The cranium is that part of the skull which encloses the brain. Sometimes fetal abnormalities with the cranium require a cranial echogram. It is also known as fetal cranial sonography. An echogram produces an image of an object or organ of the body. The image is created by reflecting high-frequency sound waves to produce an ultra-sonogram, also known as an echogram. It is used to monitor fetal growth or study other organs of the body.
Fetal cranial echogram has been used to detect ventriculomegaly. This requires additional imaging techniques to provide accurate prognosis of structural abnormalities, such as a maternal magnetic resonance imaging (MRI). Imaging can be done at 17 to 39 weeks using a spin-echo. This is a multislice technique that uses intramuscular morphine to sedate the fetus. An MRI clarifies the results of the sonography. However, MRIs can sometimes fail to detect cases of lumbar meningomyelocele linked with the Chiari II malformation. Best results for fetal echograms are obtained during the third trimester of the pregnancy. MRIs act as a good adjunct to fetal cranial echograms as they help delineate abnormalities of the fetal central nervous system.
A cranial echogram for fetal distress can help determine the cause of fetal distress. Using a cranial echogram is a reliable way of diagnosing the problem before any radical treatment can be given. Some of the causes of fetal distress are as follows: breathing problems, position of the fetus, multiple fetuses, umbilical cord prolapse, shoulder dystocia, placenta abruptions, nuchal cord problems, or premature closing of the fetal ductus arteriosus. In numerous situations, fetal distress leads obstetricians to immediately deliver the baby either by inducing labor or through a caesarean section. A cranial echogram for low birth weight can also be used to determine the condition of premature babies. Such babies are prone to develop learning difficulties, eyesight problems, cerebral palsy, and chronic respiratory problems such as asthma. Prematurely born babies also stand the risk of developing intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL). IVH is also known as bleeding in the brain; this condition is easily detected in the first week of birth through imaging technology such as cranial ultrasound. PVL, occurs when there is damage to the brain tissue because of less oxygen or blood flow. PVL may take longer to detect and may require repeat ultrasound tests to be conducted starting from the fourth week of birth to the eight week after birth.