Medical examiner variability.

There are undoubtedly many factors that contribute to inter-examiner variability relevant to the use of medical practitioners in justiciable matters. One source of variability with regard to claims relating to hearing disorders could well be the training and 'calibration' of medical examiners. A tentative analysis of the examination papers and of the declared roles of the specialties that provide these examiners lends support to such a thesis. One solution would be to train special specialists for medicolegal work, as envisaged by Boyarsky for forensic urology (Boyarsky, 1996). At the same time there is the need to change the role-perception of many examiners. There is also the need for medical examiners to express honest, unbiased opinions. There are also problems inherent in the litigation process which does not promote the interactive and adaptive processes between experts that characterise scientific discussions and enquiry.

Calcium and magnesium mass transfer in peritoneal dialysis patients using 1.25 mmol/L calcium, 0.25 mmol/L magnesium dialysis fluid.

OBJECTIVE: To examine the effect of a reduced calcium/magnesium dialysis fluid (1.25/0.25 mmol/L, respectively) on calcium and magnesium mass transfer in both 1.36% and 3.86% glucose solutions. DESIGN: Each patient underwent four test exchanges, two with a standard dialysis fluid containing 1.36% and 3.86% glucose, and two with a reduced calcium/magnesium fluid containing 1.36% and 3.86% glucose. Calcium and magnesium were measured in dialysate and serum at 0 and 240 minutes. SETTING: Single renal unit of a university teaching hospital. PATIENTS: Sixteen patients established on CAPD, and peritonitis-free, for at least 3 months. RESULTS: A lower dialysate calcium results in negative mass transfer when serum-ionized calcium exceeds dialysate calcium (mean -0.21 +/- 0.15 mmol/exchange), and positive mass transfer when serum-ionized calcium is less than dialysate calcium in 1.36% glucose solutions (mean 0.57 +/- 0.18 mmol/exchange). A negative correlation was found between serum-ionized calcium level and calcium mass transfer. With a 3.86% reduced calcium/magnesium solution, calcium mass transfer is always negative (-0.88 +/- 0.18 mmol/exchange) due to ultrafiltration and solute drag. Fifteen patients were found to be hypermagnesemic at the time of the study. Magnesium mass transfer was neutral with the standard 1.36% glucose fluid (mean -0.01 mmol/exchange), but negative with the reduced calcium/magnesium 1.36% glucose fluid (mean -0.58 +/- 0.13 mmol/exchange). With the 3.86% glucose solution, both fluids produced negative magnesium mass transfer (mean -0.32 +/- 0.11 and -1.07 +/- 0.11 mmol/exchange for standard and reduced calcium/magnesium fluids, respectively). CONCLUSIONS: We conclude that this fluid formulation should reduce hypercalcemia and hypermagnesemia in CAPD patients.

[Hypoacusis and tinnitus: an overview]. / Hypoacousies et bourdonnements: une perspective globale.

An overview of hearing loss and tinnitus deals with the evaluation and measurement of auditory function and the factors which influence hearing. The change in the threshold of hearing with age shows a basic pattern, which is also observed in many auditory disorders. Characteristically, the audiogram is bisegmental, with change in threshold being a linear function of log frequency.

Occupational noise induced vestibular malfunction?

This paper comprises a review of the evidence for the possibility that exposure to noise may damage the vestibular receptors in the internal ear as well as those in the cochlea. The review covers lay and medical publications, observations on patients, experimental studies, and compensation claims. It concludes that the verdict must be "not proven"--that is, although such damage is possible, the evidence is not strong enough to regard it as probable.

The influence of contralateral acoustic stimulation on click-evoked otoacoustic emissions in humans.

Contralateral acoustic stimulation has the effect of reducing the amplitude and shifting the phase of click-evoked OAEs. This effect is thought to be mediated via the medial efferent system and, therefore, the presence of this effect could be used to test the integrity of the neural pathway from one cochlea to the other. With a clinical application in mind, a technique for demonstrating the influence of contralateral acoustic stimulation on click-evoked OAEs was designed to overcome fluctuations in patient and environmental noise. The results of this test on three normal subjects and a patient with a posterior fossa lesion are described.

The prevalence of psychological disturbance in neurotology outpatients.

This study assesses the prevalence of psychological disturbance among a consecutive series of 120 neuro-otology outpatients, using a structured interview conducted by a clinical psychologist. 42% of all patients were found to be in need of, and were offered, psychological help (27% of those with hearing loss, 45% of those with tinnitus and 64% of those with dizziness). 86% of those offered psychological help accepted it. Current psychological distress was associated with the number of symptoms complained of and past psychiatric history. Patients completed the General Health Questionnaire which was found to have a sensitivity rate of 82% and a specificity rate of 87% in this setting. Physicians were also asked to rate patients' psychological state; close agreement was found between these ratings and those of a psychologist. The contribution of psychological assessment of neuro-otology patients is discussed.

Emotional stability; its relationship to confidence in maintaining balance.

Previous failures to find an association between postural test results and the complaints of dizziness/imbalance were further investigated in neuro-otology out-patients, testing in a range of everyday situations requiring balance. Three matched groups of patients were compared: those complaining of dizziness/imbalance; those reporting but not complaining of dizziness/imbalance; and those who had never experienced these symptoms as noteworthy. No difference was found between the groups in measures of postural performance, self-reported confidence in balance, or in several trait measures of fear/anxiety. However, confidence in balance was significantly correlated with fear/anxiety measures across the sample. The correlations were strongest in complaining patients and weakest in patients reporting but not complaining of dizziness/imbalance. The results suggest that psychological characteristics are likely to influence the reporting of symptoms of dizziness/imbalance. The contribution of vestibular and other balance disorders is unclear given that the three groups performed equally well on postural tests.

The age function of hearing--aspects of the epidemiology.

This paper gives a general perspective of age changes in hearing thresholds and reviews possible mechanisms for these age-associated hearing losses. Ways in which new technologies might be able, either now or in the foreseeable future, to determine to what extent the various structurally demonstrable age changes are responsible for these measured losses are suggested. It is hoped that, eventually, the extent to which deteriorations in these various structural components of the auditory system contribute to the ageing process in hearing will be quantified.

Evaluation of a computer interview system for use with neuro-otology patients.

The effectiveness, feasibility and credibility of a computer assessment package was evaluated in a group of 60 neuro-otological outpatients. The computer system was compared with a standard questionnaire and used to elicit basic neuro-otological information prior to clinical interview. The majority of patients (81%) preferred computer assessment. There were no differences in attitude or difficulties between diagnostic groups. Older patients had more difficulties and took longer than younger patients. The computer system was also more efficient than the form from an information handling and administrative point of view.

Dizziness and perceptual style.

This study tested the hypothesis that patients suffering from non-organic ('psychogenic') dizziness would score higher on Witkins' frame dependence test than a group of dizzy patients with peripheral organic damage. A computerized version of the portable rod and frame test was administered to a group of 10 chronic ENT patients with peripheral vestibular disease, 10 ENT patients with no detectable organic problems and 10 non-dizzy controls. Contrary to the hypothesis, the psychogenic group had less frame-dependent error than the peripheral group and less (though not significantly so) than the normal group. Four of the psychogenic group had very low frame dependence scores. The experience of dizziness may not be necessarily related to anxiety proneness and may be a function of an inhibitory autonomous perceptual style as well as one overly dependent on external cues.

Cognitive variables in tinnitus annoyance.

Two new questionnaires were devised to investigate dimensions of complaint about tinnitus. Following a factor analysis of data provided by a sample of tinnitus patients who were administered the first questionnaire, the second questionnaire was developed. This included questions concerning coping attitudes and beliefs about tinnitus. The results of the two analyses were similar and they indicated the presence of three main dimensions of complaint (emotional distress, auditory perceptual difficulties, and sleep disturbance). However several smaller factors suggested that complaint was more complex than originally predicted. The second questionnaire successfully discriminated complaining from non-complaining patients.