What is Lens-Induced Inflammation?
The term ‘endophthalmitis phacoanaphylatica’ was coined by Verhoeff and Lemoine in 1922. They used it to describe patients who had increased inflammation in their eyes—similar to endophthalmitis (an infection inside the eye)—after undergoing a specific type of cataract surgery. However, the first person to recognize this condition was Straub in 1919. It was later proven that this condition is immune-related because most patients reacted to an injection of lens proteins under their skin. This inflammatory response to lens proteins (which is known as uveitis) has had various names, like phacolytic glaucoma, phacogenic uveitis, phacotoxic uveitis, and phacoanaphylactic endophthalmitis. Although this type of inflammation is immune-related, it doesn’t involve certain types of immune responses (like those involving Immunoglobulin E or histamine, which are seen in type I hypersensitivity reaction). This is one reason why many now prefer not to use the term phacoanaphylactic endophthalmitis anymore.
Similarly, experts avoid using the term phacotoxic uveitis because lens protein has not been proven to be toxic to the eye. Lens-induced inflammation is believed to happen when lens proteins are exposed to the immune system, or when the body’s immune tolerance to lens protein changes. This can happen in different situations, like when lens proteins leak through an intact lens capsule in severe cases of cataracts, or when the anterior (front) lens capsule breaks in cases of traumatic cataracts or after cataract surgery.
In modern cataract surgery, it’s not common to see leftover matter from the cortical lens after cataract surgery. However, if there is any residual cortex after removing the cataracts, with or without an intact posterior (back) lens capsule, inflammation can occur. This inflammation may cause redness, pain, and light sensitivity in the eye. Generally, lens-induced inflammation can be controlled after cataract surgery or removal of any leftover lens matter. We’ll now discuss the causes, biological mechanism, signs and symptoms, other possible diagnoses and the treatment of lens-induced inflammations.
What Causes Lens-Induced Inflammation?
Lens-induced inflammation, an eye condition, is triggered by the immune system reacting to lens proteins. This usually happens when these proteins are exposed due to certain instances, such as:
* An advanced or mature cataract leaking lens protein even though the lens covering remains unbroken,
* Not all the cataracts being removed, and
* Injuries.
Lens-induced inflammation is found more often in developing countries, where medical facilities can be hard to access and there can be delays in getting cataract surgery. This inflammation also used to be more common with old-style surgical procedures, as pieces of the initial cataract remained. Advances in surgery techniques have reduced this inflammation.
Even with modern surgery, chronic inflammation of the eye or uveitis can occur if pieces of the cataract or its core are left behind in the front of the eye after a smooth surgery where the back of the lens remains intact. Sometimes, lens matter – partial or entire pieces of the cataract core and/or the outer cataract layer – can also creep into the jelly-like substance in the eyeball due to the breaking of the lens’ back or the weakening of the fibers that hold the lens. This could cause inflammation that depends on the size of the remaining piece, how much the eye was handled, the patient’s inflammatory response, and other health conditions. Common reasons for this inflammation after breaking down the cataract with high-frequency ultrasound include the lens matter falling into the jelly-like substance in the eyeball or a small unnoticed piece of the cataract core or lens matter in the lower corner of the front of the eye. This happens more in eyes with small pupils, loose iris, flaky cataract, hard cataract, and weak lens-holding fibers.
Injuries can cause the lens’ front to rupture and the lens proteins to be exposed to the tissues in the eye, leading to inflammation. Initially, inflammation of the eye or uveitis could be missed after the injury because of blood in the anterior chamber of the eye and swelling of the cornea. A small tear in the lens covering could later lead to a total cataract and severe inflammation. Lens-induced inflammation has been reported in cases of inflammation of the entire eyeball because of an injury, small and underdeveloped eyeball, bacterial eye infection in pneumonia, eye cancer, inflammation inside the eye, hereditary cataracts, and after repeated eyeball injections for diabetic eye disease in a patient who previously had surgery for hereditary cataracts.
In most of these cases, the covering of the lens has been damaged, leading to the lens proteins getting exposed. While a falling lens with an intact covering usually does not cause inflammation as seen in Marfan syndrome, lens-induced inflammation has also been seen in cases where the entire lens fell behind the eye even when the lens covering was intact.
Risk Factors and Frequency for Lens-Induced Inflammation
In a look at past patient cases at a specialist eye care center, fifty patients who came for cataract surgery were found to have a condition called lens-induced glaucoma. They made up 2.4% of the 12,004 patients who had cataract surgery between 2005 and 2011. Out of these patients, 78% had a type of lens-induced glaucoma called phacomorphic glaucoma, and 22% had another type called phacolytic glaucoma. Unfortunately, over 40% of these patients still experienced significantly impaired vision even after cataract surgery.
After the operation, pieces of the old lens left behind can cause lens-induced uveitis, which is a form of eye inflammation. There’s a case reported where uveitis was caused by a piece of lens left behind for as long as fifteen years after the cataract surgery.
Uveitis caused by cataract surgery, also known as phacogenic uveitis, is pretty rare because cataract surgery techniques have greatly improved. Most often, the diagnosis is made retrospectively, by looking back at past cases. Only six cases were identified in a retrospective study of 144 eyes diagnosed with lens-induced uveitis or another condition called phacoanaphylactic endophthalmitis. This lens-induced inflammation is usually a result of surgical or other types of trauma to the eye, which can cause inflammation anywhere from two days to fifty-nine years after the incident. When looking at the tissues under the microscope, a granulomatous inflammation pattern is seen around the damaged lens. According to a study by Thach et al., the choroid (which is a layer in the eye) was found to be involved in 76% of the cases.
Signs and Symptoms of Lens-Induced Inflammation
Lens-induced uveitis can be caused by advanced cataracts or damage to the lens capsule from surgery or other trauma. Usually, this inflammation appears within two weeks post-trauma or post-surgery. In rare cases, the inflammation might occur months or even years later due to fragments of the lens left behind after surgery. Patients are typically elderly and have had cataract surgery in one eye. Symptoms often include sudden pain and redness in the eye that hasn’t had surgery. Other symptoms usually relate to advanced cataracts, such as poor vision and a white pupil.
- Sudden eye pain
- Redness in the non-operated eye
- Poor vision
- White pupillary reflex
The exact symptoms and their severity can depend on factors like the lens’s composition, the extent of the lens fragments release, prior exposure to an immune trigger, and unique factors related to the individual’s genetics and health. Common symptoms include pain, red eye, light sensitivity, watering eyes, and decreased vision. Patients might also see floaters and experience blurred vision due to swelling in the retina. Advanced cases might cause severe inflammation that can lead to only being able to perceive light. Post-surgery inflammation can range from only light perception to near-normal vision.
- Pain
- Red eye
- Light sensitivity
- Watering eyes
- Decreased vision
- Floaters
- Blurred vision
Doctors often find inflammation in the front part of the eye while diagnosing this condition, but it can also affect the jelly-like substance that fills your eye. Symptoms might include swelling on the eyelid or cornea, calcium buildup on the lens capsule, high eye pressure, and even blood vessels growing abnormally.
If left untreated, this condition can possibly lead to severe complications, like inflammation of the inside of the eyes that resembles a serious eye infection, a shrunken and non-functional eye, or an extremely painful blind eye due to uncontrolled eye pressure. Sometimes, the eye’s internal pressure might drop dramatically, which can be caused by blood-filled fluid buildup, a decrease in blood flow to the eye or scar-like tissues.
Testing for Lens-Induced Inflammation
Taking pictures of the eye using a special microscope, or fundus camera, is a helpful way to monitor certain diseases. These photos make it easier to explain what’s happening to the patient and to keep an eye on how well treatments are working.
A technique called gonioscopy is also used to inspect specific structures within your eye. However, this method isn’t too effective in the early stages when the cornea (the clear surface of your eye) is swollen and makes seeing clearly into the eye difficult.
Another way to peek into your eye when the cornea is cloudy is with a tool called an ultrasound biomicroscope.
Methods like anterior segment optical coherence tomography and ultrasound biomicroscopy are particularly helpful when dealing with conditions such as uveitis glaucoma hyphema syndrome to identify improper placement of an artificial lens, instances where the iris (colored part of the eye) is sticking to the outer layer of the cornea, and causes for ongoing inflammation following cataract surgery.
It’s very easy to miss a case of lens-induced inflammation in the eye. An anterior chamber tap is essentially obtaining a fluid sample from the front section of your eye. Doing this can help your doctor spy giant inflammation-causing cells packed with lens material and differentiate between lens-induced inflammation and inflammation due to an infection.
An ultrasound B scan is invaluable in cases of advanced cataracts to search for foreign bodies inside your eye after an injury, to see if the lens has come loose, to identify abnormal bands causing tension, and cupping of the base of the optic nerve (the cable connecting your eye to your brain) in cases of a particular type of glaucoma due to a lens protein leak. It also rules out eye inflammation, inflammation affecting the whole eye, detached retina, and intravitreal cyst (a fluid-filled sac inside the eye).
Particularly in patients with eye inflammation following cataract surgery, imaging of the macula (the area at the back of your eye responsible for detailed vision), using optical coherence tomography, helps rule out a condition where there is swelling due to fluid-filled sacs and other possible diseases.
Treatment Options for Lens-Induced Inflammation
When the lens of the eye becomes inflamed, it’s important to detect and treat it quickly. Eye doctors use various techniques, such as taking a pressure reading within the eye, inspecting the eye using a tool called a gonioscope, and scanning the eye with ultrasound to further evaluate the condition.
The definitive approach to deal with this inflammation is to remove the cataract (a cloudy patch that develops in the eye’s lens due to aging or trauma). However, calculating the power of the artificial lens (intraocular lens; IOL) that is to be inserted can be tricky in eyes that have suffered trauma. For example, if the cornea of the eye with the inflammation is distorted, measurements from the other eye might be needed. Reducing the pressure in the eye preoperatively (before surgery) is also crucial. This is often achieved by administering certain medications.
Another approach to managing the inflammation is through steroids. These are typically given as eye drops, possibly as frequently as every hour. If the inflammation is severe, steroids may also need to be given systemically (throughout the body). Antibiotics are given to ward off potential infections, and medications are used to dilate the pupil and relieve spasms in the eye muscles, which can help reduce pain.
In young patients, removal of the clouded lens (aspiration) may be done manually or with the help of a device, depending on what facilities are available. Older patients might have surgery to remove the cataract. In all cases, it’s important to be cautious while performing surgery, especially if the back of the lens was injured previously. In cases where the lens inflammation is associated with advanced cataracts, further complications can be encountered like weakened zonules (the fibers holding the lens in place) or poor pupil dilation. Moreover, the innermost layer of the cornea might be compromised leading to delayed recovery from postoperative corneal swelling.
In surgeries where the cataract is very advanced leading to inflammation and high eye pressure, the cloudy lens matter should be fully removed to alleviate symptoms. However, avoiding aggressive surgical manipulation is essential to prevent further eye damage.
Postoperatively, certain medications can be used to reduce inflammation and manage complications like bits of the lens remaining lodged in the eye. If small pieces of lens material are left behind in the eye’s jelly-like substance (vitreous), they usually dissolve away over time.
What else can Lens-Induced Inflammation be?
Lens-induced uveitis, or inflammation of the eye, may have similar signs to several other conditions, both infectious and non-infectious. It’s crucial to distinguish between these to ensure proper treatment.
In older individuals, endophthalmitis – a severe eye infection – could be due to overall sickness and weakened immunity. Any history of hospital stays, drug injections, or intravenous infusions should also be considered. General health checks and tests related to the liver, kidneys, and lungs can help rule this out. It’s also important to rule out urinary tract infections.
If someone experienced eye trauma, they could develop bacterial or fungal endophthalmitis. Both conditions can cause hypopyon, a visible accumulation of white blood cells in the front of the eye. An ultrasound can detect these conditions by revealing unclear areas in the eye’s vitreous body. A history of injuries with contaminated tools or implements may suggest an infectious cause. Tests may be done on eye fluid to detect any bacteria or fungi.
Certain bacteria, Propionibacterium acnes, Staphylococcus epidermidis, and candida can cause eye inflammation. These bacterial infections can occur after cataract surgery and present with a variety of symptoms including granules, abscess, and inflammation of the vitreous in the eye.
A condition called sympathetic ophthalmia, which can cause bilateral eye inflammation, might have connections with lens-induced uveitis. This diagnosis may be made through indications of inflammation in both eyes, traces of fluid underneath the retinas, and blood vessel inflation. Ocular diagnostic imaging plays a significant role in this process.
Lastly, uveitis can result from collagen vascular disorders like ankylosing spondylitis and sarcoidosis. Proper history taking and tests can help rule these conditions out. It’s crucial that doctors correctly identify the cause of uveitis to ensure patients receive the appropriate treatment.
What to expect with Lens-Induced Inflammation
Generally, if an eye condition is detected early and treated promptly, the chances of maintaining good vision are high. However, if the inflammation in the eye goes without treatment for a long time, the outlook for restoring vision can be poor. This is due to several potential concerns such as swelling of the cornea, damage to the inner layer of the cornea due to inflammation, growth of abnormal blood vessels in the eye, increased pressure in the eye (glaucoma), swelling in the macula (the part of the retina responsible for clear vision), pull on the jelly-like substance in the eye (vitreous traction bands), inflammation of the blood vessels in the retina, and even shrinkage of the eyeball.
Operating on advanced cataracts can be challenging because of the hardness of the lens’s center (nucleus), the loose fibers holding the lens (lax zonules), and the fragile outer covering of the lens (friable capsules). Even after removing a cataract, increased pressure in the eye might still exist, requiring medical treatment and possibly additional surgeries.
Possible Complications When Diagnosed with Lens-Induced Inflammation
Inflammation caused by the lens and subsequent glaucoma may lead to undesirable results after surgery. It’s common to see inflammation after the operation, as well as secondary glaucoma and cystoid macular edema, which is swelling in the eye. Severe inflammation within the eye can lead to retinal vasculitis, a condition that causes inflammation in the blood vessels of the retina. Another potential issue is rubeosis iridis, which can occur before surgery and lead to a condition called hyphema afterward. The most serious complications are absolute glaucoma or phthisis, which is shrinkage and atrophy of the eye.
Potential Issues After Eye Surgery:
- Lens-induced inflammation
- Secondary glaucoma
- Cystoid macular edema (eye swelling)
- Retinal vasculitis (inflammation in the blood vessels of the retina)
- Rubeosis iridis leading to hyphema
- Serious complications such as absolute glaucoma or phthisis (shrinkage and atrophy of the eye)
Recovery from Lens-Induced Inflammation
For most individuals who have inflammation caused by the lens of the eye, the cure usually involves a procedure known as cataract extraction. The result of this operation is typically satisfactory, often aided by pre-operative use of antiglaucoma medications and topical and systemic steroids. These help in managing eye pressure and inflammation. It’s crucial to ensure that all lens matters are removed during the operation.
After the procedure, patients may still need to use topical steroids and antiglaucoma medications for a bit longer than usual cataract surgeries. Checking the back part of the eye, also known as the posterior segment, remains essential after the operation, as before. This is especially necessary when vision is not clear due to dense cataracts.
Patients who also have conditions like diabetes and high blood pressure need to be given special attention if oral steroids are administered. Additionally, after an eye operation due to injury, it is important to monitor eye pressure closely, evaluate the posterior segment, and examine the stitches in the cornea and sclera (the white part of the eye) in injuries that have been pierced through.
Preventing Lens-Induced Inflammation
Inflammation of the eye lens, often caused by conditions like cataracts, is more likely to happen as we age, and in places where getting medical care isn’t easy. Regular health check-ups, including eye exams, can be especially helpful in detecting cataracts early. It’s particularly important in areas where people may not have easy access to healthcare. Eye camps in less fortunate areas can identify cataracts before they cause conditions like phacolytic glaucoma (a type of eye pressure issue) and phacogenic uveitis (a kind of eye inflammation). Sadly, many older people still wait for their cataracts to become “mature” before seeking treatment.
Educating the general public through platforms like media, and sending healthcare workers to remote areas for adult screening, can help prevent this type of eye inflammation. On another note, traumatic cataracts – caused by accidents – can happen anywhere, in both developed and less developed countries. Wearing protective gear during risky activities can help prevent accidents that could harm the lens of the eye. Recognizing any damage to the lens early and getting timely surgery for traumatic cataracts could help preserve vision.
