FINAL - Central/Neural Disorders Flashcards
Acoustic Neuroma
Define
Unilateral or Bilateral?
Also called Vestibular Schwannoma
Benign tumor
Unilateral
*Schwann Cells- surround the Vestibular branch of 8th cranial nerve
Bilateral Schwannomas
NF2 Neurofibromatosis
account for 5% of acoustic tumors
Initial complaints of Acoustic Neuromas
Progressive HL
Tinnitus
Dizziness
Facial weakness*
Acoustic Neuroma Audiometry
Unilateral
Conductive or SNHL
Speech Discrimination
Acoustic Reflexes
Unilateral asymmetric
SNHL (high frequency)
Degree of loss not correlated to tumor size
Poorer speech discrimination + PB Rollover
Abnormal reflexes
ABR Abnormalities
If Wave V present- delayed wave V latency on tumor size
Interaural Wave V latency difference
Acoustic Neuroma Treatment
Surgical- Ability to preserve hearing/blood supply to cochlea & 8th nerve depends on size of tumor
Auditory Neuropathy
Define
Characteristics
Cause?
Age?
Condition in which normal cochlea OHC function but abnormal neural function starting with 8th nerve
- Idiopathic, Genetic
- Age- Infancy/Childhood
Auditory Neuropathy Treatment
Need to improve signal to noise ratio
amplification
FM system
Cochlear Implant
Auditory Neuropathy Audiometry
Thresholds?
OAEs, Acoustic Refleces- Absent or Present
WR?
- Variable thresholds (normal-profound)
- Auditory brainstem response is absent/normal
- Cochlear Micophonic: present
- OAEs present
- WR poor
- Acoustic Reflexes absent
Nonorganic (Functional) HL
define
Apparent loss without sufficient pathological evidence to explain
Define Malingering
Deliberate falsifcation of physical or psychological symptoms for special gain
Define Pseudohypacusis
False hearing loss
Stenger Test
Used for bilateral/asymmetric ( > 20 dB)
two tones of same frequency are introduced simultaneously to both ears. Only louder one will be perceived.
Positive Stenger
Failed to respond
indicates they actually hear it in their poor ear
Negative Stenger
Respond
suggests absense of nonorganic loss