Original Papers Travaux originaux: Sensorineural Hearing Loss and Somatic Insufficiency

Abstract

Studies of clinical, audiometric and histological defects in patients with conductive otosclerosis, demonstrated the occurrence of subclinical manifestations in the hair, nails, joints and teeth. Light-microscopic examination of the skin in these patients has shown metachromasia of the ground substance and degenerative abnormalities in the collagen and elastic fibres. Structural abnormalities, in the organs developing from the ectoderm and mesoderm, led to the conclusion that otosclerosis is a universal disease characterized by ecto-mesodermal insufficiency, a somatic insufficiency. Optical measurement of the corneal thickness by corneometry has been introduced as an objective method for the diagnosis of somatic insufficiency. This method, now used routinely in our clinic, shows a high frequency of abnormal corneal thickness among patients with otosclerosis. Such a person is termed ‘cornea-positive’. Cochlear otosclerosis with pure sensorineural hearing loss has been studied by X-ray in axial and semiaxial tomography. These patients were often X-ray-positive and among them there were many cornea-positive individuals. Cases with noise-induced hearing impairment may also be cornea-positive, i.e. they may exhibit, somatic insufficiency indicating that their hearing organs are characterized by a decreased resistance to noise.

Corneometry has shown its value in the diagnosis of insufficient somatic constitution typical of individuals at risk.

Depuis 1912 on décrit des syndromes associant troubles auditifs et autres anomalies somatiques. Parmi 125 syndromes différents avec perte auditive de perception, de conduction ou de type mixte, 25 syndromes ont été décrits dans lesquels étaient associés des troubles oculaires. Dans 13 de ces syndromes, il s'agissait d'anomalies de la cornée. La cornéométrie, mesure de l'épaisseur du centre de la cornée, est très importante chez les malades souffrant de pertes d'audition. Les patients présentant une cornéométrie positive, c'est-à-dire une cornée d'epaisseur anormale, se rencontrent souvent parmi les cas d'otospongiose, surtout d'otospongiose cochléaire. Des cornéometries positives se rencontrent aussi chez des patients atteints de surdité de perception ainsi que chez des sujets jouissant d'une audition normale.

Une collaboration plus étroite entre les ophtalmologistes et les services d'ORL et d'audiologie devrait ouvrir de nouvelles perspectives dans l'etude des surdités de perception et dans celle des tissus conjonctifs, reflets de la constitution somatique tant des personnes normales que de celles présentant un risque.

Key Words:

• Otosclerosis
• Cochlear otosclerosis
• Corneometry
• Ecto-mesodermal insufficiency
• Subjects at risk