General Topics Flashcards
What are the consequences of air embolism
>50 cc of air causes intensive pulmonary artery vasoconstriction, pulmonary edema, and cor pulmonale. >200 cc of air is fatal.
What is the incidence of permanent hypoparathyroidism after total thyroidectomy
1 - 5%.
What is the incidence of permanent recurrent laryngeal nerve injury after total thyroidectomy
1 -4%.
What is the fistula rate following free jejunal transfer (non-irradiated patients)
10- 20%.
What % of laryngectomy patients who fail voice restoration following tracheoesophageal puncture (TEP) suffer from cricopharyngeal spasm
12%.
What is the incidence of SNHL after radiation therapy for nasopharyngeal cancer
14%.
What is the fistula rate in patients who have had prior irradiation requiring total laryngectomy and partial pharyngectomy
15 - 20%.
What is the incidence of tracheoinnominate fistula after tracheostomy
2%.
What is the most effective duration for perioperative antibiotic administration
24 hours.
What % of patients with tracheoinnominate fistulae survive
25%.
What is the incidence of significant SNHL after revision stapedotomy
3 - 30°/o (up to 14% profound).
What is the most common complication from microsurgical reconstruction
36% suffer medical complications (pulmonary problems, prolonged ventilatory support, acute ethanol withdrawal).
What is the recurrence rate following excision of a TGDC without removal of the midportion of the hyoid and the ductal remnant
38%.
What is the perioperative mortality rate of gastric pull-up
5- 20%.
What is the rate of major complications after gastric pull-up
50%.
What % of all instances of tracheal bleeding developing 48 hours or longer after surgery are caused by tracheoinnominate fistulae
50%.
What is incidence of persistent diplopia after orbital reconstruction
7%.
What is the incidence of complications after PEG
9-15%.
What are the most common complications of lateral tympanoplasty
Anterior blunting, lateralization, epithelial pearls, canal stenosis.
What is the management of injury to the sigmoid sinus during mastoidectomy
Apply gentle pressure, place a Surgicel or Gelfoam patch, and continue with surgery.
Where do strictures most often occur after free jejunal transfer
At the inferior anastomosis between the jejunum and esophagus.
Where do fistulas most often occur after free jejunal transfer
At the superior anastomosis between the jejunum and pharynx.
What are the signs of air embolism
Audible sucking sound in the wound, machine-like cardiac murmur, dysrhythmias, sudden systemic hypotension, decreased end expiratory C02, increased CVP.
What are the most common complications of pharyngeal flap surgery
Bleeding, airway obstruction, obstructive sleep apnea.
Which patients are at a higher risk of pneumothorax after tracheostomy
Children.
What is the best test to differentiate between cricopharyngeal spasm and stricture in patients who fail voice restoration following TEP
Contrast videotluoroscopy.
Which complication is most likely to be avoided with endoscopic diverticulectomy versus open diverticulectomy
Damage to the recurrent laryngeal nerve.
What is the treatment of pneumocephalus
Emergent drainage with needle aspiration, airway diversion (i.e. tracheostomy), nasal repacking.
What is the most common complication after orbital reconstruction
Enophthalmos.
What are the symptoms and signs of a poststapedectomy perilymph fistula
Episodic vertigo, especially with exertion, sensorineural hearing loss, loss of speech discrimination, and nystagmus with changes of air pressure on the TM.
What is meant by “carotid blowout precautions”
Establish IV access with 2 large bore IVs, type and cross 2 units PRBCs, have an intubation tray at the bedside, and educate nursing staff.
What is the most serious complication of lateral pharyngotomy
Excessive retraction on the great vessels leading to thrombosis or embolism.
What structure is most at risk during removal of a 1st branchial arch sinus
Facial nerve.
What are the 2”d most commonly isolated bacteria
Gram-negative aerobic bacteria.
What is the most common complication of parotidectomy
Hematoma.
What electrolyte problem is disproportionately associated with gastric pull-up
Hypocalcemia secondary to impaired calcium absorption and inadvertent parathyroid resection during thyroidectomy.
What is the incidence of CV A and mortality from carotid blowout
I 0% CV A and I % mortality if volume is repleted prior to going to the OR. 50% CV A and 25°/o mortality if volume is not repleted prior to going to the OR.
What factor best predicts the risk of a major complication following head and neck oncologic surgery
I O% loss of baseline body weight.
What is the incidence of clinically significant VPI after adenoidectomy
I: 1500 - 3000.
What is the treatment for post-adenoidectomy VPI
If it persists beyond 2 months, speech therapy; beyond 6 - 12 months, palatal pushback, pharyngeal flap surgery, or sphincter pharyngoplasty.
What is the management of intraoperative violation of the labyrinth
Immediate application of a Gel foam patch or other tissue seal (other than fat).
What is the rate of wound infection following contaminated head and neck surgery with use of perioperative antibiotics consisting of ampicillin/sulbactam or clindamycin
IS%.
During stapedectomy, the entire stapes footplate falls into the vestibule. What should be done
It should be left in the vestibule, as attempts to retrieve it are more likely to cause damage than leaving the footplate where it is.
A patient develops a CSF leak after resection of an acoustic neuroma. A pressure dressing and lumbar drain are placed with no improvement. Wound exploration and reclosure are performed, and the leak recurs. What is the next step
It the tympanic membrane is intact and hearing is present, plug the eustachian tube via a middle fossa approach. If the tympanic membrane is not intact and hearing is not present, perform a blind sac closure of the external auditory canal and obliterate the middle ear and eustachian tube.
What is the most common location for iatrogenic labyrinthine fistula formation during mastoidectomy
Lateral semicircular canal.
What is the initial treatment for a chyle leak diagnosed 3 days after neck dissection
Maintain drains and begin medium-chain triglyceride tube feedings.
Where is the facial nerve most commonly injured during mastoid surgery
Near the 2”d genu as it enters the mastoid cavity.
4 weeks after ORlF of a mandibular body fracture, your patients presents with an exposed plate and purulent drainage. The reduction is grossly intact. What do you do
Open wound, remove involved tooth if applicable, remove hardware, and assess union; if nonunion is present, most patients will heal with MMF; other option is plate and bone graft (external approach).
10 days after ORIF of a mandibular body fracture, your patient presents with an exposed plate and purulent drainage. The reduction is grossly intact. What do you do
Open wound, remove involved tooth if applicable; if hardware is loose, replace it with a new plate; if hardware is rigid, continue drainage, wound care.
What are the complications from radiation overdosage in the treatment of NPC
Osteoradionecrosis, brain necrosis, transverse myelitis, hearing loss, hypopituitarism, hypothyroidism, optic neuritis.
What can cause postoperative pneumocephalus
Overly aggressive drainage of CSF via a lumbar drain or ball-valve action of the flaps used to reconstruct the skull base.
What is the treatment for air embolism
Pack wound, compress jugular veins, aspirate air if right atrial catheter is in place, insert needle into right ventricle from under the xiphoid, switch to 1 00°/o 0 2 and stop nitrous, place patient in left lateral Trendelenburg position.
Which patients are at greater risk for a “perilymph gusher”
Patients with congenital stapes fixation and a patent cochlear aqueduct or a large vestibular aqueduct.
What is the most common postoperative complication of pressure equalizing tube insertion
Persistent otorrhea.
What are the risk factors for innominate artery rupture after tracheostomy
Placement of trach below the 3rd ring; aberrant course of the innominate artery; use of a long, curved tube; overhyperextension of the neck during the procedure; prolonged pressure by inflated cuff; and tracheal infection.
What is the most common complication of segmental mandibulectomy defect reconstruction with plates
Plate exposure.
What is the most common cause of mortality in pediatric patients who undergo tracheostomy
Plugging or accidental decannulation in children
Unbeknownst to the surgeon, the dura is torn during mastoidectomy, and postoperatively, the patient develops a severe headache, followed by hemiplegia and coma. What has likely happened
Pneumocephalus; torn dura can create a ball valve-like effect and trap air from the middle ear. Influx of air may occur during Valsalva or as a result of high intracranial negative pressure due to the rapid escape of CSF through the tear.
What is the most common cause of infection after ORIF
Poor plating technique.
What is the most common complication of stapedotomy
Prosthesis displacement.
What is a “perilymph gusher”
Rapid release of perilymph after stapes footplate fenestration due to pressure and fluid from the CSF compartment venting through the inner ear.
What is the only preoperative factor to significantly increase the risk of postoperative pulmonary complications
Recent smoking history.
What is the management of a “perilymph gusher”
Reduction of CSF pressure with mannitol and/or a lumbar drain, application of a tissue seal over the oval window fistula using fascia, perichondrium, or fat and secured with a stapes prosthesis, and postoperative hospitalization with continued reduction in CSF pressure.
What are the most common complications of gastric pull-up
Regurgitation, cervical dysphagia, stricture, anastomotic leak.
What is the treatment for infected extraoral mandibular ORIF
Removal of the tooth and the failed plate, debridement of dead bone, placement of a large reconstruction plate, and primary grafting if inadequate bone contact exists.
What is the management of injury to the dura with CSF leak during mastoidectomy
Repair with temporalis fascia held in place with sutures or packing and continue with surgery; small tears can be managed with a Surgicel or Gelfoam patch.
What are the most common complications of acoustic neuroma resection
SNHL, paralysis of VII, CSF leak (10-35%), meningitis (1-10%), intracranial hemorrhage (0.5-2%).
What are the most commonly isolated bacteria from wound infections following major contaminated head and neck surgery
Staph aureus and beta-hemolytic streptococci.
What is the most common organism identified in patients with pneumonia after major surgical resection of the upper aerodigestive tract
Staphylococcus aureus.
Ten days after stapedectomy, your patient complains of progressive hearing loss and vertigo that does not respond to steroids. What do you do
Take the patient back to the OR to explore for a granuloma. If one is found, remove the granuloma and place a new prosthesis with a tissue seal over the oval window.
What are 2 important techniques to prevent postoperative fistula formation
Tension-free closure and perioperative antibiotics.
If the leak does not resolve, what is the next step in management
TPN.
What surgical procedure is the most common cause of iatrogenic vocal cord paralysis in children
Tracheo-esophageal fistula repair.
Two weeks after undergoing salvage surgery on the neck, a patient loses 800 cc of blood from the operative site. If a bleeding source is not found on carotid arteriogram, what is the next step in management
Venous angiography with endovascular occlusion.
What is the youngest age approved by the FDA for cochlear implantation?
12 months.
What percent of laryngectomy patients who fail voice restoration following TEP suffer from cricopharyngeal spasm?
12%.
What percent of patients with glottic insufficiency will attain complete closure after voice therapy?
20%.
What is the critical period for stimulating the auditory system?
3 years of age.
A patient with Meniere’s disease is able to work, drive, and travel but must exert a great deal of effort to do so and is “barely making it.” What functional level is heJshe?
4 (out of 6).
What percent of patients with severe tinnitus are successfully treated with masking devices?
56-64%.
What factor is most predictive of enhanced ability to understand speech with a cochlear implant?
Age at onset of deafness.
What are the basic steps of sound processing performed by cochlear implants?
Amplification, compression, filtering, and encoding.
What are the three general types of hearing aids?
Analogue devices, digitally programmable systems, and digital signal processors.
After 3 months of voice therapy, what percent of benign vocal cord lesions will reduce in size or resolve?
Approximately 45% will reduce in size and 10% will completely resolve.
What type of masking device is recommended for patients with hearing loss?
Behind-the-ear hearing aid.
What is the habituation technique for the treatment of tinnitus?
Binaural broad-band noise generators are worn for at least 6 hours everyday for at least 12 months.
What are the three categories of compression?
Compression limiting, wide dynamic range compression, and automatic volume control.
What is the gain of a hearing aid?
Difference in the output of the instrument relative to its input.
What are the three options for speech production after total laryngectomy?
Esophageal speech, tracheoesophageal puncture (TEP), and electrolarynx.
What are the different types of assisted listening devices?
FM systems, soundfield systems, infrared systems.
What utensil can be used to help move food to the back of the tongue in patients who have had a glossectomy?
Glossectomy feeding spoon.
What are the components of a cochlear implant?
Implantable stimulator, headpiece and transmitter, and speech processor.
What are the criteria for pediatric cochlear implantation?
In both prelingual and postlingual children, bilateral severe to profound SNHL (only profound hearing loss in children < 20-30% in children capable of testing; lack of auditory development with a proper binaural hearing aid trial documented by testing or parental questionnaire (for very young children); no medical contraindication with intact cochlea and auditory nerve.
What exercises have been shown to help improve swallowing function?
Isotonic/isometric neck exercises where the patient lies on his/her back and lifts the head and isometric resistance tongue exercises.
How can one determine if maskers will be effective in the treatment of tinnitus?
Measure the minimum masking level (MML) and loudness matching; if the MML is lower or equal to the loudness matching, maskers will likely be effective.
What is a linear amplification system?
One in which the amplitude output is directly proportional to the signal input until saturation is reached.
After cochlear implantation, children have better outcomes in which type of learning environment: total communication or oral education?
Oral education.
What device can be used to decrease nasal regurgitation in patients who have a defect in their palate?
Palatal obturator.
What is the supraglottic swallow?
Patient inhales, takes food into mouth, performs Valsalva to close the glottis, coughs to clear debris from the glottis, swallows, and then exhales.
Which patients are least likely to benefit from vestibular rehabilitation programs?
Patients with fluctuating nonstable vestibular lesions such as Meniere’s disease; patients in whom no provocative maneuvers or postural control abnormalities are found on examination.
How do linear amplification systems limit output?
Peak clipping.
What are the criteria for cochlear implantation in prelingual deaf adults?
Profound bilateral SNHL; minimal benefit from properly fitted hearing aids; psychological and motivational suitability; no medical contraindications to surgery with intact cochlea and auditory nerve.
Why are patients prone to aspiration after supraglottic laryngectomy?
Secondary to loss of epiglottis and closure of false cords, to decrease in laryngeal elevation and loss of afferent stimulation to the vocal cords with tracheostomy, and to decrease in sensation from loss of superior laryngeal nerves during tumor resection.
What are the criteria for cochlear implantation in postlingual deaf adults?
Severe to profound bilateral sensorineural hearing loss (SNHL); properly aided sentence recognition score (HINT)
What is the frequency response of a hearing aid?
The gain of the hearing aid across a range of frequencies.
What is a nonlinear amplification system?
The ratio of input to output is
Why are in-the-ear hearing aids not recommended in patients with tinnitus?
They can produce too much occlusion effect and amplification of the lower frequencies, resulting in exacerbation of tinnitus.
Which patients benefit most from nonlinear amplification systems?
Those with a small range between their threshold for hearing and their loudness discomfort level (LDL).
How do prelingually deafened children with cochlear implants compare with those with multichannel tactile aids in open-set word recognition skills?
Those with cochlear implants do better.
What is the purpose of the “chin-tuck” when swallowing?
To decrease the speed of the bolus passage.
What is the basic function of assisted listening devices?
To improve the signal-to-noise ratio at ear level by 15-20 dB in moderate noise and reverberation.
In which direction should a hemiparetic patient turn their neck to assist with swallowing?
Toward the hemiparetic side.
True/False: Cochlear implantation has been shown to relieve tinnitus in a large percentage of profoundly deaf individuals.
True.
True/False: Speech perception of prelingually deafened children who have had cochlear implants for 5 years is likely to be equal to or better than postlingually deafened patients.
True.
What devices are used in the habituation technique for the treatment of tinnitus?
Viennatone maskers.
Which of these is most appropriate for patients with substantially reduced dynamic ranges?
Wide dynamic range compression.
A 3-year-old child with cerebral palsy and bilateral severe SNHL meets the above criteria. Is he/she eligible for cochlear implantation?
Yes.
What is the best imaging study to differentiate between cricopharyngeal spasm and stricture in patients who fail voice restoration following TEP?
Contrast videofluoroscopy.
NAME THE SYNDROME Large calvaria with frontal bossing, low nasal bridge, midface hypoplasia, congenital hearing loss:
Achondroplasia.
NAME THE SYNDROME Craniosynostosis, beak nose, stapedial fixation, hypoplastic midface with relative mandibular prognathism, syndactyly, cervical fusion, foramen magnum stenosis:
Apert’s syndrome (acrocephalosyndactyly).
NAME THE SYNDROME Facial port-wine stain, macroglossia, hypertrophy of pancreatic islet cells with hyperinsulinemia and hypoglycemia, and hypertrophy of the renal medulla and liver:
Beckwith-Wiedemann syndrome.
NAME THE SYNDROME Multiple blue, compressible, cutaneous angiomas and visceral angiomas
Blue rubber bleb nevus syndrome.
What are the differences between Apert’s syndrome and Crouzon’s syndrome?
Children with Apert’s syndrome also have syndactyly of the hands, a significant incidence of cleft palate and more serious facial deformities.
What are the differences between Apert’s syndrome and Crouzon’s syndrome
Children with Apert’s syndrome also have syndactyly of the hands, a significant incidence of cleft palate and more serious facial deformities.
NAME THE SYNDROME Ipsilateral tongue paralysis and fasciculations along with manifestations of Vernet’s syndrome secondary to a lesion in the jugular foramen extending below the skull base:
Collet’s syndrome.
NAME THE SYNDROME Craniosynostosis, maxillary hypoplasia, shallow orbits, proptosis, cervical fusion:
Crouzon’s syndrome (craniofacial dysostosis).
NAME THE SYNDROME Epicanthal folds, macroglossia, short neck, occipitoatlantoaxial instability:
Down syndrome.
NAME THE SYNDROME Hyperextensible skin, joint hypermobility, easy bruising, cervical ligament instability:
Ehlers-Danlos syndrome.
NAME THE SYNDROME Microcephaly, short palpebral fissures, epicanthal folds, long and smooth philtrum, thin upper lip vermilion border, congenital hearing loss, midface hypoplasia, C2-C3 fusion:
Fetal alcohol syndrome.
What syndromes are associated with well-differentiated thyroid carcinoma in children?
Gardner’s syndrome and Cowden syndrome.
What syndromes are associated with well-differentiated thyroid carcinoma in children
Gardner’s syndrome and Cowden syndrome.
NAME THE SYNDROME Hemifacial microsomia, epibulbar dermoids, colobomas, micrognathia, cleft lip/palate, microtia, facial nerve anomalies:
Goldenhar’s syndrome (oculo-auriculo-vertebral spectrum).
NAME THE SYNDROME Nevoid basal cell carcinomas, odontogenic keratocysts, palmar pits, bifid ribs:
Gorlin.
NAME THE SYNDROME Uveitis, parotid enlargement, Vllth nerve paralysis:
Heerfordt’s syndrome.
What are the characteristics of Crouzon’s syndrome
Hypoplasia of the orbits, zygomas and maxilla and variable craniosynostoses.
What are the characteristics of Crouzon’s syndrome?
Hypoplasia of the orbits, zygomas and maxilla, and variable craniosynostoses.
NAME THE SYNDROME Short, webbed neck, congenital hearing loss, cervical and/or thoracic fusion:
Klippel-Feil syndrome.
Port-wine stain, AV fistula, extremity angiomatosis, and skeletal hypertrophy:
Klippel-Trenaunay-Weber syndrome.
NAME THE SYNDROME Midface retrusion, depressed and broad nasal bridge, congenital joint dislocations, congenital hearing loss, cervical instability:
Larsen’s syndrome.
Multiple cavernous hemangiomas, dyschondroplasia, and propensity for development of chondrosarcoma:
Maffucci syndrome.
What other syndromes is blue rubber bleb nevus syndrome associated with?
Maffucci’s and Klippel-Trenaunay-Weber syndromes.
NAME THE SYNDROME Coarse facial features, prominent frontal bones, mandibular prognathism, vertebral anomalies:
Mucopolysaccharidoses.
What is a sequence
Multiple defects arising from a single structural anomaly (ie Pierre Robin).
What is an association
Nonrandom occurrence of a group of anomalies not known to be a sequence or a syndrome (ie CHARGE, VATER)
Multiple telangiectasias of the skin and mucous membranes:
Osler-Weber-Rendu syndrome (hereditary hemorrhagic telangiectasia).
NAME THE SYNDROME Congenital hearing loss, blue sclerae, scoliosis:
Osteogenesis imperfecta.
What is a syndrome
Pattern of multiple anomalies pathogenetically related.
NAME THE SYNDROME Cleft palate, micrognathia, glossoptosis:
Pierre Robin sequence.
What is the most frequently involved cranial suture in Crouzon’s syndrome?
The coronal suture.
What is the most frequently involved cranial suture in Crouzon ‘s syndrome
The coronal suture.
Treacher Collins syndrome (mandibulofacial dysostosis) is characterized by hypoplasia of what embryologic structures?
Those derived from the first and second brachial arches.
Treacher Collins syndrome (mandibulofacial dysostosis) is characterized by hypoplasia of what embryologic structures
Those derived from the first and second brachial arches.
NAME THE SYNDROME Pterygium colli, epicanthal folds, cervical cystic hygromas, cervical hypoplasia:
Turner’s syndrome.
NAME THE SYNDROME Tracheoesophageal fistula with esophageal atresia, cervical segmentation defects, imperforate anus:
VATER syndrome.
NAME THE SYNDROME Cardiac malformations, hypernasal speech, clefting of the secondary palate, slender hands, learning disabilities:
Velocardiofacial syndrome.
NAME THE SYNDROME Paralysis of IX, X, and XI from a lesion in the jugular foramen:
Vernet’s syndrome.
NAME THE SYNDROME Sympathetic trunk compromise in addition to IX-XII paralysis secondary to a lesion extending out of the jugular foramen:
Villaret’s syndrome.
Hemangiomas of the cerebellum and retina and cysts of the pancreas and kidney:
Von Rippel-Lindau disease.
NAME THE SYNDROME White forelock, hearing loss, iridial chromic heterogeneity, dystopia of medial canthi:
Waardenburg’s syndrome.
NAME THE SYNDROME Klippel-Feil anomaly with SNHL, VI nerve palsy, retracted globe, fused ribs:
Wildervanck syndrome (cervico-oculo-acoustic).
What is the critical period for stimulating the auditory system
- 3 years of age.
What are normal ear canal volumes in children and adults
0.5 - 1.0 cc in children, 0.6 - 2.0 cc in adults.
What is the normal interaural attenuation value for bone conduction
0db
SRT should be within __ dB of pure tone average (PTA).
10 dB.
When determining interpeak latencies, which waves are compared
1-111, 1-V.
What noise level begins to cause pain
140 dB.
A patient has a negative Rinne at 256 Hz AS. At 512 Hz and 1024 Hz it is positive as it is at all three frequencies AD. The Weber test lateralizes to the left at all three frequencies. He hears a soft whisper AD and a soft to medium whisper AS. What is his hearing loss
15 dB conductive H L AS.
What range of frequencies can the human ear detect
20 - 20,000 Hz (greatest sensitivity is from 500 to 3000 Hz).
What is the incidence of ossification after pneumococcal meningitis
20-30%.
Which frequencies are air conduction thresholds obtained from
250 - 8000 Hz at octave intervals.
What % of normal ears emit spontaneous OAEs
35- 60%.
What is normal interaural attenuation of air conducted tones
40 - 80 dB depending on whether ear inserts or headphones are used and also on the frequency being tested.
What % of the time will the Rinne test miss an air-bone gap
50%.
What % of patients will have new bone growth covering the round window niche and membrane during cochlear implantation
50%.
In the normal ear, contraction of middle ear muscles occurs at which pure tones
65 - 95dB HL.
What is a normal word recognition score
90- 100°/o.
What % of normal ears demonstrate evoked OAEs
96 - IOO%.
What is rollover
A decrease in speech discrimination scores when presented at higher intensities; suggestive of a retrocochlear lesion.
When comparing the summating to the compound action potential, what value is considered abnormal
A ratio greater than or equal to 0.45.
How is this measured
A signal is presented I 0 dB above the acoustic reflex threshold for I 0 seconds; if the response decreases to one half or less of the original amplitude within 5 seconds, the response is considered abnormal and suggestive of retrocochlear pathology.
What stimulus is used to evoke the auditory brainstem response
A simple acoustic click, between 2000-4000 Hz.
What is a spondee
A two-syllable word spoken with equal stress on both syllables.
What factor is most predictive of enhanced ability to understand speech with a cochlear implant
Age at onset of deafness.
What are the basic steps of sound processing performed by cochlear implants
Amplification, compression, filtering, and encoding.
What is the glycerol test
An audiogram is given just prior to and 3 hours after ingesting 6 oz of 050. An improvement of 15 dB for at least one frequency, 12% SDS, or I 0 dB SRT is significant for Meniere’s disease (the glycerol acts as a diuretic).
What are the 3 general types of hearing aids
Analogue devices, digitally programmable systems, and digital signal processors.
Where is the earliest lesion of otosclerosis most commonly found
Anterior edge of the oval window (fissula ante fenestrum).
What technique can be used to differentiate the summating potential (SP) from the nerve potential of VIII (AP)
AP is a neural response that will respond to higher rates of stimulation. SP is a preneural response that is not affected by higher rates of stimulation. Therefore, increasing the click rate of the stimulus will affect the AP but not the SP.
Where are the recording electrodes placed
As close as possible to the cochlea and auditory nerve (promontory, tympanic membrane, external auditory canal).
What test can be use to exclude the absence of aidable hearing when the ABR is absent at maximum levels
ASSEP (Auditory steady-state evoked potentials).
What is the significance of a negative Rinne at 256 Hz? 512 Hz? 1024 Hz
At least a 15 dB conductive hearing loss (CHL), 25-30 dB CHL, and 35 dB CHL, respectively.
What 3 audiometric test techniques are used to obtain behavioral response levels from a child
Behavioral observation audiometry (BOA), visual reinforcement audiometry (VRA), and conditioned play audiometry (CPA).
Where is the peak pressure point in a normal tympanogram in an adult
Between -1 00 and +40 daPa.
When does masking dilemma occur
Bilateral 50 dB or greater air-bone gaps.
What are the criteria for pediatric cochlear implantation
Bilateral SNHL of 90 dB HL or poorer in the better ear across the speech frequencies and no better than chance performance on open-set word and sentence materials (30%); no appreciable benefit from hearing aids, and no medical contraindication to surgery.
How are air and bone conduction thresholds measured
By first obtaining a positive response, then lowering the intensity by I 0 dB increments until no response is obtained.
How is SRT measured
By starting at minimal intensity and ascending in I 0 dB increments until the correct response is identified.
What is measured in electrocochleography
Cochlear microphonic action potential, action potential of VIII, the summating and compound action potentials.
What are the 3 categories of compression
Compression limiting, wide dynamic range compression, and automatic volume control.
What is adaptation
Continuous stimulation leads to decrease in the intensity of stapedial contraction.
What are the typical objective auditory findings in patients with auditory neuropathy
Decreased or absent ABR, normal OAEs, absent auditory reflexes, very poor speech discrimination, mild to profound pure tone hearing loss.
What is the gain of a hearing aid
Difference in the output of the instrument relative to its input.
Where is bone-conducted sound transmitted
Directly to the cochlea.
Which of these is evoked by 2 pure tones
DPOAE.
When is monopolar electrocautery contraindicated in cochlear implant patients
During revision and other head and neck surgery in a patient with a cochlear implant and during primary cochlear implantation in a patient with another electronic medical device.
T/F: The absence of the click-evoked ABR at maxiumum levels (100 dB) excludes the presence of aidable hearing
False.
What are the most common complications of cochlear implantation
Flap complications, electrode dislocation or malinsertion, facial nerve injury, stimulation of facial nerve postoperatively.
What are the different types of assisted listening devices
FM systems, soundfield systems, infrared systems.
What is the speech detection threshold (SDT)
Hearing level at which 50°/o of the spondaic words are detected; usually 6 - 7 dB lower than the SRT.
What condition increases the likelihood of this happening
History of meningitis.
What does each wave represent
I - eighth nerve II - cochlear nucleus I I I - superior olivary complex IV - lateral lemniscus V- inferior colliculus {note: e.colij
How many times louder is 60 dB than 0 dB
I ,000,000 times.
What are the components of a cochlear implant
Implantable stimulator, headpiece and transmitter, and speech processor.
What effect does pre-test familiarization with spondee words have on SRT
Improves speech reception threshold by 4-5 dB.
What is the difference in these interpeak latencies
Increased 1-111 intervals are almost always indicative of retrocochlear pathology, whereas increased 1-V intervals is more likely associated with noise-induced SNHL.
Into which ear is the implant placed if there is no difference acoustically between ears
Into the better surgical ear as determined by CT scan (side with the least amount of ossification or fibrosis within the scala tympani).
Into which ear is the implant placed if the patient has had different durations of hearing impairment in each ear
Into the ear that has had the shortest duration of deafness.
What factors influence outcome after cochlear implantation
Length of auditory deprivation, pre-versus post-lingual onset of deafness, etiology of deafness, electrode insertion length, patient motivation, family support, age at the time of implantation.
What is the speech awareness threshold (SAT)
Lowest level at which the patient can detect the presence of speech.
What does an abnormal ratio suggest
Meniere’s disease.
What is conditioned play audiometry (CPA)
Method of assessing hearing levels in children aged 2-5 years where the child is trained to respond to auditory stimuli with a motor response (e.g., pointing to pictures)
What is visual reinforcement audiometry (VRA)
Method of assessing hearing levels in children aged 6-24 months by employing lighted transparent toys to reinforced responses (head turn) to auditory stimuli.
What is behavioral observation audiometry (BOA)
Method of assessing hearing levels in children less than 2 by observing reflexive/behavioral responses to sound stimuli at different frequencies.
What 2 inner ear malformations are contraindications to cochlear implantation
Michel deformity and small internal auditory canal syndrome (
Why are OAEs useful as a screening tool in infants
Nearly 100% of people demonstrate evoked OAEs; testing is non-invasive and inexpensive; test time is short; cochlear hearing loss exceeding 30 dB can be detected.
If otoacoustic emissions are present, can retrocochlear pathology be ruled-out
No.
What is a linear amplification system
One in which the amplitude output is directly proportional to the signal input until saturation is reached.
A patient who recently had a cochlear implant placed complains of throat pain every time someone talks to him. What has happened
One of the electrodes of the cochlear implant is stimulating Jacobson’s nerve on the promontory.
What psychological problems are contraindications to cochlear implantation
Organic brain dysfunction, mental retardation, psychosis, unrealistic expectations.
What is the most common cause of an air-bone gap >50d8
Ossicular discontinuity.
What is the most common cause of conductive hearing loss in people 15-50 years of age
Otosclerosis.
Which cells emit otoacoustic emissions (OAEs)
Outer hair cells.
What is the significance of speech discrimination scores
Patients with cochlear and retrocochlear pathology will have poor to very poor scores, respectively; those with only conductive hearing loss will have normal scores when the intensity level is sufficiently loud.
How do linear amplification systems limit output
Peak clipping.
How is speech discrimination testing performed
Phonetically balanced monosyllabic word lists (50) are administered at 30-50 dB above threshold and the % correct is identified.
What are the criteria for cochlear implantation in adults
Postlingual, profound bilateral SNHL in excess of 95 dB PTA, no benefit from hearing aids (word discrimination
How will a retrocochlear lesion affect the ABR
Prolongation of absolute wave V latency, 1-V latency, and interaural wave V latency.
How can this be treated
Removal of the electrode(s) stimulating the nerve (probably 17 or 18).
What does the finding of elevated acoustic reflex in the presence of normal hearing or mild SNHL and a normal tympanogram suggest
Retrocochlear pathology.
What activities are contraindicated in patients with a cochlear implant
Scuba and skydiving.
A patient with a SRT of 55 dB HL and a speech discrimination score of 64°/o at 75 dB HL has what kind of hearing loss
Sensorineural.
What are the 3 types of evoked OAEs
SFOAE (stimulus frequency); TEAOE (transient evoked); DPOAE (distortion product).
Which of these has no useful clinical application
SFOAE.
What are the stimuli used to obtain a speech reception threshold (SRT)
Spondees.
What do the peaks of the ABR represent
Synchronous neural discharge at various locations along the auditory pathway.
What is the Stenger’s test
Test to see if the patient is malingering; appropriate to administer if there is >20dB difference between ears in voluntary thresholds.
What does acoustic reflex delay measure
The ability of the stapedius muscle to maintain sustained contraction.
What is crossover
The attained responses represent the performance of the non-test ear rather than the test ear due to a large sensitivity difference between the ears.
Which part of the cochlea represents high frequency sounds
The basal end.
Which part of the auditory system is assessed by air conduction tests
The entire auditory system.
What is the frequency response of a hearing aid
The gain of the hearing aid across a range of frequencies.
What is the spondee/speech reception threshold
The lowest hearing level at which half of the words are heard and repeated correctly, followed by at least 2 correct ascending steps.
What is the definition of auditory threshold
The lowest level at which the patient can detect a sound 50% of the time.
What is the acoustic reflex threshold
The lowest stimulus level that elicits the stapedial reflex.
What is the plateau method in clinical masking
The non-test ear is masked by progressively greater amounts of sound until the threshold of the test ear does not continue to increase.
What is a nonlinear amplification system
The ratio of input to output is
What is interaural attenuation
The reduction of sound when it crosses from one ear to another.
What does the interwave latency reflect
The time necessary for neural information to travel between places in the auditory pathway; any pathology which interferes with this transmission will prolong the latency.
Which patients benefit most from nonlinear amplification systems
Those with a small range between their threshold for hearing and their loudness discomfort level (LDL).
How do prelingually deafened children with cochlear implants compare to those with multichannel tactile aids in open-set word recognition skills
Those with cochlear implants do better.
What is the basic function of assisted listening devices
To improve the signal-to-noise ratio at ear level by 15 - 20 dB in moderate noise and reverberation.
How is ABR most commonly used
To test newborns, difficult to test children, and malingerers.
What is fatigue
Tone decay or adaptation where continued acoustic stimulation changes the auditory threshold… suggestive of a lesion of the VI lith nerve or brainstem.
T/F: lnteraural attenuation values tend to be smaller for lower frequencies than higher frequencies
True.
T/F: The acoustic reflex threshold is absent in patients with middle ear disease
True.
T/F: Brainstem lesions may abolish the acoustic reflex without affecting the pure tone thresholds
True.
T/F: The ABR is unaffected by state of sleep or medications
True.
T/F: Females are twice as likely as males to demonstrate spontaneous OAEs
True.
T/F: ASSEP has little predictive value in for hearing levels in children with auditory neuropathy
True.
T/F: ASSEP cannot distinguish between cochlear and retrocochlear hearing loss
True.
T/F: Speech perception of prelingually deafened children who have had cochlear implants for 5 years is likely to be equal to or better than postlingually deafened patients
True.
T/F: The electrode of the cochlear implant is normally placed into the scala tympani
True.
T/F: Results of cochlear implantation in children with congenital inner ear malformations are comparable to those without malformations
True.
When is the interaural latency difference of wave V important
Used to document retrocochlear pathology when wave I is absent.
Which of the waves is the largest and most consistent
V.
What would the tympanogram look like in an ear with an interrupted ossicular chain
Very steep amplitude, high peak (type Ad).
What are the neural pathways of the acoustic reflex
VIII to the ipsilateral ventral cochlear nucleus to the trapezoid body to the motor nucleus of VII to VII to the ipsilateral stapedius. VIII to the ipsilateral ventral cochlear nucleus to the trapezoid body to the ipsilateral medial superior olive to the motor nucleus of VII to VII to the ipsilateral stapedius. VII I to the ipsilateral ventral cochlear nucleus to the medial superior olive to the contralateral motor nucleus of VII to the contralateral VII to the contralateral stapedius.
How is hearing threshold estimation performed using ABR
Wave V is tracked with decreasing sound intensity until it can no longer be observed.
When is wave I absent
When hearing loss exceeds 40 - 45 dB at higher frequencies.
What is the “half-gain rule?”
When programming a hearing aid, the gain for each frequency is determined by multiplying the patient’s hearing threshold at each frequency by 0.5.
When are interoctave frequencies tested (750, 1500, and 6000 Hz)
When successive octave thresholds differ by more than 20 dB.
When should masking be used
When the air conduction threshold of the test ear exceeds the bone conduction threshold of the non-test ear by a value greater than interaural attenuation.
Which of these is most appropriate for patients with substantially reduced dynamic ranges
Wide dynamic range compression.
