Wiler, Jennifer L. MD, MBA
A 32-year-old woman presents with dizziness. She fell a week earlier while line dancing, and has some residual neck stiffness. She then obtained two sessions of chiropractic cervical manipulation.
Since then her neck pain has been worse. She has nausea and vomiting, and feels like the room is “spinning,” but she has no focal weakness or headache.
Here is her CT angiography study. What does it show?
Poor Hand Washing in Hospitals
Health care workers who wear gloves while treating patients are less likely to clean their hands before and after patient contact, according to a study published in the December issue of Infection Control and Hospital Epidemiology. (2011;32:1194.)
The study, which was led by Sheldon Stone, MD, of the Royal Free Hospital NHS Trust, observed more than 7,000 patient interactions in 56 elderly intensive and acute care wards in 15 UK hospitals. It found that hand hygiene compliance was “disappointingly low” at 47.7 percent, and it was even lower (41%) in instances where gloves were worn.
“The chances of hands being cleaned before or after patient contact appear to be substantially lower if gloves were being worn,” said Dr. Stone. “We call this the phenomenon of the ‘dirty hand in the latex glove.’”
When contact with body fluids is anticipated, glove use is appropriate. But gloves should not be considered a replacement for hand hygiene practices. Gloves reduce the number of germs transmitted to the hands, but germs can sometimes get through the latex, and hands also can be contaminated by back spray when gloves are removed.
Quick Consult: Diagnosis: Vertebral Artery Dissection
Dr. Wiler is an assi...Image Tools
Vertebral artery dissection is a rare but potentially deadly cause of stroke in young and middle-aged adults. The annual incidence of spontaneous vertebral artery dissection is approximately 1 to 1.5 per 100,000 (Can J Neurol Sci 2008;35:146) and purports a mortality rate of nearly 10 percent. (Can J Neurol Sci 2000;27:292.)
The vertebral artery arises from the first branch of the subclavian artery. It then runs through the transverse foramina of the cervical vertebra at C6 (or at times C5 or C7) to C2, where it then takes a posteriolateral turn around the posterior arch of C1 (atlas) to then traverses through the suboccipital triangle before entering the foramen magnum where it pierces the dura and joins the basilar artery at the junction of the pons and medulla. This tortuous route proximally puts the vessel at risk of damage from typically minor traumatic rotational neck injuries.
Dissection of the vertebral artery is the result of an intramural expanding hematoma, which can be spontaneous or the result of trauma. Approximately one percent of all patients with blunt injury mechanisms develop a traumatic dissection. (Can J Neurol Sci 2000;27:292.) Risk factors include cervical chiropractic cervical manipulation (Int J Clin Pract 2010;64:1162), history of hypertension, oral contraceptive use, female gender, chronic headaches/migraines, yoga, intrinsic vascular pathology, direct laryngoscopy (J Laryngol Otol 2009;123:e11), and rarely dental procedures (J Can Dent Assoc 2010;76:a82).
Various forms of vertebral artery dissection exist. A subintimal hematoma may rupture back into the vertebral artery and create a false lumen, or it may traverse deep into the brain causing partial or complete obstruction of the arterial branches resulting in regional brain infarction. A subadventitial tear may cause lateral dilatation (pseudoaneurysm) and cause compression and infarction of local tissues, or may rupture through the adventitia, resulting in a subarachnoid hemorrhage. A small hematoma may wall off and remain asymptomatic. Intimal disruption, however, impedes local flow, and causes thrombosis and may result in distal ischemia or infarction. Accounting for only two percent of all ischemic strokes, dissections are a rare etiology of stroke overall, but they are responsible for as many as 20 percent of strokes in patients under 45. (Can J Neurol Sci 2000;27:292.)
Patients can present with signs of acute severe intracranial hemorrhage or stroke. Signs and symptoms may be more subtle, however, and develop days, weeks, or months after a minor injury. These include bulbar signs and symptoms including ipsilateral pain and numbness, hoarse voice, hiccups, vertigo, dysarthria, posterior headache, neck pain and stiffness, nausea and vomiting, and dizziness or feeling off balance.
Findings on examination depend on the extent of brain injury from ischemia or infarction in the brain stem or cerebellum, but can include hemianopsia, cerebellar signs including ipsilateral gait ataxia, pass pointing, diplopia, oscillopsia (oscillation of objects in visual field), ocular torsion, nystagmus, lateral medullary dysfunction (Wallenberg syndrome or posterior inferior cerebellar artery syndrome) with loss of pain and temperature sensation on the ipsilateral side of the face and contralateral trunk and limbs (Rev Neurol 2003;37:837), ipsilateral Horner syndrome (seen in as many as one-third of patients [Lancet Neurol 2009;8(7):668]), dysphagia, medial medullary syndrome (tongue deviation to ipsilateral side, contralateral hemiplegia, and loss of vibration and proprioception), or internuclear ophthalmoplegia.
The differential diagnosis includes other etiologies of stroke (ischemic or hemorrhagic), headache, or vasculitis. It also includes cervical spine fracture and sprain as well as subarachnoid and intracranial hemorrhage.
The diagnosis of vertebral artery dissection can be made by either CT angiography or MRI/MRA. (AJR Am J Roentgenol 2009;193:1167.) The classic teaching is to identify the marked intralumenal narrowing that creates a string-and-pearl appearance of the stenotic vessel. Laboratory tests like coagulation studies are necessary if the diagnosis is confirmed and anticoagulation therapies are initiated.
The current standard treatment of a vertebral artery dissection is anticoagulation therapy once contraindications to anticoagulation have been ruled out (such as SAH). The theory is that this prevents the deleterious effects of thrombotic or embolic complications. Interestingly, no randomized controlled studies have been performed to validate this practice. (Cochrane Database Syst Rev 2003;:CD000255.) Patients in extremis, including those with intracranial or subarachnoid hemorrhage, should be managed by standard resuscitation protocols. Patients with a confirmed diagnosis of vertebral artery dissection warrant an emergent neurosurgical consultation.
Endogenous vascular healing is expected within three to six months, with occlusion recanalization occurring in nearly 50 percent of cases and stenosis resolution as high as 90 percent. With time, half of dissecting aneurysms improve or resolve. (Can J Neurol Sci 2000;27:292.)
This patient was diagnosed with a left vertebral artery dissection. While in the hospital, surveillance imaging demonstrated the onset of a subsequent right side dissection. The patient was started on double anticoagulation therapy, and discharged to home without incident or neurologic deficit.
▪ Read all of Dr. Wiler's past columns in the EM-News.com archive.
▪ Comments about this article? Write to EMN at email@example.com..
© 2012 Lippincott Williams & Wilkins, Inc.