head and neck cheat sheets pdf
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Head
Orbitomeatal plane- inf margin of eye socket & sup external acoustic meatus in same horizontal plane
Cranium: 1)neuralcranium (vault/ covers brain, cranial meninges, prox parts of cranial nerves, vasculature of brain), has calvaria & basicranium.
2)viscerocranium(facial skeleton, 15 irreg bones)
Neuralcranium: 8 bones united by interlocking sutures(4midline: frontal, occipital, ethmoid, sphenoid, 2 bilateral pairs: temporal, parietal)
Facial Aspect of Cranium
Frontal bone (forehead), has supra-orbital notch to drain sinus
Zygomatic (cheek), has piriform aperture(ant nasal opening, w/ curved nasal conchae or lateral wall) Maxillae has infra-orbital foramen Orbits has sup &inf orbital fissures & optical canals
Lateral Aspect of Cranium
Mandible- U shaped, lower jaw, has alveolar processes for Mandibular Teeth ( Head , Ramus Angle, body) Maxillae- upper jaw maxillary teeth Head- in orbitomeatal plane Zygomatic arch- formed by temporal & zygomatic bone Pterion (Wing): H shaped formation of sutures (unite frontal, parietal, temporal, and sphenoid bones), overlies meningeal vessels in calvaria External Acoustic Meatus (Ear canal)Tympatic membrane (eardrum) Mastoid Process- apex of temporal bone/ Attachment for Sternocleidomastoid muscle
Occipital Aspect of Cranium
Occipital, parietal, mastoid parts of temporal bones External Occipital Protuberance (easily palpable) Superior Nuchal Line (marks sup neck limit) Lamda- felt like depression, junction of sagittal & lambdoid sutures
Cranial Base Inferior View (Basicranium)
2 Occipital Condyles- large protuberances where cranium articulates w/ vertebral column Atlas C1 External Opening of Carotid canal- where int carotid enter to supply brain External Surface of Basicranium: Alveolar Arch of Maxillae, Hard Palate( palantine process of maxillae & Horizontal Plates of Palantine Bones)
Choanae (post nasal aperture), Vomer (thin flat bone of Nasal Septum, separates choana)
Internal Surface: has bowl shaped floor w/ 3 large depressions
Anterior cranial fossa: has orbital plates- support frontal lobe of brain, crista galli (cocks comb)- median ridge on each side of Cribiform platEthmoid (axons of olfactory nerves CN1)
Middle: has Sella Turcica/ Turkish Saddle surround by Ant &Post Clinoid Process, hypophysial fossa/ Pituitary Fossa Posterior: largest & deepest, has Cerebellum, Pons, Medulla. At temporal base has Jugular Foramina (contains Sup Internal Jugular v),
Hypoglossal canals (has CN XII- motor to tongue)
Scalp-5 layers, first 3 move as 1 unit like wrinkling
fr sup nuchal lines on occipital bone to Supra Orbital margins of frontal bone & over zygomatic bone laterally . 1. Skin-glands & hair follicles, arterial sup
&venous/lymphatic drainage. 2. CT- vascularized, 3. Aponeurosis- muscle covers calvaria, attach to occipitofrontalis muscle, 4. Loose CT- sponge like w
potential spaces may distend w/ fluid fr injury infection, 5. Pericranium-dense CT form external periosteum of neurocranium
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Cranial Meninges- 1. Dura mater: periosteal (outer balloon)is internal surface of calvaria & meningeal (inner balloon) is cont @ foramen magnum w
dura covering the spinal cord. 2. Arachnoid: Avascular, thin filled w/ CSF. 3. Pia: very vascularized, cover brain
Innervated fr Trigeminal (CN V)N. Headache=pain fr dura(cervical n/trigeminal n), around dural venou sinuses &Meningeal a. Causes: distention of
scalp/meningeal vessels..after lumbar spinal puncture, CSF removedbrain sags &pull on superior dura.
Subarachoid=real space has CSF, Arachnoid Trabecular Cells, Cerebral a&v (drain intoSSS). Epidural & Subdural are potential spaces.
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Dural Infoldings (for compartments): 1. Falx cerebri- lies in longitudinal cerebral fissure & separates L from R cerebral hemispheres, 2. Tentorium
Cerebelli- separates occipital lobes from cerebellum, 3. Falx Cerebelli, 4. Diaphragm sellae- forms roof over hypophysial fossa & covers the pituitary gla
pp get oxytocin (hormone of love) &vasopressin (antidiuretic hormone for fluid retention) fr hypothalamus
Diaphragm Sellae: forms a partial roof over hypohysial fossa and covers the pituitary gland (receives oxytocin and vasopressin)
Dural Venous Sinuses- endothelial lined spaces btw periosteal & meningeal layers of dura. Veins fr brain surface & bone (diploe) drain into
sinusesint jugular v. (Superior sagittal sinus receives sup cerebral vein)Sigmoid Sinus- S shaped, turns inferiorlyjugular foramencont as Int Jugula
vein
Arachnoid granulation: collection of arachnoid villi fr arachnoid that protrude thru meningeal layer of dura materdura venous sinus &lateral venouslacunae. Function: transfer CSF to venous system. Arachnoid trabeculae are CT that passes btw arachnoid &the pia.
Basilar Plexus: communicates inf. w/ internal vertebral venous plexusazygos v.SVC
Neurovasculature of Cranial Meninges: veins of dura accomp. Meningeal a. Maxillary a. enters middle cranial fossa thru Foramen Spinosum &
become Middle Meningeal a. Pterion overlies branches of middle meningeal vessels. (Damage=life threatening)
Epidural hemorrhage=epidural hematoma(concave)brief concussionlucid interval.
Subarachnoid hemorrhage(extravasation of blood fr rupture of Saccular Aneurysm-saclike dilation of a). No lucid interval, no brief concussion
Scalp Injuries: infection in loose CTcranial cavity via EMISSARY V (drain blood away fr scalp to sinuses). Black eye results fr leaks thru aponeurosis
layer. Diploic v- in cranial& drain blood away from bones into sinuses.
Brain: 1. Forebrainmotor control- cerebral cortex (thinking), thalamus (sensory), hypothalamus (hunger/thirst/sex/temp/pituitary secretion
2. Midbrainawareness & visual (filters & evaluates motor & sensory neuron signals). Rostral (toward head) part
3.Hindbrain- cerebellum (coordinates motor acts), pons (pathway for motor & sensory neuron signals), medulla(regulates respiration, heart rate, diges
Regions of Cerebral Cortex: Frontal &Temporal Lobe- motor control, smell. Parietal lobe: sensory. Occipital Lobe: receives & process visual info. Als
Gyri (folds), Sulci (grooves), Fissures (Cleft)
Cranial N. 1. Olfactory (smell), 2. Optic, 3. Oculomotor (movement of eye), 4-Trochlear Nerve (SEN)(motor nerve innervates the superior oblique mus
th eye) 5. Trigeminal (ophthalmic, maxillary, & mandible areas), 6. abducen nerve (SEN) controls movement lateral rectus muscle of the eye) 7. Facial,
8. Acoustic (hearing & equilibrium), 9. Glossopharyngeal (sensation of pharynx & post 1/3 of tongue), 10. Vagus (sensory to thoracic & abdominal visce
11. Accessory (movement of head &neck) arises fr cervical spinal cord & somatic motor to trapezius &sternocledomastoid , 12. Hypoglossal (tongue)
Ventricular System- fr lumen of embryonic neural tube. 2 lateral opened into mid 3rd
via the interventricular foramina. 3rd
is concavity btw R&L
diencephalon. 4th
post to pons & medullatapers into spinal cord. Cerebral aqueduct- narrow channel which connects 3rd
&4th
ventricles.
CSF fr Choroid Plexus. Drains fr 4th
ventricle thru Median Aperture & Lateral Apertures into Cisterns (~ subarachnoid)
Vasculature: internal carotid a &vertebral a supply brain brachiocephalic a.
Vertebral a (fr. Subclavian a.)foramen magnum Basilar a.
Circle of Willis aka Cerebral Arterial Circle (backup system) @base of brain: 2 vertebral & 2 internal carotid aEmbolism(blockage)/ thrombosis (clots)/
cerebral/subarachnoid hemorrhageIschemic Stroke
circle of willis: circle of arteries that supply blood to the brain
Cerebral Veins drainsnearest dural venous sinusesInternal Jugular V
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Face- No distinct deep fascia, Muscles of face are in Subcut. Tissue
Muscle Name Origin Insertion Action
Frontal belly Epicranial aponeurosis Skin& sub tissue of eyebrows +forehead Elevate eyebrows & wrinkle forehead
Scalo ( surprise /curiosity)
Occipital belly Superior nuchal line Epicranial aponeurosis Retracts scalp, effect of frontal belly
Orbicularis oculi (orbital sphincter) Medial orbital margin Skin around margin of orbital Closes eyelids, orbital part tightly
Orbicularis oris (oral sphincter) Med maxilla &mandible Mucus membrane of lips Closes mouth, kissing, blowing,..
Buccinator (cheek mus.)
Trumpeter active in smiling, sucking,
whistling, & blowing
Mandible Orbicularis (angle of mouth..modiolus) Keep food out of oral vestibule
Resists distension when BLOWING
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Fr Facial nerve (CN VIII)- Motor Innervation.
Trigeminal Nerve (CN V)- Sensory
Cutaneous (Sensory) Nerve Name Origin Course Distribution
Supra-orbital Branch fr bifurcation of frontal n, in
middle of orbital roof
Anteriorly along roof of orbit,
emerging via supra- orbital notch
Mucosa of frontal sinus
Infra-orbital Fr CNV2 via the inf. Orbital fissure Infra-orbital groove in orbital floor Mucosa of maxillary sinus/
maxillary teeth
Arteries of Face & Scalp: w/in CT in scalp, btw skin @ epicranial aponeurosis..
External Carotid aFacial a (inferior border of mandible)..provides major arterial supply to face.
Lymphatic Drainage: Only parotid/buccal region has lymph nodesupf lymph node (@junc of head &neck)deep cervical lymph nodes along IJV
Parotid Gland (salivary gland), has parotid sheath, btw ramus of mandible &mastoid process. Parasympathetic of CN9
EYE
Orbit - pyramidal bony cavity w/ square base (orbital opening, anterolaterally). Apex- posteromedially @optic canal in sphenoid.
Eyelids keep cornea moist by speading lacrimal fluid. Palpebral conjunctiva: internal transparent epithelial mucous membrane covering of eyelid,
continuous w/ bulbar conjunctiva (loose & wrinkled over the sclera..has blood vessels). Together, bound the conjunctival sac (mucosal bursal space).
Lacrimal Apparatus: CN7(parasym)Lacrimal. glandsL. fluidL. ductsconjunc sac
Tears w/ dust is accumulated in lacrimal lakecapillary actionL. canaliculiL. sacnasolacrimal ductnasopharynxswallowed.Tears protect
conjunctiva w/ its enzymes
Conjunctivitis is swelling (inflammation or infection) of the conjunctiva By bacteria, irritants and viruses.
Layer: 3 but 4th
is cuplike CT layer Fascial Sheath of Eyeballsupport it w/in orbit1. Fibrous Outer Layer-sclera(attachment for extrinsic&intrinsic musc
cornea (avascular). 2. Vascular middle layer- Choroid & Iris(has muscles sphincter pupillae /dilator pupillae on surface of lens and central aperture aka
for transmitting light). 3. Inner layer- retina (neural layer is light receptive &pigmented layer is light absorbing ) &Fundus of eyeball (light focus here) &
Optic Disc aka blind spot (CN2 enter eyeball here)
Dilator Pupillae- radially arranged smooth muscle fibers. Sphincter Pupillae- circularly arranged (CN3ciliary ganglion
Macula- yellow spot of retina, has photoreceptor cones
Sphincter papillae decreases diameter and dilator papillae increases its diameter
Vasculature: ICCarotid Canal in Temporal BoneIC branches offophthalmic aoptic canal in sphenoid bonecentral retinal apierces dural sheat
optic noptic discretinasupplies optic retina except rods & cones Blockage of CRA= immediate blindness
Nerve: enter thru Superior Orbital Fissure. CN2 (sensory), stimulated by optical stimuli & exits via Optic Canalsurrounded by extensions of cranial
meninges & subarachnoid spacecontinuous w/ fascial sheath of eyeball & sclera. CN3(sensory) innervates extra-ocular muscles of orbit (levator Palp
superioris, recti, oblique). Recti from Common Tendinous Ring.
Path of Light: LightRefractive Media of EyeballRetina.(RME=corneaaqueous humorlensvitreous humor)
light cornea aqueous humor lens vitreous humor retina
Cornea bends light to greatest degree to focus an inverted image on optic fundus. Lens fine-tune focus on retina. VH holds retina in place & support len
central canal, if obstructed can leave you blind
Temporal Region (Temporal & Infra Temporal fossas)
Muscle of Mastication Proximal/Distal Attachments Innervation Action on Mandible
Masseter Zygomatic bone& arch/ramus of
mandible
Mandibular N. (CNV3)via masseteric n Elevates mandible
Lateral Pterygoid Infratemporal surface of
sphenoid/ joint capsule of TMJ
via lateral pterygoid Protracts mandible & depress chins
Innervated by Mandibular N. (Trigeminal n descends thru Foramen Ovale to enter the infratemporal fossa)
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Temporalmandibular Joint- synovial joint..gives lubrication to articular disc. Articular surfaces include: head of Mandible, Articular tubercle of Tempora
Bone, & Mandibular Fossa.
Translation when head of Mandible & Articular disc move anteriorly, inferiorly to the Articular Tubercleto open mouth wider. Abnormal TMJClickin
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Oral region (oral cavity, teeth, gingivae, tongue, palate & palanine tonsils)
Oral vestibule: slit-like space btw lips/cheeks supf. & teeth/gingivae deeply.Buccinator (main muscle of cheeks)
Lips & cheeks act as sphincter to push food fr oral vestibuleoral cavity proper.
Lips= fleshy muscular folds surrounding the mouth. Lymph drains to Submandibular &submental lymph nodes. Receive blood fr facial a. Has orbicularisVermillion Border- hairless, can appear red fr underlying capillary bed
Teeth-hard conical structures set in dental alveoli. Permanent set(16 in each jaw). Parts: crown, neck, root (f ixed in alveolus by fibrous Peridontium).
Enamel (hardest sub in body) covers Dentine over the crown & Cement over the root. Pulp Cavity has CT, blood vessels, & ntransmits n &vessels to A
Foramen via root canal.
Cavity(decay of enamel by lactic acid fr bacteria & sugar)pulp (has nerves)infection of pulp cavitypulpitisToothache
Gingivitis: Improper hygienefood in gumgingivitisperidontitis (alveolar bone)exposes sensitive cement of teeth
Innervation: CNV2 &CNV3 superior & inf alveolar nDental Plexus (supply maxillary & mandibular teeth)
Palate- arched roof of oral cavity proper & floor of nasal cavities. Hard Palate- formed by palantine process of maxillae & horizontal plates of palantine
bones.
Nose
Bony parts: Nasal, Maxillae, Frontal, Nasal Septum (Ethmoid & Vomer). 5 Cartilaginous parts: 2 lateral, 2 Alar, 1 septal Cartilage.
Nasal cavities open post into Nasopharynx thru Choanae of palantine bones. Lined w/ mucosa except Vestibule of Nosehas Conchae-curve inferomed
form a roof for meatus, SA to humidify nasal air (maintain pliability). Inferior 2/3 =respiratory area. Superior 1/3 = Olfactory area (olfactory receptor
neurons form nerve bundlescribiform plateolfactory bulb).
Paranasal sinuses: air-filled extentions of respiratory part of nasal cavity (Frontal-innervated by CNV1 & drains via Frontonasal duct, Ethmoid, Maxillary
drains via Maxillary ostium, Sphenoid)
Ear
External (Auricle & Ext. acoustic meatus) & Middle (Auditory Ossicle): collect & transfer sound to internal ear. Internal has organ for equilibrium & hea
Pharyngotympatic Tube: connects tympati cavity to the NasopharynxFnc: to equalize pressure in middle ear, allow air to enter & leave tympatic cavit
Popping eardrum= equaling pressure (e.g. yawn, swallow bc soft palate muscles open the cartilaginous part of tube).
Auditory Ossicle: not directly covered w/ periosteum1. Malleus (hammer), 2. Incus (Anvil),3. Stapes (Stirrups)..at base connects w/ Oval Window (open
on labyrinth wall oftympatic cavityVestibule of Bony Labyrinth). transforms the sound into audible waves
Tensor tympani muscle- arises fr superior pharyngotympanic tube , pulls on malleus, tensing the tympanic membrane to amplitude of sound
Vestibulocochlear organ: hearing & balance. Membraneous labyrinth (Endolymph-filled~Intracellular fluid balance) is w/in Bony Labyrinth (Perilymph
filled~ extracellular fluid auditory ). Vestibulocochlear n (CN8) runs thru Internal acoustic meatus. into Cochlear n (hearing) & vestibular n (balanc
Hollow Bony Labyrinth: a series of cavities (Cochlea, Vestibule, Semicircular Canals) surrounded by Otic Capsule (bone area).
Hollow cochlea contains Membranous cochlear Duct (site for hearing)
Hollow Vestibule contains Utricle & Saccule & Maculae (sensory epithelium)
Semicircular involves in rotation detection, open into membranous utricle
Sound Transmission: 1) SoundtympanicossicleOval windowvibration in Perilymph in scala vestibulibend hair cellscochlear n to brain
OR 2) bends hair cellacross cochlear ductdampen in scala tympaniROUND WINdowpharyngotympanic tube
Neck (larynx, thyroid & Parathyroid Glands)
Skeleton: C1-C7, Hyoid Bone, Manubrium & Clavicles
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Hyoid- attachm for ant neck muscles & keep airway open & tongue movement (Hyoglossus-connect hyoid to side of tongue) for articulation
Fascia: 1) Fatty Supf subcutaneous Tissue (has Platysma-muscle of facial expression
2) Deep Fascia( Investing, Preacheal, Prevertebral, Alar & Carotid) for compartmentalization & slipperiness for swallowing, turning head & neck
a)Investing Layer invests: Sternocleidomastoid & Trapezius muscles(@corners of neck)/ submandibular & parotid glands (superiorly)
b)Pretracheal Layer: fr hyoid into thorax..here blends w/ fibrous pericardium covering heart. Encloses infrahyoid muscles, thyroid gland, trac
& esophagus. Buccopharyngeal fascia is part of pretracheal
c)prevertebral of deep cervical fascia (cervical sympathetic ganglia )
Fixed to cranial base (sup), Longitudinal Ligament (ant), Nuchal Ligament (post). & extends into Axillary Sheath.
Levator Scapulae & Scalene muscles attach to Transverse process of Cervical vertebrae.
d)Carotid Sheath contains: tubular fascia, Common & Internal Carotid Arteries, Internal jugular veins, Vagus n (CN 10), & deep cervical lymph
nodes.
where must sympathetic ganglia be In the prevertebral layer
Retropharyngeal Space: potential space btw prevertebral & Pretracheal Layer, for movement during swallowing, major path for infection spread
Infection: Abcess (swollen area w/ pus, post to prevertebral fasciaswelling post to SCMastoid). Pus may perforate prevertebral layerretropharyng
spacebulge in pharynDysphagia(difficulty swallowing)Dysarthria (difficulty speaking)
Structures: 4 major regions- SCM(neck into ant & lat. Cervical s), Post Cervical, Lat C, Ant C
Lateral Cervical : (venous path) External jugular v.subclavian vbrachiocephalic SVC. (normal venous pressure=Ext jug v is visible briefly, EJV
prominent when venous pressure )
Subclavian v used for Central Line Placement toparenterally(outside of alimentary tract) insert nutria fluids & chemotherapy, lies ant.inf to subcla a.
has Spinal Accessory n. (CN11): supf n, but crosses deep to SCM muscle
Roots of Brachial Plexus C5-T1 (ant rami) btw scalene muscles ..Rotator Cuff
Roots of Cervical Plexus C1-C4(ant rami) deep to SCM, Phrenic n
Nerve Block: Regional Anesthesia for surgery in neck/upper limb. Cervical Plexus Block: when anesthetic agent is injected @Nerve Point of Neck.
Supraclavicular Brachial Plexus Block: when injected into supraclavicular part of brachial plexus
Venous Angle: junc of internal jugular &subclavian v(see pic)
Anterior Cervical: Left aorta does not have Brachiocephalicregion. So , aortaL subclavian & L Common Coratid (notice, not brachiocephalic)
aortaR. Brachiocephalic trunkR Subclavian & R Common Coratid
for veins: SVCR/L Brachiocephalic vR/L Subclavian R/L Interjugular
baroreceptors (IX and X) react to changes in arterial blood
chemoreceptors (IX and X) monitors level of oxygen in the blood, increase the blood pressure
Common Coratid A.carotid .
Coratid Sinus=slight dilation in Internal Coratid @bifurcation, innervated by CN9 &10. It is a baroreceptor(responds to s in arterial blood pressure), h
carotid body (a chemoreceptor) to monitor level of O2 in blood.
Viscera: 3 layers Supf to Deep- 1. Endocrine (parathyroid & thyroid glands), 2. Respiratory (Larynx & Trachea), 3. Alimentary (Pharynx & Esophagus)1.Thyroid gland makes thyroid hormones (controls metab) & Calcitonin(Ca in blood), locate anterolaterally to larynx & Trachea, consists of R &L lobe
interconnect by thin Isthmus. Nerves here fr cervical sympathetic ganglia.
Parathyroid glandis posteromedial to thyroid gland, makes parathyroid hormones (calcium in blood)
2.Larynx (produce voice). Inferior horns of thyroid cartilage articulates w/ cricoid cartilage @cricothyroid joints. Fnc: rotation & gliding of thyroid
cartilages in length of vocal folds. Epiglottic cartilage gives flexibility to epiglottis.
Larynx connects oropharynx w/ trachea, has 9 cartilages (most prominent is Thyroid Cartilage (bottom end of laryx)-the only laryngeal cartilage that fo
a complete ring around airway. AKA Adams Apple).
Interior Larynx: has Rima Glottitus (aperture btw vocal folds), Narrow &wedge shaped during ordinary breathing, Slit-like during phonation. Vestibular
Folds are false vocal cords. Vocal cords separated @rest, but close (not tightly) to produce audible vibration
Thyro-arytenoid: relaxes/ shortens vocal ligamentss pitch of voice, innervated by inf laryngeal n. (CN 10)
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Trachea- inf to larynx, ends at Manubriosternal jointR & L bronchi, laterally have common carotid a & thyroid lobes
3. Pharynx- post to larynx & Trachea, directs food to esophagus. Pharyngeal muscles in wall of pharynx: External circular & Internal Longitudinal. Tonsils
in nasopharynx. Tonsillectomy- removal of palantine tonsil. Tonsilectomy- common in children.
Zones of Trauma: 1) Manubrium to CricoidApices of lungs &Trachea
2) Cricoid to MandibleLarynx
3) Superior to MandibleOral &Nasal Cavities, Oropharynx & Nasopharynx
Zone 1 &3 have greatest mortality
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