Karhart’s notch in ear diseases

Abstract

According to the literature and our research, Karhart’s notch, as a local increase in bone conduction thresholds at frequencies of 500-3000 Hz, is observed not only in otosclerosis, but also in other diseases of the middle ear, especially – with adhesive and secretory otitis. Therefore, it is not appropriate to use the presence of a Karhart’s notch as a pathognomonic sign of otosclerosis. Audiometric diagnostics of non-purulent ear diseases should definitely be supplemented with impedance audiometry.