P015a: Prenatal ultrasonographic sequence ?Persistent Hyperplastic Primary Vitreous-retinal detachment? in a Walker Warburg syndrome

Abstract

Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterized by diffuse neurodysplasia, resulting in brain and eye abnormalities. We report on a prenatally diagnosed case of this syndrome born to a consanguineous couple. The patient was referred at 24 weeks following prenatal diagnosis of hydrocephalus at a 22 weeks routine scan. Major hydrocephalus was confirmed. In addition, abnormalities of the eye were found: an unilateral congenital cataract and a parasagital intra ocular structure in both eyes between the lens and the posterior wall of the eye. These structures were interpreted as bilateral hyperplasia of a persistent primary vitreous (PHPV). The parents elected to continue the pregnancy. Amniocentesis documented a normal male karyotype. MRI performed at 32 weeks confirmed hydrocephalus and lissencephaly II consistent with WWS, but was not contributive regarding the eye abnormalities. Ultrasonographic follow-up showed unchanged eye structures up to 34 weeks, when target like images suggestive of retinal detachment were found. The baby died immediately after birth. Autopsy showed dilated ventricles, thin cortex, type II lissencephaly and retinal dysplasia associated with retinal nonattachment, confirming the diagnosis of Walker-Warburg syndrome. The case we report demonstrates that prenatal sonographic diagnosis of retinal non attachment and of PHPV is feasible. It may have implications for prenatal diagnosis of conditions involving such abnormalities. Moreover, we report for the first time, on the prenatal occurrence of a retinal detachment following the presence of PHPV. It suggests that retinal dysplasia associated with WWS could be secondary to a retinal nonattachment due to PHPV, rather than resulting from a “primary” malformative process as classically accepted.