Nurse Mariane is caring for an infant with spina bifida. Which technique is most important in recognizing possible hydrocephalus?
A. Obtaining skull X-ray
B. Measuring head circumference
C. Performing a lumbar puncture
D. Magnetic resonance imaging (MRI)
Correct Answer: B. Measuring head circumference
Measuring head circumference is the most important assessment technique for recognizing possible hydrocephalus, and is a key part of routine infant screening. Congenital hydrocephalus is usually present at birth. An unusually large head is a significant sign of congenital hydrocephalus.
Option A: X-rays of the skull may show erosion of sella turcica, or so-called “beaten copper cranium” appearance, but are seldom helpful or indicated with the availability of better imaging techniques. Ultrasonography through anterior fontanelle may be used in infants for evaluating the ventricular system and progression of hydrocephalus.
Option C: A lumbar puncture isn’t appropriate. CSF analysis could be done to help with the diagnosis and to exclude residual infection. Neuroimaging plays a central role in confirming the diagnosis in suspected cases, identifying the cause and possible treatment. In cases of acute hydrocephalus, an emergency head computed tomographic (CT) scan is the first option to assess the ventricular size.
Option D: MRI may be used to confirm the diagnosis. Magnetic resonance imaging (MRI) of the brain is the study of choice as it shows better the posterior fossa structures, can differentiate between brain tumors and degenerative diseases and can differentiate NPH from cerebral atrophy.