The role of imaging in skull base osteomyelitis - Reviewed.

PURPOSE: Skull base osteomyelitis (SBO) is difficult to diagnose due to a wide array of clinical presentations. It can be life threatening if not treated promptly. The objective of this study is to identify the various neck spaces involved in skull base osteomyelitis, correlate them with the possible source of infection and identify the related complications. METHODS: Eighty nine consecutive either culture proven cases of skull base osteomyelitis, or culture negative cases with inflammation on histopathology responding to antibiotic therapy, presenting at a single non-government hospital in south India between January 2016 and December 2018 were included in this study. Images were reviewed by two radiologists and imaging findings were documented by consensus. RESULTS: Involvement of the parotid space, retromastoid space and (temporomandibular) TM joint was associated with otogenic source of infection (p value < 0.05); while, retropharyngeal/prevertebral involvement was associated with sphenoid and nasopharyngeal sources (p value < 0.05). Complications such as cavernous sinus thrombosis (p value = 0.023) and ICA involvement (p value = 0.014) were more commonly seen with central skull base osteomyelitis. Abscess formation was seen in all three groups of patients without a significant difference between the groups. CONCLUSION: Imaging plays an important role in determining the possible source of infection by identifying the involved neck spaces and this in turn can guide the clinician to a site for biopsy. Complications related to SBO can also be identified on imaging and can guide appropriate management.

Imaging of retained surgical items: A pictorial review including new innovations.

With the advent of newer imaging modalities retained surgical items are now easily diagnosed by their characteristic imaging appearances. A combination of complementary imaging modalities helps to arrive at the diagnosis of this relatively rare complication. Factors contributing to their imaging features include the timing of diagnosis and imaging, presence of secondary infection, communication of the retained item with hollow viscus or external skin wound, and type of imaging modality used. A high index of suspicion is necessary for diagnosis before labeling it as a retained surgical item. In parallel with recent advances in surgery, it is essential that there is increasing awareness among radiologists regarding the newer types of retained surgical items.