The Miami Marlins receive quite a scare on Sunday when Derek Dietrich was hit by a stray foul ball off the bat of Christian Yelich during a game in which he was excelling. Dietrich was hit in the back of the head via ricochet, as the foul ball hit the back of the dugout before clipping him.
There were major concerns about Dietrich despite the fact that he seemed all right directly after the injury. He stayed overnight in Atlanta after the Marlins' win and received testing for the injury. It looks like everything has been cleared, however, and Dietrich was available to hit last night if needed in the team's eventual 10-0 loss to the Pittsburgh Pirates.
"I was cleared of any type of concussion," Dietrich said. "I passed all the tests last night. That was the big thing they were looking for, obviously, and if it had broken the skin or [if there was] any kind of fracture.
"All the tests were good. X-rays were negative. CT scan was clear. So everything was good."
This is the kind of stuff I deal with on a daily basis in the emergency department. Head injuries are a common complaint, ranging in etiology anywhere from being hit by a fast object to simply falling down and hitting their head. The level of workup, of course, is entirely dependent on the story that the patient tells and what the patient looks like when first seen. The reason why this is important is because, depending on the patient's age and risk, radiation can do more harm than good.
In a patient like Dietrich, a good history and physical examination would first be performed. As he begins the story, I already have to note several factors that will help me make a determination as to whether he needs imaging. These factors are often in a research study-verified list of symptoms and other concerning historical pieces. For example, the following are the factors that I would consider using if I used the NEXUS II head CT rules, first published in a 2002 paper by Mower et al.
Age ≥ 65yr
Evidence of significant Skull Fracture
Recurrent or forceful vomiting
The American College of Emergency Physicians has a consensus policy that considers scanning in certain instances, depending on whether a patient lost consciousness or not.
A noncontrast head CT indicate in head trauma patients with LOC or post-traumatic amnesia only if 1 or more of following is present:
Age greater than 60
Drug or alcohol intoxication
Deficits in short-term memory
Physical evidence of trauma above the clavicle
GCS less than 15
Focal neurological deficit
A noncontrast head CT should be considered in head trauma patients with no LOC or post-traumatic amnesia if there is:
Focal neurological deficit
Age 65 or more
Physical signs of basilar skull fracture
GCS less than 15
Dangerous mechanism of injury
The common questions I ask are about persistent vomiting, vision changes, weakness in an arm or a leg, whether a patient passed out, whether they are acting differently or funny as per their family/friends with them, and whether they take any blood thinning medications for other medical conditions like warfarin for certain heart problems. Using this information and the guidelines above, I can decide if a patient needs to be scanned.
You might ask why not scan everyone who sounds like they might have a concerning story. Dietrich got hit in the head with a flying weapon, should that not be enough to buy him imaging? Well, not exactly. If he had no symptoms afterward and no signs of a gross injury on examination, not every person hit in the head with an object necessarily needs scanning. This is good because not only does it save the emergency department time and the patient (presumably) money, but it saves them dangerous radiation that could hurt them in the long run. CT scans of the head are relatively benign compared to harder-hitting scans like chest studies, but they still carry a good amount radiation risk. The younger you are, the more time that radiation has to eventually potentially develop cancerous changes.
Just how much is that? The website X-ray Risk provides estimates for additional risk to baseline for cancerous development over a lifetime. For a 26-year-old like Derek Dietrich, the addition of one CT scan is only adding an additional 1-in-5110 risk. Given that the mechanism of his injury did seem dangerous and, more importantly, that the team was concerned enough to send him to an ER presumably, imaging was probably an easy group decision.
I do find it interesting that the team opted for both "X-rays" and a CT scan, as Dietrich notes in his article quote. Perhaps the team also got cervical spine X-rays to rule out a break there. Skull X-rays are almost entirely out of favor now due to the prominence of CT head imaging being available.
From there, Dietrich went on to basic concussion testing and seemingly passed all the tests, which makes me wonder if he really needed imaging at all or whether this is more of a policy that the team went about. Dietrich seemed to be all smiles when he eventually returned to Miami, though Miami took extra precautions with him.
Likely the Marlins followed a team policy after head injury rather than any particular clinical guideline, but it seemed like everything tested out well. No lasting signs of concussion is a good thing, and Dietrich should be getting back on the field shortly, perhaps as soon as tonight against the Pirates.