The following picture shows the lumbar meningo myelocele.
the following images are 3 d reconstruction.
the conventional markers are not very helpful – lemon sign not made out
banana sign is not so clear; but cerebellar shape is changed – boomerang
BPD and HC less than 2.3%tile is a subtle marker to look at the spine closely
This again illustrates the need to pick up open neural tubal defects earlier , when the lemon and banana sign are much easier to appreciate .
Appreciation of internal translucency in the 1st trimester needs a learning curve , in which all obstetrics practicing sonologists should invest .
Microcephaly could be an important marker in the late 2nd and 3rd trimester scans.