- Primary congenital glaucoma (PCG) is a rare genetic disease usually diagnosed during the first year of life. It occurs because of developmental anomalies of the chamber angle that prevents drainage of aqueous humor, thereby elevating intraocular pressure. Its incidence is 1 in 10,000 live newborns in Western societies and 1 in 1,200 live newborns in the Arab-Bedouin population of the Negev region in Israel. Most cases of PCG appear to be sporadic. The cytochrome P4501B1 gene located within the GLC3A locus on chromosome 2p21 is mutated in individuals with PCG. The triad of epiphora, photophobia, and blepharospasm is classical for PCG. General anesthesia is usually required for an adequate examination of intraocular pressure, corneal diameter, optic disc, and axial length in young children. Congenital glaucoma is almost always managed surgically, with medical therapy being used only as a temporizing measure before surgery or when surgical intervention has repeatedly failed. At least 50% of eyes with PCG presenting at birth will become legally blind (visual acuity < 6/60). Patients with PCG require follow-up examinations throughout their lives.