HEENT (2).pdf

Bones of the Skull (cranium) ↙ ↘ Neurocranum (8) Viscerocranium (14) ↓ ↓ Frontal Nasal (2) Parietal (2) Lacrimal (2) Temporal (2) Palatine Bone Occipital Inferior Nasal (concha) (2) Sphenoid Maxilla (2) Ethmoid Zygomatic (2) Vomer Mandible 5 special senses: 1. Smell (olfaction) →...

Bones of the Skull (cranium) ↙ ↘ Neurocranum (8) Viscerocranium (14) ↓ ↓ Frontal Nasal (2) Parietal (2) Lacrimal (2) Temporal (2) Palatine Bone Occipital Inferior Nasal (concha) (2) Sphenoid Maxilla (2) Ethmoid Zygomatic (2) Vomer Mandible 5 special senses: 1. Smell (olfaction) → olfactory receptors 2. Taste (gustation) → gustatory receptors 3. Vision → photoreceptors 4. Hearing → hair cells of the cochlea 5. Equilibrium → hair cells of the ampulla & macuale IMPORTANT OPENINGS OF THE SPHENOID 1. Sphenoid Bone → bat shaped a. Optic foramen: i. CNII (vision) b. Superior orbital fissure: slit between greater & lesser wings i. CN III, IV, VI c. Foramen rontundum: lateral to sella turcica i. CNV d. Foramen ovale: Posterior to sella turcica i. e. CNV Foramen Spinosum i. Middle meningeal artery MAJOR PARTS OF THE ETHMOID BONE 2. Ethmoid Bone → between nasal & orbital cavity a. Cribriform plates = roof of nasal cavities i. olfactory foramina (transmits fibers of CNI) b. Ethmoidal labyrinth = ethmoidal air cells i. superior & middle nasal conchae c. Perpendicular plate = Forms superior part of nasal septum i. Lots of sinuses Viscerocranium (Facial bones) 1. Lacrimal (2) 3. Inferior Nasal (concha) Bone 2. Palatine Bone AREAS OF THE MAXILLA BONES 4. Maxilla Bone (2) a. Palatine processes → anterior part of the hard palate b. Frontal processes → Lateral bridge of nose connects frontal & nasal bones c. Zygomatic processes → Connects w/ zygomatic bones d. Inferior orbital Fissure → Opening w/in each orbit i. formed by maxillae & sphenoid e. Infraorbital foramen → Opening under each i. f. passage of infraorbital nerves & vessels Alveolar margin →Oral margin of maxillae that contains the upper teeth THE NOSE 1. Includes external nose & nasal cavity 2. Functions of the nose: a. Smell, humidification, Respiration & Filtration b. Reception & eliminate secretions → paranasal sinuses & nasolacrimal ducts EXTERNAL NOSE: 1. Inferiorly → cartilage & skin 2. Superiorly = Dorsum → 4 parts a. Nasal spine & bones, frontal process(maxillae), & nasal part(frontal bone) 3. Nerve supply from CNV1 (Trigeminal Nerve, Ophthalmic Branch) Nasal Cavities 1. Right & Left (nares = nostrils) → divided by nasal septum 2. lined w/ mucous membrane 3. 3 projecting conchae (turbinates) a. ↑ SA for cleansing, humidification & temperature control of inspired air 4. Vascular supply = form the Kiesselbach plexus (triangle) = nosebleeds Nasal Septum 1. Divides nasal chamber → 2 nasal cavities 2. Bony and cartilaginous parts 3. Main parts: a. Perpendicular plate of the ethmoid bone = superior nasal septum b. Vomer bone (P&A of nasal septum) & septal cartilage Paranasal Sinuses = allows head to not flop over 1. 4 paired air-filled extensions → respiratory part of nasal cavity a. Ethmoid & sphenoid - can only see on CT scan b. Frontal & Maxillary → palpable during the physical exam 2. Lighten the weight of the skull Olfaction (smell): 1. Olfactory Epithelium - mucous membrane on roof of nasal cavity 2. Olfactory Nerve(s) → CNI a. Exit through the cribriform plate of the ethmoid bone b. Pick up molecules of smell then go to bulbs 3. Olfactory bulbs 4. Olfactory tract: the final portion of sense of smell → cerebrum THE EAR 1. Hearing & equilibrium/balance system 2. 3 general parts → External, Middle, and inner EXTERNAL EAR 1. Auricle (pinna), EAM (auditory canal), & TM (externally) AURICLES 1. Helix, Tragus, Lobule EXTERNAL ACOUSTIC MEATUS (AUDITORY CANAL) 1. External ⅓ formed by cartilage; inner ⅔ by bone (temporal bone) 2. Direct sound waves to the TM MIDDLE EAR → Amplifies sound 1. Tympanic Membrane (internally = eardrum) - collagen & epithelium fibers 2. Auditory Ossicles - vibrate sound and get it to our brain a. Malleus & Incus - can see on exam b. Stapes - smallest & most medial - gets sound to next part of ear 3. Pharyngotypanic (Eustachian) tube - pressure & connections ears to throat TYMPANIC MEMBRANE (TM) 1. Pars Flaccida - small ▵ portion of TM; lacks fibrous layer 2. Pars Tensa - remainder of TM 3. “Cone of Light”(landmark) - ▵ reflection of light → anterior inferior of the TM a. Missing= rupture or infection 4. Ubmo - most depressed center part of the TM ; end of Malleus INNER EAR 1. Bony Labyrinth → Cochlea & semicircular canals (SCC) 2. Membranous labyrinth → Cochlear duct & 3 SCC connected by saccule & utricle 3. 2 functions → acoustic apparatus & vestibular apparatus EQUILIBRIUM 1. Vestibule: detects the movement → forces of gravity (static equilibrium) a. Saccule & Utricle 2. Semicircular canals: detects angular movements of head (dynamic equilibrium) a. Semicircular ducts and ampullae NERVE SUPPLY TO THE EAR 1. Auricle & external auditory meatus → Mostly CNV, Minor CN VII & X 2. TM a. External → CNV & small ear CN X & Internal → CNIX 3. Middle Ear → Mix of CNV3 & VII 4. Internal Ear → CNVIII → sense of hearing & balance ( vestibular nerve & acoustic nerve) LIPS & MOUTH 1. Open to oral cavity & controlled by series of muscles 2. Edge of lips → vermillion border Oral Cavity - starts by definition behind your teeth 1. Lined w/ mucous membrane 2. Openings for salivary gland ducts a. Partoid → buccal surface of upper cheek opposite the 2nd maxillary molar i. Stensen’s Duct Orifice b. Submandibular → each side of the lingual frenulum @ the base of tongue i. Wharton’s Duct Orifice c. Sublingual → # of openings in floor of the mouth along sublingual folds 3. Teeth: Innervated → Trigeminal nerve (CN V) 4. Maxillary Gingiva → MM & fibrous tissue hold upper teeth → buccal & lingual 5. Mandibular Gingiva → MM & fibrous tissue hold lower teeth 6. Bones of oral cavity a. Mandible → lower jaw; hinge joint at TMJ b. Maxilla (palatine process) → anterior ⅔ of hard palate c. Palatine (Horizontal plate) → posterior ⅓ of hard palate TONGUE → a muscle 1. Functions → forms words, swallowing, taste, and oral cleansing 2. 4 intrinsic muscles → confined w/in tongue, not attached to bone a. Genioglossus → bilateral depresses tongue b. Hypoglossus → depresses tongue c. Styloglossus → retrudes & curls tongue d. palatoglossus → depress soft palate 3. 4 extrinsic muscles → outside tongue & attach to it a. Superior longitudinal → curls tongue; elevating apex b. Inferior longitudinal → curls tongue; depressing apex c. Transverse → narrow & elongate tongue d. vertical → flattens & broadens tongue 4. Muscles of movement: All are innervated → CN XII a. EXCEPT palatoglossus muscle → CNX 5. Anterior ⅔ tongue sensory innervation: CNV → touch & pain & CNVII → taste 6. Posterior ⅓ sensory: CNIX & small area for CN X LINGUAL PAPILLAE 1. Vallate papillae → bitter taste a. Largest of the papillae 2. Foliate papillae → sense of bitter, sour, and salty taste 3. Fungiform papillae → sweet taste 4. Filiform → no taste bunds but responsible for pain TONSILS 1. Lymphoid tissue → Trap bacteria & viruses and produces antibodies 2. Palatine → “tonsils” 3. Innervated → branches of CN V & IX 4. Lingual → located on the posterior oral surface of the tongue 5. Adenoid → are found @ the posterior of the nasal cavity (less visible as adult) PHARYNX “THE THROAT” = Passageway for both air & food 1. Extends past the larynx 2. Separated into 3 sections: Nasopharynx, Oropharynx, Laryngopharynx EPIGLOTTIS = Part of the larynx 1. Elastic cartilage 2. Function: Protect larynx from food & Allows food to go down esophagus HYOID BONE= @ level of the 3rd cervical vertebrae 1. Only bone to NOT articulate w/ another bone in the body 2. Provides support for the larynx & airway 3. Muscles of deglutition (swallowing) attach to it for swallowing LARYNX 1. Found in the anterior neck @ level of C3-C6 2. Contains the vocal cords 3. Connects oropharynx w/ trachea 4. Function → guard air passages, especially during swallowing LARYNX STRUCTURE 1. Thyroid → (adamapples) 2. Cricoid (palpable) → below thyroid 3. Epiglottic , Arytenoid x2 , Corniculate x2, Cuneiform x2 - cant feel on PE SWALLOWING (DEGLUTITION) 1. Process: food → oral cavity → esophagus → stomach 2. Involves the teeth, tongue, larynx/pharynx & esophagus 3. 3 phages - oral, pharyngeal, esophageal a. Oral (not autonomic) contraction of tongue → food bolus up against soft palate → posteriorly oropharynx b. Pharyngeal phase (autonomic): elevation of larynx → epiglottis blocks the trachea → bolus to esophagus c. Esophageal (autonomic): food bolus→ esophagus→stomach via peristalsis Temporomandibular Joint= Most active join in the human body MUSCLE OF MASTICATION ***need to know*** 1. Masseter, temporalis, medial pterygoid → elevate mandible & closing mouth 2. Lateral pterygoid → depress mandible to open the mouth 3. All are innervated by CNV MUSCLE OF THE NECK 1. Necessary for movement, chewing, swallowing, & facial expression 2. Flexion muscles: Sternocleidomastoid ,scalene, & longissimus capitis 3. Extension muscles: splenius capitis & cervicis PLATYSMA → more superficial than sternocleidomastoid 1. Innervvated → CNVIII 2. Functions → tense the skin of the neck 3. Muscle of facial expression → platysma serves to convey tension or stress THE EYE COMPONENTS 1. Orbit, Globe, Extra ocular muscles (EOM), eyelids, tear glands & ducts THE ORBIT 1. Boney socket that protects the eyeball from injury 2. Composed of 7 bones a. Frontal , Zygomatic , Maxilla, Nasal b. Sphenoid, Ethmoid, Lacrimal 3. openings for nerves & blood vessels to the globe, orbit, & eyelids THE GLOBE 1. Composed of 3 layers (tunics) w/ fluid & gel-like substances a. Outer layer (fibrous) - clear & cornea b. Middle layer (vascular) - choroid c. Inner layer (neural) - retina 2. 3 chambers a. Anterior & Posterior - replenished b. Vitreous - gel like not replenished OUTER LAYERS (FIBROUS) 1. Sclera: white of the eye 2. Cornea: transparent convex covering anterior part of eye - bend of light 3. Conjunctiva: not a part of eyeball → covers sclera & lines lids - provides nutrition MIDDLE LAYER (VASCULAR) 1. Choroid: layer that contains a rich network of blood & lymphatic vessels a. Red-flex to eye → helps absorb light 2. Ciliary body: anterior thickening portion of choroid composed of smooth muscle a. Sits behind iris & supports the lens & iris b. Ciliary body & lens divide anterior cavity into anterior & posterior chambers 3. Pupil: black area in the middle of the iris that allows for light transmission into the eye 4. Iris (pigmented): contains 2 involuntary muscles that control the size of the pupil a. Sphincter pupillae (constricts the pupil/ makes it smaller) b. Dilator pupillae (dilates the pupil/makes it bigger) INNER LAYER (NEURAL) 1. Retina: a. Photoreceptors & associated w/ neurons & fibers b. Fundus: area of light focus on retina i. Rods & cones for vision sense 1. Rods = B&W vision 2. Cones = color vision c. Macula Lutea = yellow spot → clearest vision i. contains only photoreceptors 1. Fovea centralis = vision is most accurate d. Optic disk i. Entry point for sensory nerves & blood vessels ii. Blind spont of the inner eye e. Optic nerve (CN II) i. Passes from back of globe via optic canal in the sphenoid bone 3 CHAMBERS OF THE EYE 1. Anterior chamber → Cornea & the iris 2. Posterior chamber → Iris & the lens 3. Vitreous chamber → Lens & the retina ANTERIOR, POSTERIOR CHAMBER& AQUEOUS HUMOR 1. Ciliary processes of the ciliary body a. Aqueous humor = nourishes the iris, lens, & cornea 2. Circulates from posterior chamber of pupil → anterior chamber 3. Trabecular meshwork (canal of schlemm) = angle @ the edge of the cornea & iris a. Drains aqueous humor into scleral venous sinus 4. Aqueous production = drainage → Intraocular pressure (IOP) = stable VITEROUS CHAMBER & VITREOUS HUMOR 1. Vitreous humor a. Vitreous body → Between the retina & the lens 2. Jelly like 3. Transmits light 4. Holds retina in place, supports the lens, & helps maintain eye shape EYE MOVEMENT 1. Movement of the globe→ contract of 1+ EOM depending on direction of gaze 2. 6 EOMs are: a. Superior, Inferior, Medial, lateral rectus b. Superior & Inferior oblique EYE MOVEMENT INNERVATION = LR6SO4AO3 1. CNVI (abducens): lateral rectus 2. CNIV (trochlear): superior oblique 3. CNIII (oculomotor): all other muscle NERVE OF THE EYE 1. Ophthalmic (branch of CN-V) 2. Optic (CN II) - sense of vision; joins contralateral optic nerve @ optic chiasm then occipital lobe via optic tract 3. CNs III (oculomotor),IV (trochlear),VI (abducens): supply EOMs for motion of globe BLOOD VESSELS OF THE EYE 1. Ophthalmic artery → Branch of internal carotid artery a. Enters orbit via optic canal b. 11 branches → Most important is central retinal artery → supplies retina c. End artery → does NOT anastomose w/ other arteries & only supplies the internal aspect of retina i. Occlusion results in blindness VEINS OF THE EYE 1. Drainage occurs → superior & inferior ophthalmic veins 2. Scleral venous sinus → vascular structure encircling anterior chamber of eye LACRIMAL APPARATUS 1. Lacrimal gland → upper lateral orbit on the lateral rectus & levator palpebrae superioris muscles 2. Lacrimal Sac→ Upper dilated end of the nasolacrimal duct 3. Nasolacrimal duct → Opens into the inferior nasal meatus of the nasal cavity 4. Tear movement = Lacrimal gland → gravity/ blinking → lacrimal duct → lacrimal sac → nasolacrimal duct EYELIDS 1. protects it from injury & excessive light 2. Keep cornea moist by spreading lacrimal fluid when blinking 3. Interior = palpebral conjuctiva 4. Upper & lower lids (dense band of CT) → provide support for the tissue 5. Tarsal glands: Produce lipid secretion to keep eyelids from sticking 6. Eyelashes → sensing approaching dangers & lubricated by ciliary glands 7. Orbicularis Oculi a. Closes eyelids & wrinkles forehead b. Palpebral part “gently” closes lids c. Orbital part “tightly” closes lids 8. Levator Palpebrae superiors → Elevates upper eyelid (innervated by CN III) VISION 1. Refraction of light & accommodation a. Bending of light rays & alter eye to focus on different objects via changing shape & length of lens 2. Close-up vision → Lens becomes more convex (short & thick) 3. Distant → Lens becomes less convex (long & thin) 4. Convergence → maintain binocular vision & track objects moving towards eyes