My son 11 ct scan right ear: what does it mean to have some mild membrane thickening in scattered mastoid air cells?

Mastoiditis: is an infection of the air cells of the mastoid sinuses, just behind the ear, a complication of otitis media. It is a more serious infection and requires specialized treatment. The CT finding you describe suggests there is no mastoiditis but possible low grade inflammation of some mastoid air cells . To prevent this make sure all ear infections are properly treated or tubes placed