Heterotopic Neuroglial Tissue in Sphenoid Ridge.

BACKGROUND

Extracerebral neuroglial heterotopias are rare manifestations of cerebral tissue outside the brain whose most common form is the so-called nasal glioma. In this case report we illustrate the first case of heterotopic neuroglial tissue within the bone of the skull.

CASE DESCRIPTION: Our patient underwent surgery for a sphenoid ridge meningioma. Aside from the expected meningioma, histopathologic examination showed a small amount of intraosseous heterotopic neuroglial tissue.

CONCLUSIONS

The pathogenesis of cerebral heterotopias is diverse. Most of the midline lesions are probably residuals of former meningoencephaloceles. The pathogenesis of extracranial nonmidline lesions is more questionable. Their cause might be a former trauma, inflammatory disease, or surgery. Another option is that they represent primary neuroglial heterotopias, as it is supposed for manifestations of the lung. The coexistence of a heterotopia and a meningioma in this case is probably a coincidence. It is also debatable whether the broad tumor extension within the bone and/or the heterotopia might go back to alterations of the bone structure.