Diagnostic distinction between anencephaly and amnion rupture sequence based on skeletal analysis

Area of Science:

• Embryology
• Developmental Biology
• Medical Imaging

Background:

• Amnion rupture sequence (ARS) can cause severe fetal malformations.
• Distinguishing primary developmental defects from secondary effects of ARS is crucial for diagnosis and counseling.
• Anencephaly is a severe neural tube defect characterized by the absence of a major portion of the brain, skull, and scalp.

Purpose of the Study:

• To investigate axial skeletal malformations in fetuses with ARS and cranial involvement.
• To determine if radiographic analysis of the axial skeleton can differentiate between primary anencephaly and secondary ARS.
• To assess the utility of skeletal malformations in genetic counseling.

Main Methods:

• Radiographic and histological examination of the axial skeleton in eight second-trimester fetuses diagnosed with ARS and cranial involvement.
• Detailed analysis of vertebral bodies and craniofacial skeletal components.
• Comparison of findings with known patterns of anencephaly.

Main Results:

• Three of eight fetuses exhibited axial skeletal malformations consistent with anencephaly, including vertebral body malformations (double corpora) and cranial base abnormalities.
• These malformations were located along the notochordal path.
• Radiographic assessment of the axial skeleton proved effective in distinguishing between fetuses with primary anencephaly and those with secondary ARS.

Conclusions:

• Axial skeletal malformations, particularly those along the notochordal course, are indicative of primary developmental defects like anencephaly.
• Radiography of the axial skeleton is a valuable tool for differentiating primary anencephaly from secondary ARS.
• This imaging method enhances fetal examination and provides critical information for genetic counseling.