Hyperdense Middle Cerebral Artery Sign is Associated with Poor Recanalisation with Intra-Arterial Therapy

Background: The hyperdense middle cerebral artery sign [HMCAS]and hyperdense basilar sign [HBAS]are associated with poor outcome with thrombolysis [t-PA). Intra-arterial [IA]therapy is sometimes used in the management of acute anterior circulation strokes in addition to t-PA. The utility of these signs in stratifying outcomes with IA therapy is limited. We compared recanalisation rates with IA therapy in patients with and without the signs. Methods: Patients with anterior circulation stroke presenting less than 6 hours and posterior circulation stroke presenting less than 24 hours treated with IA were studied retrospectively. Admission CT scans were assessed for the signs. Good recanalisation was classified as TICI 2b/3 on angiography. Recanalisation in patients with and without the signs was compared. Results: Of the 210 patients, 181 were analysed. There were 85 patients in the HMCAS group; 41 in the HBAS group and 55 in the group without any sign. The median age and NIHSS score was similar between each group. The HMCAS was found to be a negative predictor of recanalization [odds ratio of 0.4. p<0.05]The HBA sign did not predict recanalisation. The HMCAS group had a faster mean onset to recanalisation time when compared with the HBAS and no sign group [HMCAS 332.6mins, HBAS 561.9 and No sign 403.6, p=0.0002). IV t-PA prior to IA therapy was a favourable predictor of recanalisation [OR 5.1). Conclusion: We found the presence of the HMCAS sign to be poorly predictive of establishing good recanalisation with IA therapy. This may be used for planning of treatment approaches in future IA studies.