainage angle, improving the drainage of aqueuous humour (natural fluid in the eye) and lower the intraocular pressure. Furthermore, if you have open angle glaucoma, minimally invasive glaucoma stents e.g. Hydrus, iStentW can be inserted at the time of cataract surgery, to better control the intraocular pressure and reduce the dependence on longterm glaucoma drops.
WHAT PRE - CATARACT SURGERY ASSESSMENT AND PLANNING IS NEEDED?
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OCULAR CONSIDERATION(S)
The front surface of your eye can be affected by contact lenses, dry eyes and some eye conditions. If you have any of these conditions I often need to bring you back for repeated measurements to ensure I can calculate the correct intraocular lens to obtain optimum vision outcomes. If you wear contact lenses, you will be asked to leave them out for at least 3 weeks before having your biometry scan. Please disclose if you have had any previous laser vision correction with Excimer laser (eg LASIK or PRK) as this affects the calculations which are used to determine the strength of the intraocular lens implant to be inserted in your eye. It’s important to identify any signs of pterygium before cataract surgery. A pterygium is a growth on the ocular surface caused by UV exposure which alter the curvature of the eye, and can cause astigmatism. It can be removed before cataract surgery, especially if a toric intraocular lens is to be implanted. A thorough ophthalmology examination, including dilating your pupils to assess the retina is essential to assess for any eye disease which could be causing a reduction in your vision.
MEDICAL CONSIDERATION(S)
A pre-cataract assessment of your general health will be carried out prior to your surgery. For this assessment, please have available an up to date list of your current medications, including blood thinners, and a brief summary of your medical history, if you are unsure. Your general health and suitability for anaesthetic will be assessed. Underlying medical conditions including heart disease, uncontrolled blood pressure and diabetes will need to be addressed prior to scheduling your surgery. You should continue any eye drops or tablets for your glaucoma, as prescribed. Please let me know if you have been on any medications for your bladder or prostate (e.g. Tamsulosin,
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Duo dart) as this can have long-term effects on structures inside your eye. Blood thinning medications, such as Aspirin and Clopidogrel/Plavix should also be continued, unless directed otherwise. If you take Warfarin this may need adjusting before your surgery to ensure its within the correct therapeutic range. You will receive instructions about fasting before your surgery.
WHAT INVESTIGATIONS ARE NEEDED BEFORE CATARACT SURGERY?
1. Biometry scan (measuring the length or your eyeball and curvature of your cornea) to determine the strength of the intraocular lens which best suits your eye and vision requirement. These meticulous high quality eye measurements sometimes need to be repeated before surgery for accurate results. 2. OCT scan of the macula (central part of the retina) to detect any macular problems, such as aged-related macular degeneration (AMD). You may also require the following test(s): • Specular microscopy (microscope for assessing the cells in the front window of the eye) and to diagnose certain diseases e.g. Glaucoma, Fuch’s Dystrophy • Topography scan of the cornea (assessing curvature of your cornea) to detect any corneal irregularity causing irregular astigmatism e.g. corneal disease, corneal surgery, eye injuries
WHAT ARE THE VISION AND SPECTACLE OPTIONS?
With cataract surgery, an artificial lens (known as an intraocular lens or IOL) needs to be chosen. Intraocular lens
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selection is an important process as it will determine your vision after cataract surgery. It is important to know that you have a choice of your vision outcome following cataract surgery. Your choice between having good distance vision or near vision, without spectacles, or being relatively spectaclesfree is based on your own lifestyle and visual demands, but everyone would agree that whatever distance you choose to focus on, it should be as clear as possible.
FIRST CONSIDERATION
Choosing the right intraocular lens is crucial to obtaining the vision you want after cataract surgery. The right intraocular lens is dependent on your lifestyle and expectations. Lifestyle considerations are occupation, hobbies, mobile phone, iPad, computer, television, driving, cooking, gardening, reading, mirror and makeup, bathroom basin, motivated personality. The standard (Monofocal) lens will only provide focus at one distance e.g. whether you want clear distance vision without spectacles or clear near vision without spectacles. If you choose want good distance vision you will need reading spectacles and you may still need spectacles for fine focus in the distance. If freedom from spectacles is a priority, a Multifocal lens is an option as they have a number of focal points to give clear distance and near vision. They do not work for everyone and may cause some vision quality disturbance such as loss of contrast, glare, haloes, starbursts, especially with night driving. These problems can be difficult to correct with spectacles. Another lens alternative is an Extended depth of focus lens which will provide some intermediate vision as well as clear distance vision. This intraocular lens is somewhat of a “middle ground” between the standard monofocal and multifocal lens.
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SECOND CONSIDERATION
The second consideration is whether you are like 40% of people with pre-existing corneal astigmatism, which can be corrected with a Toric Lens, which will provide you with the sharpest vision and reduce your dependence on spectacles. A Toric Lens is a safe and reliable method to correct astigmatism. You are born with astigmatism where the shape of your eye is more like an Australian rules football than a spherical soccer ball. Just like short-andnear sightedness, astigmatism can cause things to be out of focus due to the light rays entering your eye not being uniformly focused on your retina, thus reducing the sharpness of your vision. If you currently wear spectacles it’s possible that there is already a small amount of astigmatism correction in your spectacles. A Toric Lens, in the correct alignment, forms a complementary focus which neutralises the corneal astigmatism after surgery, which will provide the sharpest vision and reduce your dependency on spectacles. If you have astigmatism which is not corrected at the time of cataract surgery, you are likely to need spectacles more often in your day-to-day life. Are Toric Lenses more expensive? Manufacturer pricing for a Toric Lens is around $300 more than a non-Toric Lens. For insured patients, this cost is covered by your insurance fund and there is no extra out of pocket expense for using a Toric Lens. For self-funded cataract surgery patients the lens is provided at cost, but the difference means your cataract surgery is more expensive. This difference is similar to the cost of multifocal spectacles. Performing cataract surgery with a Toric Lens is the same as standard cataract surgery apart from having to rotate the Toric Lens after insertion. A standard lens does not need to be rotated to a specific position or angle. To the naked eye, a Toric Lens looks the same as any other lens but under the high magnification of the operating
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microscope, a Toric Lens has markers indicating the correcting axis. The intraocular lens must be precisely positioned so that the axis aligns with the steepest part of the cornea. Perfect alignment is crucial; for every 3 degrees of misalignment, the Toric Lens is 10% less effective at correcting astigmatism. An Image Guided System is used for precise Toric Lens placement. There are some risks with Toric Lenses: A Toric Lens may not fully correct the astigmatism and you may still need spectacles for distance. Further correction of this remaining astigmatism may not be possible. • If complications occur during cataract surgery, it may not be possible to insert a Toric Lens, and a non-toric, standard monofocal lens may need to be inserted instead. • The Toric Lens can rotate and a second operation may be needed to rotate the Toric Lens back into position for best vision, with the additional risk of further surgery.
THIRD CONSIDERATION
• Monovision (distance vision in one eye and near vision in the other): Some people want monovision to try and minimise the need for spectacles. If you choose this option, you may find it difficult to adjust, as only one eye is used at a time. You may still need spectacles for some tasks such as computer work or night driving. If you are considering monovision, it is a good idea to have a trial with contact lenses first – this can be discussed and organised with your local optometrist. Despite our best efforts is not always possible to guarantee absolute accuracy with vision outcomes following cataract surgery due to the lens calculations being 90-95% accurate. Sometimes, patients may still require moderately strong spectacles following cataract surgery despite correctly taken measurements and routine surgery. Even with a ‘perfect’ cataract surgery outcome, you will always need to buy spectacles again, for some activities.
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HOW IS CATARACT SURGERY DONE?
Cataract is treated with cataract surgery in an operating theatre as a day procedure. It is ususally performed under local anaesthetic. Despite there being various types of lens opacities, the surgical treatment of all cataract types is essentially the same. Cataract surgery involves removing your natural lens from its capsule and replacing it with a clear artificial intraocular lens which sits inside the capsule. Because the intraocular lens is inside your eye, your eye will look and feel the same, after you have recovered from your surgery. Cataract surgery is minimally invasive, requires a few small incisions and generally has a quick recovery.
WHAT SHOULD I EXPECT ON THE DAY OF CATARACT SURGERY?
The operation is usually performed in one eye at a time. You will need to fast for at least six hours before your procedure. Please allow four hours at the hospital. You will not be able to drive home on the day of your surgery, so you will need to arrange for someone to take you home and also to have a companion at home that night. Cataract surgery can be thought of as what to expect Before Cataract Surgery, During Cataract Surgery, and After Cataract Surgery.
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BEFORE CATARACT SURGERY
On the day of your procedure, please take all your usual medications, unless otherwise advised. Before the cataract surgery, you will receive the following: • Eye drops which make the pupil bigger. These can take up to 30 minutes to work. • Cannula inserted into a vein, usually at the back of your hand. • Eye drops which numb your eye prior to the anaesthetic injection. • The anaesthetist will give you a local anaesthetic injection around your eye to fully numb the eye, or if required, a general anaesthetic.
DURING CATARACT SURGERY
To reduce the risk of infection, povidone iodine antiseptic is used to clean your eye and eyelashes, a sterile drape will cover your face and chest, and a sterile clip will keep your eyelids open and your eyelashes away from the sterile field. If you have a local anaesthetic, you will be awake during cataract surgery, but you should not feel any pain. If you feel discomfort or pain, an additional local anaesthetic will be given. It is normal to notice bright lights or colours, and hear buzzing and beeping sounds, and feel cold water running down near your ear. You will need to lie flat and still on a bed for up to 45 minutes for the surgery. Cataract surgery involves removing the cloudy lens from its capsule that sits within, and replacing it with an artificial lens called an intraocular lens or IOL. An eye pad and a clear plastic shield will be placed over your eye, before you leave the operating theatre. If the unoperated eye does not see well, then only the clear shield will be placed on the operated eye, so that once the anaesthetic has worn off, it is still possible to see after surgery.
AFTER CATARACT SURGERY
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You will be discharged home from the hospital on the same day as the cataract surgery. Eye drops are not usually required in your operated eye until the day after surgery, unless you have glaucoma, where the drops may be continued and new bottles of glaucoma drop(s) are required. The eye pad and clear plastic shield remain on your eye until your review the next day.
WHAT FOLLOW UP DO I NEED AFTER CATARACT SURGERY?
Everyone will be reviewed one day after cataract surgery. The eye pad and clear plastic shield will be removed, and you can start your post-operative eye drops, after your review. Post-operative eye drops need to be instilled when lying down flat on one pillow to improve drop retention, and consist of an antibiotic eye drop (Chloramphenicol) which is to be instilled first, followed by a topical steroid antiinflammatory eye drop (Prednefrin Forte or Maxidex), which is to be instilled 5 to 10 minutes later, to prevent drop dilution. The bottles needs to be shaken first, before instillation. Both drops are instilled 4 times daily. You will need to continue your other eye drops (if any) with at least half an hour apart from these drops, also to prevent drop dilution. If you have diabetes, I will give you another drop to instill, a non-steroidal anti-inflammatory drop called Acular (Ketorolac) which is sto be instilled between the Antibiotic drop and before the Steroid drop. If the surgery was routine you will be reviewed at 1 week and 4 weeks after cataract surgery. Usually the Chloramphenicol drop will be ceased at your 1 week
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appointment and the steroid drop will continue until your 4 week appointment. Following your appointment 4 weeks after cataract surgery, provided everything is going well, you will be advised to see your optometrist for new spectacles to further sharpen up your focus at 6 weeks. It is important to avoid travel for 6 weeks following your cataract surgery, to allow for prompt treatment, if complications occur.
ARE THERE ANY SIDE EFFECTS FROM CATARACT SURGERY?
Temporary side effects are common after routine cataract surgery. These usually settle within a few weeks and include: – Red-eye: You may notice blood on the surface or bruising around the eye, which will gradually improve each day. – Grittiness: Your eye may feel gritty. This will settle within the first couple of weeks but minor grittiness can persist for a couple of months in some people. This will gradually improve with the eye drops. Lubricant drops can help relieve the grittiness, once the post op drops are finished. – Adjusting to the new lens: It takes weeks to adjust to the lens. Most people notice a big improvement in their vision soon after surgery, but it can still take time for the eyes to adjust to the difference in seeing through the new lens. For people needing distance or multifocal spectacles after surgery, you need to wait 6 weeks for the vision to stablise. You can wear ready made readers during this time. Side effects to look out for include vision deteriorating, increasing redness or eye pain.
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WHAT ARE THE RISKS OR COMPLICATIONS WITH CATARACT SURGERY? Complications following cataract surgery are uncommon and occur in only around 2%. Most complications can be treated, although sight-threatening complications may rarely occur (less than 1 in every 1000).
All surgical procedures are associated with risks. While every attempt is made to minimise risks, complications still can, and do happen, even in the most experienced hands, and a complication may have permanent effects, causing you to lose your vision. Complications can occur even if the surgery has been carried out perfectly. It is not usual to outline every possible side effect or rare complication with cataract surgery but it is important that you have enough information about possible complications to fully weigh up the benefits, risks and limitations of surgery. If your fellow eye is blind or has very poor vision you must carefully weigh the benefits versus the risks of cataract surgery in your ‘better eye’. There is a small risk of complications during cataract surgery. Serious complications following cataract surgery are uncommon but complications can occur early or late following cataract surgery. Often, these complications occur not because of anything you have or have not done. If at any point, you are concerned that you may have developed a complication following cataract surgery it is better to be safe, and be in contact so I can examine your eye.
COMPLICATIONS DURING CATARACT SURGERY Complications during cataract surgery are uncommon and most complications can be treated, although sight-
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threatening complications may rarely occur (less than 1 in every 1000) Bleeding: It is relatively common to have a little bleeding (subconjunctival haemorrhage) on the surface of the eye during surgery which may look serious and unsightly but the blood is located superficially under the conjunctiva and is of no clinical consequence. Heavy bleeding inside the eye (suprachoroidal haemorrhage) is a rare but potentially vision-threatening complication due to the accumulation of blood within a potential space within the eye which can cause permanent visual loss. This happens when a large blood vessel ruptures between the layers in the eye, causing a major bleed behind the eye. When there is a suspicion of suprachoroidal haemorrhage, the operation will be stopped immediately and all wounds will be closed. The operation can be resumed at a later date once the haemorrhage has settled. Injury to the iris: Less than 10% of people have an injury to the iris (coloured part of the eye). It may also result in an irregularly shaped pupil. Intra-operative floppy iris syndrome is the number one risk factor for this complication and generally occurs in men who have taken prostate-related drugs such as Tamsulosin. Generally, this complication is harmless but it can cause mild symptoms such as glare in bright sunlight. Damaged capsule (posterior capsule rupture): The capsule is the “bag” which surrounds the lens inside the eye. The capsule is an extremely thin structure, as thin as our hair, flimsy and transparent. In 2 to 3% of cataract surgery the capsule can tear or break. In most cases, the problem can be managed during the surgery itself. Occasionally you will be left without a intraocular lens and it will be put in at a later date, once the eye has settled. Posterior capsule rupture can lead to complications such as infection, glaucoma, persistent inflammation, cystoid macular oedema and retinal detachment which may require a second operation, such as retinal detachment surgery.
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Anaethesia (local and general): Rare but serious incidents can occur in relation to the administration of anaesthesia. The most extreme circumstances can be life-threatening.
EARLY COMPLICATIONS AFTER CATARACT SURGERY
Most early complications which do not involve another procedure and are not serious will settle over a few weeks, if treated appropriately. Occasionally, early complications may require a second procedure. The following complications listed are to inform you and not alarm you. There may be others that are not listed. These complications are monitored over time following cataract surgery. If there is progression to pain, decrease in vision, or any discharge from the eye, you are advised to promptly present for an eye examination. EALY COMPLICATIONS AFTER CATARACT SURGERY WHICH DO NOT INVOLVE ANOTHER PROCEDURE: Bruising of the eye or eyelids. This is quite common and settles within weeks Allergy to the post-surgery eye drops. This may cause redness and irritation of the eye and eyelid. This requires a change of eye drops. Raised intraocular pressure. The intraocular pressure can sometimes be elevated in the first few days after surgery. Measurement of the intraocular pressure is important during the immediate post-operative period after cataract surgery, particularly for those who have pre-existing glaucoma. This usually settles without any issues or treatment. However, if the eye pressure remains persistently high, it can be treated with pressure lowering eye drops or tablets. Fluid at the central part of the retina (macular oedema). This is usually mild and settles with a course of antiinflammatory eye drops. This is the most frequent
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complication after an uncomplicated cataract surgery occurring in 1 to 2% of cataract surgery with a peak incidence at about 6 to 8 weeks post-operatively. Risk factors are age-related macular degeneration or diabetic retinopathy, if the cataract surgery was routine. This is more common after complicated cataract surgery and if the lens capsule had been ruptured. Rarely, macular oedema can be severe and cause reduced vision in the long term. EARLY COMPLICATIONS AFTER CATARACT SURGERY WHERE TREATMENT MAY REQUIRE ANOTHER PROCEDURE: Retained piece of cataract: A bit of the lens can break off during cataract surgery and become lost in the front part of the eye. This happens in less than 10% of operations. It is usually harmless and the lens fragment often slowly degrades away without causing any consequences. However, surgical removal may be needed if the fragment is too large or causes persistent ocular inflammation. Refractive surprise: This is uncorrected long-sightedness or short-sightedness. Before surgery, based on your vision requirements, calculations are used to predict the most suitable intraocular lens. The calculations are up to 95% accurate, meaning there is a chance you may need spectacles for some tasks after cataract surgery, even though the refractive aim was to avoid this. This can usually be corrected with spectacles or contact lenses. However, if severe, further laser or surgical exchange of the intraocular lens implant can be considered. Infection Inside The Eye (Endophthalmitis): Of all the possible cataract surgery complications, endophthalmitis is one of the most feared. Microorganisms gain entry into the eye and may cause permanent vision loss, or rarely loss of your eye, despite treatment expediently with antibiotic injections into the vitreous cavity or surgery (1 in 2000 risk). Intraocular lens haptic out of capsular bag. This is treated promptly with surgical re-positioning of the intraocular lens.
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Retinal detachment. A tear in the retina requires laser treatment, usually in the outpatient clinic. A detachment of the retina is rare but more serious and requires retinal detachment surgery. Retinal detachment is a vision threatening complication which occurs when the retina separates from the layer underneath. Drooping of the eyelid (ptosis). This is usually transient. If it is permanent you will require ptosis surgery to lift the eyelid. Inflammation of the unoperated eye (sympathetic ophthalmia). This is a serious complication which may cause permanent total or partial loss of vision despite prompt treatment with steroids, in the unoperated eye. Suprachoroidal haemorrhage. This is a rare but potentially vision-threatening complication due to accumulation of blood within a potential space within the eye, which may cause permanent visual loss. It is very rare after cataract surgery, and occurs in less than 0.1%.
LATE COMPLICATIONS AFTER CATARACT SURGERY
Posterior capsular opacification: (Also called PCO) Fibrosis of the capsule, which is the thin membrane which supports the new lens inside your eye can occur gradually in 20 percent of people after cataract surgery, resulting in mistiness and blurriness of the vision after initially having clear vision following cataract surgery. Posterior capsular opacification impedes the passage of light rays through the lens to the retina. PCO is easily treated with laser surgery called a posterior capsulotomy. This creates a central opening in the middle of the fibrosed capsule which allows light to pass freely onto your retina and thus enables you to see clearly again. This laser procedure is a quick procedure performed in the consulting rooms, and is safe and effective, and you will have almost immediate improvement in vision. Retinal detachment: This complication occurs in 0.5
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percent of patients after cataract surgery. It is more common when there has been a complication during cataract surgery. The 3 main symptoms to look for are flashing lights, floaters, and a shadow or curtain obscuring your field of vision. If you notice any of these symptoms review is required, without delay. Retinal detachment will cause blindness if the retina is not put back into place, in a timely manner. A retinal detachment can only be treated with retinal detachment surgery. This surgery has a high success rate but your vision may be worse than before. Lens dislocation: Usually, the stability of the implanted lens in the eye is lifelong. There is no requirement to remove or to replace the lens, unless specifically indicated. However, on rare occasions, the capsular bag stability may weaken, resulting in lens subluxation (part of the lens is still in the correct location) or dislocation (entire lens is no longer in the correct position). The risk of this happening is higher in eyes following complicated cataract surgery, prior eye trauma and pre-existing eye conditions such as Pseudoexfoliation Syndrome. Treatment depends on how much the lens has moved, how much vision is affected and whether there is damage to other ocular tissues. If there is mild subluxation, and you are still able to see reasonably clearly, then there is no need to intervene. If the entire lens has dislocated, you will generally require surgery to remove the displaced lens and to replace it with a new one. Swelling of the cornea (corneal decompensation). Mild corneal oedema is expected after surgery; this is generally transient and will settle after a few weeks or so. Rarely, the oedema remains persistent and requires corneal graft surgery to improve vision.
WHO CAN I CONTACT IF I’M HAVING PROBLEMS? In case of emergency, it is possible to access an eye specialist 24 hours a day in South Australia.
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During business hours, depending on which site I have seen you at, contact Adelaide Eye Surgeons on 8361 3744 or Adelaide Eye and Retina Centre on 8212 3022. If you are concerned and its outside normal business hours, call me on my mobile (supplied with your post-operative information sheet). If you are unable to reach me on the above numbers, visit or call your local public hospital and ask to speak to the on-call ophthalmologist.
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