Electron microscopic observations and X-ray microanalysis of a multinucleated giant cell.

Giant cells and macrophages play important roles in defence and in reparative functions of the body. This paper describes a giant cell and macrophage present in an inflammatory mass in the temporal bone. X-ray microanalysis performed at the ultrastructural level revealed the presence of a very high iron content in the electron dense precipitates observed in both types of cells. The high iron content is probably due to phagocytosed haemosiderin, a breakdown product of free haemoglobin since there was evidence of haemorrhage present in the biological sections. As the tissue was chemically fixed, it also demonstrates that there is still a place for electron probe microanalysis in tissues (including archived specimens) which have undergone chemical fixation.

Otitis externa--the clinical pattern in a tertiary institution in Singapore.

Otitis externa is a common condition in the tropics. Most of the data related to the condition have arisen from Western sources. Locally, the aetiology and the pathogens identified have not been systematically studied. A prospective study involving 107 patients was conducted. Otomycosis was frequently encountered. Coagulase negative Staphylococcus and Aspergillus niger were the most common bacteria and fungus cultured respectively. Gentamicin and polymyxin B were the most effective topical agents against Pseudomonas aeruginosa. Self-cleaning of the ears was the most common predisposing factor.

Malposition of a long central venous catheter in the right inferior thyroid vein--a case report.

This case report hopes to bring to attention the possibility of malposition and ligation of a long central venous catheter in a central venous tributary in the course of major neck surgery. A 49-year-old gentleman underwent total laryngectomy and right radical neck dissection for laryngeal carcinoma. A long central venous catheter was inserted via the right basilic vein. This was subsequently found to have malpositioned into the right inferior thyroid vein and ligated. It required an exploration of the neck wound to remove the ligated catheter.

The future of stapedectomy--the Singapore problem.

Concern has been expressed in the recent literature regarding the problem of a dwindling number of stapedectomy cases and an increasing number of surgeons trained to do this operation. In Singapore, the problem is made worse by the very low incidence of this disease in its main ethnic groups of Chinese and Malays who together make up more than 90 per cent of the population. We report here an audit of 47 ears that underwent stapedectomy in a teaching hospital over a six-year period. The hearing results for consultants and surgical trainees were compared. Closure of the air-bone gap to within 10 dB was obtained in 64 per cent of Consultants' cases and 68 per cent of trainees' cases. These results fall short of the 90 to 95 per cent figure reported by experts in this procedure and only comparable to the less satisfactory results of several series recorded by residents in North America. We conclude that the unsatisfactory results arise from the small number of surgical cases available for each surgeon to improve and maintain his skills in a technically demanding procedure. It is proposed that such cases be directed to those pursuing otology as a subspecialty rather than all otolaryngologists in general.

Temporal bone chondroblastoma: big and small.

Chondroblastoma represents approximately one per cent of all primary bone tumours. It is even rarer in the temporal bone and so far only 34 cases have been reported. We report here two cases with chondroblastoma of the temporal bone. The first case was discovered as a small lesion of the attic and root of zygoma. It was removed via mastoidectomy and reconstruction of the bony defect achieved normal external ear canal anatomy and hearing post-operatively. The second case presented as an advanced tumour involving the infratemporal fossa and parapharyngeal space. It was treated surgically via the infratemporal fossa approach. As clear surgical margins were not obtained, post-operative radiotherapy was also given to minimize the chance of recurrence.

Malignant mesenchymoma of the retropharyngeal space.

Malignant mesenchymoma is a very rare head and neck tumour. To date only 15 cases have been reported in world literature and all in children under 16 years of age. We present here a case of a 40-year-old man with malignant mesenchymoma of the retropharyngeal space. The clinical picture is that of progressive dysphagia, voice change, snoring and dyspnoea. CT scan showed a soft tissue space-occupying lesion of the retropharyngeal space which enhanced very well with intravenous contrast. The tumour was excised in toto and the patient given post-operative radiotherapy. Histopathology showed two unrelated differentiated tissue types (bone and fat) in addition to the fibrosarcomatous element thus satisfying Stout's criteria (Stout, 1948) for a diagnosis of malignant mesenchymoma.

[Congenital cholesteatoma of the middle ear and mastoid. Apropos of 5 cases]. / Cholestéatome congénital de l'oreille moyenne et de la mastoïde: à propos de cinq cas.

Five cases of congenital cholesteatoma of the middle ear and mastoid as defined by Derlacki's criteria were encountered over a 14 month period. They make up 5% of all cases of cholesteatoma managed over the same period of time. Three were young children and all presented with unilateral hearing loss. One had associated multiple congenital abnormalities of the external and middle ear. Only in one patient was the diagnosis made on initial otoscopic examination and the remainder diagnosed on CTscan, myringotomy and tympanotomy. All were operated on; three by the intact canal wall technique, one by the canal down technique with mastoid cavity obliteration and one by atticotomy with lateral attic wall reconstruction. One patient required a second stage operation for excision of an extension of disease deep to the superior semicircular canal via the middle cranial fossa approach in order to preserve cochlear function. These five cases illustrate the diagnostic pitfalls of this condition in which silent danger lurks behind an intact tympanic membrane.

Blood loss and transfusion in head and neck tumour surgery.

Major head and neck surgical procedures at the Department of Otolaryngology, Singapore General Hospital during a two year period were reviewed. Sixty-three patients were available for study. Data obtained included tumour site and stage, surgical procedure, duration of operation, preoperative haemoglobin and haematocrit, estimated surgical blood loss, amount of blood ordered and used. Data were grouped by procedure. Temporal bone resections showed the highest average estimate of blood loss (1203 mL) and the highest average blood use (3.0 units), followed by composite resections (1067 mL and 2.3 units) and maxillectomy/midface procedures (616 mL and 1.4 units). The degree of blood loss showed a positive correlation with the duration of operative procedure. The majority of patients (62%) met all criteria to qualify as autologous blood donors making autologous transfusion a feasible option for these patients.

Prognostic factors in idiopathic sudden hearing loss.

A retrospective study of 60 cases of idiopathic sudden hearing loss admitted to the Department of Otolaryngology, Singapore General Hospital over a five year period was carried out. The age ranged from 16 years to 74 years. No racial predisposition was found. All cases were treated as an otological emergency and managed as inpatients. All were treated with high dose steroids. Fifty-five percent recovered their hearing significantly. Several factors associated with poorer recovery of hearing were found: severity of hearing loss; high tone loss; longer time from onset to initial audiogram; hypofunctioning vestibular organ and age older than 60 years and under 19 years.

A study on the prevalence of hepatitis B surface antigen among Chinese adult males in Singapore.

A study was conducted in Singapore on 8829 Chinese men aged 35 years or more to determine whether the prevalence of hepatitis B surface antigen (HBsAg) positivity is associated with the source from which the subjects were recruited, or with occupation as an indicator of socioeconomic status. The HBsAg prevalence rates were significantly different (p less than 0.0001) among the five source groups: 8.3% in healthy blood donors, 7.8 in other healthy subjects, 9.2 in non-hepatic outpatients, 10.3 in hospital non-hepatic patients who were not gravely ill, and 11.2 in hospital non-hepatic patients who were gravely ill. After statistical adjustment by multiple logistic regression for age and occupation, the odds ratio (using 'other healthy subjects' as the reference group) ranged from 0.98 (95% CL = 0.65-1.47) for healthy blood donors to 1.42 (95% CL = 0.95-2.12) for hospital non-hepatic patients who were gravely ill. The HBsAg prevalence rates were also significantly different (p less than 0.0001) among occupations: 8.5% in professional, technical and administrative personnel, 9.7 in clerical, sales and services personnel, 10.3 in agricultural and factory workers and unskilled labourers, and 10.5 among the unemployed and retired. After statistical adjustment for age and source groups, the odds ratio (using professional, technical and administrative subjects as the reference group) ranged from 1.07 (95% CL = 0.99-1.17) for the unemployed and retired subjects, to 1.19 (95% CL = 0.93-1.53) for agricultural and factory workers and unskilled labourers.

A preliminary study of the health of a populaltion staying in apartments of varying sizes in Singapore.

A study was made of the health of 438 households living in high-rise flats in three public housing estates in Singapore. These households were selected by serial sampling from a total sample of 594 households; 156 (26%) were non-respondents. The study used personal interviews to collect data. Respondents questioned directly indicated a low but positive effect of high-rise living conditions on their physical health. The perceived health status of most of these flat dwellers remained unchanged after moving into their present accomodation. The major findings with regard to mental health were: (a) worry and anxiety were associated with the socio-economic status of the respondents; (b) the recreational activities of the respondents were related to their socio-economic status, although the majority spent most of their spare time at home; (c) living conditions in flats tended to affect the patterns of social contacts of the residents with their extended families and primary groups. Three factors (income, education and ethnic group) affected the social behaviour of the respondents with regard to health: (a) the preference for, and selection of, the first source of medical treatment varied for the different soci-economic and ethnic groups; (b) self-medication was associated with ethnic group; (c) the level of education affected the decision on when to receive antenatal care.