Congenital Glaucoma

DEFINITION

Congenital glaucoma, also called Primary congenital glaucoma (PCG) or Childhood glaucoma, is a rare eye condition present at birth or developing early in childhood. It results from improper drainage of the eye's fluids, leading to increased intraocular pressure (IOP), which can damage the optic nerve and cause permanent vision loss if not treated promptly.

CAUSES

• Most cases of PCG are sporadic without a family history of the disease.
• Genetic Factors: Congenital glaucoma often involves genetic mutations, such as changes in the CYP1B1 and LTBP2 genes. Family history and consanguineous marriages can increase the risks.
• Developmental Abnormalities: The condition is primarily due to developmental anomalies in the eye's drainage system, particularly the trabecular meshwork and anterior chamber angle.

TYPES

• True congenital glaucoma: Known as newborn glaucoma, the child is born with enlargement of the eyes, noticeable within the 1st month of life. The elevated IOP likely occurs during fetal life.
• Infantile glaucoma: Manifest symptoms between ages 1 and 36 months.
• Juvenile glaucoma: Patients with signs of elevated IOP that manifest between 3 years and adulthood.

SYMPTOMS

• Excessive Tearing (Epiphora)
• Sensitivity to Light (Photophobia)
• Involuntary Closing of the Eyes (Blepharospasm)
• Enlarged Eyes (Buphthalmos)
• Cloudy Cornea
• Bluish Discoloration of the Eyeball
• Reduced Vision

SIGNS

• Elevated IOP >21 mmHg
• Enlargement of the eye, cornea
• Haab Striae - Stretch marks on the cornea caused by high pressure

RISK FACTORS

• Family History: Genetic predisposition is a significant risk factor.
• Demographic Factors: Non-Hispanic black maternal race/ethnicity and certain maternal health conditions during pregnancy have been associated with an increased risk.
• Birth Weight: Low birth weight is also a risk factor.

DIAGNOSIS

• Eye Examination: Assessing the cornea, optic disc & cup ratio (>0.3 suspicious), intraocular pressure, and anterior chamber depth. For infants, it is mostly done under general anesthesia.
• Tonometry: Measuring intraocular pressure.
• Gonioscopy: Examining the angle of the eye.
• Pachymetry: Increased IOP causes stromal edema, resulting in a thicker than normal cornea, as thicker cornea may result in inaccurately overestimated IOP readings.

TREATMENT

The primary objective of treatment is to lower IOP and maintain optic nerve functionality.

• Surgical Procedures:
  • Goniotomy: Cutting into the eye's drainage angle.
  • Trabeculotomy: Creating a new drainage pathway.
  • Glaucoma Drainage Devices: Implanting a device to improve fluid drainage.

PREVENTION

Congenital glaucoma cannot be fully prevented, but early detection and treatment are crucial to prevent vision loss. Regular eye checkups and awareness of family medical history can help in early diagnosis. Preventive measures focus on early detection rather than prevention of the condition itself. However, understanding genetic risks and monitoring infants closely can aid in timely intervention.