The purpose of this study was to examine the current investigative practices of patients with symptoms of a possible posterior circulation stroke. A retrospective cohort study was performed at a single tertiary hospital to determine whether there had been an increase in the number of CT requested and whether this suspected increase was substantiated by a greater number of strokes detected.

Background A posterior circulation stroke (PCS) is an uncommon disease that encompasses the potentially fatal basilar artery occlusion to the vertebral artery dissection. Early recognition of PCS is often delayed when compared to the anterior circulation strokes[1] as PCS is uncommon and it present with varied symptomatology such as dizziness, unilateral limb weakness, gait ataxia and nystagmus[2]. The rapid diagnosis of PCS is paramount in determining the efficacy of treatment as thrombolysis[3] and thrombectomy[4]. Due to its cost-efficiency and speed of access, CT angiography remains...

Results Study population: 292 male, 355 female. Average age: 65 (SD:16.2). 647 CT scans over the 5-year period were included. 46 CT scans were positive for pathology within the posterior circulation (7%). In 2016 there were 51 studies performed, 5 of which were positive (9.8%). In 2020 there were 253 studies performed, of which 14 were positive (5.5%). The subgroup analysis was performed on 150 patients who underwent a CTA in 2020. 40 patients who had a CTA went on to have an MRI, of...

Conclusion: There has been a shift in the clinical practice, with a heavier reliance upon CT angiograms for the investigation of possible posterior circulation strokes. The request rate has increased by almost 500% while the detection rate has nearly halved.

S. Wellman: Nothing to disclose A. McLaughlin: Nothing to disclose T. Pham: Nothing to disclose M. Bynevelt: Nothing to disclose

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