le3 - EARS NOSE PNS

Name the 3 ARTERIAL SUPPLY OF THE EXTERNAL NOSE.

💡 ONI IFM

💡 ONI IFM

→ Ophthalmic branch of the internal carotid artery → Nasal branches of the facial artery → Infraorbital branch of the maxillary artery

VENOUS DRAINAGE OF THE EXTERNAL NOSE The venous blood drains mostly into the facial vein via the ____________________.

(A) Sphenopalatine, facial, and ophthalmic veins (B) Angular and Lateral Nasal veins

B) Angular and Lateral Nasal veins

The superficial drainage is organized into regional groups. Which group of lymph nodes drains the chin and central lower lip?

Buccal Submental Submandibular

Submental

The superficial drainage is organized into regional groups. Which group of lymph nodes drains the retroauricular area?

Anterior/superficial cervical Occipital Mastoid

Mastoid

The superficial drainage is organized into regional groups. Which group of lymph nodes drains the lateral face including the eyelids?

Occipital Mastoid Parotid

Parotid

The superficial drainage is organized into regional groups. Which group of lymph nodes drains the upper lip & lateral lower lip?

Buccal Submental Submandibular

Submandibular

NERVE SUPPLY OF THE EXTERNAL NOSE Which nerve innervates the Alae?

(A) Nasociliary branches of V1 (Ophthalmic Nerve) (B) Infraorbital nerve from V2 (Maxillary nerve)

(B) Infraorbital nerve from V2 (Maxillary nerve)

BOUNDARIES OF THE NASAL CAVITY ● Formed by: → Palatine process of maxilla → Horizontal Plates of Palatine Bone

Floor of Nasal Cavity

BOUNDARIES OF THE NASAL CAVITY ● Formed by: → Body of Sphenoid → Cribriform Plate of Ethmoid → Nasal part of the Frontal Bone → Nasal Bone → Lateral Nasal Cartilage

Roof of Nasal Cavity

BOUNDARIES OF THE NASAL CAVITY ● Anterior: Septal Cartilage ● Inferoposterior: Vomer ● Superoposterior: Perpendicular plate of Ethmoid

Medial Wall (Nasal wall)

BOUNDARIES OF THE NASAL CAVITY ● Osteocartilaginous wall ● It is also here where you will find the Kiesselbach's (Little's) Area

Medial Wall (Nasal wall)

→ Space above the nasal concha that receives the opening of the sphenoidal air sinus (or sphenoidal sinus)

Sphenoethmoidal recess

Meatus: Opening beneath each concha ▪ Receives the opening: posterior ethmoidal sinus

Superior Meatus ▪ Lies below superior concha

Meatus: Opening beneath each concha ▪ Receives the opening: anterior & middle ethmoidal sinuses and maxillary & frontal sinuses

Middle Meatus ▪ Longer & deeper than the superior meatus

Meatus: Opening beneath each concha ▪ Receives the opening: Nasolacrimal duct

Inferior Meatus

TWO TYPES OF MUCOUS MEMBRANE ● Made up of Pseudostratified Ciliated Columnar Epithelium Without Goblet cells ● Lines the superior ⅓ of the nasal cavity

OLFACTORY MUCOUS MEMBRANE

OLFACTORY MUCOUS MEMBRANE ▪ Located in between basal cells and olfactory cells ▪ Base is narrower compared to apical surface ▪ Apical surface is broad and has microvilli

Supporting (Sustentacular) Cells

OLFACTORY MUCOUS MEMBRANE ▪ Small, spherical shaped cells ▪ Considered as a stem cell because of its capability of differentiating into supporting and olfactory cells ▪ Capable of regeneration

Basal Cells

OLFACTORY MUCOUS MEMBRANE ▪ Apical surface has knob-like structure that contains abundant non-motile stereocilia ▪ Considered as bipolar neuron (has dendrite and axon)

Olfactory (Sensory) Cells

OLFACTORY MUCOUS MEMBRANE ▪ Beneath olfactory epithelium ▪ Purely serous ▪ Provide constant flow of serous fluid that cleanses the cilia of debris to facilitate access to new odoriferous substances

Bowman's Glands

● Function: To warm, moisten & clean inspired air ● Made up of Pseudostratified Ciliated Columnar Epithelium With Goblet Cells ● Lines the inferior ⅔ of the nasal cavity except vestibule (lined by the skin)

RESPIRATORY MUCOUS MEMBRANE

ARTERIAL SUPPLY OF NASAL CAVITY ● Posterior ethmoidal branch ● Anterior ethmoidal branch

What is the artery of origin of these branches?

💡 O - PA

Ophthalmic artery (from the ICA)

ARTERIAL SUPPLY OF NASAL CAVITY ● Sphenopalatine artery ● Greater palatine artery

What is the artery of origin of these branches? 💡 M - SG

Maxillary artery

ARTERIAL SUPPLY OF NASAL CAVITY ● Septal branch of superior labial artery

What is the artery of origin of this branch? 💡 FS (FanSign)

Facial artery

→ Formed by the anastomoses of the facial, ophthalmic and maxillary arteries → Located in the anteroinferior part of nasal septum → This area is prone to bleeding (epistaxis)

Kiesselbach's (Little's) Area

VENOUS DRAINAGE OF NASAL CAVITY There is a rich plexus in submucosa eventually draining into the __________________________.

💡 Artery Supply of nasal cavity: FOM 💡 Venous Drainage of nasal cavity: FOS

💡 FOS Facial, Ophthalmic and Sphenopalatine veins

Lymph from the vestibule is emptied into the ____________________________.

💡 In external nose, this lymph node drains into upper and lateral lower lips.

submandibular nodes

Lymph other portions of nasal cavity is emptied into the upper _____________________________ that run along the entire length of the internal jugular vein.

deep cervical nodes

Draw an imaginary line from the sphenoethmoidal recess all the way to the apex of the nose. Area above the imaginary line is innervated by branches from _______________________.

(A) Ophthalmic nerve (V1) (B) Maxillary nerve (V2)

(A) Ophthalmic nerve (V1)

Draw an imaginary line from the sphenoethmoidal recess all the way to the apex of the nose. Area below the imaginary line is innervated by branches from ____________________.

A) Ophthalmic nerve (V1) (B) Maxillary nerve (V2)

(B) Maxillary nerve (V2)

External nose is innervated mainly by the ophthalmic nerve except Ala, which is supplied by _________________________.

maxillary nerve

● Largest, pyramidal sinus ● Most frequently infected sinus in the human body because drainage is suboptimal

MAXILLARY SINUS

PARANASAL SINUSES ● Drains into middle meatus via the hiatus semilunaris

MAXILLARY SINUS

ARTERIAL SUPPLY OF MAXILLARY SINUS? 💡 S-max arteries

Superior alveolar branch of maxillary artery

The arterial and nervous supply of maxillary sinus came from maxillary artery. They just differ in terms of alveolar branches.

NERVE SUPPLY OF MAXILLARY SINUS? 💡 AMP-max nerve

Anterior, middle and posterior (AMP) alveolar branches of Maxillary nerve (V2)

PARANASAL SINUSES ● Detectable at age 7 ● Triangular in shape ● Opens into middle meatus through the infundibulum via the nasofrontal duct

FRONTAL SINUS

PARANASAL SINUSES ● Cuboidal in shape ● Derived from the posterior cells that invades the area at age 2

SPHENOIDAL SINUS

Which among the paranasal sinuses has the following arterial and nerve supply?

● Blood Supply: Posterior ethmoidal branch of ophthalmic artery ● Nerve Supply: Posterior ethmoidal branch of nasociliary nerve (V1)

SPHENOIDAL SINUS

PARANASAL SINUSES ● Recognizable in CT scan before age 2 but not in radiograph ● Found in between nose and orbit

ETHMOIDAL SINUS

Which among the paranasal sinuses has the following arterial and nerve supply?

● Blood Supply: Anterior and posterior ethmoidal arteries ● Nerve Supply: Anterior and posterior ethmoidal nerves (nasociliary branch of V1)

💡 Very same to each other!!!

ETHMOIDAL SINUS

● Remember that the posterior ethmoidal sinus lies very close to the optic canal and this allows passage of the optic nerve and the ophthalmic artery!

ARTERIAL SUPPLY OF THE EARS?

💡 Arterial Supply: PA-ST arteries 💡 Venous Drainage: PA-ST veins

→ Posterior auricular artery → Superficial temporal artery

BOTH are branches of ECA!

This branch from the Vagus nerve explains why a person coughs involuntarily when he cleans his ears.

Auricular branch from Vagus/Facial nerve

The external auditory canal has 2 portions: Cartilaginous and Osseous. Which one is being described below: ▪ Auditory process and outer 1/3 ▪ Covered with thin skin w/ hair, sebaceous & ceruminous glands

Cartilaginous Portion

The external auditory canal has 2 portions: Cartilaginous and Osseous. Which one is being described below: ▪ Formed by tympanic plate of the temporal bone ▪ Absent Ceruminous glands (modified sweat glands, apocrine, simple coiled tubular which secrete the cerumen/earwax)

Osseous Portion: inner ⅔

NEUROVASCULATURE OF THE EAC → Main sensory nerve supply, outer surface of tympanic membrane

Auriculotemporal branch of mandibular nerve

💡 Also one of the general sensory nerve supply of the pinna (auricle)

NEUROVASCULATURE OF THE EAC → inner surface of tympanic membrane

Glossopharyngeal nerve

Cone of light projects from the umbo, located at the _________________ quadrant of the tympanic membrane.

anteroinferior

TRUE OR FALSE. External Auditory Canal and Tympanic Membrane have the same sensory nerve supply.

TRUE!

→ Auriculotemporal branch of mandibular nerve → Auricular branch of the vagus nerve → Glossopharyngeal nerve

Clinical Correlation: Acute Otitis Media (Infection of the Middle Ear) ● Safest part to cut is the ______________ quadrant.

posteroinferior

Clinical Correlation: Acute Otitis Media (Infection of the Middle Ear) You don't incise at the ______________ quadrant as you might affect the ossicles and chorda tympani.

posterosuperior

BOUNDARIES OF MIDDLE EAR ▪ Separates the middle ear cavity from the dura mater that covers the temporal lobe of the cerebral hemisphere that lies in the middle cranial fossa ▪ Formed by a thin plate of bone of the petrous portion of the temporal bone

Tegmental Wall (Roof) ▪ Formed by a thin plate of bone of the petrous portion of the temporal bone called the tegmen tympani

BOUNDARIES OF MIDDLE EAR ▪ Separates the middle ear cavity from the superior bulb of the internal jugular vein ▪ Formed by a thin plate of bone called the fundus tympani

Jugular Wall (Floor

BOUNDARIES OF MIDDLE EAR ▪ Formed by the promontory which is the initial part or basal turn of the cochlea ▪ On the left side of the promontory are 2 openings: Fenestra vestibuli/ oval window and − Fenestra cochlea/ round window

Labyrinthine Wall (Medial Wall)

BOUNDARIES OF MIDDLE EAR ▪ Formed by the tympanic membrane and squamous part of the temporal bone

Membranous Wall (Lateral Wall)

BOUNDARIES OF MIDDLE EAR o Represents the communication between middle ear cavity and the nasopharynx o Open when a person yawns and closes when a person chews o Function: equalizes the pressure of the middle ear cavity with respect to the atmosphere

Pharyngotympanic Tube

BOUNDARIES OF MIDDLE EAR − Auditory Tube/ Eustachian Tube/ Pharyngotympanic Tube − Canal for the tensor tympani muscle

Carotid Wall (Anterior Wall)

BOUNDARIES OF MIDDLE EAR ▪ Open and consists of Aditus ad antrum, Canal for facial nerve, Pyramidal eminence, Fossa incudis and Prominences produced by facial nerve canal and lateral semicircular canal.

Mastoid Wall (Posterior Wall)

Any infection from the nasal cavity or pharynx can spread into the tympanic cavity via what structure in the anterior wall of middle ear cavity?

pharyngotympanic tube

Muscles of Middle Ear ▪ Inserts to the handle of the malleus ▪ When it contracts, it tenses the tympanic membrane thereby protecting the inner ear when exposed to loud sounds

Tensor tympani

Muscles of Middle Ear ▪ Small muscle ▪ Innervation: Mandibular branch of the Trigeminal nerve

Tensor tympani

Muscles of Middle Ear ▪ Smallest muscle in the body ▪ Arises from the pyramid and inserts into the neck of the stapes

Stapedius

Muscles of Middle Ear ▪ When contracted it prevents excessive vibration of the stapes protecting the middle ear from loud sounds ▪ Innervation: Facial nerve

Stapedius

Hyperacusis or hyperacusia is the excessive acuteness of hearing secondary to paralysis of the stapedius muscle, resulting from the uninhibited movement of the stapes (stirrup). What nerve could be damaged?

Facial nerve

Branch of the facial nerve that enters the middle ear cavity from its posterior wall insinuating itself between the incus and malleus. It provides taste sensation to the anterior 2/3 of the tongue.

Chorda tympani nerve

→ Found on the surface of the promontory → Made up of the tympanic branch (Jacobson's nerve) coming from the glossopharyngeal nerve (CN IX) and sympathetic nerve coming from the carotid plexus, sensory innervation to the mucosa of the middle ear, mastoid cells, and auditory tube

Tympanic plexus of nerves

NERVE SUPPLY OF MIDDLE EAR comes from _______________ which is located on the surface of the promontory and made up of the tympanic branch of the glossopharyngeal nerve or Jacobson's nerve and sympathetic fibers from the carotid plexus.

Tympanic plexus

Part of cochlea that delivers forward pressure from the vestibule (for sensory of hearing)

(A) Scala Vestibuli (B) Scala Tympani

(A) Scala Vestibuli

Part of cochlea that delivers backward pressure from the helicotrema (for sensory of hearing)

(A) Scala Vestibuli (B) Scala Tympani

(B) Scala Tympani

VESTIBULAR LABYRINTH → Irregularly oblong and bigger than saccule → Contains the vestibular receptor macula utriculi, a kind of sensory epithelium that detects horizontal acceleration and is located at the floor of the utricle (like inside the car)

Utricle

VESTIBULAR LABYRINTH → Small and spherical in shape → Contains the vestibular receptor macula sacculi, a kind of sensory epithelium that detects vertical acceleration and is located at the medial wall of the saccule (like inside the elevator!)

Saccule

Maculae are what kind of receptors?

Maculae are both static and dynamic receptors.

▪ Static: they detect the tilt of the head in space ▪ Dynamic: they detect linear or translational motion such as straight line movements (back-and-forth and up-and-down)

▪ Detects angular motion of head in space ▪ The structure is similar to that of the maculae ▪ The hair cells project into the dome-shaped gelatinous mass called the cupula

Crista ampullares

In the upper part of the spiral ligament are numerous capillaries in close association with stratified epithelial cells called ______________ that produces the endolymph found within the cochlear duct or scala media.

Stria vascularis

The organ of Corti is made up of Inner hair cells and Outer hair cells. Which one is composed of a single row TRUE auditory receptor cells responsible for converting sound stimuli into nervous impulses by the process of transduction?

Inner hair cells

The organ of Corti is made up of Inner hair cells and Outer hair cells. Which one is composed of three rows and act as an amplifier allowing the organ of Corti to be more selective and more attuned to certain sound frequencies?

Outer hair cells

HISTOLOGY OF THE COCHLEA → Central pillar → Contains the cochlear nerve and spiral ganglion (contains bipolar sensory neurons whose axons form the cochlear nerve)

Modiolus

HISTOLOGY OF THE COCHLEA → Apex → Contains helicotrema which is an opening by which the scala vestibuli communicates with scala tympani

Cupula

What does macula have that crista ampullaris don't have?

Calcium carbonate crystals or otoliths or otoconia

Moreover, cupula is not gravity sensitive and stimulation of cristae is through movement of endolymph within semicircular ducts

Name the BLOOD SUPPLY of the inner ear.

💡 In A Style

→ Internal auditory artery → Stylomastoid artery

Name the VENOUS DRAINAGE of the inner ear.

Internal auditory vein

TRUE OR FALSE: External Nose is composed of Elastic Cartilage.

False.

External Nose is composed of HYALINE Cartilage.

What is the roof of the cochlear duct or scala media? a. Spiral lamina b. Organ of Corti c. Reissner's membrane

c. Reissner's membrane

AKA Vestibular membrane

Both the anterior and posterior ethmoidal branches come from the ophthalmic artery

a. True b. False

a. True

💡 O - PA Ophthalmic artery - Posterior and Anterior ethmoidal branches

What is the medial wall of the middle ear?

a. Carotid wall b. Labyrinthine wall c. Membranous wall d. Mastoid wall

b. Labyrinthine wall

______ is the portion of the external auditory canal that is covered with ceruminous glands.

a. Osseous portion b. Cartilaginous portion c. Osteocartilaginous portion

b. Cartilaginous portion

TRUE OR FALSE The cochlea and semicircular canals are located anterior and posterior to the vestibule respectively.

TRUE

TRUE OR FALSE The framework of the pinna is made up of hyaline cartilage.

FALSE Elastic cartilage, not hyaline

TRUE OR FALSE The cone of light is reflected at the posteroinferior quadrant of the tympanic membrane

FALSE Anteroinferior quadrant

TRUE OR FALSE The internal surface of the tympanic membrane is innervated by CN IX

TRUE glossopharyngeal nerve (CN IX)

TRUE OR FALSE The pyramidal eminence forms part of the medial wall of the tympanic cavity

FALSE pyramidal eminence is at the posterior wall (Mastoid Wall)

TRUE OR FALSE The footplate of the stapes is attached to the round window by the annular ligament

FALSE should be oval window, not round

TRUE OR FALSE The membranous labyrinth found in the vestibule consists of the utricle and saccule

TRUE

TRUE OR FALSE The basilar membrane partly separates the cochlear duct from the scala tympani

TRUE

TRUE OR FALSE The spiral ligament produces the endolymph in the membranous labyrinth

FALSE stria vascularis produces endolymph

TRUE OR FALSE The vestibular receptors found in the ampullae of the semicircular ducts are the maculae

FALSE maculae is found in the utricle and saccule while the cristae ampullaris is found in the ampullae of SCC

TRUE OR FALSE The nasal cavity opens into the nasopharynx via the choanae.

TRUE

TRUE OR FALSE The turbinates are scroll-like structures on the medial nasal wall.

FALSE turbinates/concha are found in the lateral wall of the nasal cavity, kiesselbach is the one found on the medial wall

TRUE OR FALSE The nasal septum is lined by pseudostratified ciliated columnar epithelium with goblet cells.

FALSE without goblet cells

TRUE OR FALSE The sphenoidal air sinus drains into the superior meatus.

FALSE sphenoidal air sinus drains into the sphenoethmoidal recess)

TRUE OR FALSE Bleeding from the nose comes most likely from rupture of the blood vessels in the septal wall.

TRUE