Conduction impairment Nerve impairment Compare these two disorders: Otosclerosis
ID: 261061 • Letter: C
Question
Conduction impairment Nerve impairment Compare these two disorders: Otosclerosis and Meniere's disease*. In which category they fall and which is the mechanism of hearing damage that each of them produce.Conduction impairment Nerve impairment Compare these two disorders: Otosclerosis and Meniere's disease*. In which category they fall and which is the mechanism of hearing damage that each of them produce.
Conduction impairment Nerve impairment Compare these two disorders: Otosclerosis and Meniere's disease*. In which category they fall and which is the mechanism of hearing damage that each of them produce.
Explanation / Answer
Menierees Disease : In mennieres , there is excessive production of the endolymph from stria vascularis . This leads to acute rupture of reissners membrane when production increases beyong limit causing vertigo , the 1st symptom. This leads to mixing of endolymph and perilymph causing sodium potassium imbalance. This leads to damage to hair cells leading to hearing loss . But all this while pressure equaluzes which alliw reissners membrane to heal. But this keeps on occuring as a remitting attack .
Now , if their is defect between External auditory canal to foot plate of stapes , its conductive impairment . If defect is in organ of corti / inner ear but the nerve being intact as in menniers , it is sensory . And if the defect is in auditory nerve, it is nerve impairment. In menniers there is sensorineural loss , so out of the two categories given in the question , more apt is Nerve impairment.
Otosclerosis - In the inner ear , there are certain bony parts which remain cartilaginous throughout the life and dont ossify completelt and can hence proliferate on a stimulus. One such area is called as antefenestrum just anterior to which is the oval window. Continuous loud sounds act as a persistent stimulus or may be some other stimulus leads to its proliferation which would lead to fixation of the foot plate of the stapes. Since its a defect from external auditort canal tonfoot plate , its conductive impairment clearly .