Hearing Aid Dispenser Written Exam Questions and Answers A+ Graded

Hearing Aid Dispenser Written Exam Questions and Answers A+ Graded db loss of a perforation of TM - CORRECT ANSWER-10-15db loss procedure done to fix perforation - CORRECT ANSWER-tympanoplasty or myringoplasty monomeric spots - CORRECT ANSWER-looks like a hole in TM, but reflects light like a mirror. holes that have healed. aka "mirror membranes" average dimentions of an adult eardrum - CORRECT ANSWER-2.3-2.9cm in length, .7cm in diameters pars tensa - CORRECT ANSWER-lower 4/5 of TM and tight pars flaccida - CORRECT ANSWER-upper 1/5 of TM and flaccid otis externa - CORRECT ANSWER-"swimmers ear" - inflammation of the walls of the EAM. will not cause loss unless swelling blocks canal. treat: warm salt water, drying it, topical antibiotics polyps - CORRECT ANSWER-masses of tissue that grow outward from a surface cholesteatoma - CORRECT ANSWER-non-cancerous tumor in the middle ear. oderous discharge. sometimes perforates upper TM. invasions of skin into the middle ear - sac of concentric rings of protein. causes conductive loss. most dangerous pathology. enlarged canal - CORRECT ANSWER-result of ear surgery. often have no ear drum or ossicular chain. need approval of physician before fitting tympanosclerosis - CORRECT ANSWER-white, chalky calcium deposits caused by degeneration of tissue on eardrum, thicking and scarring from peforations and infections epitympanic cavity - CORRECT ANSWER-attic of middle ear. allows air into mastoid cells of temporal bone. branches several nerves incudotapedial junction - CORRECT ANSWER-top of incus to head of stapes annular ligament - CORRECT ANSWER-footplate of stapes that is held in the oval window speed of sound - CORRECT ANSWER-700mph or 340 m/s (4x as fast through water, 14x as fast through steel) reflection - CORRECT ANSWER-is an echo or a reverberation reverberation - CORRECT ANSWER-often in a small room, 17m or less, reverbs can mask high frequencies echo - CORRECT ANSWER-heard and perceived later than original sound (more than 1/10s after) absorption - CORRECT ANSWER-aborbs sound. can improve environments w/ reflection or reverb. better in warmth and moist diffraction - CORRECT ANSWER-sharpness in the change in direction of sound, bending. high diffraction=bigger wavelengths (low freq) refraction - CORRECT ANSWER-sound passes through one medium to another, change in speed and wavelength infrasound - CORRECT ANSWER-below audible range of 20 Hz ultrasound - CORRECT ANSWER-above audible range of 20K Hz octave - CORRECT ANSWER-anytime the frequency doubles. f(2) = on octave; f(3)= two octaves faintest sound a human can hear - CORRECT ANSWER-10 ^ -16 watts/cm^2 and pressure of .0002 dynes/cm^2 threshold of pain - CORRECT ANSWER-1000 dynes/cm^2 when SPL levels double how many db levels increase? - CORRECT ANSWER-6 db db HL expresses: - CORRECT ANSWER-threshold levels db SPL expresses: - CORRECT ANSWER-voices or environmental sounds pinna function: - CORRECT ANSWER-gather sound, aid in localization, enahnce high freq bw 2k-5k hz aperture - CORRECT ANSWER-entrance to canal, first bend isthmus - CORRECT AN