Head & Neck Anatomy Flashcards
What are the borders of the anterior and posterior triangle of neck?
Anterior: midline of neck, anterior border of SCM and lower border of mandible
Posterior: Posterior border of SCM, anterior border of trapezius & medial 1/3rd of the clavicle
What are the 4 sub triangles of the anterior triangle and what are their borders & contents?
- Submental
Borders: neck midline, hyoid bone & anterior digastric
Contents: lymph nodes - Submandibular
Borders: anterior & posterior belly of digastrics & mandible
Contents: lymph nodes, submandibular gland & facial artery/vein - Carotid
Borders: superior belly of omohyoid, posterior belly of digastric & SCM
Contents: CCA, IJV, CNX & CNXII - Muscular
Borders: neck midline, hyoid bone, superior belly of omohyoid & SCM
Contents: infrahyoid muscles (omohyoid, sternohyoid, thyrohyoid & sternothyroid) pharynx, thyroid & parathyroid glands
What is the innervation of omohyoid muscle?
Anterior rami of C1-3 (ansa cervicalis)
What are the external muscles of the tongue & their innervation?
Genioglossus
Hyoglossus
Styloglossus
Palatoglossus
All innervated by CNXII except palatoglossus (CNX)
What 3 nerves pass the submandibular gland?
Lingual nerve (CNVc): supplies sensation to ant. 2/3rd of tongue
Hypoglossal nerve (CNXII): supplies extrinsic muscles of tongue
Marginal mandibular nerve (CNVII): motor innervation to lower lip/chin (depressor labii inferioris, depressor anguli oris & mentalis)
What kind of secretion does submandibular gland produce?
Mixed serous and mucinous
(sublingual produces predominantly mucous and parotid produces serous watery saliva rich in enzymes)
What level does the carina bifurcate?
T4-5
If you ligate facial artery will you get necrosis of the muscles it supplies?
No because of anastomosis with lingual artery (ECA)
What does CNIX supply?
Sensory: oropharynx, carotid body/sinus, posterior 1/3rd of tongue, middle ear & eustachian tube
Special sensory: taste to posterior 1/3rd of tongue
PS: parotid gland via otic ganglion
Motor: stylopharyngeus muscle (elevates larynx/pharynx)
What nerve passes just anterior to external carotid artery?
CNXII
Where does the ICA enter the skull? What branch does it given off before ACA/MCA?
Carotid canal in petrous part of temporal bone (also contains SIDE - sympathetic plexus, ICA, deep petrosal nerve & emissary veins)
Opthalmic artery, posterior communicating artery and anterior choroidal artery
How do you treat an intracranial aneurysm? What type of haemorrhage occurs if it ruptures?
Clipping or coiling (IR)
Subarachnoid haemorrhage (SAH)
What are the signs of an MCA infarct?
Contralateral hemiplegia/hemisensory loss of lower 1/2 face
Contralateral hemiplegia/hemisensory loss of UL/LL (UL > LL)
Aphasia
What is the course of the vertebral artery?
Enters skull via foramen magnum
Crosses transversely across posterior arch of atlas (C1)
Inside skull the 2x arteries pass up/forward/medially in subarachnoid space to reach anterior medulla
Unite together at lower pons to form basilar artery
Name all dural venous sinuses and how they run.
4 unpaired:
1. Superior sagittal (falx cerebri): drain sup. cerebral vein & diploic/emissary veins and runs in falx cerebri
2. Inferior sagittal (falx cerebri): drains medial cerebral hemisphere
3. Straight sinus (tentorium cerebelli): drains great cerebral vein & inferior sagittal sinus
4. Occipital (inner surface of occipital bone): drains internal vertebral venous plexus
Confluence of sinuses = sup. sagittal, straight & occipital
6 paired
1. Sphenoparietal (lesser wing of sphenoid): drains sup. cerebral veins and draining into cavernous sinus
2. Sup. petrosal (petrous part of temporal bone) : drains cerebellar veins, inf/ cerebral vein, labrynthine veins & cavernous sinus draining in to sigmoid sinus
3. Inf. petrosal (between petrous temporal bone and inf. petrosal sulcus): drains cavernous sinus and goes into sigmoid sinus
4. Transverse (inner aspect of occipital bone in groove): drains confluence of sinuses into the sigmoid sinus
5. Sigmoid (post. cranial fossa floor): drains transverse & inf. petrosal sinus into IJV
6. Cavernous sinus (either side of sellca turcica of sphenoid in middle cranial fossa): drains opthalmic veins, central retinal vein, sphenoparietal sinus, sup. middle cerebral vein & pterygoid plexus & empty into sup/inf petrosal sinuses
Describe the flow of CSF.
Produced in choroid plexus of ventricles & flows from:
Lateral ventricles
Foramen of Monro
Third ventricle
Cerebral aqueduct of Sylvius
4th ventricle
Foramen of Magendie (medial) & Luschka (lateral)
Subarachnoid space
Reabsorbed by arachnoid granulations via superior sagittal sinus
MRI brain lesion. Differentials?
Astrocytoma
Glioblastoma
Ependymoma
Brain mets
Abscess (but more often ring enhancing)
What are the contents of
a) Optic canal
b) SOF
c) Foramen rotundum
d) Foramen ovale
e) Foramen spinosum
a) Optic nerve, opthalmic artery & sympathetic fibres
b) CNIII, IV, Va (lacrimal, frontal & nasociliary branches), VI & opthalmic veins (sup/inf)
c) CNVb
d) Otic ganglion, CNVc, accessory meningeal artery, lesser petrosal nerve & emissary veins
e) Middle meningeal artery & meningeal branch of CNVc
What is the motor innervations of CNVc?
Muscles of mastication (masseter, temporalis, lateral & medial pterygoids)
Mylohyoid
Anterior belly of digastric
