Indexed on: 01 Mar '06Published on: 01 Mar '06Published in: Klinische Neuroradiologie
In the anterior circulation, the hyperdense middle cerebral artery sign (HMCAS) is a well established marker for early ischemia. Similarly, the hyperdense basilar artery sign may be a diagnostic clue for basilar artery thrombosis. Other hyperdense artery signs have not yet been described. The purpose of this study was to define the hyperdense posterior cerebral artery sign (HPCAS) and determine its incidence, diagnostic value, and reliability as a marker for ischemia in the territory of the posterior cerebral artery (PCA).CCTs of 69 patients with proven acute ischemia in the PCA territory were compared by three independent and blinded readers to the CCTs of 86 age-matched patients without PCA infarction. Using follow-up imaging, the correlation of the HPCAS with infarct size, thalamic infarction and bleeding were investigated.A HPCAS was found in 37.7% of all patients with PCA-infarction, typically within the ambient cistern with a specificity of 95.4%. The thalamus was affected significantly more often (p = 0.03), and the size of the infarct was significantly more often large than medium or small (p = 0.02) when a HPCAS was present. Hemorrhagic transformation tended to occur more often when the HPCAS was present.HPCAS was detected in more than one third of all patients with PCA ischemia, suiting the incidence of the HMCA. Based on our results, this sign may not only be helpful in the early diagnosis of PCA infarction but might also act as a prognostic marker in acute PCA territory ischemic stroke.