Osteomyelitis of the central skull base: Otogenic and odontogenic sources. Multidetector CT study

Dental findings on face and neck imaging

When it is necessary to evaluate dental structures, the typical method is to obtain intraoral or panoramic X-rays at specialized dental clinics. However, in the daily practice of head and neck radiology, or even general radiology, it is common to encounter clinical situations or examination findings related to dental problems that should not be ignored. Because such problems can often be responsible for the clinical complaints of patients, this review aims to assist radiologists in identifying and describing common dental conditions on computed tomography of paranasal sinuses, face, and neck. It is important for radiologists to have knowledge of dental arch anatomy and its relationships with facial structures, as well as of major dental pathologies, including periapical sclerotic lesions, odontogenic cysts, fistulas, and abscesses, together with knowledge of incidental findings without clinical repercussions, which should be easily identified and stressed by the radiologist when necessary. The imaging methods most commonly used in evaluation of paranasal sinuses and face are computed tomography and magnetic resonance imaging. Those methods allow radiologists to recognize and become familiar with the main dental findings. The description of such findings by a radiologist can lead to a change in treatment strategy.

A Case of Atypical Central Skull Base Osteomyelitis with Bilateral Alveolar Bone Destruction

Central skull base osteomyelitis (CSBO) is a rare, fatal condition seen mostly in elderly diabetic or immunocompromised patients; it mainly involves the sphenoid or occipital bones and diagnosis is often delayed. A 72-year-old male with diabetes was referred to our department with severe pain in the maxillary gingiva. Endoscopic biopsy of the pterygoid bone confirmed the presence of mucormycosis combined with Klebsiella pneumoniae infection. Sinus surgery was performed with bilateral alveolar bone sequestrectomy. Long-term intravenous broad-spectrum antibiotic therapy using meropenem and ampicillin/sulbactam and antifungal therapy using amphotericin B (100 mg/day) was administered; an oral antifungal agent, posaconazole (800 mg/day), was also prescribed for 11 weeks. At the 6-month follow-up visit, there were no complications and no progression of the CSBO lesion was observed. Timely diagnosis and multidisciplinary treatment including endoscopic surgery, alveolar bone sequestrectomy, and combined antifungal and antibiotic therapy can reduce mortality and minimize complications associated with CSBO.

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.