(A)

(B)

Fig. 19-31  (A) Axenfeld’s anomaly. Multiple iris processes have formed between the iris and

a prominent Schwalbe’s line. There is a broad area of iris adhesion to Schwalbe’s line (left).

(B) Axenfeld’s anomaly with dense iris adhesions that almost completely cover the trabecular meshwork. Particles of pigment are deposited along a very prominent Schwalbe’s ring.

(From Hermann M, and others: Published courtesy of Arch Ophthalmol 53:767, 1955. Copyright the American Medical Association, 1955.)

combination trabeculotomy/trabeculectomy, trabeculectomy with antimetabolites, or glaucoma tube procedure.

Pierre robin and stickler syndromes

Pierre Robin syndrome was originally characterized by micrognathia, glossoptosis, cleft palate, and cardiac and ocular anomalies.240 Recent studies emphasize the triad of retrognathia, cleft palate, and respiratory distress both from airway and brainstem abnormalities.241 Ocular disorders manifest as developmental glaucoma, cataracts, high myopia, retinal detachments, and occasional microphthalmos. There is sighnificant overlap of symptoms with Stickler syndrome,242,243 an autosomal dominant disorder characterised by progressive arthropathy, midfacial flattening, Pierre Robin anomaly or cleft palate, sensorineural hearing loss, progres-

sive myopia, pathognomonic vitreoretinal degeneration, and retinal detachment.244,245 Recent molecular studies have distinguished

two gene loci, expressed as Stickler syndrome with and without non-ocular features.246 The glaucoma in both Stickler and Pierre Robin syndromes is due to isolated trabeculodysgenesis, and goniotomy is the preferred initial procedure.

Skeletal dysplastic syndromes

This category embraces an enormous variety of systemic abnormalities with variable ocular manifestations that can include trabec-

ulodysgenic infantile glaucoma. Such disorders include Kniest syndrome,247,248,249,250 Michel syndrome,251 and the oculodento­

digital (ODD) syndrome.252 The latter syndrome, an autosomal

dominant disorder with phenotypic overlap with the HallermannStreiff and Meyer-Schwickerath syndromes,253,254 also manifests

with a variety of neurological findings.255

Corneodysgenesis

Axenfeld’s anomaly and Rieger’s anomaly and syndrome involve corneodysgenesis of the peripheral (Axenfeld’s) and midperipheral (Rieger’s) cornea and iris. These disorders appear to represent

a spectrum of developmental variations with genetic mutations in common,15b,175,256–259 rather than distinctive diseases.17,260 Despite

abnormalities in the cornea and/or iris in these syndromes, the trabecular meshwork in these disorders is histopathologically indistinguishable from that which is seen in primary congenital glaucoma.261

Axenfeld’s anomaly

Axenfeld’s anomaly (Figs 19-31 and 19-32) is characterized by a prominent anteriorly displaced Schwalbe’s line termed posterior embryotoxon. This finding differs from isolated posterior embryotoxon, which can be seen in normal eyes; in Axenfeld’s anomaly the bands of iris tissue extend across the anterior chamber angle and attach to a thickened Schwalbe’s line. Some patients have mild hypoplasia of the anterior iris stroma, but more severe defects of the iris are not present. The disease usually is bilateral, and the inheritance pattern is autosomal dominant.

Approximately 50% of patients with Axenfeld’s anomaly develop glaucoma. The glaucoma may occur in infancy and responds to goniotomy or trabeculotomy. If it occurs in later childhood, ­medical therapy should be tried initially, with trabeculotomy or trabeculectomy considered as surgical procedures.

Rieger’s anomaly and syndrome

Rieger’s anomaly (Figs 19-33 and 19-34A) may or may not have posterior embryotoxon with adherent iris strands, as in Axenfeld’s anomaly. However, midperipheral iris adhesions to the cornea are present in addition to significant iris abnormalities, which can include marked hypoplasia of the anterior iris stroma as well as

pupillary abnormalities, such as distortion of the pupil, polycoria, and corectopia.5 Occasionally the iris demonstrates hypolastic findings similar to the iridocorneal endothelial syndrome, but these conditions are rarely confused. Many differences in their clinical constellations – corneal specular microscopy, inheritance patterns,

laterality, etc. – distinguish the iridocorneal endothelial syndrome from the Axenfeld-Rieger’s syndromes.100,262,263 Progressive iris

thinning is most common following surgical intervention with peripheral anterior synechiae formation and can be seen in eyes with either Rieger’s or Axenfeld’s anomaly. The iris seems to be pulled toward the peripheral anterior synechiae, possibly because of contraction of endothelial cells that migrate across the peripheral anterior synechiae onto the exposed iris stroma (Fig. 19-35). Microcornea or macrocornea may also be evident. These ocular abnormalities are usually bilateral, and autosomal dominant transmission is the common inheritance pattern.

(B)

Fig. 19-34  (A) Patient had a large portion of iris absent in the upper temporal quadrant with wedge-shaped adhesion between the remaining iris and cornea. (B) The same patient with typical malformed and missing teeth as seen in Rieger’s syndrome.