2012-07-18-10 Blake's pouch cyst ©Elena Andreeva www.TheFetus.net
Blake's pouch cyst
Elena Andreeva, MD; Natalia Odegova, MD
Moscow regions Research Institute of Obstetrics and Gynecology, Medical-Genetics Department, Moscow, Russia.
A 25-year-old G1 P0 with non-contributive family and personal history was referred to our center at 24 weeks and 30 weeks of gestation. We found Blake’s pouch cyst. No other abnormalities were detected.
The baby boy was born at term, weight of 3500 gr, height of 53 cm, Apgar 7/9 with no neurological symptoms. At the age of 3 months, MRI was performed and confirmed the diagnosis. The child develops without neurological disease.
Blake's pouch cyst (BPC) has been considered a pathological entity deriving from abnormal development of the posterior membranous area of the fetal brain. This pathology is characterized by normal anatomy and size of the vermis; mild/moderate anti-clockwise rotation of the vermis; normal size of the cisterna magna.
Image 1: 24 weeks. Normal profile of fetus
Image 2: 24 weeks. Normal appearance of cerebellum in the upper part
Image 9: (1)mid brain with pons (brain stem); (2)Vermis; (3)oriented line for assessing the topography of the vermis; (4)cavum vergae (continuation of cavum septum pellucidum); (5)Corpus callosum; (6) arrow showing inferior medullary vellum. Large gap between the inferior vermis and brain stem.
Image 10, 11: 3D reconstruction scan showing the position of the Blake's pouch cyst
Image 12, 13: The normal brain structure (left) and the elevation of the cerebellum when the Blake's pouch cyst exists(right) enlarging the posterior fossa.