The Value Of Susceptibility Weighted Imaging Technology For Ischemic Cerebrovascular Diseases

BackgroundCerebral infarction is the most common among ischemic cerebrovascular diseases and approximately accounts for 70%. Thrombolytic therapy is more effective for treating cerebral infarction, especially for early treatment. However, it is necessary to consider if hemorrhage has been discovered, and thrombolytic therapy is infeasible in case of hemorrhage, or else severe consequences will be caused, because some concealed hemorr-hage has unclear clinic manifestations, even has no clinic symptoms and is undetectable for routine imaging examination. Special imaging methods will play certain roles in guiding clinic therapies as long as they are applied in the early period to discover hemorrhage in time. SWI is highly advantageous in treating secondary hemorrhage and hematoma, particularly micro bleed of cerebral infarction. Nevertheless, this examination method isn’t used often in clinic practices, especially in some hospitals of cities smaller than medium-sized cities. In China, no research has developed unified or routine combinations of this method about the disease.ObjectivesSusceptibility weighted imaging (SWI) was applied in imaging examination of hemorrhagic transformation of cerebral infarction. Then, imaging manifestations of routine MRI and SWI were acquired for comparison, in order to discuss the advantages of SWI in hemorrhagic transformation of cerebral infarction.Methods380 patients hospitalized in the hospital from July 2013 to December 2014 were scanned via routine MRI (T1WI and T2WI) and axially scanned by DWI and SWI with a 1.5TMR scanner. By using the ADW4.2 workstation equipped for magnetic resonance, a collection of SWI images were processed with post-processing software to automatically obtain calibrated phase images and negative phase masks. Then, images were obtained by minimum intensity projection. Four groups of images were available for each patient, including T1WI, T2WI, DWI and SWI, which were comparatively analyzed.Results60,32,38 and 45 cases were detected to suffer from hemorrhagic cerebral infarction by SWI, T1WI, T2WI and DWI respectively. Secondly,40,45,53 and 76 hemorrhage foci were detected by T1WI, T2WI, DWI and SWI respectively. Thirdly, SWI presented a larger extent of hemorrhage in all cases compared with T1WI, T2WI and DWI. Fourthly, SWI could detect micro-veins and slight hemorrhage.Conclusion1. For ischemic cerebrovascular diseases, SWI may detect more hemorrhage foci and larger area of hemorrhage in case of hemorrhage as compared with routine MR imaging (T1WI and T2WI) and DWI.2. SWI may detect hemorrhage foci and concealed slight hemorrhage of cerebral infarction earlier, so it can somewhat guide the determination of clinic therapies. Thus, situation of cerebral infarction may be pertinently monitored, examined and followed up.3. SWI may clearly display micro veins around foci. The detection of micro veins gives a clue of collateral circulation around patients’infarction zones, and the clue is positive for rehabilitation in clinic practices.4. SWI sequence is suggested to be set for MRI scanning of patients with cerebral infarction since it is of great importance for monitoring the disease and promptly adjusting therapies.