Cross-sectional Anatomy Flashcards
What does CT measure?
Tissue density
What does MRI measure?
Hydrogen content
What does CT use to generate an image?
X-ray radiation
What does MRI use to generate an image?
Radiowaves and magnetic fields
Which type of imaging generates images in trains-axial slices and uses 3D image data to reconstruct this on other planes?
CT
Which type of imaging can simultaneously generate images from several planes and angles?
MRI
On which type of MRI sequence does CSF show up as bright?
T2-weighted
On which type of MRI sequence does white matter look lighter than grey matter?
T1-weighted
In T2-weighted imaging, which type of matter shows up as darker?
White matter
Which anatomical plane looks at the brain from the side?
Sagittal
Which anatomical plane looks at the brain from above?
Axial
Which anatomical plane looks at the brain from behind?
Coronal
What does lateral describe?
Structures away from the midline
What name do you give regions close to the midline?
Medial
What does dorsal relate to?
The upper side
What structure lies on the dorsal side of the brain stem?
The cerebellum
What does ventral relate to?
The underside
What structure lies on the ventral side of the brainstem?
The pons
What is the term for the posterior structures?
Caudal
What is the term for anterior structures?
Cranial/rostral
What are the four main lobes?
Frontal, parietal, temporal, and occipital
What are the two additional medial lobes?
The insula and the limbic lobe
What are gyri?
Bumps
What are sulci?
Dips
What separates the frontal and parietal lobes from the temporal lobe?
The Sylvian fissure (lateral fissure/sulcus)
What is the inferior frontal gyrus associated with?
Language expression and articulation (Broca’s area)
Which structure is shaped like an M and lies above the front of the Sylvian fissure?
The inferior frontal gyrus
What lies above the inferior frontal. gyrus?
The superior frontal gyrus
What is the name of the dip before the central sulcus?
The precentral sulcus
What separates the frontal from the parietal lobe?
The central sulcus
What area is located immediately before the central sulcus?
The motor area (precentral gyrus)
What area is located immediatly after the central sulcus?
The sensory cortex (postcentral gyrus)
Where is Broca’s area?
The inferior frontal gyrus, typically on the left
Name the two main areas of the lateral parietal lobe?
The postcentral gyrus (sensory cortex) and the inferior parietal lobule
Name the two main gyri of the inferior parietal lobule.
The supramarginal gyrus and the angular gyrus
What is the angular gyrus associated with?
Semantic and phonological language, word and sentence comprehension, reading and writing, and number processing
Where is Wernicke’s area located?
The posterior region of the superior temporal sulcus, typically on the left
What are the three divisions of the lateral temporal lobe?
Superior temporal gyrus, middle temporal gyrus, and the inferior temporal gyrus
What is Wernicke’s area associated with?
Language reception and comprehension
What is the heart shaped bump at the top of the temporal lobe?
Heschl’s gyrus (primary auditory cortex)
Where is the primary auditory cortex?
On Heschl’s gyrus, at the top of the temporal lobe
Where is the insula located?
In front of the primary auditory cortex
(lateral temporal lobe but more medial than temporal gyri)
What structure looks like a hook in between the lateral and medial sagittal plane?
The precentral gyrus
What are the two main sulci of the medial occipital region?
▪️ Parieto-occipital sulcus
▪️ Calcarine sulcus (divides OL, where PVC is)
What are the two main regions of the medial OL?
▪️ Cuneus
▪️ Lingual gyrus
What does the hand knob sign indicate on an axial view of the brain?
The central sulcus
Which is thicker, the precentral gyrus or the postcentral gyrus?
Precentral
What is the precentral gyrus?
The primary motor area - initiates voluntary movement through the corticospinal tract
How can you spot the supplementary motor areas (SMA) and what does it do?
On the posterior end of the superior frontal gyrus when viewing the brain axially
▪️ Planning, coordinating and initiation of movement
▪️ Language, learning new sequential movements, WM
Where is the pre-supplementary motor area and what does it do?
▪️ Infront of the SMA
▪️ Language, learning new sequential movements
▪️ Working memory
What area is at the point where the superior frontal gyrus, middle frontal gyrus and precentral gyrus meet?
Premotor cortex
(integrates auditory, visual, and somatosensory stimuli for movement related tasks - “mirror neurones?”)
Where is the dorsolateral prefrontal cortex?
At the anterior end of the middle frontal gyrus
Where is the fusiform gyrus?
On the occipito-temporal gyri (lateral)
What does the fornix connect?
The hippocampus and the mammillary bodies
(with septal nuclei, nucleus accumbens, and anterior nuclei of thalamus in the middle
What is the anterior commissure?
A small structure (collection of nerve fibres) off the anterior part of the fornix which connects the hemispheres
What are the posterior rising parts of the fornix?
The crus
What are the anterior downward parts of the fornix, joining onto the mammillary bodies?
The columns
What structure is found at the bottom of the caudate nucleus curve?
The amygdala
What are the white matter in between the putamen, GPi and GPe, and when are they most visible?
The medullary lamina
Best seen when pathology e.g., inflammation, oedema
What is the lentiform nucleus?
The putamen and globus pallidi
What is in the middle of the two cerebellar hemispheres?
The median/cerebellar vermis
What are the lines connecting the brainstem and the cerebellum?
The cerebellar peduncles
(3 on each side - superior, middle, and inferior)
