Ultrasound imaging of the cranium, also known as cranial or head ultrasound, produces images of the brain and the cerebrospinal fluid that flows and is contained within its ventricles. Ventricles are the fluid-filled cavities located in the deep portion of the brain.

Ultrasound imaging uses a small probe, called a transducer, and gel placed directly on the skin. High-frequency sound waves travel from the probe, through the gel, into the body. The probe collects the sounds that bounce back. A computer uses those sound waves to create the images for the exam.

Ultrasound is painless and non-invasive.

When would I get an Ultrasound of the Cranium?

Since ultrasound waves do not pass through bone easily, this exam is most commonly performed on infants, whose skulls have not completely formed.

The gaps between those skull bones provide a “window,” allowing the ultrasound beam to freely pass into and back from the brain. The ultrasound probe and some gel are placed on the outside of the head in one of those regions without bone.

In adults, head ultrasound is used to locate and evaluate tumor masses during brain surgery, facilitating their safe removal.

What Will I Experience?

The infant will lie on their back on an exam table. Their position may be adjusted to either side in order to improve the quality of the images captured during the exam.

An ultrasound technologist will apply a warm water-based gel to the head. The gel will help the transducer make secure contact and eliminate air pockets between the transducer and the skin that can block the sound waves from passing into their body. The transducer is placed on the head and moved back and forth over the area of interest until the desired images are captured.

There is usually no discomfort from pressure as the transducer is pressed against the area being examined. 

Once the imaging is complete, the clear ultrasound gel will be wiped off their head. Any portions that are not wiped off will dry quickly. The ultrasound gel does not usually stain or discolor clothing.

Typically, ultrasound imaging of the cranium takes approximately 15 to 30 minutes to complete.