ABSTRACT
Ceramic, titanium and platinum guarantee a perfect bio-compatibility for cochlear implants. Moreover the long term efficacy of the electrode nerve interface is obtained thanks to a limited electric current density. Failure risks of implanted electronic are decreased by use of carefully selected components.
Subject(s)
Biocompatible Materials , Cochlear Implants , Electronics, Medical , Risk FactorsSubject(s)
Auditory Perceptual Disorders/etiology , Hearing Disorders/etiology , Noise , Radio , Adolescent , Adult , Child , Humans , Risk FactorsABSTRACT
This analysis examines the definition, origin, category, acoustic and psycho-acoustic properties and the quantitative and qualitative measurements of noise, allowing one to delineate the problems associated with such a disturbance. There are several definitions of sound, depending on the angle at which one considers the phenomenon: social, acoustic, psycho-acoustic or medical. The acoustic aspect determines its physical characteristics; the psycho-acoustic aspect deals specifically with its effect on the human ear. Noise assumes very different aspects: ambient, stable, fluctuating, intermittent, pulsing. It presents a disturbance depending on different factors: intensity, frequency, length of exposure, mode of arrival, evolution in time, acoustic characteristics. Over and above all these is added a factor of personal sensitivity, varying from one individual to another. Measurement of noise is performed with the help of an instrument called a sonometer, which records the level of the acoustic pressure, i.e. intensity. From this point, one can evaluate the magnitude of auditive disturbance, Leq. Measurement of human hearing has also been established. This is called audiometry. It allows one to assess the auditive value by drawing a graph: the audiogram. AFNOR has established a classification of noises to be found related to social life. Two broad categories: indoor noises, related to the activity in an apartment building and within the lives of its inhabitants, and outdoor noises, linked to traffic noise and its different forms, and to economic and social activity and noise produced by recreational pursuits.
Subject(s)
Noise/adverse effects , Audiometry , Classification , Hearing Loss, Noise-Induced , Humans , PsychoacousticsSubject(s)
Deafness , Social Problems , Combined Modality Therapy , Deafness/epidemiology , Deafness/therapy , France , HumansABSTRACT
112 cases of vestibular neuritis were studied. 77% were relatively pure lesions, whilst in 23% of cases there were more extensive lesions with abnormalities of the saccadic oculomotor system and BERA abnormalities. Spontaneous nystagmus disappeared in 2 to 3 months in general. In 54% of cases there was complete recovery of absolute reflex activity within normal limits on the affected side. There was restoration of normal difference of reflectivity in 22%. In 13% there was normal absolute reflex activity, normal hypovalence and normal directional preponderance. Age appeared to influence the course of directional preponderance and the extent of lesions on the course of hypovalence. Early mobilisation of the patient is of primordial importance.
Subject(s)
Neuritis/diagnosis , Vestibular Nerve , Acoustic Impedance Tests , Adolescent , Adult , Aged , Audiometry, Evoked Response , Child , Electronystagmography , Herpes Zoster , Humans , Middle Aged , Neuritis/etiology , Neuritis/physiopathology , Saccades , Vestibular Function Tests , Vestibular Nerve/physiopathologyABSTRACT
The delay between the stimulus and the voluntary eye saccade is the only parameter of the saccadic system which can be measured by using standard apparatus. Taking manually the measurements made on records obtained by using minicomputer; the authors show that such manual measurement of latencies is easy and yet sufficiently accurate to be of great clinical value. The latencies of voluntary saccades are normal in peripheral pathology (less than 250 milliseconds). Latencies of voluntary saccades are significantly increased in extrinsic brain stem lesions: tumours (in particular ponto cerebellar tumours), meningitis, head injury; but the velocity of the saccade is normal. This effect goes in parallel with impairement of the smooth pursuit. In intrinsic brain stem lesions (multiple sclerosis, acute brain stem stroke, oculomotor paralysis) latencies are increased bilaterally and above all, there is a significant slowing of the saccade. The role of fatigue increased latencies in some patients of this series. Two populations can be discerned in vestibular neuritis: one normal and one with abnormal smooth pursuit and increased saccadic latencies.
Subject(s)
Brain Diseases/physiopathology , Eye Movements , Labyrinth Diseases/physiopathology , Saccades , Brain Injuries/physiopathology , Brain Neoplasms/physiopathology , Brain Stem , Electronystagmography/methods , Female , Humans , Male , Meningitis/physiopathology , Minicomputers , Ophthalmoplegia/physiopathologySubject(s)
Nystagmus, Pathologic/physiopathology , Adolescent , Adult , Aged , Caloric Tests , Child , Child, Preschool , Electronystagmography , Female , Humans , Male , Middle Aged , Nystagmus, Pathologic/etiologyABSTRACT
Two main types of utilisation of microcomputers in otorhinolaryngology are envisaged: instrumentation and medical audit. The modes of employ of the material in these fields are briefly exposed, followed by the presentation of several examples of its employ and functioning. Practical notions are discussed, particular emphasis then being placed on theoretical considerations involved in the use of such equipment. Of primary importance are strictly medical reflections, problem solving being facilitated (by suppressing or diminishing routine tasks) but never simplified.
Subject(s)
Computers , Microcomputers , Otolaryngology/instrumentation , Costs and Cost Analysis , Epidemiologic Methods , Forms and Records Control , Medical Records , Statistics as TopicSubject(s)
Communication , Deafness/psychology , Adolescent , Adult , Aged , Child , Developmental Disabilities/etiology , Humans , Middle Aged , Social IsolationABSTRACT
Nasal response to a large number of stimuli is almost invariably the same, with sneezing, watery rhinorrhoea and nasal obstruction constituting the three major conventional symptoms of the so-called vasomotor (autonomic) rhinitis. These symptoms are not specific to allergic reactions but can be seen in viral infections, sudden changes in temperature, inhalation of irritant fumes or of certain smells. The aetiological diagnosis of vasomotor rhinitis therefore is sometimes very difficult but seems to be greatly facilitated by intranasal challenge tests associated with anterior rhinomanometry.
Subject(s)
Nasal Provocation Tests/methods , Nose/physiopathology , Rhinitis, Vasomotor/etiology , Allergens/administration & dosage , Bronchial Provocation Tests , Humans , Immunoglobulin E/analysis , Manometry/methods , Rhinitis, Allergic, Perennial/diagnosis , Rhinitis, Allergic, Seasonal/diagnosis , Skin TestsABSTRACT
Acoustic neurinomas must be diagnosed as early as possible for the tumour to be removed while it is still small and the facial and, sometimes, auditory functions to be preserved. Since 89% of neurinomas lie on the vestibular nerve, enhancing the sensitivity of test exploring this nerve is important. Bilateral bithermal caloric stimulation is more sensitive (85%) than unilateral stimulation (71%) in detecting functional impairment. By comparing the two examinations in a series of 28 patients the authors have demonstrated that the test is more sensitive and reliable when bilateral and unilateral stimulation are practised successively. A study of correlations between these tests and the volume of the neurinoma showed that while functional impairment generally increases with the size of the tumour, it may vary from nil to 100% in small neurinomas. However, the sensitivity of the caloric test remains inferior to that of more sophisticated audiometric techniques, such as BERA-recording of stapedial reflex.
Subject(s)
Caloric Tests/methods , Neuroma, Acoustic/diagnosis , Vestibular Function Tests/methods , Adolescent , Adult , Aged , Audiometry , Child , Humans , Middle Aged , Neuroma, Acoustic/pathology , Nystagmus, Pathologic/diagnosis , Reflex, Acoustic , Time Factors , Vestibular Nerve/physiopathologyABSTRACT
The perverted nystagmus is a modification of the horizontal beating nystagmus (in classical caloric stimulation) by a vertical or rotatory mainly component. Experimentally, this disorder can be shown after an unilateral destroy of the superior or median vestibular nucleus. We show 32 cases of subjects with a perverted nystagmus. 75% of these subjects have a pure central disease and 20% a vestibular neuronitis. The perverted nystagmus had an upbeat component with the cold stimulation and downbeat component with the hot stimulation. It was accompanied by a spontaneous nystagmus in 66% (and 30% with vertical nystagmus). Some abnormal responses with the simultaneous bilateral vestibular caloric testing, were found in 95%. The analysis of the results of the unilateral caloric testing shown the frequent association: hyporeflectia (canal paresis) of one side and hyper-reflects of the other side. This fact would have evoked a mixed disease, peripheric and central (i.e. the vestibular neuronitis). Beside some pathogenic hypothesis, we prefer the fall of the inhibiting control of the superior semi-circular canal firing activity. Although, the perverted nystagmus is a simple and precious examination sign (it is directly shown with Frenzel glasses after caloric vestibular stimulation. It ought to do the brain stem topography diagnosis.
Subject(s)
Caloric Tests/methods , Eye Movements , Nystagmus, Pathologic/diagnosis , Vestibular Function Tests/methods , Adult , Female , Humans , Male , Meniere Disease/diagnosis , Meniere Disease/etiology , Middle Aged , Nystagmus, Pathologic/etiologyABSTRACT
Vertical nystagmus provoked by simultaneous bilateral caloric stimulation has been known since 1907 (Bàràny). However, if a controlled and calibrated injection os water at 44 degrees C or 30 degrees C for 30 seconds at a flow rate of 250 ml/minute is given in normal subjects, this stimulus is insufficient to provoke a response, whilst in subjects with a central vestibular disorder there appear upward vertical movements with hot stimulation and downward movements with cold stimulation. The degree of this response is proportional to the degree of horizontal nystagmic responses to classical unilateral caloric tests. The authors feel that vertical nystagmic responses to simultaneous bilateral caloric stimulation reflect a loss of control of the vestibular reflex activity of the superior semicircular canals.
Subject(s)
Caloric Tests/methods , Eye Movements , Vestibular Function Tests/methods , Adult , Brain Diseases/diagnosis , Female , Humans , Labyrinth Diseases/diagnosis , Male , Meniere Disease/etiology , Middle Aged , Reflex, Abnormal/diagnosis , Vestibule, Labyrinth/innervationABSTRACT
The effect of bithermal caloric tests on the velocity of spontaneous nystagmus was retrospectively studied in 107 patients with unilateral vestibular areflexia. In 35 out of 107 patients, the velocity or pre-test nystagmus was not lower than 15 jerks in 30 seconds. In our series, spontaneous nystagmus before the caloric test was mostly seen in patients with neuritis or sudden deafness, and as a rule, the tests had little effect on the velocity of the nystagmus. In 7 out of 10 cases of areflexic Mènière's disease spontaneous nystagmus was revealed by caloric tests. Spontaneous pre-test nystagmus was present in 6 out of 29 cases of neurinoma; its velocity was always reduced during the caloric tests. In 14 out of 25 cases of head injury, areflexia was usually compensated. Vestibular compensation can now be defined as the absence of vertigo, of spontaneous nystagmus before and after caloric tests and directional predominance.
Subject(s)
Caloric Tests/methods , Eye Movements , Vestibular Function Tests/methods , Adult , Brain Injuries/diagnosis , Female , Humans , Labyrinth Diseases/diagnosis , Male , Meniere Disease/diagnosis , Middle Aged , Neuritis/diagnosis , Reflex, Abnormal/etiology , Vestibular Nerve/physiopathology , Vestibule, Labyrinth/innervationABSTRACT
The efficacy/tolerance ratio of a new form of betahistidine salt was studied in patients with Ménière's disease or isolated tinnitus. The study was divided into two stages: first, a conventional open trial, then a comparative cross-over trial. Analysis of efficacy scores showed that the drug was clearly effective in relieving vertigo and associated symptoms and had no clinical or biochemical side-effects.
