Anencephaly is best diagnosed using :

Anencephaly is defined as absence of the cranial vault and is incompatible with life. Incidence: 1 in 1000 bihs Ultrasound is both a screening as well as diagnostic test for structural anomalies. In the first half of pregnancy, diagnosis is made by elevated levels of alpha-fetoproteins in amniotic fluid. It is CONFIRMED by USG. The findings around 10wks are: Absense of cranial vault Angoimatous brain tissue Anencephaly,encephalocoele and omphalocele are today being picked up on the first trimester scan. Iniencephaly: Failure of formation of cervical and upper thoracic veebrae and base of the skull with abnormally formed brain tissue. TEXT BOOK OF OBSTETRICS,Sheila Balakrishnan,2nd edition page no.487 Dc duuta's textbook of Obs,9th edition,page no.383