The planum semilunatum is located on the lateral side of the crista ampullaris of thesemicircular canal. With regard to the functions of the planum semilunatum, some researchers assume the existence of secretory activity based on the microstructural features observed in isotopic experiments. In the present study, in order to confirm the existence of an immunological mechanism in the ampulla of the semicircular canal, the distribution of immunoglobulins in the semi-circular canal of guinea pigs was investigated immunohistochemically. Positivity of IgG wasobserved in the constituent cells of the planum semilunatum or beneath the basement membrane ofthe cells.It is concluded that ample IgG, which is an important constituent of the body fluids, is collected within this region. The planum semilunatum containing such ample amounts of IgG might be involved in the immunological mechanism operating in the ampullar of the semicircular canal.

Fraser Syndrome is a rare autosomal recessive disorder (Gupta and Saxena, 1962; Smith, 1982). The most consistent feature is cryptophthalmos (hidden eye), but frequently abnormalities of the ears (meatal stenosis, dysplastic pinna), nose (hypoplastic notched nares, choanal stenosis or atresia), and larynx (glottic web, subglottic stenosis), as well as numerous other anomalies are encountered. We present four cases that have been treated at the Hospital for Sick Children in the last ten years, and describe the various ENT anomalies characteristic of this syndrome.

The relationship between temporal bone pneumatization and the location of the lateral sinus and length of the mastoid process was investigated in 60 fresh frozen adult temporal bones, by plain X-rays, computed tomography and surgical dissection including otomicroscopic findings. Temporal bone pneumatization was classified as small, moderate and large. After drilling, the shortest distances between the middle fossa dura and mastoid tip representing the mastoid length and between the sigmoid sinus and posterior border of external auditory canal were measured and compared to the degree of pneumatization. The distances in the specimens with pathological eardrum and adhesions in the middle ear were compared to the ones without gross pathology. The length of mastoid process was significantly shorter in specimens with small pneumatization than those with large (Mann Whitney P<0.001).

The specimens with a pathological eardrum and middle ear adhesions had a significantly shorter mastoid length than those without gross pathology. There was no significant difference between degree of pneumatization and the shortest distance between sigmoid sinus and external auditory canal (Mann Whitney P>0.05). It is demonstrated that the ‘under-developed’ mastoid process can be a consequence of hampered pneumatization.

The TNM-classification of laryngeal carcinomas of the UICC contains a number of weaknesses which diminish their prognostic relevance. Based on clinical observations and microscopic investigations of surgical specimens, several changes are proposed to improve the existing TN-classification.

The larynx is subdivided by the UICC into the supraglottic, the glottic and the subglottic main area and their tumours. There are embryological, anatomical, functional and oncological reasons to divide the larynx into two main areas only—the supraglottis and the glottis (vocal folds) without any further subsites and to abandon a separate group of subglottic tumours. The T size of a tumour should not be assessed according to the extent of an ill-defined anatomical region, but measured in millimetres of greatest surface extent only. The T2 category of vocal fold tumours should not contain those which lead to an inhibited mobility of the fold. All tumours with reduced vocal fold mobility or fixation should be classified as T3 or T4 according to the dimension of invasion. Post-operative pathological examinations (pT/pN) allow an assessment of the true extent of a tumour in three dimensions. A validation study using a ‘metric’ T pT-classification shows very distinct groups of tumours with a significantly different prognosis from Tis 1 to T4. Studies of lymph node metastases in the neck have shown that, number, size, site of metastasis and the presence of extracapsular tumour spread have a significant influence on the prognosis. An improved N/pN-classification taking these factors in consideration is proposed.

Pre-operative Computerized Tomography was performed prior to second look operations in 10 cases to check for cholesteatoma after combined approach tympanoplasty. Three independent opinions were obtained on the CT scans and compared with the operative findings.

This small series failed to demonstrate reliable pre-operative radiological detection of cholesteatoma. There was disappointing inter-observer agreement in interpretation of the CT scan

A review of 3,488 tonsil and adenoid procedures performed between March 1987 and April 1990 is presented.

A reactionary haemorrhage rate of 0.49 per cent was found. No deaths were recorded. All cases of reactionary haemorrhage occurred within the first eight hours post-operatively.

Based on this study, out-patient tonsil and adenoid surgery should be followed by at least an eight hour post-operative observation period before discharge. If day case adenoid and tonsil surgery is adopted, close medical audit would be necessary to detect and then prevent any possible increase in morbidity or mortality.

The use of a polymaleinate glass ionomer cement in 80 neuro-otology cases is described. It has pf oved of great value in translabyrinthine acoustic neuroma surgery, reducing the incidence of CSF fistula to nil. It is the method of choice for fixation of the Nucleus cochlear implant, and has many other applications in the field of otology and neuro-otology. It is easy to use and appears to have no side effects.

Six cases of otitis media with effusion associated with Chlamydia pneumoniae, a currently recognized respiratory tract pathogen, are presented. The organism was isolated from the middle ear fluids and serological evidence confirmed it as the infectious agent. The study population is small; however, these reports suggest C. pneumoniae as a causative agent of middle ear diseases.

Malignant external otitis is a progressive pseudomonal infection of the external auditory canal and adjacent structures. In the literature there is no unified policy regarding the management of malignant external otitis. The development of an effective nuclear scanning method and antibiotics active against Pseudomonas aeruginosa have helped in formulating our management policy. A review of four years personal experience with this condition is presented. All of our cases were cured from the disease with no fatality. Gallium67 citrate scans showed that antipseudomonal treatment should continue for up to three months.

Successful replacement of the sound conducting mechanism of the ear has been hampered by infection, perforation, prosthesis instability and extrusion. In this animal study on thirty rats a silicone prosthesis was inserted between two layers of fascia as a total replacement of the tympanic membrane and ossicular chain. After four months the graft was found to be intact without evidence of infection or extrusion in all but one of the 30 rats. These results justify a trial of a similar silicone prosthesis in humans.