Abstract: A method and apparatus for diagnosing pathologies of the ear, particularly pathologies such as otitis media, directs into the ear canal a sequence of acoustic waves covering a range of frequencies from a few hundred Hz to several kHz and determines the presence or absence of resonance when the incident and reflected waves are combined. The measurements are made without pressurizing the ear canal and it is not required that the contact between the instrument and the ear be air-tight. Accordingly, essentially no discomforture of the patient results from use of the instrument. The requisite measurements are made quickly (of the order of tens of milliseconds) and thus the distorting effects of patient movement are effectively eliminated. An improved version of the instrument is completely self-contained and hand-held and has the form of a "tee" in which the resonant frequency and amplitude are visually indicated by means of horizontally-and-vertically disposed arrays of light-emitting diodes.

Abstract: The present invention provides a method and apparatus for diagnosis of various ear pathologies, including the diagnosis of effusions of the middle ear associated with Otitis Media. The method is practiced by determining a quantity related to the complex acoustic impedance of the ear, namely the Vector Sum of an incident signal, propagating down the ear canal, and the same signal reflected from the tympanic membrane and middle ear components. The results obtained are compared with the expected results of a healthy ear.