Osteomas of the paranasal sinuses are common. Most are, however, asymptomatic and a chance radiographic finding. We describe four case histories which help to illustrate the benefits and hazards of surgery, and highlight the importance of patient selection. A review of the literature is presented.

The temporal bone pathology of a 74-year-old female affected by vestibular schwannoma was compared with findings of auditory brainstem response and electrocochleography. At age 71, she complained of hearing loss in the left ear in which pure tone audiometry revealed threshold elevation in the middle- and high-frequency range. Temporal bone CT scanning revealed a medium-sized cerebellopontine angle tumour in the left ear. ABR showed no response in the left ear, but the electrocochleography showed clear compound action potentials. Three years later, at age 74, she died of metastatic lung cancer and sepsis. The left temporal bone pathology consisted primarily of a large vestibular schwannoma occupying the internal auditory meatus. The organ of Corti was well preserved in each turn. In the modiolus, the numbers of spiral ganglion cells and cochlear nerve fibres in each turn were decreased. These histological findings suggest that clear compound action potentials were recorded from the distal portion of the cochlear nerve in spite of the presence of the vestibular schwannoma, but ABR could not be detected because of the blockade of the proximal portion of the cochlear nerve by the vestibular schwannoma.

A rare case of pleomorphic adenoma of the base of the tongue with a relevant review of literature is reported.

We describe two cases of sphenoid sinus mucocoele. Both presented with isolated oculomotor nerve palsy. Mucocoeles involving only the sphenoid sinus are uncommon. They are probably under-diagnosed as they may be asymptomatic or cause non-specific symptoms. Nasal symptoms occur infrequently but the close relationship of the sphenoid sinus to the orbital apex means that ocular symptoms including cranial nerve palsies are a common presenting feature. Involvement of the third cranial nerve in isolation is rare but has important neurosurgical implications which must be excluded before this symptom is attributed to the sphenoid sinus.

Juvenile xanthogranuloma is an unusual condition of childhood. It commonly presents as cutaneous lesions normally localized to the dermis and is benign. A case report of a two-year-old girl with juvenile xanthogranuloma involving the right temporal bone (petro-mastoid region) which was locally destructive, is presented.

Three cases of primary non-Hodgkin's lymphoma of the larynx are described. Histologically, two tumours belonged to the category of low grade B-cell lymphomas of the small cell type (extranodal marginal zone B-cell lymphoma and lymphoplasmacytoid lymphoma), and the third was classified as a peripheral T-cell lymphoma of unspecified type. The clinical stage was IE in two cases, and IV in another case. In two cases, complete remission was obtained with radical radiotherapy. But in the other case, which was histologically lymphoplasmacytoid lymphoma, the response to radiotherapy was poor, and surgery was required. There was no relapse subsequent to treatment. Primary non-Hodgkin's lymphoma of the larynx is rare. Several reported cases have clinical features similar to those of MALT-type lymphomas arising in other extranodal sites. Although most of the reported cases have been cured with radiotherapy, in some cases dissemination to other extranodal sites may occur. Therefore careful periodic evaluation is imperative.

Chondroid syringoma or mixed tumour of the skin is a rare benign tumour which can present on the face. We present here the case of a patient who underwent an excisional biopsy of a small painless nodule in the soft triangle of the nose for cosmetic reasons. The clinical presentation, histology and treatment, with review of the relevant literature, is discussed.

Impaction of a foreign body in the larynx is a serious event. While inhaledforeign bodies may occasionally impact in the larynx especially in children, a laryngeal foreign body as a complication of percutaneous tracheostomy has not been reported in the literature. We describe the case of a fragment of a Seldinger wire retained in the larynxfor two years following a percutaneous tracheostomy and review the literature on the complications of this procedure.

The pathophysiology of otitic hydrocephalus remains controversial. It has been argued that involvement of the superior sagittal sinus, by, at least, a mural thrombus is a necessary component of this disease.

We present a case of otitic hydrocephalus where on magnetic resonance imaging (MRI) normal luminal and mural flow within the superior sagittal sinus is demonstrated. The presence of thrombus in the lateral venous sinus alone appears sufficient in this case to impede venous drainage of the intracranial contents into the neck and produce a rise in the cerebral venous pressure and a subsequent increase in the CSF pressure. The presence of a superior sagittal sinus mural thrombus is not required.

A case of head and meck actinomycosis presenting clinically and radiologically as a nasopharyngeal tumour is described.

The association of sensorineural hearing loss and ulcerative colitis is well documented and it is speculated that this is autoimmune in origin. A case in a 12-year-old boy is described, that initially responded to steroid therapy, but four years later resulted in bilateral, profound sensorineural hearing loss in spite of good control of his bowel disease. Immunological tests may provide a clue as to the aetiology of suspected cases of autoimmune inner ear disease. Immediate treatment with steroids with or without immunosuppressive therapy is essential as delay may lead to irreversible hearing loss.

Actinomycosis of the temporal bone is uncommon. There have only been 24 cases previously reported in the English literature. The responsible organism is Actinomyces israelii, an anaerobic filamentous Gram positive bacterium. While the cervico-facial region is the most common site of the disease, involvement of the temporal bone is rare. The diagnosis can sometimes be made clinically by identification of sulphur granules in a glue-like substrate but in all cases involving the temporal bone, the diagnosis has been made at histopathology. Effective therapy consists of surgery followed by the long-term administration of penicillin.

Sixty-one cases of bilateral immobile vocal folds were classified as traumatic (52.46 per cent), idiopathic (39.34 per cent) or iatrogenic (8.20 per cent). During follow-up the idiopathic group of patients had a better prognosis (p<O.O5) compared to the traumatic or iatrogenic group. A spontaneous recovery was seen in 58.33 per cent of cases in the idiopathic group, 56.25 per cent in the traumatic group and 40.0 per cent in the iatrogenic group within a period of one year. Patients who failed to show spontaneous recovery were either subjected to arytenoidectomy with fold lateralization, endoscopic fold lateralization or laser cordectomy, showing 70.0 per cent, 66.67 per cent and 80.0 per cent recovery respectively. These cases have been discussed.

Susac's syndrome is extremely rare and is characterized by the clinical triad of encephalopathy, retinal artery occlusion and deafness. A case of this rare syndrome is presented and for the first time the fluctuating nature of the hearing loss is demonstrated. The site and nature of the hearing loss has been investigated. The value of neural hearing loss as a method of monitoring the clinical severity is discussed.

Differential diagnosis of granulomatous lesions of the nasal mucosa is difficult. One of the possible causes is an infection with Leishmania braziliensis as reported in this case. Therefore leishmaniasis should be included in the differential diagnosis of granulomatous lesions of the nasal mucosa in patients who have travelled to endemic areas.

A case of undifferentiated carcinoma of the nasopharynx presenting as a cervical mass associated with a paraneoplastic neutrophilic leukemoid reaction is reported. The diagnosis of undifferentiated nasopharyngeal carcinoma of the Regaud type was established by the presence of aggregates of epithelial neoplastic cells separated by areas of reactive lymphoid cells; the epithelial nature being confirmed by the positivity for epithelial markers (AE1/AE3, EMA). Serum IL-la, GM-CSF and TNFα remained undetectable suggesting that these factors were not involved in the occurrence of the paraneoplastic leukemoid syndrome.

True dermoid cysts of the oral cavity are rare, usually presenting as midline swellings in the floor of the mouth and occasionally elsewhere in the oral cavity. This report describes the diagnosis and management of a congenital dermoid cyst of the lateral aspect of the body of the tongue in a 10-year-old girl. The theories of the pathogenesis of this cyst during embryogenesis of the tongue are also reviewed.

Sinonasal malignant melanoma is rare and usually occurs in the nasal cavity. Presentation is often varied and occurs late in the natural history of the disease, resulting in a poor prognosis. A case is reported of a patient with malignant melanoma arising from the frontal sinus who presented with a forehead swelling and progressive confusion. A review of the literature on malignant melanoma in the nasal cavity and paranasal sinuses regarding its presentation, site of origin and principles of management is discussed.

A case of laryngeal squamous cell carcinoma recurrence presenting as multiple cutaneous metastases is presented. Such metastases are rare and are associated with a poor prognosis. Treatment is usually aimed at providing pain relief in these patients with a limited life expectancy.

A case of sensorineural hearing loss (SNHL) in MELAS syndrome, a variety of mitochondrial cytopathy, is presented. Mitochondrial cytopathies have gone almost unreported in the otolaryngology literature, despite evidence from a recent review that about 60 per cent of such patients suffer from SNHL (Gold and Rapin, 1994). The same review revealed that only one of 117 case reports in the period 1984–1993 contained an audiogram (Swift and Singh, 1988), and none presented sequential audiograms. However, audiometry has since been published on 23 members of a family with a mitochondrial point mutation causing only sensorineural hearing loss with no other symptoms (Vernham et al., 1994). We present a case of mitochondrial cytopathy three years after diagnosis with two sequential audiograms.