HL
Weird S***
See Eye
Anatomy
Hard
100

These are low-intensity sounds generated by the cochlea either spontaneously or in response to external sound stimulation. They are believed to be related to the process of cochlear amplification. Contraction of the outer hair cells generates displacement waves in the basilar membrane that travel back through the middle ear and emerge in the ear canal, where they can be detected by a sensitive microphone. They are valuable clinical indicators of cochlear health.

What are Otoacoustic emissions (OAEs)?

100

A surfer from Santa Cruz California (notorious for cold ocean water presents to clinic), name the pathology affecting the EAC.

What is surfer's ear or exostosis?

100

The number of turns in the cochlea

The cochlea is a snail-shaped structure that has a wide diameter at the base and narrows over 2.25 turns until it reaches its apex.

100

The mandibular condyle articulates with this structure of the temporal bone.

What is the glenoid or mandibular fossa of the temporal bone?

200

CDH23 and PCDH15 are calcium-sensitive cadherin proteins that connect tips of adjacent sterocilia and are essential for mechanoelectrical transduction. 

Mutations in these genes are known cases of this genetic syndrome (of which there are four types: Ia, Ib, II, and III) 

Cadherin 23 (CDH23) and protocadherin 15 (PCDH15), both members of the calcium-sensitive cadherin family of proteins, are key components of the hair bundle tip links in hair cells. These tip links, oriented obliquely, connect the tips of adjacent stereocilia and are essential for mechanoelectrical transduction. Several studies have identified mutations in the genes encoding CDH23 156 , 157 and PCDH15 158 , 159 as causes of Usher syndrome

200

Genetic mutations affecting prestin production (SLC26A4/PDS gene) lead to deficient mechanoelectrical transduction by outer hair cells manifesting as sensorineural hearing loss, a feature of this autosomal recessive syndrome.

What is Pendred syndrome? 

Causes euthyroid goiter and early HL.

200

Cochlear implants electrically stimulate these neurons of the cochlear nerve, bypassing the cochlea (and thus the most common location of SNHL).

A cochlear implant delivers sound information by electrically stimulating the primary afferent (spiral ganglion) neurons of the cochlear nerve, bypassing the cochlea where most sensorineural hearing loss (SNHL) occurs because of auditory hair cell loss or dysfunction. It is paired with an external sound processor, microphone, and power supply.

200

This named area is the apex of the cochlea at which the Scala vestibuli and Scala tympani communicate. 

What is the helicotrema? 

At the apex of the cochlea is the helicotrema, where the Scalae vestibuli and tympani communicate. 

200

Perilymph is found in the Scala vestibuli, Scala tympani, and internal spaces of the organ of Corti. It is high in sodium, low in potassium and communicates with CSF via which structure.  

Communicates with cerebrospinal fluid via cochlear aqueduct (perilymphatic duct). 


300

The average length of the cochlear duct in mm, according to Cummings. 

Both teams text Julliette guesses, closest wins. 

You will have 2 minutes to text an answer, you will not lose points for guessing. 

The cochlear duct length ranges from approximately 28.0 to 40.1 mm, with an average length between 33.13 and 34.0 mm. Cochlear duct length variability is relevant for cochlear implant electrode insertion depth and coverage of stimulable elements within the organ in rehabilitation of sensorineural hearing loss.

300

This is highly porous bone at the central core of the cochlea which allows the passage of auditory nerve fibers from the IAC to the hair cell synapses. 

What is the modiolus?

The central core of the cochlea is the modiolus, a highly porous bone that allows the passage of auditory nerve fibers from the internal auditory meatus to the hair cell synapses.

300

With regard to T1 and T2-weighting, contrast, and diffusion restriction, describe cholesteatoma enhancement patterns on MRI. 

Both teams have 2 minutes to come up with a response and text to Julliette. Must answer all 4 for points. Will NOT lose points for incorrect answer. 

Cholesteatoma has distinct imaging characteristics on magnetic resonance imaging (MRI). The lesion is isointense to hypointense on T1-weighted imaging, is intermediate on T2-weighted imaging, and does not enhance with addition of contrast medium. Most importantly, the lesion will restrict on diffusion-weighted imaging. MRI techniques for detection of residual cholesteatoma in lieu of staged surgery are evolving and promising.

400

Name the membranes that border the Scala media superiorly and inferiorly, must name both for points. 

The scala media is bordered:

Superiorly by the Reissner membrane

Inferiorly by the basilar membrane

Laterally by a portion of the outer cochlear wall

500

This area housed within the petrous portion of the temporal bone is the hardest bone in the human body, with hardness equivalent to ivory. 

What is the bony labyrinth consisting of the cochlea, semicircular canals, and vestibule?

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