HEAD AND NECK RADIOLOGY/ CT رادیولوژی و سی ی ت اسکن فک و صور ت
۳D IMAGING تصویربرداری سه بعد ی
BY DR AMIRAFRAZ FALAH, DR SOFIA SABOURI
Patient history:
A middle age woman with jaw malocclusion since a dental surgery 6 months ago
Imaging findings (CT scan)
Heterotopic Multicentric ossification of soft tissue is noted in patient’s face. This ossification has involved subtemporalis fossa at both sides.
Right masseter muscle, right lateral pterygoid, left medial and lateral pterygoid and left masseter muscle are involved in this multicentric heterotopic ossifcation. Also, involvement of inferior part of right temporalis muscle is detected.
Some heterotopic ossifications are also present adjacent to condyle of left mandible, which can lead to malocclusion.
Most of These ossified soft tissues show ground glass density.
These findings can be in favor of a heterotopic ossification process such as myositis ossificans traumatica of masticatory muscles . Correlation with previous imagings and clinical history is recommended.
Diagnosis: (with pathology confirmation):
Myositis ossificans traumatica
Myositis ossificans traumatica:
● Male patients have been considered as the main group at risk of developing MOT of the masticatory muscles with a male/female ratio of 2.4/1 .
● MOT has been frequently related to traumas (e. g. fracture, blow) a possible explanation could be: males might have experienced traumas more often than females
● prevalence for female patients of MOT of the masticatory musculature in context of dental treatment with a 1.5/1 ratio.
● In most cases of MOT of the masticatory muscles the masseter muscle is the most affected one. However, this is not true for those cases of MOT occurring after dental treatment. Of these cases, 66% involved the medial pterygoid muscle.
References:
https://head-face-med.biomedcentral.com/articles/10.1186/s13005-018-0180-6
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4196299/
