The origins of immunology and allergy are founded upon the early 19th century microbiological studies of Jenner and Pasteur. It was discovered that the immune system could cause harm. The subspecialty of allergy began with the coining of the term by Von Pirquet in 1906 to describe disorders resulting from hyper-reaction to normally innocuous environmental agents.

Understanding the scientific basis of the immune system and allergy allowed Noon and Freeman, and later Cooke, to develop allergen immunotherapy. Initially the technique was crude, but with the subsequent key discovery of IgE, more accurate methods of diagnosis (such as the radioallergosorbent test (RAST)) and treatment ensued. The efficacy of specific immunotherapy has been demonstrated by many double-blind trials culminating in the WHO position paper.

DNA recombinant technology has provided detailed molecular understanding of allergic disorders, which has resulted in several novel methods of immunotherapy that are potentially safer and more effective. Use of recombinant allergens, T-cell peptides, DNA vaccination with CpG motifs or plasmid vectors and anti-IgE strategies with monoclonal antibodies are showing promise.

Eleven patients who had been surgically treated from 1988 to 1999 were retrospectively reviewed in order to evaluate the efficacy of ventilation tube insertion and mastoidectomy with, or without, mastoid obliteration for intractable middle-ear cholesterol granuloma. The mean age registered was 17.2 years at the time of surgical treatment. All cases were unilaterally affected. Five ears were treated with simple mastoidectomy coupled with the insertion of a ventilation tube, while six others had additional mastoid obliteration. The hearing prognosis was excellent with an improved post-operative hearing level of 16.5 dB (cf. pre-operative 37.7 dB). However, morphological prognosis revealed two ears had a residual perforated tympanic membrane without otorrhoea after displacement of the ventilation tube. Of the remaining nine ears with intact placement of the ventilation tube, five had dry ears while four had occasional otorrhoea. Although the morphological prognosis was incomplete, treatments involving at least aninsertion of a ventilation tube with thorough mastoidectomy were thought to be necessary.

Myringoplasty is an established procedure. However, the quest is on to improve the results further by studying the different influencing factors, that could possibly affect the outcome. In the present randomized prospective study of one year’s duration, 60 patients having dry, large and subtotal perforations of the tympanic membrane were subjected to myringoplasty, 30 by the overlay technique and 30 by the underlay technique keeping all other influencing factors constant. The graft take-up rate was found to be the same (93.3 per cent) in both techniques but the underlay technique was judged to be better because of its technical ease, better assessment of ossicular chain integrity and mobility, less time consumption (55 minutes vs 90 minutes), earlier healing of graft (four to six weeks vs six to eight weeks), hearing gain in more patients (92.8 per cent vs 57.1 per cent) and fewer minor complications (6.6 per cent vs 33.3 per cent).

Hearing threshold has been measured in a group of patients following cochlear implantation with a Clarion® device for the last eight years. The patients had received either a pre-curved carrier or the Hi-Focus I plus Electrode Positioner System (EPS). The assessment was carried out within the first post-operative week as well as at a later stage, between six and 87 months, post-operatively. Residual hearing thresholds were still measurable early after surgery in 24.5 per cent of the patients, without differences between the two different Clarion® models. However, the number of subjects with measurable hearing dropped to 16.3 per cent as observed when hearing was measured at a later stage, with an equal distribution between the two groups of patients. From this study it has been possible to observe that only a limited number of patients maintain residual hearing after Clarion® cochlear implantation, and that this tends to decrease further over time. Nevertheless, the performance of these patients for speech tests did not appear to be affected by deterioration of the pure-tone auditory threshold.

Little is known of the aetiology, serotypes or susceptibility of the pathogens causing non-resolving otitis media in children receiving care from specialists in private practice in developed or in developing countries. Increased access to antibiotics in the community amongst children receiving such private care in South Africa may be anticipated to lead to levels of resistance similar to those found in countries with similar models of private practice, such as the United States. This study was conducted to determine the aetiology of non-resolving otitis media in South African children receiving private care and to determine the antimicrobial resistance patterns and serotypes of the bacterial isolates.

Middle-ear fluid was cultured from 173 children aged two months to seven years with non-resolving acute otitis media accompanied by persistent pain or fever who were referred to otorhinolaryngologists for drainage of middle-ear fluid within 14 days of the start of symptoms. While 92 per cent of the children had recently received antibiotics and 54 per cent were currently receiving them, bacteria were isolated from 47 children (27 per cent). Streptococcus pneumoniae was the most common pathogen (35), followed by Haemophilus influenzae (nine), Staphylococcus aureus (six), Moraxella catarrhalis (two), Streptococcus pyogenes (two) and Pseudomonas aeruginosa (one). Two isolates were identified in each of eight children. Antimicrobial resistance to one or more antibiotics was found in 33/35 (94 per cent) of the pneumococci isolated, with resistance to penicillin in 86 per cent, resistance to trimethoprim-sulfamethoxazole in 54 per cent and to erythromycin and clindamycin in 69 per cent and 57 per cent, respectively. The pneumococcal serotypes found were 19F (28 per cent), 14 (26 per cent), 23F (23 per cent), 6B (nine per cent), 19A (87 per cent), and four (three per cent). Children with a bacterial pathogen isolated were younger (mean age of 17 months) than children from whom no bacteria were isolated (mean age of 23 months; p = 0.03). Isolation of a pneumococcus was also significantly associated with younger age (mean = 16 months versus 22 months, p = 0.03), the presence of fever (OR = 2.15, p = 0.049), and having one or more prior episodes of otitis media within the six months before tympanocentesis (OR = 7.72, p = 0.03). Almost all pneumococci isolated from non-resolving acute otitis media in this community are antibiotic-resistant and should be considered especially in young children who have failed previous therapy and who have non-resolving pain or fever.

The differences in facial anatomical structures of the major ethnic groups,may also be reflected in nasal resistance. Active anterior rhinomanometry (AAR) is the recommended technique for the objective assessment of nasal airway resistance (NAR). This study comprised of 85 adult Malay subjects. All the subjects had to undergo a primary assessment of relevantsymptoms of nasal disease and nasal examination before undergoing AAR assessment. The mean value of total nasal airway resistance (NAR) was 0.19 Pa/cm3/s (ranged from 0.09 to 0.55Pa/cm3/s) at 75 Pa pressure point and 0.24 Pa/cm3/s ranged from 0.12 to 0.52 Pa/cm3/s) at 150 Pa pressure point. The mean unilateral NARwas 0.46 Pa/cm3/s at a reference pressure of 75 Pa and 0.51 Pa/cm3/s at a reference pressure of 150 Pa. In this study we presented normal values for NAR in healthy Malay adult subjects. AARproves to be a valuable clinical method for recording and quantitating nasal resistance.

The aim of the study presented was to assess the insertion mode and possible intracochlear trauma after implantation of the HiFocus® electrode with positioner in human temporal bones. The study was performed in five freshly frozen temporal bones. The position of electrodes was evaluated using conventional X-ray analysis, rotational tomography and histomorphological analysis. Insertion of the HiFocus® electrode with positioner resulted in considerable trauma to fine cochlear structures including fracture of the osseous spiral lamina, dislocation of the electrode array from the scala tympani into the scala vestibuli and fracture of the modiolus close to the cochleostomy. The implication of the results regarding clinical outcome will be discussed.

Nasal obstruction is a subjective complaint in patients with nasal disease.The ability to quantitate the nasal ventilation dysfunction would be useful for making the appropriate choice of nasal disease management. This cross-sectional study comprised of 200 adult subjects. They underwent assessment of relevant symptoms, nasal examination and investigations before undergoing active anterior rhinomanometry (AAR) assessment. A group of 88 normal subjectsand 112 patients with nasal disease were included. The mean total nasal air resistance (NAR) was significantly higher in patients with nasal disease (0.33 Pa/cm3/s) as compared tonormal subjects (0.24 Pa/cm3/s). There was no significant difference in total NAR between patients with symptoms of nasal obstruction and those without the symptoms (p = 0.42). It is concluded that AAR is a sensitive but not a specific tool for the detection of abnormalities in NAR and it failed to relate to the symptom of nasal obstruction.

Previous studies concerning the microbiology of otitis media with effusion (OME) did not correlate the past use of antimicrobial agents with the recovered organism’s antimicrobial susceptibility. A retrospective analysis of cultures obtained from aspirates of 129 children with OME was performed. The study identified the isolated organisms and determined their susceptibility to the most recently administered antimicrobials. Bacterial growth was noted in 58 (45 per cent) patients. Aerobic organisms only were recovered in 37 aspirates (63 per cent of the culture-positive aspirates); anaerobic bacteria in seven (12 per cent); and mixedaerobic and anaerobic bacteria in 14 (24 per cent). A total of 92 bacterial isolates were recovered, accounting for 1.6 isolates per specimen (1.1 aerobes and 0.5 anaerobes). There were a total of 66 aerobic isolates, including Haemophilus influenzae non type-b (20 isolates), Streptococcus pneumoniae (17), and Staphylococcus spp. (seven). Twenty-six anaerobes were recovered, including Peptostreptococcus spp. and Prevotella spp.(eight each) and Propionibacterium acnes (four). Resistance to the antimicrobial used was found in 60 (65 per cent) isolates, recovered from 41 (71 per cent) of the patients. Of the41 patients in whom resistance was detected, 37 (90 per cent) had been treated within three months of culture and four (10 per cent) had completed treatment more than three months before thecultures were taken (p < 0.01). The highest rate of recovery of resistant organismswas following trimethoprim-sulfamethoxazole (96 per cent), amoxycillin (71 per cent), and azithromycin (56 per cent). Of the patients treated with amoxycillin, H influenzae predominated. S pneumoniae was recovered from four of the seven (57 per cent) after trimethoprim-sulfamethoxazole, four of 14 (29 per cent) following amoxycillin, and three of 11 (27 per cent) after azithromycin. The data illustrate the relationship between resistance to the antimicrobials given to children and their recovery from the middle ear of patients with OME.

The post-operative outcome of hearing, the reconstructed external auditory canal, and the state of the reconstructed middle-ear cavity after canal wall down tympanoplasty with canal and attico-antrum reconstruction was studied in 103 ears with middle-ear cholesteatoma. The reconstructed mastoid cavity was re-aerated in 36.5 per cent of the cases, which was significantly lower than for the epitympanum (63.5 per cent) and tympanic cavity (82.4 per cent). Tympanoplasty was successful in terms of hearing results in 68.9 per cent of all subjects and in 75.4 per cent of the ears having a re-aerated tympanic cavity, which was significantly better than the 38.5 per cent for ears in which the tympanic cavity was not re-aerated. The findings of recurrent cholesteatoma, tympanic atelectasis, and tympanic effusion were observed with significantly (p<0.03) high incidence in ears with no re-aerated space in their reconstructed mastoid cavities. It was revealed that the post-operative outcome of this surgical technique was significantly related to the state of re-aeration of the reconstructed middle-ear cavity.

The aim of this retrospective study was to determine the possible causes of failure of antibiotic therapy in children with acute otitis media (AOM). Thirty-nine samples of middle-ear fluid were obtained by myringotomy from 31 children suffering from AOM, unrelieved by antibiotic therapy administered for over 48 hours. The samples were analysed by the usual microbiological techniques, including cultures, tests for beta-lactamase producing strains and the determination of the minimal inhibitory concentration of penicillin for Streptococcus pneumoniae. In 14 samples, no bacterial strains were detected in the cultures of middle-ear fluid; and in two samples the cultures revealed two strains of bacteria. The bacteria most frequently identified were Haemophilus influenzae, found in 11 samples, and Streptococcus pneumoniae, found in seven samples, of which four produced strains with reduced susceptibility to penicillin. The failure of antibiotic therapy in AOM appears to be related to the increased resistance of Haemophilus influenzae and to the reduced susceptibility of Streptococcus pneumoniae to penicillin. Other factors contributing to the failure of antibiotic therapy in AOM may be the viruses or the bacteria that produce multiple pathogens in the middle ear.

Clinical success of laryngotracheal protheses are constrained by a combination of biocompatible response in the host and a suitable functional rehabilitation. This review considers clinical limits of different materials commonly used in ear, nose and throat surgery and will more particularly focus on titanium, one material recognized to be well tolerated in implantology.

Testing of otoacoustic emissions (OAE) has been successfully applied to study outer hair cell function. We used this methodology to evaluate and compare the effect of topically applied normal saline, and gentamicin- and ciprofloxacin-containing drops into the middle ear of guinea pigs. All three solutions similarly decreased the distortion product OAE (DPOAE) and all three caused an inflammatory reaction in the guinea pig’s middle-ear. OAE failed to detect adequately the ototoxicity of topically administered drops in this animal model because the opening of the bulla affected DPOAE, and both inflamed middle-ear mucosa and osteoneogenesis caused a decrease in DPOAE amplitude.

This is the first report examining the influence of topically used otic drops on inner ear function as demonstrated by OAE.

The transmission of heat to the vestibule during revision stapes surgery with a piston in situ has been studied using a KTP laser in an in vitro model. A type K thermocouple was placed around the medial of each piston tested in a ‘vestibule’ filled with saline. The effect of laser hits on fluoroplastic, fluoroplastic-wire and stainless steel stapes prostheses was investigated. The effect of adding blood to the operative field, of introducing a vein graft to seal the stapedotomy and of vaporizing soft tissue in the oval window were also examined. Greater temperature rises occurred with stainless steel than with the other piston types and smaller rises occurred when there was a vein graft in situ. The maximum temperature rise recorded was 2.6°C. We conclude that the use of the KTP laser to clear soft tissue from the oval window is safe when operated at the power levels recommended by the manufacturer.

Philipp Friedrich Arnold and Ludvig Levin Jacobson were two of the greatest anatomists of the 19th century. Within this paper their backgrounds and their contribution to the development of various aspects of head and neck anatomy are considered.

The ’hygiene hypothesis’ was popularized in the late 1980s to explain the high prevalence of atopic disordersin the developed countries. It links atopic disorders and the lack of early life infections. An association between the two is not novel and dates back to the beginnings of allergy, immunology and microbiology. Allergy and infection have always been closely related and the study ofone has often provided new insights into the pathobiology of the other. Early research into bacterial infections led to the discovery of the human immune system and the concept of allergy. An important relationship exists between parasite infections and the development of atopic disorders.

This review traces the long and intimate historical relationship between infection and allergy.

Otolaryngology is one of the surgical specialities employing high-powered instruments and this study was designed in order to establish whether sound levels at work conform to HSE guidelines. No study to date has measured intra-operative noise levels in ENT operation theatres. A prospective observational study was therefore performed. Sound levels were measured during the use of bone drills for mastoid surgery and microdebriders for endoscopic sinus surgery. A SLM/IS Acos Class I sound level meter calibrated to BS 1259 was employed. A spectrum analysis of drill-generated noise was measured using a calibrated B and K precision sound level meter. Sound levels emitted varied as follows: Large burrs- 72.4 dB (A), medium size; 71.2 dB (A), small sized burrs- 68.8 dB (A) (all values for cutting burrs) and 60.8 dB (A) for diamond burs. With microdebriders, the average sound level was 60.1 dBA. Spectrum analysis revealed that the maximum intensity was at 3.15 kHz, followed by 4 kHz, while the least sound was produced at 40 kHz and 31.5 kHz. Essentially sound produced by drills was between 1.6 kHz and 6.3 kHz. Powered instruments used in ENT surgery are safe and pose no occupational hazard.

We investigated the eustachian tube function and the incidence of alternobaric vertigo (AV) in 29 sport self-contained underwater breathing apparatus (SCUBA) divers with, or without, some possible risk factors for AV. The divers had normal audiological and otoscopic findings at the pre-dive examination. We used the nine-step inflation/deflation tympanometric test and Toynbee test for evaluation of eustachian tube function, and the Valsalva manoeuvre for patency. Information on divers, their history, and their otolaryngologic examination were obtained in the pre-dive examination. Divers performed 1086 dives (mean 37, range: 3–100) during the observation period. Four divers (14 per cent) experienced AV during five dives (0.46 per cent), (one diver experienced AV two times). It was found that having an otitis media history or eustachian tube dysfunction determined with the nine-step inflation/deflation tympanometric test before diving, or difficulty in clearing ears during diving could be important risk factors for AV in sport SCUBA divers (p<.05). Divers with such findings seem to be more prone to AV and should pay rigorous attention to the precautions for prevention of AV.

This was a study of the use of virtual reality modelling language (VRML) for cross-platform interactive three-dimensional (3-D) visualization of high-resolution magnetic resonance (MR) images of the inner ear in the assessment of cochlear implant candidates.

A retrospective case review was made of cochlear implant candidates undergoing pre-operative high-resolution MR studies to determine their suitability for implantation. 3-D visualizations of MR scans of the inner ear structures were created using surface rendering and exported as portable VRML files.

Case studies are presented to illustrate different points of interest. VRML reconstructions aided the interpretation of two-dimensional (2-D) source images in a variety of inner ear abnormalities.

VRML is an internationally recognized standard for cross-platform 3-D visualization that creates a means of providing the implanting surgeon with a portable 3-D representation of the inner ear, aiding interpretation of the complex cross-sectional anatomy of these structures, and guiding selection of patients for implantation as well as implantation technique. The elucidation of the mechanisms behind inner ear malformations can also be aided by detailed imaging studies of the temporal bone, with VRML reconstructions providing an easily interpreted representation of deformities.