Angle-closure glaucoma, which can be acute or chronic and is caused by a physical obstruction of the anterior chamber angle, is one of the many kinds of glaucoma. Severe ocular discomfort and redness, blurred vision, colorful halo rings surrounding lights, headaches, nausea, and vomiting are all signs of acute angle closure. IOP (intraocular pressure) is increased. To prevent irreversible vision loss, the acute disease must be treated right away with a variety of topical and systemic medications. Iridotomy is then the only option left.
Primary angle-closure glaucoma
Young individuals do not have narrow angles normally. The lens of the eye keeps expanding as individuals age. This growth causes the iris to advance in some people but not all, narrowing the angle. Family history, old age, and ethnicity are risk factors for developing narrow angles; the risk is higher in Asian and Inuit people and lower in European and African individuals.
The space between the iris at the pupil and the lens is likewise extremely small in those with narrow angles. Aqueous cannot travel between the lens and iris, via the pupil, and into the anterior chamber when the iris dilates due to forces pulling the iris centripetally and posteriorly (this action is termed a pupillary block). The angle is closed as a result of pressure from the ciliary body’s continuing secretion of aqueous into the posterior chamber, which pushes the peripheral iris anteriorly and causes an iris that bows forward (called an iris bombe). This closure prevents aqueous outflow, which causes an increase in intraocular pressure that is rapid (within hours) and severe (> 40 mm Hg) (IOP).
This illness, known as primary acute angle-closure glaucoma due to its sudden onset, is an ocular emergency that has to be treated right away. The plateau iris syndrome, in which the central anterior chamber is deep but the peripheral anterior chamber becomes shallow by a ciliary body that is moved forward, is one example of a non-pupillary block mechanism.
If the incident of pupillary block recovers spontaneously after several hours, typically after sleeping supine, intermittent angle-closure glaucoma develops.
Any person with narrow angles who has pupillary dilatation (mydriasis) may cause the iris to enter the angle and develop acute angle-closure glaucoma. This development is especially concerning when systemic medications are administered that have the potential to dilate the pupils, such as cyclopentolate and phenylephrine, or when topical medicines are used to dilate the eye for treatment or an exam.
Is glaucoma a chronic illness?
If the angle gradually narrows, scarring between the periphery of the iris and the trabecular meshwork develops; the IOP steadily rises; this is known as chronic angle-closure glaucoma..
Comparable to open-angle glaucoma, this kind of glaucoma has similar symptoms. Some people have headaches, ocular redness, discomfort, or impaired vision, which subside after sleep. This may be because of sleep-induced miosis (pupil constriction) and posterior displacement of the lens by gravity. The angle is small when viewed, and peripheral anterior synechiae, commonly known as PAS (sticking of the peripheral iris and angle structure causing occlusion of the trabecular meshwork and/or ciliary body face), may be seen. IOP in the afflicted eye is often greater but might be normal.
Chronic Angle Closure Glaucoma: Causes and Predisposing Factors
Currently, it is unknown what causes chronic angle closure glaucoma. It can most likely be brought on by one of the following:
- Thickening of your iris compared to norms.
- A plateau iris with a roll on its side that prevents fluid from flowing
- A disproportionately large lens that prevents fluid from flowing normally in the eye
- Chronic angle closure glaucoma is more likely to affect certain persons than others. You may be more susceptible to developing this form of glaucoma if you have tiny eyes or lenses that are especially big. Some other risk factors include:
- Asian or Inuit
- Related to a person who has chronic angle closure glaucoma
Diagnosis of Angle-Closure Glaucoma
Acute: Clinical symptoms and intraocular pressure (IOP) measurement.
Chronic angle-closure glaucoma is identified by gonioscopy, which also reveals peripheral anterior synechiae and distinctive optic nerve and visual field abnormalities.
Acute angle-closure glaucoma is diagnosed clinically and by IOP monitoring. A cloudy cornea and friable corneal epithelium may make gonioscopy in the affected eye challenging.
Examining the opposite eye, however, reveals a small or occludable tilt. Something other than a diagnosis of primary angle-closure glaucoma should be considered if the opposite eye has a wide angle.
The appearance of peripheral anterior synechiae on gonioscopy and distinctive alterations to the optic nerve and visual field are used to diagnose chronic angle-closure glaucoma (see symptoms and signs of primary open-angle glaucoma).
Treatment for chronic angle-closure glaucoma?
Damage from glaucoma is irreversible; it cannot be repaired. Surgery and medication, however, aid in preventing additional damage. Laser or surgical reopening of the obstructed drainage angle is usually required for the treatment of chronic angle closure. To assist in regulating the eye pressure in the majority of patients, some eye-drop medication is also required.
LPI should also be administered to patients who have chronic, subacute, or intermittent angle-closure glaucoma. In order to prevent angle-closure glaucoma, individuals with a small angle should have immediate LPI even in the absence of symptoms. The advancement of chronic angle-closure glaucoma can be significantly slowed down if a cataract is present and has to be removed.
Similar to open-angle glaucoma, the condition can be treated with medications and surgery. If the angle is so small that further peripheral anterior synechiae could develop following the laser surgery, laser trabeculoplasty is generally contraindicated. Partial-thickness operations are typically not necessary.
Eyedrop medication, which is regularly used, lowers eye pressure. Some eye drops do this by lowering the quantity of aqueous fluid produced by the eye. Others lower pressure by facilitating improved fluid movement through the drainage angle. While glaucoma treatments can help you maintain your eyesight, they also carry a risk of negative side effects. Additionally, they may interact with other drugs. It’s crucial to provide all of your doctors with a list of all the medications you frequently use. If you suspect that taking glaucoma medication has caused any negative effects, be careful to discuss this with your eye doctor.
Never stop taking your glaucoma prescriptions or adjust them without first consulting your ophthalmologist or optometrist. Ask your doctor whether you need to have your prescription filled if you are going to run out of your medicine.
For the treatment of chronic angle-closure glaucoma, there are primarily two methods of laser surgery. Both of these facilitate fluid outflow from the eye by shifting the iris away from the drainage angle. These operations are often carried out in an outpatient surgical facility or an ophthalmologist’s clinic.
Iridotomy. The ophthalmologist makes a small hole in the iris using a laser. The drainage angle benefits from the fluid flow via this aperture.
Iridoplasty. The ophthalmologist shrinks the iris back away from the drainage angle using a laser.
In an operating room, certain glaucoma surgeries are performed. Through these techniques, the blocked drainage angle is either unblocked again or a new drainage channel is established for the aqueous humor to exit the eye.
Angle-closure glaucoma is a condition when a person’s lens is sufficiently big to force the iris up above the drainage angle. It is referred to as a cataract if the lens is also hazy. The lens may be taken out and changed with a tiny, transparent implant lens by your ophthalmologist. This may enable the drainage angle to reopen and assist in reducing eye pressure.
The iris may get permanently stuck to the drainage angle if it has been obstructing the angle for a long time. A synechia is a name for this link. It prevents the drainage of fluid from the eye. These connections can be severed, and the iris can be pulled away from the drainage angle, by your eye surgeon using microscopic devices within the eye. This could allow the eye’s aqueous drainage to resume.
Your eye doctor will do this by making a small flap in the sclera (the white of your eye). Additionally, he or she will produce a filtration bleb, which is a bubble (or pocket) in the conjunctiva, the thin membrane that is on the inside of your eyelids and the white area of your eye. It often cannot be seen since it is concealed under the upper eyelid. The flap will allow fluid to exit the eye and flow into the bleb. Your eye’s tissue in the bleb absorbs the fluid, which lowers eye pressure.
Devices for glaucoma drainage
A small drainage tube may be implanted in your eye by an ophthalmologist. The fluid is sent to a collection place (called a reservoir). This reservoir is made by your eye surgeon behind the conjunctiva. Following absorption into surrounding blood arteries, the fluid lowers ocular pressure.
Summary of chronic angle-closure glaucoma
Early on in its development, chronic angle-closure glaucoma frequently shows no symptoms. In fact, 50% of glaucoma sufferers are unaware of their condition! Regular eye exams might assist your ophthalmologist in identifying this illness prior to visual loss. How often you should get eye exams is something an ophthalmologist may advise.
Dealing with chronic angle-closure glaucoma
Successful glaucoma management requires collaboration between you and your doctor. Your glaucoma therapy will be recommended by your eye doctor. You are responsible for adhering to your doctor’s advice. About every three to six months, you should visit your ophthalmologist or optometrist. Nevertheless, this may change based on your treatment requirements. Speak with your doctor if you have any questions regarding your eyes or your treatment.
Which course of action is ideal for chronic angle closure glaucoma?
Both open-angle and closed-angle glaucoma can be successfully treated with surgery in addition to medication and laser therapy. Trabeculectomy, glaucoma drainage devices (tube shunts), and cyclophotocoagulation are a few of these procedures.
Is chronic angle closure glaucoma a medical emergency?
Glaucoma can eventually result in blindness if it is not treated but generally chronic glaucoma isn’t an emergency. But If you have sudden glaucoma symptoms, get to an eye care facility or emergency room as soon as you can. This is a medical emergency that could need to be treated right now.
Which glaucoma kind is the most severe?
Secondary glaucoma is a disease kind that can be brought on by specific medications and eye conditions. Closed-angle glaucoma, however, is most likely the disease’s most severe kind. It happens when the angle is suddenly blocked, which causes a quick increase in ocular pressure.
What is the average age at which glaucoma manifests itself?
If you are 40 years of age or older, you are most susceptible to acquiring glaucoma. But that does not mean that glaucoma cannot occur at other times. Anyone can acquire glaucoma, just like anyone else can.
Can you halt the progression of glaucoma?
Action Is Necessary to Prevent Vision Loss. Get a thorough dilated eye exam if you belong to a high-risk category to detect glaucoma early and begin treatment. The progression of glaucoma can be halted using prescription eye drops. How frequently you should have follow-up exams will be advised by your ophthalmologist.
How many glaucoma sufferers become blind?
If glaucoma is not treated, blindness may result. And regrettably, even among glaucoma patients who receive effective therapy, 10% still lose their eyesight. Loss of eyesight due to glaucoma cannot be recovered. Further eyesight loss may be stopped with treatment and/or surgery.