Detection of Microhemorrhages in Cerebral Amyloid Angiopathy by Susceptibility Weighted MR Imaging – An Observational Study

ABSTRACT

Introduction: Cerebral amyloid angiopathy (CAA) is acause for approximately 10-20% of spontaneous intracerebralhaemorrhage in elderly population. Susceptibility weightedimaging (SW1) is a new imaging method is clinically usefulfor evaluating the presence of chronic blood products in thebrain, especially clinically silent microbleeds associatedwith cerebral amyloid angiopathy. Aim of this study was todetermine the advantages of Susceptibility weighted imaging(SW1) over conventional gradient echo (GRE) technique in aprobable diagnosis of Cerebral amyloid angiopathy.Material and Methods: All patients more than 55 yrspresented with neurological signs and symptoms referredfor neuroimaging, were subjected to image with MRI usingT1W, T2W, FLAIR. AXIAL 2D MERGE, Diffusion weightedimaging (DWI) including apparent diffusion coefficient(ADC) and Susceptibility weighted imaging (SWI). Thosecases having multiple macro and micro haemorrhagesinvolving cortical and sub cortical region detected by eithergradient or SWI included in the study.Results: Sudden onset of neurological deficit was the mostcommon symptom which accounted for 37% of cases.Cortical and sub cortical regions are most commonly involvedsites. On comparison between gradient and SWI, 11 caseshaving micro hemorrgages detected only by SWI and absentin gradient.Conclusion: GE - T2* MR imaging is currently the “ standard”for identifying microhemorrhages and diagnosing cerebralamyloid angiopathy based on number and distribution of microhaemorrhages. SW1 identified many more microhemorrhagesthan conventional T2* weighted GE magnitude technique andmay lead to earlier diagnosis of patients with CAA.