PBL B12 Weeek 6 Flashcards
What is Amaaurosis fugax?
Temporary loss of vision due to insufficient blood supply.
What is bruit?
Whooshing sound heard in auscultation due to turbulent blood flow.
What is the blood supply to the eye?
Opthalmic artery, a branch of the internal carotid. This is divided into an orbital and optical division.
What are the optical arteries?
Central retinal artery
Anterior ciliary artery
Short posterior ciliary artery
Long posterior artery
What does the anterior ciliary supply?
Rectus muscles
Sclera
What does the long posterior ciliary artery supply?
Iris, choroid and ciliary body.
What does the short ciliary artery supply?
Sclera, choroid and ciliary process. Forms a ring
What are the orbital arteries?
Lacrimal artery
Supraorbital artery
Anterior ethmoidal artery
Posterior ethmoidal artery
Medial palpebral artery
What does the medial palpebral artery supply?
Upper and lower eyelid.
What does the anterior ethmoidal artery supply?
Dura mater and nose dorsum.
What does the posterior ethmoidal artery supply?
Meninges
Posterior ethmoidal sinus
What does the supraorbital artery supply?
Upper eyelid
Frontal sinus
Levator palpabrae
What is the venous drainage of the eye?
Superior and inferior Opthalmic vein drain into the cavernous sinus.
What are the ascending tracts?
Sensory pathways
What are the descending tracts?
Motor pathway.
What is the control in the dorsal column pathway passing through the cuneate nucleus?
Control of muscles below T6.
What is the control in the dorsal column pathway passing through the gracilis nucleus?
Above T6
What are the unconscious sensory tracts?
Spinocerebellar
Spino-olivary tract
Spinoreticular tract
Spinotectal tract
What is the role of the spinocerebellar tract?
Unconscious propioception.
What is the role of the spinotectal tract?
Provides sensory information about visual stimuli to the superior colliucli.
What is the role of the spinoreticular tract?
Provides information from the spinal cord to reticular formation for awareness and emotional response to pain.
What are the pyramidal tracts?
Descending tracts from the cortex which includes:
Anterior corticospinal which remains ipsilateral at the pyramids to provide voluntary control of the trunk
Lateral corticospinal tract which devastates at the pyramids for fine voluntary motor control of limbs.
What are the extrapyramidal tracts?
Arise from the brain stem and include the:
Reticulospinal tract
Vestibulospinal tract
Tectospinal tract
Rubrospinal tract
What is the role of the rubrospinal tract?
Controls the flexor muscles.
What is dysphasia?
Dysphasia is a condition which affects your ability to produce and understand language. Consists of receptive and expressive dysphasia.
What is receptive dysphasia?
Issue with Wernicke’s area in the temporal lobe which affects understanding of speech, so there are nonsensical words.
What is expressive dysphasia?
Issue with Broca’s area in the frontal lobe which affects expression of speech. Understanding of speech is fine.
What is dysarthria?
Difficulty speaking because the muscles are weak.
Why would clear fluid leak out of nose and ears?
Leaking of Cerebrospinal fluid due to a tear in the dura mater.
What are the stages of ICP increases?
Stage 1 of ICP: Reduction in CSF and blood volume but ICP is normal
Stage 2 of ICP: ICP begins to increase
Stage 3 of ICP: High ICP causes cerebral perfusion pressure to decrease
Stage 4 of ICP: Necrosis of brain cells, brain begins to herniate against brain stem and cause respiratory arrest and death
