WED 261 Stroke scan agnosia – what radiologists do not see

Abstract

BackgroundNeuroimaging helps clinicians make accurate diagnoses. Most stroke patients have their imaging reported by general radiologists.MethodsAs part of a quality assurance program a database for neurological patients with second opinion reporting from neuroradiologists was searched from 2008 to 2016 to identify patients in whom stroke lesions were missed at initial reporting by general radiologists. Patient demographics, scanning modality, stroke type, location and laterality were recorded.Results36 patients, 18 men, 18 women, mean age 59.0 (SD 13.8) years were identified in whom a stroke lesion was not detected on initial reporting. The lesions included cerebellar infarcts in 14 patients (bilateral in 3), pontine ischaemia/infarction (n=6), supratentorial infarction (n=9), vessel abnormality (n=6 – dense middle cerebral and basilar arteries, dissection and cerebral venous sinus thrombosis), and spinal infarction (n=1). In 9 (24%) patients the missed lesions occurred solely on CT brain scanning. The missed lesions were acute presentations in 8 (22%) patients.ConclusionStroke lesions can be missed with both CT and MRI. The posterior fossa and dense artery signals (middle cerebral artery and basilar artery) are prone to detection errors.