pediatrics
Primary Infantile Glaucoma
Introduction
Primary infantile glaucoma is a rare developmental defect in the iridocorneal filtration angle of the anterior chamber that prevents aqueous fluid from properly draining from the eye. This obstruction increases the intraocular pressure, which, if untreated, damages the optic nerve. Infantile glaucoma can cause complete blindness if left untreated. (See also Overview of Glaucoma in adults.) The disorder occurs in infants and young children and may be unilateral or, more commonly, bilateral. Intraocular pressure increases above the normal range (10 to 22 mm Hg). Glaucoma can also occur in infants after trauma or intraocular surgery (eg, cataract extraction). Glaucoma associated with another ocular disorder, such as aniridia, Lowe syndrome, or Sturge-Weber Syndrome , is called secondary glaucoma. Fluid is produced in the ciliary body behind the iris (in the posterior chamber), passes into the front of the eye (anterior chamber), and then exits through the drainage canals or the uveoscleral pathway (black arrows). In primary infantile glaucoma or early childhood glaucoma, the affected eyes become enlarged because the collagen of the sclera and cornea can stretch because of the increased intraocular pressure. This enlargement does not occur in adult glaucoma. The large-diameter (> 12 mm) cornea is thinned and sometimes cloudy. The infant may have tearing and photophobia. If untreated, corneal clouding progresses, the optic nerve is damaged (as evidenced clinically by optic nerve cupping), and blindness can occur. Diagnosis is suspected when the symptom triad of blepharospasm (excessive blinking), photophobia (light sensitivity), and epiphora (tearing) is seen. The ophthalmologist is often able to measure intraocular pressure in the office or clinic; however, an examination under anesthesia in an operating room is necessary to obtain measurements of corneal thickness, axial length of the eyeball, and refractive error. These measurements further help confirm the diagnosis. Early surgical intervention (eg, goniotomy, trabeculotomy, trabeculectomy) is the mainstay of treatment. 