Family Nurse Practitioner Exam

What is the first imaging test recommended for infants with signs of occult spina bifida?

1. An ultrasound of the sacrum

2. A CT scan of the spine

3. A plain radiograph of the lumbar spine

4. Magnetic resonance imaging (MRI)

The correct answer is: An ultrasound of the sacrum

An ultrasound of the sacrum is the first imaging test recommended for infants with signs of occult spina bifida. This preference is based on several factors. Ultrasound is a non-invasive procedure that can be performed quickly and does not involve radiation, making it especially suitable for infants. It can effectively identify abnormalities in the spinal area, such as defects or cysts associated with spina bifida, and it allows for visualization of related structures without the need for sedation, which is often required for other imaging modalities. In contrast, while CT scans and MRIs provide detailed images of the spine and can reveal complex abnormalities, they involve higher levels of radiation exposure and are typically more expensive. Furthermore, CT scans are less commonly used in pediatric patients due to the associated risks and the need for sedation. MRI, although highly informative, is usually considered after initial ultrasound findings or if there is a need for more detailed assessment, particularly when the ultrasound has raised concerns. A plain radiograph might not provide the specificity needed to diagnose conditions related to spina bifida, as it generally can show the bony structures but lacks the capability to evaluate soft tissues and neural structures adequately. Thus, ultrasound stands out as the best choice for initial assessment in this context.