For enthusiasts, the first snowfall means the start of the winter sports season. But for radiologists, the winter months mean an inevitable increase in brain, spine, and head and neck injuries.
"Winter sports are very popular, especially in Europe and the U.S.," said Mariana Dalaqua, MD, deputy head neuroradiologist at Valais Hospital in Sion, Switzerland. "Although they are a lot of fun, they also cause a high number of injuries."
In fact, every year in the U.S. around 200,000 skiers and snowboarders find themselves in the emergency room (ER) with nearly 7,000 people requiring hospitalization. Of these, between 3 – 15% are head and neck injuries and 1 – 13% are spinal injuries.
"Despite accounting for only a small fraction of injuries overall, neurologic injuries are the leading cause of death and disability in skiers and snowboarders," said Dr. Dalaqua, who discussed the main CT and MRI aspects of severe winter sports related injuries during a Saturday session.
CT or MRI?
A skier or snowboarder admitted to the ER for head or spinal trauma requires fast assessment. That is why Dr. Dalaqua recommends using CT over MRI.
"Not only is CT more readily available than MRI, CT can also clearly depict facial and skull fractures, as well as extra-axial hemorrhage in head trauma," Dr. Dalaqua said. "Brain contusions can also be readily characterized, especially the hemorrhagic ones."
Although CT is one test used to categorize a brain injury, Dr. Dalaqua warns that initial findings representing diffuse axonal injury can be subtle.
"Cases of high-kinetic energy trauma with normal CT and clinical-radiological dissociation should be further investigated with MRI," she added.
Even in the absence of a skull or cervical fracture, Dr. Dalaqua says that radiologists should be suspicious of a possible vascular injury.
"Hyperflexion, hyperextension, acceleration or deceleration are all red flags requiring a more comprehensive investigation," she said. "If the patient presents any of these mechanisms, or a skull base or cervical fracture of the vertebral foramina, then a CT angiography is preferred over an MR angiography to start."
As far as spinal cord injuries, CT will highlight fractures and dislocations in the spine, but MRI offers superior sensitivity for subtle fractures, soft tissue lesions, spinal canal hemorrhage and spinal cord injuries.
However, because peripheral nerve trauma is often associated with orthopedic trauma, CT is the modality of choice (although MRI of the brachial or lumbo-sacral plexus is usually required to get a direct visualization of the peripheral nerve injury).
"By understanding the mechanisms of the injury and the risk factors involved, radiologists can play a big part in reducing the severity of winter sports-related injuries," Dr. Dalaqua concluded.
For More Information:
View the session, Winter Sports Trauma: What a Radiologist Should Know About Brain, Spine and Head and Neck Injuries in Snow — NR125-ED-X at RSNA2020.RSNA.org.