Introduction

Chandler’s syndrome (CS) is a rare, progressive disease that affects your eye; specifically, the frontal dome of your eye (cornea), the coloured part of your eye (pupil), and the drainage system of your eye (anterior chamber angles) due to abnormal changes within corneal endothelial cells (cells that line the inner layer of the cornea). CS belongs to a group of related eye disorders, called Iridocorneal endothelial (ICE) syndrome, which includes PIO (Progressive Iris Atrophy) and Cogan-Reese syndrome, with CS accounting for more than half of all ICE cases. Similarly, ICE syndromes possess one common denominator, abnormal behaviour and changes within the inner cell layer of your cornea, causing similar symptoms, with a risk of developing glaucoma in more advanced stages.¹ 

When examining the eye for CS progression, the biggest concern is glaucoma, high pressure within the eye, which can lead to damage and loss of vision.² Despite this, with early detection via methods such as gonioscopy. Gonioscopy is an optical test that examines the eye in great detail, allowing doctors to identify abnormal corneal cells.  With gonioscopy, patients can obtain an early, more rapid diagnosis and receive the correct treatment for CS. In turn, patients are able to access treatments to ease symptoms of CS and protect their vision.³

In this article, we will dive into the abnormal changes in the anterior chambers of the eye, and how doctors can harness methods, such as Gonioscopy, what they look for, and how early detection, predicting risks, and formulating the correct treatment plan in relation to the stage of the disease can change the landscape of patients living with CS.

What is the anterior chamber and what are its angles?

It’s fair to say that most of us have never heard about the anterior chambers within our eyes. Despite this, they play an integral role in our eyes. The anterior chamber is a small, fluid-filled space found between the cornea (the dome at the front of your eye) and the iris (the coloured part of your eye). The fluid found within this space is essential for nourishing the eye and maintaining its shape. The angle, located at the base of the anterior chamber, can be thought of like a sink, which helps fluid within the eye drain out, prevents fluid accumulation, and maintains normal eye pressure. 

In CS, abnormal changes within the cornea cells can spread to other parts of the eye, including the angle. When a buildup of abnormal corneal cells accumulates in the angle, the natural drainage system of the eye is unable to work properly. Fluid is unable to be removed from the anterior chamber, and pressure is seen to rise within the eye.⁴ 

This buildup of pressure can often lead to more serious conditions, such as glaucoma, a condition caused by high pressure within the eye. Glaucoma is often a condition associated with more progressed stages of CS, and must be examined by a doctor for an accurate diagnosis.⁴ This is where the use of gonioscopy is important. 

What is gonioscopy?

Located at the back of the eye, the angle is often not visible to opticians and eye doctors through routine eye examinations, such as a torch or slit lamp.³

However, to properly visualise the angle, doctors can utilise specialised equipment to perform a quick test that visualises the angle in high detail, called Gonioscopy.

• Anaesthetic drops are placed on the eye, ensuring a painless procedure for patients
• A small, mirrored lens is placed gently on the front of the eye
• Mirrors in the lens can magnify the angle in great detail, allowing doctors to observe its structures

In relation to CS, Gonioscopy is essential for assessing the functionality of the eye's natural drainage system, specifically whether the angle is open, narrowed, or completely blocked by abnormal tissue. By assessing the degree of obstruction of the angle, doctors can evaluate the stage of the disease, choose an appropriate treatment for CS, and protect vision in the eye.

Gonioscopic findings in chandler’s syndrome

When doctors use gonioscopy to examine and evaluate patients for CS, they look for several signs. As aforementioned, CS affects corneal cells, causing them to behave unusually, change shape and size, and spread to other parts of the eye.¹ With this in mind, gonioscopy examines the inner cell layer of the cornea and compares it to what is usually seen in healthy eyes.

Below is a list of things doctors are actively looking for in CS:⁵

• Abnormal spread of corneal cells: A thin sheet of corneal cells spread to the angle within the drainage area
• Adhesion of the iris to the angle: Corneal cells can cause the iris and angle to ‘stick’ to each other
• Distorted iris surface: Folds and irregular patches are present in patients with CS, compared to the smooth surface of the iris seen in healthy eyes

When these changes are observed within the eye, they can explain why patients have developed glaucoma, depending on the degree of blockage the cells cause in the angle (drainage system). In turn, the more covered/blocked, the harder it is to remove fluid from the eye, creating high pressure. 

The importance of gonioscopic findings for patients

For patients, gonioscopy isn’t just a test – it is a procedure that is able to heavily influence the trajectory of life with CS.

• Early detection: Even before the rise in eye pressure, gonioscopy can visualise the angle in detail and show the presence of corneal cells beginning to close up and block the angle. Hence, the risk of glaucoma can be predicted
• Understanding the risk of glaucoma: Gonioscopy allows doctors to estimate the likelihood of patients developing glaucoma
• Guiding treatment options: With early diagnosis and risk assessment for glaucoma, gonioscopy results can help doctors decide the appropriate course of treatment. For example, based on the degree of progression, monitoring, eye drops, or a plan to implement for advanced treatments can be decided upon

In turn, gonioscopy is pivotal in controlling the progression of CS and can catch and address issues before they become a problem. 

Treatment options  

It must be noted that not all patients diagnosed with CS will develop glaucoma; however, it is crucial to monitor patients with CS to ensure it is caught at an early stage.

In turn, if pressure within the eye is seen to rise, treatment options focus on protecting the optic nerve from damage and preserving vision.

Treatment options for CS:⁶

• Eye drops: Used as the first line of defence in less progressed forms of CS. Eye drops are able to reduce fluid production
• Laser treatment: In more advanced cases, it is an option to help drain fluid from the anterior chamber. Thus, it reduces pressure within the eye
• Surgery: As a last treatment option, if eye drops and laser treatment fail, operations are available, such as:
  • Trabeculectomy
  • Tube implants

As CS is an incurable and lifelong condition, regular follow-ups are essential for patients diagnosed with CS at any stage. The nature of the disease is meticulous, with many patients unable to notice signs of CS until more serious symptoms later in the disease. In turn, regular check-ups and pressure measurements are essential to control the disease and prevent vision loss.  

Living with chandler's ssyndrome

As a patient, when being diagnosed with CS, it is natural to feel worried - it's in our nature. However, what many patients don't know is that CS is a manageable condition. Many patients are able to control the condition with appropriate medical treatment.

Here are some tips for living with CS:²

• Attend regular appointments
• Follow the advised treatment options, i.e., medications and prescriptions
• See a doctor if you suspect any changes/ new symptoms
• Keep healthy as a whole: Your eye health can be affected by other conditions, for example, high blood pressure and diabetes. In turn, make sure to lead a healthy overall lifestyle (e.g., exercise and eating habits) to minimise this risk

 Conclusion

While Chandler’s Syndrome (CS) is a rare and progressive disease, life with CS is manageable when patients are diagnosed early and correct treatment is provided. Gonioscopy offers a highly detailed, painless, and rapid physical examination, allowing doctors to inspect the eye for changes, such as abnormal corneal cells, specifically those that affect the anterior chamber angle, and compare them with those of healthy cells. When abnormal corneal cells are observed in this area, doctors are able to define the stage of the disease and predict the risk of glaucoma, one of the most concerning advanced symptoms of CS. In turn, gonioscopy is able to allow for early detection and prediction of glaucoma, helping doctors and patients make informed decisions about the most appropriate treatment options to ease symptoms and protect their vision.