Dr Lucy Thomas

© 2017 National Stroke AssociationBackground Cervical artery dissection (CAD) is a leading cause of stroke among middle-aged adults, but the etiology is unclear. Some reports of seasonal variation in CAD incidence have been suggested but may reflect extreme climatic conditions. Seasonal variation may implicate more transient seasonal causes such as proinflammatory or hypercoagulable states. This study aimed to assess whether CAD incidence varied with season between UK and Australian sites. Also, this study aimed to determine whether there was a different pattern of seasonal variation between arteries (carotid and vertebral) and any association between CAD incidence and clinical factors. Methods This was a retrospective observational study of patients older than 18 years with radiological diagnosis of internal carotid or vertebral arterial dissection, from sites in Australia and the UK. Clinical variables were compared between autumn-winter and spring-summer and site of dissection. Results A total of 133 CAD cases were documented in Australia and 242 in the UK. There was a seasonal pattern to CAD incidence in countries in both the northern and the southern hemispheres, with a trend for dissection to occur more commonly in autumn, winter, and spring than in summer (incidence rate ratios [IRR] 1.4-1.5, P¿<¿.05). CAD counts were also slightly higher in internal carotid than in vertebral artery (IRRs 1.168, 1.43, and 1.127, respectively). Neither systolic blood pressure nor pulse pressure was significantly associated with CAD counts. Conclusions CAD occurs more commonly in cooler months regardless of geographical location, suggesting transient seasonal causes may be important in the pathophysiology. This effect was slightly higher in internal carotid than in vertebral artery, suggesting differing trigger mechanisms between dissection sites.

© 2015 Elsevier Ltd.Introduction: Cervical arterial dissection (CAD) is a common cause of stroke in young people under 55 years. It can occur spontaneously or subsequent to minor trauma or infection. The incidence is difficult to determine accurately as not all CAD progress to stroke. CAD is the most catastrophic adverse event associated with cervical manipulative therapy but it is rare. Early features of CAD can mimic a painful musculoskeletal presentation and a patient may present for treatment of neck pain and headache with a dissection in progress. Whether the manipulative technique is responsible for dissection or whether the diagnosis of CAD has been missed is unclear. Identification of individuals at risk, or early recognition of CAD could help expedite medical intervention and avoid inappropriate treatment. Purpose: The aims of this masterclass are to outline current research into the pathophysiology, aetiology and clinical presentation of CAD, to place the risk in context in a manipulative therapy setting and to discuss its possible clinical recognition. Implications: For those patients presenting with recent onset, moderate to severe unusual headache or neck pain, clinicians should perform a careful history, in particular questioning about recent exposure to head/neck trauma or neck strain. Cardiovascular factors may not be particularly useful indicators of risk of dissection. Clinicians should also be alert to reports of transient neurological dysfunction such as visual disturbance and balance deficits, arm paraesthesia and speech deficits, as these may be subtle. If clinicians suspect arterial dissection is in progress patients should be urgently referred for medical evaluation.