Objective:To explore the MRI features of cerebral amyloid angiopathy-related inflammation (CAA-ri).Methods:The clinical and imaging data of 12 patients with CAA-ri diagnosed in Affiliated Guizhou Aviation Industry Cor Ltd No 300 Hospital of Zunyi Medical University (9 cases), Xingyi People′s Hospital (2 cases) and Anshun people′s Hospital (1 case) from June 2013 to June 2020 were analyzed retrospectively. There were 3 females and 9 males, aged from 57 to 89 years old, with an average age of 71±10 years. The twelve patients included 5 cases with probable CAA-ri and 7 cases with possible CAA-ri. The duration of the disease ranged from 30 minutes to 2 years. One patient has ApoE ε4/ε4 gene overexpressed. All the 12 patients underwent MRI, including susceptibility weighted imaging in 12 cases, DWI in 10 cases, contrast enhanced MRI (CE-MRI) in 9 cases, MRS in 3 cases, MRA in 7 cases, and perfusion-weighted imaging in 1 case.Results:Imaging features of CAA-ri included encephalopathic, tumoral, classical cerebral amyloid angiopathy(CAA) manifestations. Twelve cases of encephalopathic manifestations showed patchy white matter hyperintensity (WMH) involving U-shaped fibers on T 2 weighted fluid-attenuated inversion recovery sequence (FLAIR), usually asymmetric,with various degree of mass effect, no diffusion restriction on DWI and no enhancement on CE-MRI. One case showed a single tumoral lesion with irregular enhancement on CE-MRI. The classic CAA findings included hemorrhagic lesions (microhemorrhage in 8 cases, lobar hemorrhage in 6 cases, subarachnoid hemorrhage in 3 cases, iron deposition on the brain surface in 7 cases) and ischemic lesions (microinfarction in 1 case, enlarged perivascular space and interlobar space in 4 cases). Follow-up showed lesions absorption and/or new lesion formation in 5 cases. Conclusions:The MRI features of CAA-ri are mainly patchy WMH involving U-shaped fibers on T 2 FLAIR, usually asymmetric, with wandering and alternating features, and inconsistency with clinical manifestations.