bubble_chart Overview

Congenital glaucoma is caused by developmental abnormalities during the embryonic period, leading to congenital anomalies in the angle structure or residual embryonic tissue that obstructs the aqueous humor drainage pathway. This results in increased intraocular pressure and continuous enlargement of the entire eyeball, hence it is also known as buphthalmos or developmental glaucoma.

bubble_chart Etiology

The increase in intraocular pressure caused by impaired aqueous humor outflow does not involve abnormalities in other ocular structures, except for the angle abnormality. The angle is covered by a translucent membrane over the trabecular surface, which is an impermeable surface membrane. This membrane obstructs the outflow of aqueous humor and is referred to as congenital mesodermal tissue remnants. It may be due to the failure of proper organization and arrangement of the angle tissues during development, the incomplete formation of the scleral spur, or the failure of the ciliary muscle to properly retract to the scleral spur, all of which affect the trabecular meshwork. As a result, the trabecular meshwork becomes compressed by muscle fibers, and the trabecular beams thicken, leading to the loss of spaces for aqueous humor flow.

bubble_chart Clinical Manifestations

Congenital glaucoma (congenital glaucoma) mostly exists at birth. It is a hereditary eye disease, manifested as an autosomal recessive inheritance, possibly occurring with the help of mutations. About 40% of congenital glaucoma presents as infantile glaucoma at birth, while those occurring between 3 years and under 30 years of age are called juvenile glaucoma.

(I) Infantile Glaucoma (infantile glaucoma)

This type of glaucoma can be primary or secondary to other congenital eye abnormalities and eye diseases. Congenital glaucoma occurring in the uterus can present typical symptoms at birth, such as enlarged eyeballs and corneal opacity.

1. Photophobia, tearing, and eyelid spasms: These are caused by early corneal edema accompanied by corneal irritation symptoms.

2. Corneal opacity: Initially, epithelial and subepithelial edema cause grade I milky opacity. When the stroma becomes edematous, the opacity becomes more pronounced. After intraocular pressure is reduced, the cornea may become transparent again, but in advanced stages, the opacity becomes permanent.

3. Corneal enlargement: Following corneal edema, if intraocular pressure continues to rise, the eyeball wall expands under pressure, causing the entire eyeball to enlarge continuously, appearing as "buphthalmos." The corneal diameter can reach about 12mm.

4. Rupture of the corneal Descemet's membrane: When the cornea expands, the Descemet's membrane develops horizontal curved or dendritic ruptures.

5. Enlarged optic disc cupping: Depending on the duration of the disease and the level of intraocular pressure, varying degrees of physiological cupping enlargement occur. In advanced stages, the cornea becomes more opaque, the anterior chamber deeper, the eyeball further enlarged, and the optic disc cupping expands irreversibly. Eventually, the eyeball atrophies.

(II) Juvenile Glaucoma

Juvenile glaucoma (juvenile glaucoma) refers to glaucoma that occurs under the age of 30 without causing eyeball enlargement. The clinical course is as insidious and slow-progressing as chronic simple glaucoma, but juvenile glaucoma is often more severe, with fluctuating intraocular pressure that may even rise rapidly. Rapidly progressive myopia in children and young adults should raise suspicion of glaucoma. High intraocular pressure in young people can expand the cornea and sclera, thereby worsening myopia. As the condition progresses, progressive optic nerve atrophy, enlarged optic disc cupping, and visual field defects may occur.

(III) Glaucoma Associated with Congenital Abnormalities

1. Marfan syndrome (Marfan), also known as arachnodactyly syndrome.

2. Spherophakia-brachymorphia syndrome, or Marchesani syndrome.

3. Homocystinuria (homocystinuria): A recessive hereditary metabolic disorder, with ocular manifestations mainly being lens dislocation and pupillary block leading to secondary glaucoma.

4. Sturge-Weber syndrome: The main ocular changes are glaucoma, choroidal hemangioma, and facial nevus flammeus.

bubble_chart Diagnosis

Early diagnosis of infantile glaucoma is crucial, and after surgical treatment, 80% of affected children can achieve normal intraocular pressure.

bubble_chart Treatment Measures

(1) Infantile Glaucoma

Congenital glaucoma is generally considered suitable for surgical treatment, as it is insensitive to miotics and difficult to control with medication. Preoperatively, carbonic anhydrase inhibitors such as levonordefrin and timolol are often required to reduce intraocular pressure, alleviate corneal edema, and constrict the pupil for easier surgical manipulation.

The main surgical approaches are goniotomy and trabeculotomy or trabeculectomy, with over 80% of patients achieving controlled intraocular pressure. Trabeculotomy is a rational choice for treating congenital glaucoma. Although the purpose of goniotomy is to incise the pathological thin membrane of the trabecular meshwork in the angle, it may also cut the trabecular meshwork itself, effectively lowering intraocular pressure.

(2) Juvenile Glaucoma

Juvenile glaucoma may be treated with 1% levonordefrin or 0.25%~0.5% timolol, either alone or in combination.