Radiology Services

Newspaper Column

Question: My wife and I were in a wreck last week. We went to the ER by ambulance. They took her to Radiology for a CT scan of her head. They just did an x-ray of my knee. Why didn’t they get a scan of my head too?

Answer: Each patient involved in a traumatic accident is first clinically evaluated by a physician to determine whether there is injury of a severity that requires more testing.

In your case, unless you had evidence of trauma to your head, or you had symptoms of loss of consciousness or other symptoms related to your head or nervous system, no brain CT would have been indicated.

In the “old days” patients who sustained head injuries would only be evaluated by an x-ray study for a skull fracture. Anything short of a skull fracture was just observed for any neurologic symptoms that might indicate an injury that might not be shown on a skull x-ray.

A skull fracture shown on an x-ray could be a sign of enough trauma to break a blood vessel running in the inner lining of the skull to cause a hemorrhage that might be life threatening. If the fracture was in the area of the temple, a very dangerous artery runs there, and that artery is famous for causing fatal hemorrhage in a short period of time if not discovered and treated surgically.

If the bleeding from the head injury causes no internal bleeding from the high-pressure artery, there is still danger from low pressure bleeding from veins covering the brain. Often, those vein injuries initially cause only short-term local pain, but later cause neurologic symptoms, headache, weakness and sometimes, stroke-like symptoms.

Before the availability of Computerized Tomography (CT), emergency arteriograms had to be performed to determine the presence or absence of such injuries. Arteriograms are done by placing a tiny tube (catheter) in the large artery in the groin, and manipulating the catheter up through the abdomen and the chest to inject dye into the blood vessel supplying the brain. This is a very complicated procedure, and not without risk in itself.

Sometimes, the arteriograms just showed swelling of the brain without bleeding from an artery or vein. Bleeding from an artery would show a blood collection shaped like a tiny football, while bleeding from the vein would be shaped like a crescent moon. If the blood collection looked like it came from an artery, emergency surgery was done immediately. Bleeding from a vein was still serious, but could be observed for resolution without surgery, or treated by non-emergent drainage.

Today, we have sophisticated methods of more immediate diagnosis by means of the CT scan. This emergency scan procedure determines the presence of brain swelling, hemorrhage at the surface of the brain from bleeding arteries or veins, and can identify internal brain hemorrhage from certain kinds of strokes. Only extremely rarely do we need to do arteriograms for emergency cases.

Your own injury indicated only the need for a simple knee x-ray, so you should feel fortunate the extent of your injuries was not so severe as your wife’s. If there are continued symptoms at your knee, MRI scanning may be needed for discovery of internal damage to your knee to ligaments or cartilage. Follow-up with your doctor to determine whether that is required.

During the upcoming Christmas and New Year’s celebrations, I wish everyone the Merriest of Christmas seasons, and the Happiest of New Years. Make sure you have designated drivers so you can avoid any personal experiences with the modern miracles of diagnostics we have talked about in today’s column.