Demystifying Posterior Cranial Fossa Lesions in the Fetus

Abstract

Posterior fossa lesions are rare. Introduction of high resolution ultrasound with 3D reconstruction and endovaginal evaluation of fetal brain through the fontanelle helps in better understanding of neuroanatomy. MRI is often used as an additional tool for evaluation in addition to ultrasound studies. Major components of posterior fossa such as cerebellar hemispheres, vermis, fourth ventricle, cisterna magna, and their normal variants and abnormalities can be demystified by ultrasound studies. Morphometry of these structures helps in the diagnoses of these abnormalities.

Counseling for Fetal Central Nervous System Defects

“…Diagnostic pitfalls for posterior fossa lesions: Antenatal sonography may not always delineate the exact lesion and fetal MRI is often needed for adjunct imaging [33].…”