Pons Flashcards
What is a major landmark of the pons?
Pontine protuberance
The base of the pons is the ______ while the dorsal part of the pons is mostly ______
base - pontine protuberance
dorsal - tegmentum
What two structures are in the Facial colliculus?
- Nucleus of CN 6
2. Motor root of 7
What is the bridge between the pons and the cerebellum?
Middle cerebellar peduncle
What two cranial nerves are found in the low pons?
CN 6
CN 7
What separates the pontine protuberance from the tegmentum?
Medial lemniscus
corticobulbar tracts innervate the ____ while the corticospinal tracts innervate the ____
corticobulbar - face
corticospinal - body
What structure in the pons is important for fast horizontal conjugate eye movements?
PPRF (paramedian pontine reticular formation)
What CN and nucleus are responsible for tearing?
CN 7
Superior salivatory nucleus
What are the two roots of the facial nerve?
Motor root
Nervus intermedius
the motor nucleus of CN VII innervates the ____ and _____
- face
2. stapedius (middle ear)
The facial nerve enters the _____ _____ _____ and exits through the ______ ______
internal auditory meatus
stylomastoid foramen
CN VII ____ the eye while CN III ____ the eyes
CN VII - closes
CN III - opens
The superior salivatory nucleus innervates the _____ gland while the inferior salivatory nucleus innervates the ____ gland
superior - lacrimal
inferior - parotid
The greater petrosal nerve carries _____ fibers while the deep petrosal nerve carries ____ fibers
greater petrosal - parasympathetic
deep petrosal - sympathetic
Does CN VII synapse with the Geniculate ganglion?
Fuck that shit, it just runs through it
What brainstem nucleus does the greater superficial petrosal nerve originate?
Superior salivatory nucleus
chorda tympani runs below the __________
Greater superficial petrosal nerve
What cranial nucleus is responsible for general sensation behind the ear?
Spinal trigeminal nucleus through CN 7
Corticobulbar lesions cause _____ facial weakness while CN VII lesions cause _____ facial weakness
corticobulbar - central (UMN)
CN VII - peripheral (LMN)
Corticobulbar tracts synapse with all _____ cranial nuclei
motor
Why don’t parasympathetics get coricobulbar drive?
because they don’t innervate striated skeletal muscle
upper face LMNs get _______ corticobulbar innervation while low face LMNs get _______ corticobulbar innervation
upper face - bilateral innervation
lower face - contralateral innervation
Does the GSPN carry pre or post ganglionic nerve fibers?
pre
The Pons is important for _____ conjugate eye movements while the Midbrain is important for _____ conjugate eye movements
pons - horizontal eye movements
midbrain - vertical eye movements
What are the associated symptoms of a lesion of the sixth nerve in the pons?
- Horizontal gaze palsy
- contra spastic hemiparesis
- CN 7 palsy (“long tract” signs)
What are the associated symptoms of a lesion of the sixth nerve in the subarachnoid space?
- LMN signs of CN 7
- no facial numbness or body weakness
* cuz CN 6 and 7 reside in subarachnoid space*
What could cause a 6th nerve lesion in Dorello’s canal?
Mastoiditis or metastatic bone cancer
What cranial nerves are in the cavernous sinus?
3, 4, V1, V2, 6
not V3
What are three characteristics that indicate a CN 6 lesion in the orbit?
- CN 6 palsy
- proptosis
- RAPD
How long does it take for an isolated vasculopathy to recover after temporary ischemia and demyelination?
90 days
The frontal eye fields is located in the ______ lobes and helps to generate saccades to the ______ side
frontal lobes
saccades to the opposite side
What is a saccade?
rapid eye movement from one fixation point to another
A right MLF lesion would lead to an INO on what side?
the right
If a patient is experiencing a left, right, or binocular INO (internuclear Ophthalmoplegia) but is able to converge, what part of the brain is ok and what is damaged?
midbrain is ok
pons is damaged
