The success rate, which relies on strict amblyopia therapy and requires prolonged follow-up, varies but is better with isolated unilateral cases. Recorded attempts to treat Peters anomaly involve keratoplasty. Various chromosomal abnormalities have also been associated with Peters anomaly among them trisomy 13-15, ring chromosome 21, Norrie disease, partial deletion of chromosome 11 q, mosaic trisomy 9 and the 49XXXXY syndrome ( see Table 1). Among the systemic associations occurring with Peters anomaly are congenital heart disease, neurologic defects, genitourinary abnormalities, external ear abnormalities and cleft lip and palate. However, both types of Peters anomaly may be either unilateral or bilateral. More cases tend to occur bilaterally and these are more prone to have systemic associations. A study by Bhandari et al., for instance, showed equal distribution in both sexes. The few published studies do not show any gender predilection for Peters anomaly. The critical step in the development of Peters anomaly occurs in the first trimester during the formation of the anterior chamber. The etiology of Peters anomaly is not known and environmental as well as genetic factors are thought to play a role in its genesis. This type is also associated with more systemic and ocular malformations. Thus, some cases of Type II Peters anomaly, which often tends to occur bilaterally, may be associated with PAX6 gene mutations. Normally mutations in the PAX6 gene are associated with defects in the development of ocular tissues.
The lens in this type also adheres to the cornea. Type II is usually associated with a cataractous lens. In the type I anomaly, the lens may or may not be cataractous and does not adhere to the cornea. Type I which occurs in the majority of the cases and type II which occurs less often. Two forms of Peters anomaly are recognized. In Peters anomaly, the corneal opacity is either central or paracentral and it usually does not exhibit vascularization. It is important to differentiate Peters anomaly from other causes of corneal opacification. Other causes of congenital corneal opacification include sclerocornea, tears in the Descemet membrane secondary to birth trauma, ulcers, congenital glaucoma, congenital hereditary endothelial damage and various metabolic derangements. It is among the causes of congenital clouding and/or opacification of the cornea. Inherited cases are either autosomal dominant or recessive. Peters anomaly is a developmental disorder of the cornea which can occur either sporadically (in most of the cases) or be inherited in a few cases. The anterior chambers appeared normal with no strands between the cornea and the iris or lens. The opacities were totally homogeneous with no blood vessels visible. On examination the baby was noted to have bilateral corneal opacities which were completely covering the iris and pupils (see Figures 1 and 2). Also noted in the cesarean section room was the presence of extra digits and club foot.Īs a normal procedure, the baby was received at our newborn unit for stabilization and observation while the mother recuperated from anesthesia. The neonate was noted to have clouded cornea. There was no family history of any congenital anomalies. The elder sibling was delivered vaginally and did not have any anomalies. The mother had only received iron supplements during pregnancy and did not have an obstetric ultrasound done. A Kenyan baby girl of African descent was delivered at term through an emergency caesarean section due to fetal distress (meconium stained liquor grade II with mild uterine contractions at cervical dilatation of 7 cm.).
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