Successful conservative treatment of an intracranial pneumatocele with post-traumatic hypoglossal nerve palsy secondary to diffuse temporal bone pneumocele: case report and review of the literature

Abstract

While most patients with otogenic pneumatoceles have presented acutely in extremis secondary to tension pneumocephalus, our patient has remained largely asymptomatic. Aetiology, clinical features and management options of temporal bone pneumoceles and otogenic pneumatoceles are reviewed.

Post-traumatic temporal bone pneumatocele presenting after aggressive Valsalva

“…In many of the cases we reviewed, hyperpneumatisation of the temporal bone is observed without prior trauma, and the air space is initially contained within the bone. The defect often does not present clinically until a pneumatocele forms in adjacent soft tissue,1 5 7 9 10 12–15 17 or the thinning bone fractures 2 4 6 11. Both of these manifestations have been attributed to minor trauma in several cases 2 6 7 10–12.…”

“…The defect often does not present clinically until a pneumatocele forms in adjacent soft tissue,1 5 7 9 10 12–15 17 or the thinning bone fractures 2 4 6 11. Both of these manifestations have been attributed to minor trauma in several cases 2 6 7 10–12. It is proposed by Massman et al 12 that microfractures of the thinned bone can lead to soft tissue emphysema, and that special care should be taken with regard to air in the epidural space because of possible communication with the external environment.…”

“…The mastoid part of the temporal bone is normally air-filled, and its antrum is in communication with the middle ear space. Eleven of the 17 cases referenced above reported an association between hyperpneumatisation and increased middle ear pressure or frequent Valsalva manoeuvres 1 2 5–7 9 11–15. However, no cases of pneumatisation at the site of a prior mastoid bone fracture have been reported.…”

“…A pneumocele is a rare condition described as an abnormally enlarged intraosseous collection of air, with diffuse thinning of the surrounding bony walls 1. When the air collection extends into the surrounding soft tissue, it is termed a pneumatocele 2. When the air extends intracranially, it can be termed pneumocephalus 3…”

“…Pneumoceles more commonly present in the paranasal sinuses,2 but at least 17 cases of mastoid sinus origin have been reported 1 2 4–17. The mastoid part of the temporal bone is normally air-filled, and its antrum is in communication with the middle ear space.…”