Banana and lemon sign is seen in which fetal anomalies:
Signs of Spina bifida on Ultrasound

Small biparietal diameter.
Ventriculomegaly.
Frontal bone scalloping or the so called lemon sign.
Elongation and downward displacement of the cerebellum-the so called banana sign.
Effacement or obliteration of the cisterna megna.
Neural tube defect
Hydrops fetalis
Twins
IUD