Case Study: Headache, neck stiffness, and fever
The image shows a case of Horner syndrome. When the patient was asked if he had recently injured his neck or had been to a chiropractor, he stated that he recently had his neck manipulated by a chiropractor. What you should do next is order a CT-angio of the neck. See the images below, with an arrow pointing to the left internal carotid artery dissection.
Left internal carotid artery (ICA) dissection (cut #1)
The arrow points to septum with blood in both lumens. Note how the left ICA is dilated compared with the right. This stretches the sympathetic nerves running outside the artery, thereby causing Horner syndrome.
Left ICA dissection (cut #2)
On this cut, there is only blood in the true lumen with the false lumen clotted. Because of this, the ICA looks smaller on the left than the normal right.
Carotid artery dissection is a rare but important diagnosis because it can lead to stroke. It only causes about 2% of strokes overall, but it causes about 20% of strokes in younger patients. The goal is to make the diagnosis prior to stroke if possible, but this is obviously more difficult because the physical exam will usually still be normal unless Horner syndrome is present. Carotid dissection should be considered whenever there is severe unilateral head, face, or neck pain that is not consistent with prior headaches or other more common conditions, and it must be considered if there are also symptoms or signs consistent with TIA or stroke or when Horner syndrome is noted. As one would expect, the pain in carotid dissection is usually unilateral, but contrary to what one might expect, it usually comes on gradually. About 20% of cases present atypically, with pain occurring bilaterally, as in this case. The pain can closely mimic a migraine without aura. There are a number of known risk factors for carotid dissection, but most patients have no known risk factors at the time of diagnosis.
The diagnosis of carotid dissection is best confirmed by CT or MR angiography of the neck. Carotid duplex is almost as sensitive and can be considered as well, although it should not be used if vertebral artery dissection is suspected due to lower sensitivity. Treatment for carotid dissection is usually with heparin followed by warfarin, but aspirin alone may be as effective. Patients should be admitted to the hospital with a neurology consult.
Brady Pregerson, MD, is an emergency physician at Cedars-Sinai Medical Center in Los Angeles and at Tri-City Medical Center in Oceanside, California.
Pregerson B. Emergency Medicine1-Minute Consult Pocketbook. 5th ed. EMresource.org; 2017.