Theme 1: Anatomy Flashcards
what artery does the pterion overly?
middle meningeal artery- vulnerable to rupture causing extradural haemorrhage
what is the bregma and lambda?
the bregma is the location of the anterior fontanelle in neonates
the lambda is the location fo the posterior fontanelle
which cranial nerves exit vis the superior orbital fissure?
CNIII- oculomotor
CNIV- trochlear
CNV1- opthalmic branch of trigeminal
CNVI- abducens
which cranial nerve passes through the cribiform plate?
CNI- olfactory nerve
which foramina do the maxillary and mandibular branches of CNV pass through?
CNV2 (maxillary)- foramen rotundum
CNV3 (mandibular)- foramen ovale
which cranial nerves pass through the internal acoustic meatus?
CNVII- facial nerve
CNVIII- vestibulocochlear
which cranial nerves pass through the jugular foramen?
CNIX- glossopharyngeal
CNX- vagus
CNXI- accessory spinal nerve
which cranial nerve passes through the hypoglossal canal?
CNXII- hypoglossal canal
where does the anterior cerebral artery supply?
the medial surface of the cerebral hemisphere- medial frontal and parietal lobe and the cignulate gyrus and corpus callosum
which artery supplies the anterior circulation of the brain?
internal carotid artery
which artery supplies the posterior circulation of the brain?
the vertebral arteries which are branches of the subclavian
where does the middle cerebral artery supply?
the majority of the lateral cerebrum- lateral frontal, paretial and temporal lobes
which artery is formed by the union of the two vertebral arteries?
the basilar artery
where does the posterior cerebral artery supply?
inferomedial temporal lobe
occipital lobe
how is cerebral blood flow controlled?
CBF is controlled by auto regulation:
if cerebral perfusion pressure increases vasoconstriction occurs decreasing CBF
if CPP decreases vasodilation occurs increasing CBF
only works within the autoregulatory limit- outside this CBF is dependant on MAP
where is brocas area and what is its function?
located in the inferior frontal gyrus. supplied by MCA
involved in the motor programming of speech (expressive component of language)
where is wernickes area and what is its function?
located in the superior temporal gyrus- supplied by MCA
involved in language comprehension (receptive component of language)
what is the arcuate fasiculus?
bundle of association fibres connecting wernickes and brocas areas
describe the pathway involved in the processing of speech?
information from the primary auditory cortex (or primary visual cortex) is sent to the association cortex. from there information is sent to wernickes area and then via the arcuate fasiculus to brooks area. from here fibres project to motor cortices
what is the cause and features of brocas aphasia?
lesion to inferior frontal gyrus
features- slow speech, word finding difficulties, impaired repetition, normal comprehension
what is the cause and features of wernickes aphasia?
lesion to superior temporal gyrus
features- impaired comprehension, addition of extra/made up words to sentences, normal fluidity of speech
what is the cause and features of conduction aphasia?
lesion to arcuate fasiculus
features- impaired repetition, insertion of words that sound similar but are not correct, comprehension and fluidity intact
what are the stages involved int the production of speech?
- respiration- exhalation required for speech
- phonation- air passed through closed vocal folds, vibrations along the vocal folds allow sound production
- resonance- modification of sound in the pharyngeal/oral/nasal cavity
- articulation- further modification of sound using other structures
what are active and passive articulators?
active articulators include the tongue, lower lip lip and soft palate- they move
passive articulators include the upper lip, teeth, alveolar ridge and hard palate- they do not move but provide a fixed point for other structures to move against
what are the cranial nerves and their fibre types?
CNI- olfactory- sensory CNII- optic- sensory CNIII- occulomotor- motor CNIV- trochlear- motor CNV- trigeminal- both CNVI- abducens- motor CNVII- facial- both CNVIII- vestibulocochlear- sensory CNIX- glossopharyngeal- both CNX- vagus- both CNXI- spinal accessory-motor CNXII- hypoglossal- motor
which cranial nerves have parasympathetic function?
CNIII- occculomotor- pupil reflex
CNVII- facial- lacrimal and salivary glands
CNIX- glossopharyngeal- parotid gland
CNX- vagus- thorax and abdomen
where do the cranial nerves originate?
cerebrum- CNI and CNII
midbrain- CNIII and CNIV
pons- CNV, CNVI, CNVII, CNVIII
medulla- CNIX, CNX, CNXI, CNXII
what does the glossopharyngeal nerve innervate?
special senses- taste (post 1/3)
general sensory- post. tongue, oropharynx
motor- stylopharyngeus
parasympathetic- parotid gland
also innervates the carotid body and sinus
what does the vagus nerve innervate?
general sensory and motor- pharynx and larynx
parasympathetic- thorax and abdomen
what does the spinal accessory nerve innervate?
SCM and trapezius
what are the branches of the external carotid artery?
superior thyroid ascending pharyngeal lingual facial occipital posterior auricular maxillary superficial temporal (some anatomists like freaking out poor medical student)
where do the divisions of the trigeminal nerve come together?
trigeminal ganglion
where do fibres from the trigeminal sensory nucleus project to?
second order neurones decussate and ascend in the trigeminothalamic tract to the ventral posterior medial (VPM) nucleus of the thalamus. they then project to the somatosensory cortex
which nerve gives off the greater petrosal nerve?
the facial nerve
where does the facial nerve exit the facial canal?
the stylomastoid foramen
what are the 5 terminal branches of the facial nerve?
temporal zygomatic buccal marginal cervical
which muscle raises the eyebrows?
frontalis portion of occipitofrontalis
which muscle closes the eyes tightly?
orbicularis oculi
which muscle blows out the cheeks?
buccinator
which muscle closes the lips?
orbicularis iris
which muscle allows you to grimace?
platysma
what is the branch of the facial nerve that provides taste inner to the anterior 2/3 of the tongue?
chorda tympani
what is trigeminal neuralgia?
episodic severe unilateral sharp shock like pain in the V2/V3 distribution which lasts for seconds/minutes
caused by nerve compression
precipitated by light touch, washing face, cold wind etc.
what are the paranasal sinuses?
maxillary sinus- lateral nasal cavity
sphenoidal sinus- superoposteriorly to the nasal cavity
frontal sinus- on top of the nasal cavity between the eyebrows
ethmoidal sinus- posterior on top of the nasal cavity
where do the paranasal sinuses drain?
superior meatus- drains the posterior ethmoidal air cells and the sphenoid sinus
middle meatus- the rest of the sinuses (maxillary, frontal, ethmoidal) drain here via the hiatus semilunaris
where does the nasolacrimal duct drain into the nasal cavity?
the interior meatus
where do the blood vessels of the nose anastomose?
littles area
where do the anterior and posterior ethmoidal arteries branch from and what do they supply?
the ophthalmic branch of the internal carotid
they supply the lateral wall of the nasal cavity and give septal branches to the medial wall
what are the branches of the maxillary artery that supply the nasal cavity?
sphenopalatine artery
greater palatine artery
what are the branches of the facial artery that supply the nasal cavity?
lateral nasal artery
superior labial artery
where does the nasopalatine nerve branch from and how does it enter the nasal cavity?
the pterygopalatine ganglion
it passes through the sphenopalatine foramen
what is turbinate hypertrophy?
swollen nasal conchae causing obstruction