Advanced Diagnostics & Troubleshooting Flashcards
7 cards from real ABA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Advanced Diagnostics & Troubleshooting flashcards as text
Contralateral suppression of OAEs is used to assess the function of which auditory structure?
Answer: Medial olivocochlear (MOC) efferent system
The medial olivocochlear bundle suppresses OAE amplitude when noise is presented contralaterally; measuring this suppression tests the integrity of the efferent auditory system.
A patient shows normal hearing thresholds but absent ipsilateral and contralateral MEMRs with a normal tympanogram. Which condition should be considered first?
Answer: Bell's palsy (CN VII lesion)
CN VII (facial nerve) is the efferent limb of the MEMR; facial nerve lesions eliminate the reflex bilaterally regardless of hearing status or middle ear function.
High-resolution CT of the temporal bones is the preferred imaging modality for detecting:
Answer: Superior semicircular canal dehiscence
CT with fine cuts (0.5 mm or less) in the Poschl plane directly visualizes the bony defect over the superior canal in SSCD.
During an ABR, electrode impedance suddenly increases mid-test. The most immediate consequence is:
Answer: Increased noise floor reducing response reliability
High electrode impedance increases the noise floor, degrading signal-to-noise ratio and making waveform identification less reliable.
A patient's audiogram shows a bilateral 'cookie-bite' (mid-frequency) sensorineural hearing loss. The most common etiology for this pattern is:
Answer: Hereditary (genetic) hearing loss
A mid-frequency 'cookie-bite' configuration is strongly associated with genetic hearing loss, particularly autosomal dominant mutations affecting mid-cochlear structures.
In the acoustic reflex decay test, what constitutes a positive (abnormal) result?
Answer: Amplitude decays to 50% or less within 5 seconds at 500 or 1000 Hz
Abnormal reflex decay is defined as the MEMR amplitude dropping to ≤50% of its initial value within 5 seconds, indicating possible retrocochlear (CN VIII) pathology.
When performing speech audiometry for a patient suspected of auditory processing disorder, the most diagnostically useful test battery includes:
Answer: Dichotic digit test, low-pass filtered speech, and compressed speech tests
APD batteries include dichotic tests (e.g., dichotic digits), temporal processing tests, and degraded speech measures to stress the central auditory system beyond peripheral sensitivity.