Neuroanatomy Flashcards
Left hemifield projects to…?
Right hemifield projects to…?
RIght occipital lobe
Left occipital lobe
What part of visual feild does nasal retina see? waht about temporal retina?
Temporal half of visual field
nasal feild
Central scotoma. Location of leision?
macula degeneration / retina
Compete monocular vission loss. Location of leision?
optic nerve
bitemporal hemianopia. Location of leision?
optic chiasm
Contralateral homonomous hemianopia. Location of leision?
- Optic tract (from chiasm to lateral geniculate nucleus)
- Optic radiations
- Upper AND lower bank of the calcarine fissure (occipital lobe)
contralateral superior quadrantanopia? Location of leision?
Inferior meyers loops (optic raditasions) OR the lower bank of the calcarine fissure (occipital lobe)
contralateral inferior quadrantanopia? Location of leision?
superior meyers loops (optic raditasions) OR the upper bank of the calcerine fissure
Contralateral homonomous hemianopia with macular sparing. Location of leision?
PICA occlusion affecting both upper and lower banks of the calcerine fissure
Where is the lateral geniculate nucleus found?
Thalamus which is in the forebrain (superior to teh mid brain and hind brain)
Where do the inferior meyers loops / optic radiations travel? What about superior loops?
temporal lobe
parietal lobe
What does the MCA supply? superior and inferior division of MCA
MCA supplies the parietal lobe, frontal lobe and temporal lobe
- SUperior divisions mainly supply the frontal lobe (ioncluding Broccas area), inferior divisions mainly supply the temporal lobe, including wernikes area
What are the three sulci that define the temporal lobe?
Lateral sulvus seperates parietal lobe from temporal
-> superior temporal gyrus
superior temporal sulcus
-> middle temporal gyrus
inferior temporal sulcus
-> inferior temporal gyrus
What does the PCA supply?
The posteriomedial temporal lobe / inferior gyrus is supplied by the PCA
- The occipital lobe
- The midbrain
- splenium or corpus collosum (most posterior thickest part)
What does the ACA supply?
Mainly the parasagital regions of teh parietal and frontal lobes
- anterior corpus calosum
Describe the circle of willis? From bottom to top (in typical image representation)
Right and left vertebral arteries
- posterior inferior cerebelar arteries branch from vertebral arteries
Anterior spinal artery joint vertebral arteries just distal to vertebral artery union point into basilar artery
Bassilar artery has several branches
- anterior inferior cerebelar artery bilaterally
- then lots of pontine artery branches bilaterally
Basilar artery then splits like a palm tree into superior cerebellar artery bilaterally and PCA bilaterally.
the posterior communicating artery branches off from the PCA just distal to the origin of teh PCA from the bassilar. Posterior communicating and teh anterior communicating arteries froma circle with the PCA branching bilaterally from the middle of teh circle, and the ACA comiung from teh top of teh circle
What are the sections of the ACA?
A1 - precommunicating ACA
A2 - post communicating (between ACOM and callosocommunicating artery)
A3 - pre calossal
A4 - Supra callossal
A5 - post callosal
Describe the course of the PCA and the sections of the PCA?
basilar artery runs cranially in the central groove of the pons twards the midbrain
the PCA divides then wraps around the midbrain heading posteriorly towards the occipital lobe
P1 pre communicating - between origin and PCOM
P2 - from the PCOM around teh midbrain
P3
P4
P5 - terminal branches
Crossed signs in face and limbs = …?
Brain stem stroke
What are the parts of the brain stem?
Inferior to superior:
- Medulla oblongata
- Pons
- Midbrain
Thal is generally not considered part of the brain stem
What is part of the hindbrain?
Hinddbrain
- medulla oblongata
- Pons
- cerebellum
Midbrain
- midbrain
Forebrain
- everything else (inc cerebruim, thal, hypothal)
What is teh primary blood supply of the pons?
Basilar artery (pontine branches)
What is does the posterior inferior cerebellar artery supply?
Lateral medulla of brain stem
poterior inferior section of cerebellum
Blood supply of the medulla oblongata?
Lateral medulla - PICA
medial medulla - anterior spinal artery
- area between teh medial and lateral aspects supplied by direct branches from teh distal vertebral arteries
Lateral medullary syndrome features? Why are each of these features found?
- vertigo - vestibular mucleus found in lateral medulla
- Ipsilateral ataxia - inferior cerebellar peduncle
- Dysphagia / dysphonia - Nucleus solitaris (Vagal nerve nucleus)
- Ipsilateral facial numbness - spinal nuc of trigeminal nerve
- Horners syndrome - descending sympathetic fibres
- Contralateral limb weakness - anterior spinothalamic tract
Why does a pt with lateral medullary syndrome get contra-lateral limb numbness to pain and temperature?
Pain and temp carried in anterior spinothalamic tract
1st order sensory neuro from peripheries synapse in the spinal cord. then the second order neurons cross over AT THAT LEVEL, before ascending up the synapse in the thalamus