[CT and MRI features of diseases involving masticator spaces]

This is a study on the CT and MRI features of diseases involving the masticator spaces; the purpose is to improve the diagnostic accuracy.

Fifty-seven cases involving the masticator spaces were collected, among which, 11 cases were originated from the masticator space, another 46 cases were secondary invasion from the adjacent structures, including 18 cases from the buccal mucosa, 10 from the nasopharynx, 5 from the gingiva, 3 from the parotid gland, 6 from the maxillary sinus, 1 from the intracranial location, 2 from the palate and 1 from the orbit. The CT and MRI features of the masticator space involvement were analysed.

Masticator space involvement is visualized on CT and MRI as effacement of the fat plane, swelling of the masticatory muscles, and erosion of the mandibular ramus. Disease from surrounding structures can invade the masticator space via the pterygopalatine fossa, the buccal space immediately anterior to the ramus, the foramen ovale, or by way of direct invasion.

Masticator space involvement is not uncommon in the maxillofacial diseases, which must be noticed in the imaging diagnosis.