Anterior cleavage syndrome
Peters' anomaly showing the central leucoma
Anterior cleavage syndrome or mesenchymal dysgenesis is a group of disorders characterized by abnormal development
of the anterior segment especially at the irido-corneal angle. Glaucoma occurs in some of them. The three most common
types seen in the examination are:
There is a prominent irregular ridge which lies central to the limbus. This is a posterior embryotoxon caused by an anteriorly
displaced Schwalbe's ring. Note: this finding is seen in about 8 to 30% of normal individual. Look for another pathology as
it is unlikely that this sign alone will form the main finding in the examination.
There are bilateral posterior embryotoxon with iris strands attached to it. Peripheral anterior synechiae and hypoplasia of the
anterior stroma may be seen.
Note: recently Axenfeld's anomaly and Reiger's anomaly/syndrome have been re-classified as Axenfeld-Reiger's syndrome
because the two conditions have many overlapping features. However, some examiners may not be aware of this and may
ask you for the differences between Axenfeld's and Reiger's anomaly (Axenfeld's and Reiger's anomaly both have posterior embryotoxon plus anterior synechiae but only in Reiger's anomaly are there iris atrophy and pupil distortion; Reiger's
syndrome is Reiger's anomaly plus dental, craniofacial and skeletal abnormalities).
- corectopia, ectopia uvea and polycoria
- abnormal denture and maxillary hypoplasia
There are bilateral (80% being bilateral) central corneal opacities involving the stroma with iris adhesion at the edges of the
- small eye (microphthalmos)
- cleft lip/palate, craniofacial or skeletal abnormalities or evidence of congenital cardiac defects (if any of these were
- present, the condition is called Peters plus syndrome)
1. How are the above conditions inherited?