Detailed sonographic mappings of normal fetal brain anatomy in utero at six levels in the axial plain.

An investigation of real time sonographic features of the normal fetal brain at six levels in the axial plain was undertaken between the 26th and 40th week of gestation. Structures such as cerebrum, midbrain, basal ganglia, ventricular system, vascular system, and cerebellum can be routinely identified if ultrasound is performed systematically. The sonographic appearance of detailed brain anatomy at each level is presented with the hope that it may provide a systematic form of scanning the fetal brain. With such standardization of technique many erroneous interpretations may possibly be avoided.