Pediatric glaucomas may be associated with various ocular and systemic abnormalities that are present at birth. The following sections discuss a few of the more common conditions associated with glaucoma. For more detailed information on each entity, please see BCSC Section 6, Pediatric Ophthalmology and Strabismus, and Section 8, External Disease and Cornea.
Axenfeld-Rieger (A-R) syndrome is a spectrum of disorders characterized by anomalous development of the neural crest–derived anterior segment structures, including the anterior chamber angle, the iris, and the trabecular meshwork. Although this syndrome was initially separated into Axenfeld anomaly (posterior embryotoxon with multiple adherent peripheral iris strands), Rieger anomaly (Axenfeld anomaly plus iris hypoplasia and corectopia), and Rieger syndrome (Rieger anomaly plus developmental defects of the teeth or facial bones, including maxillary hypoplasia, redundant periumbilical skin, pituitary abnormalities, or hypospadias), these disorders are now considered variations of the same clinical entity and are combined under the name Axenfeld-Rieger syndrome.
Figure 11-3 photograph of an eye with Axenfeld-Rieger syndrome with prominent embryotoxon, iris hypoplasia, and corectopia.
(Courtesy of Jonathan Young, MD, PhD.)
Most cases of A-R syndrome are of autosomal dominant inheritance, but sporadic cases can occur. The disorder is bilateral, with no sex predilection. Classic clinical manifestations of A-R syndrome include posterior embryotoxon of the cornea (a prominent and anteriorly displaced Schwalbe line; see BCSC Section 4, Ophthalmic Pathology and Intraocular Tumors, for details on the histology) (Fig 3-11; also see BCSC Section 8, External Disease and Cornea, Fig 2-5) and iris adhesions to the Schwalbe line that range from threadlike to broad bands. The iris may range from normal to markedly atrophic with corectopia, hole formation, and ectropion uveae (see Fig 3-11 and BCSC Section 8, External Disease and Cornea, Fig 3-5). Table 11-9 outlines the differential diagnosis of A-R syndrome to help distinguish it from other conditions that involve abnormalities of the iris, cornea, and anterior chamber.
Approximately 50% of cases of A-R syndrome are associated with glaucoma, typically occurring in middle or late childhood. Glaucoma is thought to develop as a result of abnormal formation of the trabecular meshwork or Schlemm canal. The development of glaucoma correlates to the height of the iris insertion in the angle, not to the number of iris processes or the degree of iris abnormality. Treatment is generally the same as for an open-angle glaucoma; however, angle surgery may not be possible if there are many iris processes. Possible treatments for glaucoma associated with A-R syndrome include medications, goniotomy, trabeculotomy, trabeculectomy, tube shunt surgery, and cyclodestructive procedures.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.