Investigating the risk factors of vestibular dysfunction and the relationship with presbyacusis in Singapore.

OBJECTIVES: This study aimed to determine the prevalence of vestibular dysfunction in the Singaporean elderly and its association with presbyacusis, age and other associated risk factors. METHODS: A cross-sectional study was undertaken in a tertiary otorhinolaryngology department and the community. Healthy adults aged 40 years and above who participated in the institution's community presbyacusis screening programme were invited to participate. The main outcome measures including pure tone audiometry and vestibular assessment were obtained using a modified Clinical Test of Sensory Interaction on Balance. RESULTS: The prevalence of vestibular dysfunction and presbyacusis in the study population of 216 participants was 30.1 per cent (95 per cent confidence interval, 24.0 to 36.2 per cent) and 55.6 per cent (95 per cent confidence interval, 49.0 to 62.2 per cent), respectively. The median age was 60 years (range, 40-86 years). The adjusted odds ratio for vestibular dysfunction increased by 6.2 per cent with every year of life (p 0.05). CONCLUSION: Vestibular dysfunction is independently associated with ageing and presbyacusis. Further research into the benefits of additional screening for vestibular dysfunction in elderly presbyacusis patients is warranted.

Quality of life in patients with untreated age-related hearing loss.

BACKGROUND: Hearing loss commonly affects quality of life in the elderly, yet is often neglected. OBJECTIVES: To investigate the impact of untreated age-related hearing loss on the quality of life of elderly individuals, and to assess the usefulness of quality of life questionnaires as screening tools for significant hearing loss. METHODS: We recruited 80 patients aged 50 years or more with untreated hearing impairment. The Short Form 36 Health Survey and the Hearing Handicap Inventory for the Elderly Screening Version questionnaire were administered. RESULTS: There was no significant association between severity of hearing impairment and Short Form 36 Health Survey scores. However, dose-graded correlation was observed between severity of hearing loss and Hearing Handicap Inventory for the Elderly Screening Version questionnaire scores (p < 0.001). A score for the latter questionnaire of more than 8 was 72.8 per cent sensitive and 71.4 per cent specific in detecting clinically significant hearing loss of at least 40 dB (receiver operating characteristic = 0.83). CONCLUSION: The Short Form 36 Health Survey, a generic measure, lacked specificity and sensitivity in detecting clinically significant hearing loss. However, significant hearing impairment was reflected in the Hearing Handicap Inventory for the Elderly Screening Version questionnaire scores, suggesting that this is a good, disease-specific screening tool. A combination of functional (i.e. the Hearing Handicap Inventory for the Elderly Screening Version questionnaire) and physiological (i.e. audiometric) assessment is recommended to investigate hearing loss in elderly individuals.

Coupling of ab initio density functional theory and molecular dynamics for the multiscale modeling of carbon nanotubes.

A multiscale technique is developed that couples empirical molecular dynamics (MD) and ab initio density functional theory (DFT). An overlap handshaking region between the empirical MD and ab initio DFT regions is formulated and the interaction forces between the carbon atoms are calculated based on the second-generation reactive empirical bond order potential, the long-range Lennard-Jones potential as well as the quantum-mechanical DFT derived forces. A density of point algorithm is also developed to track all interatomic distances in the system, and to activate and establish the DFT and handshaking regions. Through parallel computing, this multiscale method is used here to study the dynamic behavior of single-walled carbon nanotubes (SWCNTs) under asymmetrical axial compression. The detection of sideways buckling due to the asymmetrical axial compression is reported and discussed. It is noted from this study on SWCNTs that the MD results may be stiffer compared to those with electron density considerations, i.e. first-principle ab initio methods.

Why generic and disease-specific quality-of-life instruments should be used together for the evaluation of patients with persistent allergic rhinitis.

BACKGROUND: The importance of assessing health-related quality of life (HRQL) of patients with allergic rhinitis (AR) has been well established, but the specific roles of rhinitis-specific or general health instruments have not been delineated. OBJECTIVE: We analysed the psychometric properties of a disease-specific instrument, the Rhinoconjunctivitis Quality-of-Life Questionnaire (RQLQ) and the general health instrument, the Medical Outcome Short-Form 36 (SF-36) as they are employed in combination in patients with persistent AR in clinical practice. METHOD: We analysed the data collected from a prospective study of 43 newly diagnosed patients with persistent AR and 44 controls. We interviewed the patients four times, at baseline, weeks 4, 8 and 10. RESULTS: The RQLQ and SF-36 have good discriminative property, internal consistency, and test-retest reliability. The RQLQ is superior to the SF-36 as an evaluative instrument because more of its domains respond to change, the magnitude of change was greater, and the response was faster. The SF-36 is more susceptible to floor and ceiling effects. Both instruments are unsuitable for mildly symptomatic patients based on Rasch model analysis. Each questionnaire assesses a distinct and significant portion of the total HRQL of persistent AR. CONCLUSION: The SF-36 and RQLQ are good for discriminating rhinitis patients from controls, but the former is poor for detecting changes in QOL. Both are inappropriate for mildly symptomatic patients. Each instrument measures non-overlapping halves of the measurable HRQL. For an assessment of the HRQL in persistent AR that is complete and responsive both instruments should be employed together.

Management dilemmas in laryngeal trauma.

Laryngeal trauma is an uncommon injury. This has made it difficult for a common management pathway to evolve and controversies remain. Methods of airway control, usage of investigations and the role of stents or plates in surgical management are reviewed. It is important not to delay treatment due to the poor voice and airway outcome of chronic laryngeal stenosis.

An audit of endoscopic sinus surgery.

AIM OF STUDY: A prospective study was carried out to evaluate the results of endoscopic sinus surgery based on symptom score and endoscopic findings and to evaluate the prognostic factors using an audit form designed by IS Mackay of London. METHODS: Consecutive cases undergoing endoscopic sinus surgery were entered into the study. Pre-operative symptom, computer tomographic and endoscopic scores were recorded. Operations were also evaluated objectively; post-operative symptom and endoscopic scores were recorded at 3, 6 and 12 months. Cases lost to follow-up were interviewed over the telephone and offered free endoscopic assessments. Those who required revision surgery were considered failures and re-entered into the study. RESULTS: The study comprised 113 cases (108 patients, 60 males and 48 females) with ages ranging from 14 to 80 years (mean 40.4). There were 52 with chronic rhinosinusitis, 46 with nasal polyps, 7 with tumours/inverted papillomata, 5 with acute complicated sinusitis and 3 with fungal sinusitis. Of these, 81.9% of patients with chronic rhinosinusitis or polyps showed an overall improvement of symptoms. Nasal obstruction showed the greatest improvement, followed by rhinorrhoea, loss of smell and headaches and facial pain. Endoscopic improvement was greatest in polyps (83.3%) and oedema (87.0%) but less for discharge (59.4%). CONCLUSIONS: Our results compared well with international series. Computer tomography scoring and the number of revision operations emerged as potential prognostic indicators requiring further evaluation.

Quality of life of patients with perennial allergic rhinitis: preliminary validation of the Rhinoconjunctivitis Quality of Life Questionnaire in Singapore.

Though sufferers of perennial allergic rhinitis do not die from their ailment, they endure years of chronic nose disease that Interferes with many important aspects of their lives. A rhinitis-specific instrument to gauge the quality of life of patients with this disease was published in 1991. Here, we validated the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) for use in English-speaking patients with perennial allergic rhinitis. We established that the RQLQ distinguishes between patients and control, demonstrates internal consistency and is sensitive to change. This study suggests that the RQLQ can be used to assess the quality of life of patients with perennial allergic rhinitis in Singapore.