Autoinflation devices are commonly used for otitis media with effusion and Eustachian tube dysfunction. Generally, these are very safe devices, with few or no complications.

This paper presents a case study of pneumocephalus and orbital emphysema, associated with the use of an autoinflation device, in a 73-year-old woman with Eustachian tube dysfunction and otitis media with effusion, and a history of extensive endoscopic sinus surgery 13 years previously.

A literature review showed autoinflation-related pneumocephalus in patients with skull base defects relating to cranial surgery or tumours; however, this has not been described previously with the Otovent system or its use in relation to functional endoscopic sinus surgery. Given the theoretical risk of undetected bony abnormalities in post-operative functional endoscopic sinus surgery patients, it is suggested that autoinflation devices are used cautiously in patients with a history of sinus surgery.

A pneumocele occurs when an aerated cranial cavity pathologically expands; a pneumatocele occurs when air extends from an aerated cavity into adjacent soft tissues forming a secondary cavity. Both pathologies are extremely rare with relation to the mastoid. This paper describes a case of a mastoid pneumocele that caused hypoglossal nerve palsy and an intracranial pneumatocele.

A 46-year-old man presented, following minor head trauma, with hypoglossal nerve palsy secondary to a fracture through the hypoglossal canal. The fracture occurred as a result of a diffuse temporal bone pneumocele involving bone on both sides of the hypoglossal canal. Further slow expansion of the mastoid pneumocele led to a secondary middle fossa pneumatocele. The patient refused treatment and so has been managed conservatively for more than five years, and he remains well.

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.

We report the case of a patient with extensive pneumocephalus extending into the lateral ventricles from a brain abscess arising from a cholesteatoma-induced defect in the skull base.

A 70-year-old man with cholesteatoma presented with right-sided otalgia, otorrhoea and progressive headaches. Computed tomography showed a tegmental defect (approximately 2 × 2 cm) at the right mastoid antrum. A T1-weighted, gadolinium-enhanced magnetic resonance imaging scan showed pneumocephalus in both lateral ventricles, which was directly connected to the mastoid cavity via a brain abscess and a bone defect in the skull base. Radical mastoidectomy was performed to remove the cholesteatoma. The roof of the mastoid cavity was covered extensively with fascia and a pedicled temporalis muscle flap. One week post-operatively, computed tomography and magnetic resonance imaging showed no pneumocephalus.

Pneumocephalus arising from a cholesteatoma-induced brain abscess and extending into the lateral ventricles is an important entity, with an atypical appearance on computed tomography and magnetic resonance imaging.

Spontaneous pneumocephalus is a rare condition that has been reported infrequently. Alien limb syndrome is an uncommon phenomenon most often seen in patients with frontal and callosal lesions.

Case report of a patient with pneumocephalus presenting with alien limb syndrome. The patient underwent successful surgical management. A literature review and discussion of aspects of this presentation are also included.

In this case, a spontaneous pneumocephalus has formed a frontal space-occupying lesion and presented with alien limb phenomena.