MRI of Orbital Cellulitis and Orbital Abscess: The Role of Diffusion-Weighted Imaging

Our aims were to describe the role of diffusion-weighted imaging (DWI) in detecting abscess as a complication of orbital cellulitis and to assess whether abscess can be diagnosed with a combination of conventional unenhanced sequences and whole-brain DWI with parallel acquisition. Nine cases of orbital cellulitis imaged with MRI were retrospectively reviewed, including six cases with pyogenic abscess. In this preliminary study, DWI improved diagnostic confidence in nearly all cases of orbital abscess when used in conjunction with contrast-enhanced imaging. DWI also confirmed abscess in a majority of cases without contrast-enhanced imaging, which may be of particular use when contrast material is contraindicated.