Purpose or Case Report: 1) Review the normal development and anatomy of the middle cranial fossa.
2) Describe the variety of pathologies affecting the middle cranial fossa in the pediatric age group with a focus on the typical computed tomography (CT) and magnetic resonance imaging (MRI) characteristics.
3) Discuss clinical management and imaging follow up of middle cranial fossa pathology.
Methods & Materials: We reviewed cases of skull base lesions involving the middle cranial fossa at our institution for a pediatric population (ages 0 to 18 years). Representative cases including brain CT and MRI studies were selected and their images were collected for presentation. This exhibit will review the wide range of etiologies of middle cranial fossa lesions with a focus on imaging findings of benign and malignant conditions. Typical and unusual cases will be presented with particular emphasis on characteristic CT and MRI imaging findings.
Results: The middle skull base is formed by the sphenoid bone anteriorly, greater wings of the sphenoid laterally, and posteriorly by the temporal bone anterior to the petrous ridge. The body of the sphenoid contains the tuberculum sellae and sella turcica. There are also several foramina with nerves and vessels traversing the middle skull base. Clinical presentation frequently occurs following involvement of adjacent anatomic structures, which may cause neurovascular complications. Entities involving the middle skull base can be classified as:
1) Congenital lesions including encephaloceles and variable pneumatization.
2) Traumatic lesions such as basilar skull fractures most associated with fatalities.
3) Malignancies including rhabdomyosarcoma, osteosarcoma and perineural tumor spread.
4) Benign lesions including craniopharyngiomas, pituitary adenomas, juvenile nasopharyngeal angiofibromas, cholesterol granulomas, meningiomas, and schwannomas.
5) Infections including bacterial and fungal etiologies causing mastoiditis, petrous apicitis, and skull base osteomyelitis.
Conclusions: Knowledge of normal development of the skull base is essential in pediatric patients to avoid over diagnosis as malignant and aggressive lesions are less frequent when compared to the adult population. This exhibit will present the wide-range of middle skull base pathology in the pediatric patient population with a focus on characteristic imaging findings distinguishing between benign and malignant conditions.