Pseudoexfoliation syndrome

Overview

Pseudoexfoliation syndrome (PXF or PEX) is a common age-related systemic condition characterized by the abnormal accumulation of fibrillar extracellular material in various ocular tissues, particularly in the anterior segment of the eye. It is most often identified during a routine eye exam when flaky, white deposits are seen on the lens capsule, iris, ciliary body, and other intraocular structures. Pseudoexfoliation is a major cause of secondary open-angle glaucoma—referred to as pseudoexfoliative glaucoma—which tends to be more aggressive and harder to control than primary open-angle glaucoma. Although the condition primarily affects the eyes, similar deposits have been found in other organs, suggesting a systemic component.

Causes

The exact cause of pseudoexfoliation syndrome is not completely understood, but it is believed to be a multifactorial disorder involving genetic and environmental influences. The most well-established cause is related to mutations in the LOXL1 gene (lysyl oxidase-like 1), which plays a role in elastin fiber formation and extracellular matrix remodeling.

Other contributing factors include:

• Age: Incidence increases with advancing age, typically affecting individuals over 60

• Genetic predisposition: A family history of PXF increases risk

• Geographic and ethnic factors: Higher prevalence in Northern European, Mediterranean, and Scandinavian populations

• Ultraviolet (UV) light exposure: May play a role in triggering or exacerbating the condition

• Oxidative stress: Damage to ocular tissues by free radicals may contribute to PXF pathogenesis

Symptoms

Pseudoexfoliation syndrome is typically asymptomatic in its early stages and is often discovered incidentally during an eye exam. When symptoms do occur, they are usually related to secondary complications such as glaucoma or cataracts. Common symptoms include:

Ocular Symptoms

• Blurred or decreased vision

• Increased intraocular pressure (IOP)

• Halos around lights, especially if glaucoma develops

• Ocular discomfort or redness in advanced cases

Visible Signs During Eye Exam

• Flaky, white deposits on the anterior lens capsule, pupillary border, or corneal endothelium

• Transillumination defects of the iris

• Poor pupil dilation due to iris rigidity

• Zonular weakness, which may lead to lens instability or dislocation

In many cases, pseudoexfoliation does not cause any noticeable problems until complications like glaucoma or cataracts arise.

Diagnosis

Diagnosis of pseudoexfoliation syndrome is made during a comprehensive eye exam. Specific signs and tests include:

Slit-Lamp Examination

• Detection of white, dandruff-like material on the anterior lens capsule and iris

• Peripheral iris transillumination defects

• Pigment dispersion in the anterior chamber

Tonometry

• Measurement of intraocular pressure (IOP), which may be elevated in cases of pseudoexfoliative glaucoma

Gonioscopy

• Evaluation of the drainage angle, which often shows pigment accumulation and signs of trabecular meshwork dysfunction

Ophthalmoscopy

• Assessment of optic nerve head for signs of glaucomatous damage such as cupping or thinning of the neuroretinal rim

Visual Field Testing and OCT

• Used to assess the functional and structural impact of elevated IOP and optic nerve damage

Treatment

There is no cure for pseudoexfoliation syndrome, but treatment focuses on managing intraocular pressure and preventing complications such as glaucoma and cataract formation.

Medical Therapy

• Topical IOP-lowering medications: Prostaglandin analogs, beta-blockers, alpha agonists, and carbonic anhydrase inhibitors

• Oral carbonic anhydrase inhibitors: For short-term control in severe cases

Laser Therapy

• Laser trabeculoplasty: Often more effective in PXF than in primary open-angle glaucoma due to increased pigmentation in the trabecular meshwork

Surgical Treatment

• Trabeculectomy or tube shunt surgery: For cases that do not respond to medications or laser treatment

• Cataract extraction: May be necessary earlier due to zonular weakness; surgeons must take special precautions to stabilize the lens

Monitoring

• Regular follow-up is essential to monitor IOP, visual fields, and optic nerve health

Prognosis

The prognosis for pseudoexfoliation syndrome varies depending on whether secondary complications like glaucoma are effectively managed. Without treatment, pseudoexfoliative glaucoma can lead to progressive vision loss and blindness. However, with early detection, regular monitoring, and appropriate management, most patients can maintain good vision.

PXF also increases the risk of complications during cataract surgery, such as zonular instability or posterior capsule rupture, but these can often be minimized with modern surgical techniques. Lifelong surveillance is recommended, as the condition can progress and affect both eyes over time, even if initially unilateral.