What are Synechiae? Causes, Types, and Treatment Options
What are Synechiae? Causes, Types, and Treatment Options
21 July 2024

Have you ever heard of the sticky tissue in your eyes? It sticks your internal surface part of the eye with each other and forms a scar tissue known as synechiae.

Synechiae are abnormal adhesions or connections in the eye that form a band of scar tissue, binding the two parts together. When the scar tissue, that sticky substance in the eye, joins the iris with the cornea or lens, it can restrict movement and make them dysfunctional, making you feel pain.

Synechiae should be treated on time; if not, it can damage your iris, cornea, and lens and cause you to lose your vision. It doesn’t allow the immune response of the eye to heal the failing part of the eye. Synechiae can be treated either medically or surgically.

We will give descriptive information about its causes, types, and possible treatments to diminish or free you from the synechiae.

What does Synechiae Eye Mean?

Synechiae in the eye means an eye defect with an abnormal connection, forming sticky scar tissue between the iris (a circular, larger part of the eye) and other parts, such as the cornea or lens. 

Scar tissue on the eye can impact the vision, not letting the individual parts of the eye perform independently. It can appear web-like, with small dots or strands showing the color, generally white, grey, black, or cloudy.

When the function between the iris and cornea or lens cannot be performed individually, this will make it difficult for the eye to move correctly. Consequently, the light cannot be passed correctly from the cornea and the iris cannot capture it properly. Then, the light passing from the iris to the lens does not work as normally, misleading the optic nerve to transfer the exact information to the brain. It would lead to blurry vision or permanent loss of vision if not treated on time.

Causes of Synechiae Formation

To prevent and manage synechiae, you should know how this can occur. Several conditions can cause synechiae formation, such as:

i) Inflammation or infection

Inflammation or infection in synechiae directly affects the uvea or iris of your eyes. If the inflammation is seen in the uvea, you might get uveitis, whereas in the iris, it leads to iritis.

These would trigger the immune response to fail the healing portion, forming the scar tissue known as synechiae.

ii) Trauma

Direct injuries to the eye from accidents or surgeries can cause synechiae. It leads to swelling, redness, or burns in the eye, leading to abnormal connections between the iris and other ocular structures.

iii) Cataract

A cataract is a cloudy formation in the eye that prevents the iris, cornea, and lens from functioning properly. It would block the flow of the aqueous humour (clear fluid), leading to intraocular pressure and causing glaucoma.

Symptoms of Synechiae

If you are in the urge to get synechiae, it shows the following symptoms:

1. Blurry Vision

Scar tissue can change the shape of the iris, affecting light entering the eye and creating blurred vision.

2. Eye pain

There will be pain in the eye when your iris cannot perform individually, creating pressure in the intraocular.

3. Light sensitivity

You might be sensitive to the eye as the iris is not positioned normally and the pupil might take a different form. A person with synechiae cannot cope in a bright environment.

4. Redness

A visible redness or bloodshot in the sclera and swelling in the eye can be signs of synechiae.

5. Change in Pupil Shape

The shape of the pupil (a small circle inside the iris) would be changed to an irregular shape. You can see that the pupil is a little expanded over the iris.

6. Lack of vision

Your vision in the eyes would be lacking due to improper fluid flow.

Types of Synechiae

Synechiae’s scar tissue would infect the iris, which would be connected to either the cornea or lens. With the involvement of connections between the iris and the inner surface of the eyes, the types of synechiae can vary. There are three types of synechiae 

  1. Anterior Synechiae
  2. Posterior Synechiae
  3. Synechial Peripheral Anterior Synechiae (SPAS)

Difference Between Anterior, Posterior, and SPA Synechiae

S.N. Features Anterior Synechiae Posterior Synechiae Synechial Peripheral Anterior Synechiae 
1. Location Iris to Cornea Iris to Lens Iris to Angle (where the iris meets the cornea)
2. Appearance Strands Dots Strands
Web-like connection or sheet Flakes membrane
3. Impact Unclear vision Unclear  vision Increased eye pressure
Irregular pupil shape Distorted vision 
Eye pain Pupil movement issues
4. Risk Glaucoma (damage to optic nerve) Iris bombe (swell) Glaucoma  (damage to optic nerve)
5. Causes Inflammation like uveitis or iritis Inflammation like uveitis  Long-term inflammation (uveitis or iritis)
Trauma in the front eye Trauma in the behind eye Trauma in the immune response

Synechiae Eye Treatment Options

Synechiae, untreated, would increase the intraocular pressure (IOP), disturbing the normal flow of aqueous humour (fluid) that helps nourish the eye and maintain its shape. This can be a risk factor for the development of cloudy eyes. Glaucoma can damage your optic nerve, causing your eye vision to be permanently closed if not treated on time.

Moreover, the adhesion of scar tissue to the anterior surface of the eyes leads to irreversible changes in the eye if not treated timely. You may also experience irregular pupil shapes, discomfort, and pain in the eyes. The treatment options for synechiae can be medication or surgery, depending on the diagnosis.

Synechiae Eye Treatment: Medication Options

1. Corticosteroid

Corticosteroid medications are available as eye drops, ointments, or injections. This therapy treats especially inflammation related to uveitis. It helps in reducing the inflammation to form new ones and manage existing ones. Corticosteroid medications help to decrease inflammation, preventing the formation of synechiae in the eye.

2. Mydriatic agents

Mydriatic agents are eye drops that prevent posterior synechiae. It would expand the pupil and then separate the iris from the lens. When the separation starts to take place, it reduces the risk of the iris being connected to the lens, preventing glaucoma and vision loss.

Additionally, it also helps break existing adhesions by allowing more space in the eye for better fluid circulation and reducing inflammation. Mydriatic agent medication may include:

  • Atropine
  • Cyclopentolate
  • Phenylephrine

3. Cycloplegics

Cycloplegic drops are used to paralyze the ciliary muscle of the eye. It temporarily paralyzes the ciliary muscle, helping the lens to be adjusted and focus the object. After that, the iris remains stable, separating it from the lens. This reduces scar tissue that is formed in the eyes.

 Common use of cycloplegics eye drops are

  • Atropine
  • Cyclopentolate
  • Tropicamide

4. Intraocular Pressure (IOP) Lowering Medications

As the intraocular pressure in your eyes increases, you will be facing

  • Glaucoma
  • Swelling iris
  • Unclear vision
  • Damage to optic nerve

This would not allow aqueous humour to outflow the fluid needed to moisturize your eyes and keep them healthy.

IOP lowering medication would decrease intraocular pressure, reduce the synechiae, and allow a proper flow of aqueous humour fluid in the eye.

Synechiae Eye Treatment: Surgical Options

1. Laser Treatments

In the laser treatment, it could make a small hole in the iris. When a hole is made, it helps decrease the intraocular pressure, preventing the eyes from forming synechiae. This treatment takes place in cases of angle-closure glaucoma.

2. Surgical Removal

There might be some severe cases of synechiae where various techniques and equipment are used based on the location and extent of the adhesions in the eyes.

3. Cataract surgery

In some cases, synechiae may form clouds in the natural lens of the eye, known as cataracts. In such cases, with the help of surgery, the clouded lens is removed, replacing the artificial intraocular lens.

Conclusion

Synechaie would make a sticky adhesion inside your eyes between the iris and the cornea or lens. This sticky membrane can increase intraocular pressure, causing the aqueous humour fluid not to outflow properly.

When the fluid does not flow normally, it generates inflammation and diagnoses you with uveitis and iritis. This can lead to unclear vision, redness, or permanent vision loss in the eyes.

You can consult an optometrist at the Vision Concern eye clinic for medications and surgery to remove synechiae.

Yes, we provide emergency eye care for conditions like eye injuries, sudden vision loss, and infections. If you experience any urgent eye problems, please contact us immediately, and our team will assist you in getting the care you need.

Signs to watch for include blurry vision, floaters, sudden loss of vision, eye pain, redness, or sensitivity to light. If you experience any of these symptoms, it’s important to schedule an eye exam at Vision Concern Eye Clinic as soon as possible for early diagnosis and treatment.

If you’re experiencing blurred vision, headaches, or eye strain, it may be a sign that you need glasses or contact lenses. Our eye exams will help determine whether you need corrective lenses. We’ll also discuss your options based on your lifestyle and preferences, including glasses, contacts, or even refractive surgery like LASIK.