NB1 Exam Flashcards
What artery runs through the cavernous sinus?
ICA : The internal carotid artery
What are supplies the lateral cortex?
The middle cerebral artery
What area of the cortex processes the primary visual cortex?
Brodmann area 17
Retinitis Pigmentosa
Photoreceptors degenerate due to apoptosis, causing a gradual loss of vision
The Lesser Petrosa nerve is a branch of
CN IX Glossalpharyngeal nerve
What is the Innervation of the Posterior 2/3 of the Auricle(Pinna)?
C2-C3 The Great auricular nerve and the lesser occipital nerve C2.
Innervation of the Anterior 2/3 of the Auricle:
Auriculotemporal nerve(V3) w/ small contributions from CN VII and CN X.
Innervation of the External Acoustic Meatus:
Auriculotemporal nerve V3 EXCEPT a small area via CN X
CN X
Vagus Nerve
CN IX
Glossopharyngeal nerve
CN XI
Spinal Accessory Nerve
CN XII
Hypoglossal Nerve
Translucent membrane separating the external meatus from the middle ear:
Tympanic Membrane
Innervation of the External Surface of the Tympanic Membrane
CN V3 Auriculotemporal nerve except for a small area which is innervated by CN VII and CN X
Innervation of the Internal Surface of the Tympanic Membrane
Tympanic Plexus, CN IX
The three branches of CN V
V1 Ophthalmic
V2 Maxillary
V3 Mandibular Nerve which includes the auriculotemporal
Upon otoscopic exam the cone of light seen at 5’ o clock means Dr. is examining the________ ear
Right Ear
Upon otoscopic exam the cone of light seen at 7’ o clock means Dr. is examining the________ ear
Left Ear
Major Nerve of the Middle Ear:
Chorda Tympani
The three ossicles of the Middle Ear:
Malleus, Incus and Stapes
what structure connects the middle ear to the nasopharynx?
Pharygnotympanic tube
What two structures of the middle ear help to dampen sound?
The Stapedius muscle and the Tensor tympani tendon
Cells in the ear that are separated by the Posterior wall of the middle ear:
Mastoid ear cells
Describe The Floor of the Middle ear
Base of skull near jugular foramen
what structure runs on top of the facial nerve in the middles ear?
The Prominence of lateral semicircular canal
The oval window in the middle ear is located on the ______ wall.
Medial Wall
A nerve that branches from the anterior wall of the middle ear :
Lesser Petrosal Nerve a branch of CN IX
Which nerves make up the Tympanic Plexus?
Tympanic Nerve from CN IX and Internal Carotid plexus branches
Where does the Lesser petrosal nerve of the middle ear synapse?
at Otic ganglion
What nerve fibers does the tympanic nerve carry to the parotid gland?
Sensory afferents from the middle ear & Preganglionic parasympathetic
A branch of the facial nerve that runs between the Malleus and the Incus of the Lateral of the Middle ear:
Chorda Tympani Nerve
Preganglionic parasympathetics to lacrimal & mucosal glands via pterygopalatine ganglion
Greater Petrosal Nerve
Chorda Tympani is a branch of ___carries ________fibers from Anterior 2/3 of the tongue AND ____ ____ ___ innervation for submandibular and sublingual glands.
CN VII(Facial Nerve), Efferent preganglionic parasympathetic
What is the motor function of the Facial Nerve?
Carries Motor fibers to the stapedius, stylohyoid, posterior belly of digastric, muscles of facial expression
Middle ear is located in
the petrous portion of temporal bone
Anterior wall of the middle ear separates ____ from _____
Middle ear from internal carotid artery
The posterior Wall of the middle ear separates ___ from __
middle ear cavity from the internal jugular vein
The two branches of CN VIII of the Inner Ear:
- Vestibular branch( balance & equilibrium)
- Cochlear (hearing)
Clinical significance if there is a disruption of the ossicular chain:
Conductive Hearing Loss
Weber’s test completed and patient hears the sound more in the Right ear than the Left ear which ear is effected?
The Right Ear
Injury to the ossicles can lead to what kind of hearing loss?
conductive hearing loss
Clinical significance of the Round Window?
Cochlear Implant
Tympanostomy tubes can be placed in the ____ of the ear.
Tympanic membrane
A tympanic neurectomy occurs within the ______.
Tympanic plexus
A patient that comes in complaining of dry mouth and abnormal salivation may have an issue with their____
Chorda Tympani
Failure of the central cells of the metal plug to canalize:_______
Atresia of the External acoustic meatus
Remnants of the 1st pharyngeal groove present anterior to the auricle:
Auricular sinuses/ pits
Malformation of the 6 auricular hillocks, three from the 1st arch and three from the 2nd arch of mesenchyme tissue can lead to:
Auricular sinuses and cysts
The three germ layers of the tympanic membrane are
Ectoderm (1st groove)
Endoderm (1st pouch)
Mesoderm invades in between
Microtia
A rudimentary auricle
Which germ layer develops in to the external tympanic membrane?
Ectoderm of the 1st groove
The embryological origin of the internal tympanic membrane
Endoderm of the 1st pouch
What structure of the external ear becomes fully developed at age 9?
The External Acoustic Meatus
Ossicles develop by :
endochondral ossification
What ear bones are adult size at birth?
the auditory ossicles
What is the embryological origin of the Malleus, incus bones & Tensor tympani muscle?
1st arch cartilage and 1st arch
What structure of the middle ear developed from the 2nd arch cartilage?
The Stapes
What middle ear structure developed from the 2nd arch?
The Stapedius
____ ___ develops from the distal expanded part of the tubotympanic recess arising from the 1st pharyngeal pouch
The Middle Ear
The otic vesicle, derived from the ectoderm will give rise to the membranous labyrinth, describes development of __ ___ ___.
The Internal Ear
Mesenchyme surrounding this structure _____ _____ is activated to condense and differentiate into a cartilaginous ___ ___
otic vesicle, otic capsule
What makes up the bony labyrinth of the ear?
Cochlea, vestibule and semicircular canals
how are the bony labyrinths of the ear formed in embryological life?
The cartilaginous otic capsule undergoes ossification
Contraction of the tensor tympani and stapedius muscles that occurs in response to high intensity sound is:
The Attenuation Reflex
Innervation of the stapedius muscle:
CN VII
CN V innervates this muscle involved in the attenuation reflex
tensor tympani
Brodmann Area for the Primary Auditory Cortex
Brodmann Area 41 & 42
The PNS of the Auditory Pathway is innervated by ______
CN VIII Vestibulo-cochlear nerve aka auditory nerve
The auditory nerve enters the brainstem at the level of the ____ -_____ _____.
Ponto-medullary junction
Disruption of the conduction of sound vibration through the external auditory canal and middle ear can lead to:
Conductive Hearing Loss
Sensorineural Hearing loss can occur when
there is a lesion of the Organ of Corti or the Vestibo-cochlear nerve(Auditory Nerve, CN VIII)
Vestibular Schwannoma causes what type of hearing loss?
Sensorineural
Meniere’s Disease causes what type of hearing loss?
Sensorineural
Angular acceleration in the ear is detected by:
Semicircular canals
A physiological nystagmus that happens during head rotation:
Vestibulo- ocular nystagmus
Rhythmically alternating eye movements:
Nystagmus
The SLOW phase of a Nystagmus is driven by:
The vestibulo-ocular reflex
A nystagmus is defined by the _____ phase
Fast phase
Accumulation of prion proteins w/ Beta - pleated sheets
Creutzfeldt-Jakob disease
Elevated VMA in urine is due to breakdown of _____ neurotransmitter
Norepineprhine or Epinephrine
Excessive Dopamine Metabolism can lead to ___ in urine
HVA
GABA transaminase is responsible for
degradation of GABA
Tympanic Membrane is innervated by the _______ nerve which provides sensory innervation.
Glossopharyngeal nerve CNIX
Where are Vestibular nuclei found?
In the postero-lateral medulla.