Evidence for ancient meningiomas and a probable case from Medieval Tarbat, Scotland.

We report the case of a probable meningioma in a cranium excavated from the Medieval site of Portmahomack on the Tarbat Peninsula in Scotland (Carver, 2008). Stratigraphic evidence enabled dating of the remains to a post-Pictish and pre-Reformation date. Meningiomas usually arise from the arachnoid membrane of the meninges (Yamazaki et al., 2001) and now represent approximately 20% of all primary intracranial tumours (Yener et al., 2009). They can result in hyperostosis of adjacent bone, osteolytic reactions, or both. We review the evidence for ancient meningiomas and describe a differential diagnosis of the pathology from the Tarbat cranium, including vascular and osteoid lesions, intracerebral malignancies, metastases and other benign lesions. The cranium that we present is from an adult male, and has a frontoparietal lesion approximately 3cm in diameter, which is characterised by bone growth and remodelling of the outer table, and endocranial bone destruction. Supporting photographic and radiological evidence is presented. We conclude that a diagnosis of meningioma is most likely in this case, and may represent the rarer primary extradural meningioma.