How reliable is an MRI at showing a head injury?
Is it possible for a head injury to get missed on an MRI?
Have you been in the emergency room recently to get checked out for trauma to your head?
“Some head injuries may show on MRI’s but it depends on the types of injuries,” says Yvette McQueen, MD, emergency medicine physician and CEO of MedQueen LLC, through which she offers travel medicine, urgent care and nutritional consultations via telemedicine to individuals, executives and travel groups.
“When someone presents to the emergency department (ED), an MRI is not the first test done,” says Dr. McQueen.
“Typically, we will order a CT scan of the head to determine the most immediate life threatening causes in a head injury.”
The quick identification of a serious head injury outweighs the radiation exposure from the scanner.
“A CT scan will reveal the bony structures and a break in the skull bones (skull fracture). It will also show us if there is an immediate bleed underneath the skull or within the brain.
“The bleeding is caused when blood vessels are broken during the injury. The density (brightness) of the blood and shape of the blood will tell us what type and time of the injury also.
“Immediate and fast bleeding is an epidural bleed or hematoma. The bleeding is lens shaped and presses against the brain, causes swelling of the brain.”
This is an acute brain injury; the resulting symptoms are swift and major.
“The person will have become unconscious, ‘knocked out’ or dazed, have a period of return awareness; but soon passes out again as the bleeding continues and pushes on the brain.”
Not all brain bleeds, though, occur immediately after the injury. Sometimes there is a delay.
“The slow bleed, subdural hematoma, conforms to the shape of the brain,” continues Dr. McQueen.
“Both of them will cause nausea, vomiting, confusion, sleepiness, changes in pupils, headache, dizziness, sometimes seizures. The CT scan is the most immediate way to determine a bleed within the skull or brain.”
The MRI and Head Injury miss
“MRI is typically used to evaluate the brain tissue for injury, bruising, contusion or disruption of the nerve cells,” says Dr. McQueen.
“If someone has prolonged symptoms of a contusion or concussion (bruising) of the brain, then an MRI is ordered and generally not from the ED.
“The concussion will cause nausea, vomiting, mild confusion, unable to get the thought processes together quickly, recent memory deficits.
“An MRI will determine if the nerve cells have been disrupted and not communicating with each other to process the actions.
“Like any bruise on your body, it takes time to heal and that’s why concussions may take 1-3 weeks to recover.
“They determine the severity of the concussion as mild, moderate or severe by a physical evaluation and actions we have the patient perform.
“The immediate danger is disability or worsening of the concussion due to reinjury of the same; the reasoning why players with concussion should not have contact sport for 1-3 weeks after a head injury.”
Dr. McQueen is an emergency physician and “The Travel Doctor.” She is a speaker, author and consultant, provides wilderness emergency care training, and international teaching for the American Heart Association.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.
.
