Iniencephaly with rachischisis fetal ultrasound by Dr. Amira shawky

Iniencephaly with rachischisis by Dr.Amira Shawky

The terminology “Iniencephaly” is derived from the Greek word “inion,” (meaning neck) and “encephalos,”(meaning brain). It describes the attachment of the posterior most part of the occipital bone to the back,resulting in the absence of the neck and retroflexion of the head ..Persistence of cervical lordosis in thethird week of pregnancy causes the neural tube not to close. Iniencephaly which is a neural tube defect consists of occipital bone defect in association with rachischisis of cervical and thoracic vertebrae..The neck is absent and the head is retroflexed with significant distortion in cervical and thoracic vertebrae..This neural tube defect is very rare but it is suggested that the incidence of iniencephaly is underestimated because of the misdiagnosis particularly when it occurs in association with complex malformations ..Iniencephaly is much more common in females than males and can be associated with many fetal malformations..Arthrogryposis is sometimes associated with iniencephaly .. According to the presence or absence of encephalocele; iniencephaly is divided into iniencephalus apertus (with encephalocele) and iniencephalus clausus (without encephalocele) …The list of associated malformations is large and includes CNS, GIT, chest, renal, cardiac, neuromuscular and skeletal anomalies ..The most important anomaly to be considered in the differential diagnosis of iniencephalus clauses is Klippel-Feil syndrome which results from malsegmentation of cervical vertebrae in the stage of early development however neither severe retroflexion of the head nor other spine deformities will be present in Klippel-Feil syndrome… The exact cause and pathogenesis of iniencephaly are not fully understood, but both genetics and environment may play a role. Environmental factors that increase the risk of iniencephaly are poor socioeconomic conditions, low parity, lack of folic acid supplementation, diabetes, obesity, and certain drugs. .. Chromosomal abnormalities such as trisomy 18, trisomy 13, and monosomy X have been detected accompanying this anomaly …Since iniencephaly has a recurrence rate of 1–5%, the women should be counseled for folic acid supplementation before future pregnancies. All women of reproductive age should be supplemented with 0.4mg (400mg) of folic acid daily to prevent neural tube defects. For a women who have previously had a fetus affected with neural tube abnormalities, the Center of Disease Control and Prevention (CDC), recommends increasing the intake of folic acid to 4mg per day beginning at least one month before conception …