ABSTRACT
Central vertigo is most often expressed by a feeling of dizziness, non or badly systematized, but it can also appear, more seldom, like an isolated acute vertigo or associated to other neurological signs. A precise clinical exam can lead to evidence essential clinical informations (significant ataxia, neurological signs, gaze nystagmus, pursuit anomaly,...). Almost all acute lesions of central vestibular pathways, as for the peripheral ones, lead to a harmonious vestibular syndrome. The vascular lesion of the vertebro-basilar territory and multiple sclerosis are two main causes to it. The pseudo-labyrinthine forms are essentially described in occlusion infarcts of the AICA and PICA, but a hematoma can lead to the same picture; the diagnostic of multi- or monosymptomatic forms with a peripheral lesion is often very difficult, the classical classification of the central and peripheral vestibular syndromes has become obsolete and should be abandoned.
Subject(s)
Central Nervous System Diseases/complications , Central Nervous System Diseases/diagnosis , Vertigo/etiology , Central Nervous System Diseases/pathology , Cerebellar Diseases/complications , Cerebellar Diseases/diagnosis , Diagnosis, Differential , Humans , Multiple Sclerosis/complications , Multiple Sclerosis/diagnosis , Vertigo/classification , Vertigo/diagnosisABSTRACT
The middle ear forms part of the sound transformer mechanism, together with the outer ear and the conducting system of the inner ear. An intermediate sensory organ, sensitive to acoustic vibration, and linked to the inner ear, the middle ear made its appearance during the period of adaptation of marine creatures to a terrestrial habitat; its presence is therefore a phylogenetic requirement. It is classical to ascribe three functions to the middle ear: the transmission of acoustic vibrations from the tympanic membrane to the cochlea, impedance matching between the air in the external auditary meatus and the labyrinthine fluids, and protection of the inner ear by means of the acoustic reflex. If the classical mechanical explanation has been able to explain its function, the conceptualization of its physiology in terms of energy allows an even better understanding, as well as providing and explanation for the paradoxes which arise in clinical practice when the classical model is used.
Subject(s)
Ear, Middle/anatomy & histology , Ear, Middle/physiology , Humans , Reflex, Acoustic/physiologyABSTRACT
The authors present two cases of genetic deafness in a brother and his sister. The girl has shown to suffer from a deafness belonging to Pendred's syndrome; in this case, the development of hearing symptomatology since her puberty is presented as an aggravated crisis of deafness and tinnitus coinciding with her menstruation, what suggests a possible endolymphatic hydrops depending of hormonal factors; the lack of knowledge about the ethyopatogenic mechanisms in this field generates therapeutic difficulties hard to solve.
Subject(s)
Goiter/complications , Hearing Loss, Sensorineural/genetics , Adolescent , Child , Female , Hearing Loss, Sensorineural/complications , Humans , Male , Perchlorates , SyndromeABSTRACT
We present a group of 50 patients with retrocochlear pathology, divided on 41 (82 per 100) non tumoral and 9 (18 per 100) tumoral: 8 cerebello-pontine angle meningiomas and 1 intracranial cholesteatoma. The retrocochlear diagnosis of the pathology is assessed by the results of the audiovestibular explorations, specially the electrophysiology (early auditory evoked response, electrocochleography). The neuroradiologic explorations (TAC, MNR) define the tumoral or non tumoral nature of the pathology. We review some technical aspects of the common electrocochleographic practice, as actually is realised by the Bordeaux group; also, the different parameters of a retrocochlear pathologic response. In this group, the electrocochleography was necessary on 64 per 100 of the cases to obtain an electrophysiologic retrocochlear diagnostic.
Subject(s)
Audiometry, Evoked Response , Cranial Nerve Diseases/diagnosis , Labyrinth Diseases/diagnosis , Acoustic Impedance Tests , Adult , Audiometry , Cerebellar Neoplasms/complications , Cerebellar Neoplasms/diagnosis , Cerebellar Neoplasms/physiopathology , Cerebellopontine Angle , Cholesteatoma/complications , Cholesteatoma/diagnosis , Cholesteatoma/physiopathology , Cranial Nerve Diseases/etiology , Cranial Nerve Diseases/physiopathology , Electrodiagnosis/methods , Female , Humans , Labyrinth Diseases/etiology , Labyrinth Diseases/physiopathology , Male , Meningioma/complications , Meningioma/diagnosis , Meningioma/physiopathology , Middle AgedABSTRACT
The authors study the different parameters of the stapedius reflex on a 55 patients group with retrocochlear and non tumoral diagnostic is assess by electrophysiologic (BERA, Electrocochleography) and neuroradiologic explorations (TAC), Meato-cisternography, NMR). We realise an comparative study between the results of this group and the results of 2 other groups (98 acoustic neuromas and 104 endocochlear diseases). The test has a moderate sensibility and none specificity in this kind of pathology, because the high percent of false negative (30%), and the positivity on 95% of acoustic neuromas and on 74% of endocochlear diseases.
Subject(s)
Hearing Disorders/diagnosis , Reflex, Acoustic , Vestibulocochlear Nerve Diseases/diagnosis , Acoustic Impedance Tests , Audiometry , Audiometry, Evoked Response , Cochlear Diseases/diagnosis , Diagnosis, Differential , Electrophysiology , Female , Humans , Male , Neuroma, Acoustic/diagnosis , Vertigo/diagnosisABSTRACT
The authors present a case of a cochleovestibular syndrome with a scanner showing a calcified dolico-ektasis of the basilar truncus and the left vertebral artery. The patient had typical Ménière's disease symptomatology. A retrolabyrinthic diagnosis with substantial recruitment was indicated by the results of the audio-vestibular explorations (stapedius reflex, electroculography, early brainstem evoked response, electrocochleography). The electrocochleography with glycerol test indicated labyrinthic hydrops. Finally, some reflections on the role of neurovascular problems in the pathogeny of some cochleovestibular syndromes are put forward.
Subject(s)
Basilar Artery/abnormalities , Cochlear Diseases/etiology , Vertebral Artery/abnormalities , Vestibular Diseases/etiology , Aged , Humans , Male , SyndromeABSTRACT
The authors present 55 cases of non-tumoral retrocochlear impairment, studied over the period between 1984 and 1988 in the ENT University Clinic of Bordeaux. Deafness was the most frequent symptom leading patients to come for consultation (89%). The stapedial reflex was pathological in 70% of the cases. No conclusion could be drawn from electro-occulography. Only the early auditory evoked responses made it possible to reach the diagnosis of retrocochlear impairment in 35% of the cases. Electrocochleography was required in 65% of the cases to establish the topographic diagnosis. The neuro-radiological examination proved to be negative in 48 cases, and positive in 7 cases (6 atrophic symptoms, 1 left vertebral dolichoartery). Among the other etiologies, we noted 14 cases of auditory trauma, 12 vascular pathologies, 9 neurological pathologies, 7 cases of Ménière's disease, and 7 sudden onsets of deafness. The incidence of vasculo-nervous conflict reported by other authors appears very low in this series (with only 1 case).
