Pediatric/Objective Testing Flashcards

Question

Acoustic (Stapedial) Reflexes

Answer 1

Bilateral contraction of the stapedius muscles in response to a high-intensity sound •Measured in units of dB HL at 500, 1000, 2000, and 4000 Hz •Normal thresholds around 70–100 dB HL with average threshold level ~85 dB HL •Acoustic reflex arc includes CN VIII, cochlear nucleus, brainstem (at superior olives), and CN VII •Both ipsilateral and contralateral pathways are involved

Answer 2

Acoustic reflex exceedingly sensitive to middle ear disorder •Crossed (contralateral) reflex threshold testing usually carried out at 500, 1000, 2000 Hz •Reflex-eliciting stimuli should not exceed 110 dB HL (unless substantial air–bone gap exists) •If air–bone gap is present, stimulus must be intense enough to overcome the occlusion effect that is present at lower frequencies

Answer 3

Tympanometry for those under six months •Clinically relevant information is obtained at higher frequencies (not at typical 226 Hz measures) because infants have small ear canals •Not uncommon to use probe frequencies around 1000 Hz when assessing infants to account for size differences •Difficult to obtain immittance measures from an infant or child who exhibits excessive body movement or who is crying, yawning, or continually talking •Use of distractive techniques helpful in obtaining measurements in these cases

Answer 4

Auditory evoked potentials (AEPs): measurement of the integrity of electrical voltage evoked in the brain by acoustic stimulation •Auditory EEG obtained •Four major applications of AEPs •Prediction of hearing sensitivity •Neonatal hearing screening •Diagnostic assessment of central auditory nervous system function •Intraoperative monitoring of auditory nervous system function

Answer 5

Non-sedated ABRs < 6 mos Sedated ABR > 6 mos

Answer 6

As the intensity of the auditory stimulus decreases, ABR wave morphology degrades and wave V latency increases •The intensity at which wave V disappears is just below auditory threshold

Answer 7

Frequency-specific, preneural, low-intensity sounds which are generated by the outer hair cells within the cochlea and which emanate into the middle ear and ear canal •Efferent auditory system •Probably not essential to hearing •By-product of active processing by the outer hair cell system

Answer 8

Reveals the integrity of cochlear function •Present OAEs: healthy outer hair cells •Normal hearing sensitivity or at most <30 dB HL hearing loss •Absent OAEs: damaged outer hair cells •Abnormal hearing sensitivity; hearing loss >30 dB HL

Answer 9

Spontaneous: occur without any introduction of an eliciting signal

Answer 10

Evoked: occur during and after presentation of a stimulus Transient (TE): elicited via click stimulus •Stimulates a broader range of outer hair cells on the basilar membrane •Provides timing information •Distortion–product (DP): elicited via pure tones •Provides frequency-specific information about outer hair cell function

Answer 11

Transient (TE): elicited via click stimulus •Stimulates a broader range of outer hair cells on the basilar membrane •Provides timing information

Answer 12

Distortion–product (DP): elicited via pure tones •Provides frequency-specific information about outer hair cell function

Answer 13

Infant Hearing Screening •Objective measure, although degree of hearing sensitivity cannot be ascertained •ABRs can help estimate degree of hearing sensitivity in infants with equivocal results •Can be carried out easily and quickly •Not affected by neuromaturation of central auditory nervous system •Utility limited by outer and middle ear disorders •If there is fluid in the middle ear space, then OAEs cannot be measured

Answer 14

Pediatric assessment •Objective measure; can be obtained even with uncooperative child •Can be obtained quickly and easily •Utility limited by outer and middle ear disorders

Answer 15

Cochlear function monitoring •Used in patients undergoing ototoxic medical treatments

Answer 16

Diagnostic applications •Retrocochlear and/or neurological disorders (e.g., tumors) •Evaluation of patients with functional hearing loss

Answer 17

Montefiore Protocol •All WBN and NICU babies tested within 24-48 hours of birth, prior to discharge •PASS? Done •REFER? Come back for outpatient testing, do tympanometry as well. •FLAT TYMPS? Return in 2 weeks •REFER WITH MOBILE TYMPS? Non-sedated ABR •This appointment will diagnose the hearing loss •Early Intevention, ENT, genetic testing, hearing aids, speech-language therapy, etc.

Answer 18

Moro's reflex: sudden movement of limbs and extension of head in response to sound of 80- 90 dB.

Answer 19

Cochleo-palpebral reflex: Child responds by a blink to aloud sound.

Answer 20

Cessation reflex: Infant stops activity or starts crying in response to sound 90db