French Society of ENT (SFORL) guidelines (short version): Audiometry in adults and children.

INTRODUCTION: French Society of ENT (SFORL) good practice guidelines for audiometric examination in adults and children. METHODS: A multidisciplinary working group performed a review of the scientific literature. Guidelines were drawn up, reviewed by an independent reading group, and finalized in a consensus meeting. RESULTS: Audiometry should be performed in an acoustically controlled environment (<30dBA); audiometer calibration should be regularly checked; and patient-specific masking rules should be systematically applied. It should be ensured that masking is not overmasking. Adult pure-tone audiometry data should be interpreted taking account of clinical data, speech audiometry and impedancemetry. In case of discrepancies between clinical and pure-tone and speech audiometry data, objective auditory tests should be perform. In children aged 2 years or younger, subjective audiometry should be associated to behavioral audiometry adapted to the child's age. In suspected hearing impairment, behavioral audiometry should be systematically supplemented by objective hearing tests to determine and confirm the level and type of hearing impairment.

Intra-individual variability in tinnitus patients : current thoughts and perspectives.

Most tinnitus studies have attempted to compare groups of individuals, thus revealing inter-individuals differences, i.e., variations between compared subjects. For methodological reasons, inter-individual studies cannot take into account the variability of tinnitus experience, which has been known for decades to be relevant in daily practice with tinnitus patients. The concept of intra-individual variability has been promoted in the research literature, in order to shed light on this aspect of individual perception. In previous studies, unrelated to hearing, the concept of intra-individual variability implied inclusion of the environment (i.e., physical and social interactions) as a factor of individual performance. In tinnitus research, we believe that the concept of variability (within a person) could find a place beside the concept of variation (between groups of subjects). In this paper, four perspectives of tinnitus experiences from the clinical and research fields are described: (1) ENT consultation; (2) short-term group psychotherapy; (3) psychodynamic psychotherapy; and (4) clinical psychological research. Intra-individual variability stresses the importance of defining tinnitus in a dynamic way, contrary to the current definition of tinnitus as the perception of sound(s). In clinical practice, it is useful to embrace the perspective of the perceiver of tinnitus, and to include social and cultural circumstances as well as audiological/physical changes.

Bone conduction: an explanation for this phenomenon comprising complex mechanisms.

Bone conduction hearing inevitably involves vibration of the basilar membrane in response to a pressure gradient on either side of the membrane. The propagated wave that symbolizes this vibration of the basilar membrane can be triggered intentionally, when a bone vibrator is placed on the mastoid bone, or inadvertently when testing hearing of one ear by air conduction while disregarding transmission of the sound to the other side. When hearing is tested with a bone vibrator, the pathways leading to the basilar membrane can be divided into two main categories. The first type of pathway short-circuits the middle ear and comprises three distinct mechanisms: cochlear fluid inertia, compression of the cochlear walls, and pressure changes exerted via cerebrospinal fluid. In the second type of pathway, the stimulus reaches the basilar membrane via the middle ear, either directly or via the outer ear. Although it is difficult to precisely determine the contribution of each of these pathways to the basilar membrane, bone conduction remains the clinically most reliable way of directly testing cochlear function.

[Tinnitus and deafness]. / Acouphènes et surdité.

The relationships between tinnitus and hearing loss are studied from a clinical prospect. Five critical points are discussed. 1. Some degree of hearing loss is found in the vast majority of tinnitus patients; but an individual may well have a sensorineural hearing loss and no tinnitus at all. 2. A minor adjunction to the neurophysiological model of Jastreboff is proposed to take account of the association between tinnitus and hearing loss. 3. Tinnitus appears to cause more distress when hearing loss is marked. 4. Self-reported hearing loss should be considered when implementing habituation sound therapy. 5. According to McKinney, the rate of success on tinnitus that can be expected with habituation sound therapy is not significantly affected by hearing level.

Long-term outcome of childhood hearing deficiency.

This report is based on the questionnaire responses of 95 young hearing-impaired adults (39 with moderate, 20 with severe and 36 with profound hearing loss) who were investigated in the department of paediatric audiology during childhood. Half of the individuals were educated in ordinary school (integration) and half in an institution for hearing-impaired children. Responses on social and professional insertion were compared with audiometric threshold and educational setting. Results indicate that both hearing level and educational environment influence current mode of communication and use of hearing aids. Familial factors also seem to have an influence. Oral communication is a poor predictor of employment, whereas professional qualifications enhance the chances of finding a job. Obtaining a non-professional degree appears to be unsuited for improving the employment rate of the hearing-impaired child.

[Multi-frequency tympanometry in experimentally-induced cochlear lesions in chinchillas and guinea pigs]. / Données de l'impédancemétrie multifréquentielle dans les pathologies cochléaires. Approche expérimentale chez le chinchilla et le cobaye.

OBJECTIVES: To establish that susceptance-conductance tympanograms at a probe-tone frequency of 2 kHz reflects the status of the annular ligament (AL) and through it of the cochlea. METHODS: Experimental study in 5 chinchillas and 22 guinea pigs. Six validating experiments were used: blockages of the stapes and of the round window membrane (RWM), fistula of the RWM, fluid removal from the cochlea, injection of saline in the scala tympani (ST) and acoustic trauma (AT). Quantitative data (mean values of Y226, FR, Y2000, G2000 and B2000) and shape of the curves were analyzed before and immediately after lesions were done. RESULTS: Guinea pig was the most convenient provided bulla was vented and the same tip was used along the experiments. Only the shape of the curves are discriminant: 1/a supplementary sharp peak, centered around negative pressures, is observed in Y/G tympanograms in every case of RWM fistulas and in some case of AT. 2/injection of saline into ST induces immediate and reproducible Y2000, G2000, et B2000 curves modifications. 3/RWM and stapes blockages provoke foreseeable stiffening and sharpening of the tympanograms at 2 kHz. 4/on the contrary, fluid removal from the cochlea induces multiple peaks curves. CONCLUSIONS: Experimentally-induced modifications at the AL either direct (stapes blockage) or indirect by AT or decrease/increase of pressure load at the cochlear interface at the footplate result in noticeable, constant, reproducible changes of curves registered at 2 kHz. The stapes behaves both as the plotter of the curves and the interpreter of the inner ear pressure.

[Multi-frequency impedance measurement and Meniere's disease. Analysis of the results of TEFLAG]. / Impédancemétrie multifréquentielle et maladie de Ménière. Analyse des résultats du TEFLAG.

We present today our preliminary results of the TEFLAG test performed on 58 patients suffering from Meniere's disease. This test completed in 1993 has already led to a 4-stage classification of noise induced hearing losses. On the one hand, it is based on the morphological study of susceptance B curves, and on the other hand, on the study of the resonant frequency (RF) of the annular ligament of the stapes, provided by a multifrequential impedancemeter. The endolymphatic hydrops coming with the Meniere's disease practically always cohabits in the intercritical period with the decrease of the perilymphatic pressure of the scala vestibuli, which is shown in the morphology of Stage IV curves especially, and the decrease of the annular ligament rigidity. Inversely, during the vertigo or around, we mainly have stage I curves, and an increase of the stapes annular ligament resonant frequency (RF), testifying the labyrinthic hydrops, which is the physiopathological essence of the Meniere's disease.

Short-term effectiveness of medial efferents does not predict susceptibility to temporary threshold shift in the guinea pig.

The 2f1-f2 distorsion product (DPOAE) was measured in conjunction with contralateral noise to evaluate the short-term effectiveness of the olivocochlear efferents in guinea pigs (GPs). An attenuation effect was observed predominantly between 1 and 6 kHz when primary tones were set at 65 dB SPL (contralateral noise of 55 dB SPL). Subsequently, GPs were exposed to a 2 kHz tone of 87 dB SPL for 40 min, using DPOAEs as an estimate of cochlear sensitivity. The response of the cochlea appeared variable. In order to investigate whether effectiveness of efferents plays a role in temporary threshold shift (TTS), the responses of the cochlea to overstimulation were classified into three groups: i) clear cochlear change with complete recovery or actual TTS (group A1); ii) clear cochlear change with incomplete recovery (group A2); iii) mild or no change in cochlear function (group B). No relationship was found between the attenuation effect measured before noise overexposure and the susceptibility to TTS. Animals with a significant attenuation effect could fit into any of the three groups. In addition, the recovery from loud sound exposure was not paralleled with the changes occurring over time in the attenuation effect. Therefore, the conclusion that short-term effectiveness of medial efferents does not predict susceptibility to TTS in the GP is suggested.

Development of capacities of communication and socialization in young deaf children: utility of a common assessment protocol for implanted or hearing aid equipped children.

Pediatric cochlear implantation has attracted a growing interest among health professionals, but it has also encountered opposition on the deaf community. It is therefore incumbent upon the medical teams that carry out this procedure to furnish scientific arguments demonstrating the benefits of this technique for the age group 2 to 4 years and its innocuousness for the child's later psychological development. With this in mind, we have elaborated an assessment protocol adapted to very young deaf children, regardless of whether they have implants or hearing aids. The present report describes two tests of the protocol, chosen because they meet needs which until now have been insufficiently, or not, met. The first of these tests aims at assessing, as early as the age of two, oral and gestual production thanks to sequential images. The second test is the most original element of our psychological protocol: analysis of the child's interactional attitudes through filmed game situations. The initial results from a group of children recently implanted and from another group equipped with hearing aids are presented. These children continue to be seen at regular intervals. It is reasonable to hope that this kind of study will afford objective arguments to the debate in progress.

Intracochlear electrical tinnitus reduction.

Several reports have indicated that some cochlear implant patients experience a reduction in their tinnitus while listening to noise or speech. In the present study, two patients reporting bilateral tinnitus were selected from a group of adults with the Nucleus cochlear implant. They rated their tinnitus loudness and severity and completed the Tinnitus Handicap Questionnaire. The stimuli for electrical stimulation were charge-balanced pulse trains of various repetition rates (frequencies) and inter-electrode distances. A range of electrodes was chosen in each subject, including basal, medial and apical electrodes. For each condition, the hearing threshold level and the uncomfortable loudness level were determined. A range of stimulus levels between these two values were presented randomly. After each presentation, the patients rated the stimulus loudness and the tinnitus loudness on a 0 to 100 scale. These judgements were used to carefully determine the psychometric function between stimulus level and stimulus loudness, and between stimulus level and tinnitus loudness. All the parameters explored were important for maximizing the relationship between tinnitus reduction and stimulus loudness. First, the effectiveness of electrical stimulation in tinnitus reduction depended on the place along the cochlear partition. Second, a pulse rate of 125 Hz showed the greatest efficiency in terms of the current level needed to suppress tinnitus. Third, these two subjects showed rather poor performances in speech perception when using their speech processor in the usual condition and the hypothesis of an influence from tinnitus annoyance is suggested in addition to some more classical predicting factors of speech recognition in cochlear implant users.

[Value of the association of normovolemic dilution and hyperbaric oxygenation in the treatment of sudden deafness. A retrospective study]. / Intérêt de l'association hémodilution normovolémique-oxygénothérapie hyperbare dans le traitement des surdités brusques à partir d'une étude rétrospective.

The multiple treatments of sudden deafness shows how this pathology still remains quite unknown. The authors present a retrospective study of 87 patients treated by normovolemic hemodilution associated to hyperbaric oxygenation. They obtain a total à 60% of significant recovery (ratio between hearing gain and initial hearing loss, above 25%) and in severe hearing loss (threshold between 70 and 90 dB) 60% of good results (ratio above 50%). The importance of the initial form of audiogram and the presence of dizziness as prognostic factors is not confirmed. On the other hand, the evolution of tinnitus is correlated with the deafness and it is a supplementary means to evaluate the therapeutic efficiency. Moreover the persistence of tinnitus represents an important after effect. Sudden deafness still remains a medical emergency and the delay for carrying out any treatment should be as short as possible. On the other hand it is possible to reduce hospital stay by two sessions of hyperbaric oxygenation per day.

[Sudden deafness: a randomized comparative study of 2 administration modalities of hyperbaric oxygenotherapy combined with naftidrofuryl]. / Surdités brusques: étude comparative randomisée de deux modes d'administration de l'oxygénothérapie hyperbare associée au Naftidrofuryl.

Hyperbaric oxygen therapy is one of the numerous therapies which have been proposed in the management of sudden deafness. It is presumptuous to claim the efficiency of any treatment in a pathology where both the origin and the actual rate of spontaneous recovery are unknown. The grounds of therapies are therefore empirical but the need of urgent therapy is dictated by ethics. This study compares the effects of hyperbaric oxygen therapy in two groups of patients; according ot their order in randomization the subjects were treated either at a rate of 1 session or 2 sessions per day. Hyperbaric oxygen therapy was associated with infusion of Naftidrofuryl to counteract the vasoconstrictive effect of increased oxygen pressure in blood. Steroids were also administered simultaneously to avoid, for the same reasons, cerebral oedema. Normovolemic hemodilution (Dauman et al. 1983) was systemically performed in all the patients preliminarily to hyperbaric oxygen therapy, in order to reduce the haematocrit and thus facilitate blood supply. The efficiency and the side effects were similar in the two groups, provided that some principles in the selection and the monitoring of the patients were respected. The rate of 2 sessions of hyperbaric oxygen therapy per day has obvious advantages in view of health policy, but it requires the hospitalization of the patient and should be restricted to the younger subjects.

[Tinnitus: peripheral and central aspects]. / Acouphènes: aspects périphériques et centraux.

Tinnitus is often related to a peripheral impairment which seems to trigger an abnormal autonomous functioning of the central auditory system. Moreover peripheral stimulations may diminish, and even suppress their perception, either through masking or through inhibition of an aberrant neuronal activity. Here we present an experimental model of peripheral deafferentation in which a decrease of neurochemical activity is observed in the brainstem auditory nuclei, followed by a progressive recovery after the peripheral destruction. This activity could represent a central morphofunctional correlate of tinnitus. Development of experimental models of tinnitus must be continued. Such models should allow the study of the basic physiological mechanisms behind tinnitus and suggest some therapeutic approaches which could be objectively evaluated.

Recent Advances in Tinnitus.

Tinnitus can be the most debilitating symptom faced by people with hearing impairments. In the past 10 years, there has been a large increase in tinnitus research and in the development of clinical protocols. New animal models and physiological procedures provide an important contribution to the understanding and measurement of tinnitus. The annoyance of tinnitus likely depends on its loudness and the psychological makeup of the patient. The loudness of a person's tinnitus can be compared with the equivalent loudness of a 1000 Hz tone in a normal ear. Several questionnaires have recently been introduced to quantify the handicap caused by tinnitus. Tinnitus maskers are apparently ineffective for most patients but they can be helpful in a few patients. Medications are largely ineffective in reducing tinnitus in most people. However, several psychological techniques for reducing the stress associated with tinnitus are currently under investigation, and preliminary results show some promise. Tinnitus can be reduced by electrical stimulation in a few patients, and this is also an important area for future research.