LENS PARTICLE GLAUCOMA

Lens Particle Glaucoma is a type of glaucoma that involves discharge of lens fragments into the aqueous humor and their subsequent migration into the anterior chamber of the eye.

The crystalline lens of the eye is located behind the pupil. It consists of an outer membrane, called the lens capsule, a nucleus in the center composed of primary lens fibers, and a lens cortex composed of secondary lens fibers that surrounds the nucleus. Lens particle glaucoma is a secondary glaucoma in which tiny fragments of lens material migrate into the anterior chamber of the eye through the pupil. Once there, these lens particles may be reabsorbed, flushed out, or become lodged in the trabecular meshwork. This, in turn, can cause a blockage of aqueous humor outflow from the eye and an elevation in intraocular pressure. Increased intraocular pressure is a major risk factor for optic nerve damage and the development of all types of glaucoma.

Slit lamp image, showing a spontaneous rupture of
the anterior lens capsule and the deep anterior
chamber with lens particles at the inferior angle.
Lens cortex material protrudes through the rupture
site. Source: Kim TH, Kim SJ, Kim E, Chung IY, Park
JM, Yoo JM, Song JK, and Seo SW. Spontaneous
Anterior Lens Capsular Dehiscence Causing Lens
Particle Glaucoma. Yonsei Med J. 2009 Jun;50(3):
452-454.

Three main factors are associated with the development of lens particle glaucoma.

Extracapsular Cataract Extraction – a surgical procedure that consists of removal of almost the entire natural lens, while the elastic lens capsule (posterior capsule) is left intact to allow implantation of a prosthetic intraocular lens. Phacoemulsification is a modified extracapular technique that emulsifies the lens with ultrasonic waves and aspirates the resulting particulate matter from the eye.
Neodymium:yttrium aluminumgarnet (Nd:YAG) posterior capsulotomy – a surgical procedure that is used to correct a complication called lens capsule opacification that is associated with extracapsular cataract extraction or phacoemulsification. Sometimes the lens capsule can remain clouded after cataract surgery and affect a patient's vision. Nd:YAG posterior capsulotomy effectively corrects this problem by using an Nd:YAG laser to cut a hole in the clouded back lining of the lens capsule, which allows light to pass through the membrane to the retina at the back of the eye.
Ocular trauma that perforates the lens capsule of the eye.

Lens particle glaucoma is a relatively rare condition, despite the fact that extracapsular techniques have become the method of choice by ophthalmologists for cataract surgery. Medical science is not entirely sure why this unexpected positive trend for patients exists. However, improvements in methodology and instrumentation for removing the lens cortex during cataract surgery may at least in part account for the lower-than-expected incidence of this type of glaucoma. Additionally, research suggests that preexisting difficulties with aqueous humor outflow that may or may not be sufficient to raise intraocular pressure to problematic levels on their own might be a contributing factor for the development of this specific type of glaucoma. Supporting this assertion, patients with open-angle glaucoma are less able to tolerate lens particle material retained in the trabecular meshwork compared to patients with a healthy aqueous humor outflow mechanism. Since patients diagnosed with both cataracts and glaucoma is a relatively rare occurrence compared to patients diagnosed with cataracts alone, one might expect that complications leading to increased intraocular pressure and lens particle glaucoma also would be rare following cataract surgery.

SYMPTOMS OF LENS PARTICLE GLAUCOMA

The presence and severity of symptoms will vary depending on the patient. Commonly observed symptoms include:

Decreased vision.
Pain.
Signs of conjunctival injection (non-uniform eye redness).
Lens cortex material and lens debris suspended in the aqueous humor.
Presence of hypopyon (puss), usually observed through gonioscopy.
Gonioscopy examination revealing accumulated debris in the iridocorneal angle.
Presence of circulating leukocytes and macrophages in the aqueous humor.
Onset of symptoms following ocular surgery or trauma.

Patients typically visit the ophthalmologist complaining of eye discomfort, redness, and/or impaired vision within days to weeks following an extracapsular cataract extraction, Nd:YAG posterior capsulotomy, or traumatic lens rupture. Examination will reveal inflammation, often manifesting as uveitis, and elevated intraocular pressure. Further signs include cataract remnants within the posterior chamber of the eye and fragments of white lens cortex material floating in the aqueous humor.

TREATMENT OF LENS PARTICLE GLAUCOMA

Treatment involves directly controlling inflammation and elevated intraocular pressure. Managing inflammation involves the use of topical corticosteroid treatments. In severe cases oral corticosteroids also may be prescribed. Intraocular pressure usually is lowered with the use of beta-blockers, alpha agonists, or carbonic anhydrase inhibitors. If these measures fail, surgical removal of the lens debris may be required to prevent it from becoming lodged in membranes and causing inflammation, causing permanent scarring to the cornea, and causing irreversible glaucoma.

REFERENCES:

Gamero GE. Glaucoma Associated with Lens Disorders. In: Zimmerman TJ and Kooner KS. Clinical Pathways in Glaucoma. New York: Thieme, 2001:201-204.

Matelis KH and Congdon N. Glaucoma. In: Kuhn F and Pieramici DJ. Ocular Trauma: Principles and Practice. New York: Thieme, 2002:174-175.

A number of visitors have written to me asking for recommendations pertaining to eye-care products and books for obtaining more information. I have joined with Amazon.com to create a dependable resource for books and products. You can find these materials at the Eye-Care Store.

Return from Lens Particle Glaucoma to Types of Glaucoma