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There is an ill defined low density centred upon the left masticator space consistent with a collection. The abnormality involves the medial aspect of the masseter muscle and the lateral pterygoid. The approximate dimensions are 1.2 x 3.0 x 4 cm in orthogonal planes (Trans x AP x CC). The craniocaudal extent of the lesion is likely is greater than 4 cm due to difficulty in accurate measurement. There is inflammatory generalised stranding within the left masticator space with obliteration of the fat posterior to the left maxillary wall. There is mild trans-spatial extension of the left masticator space infection with inflammatory stranding identified within the left parapharyngeal space. There is no further extent into the lower neck or upper mediastinum.

Removal of 4 mandibular and maxillary wisdom teeth. The left mandibular wisdom tooth socket is presumably the source of infection. Note is made of lucencies within the posterolateral wall of the maxillary sinus bilaterally. On the right this appears to be a fracture presumably related to extraction. On the left appearances are similar.

There are multiple enlarged left deep cervical lymphadenopathy likely reactive in nature.

Conclusion

Findings in keeping with a left masticator space phlegmonous collection. No extension into the lower neck or mediastinum.