A 30-year-old man comes to the emergency department due to severe headache and neck pain following a motor vehicle collision. The patient has no blurry or double vision, dizziness, slurred speech, numbness, or weakness. Neuroimaging is unremarkable except for evidence of a right transverse foramina fracture at the level of C2. The patient is placed in a cervical collar and admitted to the hospital. While undergoing further evaluation, he suddenly develops dizziness, right-sided facial numbness, and hoarseness. Temperature is 36.7 C (98.1 F), blood pressure is 160/90 mm Hg, pulse is 80/min, and respirations are 12/min. Neurologic examination shows partial ptosis and miosis of the right eye, as well as nystagmus. Hearing is intact bilaterally. There is reduced sensation to pain and temperature on the right side of the face and the left side of the body. The patient is ataxic and displays past-pointing with his right hand on finger-to-nose testing. Vascular imaging will most likely reveal an acute dissection in which of the following arteries?

Question

A 30-year-old man comes to the emergency department due to severe headache and neck pain following a motor vehicle collision.  The patient has no blurry or double vision, dizziness, slurred speech, numbness, or weakness.  Neuroimaging is unremarkable except for evidence of a right transverse foramina fracture at the level of C2.  The patient is placed in a cervical collar and admitted to the hospital.  While undergoing further evaluation, he suddenly develops dizziness, right-sided facial numbness, and hoarseness.  Temperature is 36.7 C (98.1 F), blood pressure is 160/90 mm Hg, pulse is 80/min, and respirations are 12/min.  Neurologic examination shows partial ptosis and miosis of the right eye, as well as nystagmus.  Hearing is intact bilaterally.  There is reduced sensation to pain and temperature on the right side of the face and the left side of the body.  The patient is ataxic and displays past-pointing with his right hand on finger-to-nose testing.  Vascular imaging will most likely reveal an acute dissection in which of the following arteries?

Quizplus · Accepted Answer

11ec160b_35b7_9e27_9249_616cae8fa58c_MD0001_00 After sustaining cervical neck trauma, this patient had a stroke that resulted in lower cranial nerve nuclei deficits (eg, vertigo, hoarseness) and loss of pain and temperature sensation on the right side of the face (trigeminal nucleus) and left side of the body (spinothalamic tract). Because most cranial nerves (other than CN II & IV) do not decussate while most of the body's motor and sensory fibers cross the midline in the medulla, brainstem strokes characteristically lead to ipsilateral cranial nerve deficits and contralateral deficits of the body (ie, crossed signs). Specifically, this patient has the following: Vertigo without hearing loss, suggesting a lesion impacting the vestibular nucleus rather than the peripheral CN VIII (which would likely result in hearing loss as well). Loss of pain/temperature sensation on the right (ipsilateral) side of the face, suggesting involvement of the spinal trigeminal nucleus Loss of sensation on the left (contralateral) side of the body, suggesting dysfunction of the spinothalamic tract Unilateral ataxia of the upper limb, suggesting a lesion affecting the cerebellum or inferior cerebellar peduncle Hoarseness, which is likely due to a deficit of the vagal nerve (CN X) or its nucleus (nucleus ambiguus) Horner syndrome due to damage of descending sympathetic nervous system fibers that travel near the spinothalamic tract This combination localizes to the lateral medulla. Lateral medullary (Wallenberg) syndrome is most commonly caused by occlusion of the vertebral artery or one of its branches. Cervical spine trauma can cause dissection of extracranial vessels (eg, carotid, vertebral arteries), causing ischemic stroke in young patients. (Choice A) The bilateral vertebral arteries join at the junction between the medulla and pons, forming the basilar artery. Strokes due to basilar artery occlusion typically impact the pons, not the medulla. (Choices B and C) Common and internal carotid artery dissections can occur with cervical spinal injuries. Carotid artery occlusion typically causes profound neurologic deficits (eg, contralateral homonymous hemianopia, hemiparesis, hemisensory loss) due to infarction of large portions of the cerebral hemisphere. (Choices D and E) Traumatic dissections involving the intracranial arteries are rare. Middle cerebral artery occlusion causes contralateral hemiparesis and hemisensory loss (face and arm > leg), conjugate gaze deviation, contralateral homonymous hemianopia, and aphasia (dominant hemisphere). Posterior cerebral artery occlusion classically causes contralateral, homonymous hemianopia with macular sparing; neurons that process visual information from the macula are supplied by the middle cerebral artery. Educational objective: Cervical spine trauma can lead to dissection of the vertebral artery, resulting in infarction of the lateral medulla and causing vertigo/nystagmus, ataxia, loss of pain/temperature sensation in the ipsilateral face and contralateral body, bulbar weakness, and ipsilateral Horner syndrome.

A 30-Year-Old Man Comes to the Emergency Department Due to Severe