Acoustic impedance - Study guides, Class notes & Summaries

Which of the following would best enhance resolution of evoked potential waveforms? - Increase number of averaged stimuli What is the typical MINIMUM common mode rejection ratio of in-phase signals recommended for evoked potential instruments? - 10,000:1 Which of the following cranial nerves is most at risk during acoustic neuroma surgery? - CN VII The impedance of cup electrodes is: - Lower than needle electrodes because of their size Amplitude of an evoked potential depends on which of...

what improves temporal resolution -answer- low line density, high frame rate, narrow sector line, fewer pulse per frame which of the following is true when the dynamic aperature is increased -answer- near zone length increases Which of the following is the standard protocol for digital imaging that allows compatibility and communication between computers, workstations, and network hardware provided by various manufacturers of CT, MRI, and ultrasound -answer- DICOM the beam of an unfocus...

____ is defined as specific area or location where Doppler shift info is being obtained. A. spectral broadening B. nyquist limit C. sample volume D. spectral window -answer- C. sample volume Spatial resolution is: A. the minimum reflector separation required to produce separate echos. B. highest with linear phased arrays. C. the weakest reflected signal the transducer can receive D. another term for slice thickness resolution -answer- A. the minumum reflector separation required to pr...

what is the I SPPA for mechanical bioeffects? correct answer: 190W/cm^2 what is the I SPTA for thermal bioeffects? correct answer: 720mW/cm^2 recommended MI for fetal scanning correct answer: MI < 1.9 recommended TI for fetal scanning correct answer: TI < 0.7 after what fetal age is safe to use PW doppler? correct answer: 14 weeks what does ALARA stand for correct answer: as low as reasonably achievable frequency correct answer: # of cycles/second f = 1/p perio...

reflection return of the ultrasound wave to the transducer from a smooth surface when does the greatest amount of reflection occur when the incident beam is perpendicular to structure (specular reflection) scatter deflection of ultrasound waves from small structures (red blood cells scatter sound) refraction deflection of Ultrasound waves due to media with varied acoustic impedance attenuation loss of Ultrasound signal due to absorption in tissues as it travels ...

What test is to measure middle ear function and asses the integrity of the middle ear muscle reflex immittance audiometry This test assess middle ear function tympanometry The MEMR (middle ear muscle reflex) pathway is assessed with threshold and decay measurements Immittance is an objective test which means what the patient is not required to participate The flow of acoustic energy through the ME system is represented by immittance What is impedance the opposition of energy flow through th...

CAOHC EXAM QUESTIONS WITH CORRECT ANSWERS LATEST UPDATED (100% CORRECT) What is the difference between the requiremtns of OSHA and the recommendations of NIOSH? - answersNIOSH refers to research and recoomendations. OSHA regulates and implements. What are examples of auditory effects on hearing and damage risks? - answers-Tinnitus and hearing loss What are non auditory effects on hearing and damage risks? - answers-Stress, high blood pressure What are potential sources of hazardous noise...

Audiology Praxis Test Questions with 100% Correct Answers For which of the following instruments do national standards or uniform performance standards for calibration exist? a. Pure tone audiometers b. OAEs c. ABR d. all have calibration standards - Correct Answer ️️ -Pure tone audiometers Only pure tone audiometers have established (ANSI) standards for calibration Which is most likely to be introduced deliberately by an examiner during an audiometric exam? a. distorted tone b. s...

The advantages of immersion testing include which of the following? - ️️All of the above. In immersion testing, verification that the search unit is normal to a flat entry surface is indicated by: - ️️Maximum reflection from the entry surface The process of comparing an instrument or device with a standard is called: - ️️Calibration The product of the acoustic velocity of sound in a material and the density of the material is the factor that determines the amount of reflecti...

▪ Newton's law of gravitation - Ansthe fore between two-point masses is directly proportional to the product of the masses and inversely proportional to the square of the separation of the distance between them F=(-GMm)/r^2 ▪ Brownian motion - Ansthe continuous random motion of small particles suspended in a fluid, visible under a microscope ▪ Absolute scale of temperature - AnsA scale for measuring temperature based on absolute zero and the triple point of pure water, with grad...