Anencephaly

ANENCEPHALY

1. Dr Arun Gupta Director imaging Dr Rakhee gupta Dr R K S Gandhi Dr Vinayak Mittal Dr Ritesh Mahajan ANENCEPHALY

2. ANENCEPHALY CHARACTERIZED BY Absence of the Cranial vault Cerebral hemispheres Diencephalic Structures. These structures are replaced by a flattened, amorphous Vascular-neural mass Area Cerebro-vasculosa Coronal view of fetus shows the spine ending in a clump of amorphous vascular neural mass without a formed cranial vault .

3. TUI Tomographic USG imaging Appreciate the spine ending in the skull base bones . No cranial vault bones . Amorphous vascular neural mass appreciated over the skull base

4. Rendered image of the fetal orbits with absence of the normal Formed cranial bones . Fetal orbits Absence of the Cranial vault bones Area cerebro vasculosa

5. An overview ………………….. Area cerebrovasculoa may resemble brain but there is always absence of the skin , cranial bones and brain above the orbits. Facial structures and orbits are present . Spine , Non CNS anomalies , Polyhydramnios are usually associated . Dysraphism may involve entire head/ spine ( Craniorachischisis ) Outcome of the anencephaly is invariably fatal and termination is offered at any age . Eraly detection ( as early as 14wks ) . TVS examination with dedicated assessment of the frontal bones can be attempted for early detection but diagnosis of anencephaly should not be made before 10wks of gestation. ANENCEPHALY

6. In early pregnancy area cerebro-vasculosa may resemble normal brain without bony covering ( exencephaly ) but as the pregnancy grows the brain is destroyed and becomes flattened as in anencephaly . ANENCEPHALY An overview …………………..

7. CORONAL VIEW Fetal orbits appreciated . Appreciate flattening of the curvature above the fetal orbits

8. FORMED BASAL SKULL BONES POLYHYDRAMNIOS APPRECIATE THE Echogenic amniotic fluid caused by debris shed from the uncovered brain .

9. Anencephaly : absence of the cranial vault, cerebral hemispheres, and diencephalic structures. These are replaced by a flattened, amorphous vascular-neural mass (area cerebrovasculosa ) Exencephaly : normal brian uncovered by bone Craniorachischisis: dysraphic abnormality involves the head and entire spine Acrania : absence of the cranial vault bones of the calvarium TERMINOLOGY

10. REFERENCE DIAGNOSTIC ULTRASOUND FOURTH EDITION Carol M. Rumack , MD, FACR J. William Charboneau , MD, FACR Deborah Levine, MD, FACR