Spontaneous cervical artery dissection is likely a misnomer, as only 20 to 35% of these patients truly have no mechanical event reported. Traumatic dissections occur with large trauma such as hanging, MVC, etc, but mechanical triggers such as sneezing, chiropractic neck manipulation, sex, yoga, etc are the predisposing events in spontaneous cervical artery dissections. You should think of this diagnosis in young patients with stroke, as cervical artery dissection is to blame in 20% of ischemic strokes in young people.
Your index of suspicion should be increased when a patient has neck pain, headache, or evidence of ischemic stroke with history of a connective tissue disease. Carotid dissections are more common than vertebral artery dissections. Any motion with hyperextension and torsion will stretch the carotid artery and compress it against C2 or C3. Dissections are usually extracranial, although some reports indicate that intracranial dissections are more common in Asian populations. Headache is present in the majority of carotid and vertebral artery dissections. Anterior neck pain is present in nearly all carotid dissections but usually not present in vertebral dissections. Similarly, posterior neck pain is present in almost all vertebral dissections but usually not present in carotid dissections.
Stroke is found in 67-73% of patients with cervical artery dissections, with TIA present in 23% of spontaneous dissections and up to 85% of traumatic dissections. The average age of a patient with stroke from spontaneous cervical artery dissection is only 45 years old! The exact findings on neuro exam will vary depending on the vessel affected. Interestingly, 20 to 48% of patients with carotid artery dissection will have Horner syndrome (ptosis, miosis, and anhydrosis).
The gold standard for imaging is four vessel angiography, but the availability of this is limited at many centers. Also, most of us do not like sending our patients out of the department for long periods of time when a diagnosis such as cervical artery dissection is in the differential. The tests of choice are CTA and MRA, although many studies have shown similar efficacy. CTA has a sensitivity of approximately 90%. Angiography is usually reserved for patients with a negative CTA or MRA and the diagnosis is still suspected.
The treatment for spontaneous cervical artery dissections with symptoms of acute stroke is primarily with tPA. The efficacy of tPA is slightly lower than in patients with ischemic strokes not associated with a dissection. A recent meta-analysis showed that the risk of intracranial hemorrhage is the same while using tPA in patients with dissection/stroke compared to non-dissection ischemic stroke. Do not use tPA if the dissection is intracranial or if the aorta is involved. Also, you still need to use the contraindication list for using tPA. If there are symptoms of ischemic stroke present in the cervical arterial dissection patient, anticoagulation or antiplatelet therapy is indicated. Also, you can use antiplatelet therapy 24 hours after tPA is given for patients with dissection and stroke. No randomized controlled trials exist for anticoagulation vs antiplatelets in these patients but a meta-analysis showed similar efficacy. Endovascular therapy is usually reserved for recurrent dissections or those that fail conservative treatment.
Liebeskind D, Saver J. Spontaneous cerebral and cervical artery dissection: Treatment and prognosis. Uptodate.com. Updated April 18, 2012.
Liebeskind D, Saver J. Spontaneous cerebral and cervical artery dissection: Clinical features and diagnosis. Uptodate.com. Updated June 8, 2012.
Shea K, Stahmer S. Carotid and verterbral arterial dissections in the Emergency Department. Emergency Medicine Practice. April 2012. 14(4):1-24.