Retrocerebellar arachnoid cyst

Objective 

To present a prenatally diagnosed case of retrocerebellar arachnoid cyst and discussion of management for this case.

Case 

A 24 years old, gravida 1, parity 0 pregnant woman was referred to our unit because of fetus with retrocerebellar arachnoid cyst at 22 weeks gestation. A detailed ultrasound scan was revealed a single live fetus with cranial retrocerebellar arachnoid cyst that is 28mm*22mm in diameter, cisterna magna that is 13.18mm in diameter and normal cerebellum(5th-50thh). After genetic counseling about the fetus prognosis; amniocentesis was performed. The result of fetal karyotype was 46 XX.

Conclusion 

Cystic anomalies are easily recognizable in the axial transcerebellar plane in the fetus. However, their differential diagnosis can be particularly diffucult. Retrocerebellar arachnoid cyst is a cerebrospinal fluıd collection and sonographically it appears as a sonolucent cystic mass. Retrocerebellar arachnoid cyst can be diagnosed by prenatal sonography into second trimester, but it should be distinquished from mega cisterna magna, Blake's pouch cyst, Dandy-Walker malformation

Keywords

Retrocerebellar arachnoid cyst, prenatal diagnosis

	File/Dsecription
	Figure 1 Retrocerebellar cyst
	Figure 2 Cisterna magna