2nd Head&Neck

8/2/2019 2nd Head&Neck

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Lec (11) The Brain I

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Page 2 :

slide 1 :cerebrum consist of two cerebral hemispheres connected by mass ofwhite matter called corpus callosum

- the tentorium cerebelli: is Reflection of meninges layer of dura matter &

located over cerebellum .

slide 2: what do gray & white matters refer to ? to content of the nervescells >>the cell body &dendrite (un mylinated )are located in gray matter & the

axons which is mylinated sheet are located in white matter .

Page 3 :

slide 2 : central sulcus separates frontal lobe from parietal lobe- precentral gyrus in frontal lobe

- postcentral gyrus in parietal lobe

slide 3:nerve cross to other side within the medulla oblongata as they descendin spinal cord .

Page 4:

slide 1:site of cross over medulla oblongata .

slide 2 : central sulcus parietal from frontal lobes .

Lateral sulcus temporal from frontal & parietal lobes .

Calcarine sulcus communicates with cerebellum inferiorly .

Slide 4 : motor area in precentral gyrus

Sensory area in postcentral gyrus

Auditory area in middle of superior temporal gyrus in temporal lobe.

page 5 :

slide1 : Brocas area : location lies just above the lateral sulcus .

slide4 :what are the brain nuclei ? I don't know & I didn't find it in the textbook .

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Page 6 :

slide 2 : hypothalamus form the lower part of the lateral wall & floor of the 3rd

ventricle .

-ADH stored in post .pituitary gland

- Hypothalamus links 2 systems :

- 1 _ Nervus system

- 2 _ Hormonal system

Lec (12) The Brain II

Page 1 :

slide 2: brain stem :midbrain , pons ,medulla oblongata .

slide 3 : also contain ascending & descending fibers connecting the forebrain ,midbrain ,spinal cord .

slide 4 : medulla oblongata : connect pons above & spinal cord below .

Page 2 :

slide 1 : a taxia : cant control the movment of the muscles tone or lack ofmuscles coordination .

slide 3 : the ventricles of brain are lined with choroid plexus .which is secretionof CSF

-the choroids plexuses are made of 3 layer :

- blood capillary & ependemal cell & pia mater filitrate of blood to the

ventricles >>CSF .

slide 4 : lateral ventricles communicates with 3rd ventricle through theintrventricular foramina .

_ separated from each other by septum pellucidum .

Page 3 :

slide2 : boundaries : lateral walls thalamus

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_ communicates with 4th ventricle by the cerebral aqueduct .

slide 3: why?? To drain the CSF to the suparachnoid space .&it located in thedorsum wall ( 1 median & 2 lateral ).

Page 4:

slide 3 : 5 branches of ICA :

1- Ophthalmic artery : it pass through optic canal & it gives off the central

artery of the RETINA .

2- Ant .cerebral artery : it passes forward between the cerebral hemisphers

&then wind around the corpus callosum of the brain to supply the medial

& the superolateral surface of the cerebral hemisphere .

3- Middle cerebral artery : and also supply all the motor area of the cerebralcortex except the leg area .

4- Posterior communicating artery : run backward to join the pos. cerebral

artery which supply the occipital pole & inferolateral surface of the

hemisphere .

5- Choroidal artery : supply choroid plexus .

Page 5 :

slide 1 : posterior meningeal a. : goes to meningeal layer

-anterior spinal a.: arise from vertebral arteries , unite to form a single

artery ,which runs down within the anterior median fissure & supply spinal cord .

-posterior spinal a. :arise from vertebral a. run down the side of spinal cord &

supply spinal cord.

-posterior inferior cerebeller a. : supply cerebellum .

-medullary a. : supply medulla oblongata .

slide 2 : lapyrinthine a. :goes to middle ear to enternal aquestic meatus .

-pontine : supply the pons .

- post. Cerebral a. : supply the midbrain and visual cortex & the lateral

surface of occipital lobe .

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slide 3 : Circle Of Willis : lies in the subarachnoid space at the base of the

brain .

Lec (13) Cranial Nerves

Page 5 :

slide 1 : motor to : muscles of mastication & mylohoid , anterior belly ofdigastric , tensor veli palatine , & tensor tympani .

slide 3 : 3 main division :

- Frontal : 1 supraorbital nerve , 2- supratrochlear

- Lacrimal nerve .

- Nasocilliary nerve : 1- int. nasal nerve , 2- ext. nasal nerve .

Page 6 :

Slide 2 : main branches of the Maxillary Nerve :

1- Zygomatic branch : which divide into the zygomaticotemporal &

zygomaticofacial nerves that supply the skin of the face .

2- Ganglionic branches : which are 2 nerve suspended the pterygopalatine

ganglion in the pterygopalatine fossa , they have sensory fibers form the

nose ,palate ,& the pharynx ,lacrimal .

3- Post. Sup. Alveolar nerve : which supply the maxillary sinus as well as

the upper molar teeth & part of the gum & cheek .

4- Mid. Sup. Alveolar nerve : supply maxillary sinus & upper premolar

teeth & gum &the cheek .

5- Ant. Sup. Alveolar nerve : which supply the maxillary sinus as well as

the upper canine & the incisor teeth .

6- Meningeal branches .

Page 7 :

Slide 4: anterior division of the mandibular nerve (V3) :

1- Masseteric nerve :suppy masseter muscle .

2- Deep temporal nerves : supply the temporal muscle .

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3- Nerve to lateral pterygoid muscle .

4- Buccal nerve :supply the skin &the mucous membrane of the cheek ,

the buccal nerve only sensory branch of the ant. Division of

mandibular n. ,&the buccal n. does not supply the buccinator

muscle( which is supplies by the faical nerve) .

Slide 4: posterior division of the mandibular nerve (V3):

1- Lingual nerve(S) :supply the mucous membrane of the anterior 2/3 of

tonque &the floor of the mouth ,&it gives preganglionic parasympathetic

secretomotor fiber to the sub mandibular ganglion .

2- Auriculotemporal nerve (S): supply the skin of the auricle & the external

auditory meatus & the temporomandibular joint &the scalp &gives

parasympathetic secretomotor fiber to the parotid salivary gland .

3- Inferior alveolar nerve(S) : enter the mandibular canal to supply theteeth of the lower jaw & emerges through the mental foramen to supply the

skin of the chin .

4- Nerve to mylohyoid muscle (motor): aris from inferior mandibular nerve

before enter the mental foramen , which supply mylohyoid m. & ant. Belly of

digastric m. .

Lec (14) the parotid & temporal region

Page 1:

slide 2 : parotid region extends between :ramus of the mandible anteriorly &

mastoid process posteriorly .

slide 3 : the structures within parotid gland are :

Superficial : facial nerve has 5 branches : temporal ,zygomatic , buccal (motor)

,mandibular , cervical .

- the middle one :retromandibular vein & lower part of superficial v. & maxillary v.

slide 4 : Deep : ECA & its termination ( maxillary a. & superficial temporal a.

Page 2 :

slide 1 : parotid gland largest slivary gland (larger than submandibular & sublingual )

- the shape of gland is wedge and It has base opposite to zygomatic arch ,and has

apex behind the angle of the mandible &front of SCM m. .

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-we can see parotid capsule enclose the parotid gland Deebly ,which come from

investing layer .

slide 3 : Glenoid process :extend upward to :superior to mandibular fossa behind the

TMJ .

- pterygoid process extend formard deeply into :ramus of mandible & runbetween ramus & medial pterygoid muscle .

- facial process forward superficially over :masseter muscle & ramus .

- the ramus of the mandible is sandwish between the masseter & medial

pterygoid muscles .

page 3 :

slide 1 : superior: EAM is external auditary meatus &TM joint

slide 2 : antero-lateral & postero-medial are based on posterior border of the

mandible .

slide 4 : stenson's duct :horizontal duct that drain it's content into oral cavity

,pass below the zygomatic arch & open into oral cavity opposite to upper 2nd

molar.

Accessory parotid duct : drain in accessory part of gland .

Page 4:

slide 2 : blood supply for parotid gland: ECA & superficial temporal a. & maxillary

a.

Venous supply : Retromandibular vein .

Innervation : parasympathetic secretomotor supply ,arise from

glossopharyngeal nerve .the nerve reach the gland via the tympanic branch ,(the

lesser petrosal n. ,the otic ganglion & the auriculotemporal n.) .

Page 5 : the temporal region

slide 1 : situated over temporal bone ,however the wing of sphenoid ,the frontal

bone ,the parietal bone are involved. Which mainly contain temporalis muscle

which the largest muscle of mastication .

_Boundaries :ant. : frontal process of zygomatic bone.

slide 2 : content of temporal region :

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- temporalis muscle :origin:comes from temporalis fossa (inferior temporal

Line) . insertion:coronoid process of the mandible . innervation:ant.

Division of mandibular Nerve to muscles of mastication . action : ant. Half of thetemporalis elvate the mandible & post. Half retract the mandible .

-temporal fascia : cover the temporslis muscle & this fascia is attach to superiortemporal line .

- Deep temporal a. & nerve: we have 2 artery come from maxillary artery & 2

nerve come from ant. Division of mandibular nerve .

slide 4 : - superior temporal a. & v. :pass post. To the TM joint &suooly the scalp and

we feel pulsation anterior the auricle .

-auriculotemporal nerve :from mandibular nerve (V3).

The mandibular nerve gives 3 branches : lingual nerve to the tonque &inferioralveolar nerve to the teeth ,&auriculotemporal nerve

-Relation from ant. To post. :TMJ >>superficial a. & v. >>auriculotemporal n.

Lec (15) (infratemporal & pteregopalatine fossa)

Boundries of infratemporal fossa:

Sup: temporal & greater wing of sphenoid & med pteregoid plate Inf: angle of the mandible or med pteregoid attachment(they are the

same) Med: lat pterygoid of sphenoid bone.

Contents of the infratemporal region:

Nerves1. Otic ganglion:

Aggregation of nerves within PNS is ganglion.

Aggregation of nerves within CNS is nucleus.

- Otic is a communicator that connects two nerves to make one tall

nerve(synapse).

Sympathetic chain is distributed in the body(3 cervical)

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Parasympathetic chain not widely disrubuted 3 or 4 in the whole body .

Caries secretomotor fibers to paratoid gland via auriculotemporal nerve.

Pregnglionic& Postganglionic:

Preganglionic fibers secretion of parotiod gland ( glossopharyngeal)

lesser petrousal nerve middle ear foramen ovale

otic ganglion

Auriculotemporal N deep to parotiod gland post

gnglionic fibers.

2. Mandibular:

n. to med pterygoid motor to :tensor tympani & tensor palatine. Meningeal n.: sensory (enter through F. spinosum but in rare cases as

mentioned in our book enter through F. ovale)

3 mastication muscles:Temporalis , masseter, lat pterygoid muscle.

3. Chorda tympani:

Carries secretomotor fibers to submandibular & sublingual glands.

Ligaments:Sphenomandibular lig : from sphenoid tubercle to lingual( meckles cartilage)

Muscles:LAT PTERYGOID MUSCLES:

1. Origin:2 heads:Sup:greater wing of sphenoid

Inf:lat surface of lat pterygoid plate.

2. insertion:2 headsneck of the mandible,articular disk of TMJ

3.innervation:

Ant. Division of mandibular nerve (V3)

4.action:

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Moves the neck forward rotrusion or protrusion.

MEDIAL PTERYGOID MUSCLES:

1. origin:tuberosity of the maxilla, medial head of lat pterygoid plate(no muscle

attatchement to the med pterygoid because its flat)

2. insertion:med of the angle of the mandible.

3. innervation:main trunk of mandibular nerve(V3)

Artries : Maxillary..

Largest branch of ECADividede by lat pterygoid. Into:

1.mandibular part:5 branches

a. Deep auricular: to EAMb. Ant. Tympanic : to lat tympanic membranec. Middle meningeal : to dura matterd. Accessory meningeal :through F.ovalee. Inf. Alveolar: through mandibular foramen

2. pterygoid part:

a. 2 deep temporal

b. pterygoid

c. Massentric?

d.buccal : supply cheek

3. Pteregopalatine part:

a. post. Sup. Alveolar: to molars & premolars

b.infraorbital

c.Desending palatine :to gingival

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lesser greater

palatine palatine

d.sphenopalatine: supply nasal cavity & paranasal sinuses.

Veins:Pterygoid venous plexus

Drain branches of max a to max v

Communicate with venous sinuses within the brain through foramen ovale

(cavernous sinuse )spread of infection from Pterygoid venous plexus to the

brain.

Pteregopalatine fossa:

Boundries:

Ant: post suface of max

Post pterygoid process

Sup: greater wing of sphenoid

Inf : ant & post pterygoid canals

Lat : opened to infratemporal fossa through pterygomax fissure

Med : vertical plate of palatine.

Contents:

Max v

Max a( 3rd part )

Pterygopalatine ganglion.

Lec (16) oral cavity & salivary glands

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Page 1 :

slide 2 : oral cavity divided inti 2 part :

- vestibule : space btwn :the lips &the cheek externally and the gum &the teeth

internally .,and contain opening of the parotid papilla (parotid duct) . it divided into 2

sulci : sup. & inf. Labialy and LU ,LL ,RU ,RL buccaly .

- the vestibule communicate with the oral cavity at :1 free way space (oral fissure)

btwn 2 lips & its 2 -3 mm gap btwn upper &lower teeth ,and present only when the

jaw muscles are relax(mastication muscle &some of supra hyoid m.) .

slide 3 : ant. : communicate with the vestibule through Free way space .

Post. : communicate with orophanyx through oropharyngeal opening .

Page 2 :

slide 1 : fully erupted of primary teeth at age of 2 y.

- 1st primary tooth to erupt is :mandibular central incisior .

-time of eruption for all teeth are explained below.

P primary (upper)

- i1 >>(10)m

- i2 >>(11) m

C >>(19)m

M1 >>(16)m

M2 >>(29)m

Primary(lower)

I1 >>(8)m

I2 >>(13)m

C>> (20)m

m1 >>(16) m

m2>>(27)m

Permanent upper

I1 >> 7 8 yr

I2 >> 8 - 9 yr

C >> 11 12 yr

P1 >>10 11 yr

P2 >> 10 12 yr

M1>> 6 7 yr

M2 >> 12 13 yr

M3 >> 17 30 yr

Permanenr lower

I1 >> 6 7 yr

I1 >> 7 8 yr

C >> 9 10 yr

P1 >> 10 12 yr

P2 >> 11 12 yr

M1 >> 6 7 yr

M2 >> 11 13 yr

M3 >> 17 30 yr

Slide 2 : innervation of the teeth : VERY IMPORTANT

The innervation for upper teeth ,PDL ,alveolar process are :

- central ,lateral incisior ,canine innervate by :ant. Sup. Alveolar( from v2

maxillary n. ) .

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- 1st & 2nd premolar & mesial half of 1st molar innervate by :mid. Sup. Alveolar

(V2) .

- Posterior teeth innervate by :post. Sup. Alveolar (V2) .

The innervation for lower teeth :

- for interior 3 teeth are innervate by : incisive verve of inf. Alveolar .

*note : inf. Alveolar n. at mental foramen opposite to 2nd premolar divide into 2

part : mental n. (goes outside or labial to teeth) & incisive n. (goes inside or

lingual to teeth) .

- for posterior teeth innervate by :inf. Alveolar n. .

The innervation for upper gingival :

- central ,lateral incisior ,canine innervate by : ant. Sup. Alveolar & infraorbital

- 1st & 2nd premolar innervate by : mid. Sup. Alveolar & infraorbital .

- Posterior teeth innervate by : post. Sup. Alveolar .

The innervation for lower gingival :

- teeth from 1 -5 are innervate by :mental branch of inf. Alveolar .

- posterior 3 molar innervate by : buucal nerve . >>from mandible n. not from

faical n. , coz buccal branch of faical n .is motor to buccinator muscle .

slide4: - type of epithelium that covered the tongue is stratified squamus

epithelium.

- phangeal part of the tongue extend to level C6 .

- surface of the tongue : palatal (dorsal) is superior , tip & margins opposite to

the teeth ,& vental opposite to floor of mouth

- the root of tongue connect it to hyoid bone (through hyoglossus )& mandible

bone (through genioglossus) .

page 3 :

slide2 :Dorsum of the tongue :

median fissure :form coz when we cut the tongue in sagital section we will find

fibrous septum and this fibrous extend to the surface will lead to form this fissure.

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- sulcus terminalis separates ant. 2/3 of the tongue from post. 1/3 . this

formed as aresult of different embryological origin of the tongue (( ant. 2/3 origin

from first brancheal arch & post 1/3 origin from 3rd brancheal arch )).

- Foramen cecum : marks origin of thyroglossal duct which duct that carry

the thyroid tissue to form thyroid gland .

- Lingual papillae:

1 filiform :smallest part &hair like shape( ) covered by stratified

squamus epithelium keratinize (SSEK).

2 fungiform : contain taste bud & covered by SSE nonkeratinize .

3 vallate or circomvellate papilla : located infront of sulcus terminalis & less

numerous .

Slide 3 : in oropharyngeal apparatus we find 4 kinds of tonsils :

Phangeal tonsils ,palatine tonsils ,lingual tonsils , tubal tonsils .

Note: in post. 1/3 of the tongue we find taste bud .

Slide 4: frenulum connects the tongue to floor of the mouth.

- fimberiated fold :formed because the MM of the tongue different from

dorsum & the ventral ,and when it fuse to each other form what we call it

fimberiated fold .

- between the frenulum & fimberiated we find Deep lingual v. & a. which

are branches from lingual artery & vein >>which come from ECA .

page 4 :

slide 2: muscles of the tongue :2 type : Intrinsic & Extrinsic muscles

- all intrinsic muscles are innervate by Hypoglossal n. (XII)

- 5 muscle of Extrinsic type are : genioglossus ,hyoglossus

,styloglossus ,palatoglossus ,& the 5th muscle is small slip muscle located medial to

hypoglossus muscle & extend from the lesser horn of hyoid bone into tongue which wecall it Condroglossus .

- All Extrinsic muscles are innervate by Hypoglossal n. except one muscle :the

palatoglossal muscle which innervate by pharyngeal plexus .

Slide 3: Note : the detailed anatomy of all of the muscles of the tongue are

summarized in page ((very important)) .

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Slide 4: innervation to the tongue : the General sensory toant. 2/3 is lingual

nerve from mandibular n. &the General sensory to post. 1/3 is

glossopharyngealnerve . but the special sensory for ant. 2/3 is corda

tympani (from facial n). & post. 1/3 innervate by glossopharyngeal n.

Page 5 :

Slide 1: arterial supply :

Lingual a. ( the main one) :come from ant. Branches of ECA .

- when the lingual a. pass deep to hyoglossal m. gives 3 branches :

1 Dorsal lingual a. : supply post. 1/3 of the tongue .

2- Deep lingual a. : supply ant. 2/3 of the tongue .

3- suplingual a. :supply floor of the mouth .

- tonsillar a. :comes from facial artery and supply lingual tonsil .

- ascending pharyngeal a. :supply some part of the posterior part of the tongue.

Slide 2 : Submental L.N :in the submental triangle .

Submandibular L.N :in the submandibular triangle .

Slide 3 :hypercontraction :mean the tongue move forward.

Slide 4: the pill will absorbed through the smooth & thin mucosal and enter toDeep lingual vein .

Page 6 :

Slide 1: Submandibular gland: mixed gland but the mainly one is serous (coz

has protein ex: amelays). Sublingual gland: mixed gland but mainly mucous

- Rest on post. Border of : mylohyoid muscle .& this mylohyoid muscle divide

the submandibular gland into superficial & deep parts .

-

- the relations of submadibular & sublingual glands are encluded in

last2 page of lecture # 18 .

-

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slide 2: submandibular duct (Warton's):open in floor of the mouth just beside

the frenulum , & run deep to the sublingual gland >>then run to the hyoglossus

muscle .

Lec (17) The nose and the palate

The nose:

the nose is between the cranial cavity superiorly and the oral cavity inferiorly.

Lined by the M.M from the inside(which type?)which is composed of 2

types:1.olfactoroy mucosa, containing the olfactory epithelium which is located

in the upper 1/3 of the nasal cavity. It is seudostratified columnar nonciliated

epithelium, and has no goblet cells.

2.respiratory mucosa containing the respiratory epithelium, which is

located in the lower 2/3 of the nasal cavity. It is seudostratified columnar ciliated

epithelium, and has goblet cells.

The external nose:

the bones of the external nose are:

1.frontal process of?? The maxilla. 2. the nasal bone.

Cartilages:

The septal cartilage forms the ant. Part of the nasal septum and this cartilage

fades in age.

The lower lat. Cartilage has another name which is the greater alar.

The lesser alar is behind the greater alar.

Nasal cavity:

The vestibule is lined by the skin (stratified squamous epithelium)

The sup. The mid. Chonchae are from the ethmoid bone, however the inf.

chonchae is a separate bone.

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The roof: is the bony part that separates the nasal cavity from the ant. Cranial

fossa.

The floor: separates the nasal cavity from the oral cavity. And consist of??

The palatine process of max. and the horizontal process of palatine.

Nasal chonchae and meatus:

Every chonchae projects downward to form the meaus and they open into the

paranasal sinuses.

Sup. Meatus:?? Has 2 openings for the post. Ethmoidal air cells

Mid. Meatus:?? frontonasal duct, max. sinus, middle ethmoidal and ant.

Ethmoidal...and here there is an elevation called bulla ethmoidalis(not sure of

the spelling), and beneath I we have the semi lunar hiatus, and on its tip we theopening of the frontonasal duct and the ant. Ethmoidal cells.and on its end we

have the max. sinus.

Inf. Meatus:?? Has no air sinuses but has nasolacrimal duct.

Spheno-ethmoidal recess:

Receives:?? Sphenoid air cells.

Arterial blood supply:

The nasal cavity is the second richest area in the body of bld. Supply after the

skull.

1.sphenopalatine a.

Terminal branch of?? Third part of the max. a.

Enters through?? Sphenopalatine foramen which is post. To the mid.

Chonchae

Supply?? The post. Aspect of the nasal septum(nasal cavity and the paranasal

sinuses)

2. sup.labial a.

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From? Facial a.

Supply?? The ant. Aspect of the nasal septum

Theses first 2 arteries can anastomose in the nasal cavity with each other.

3.ethmoidal a.

From?? opthalmic a.

Supply?? The upper part of the nasal cavity (olfactory epithelium)

4.greater palatine a.

From?? 3rd part of max. a.

Supply?? The floor of the nasal cavity( hard palate), in other words the lower

part of the nasal cavity.

Venous drainage:

The pterygoid venous plexus is located in the infra temporal fossa. And drains

into the max. v. which joins the superficial temporal v. to form the retro

mandibular v.

Nasal bleeding:

From septal braches of?? The sup. Labial a. and the sphenopalatine a.

Direct pressure with the head at?? The neutral position.

Paranasal sinuses:

The respiratory epithelium is ofwhich type?? Seudostratified columnar.

Summary:

Frontal air sinus:-middle meatus through the frontonasal duct and the ant.

Ethmoidal air cells

Middle air sinus:- ethmoidalis in he middle meatus

Post. Sinus:-sup. Meatus

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Sphenoid air cell:- sphenothmoidal recess

Max. sinus:- lower part of mid. Meatus.

Sinusitis & meningitis:

in children, the bony floor between the cranial cavity and the nasal cavity is soft

and thin, and sometimes absent.and any infection to the sphenoid or ethmoid

air cells lead to the erosion of the bony part to the brain leading to meningitis

and this may lead to the production of pus in the cranial cavity (sinusitis)

hard palate:

formed by?? Palatine process of max. and horizontal process

floor of?? The nasal cavity.

Soft palate:

Expanded tendon of?? Tensor velli palatitni.

Both the palatoglosis and the palatopharyngeus form?? Both the arches.

All the muscles of the palate are innervated by the pharyngeal plexsusexcept the tensor veli palatine which is innervated by the mandibular

trigeminal( n. to the med. Pterygoid).

But in the muscles of the tongue, all are innervated by the hypoglossal

n. except the palatoglosal by the pharyngeal plexsus

Arterial bld. supply:

Descending palatine a. is from?? The max. a.

Greater palatine a.: supply the hard palate

Lesser palatine a. : supply the soft palate

Innervations to palate:

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1. greater palatine n.: through?? Greater palatine foramensupply??hard palate and the gum of the upper teeth

2.lesser palatine n.: through?? Lesser palatine foramen

Supply?? The soft palate

3.nasopalatine n.: through?? Incisive foramen

Supply?? Primary palate( which is a triangular area forming

the ant. Part of the hard palateand then this n. continues as the Incisive n.

Structures on the palate:

Rugae: thickness in the mucus membrane mostly in the primary palate.

Vibrating line: is between?? The movable and unmovable parts of the softpalate.

Lies behind??The junction between the hard and soft palates the

denture should be?? Between The junction between the hard and soft

palates and the vibrating line.

i.e., the denture mustnt be else where because itll fall.

Cleft palate:

Prevalence?? Highest in the native Americans

On page 8 (the last slide), look at figure E this is a rare condition where the

cleft is in the primary palate alone separated from the secondary palate.

Fig. C: unilat. Cleft, where as in fig. D: bilat. Cleft.

Lec (18) The Larynx

this is summary of the larynx that the Dr does not explain it in the lecture

the larynx open above into laryngeal part of the pharynx & below is

continuous with the trachea , the larynx is covered infront by the infrahyoid strap

of muscles& at the side by the thyroid gland .

cartilages of the larynx :

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- thyroid cartilage : the largest one &consist of 2 laminae of hyaline

cartilage ,that meet in the adam's apple , posterior border extend from superior

cornu (upward) & inferior cornu (downward), and we will find in outer surface of

the lamina what we call it oblique line (attachment muscles) .

- cricoid cartilage : hyaline cartilage & shaped like signet ring ,having

posteriorly broad plate & shallow arch anteriorly, the posterior broad plate is

lamina ,which has upper articulation with the arytenoids cartilage (all these joint

are synovial ) .

- arytenoid cartilage :this cartilage articulate with upper border of the

lamina of the cricoid cartilage ,arytenoid cartilage has an apex above articulate

with corniculate cartilage ,& has a base below articulate with the lamina of the

cricoid cartilage ,and has vocal process & muscular process and the last one

attachment to the posterior & lateral cricoarytenoid m. .

- corniculate cartilage : they give attachment to ayroepiglottic folds .

- cuneiform cartilage : serve to strengthen of the aryepiglottic folds.

- Epiglottis : its stalk is attached to the back of the thyroid cartilage .

membrane & ligament of the larynx :

- thyroidcartilage :it will be thickened in the midline to form median

thyrohyoid ligament .

- cricotracheal ligament :connect the cricoid cartilage to the 1st

ring of thetrachea .

- Quadrangular membrane :extends between the epiglottis & the

arytenoids cartilage .

- Cricothyroid ligament : the lower margin is attached to the upper border

of the cricoid cartilage , the superior margin of the ligament ascends on the medial

surface of the thyroid cartilage.

The piriform fossa :is a recess on either side of the fold and inlet ,&it is

bounded medially by the aryepiglottic fold and laterally by the thyroid cartilage &thyrohoid membrane .

The muscles of the larynx are exist in the table in page .

The movements of the vocal cord are not encluded in the

lecture

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Lec #(19) The Pharynx

This is a summary for lecture 19 the pharynx I hope you'll get the benefit from

it, you can read it first and then refer to your slide for revision, it worth lookingto some pictures while reading it. Good Luck =

The pharynx (C1 to C6): is a funnel shaped ( ) fibromusculartube (made of muscles and fibrous tissue) that extends from the base of the

skull (performed by the body of sphenoid at the level of C1) and continues with

esophagus at the level of C6.

Based on the extent the pharynx is divided into 3 regions:

1. Nasal: nasopharynx is an area behind the nasal cavity.2. Oral: oropharynx is an area behind the oral cavity; the oral cavity has 2

openings oral fissure and oropharyngeal isthmus.3. Laryngeal: laryngeo pharynx is an area behind the larynx, it extents from

the upper part of the epiglottis all the way to the esophagus.

Note: the picture in the first slide is a posterior view and they've cut the

pharynx in the middle.

Since the pharynx is a tube it has anterior, posterior and two lateral walls;

Ant wall anteriorly we have no wall because it communicates with the nasal

cavity superiorly, oral cavity in the middle and the larynx inferiorly.

Lat and post walls they are made up of:

1. mucous membrane covered by2. the fibrous covering underneath it3. the muscles

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Muscles of the pharynx:

We have 6 muscles: 3 x 3

- The longitudinal 3 muscles are named so because their fibers run in alongitudinal direction.

- The main 3 muscles (sup, mid, inf constrictors) are the 3 constrictors theyare circular ones forming mainly the walls of the pharynx.

Some times the constrictor muscles (sup, mid, inf) overlap each other in a way

we call it inferior to superior direction (the inf one overlaps the middle one which

in turn overlaps the superior one). These constrictor muscles run in circles but

once they reach the posterior border they turn upward to be inserted on the

pharyngeal tendon. The pharyngeal tendon is a saggital plane (located in the

middle of the posterior wall) posteriorly in the wall of the pharynx and it is a

fibrous tendon or tendinous sheath.

The action of these constrictors is the production of swallowing, when you

swallow a piece of food the sup constrictor contracts first to push it down then

the middle constrictor contracts and finally the inf constrictor to push it to the

esophagus.

The innervation of pharyngeal muscles is by the pharyngeal plexus except the

stylopharygeus muscle.

The story of innervation:

The CN of accessory carried by the vagus nerve until they reach the wall of

the pharynx to form a plexus with the glossopharyngeal nerve to form the

pharyngeal plexus (CNs 9 10 11) sends fibers to supply the walls of the

pharynx.

So:

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The innervation pharyngeal plexus

The main origin CN of accessory carried by the vagus nerve to pharyngeal

plexus.

The origin of the muscles of the pharynx:

Each muscle has 2 sites of origin:

1. Superior constrictor it originates from the the posterior lower borderof medial pterygoid plate, then it goes down to the pterygomandibular

ligament or raphe (in dentistry) and this raphe is very important fordentists because it is separated from the mandible by a mass of fat(adipose tissue), so when you want to anesthetize the inferior alveolarnerve (inferior alveolar block) you always insert the needle in an areabetween the ramus of the mandible and the pterygomandibular raphe, soyou put your finger on the posterior wall of the ramus of the mandible andinsert the needle halfway between the pterygomandibular raphe and theramus of the mandible.

So the origin of the superior constrictor is the medial plate of pterygoid and

the pterygomandibular raphe.

Note: the pterygoid muscle goes from the lateral pterygoid plate.

Note: the superior constrictor muscle is posterior to the pterygomandibluar

raphe while the buccinator (the muscle of the cheek) is anterior to it.

2. The middle constrictor originates from the stylohyoid ligament andlesser and greater horns of hyoid bones.

3. Inferior constrictor the thyroid cartilage (the lamina of the thyroidcartilage) and cricoid cartilage.

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The inferior constrictor has 2 origins so that's why they divide it into two parts:

- The superior one they call it the thyropharyngeus muscle coz it'sfrom the thyroid and the its fibers go superiorly.

- The inferior part from cricoid we call it cricopharyngeus muscleand its fibers are directed downward.

The area between them is an area of weakness, it's a weak triangular shaped

area we call it killian's dehiscense

What happens in killian's dehiscence is that the mucous membrane (the internal

aspect of the pharynx) along with the fibrous tissue can go out from the pharynx

forming the pharyngeal pouch

This pharyngeal pouch sometimes produces dysphasia (difficulty in swallowing)

and it also leads to gag reflex and irritation.

Most of the times, this pouch increases and goes to the left (and it can go to the

right but mostly to the left) and produces a pressure upon and under the

esophagus that leads to further complication. Treatment to this condition issurgical excision of this pouch

Killians area: weak triangular area present between the two parts of the

inferior constrictors

The other three muscles that we called them the longitudinal muscles

are:

1. The stylopharyngeus m.: from the posterior border of the styloidprocess to the posterior border of the thyroid cartilage.

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Note: the styloglossus muscle runs from the anterior border of the styloid

process to the tongue while the stylohyoid ligament runs from the styloid

process to the hyoid bone.

2. The salpingopharyngeus muscle: From the pharynx there is apharyngeaoauditory tube, this tube connects the middle ear with thepharynx to produce balance in the tympanic membrane, when the airenters the auditory meatus and the tympanic membrane is closed it willproduce a pressure so the air enters from inside through the pharynx toproduce balance in the tympanic membrane, the medial end of theauditory tube that opens in the pharynx contains a very small muscle thatdescends in the pharynx it is called the salpingopharyngeus muscle and itblends with another muscle from the soft palate descending to the

thyroid cartilage called the palatopharyngeus muscle.

3. palatopharyngeus muscle: so the salpingopharyngeus blends oremerges with the palatopharyngeus muscle that descends from the softpalate (specifically the palatal aponeuorosis that comes from tensor vellipalatini) all the way down to the lamina of thyroid cartilage (this is theinsertion of the palatopharungeus muscle).

The salpingopharyngeus muscle and the palatopharyngeus muscle when

covered by the mucous membrane it produces folds, so when you view them in

the oral cavity the view will be as fold, that's why they are called in the oral

cavity as the salpingopharygeus and palatopharengeus folds.

Remember the location of the palatine tonsils between 2 muscles palatoglossus

and palatopharygeus, the mucous membrane that covers them will be named as

palatoglossus and palatopharyngeus folds beneth them the palatoglossus and

palatopharyngeus muscle respectively.

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Since these muscles are longitudinal their job is to elevate the pharynx, and

they receive their nerve supply from the pharyngeal plexus except the

stylopharyngeus muscle that is innervated by the glossopharyngeal nerve CN 9

and this is the only muscle innervated by the glossopharyngeal nerve (the only

motor innervation), because it carries general sensations to the oropharynx and

the posterior third of the tongue.

The nasopharynx (C1 to C2)

The nasopharynx is posterior to the nasal cavity and just above the soft palate;

its boundaries are from the post. wall of the nasal conchae (remember that the

post. Wall of the nasal conchae is the final extension of the nasal cavity (nasal

cavity extent from the vestibule all the way to the post. wall of the nasal

conchae))

It is lined by a respiratory epithelium( ciliated epithelium) since it is behind the

respiratory apparatus while the oropharynx and the laryngeopharynx are lined

by stratified squamous epithelium because it is part of the digestive tract.

The contents:

1. The auditory tube or the pharyngeo auditory tube (the lateralopening): when it enters the pharynx it makes its medial end as animpression on the wall, this impression is an elevation the tubal elevation(it's the medial ending of the auditory tube pressuring on the walls of thenasopharynx)

2. Tubal tonsils (One on the right and one on the left): aggregation oflymph nodes surrounding the medial end of the auditory tube (the tubalelevation) and if you cut the mucous membrane there you will find a smallaggregation of lymph nodes.

3. The pharyngeal tonsil (adenoid): another aggregation of lymph

nodules but this time is larger located in the roof of the submucosa of thenasopharynx ( the roof is formed by the body of sphenoid)

The oropharynx (C2 to C3)

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The oropharynx (opposite to C2 to C3) is located post. to the oral cavity and it is

opened from the oropharyngeal isthmus (the isthmus is between the oral cavity

and the oral part of the pharynx)

The boundaries of the oropharyngeal isthmus:

- Inferiorly The sulcus terminalis (the boundary between the ant. 2/3and the post. 1/3 of the tongue)

- Laterally the palatoglossal fold underneath it the palatoglossus muscle

- Sup. The junction between hard and soft palate

The oropharynx extents from:

The roof: the soft palate

The floor: the post. 1/3 of the tongue inferiorly along with the epiglottis and the

vallecula (a depression between the tongue and the epiglottis, there are 2

valleculae sperated from each other by the glossoepiglottic fold).

The most important structure in the oropharynx is the palatine tonsils, we

recognize these tonsils from the folds, the first one extent from the soft palate

to the tongue the palatoglossal fold, the second one from the soft palate to the

pharynx the palatopharyngeal fold, between them and on the superior

constrictor muscle the palatine tonsils rest.

The palatine bed or tonsilar sinus: this area where the palatine tonsils are

laid.

- The roof of the palatine bed: palatoglossal muscle and fold- Ant: Palatopharyngeal muscle and fold- The floor: superior constrictor muscle

Relations to the palatine tonsils:

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Ant: palatoglossual fold

Post: palatopharyngeal fold

Sup: the soft palat

Inf: post. Third of the tongue

Medially: the cavity of oropharynx

Laterally: superior constrictor muscle

Tonsilitis and tonsillectomy

Tonsillitis is the inflammation of the tonsils, however there is a common

mistake referring to the palatine tonsillitis as tonsillitis (without saying

palatine) because the inflammation occurs mostly in the palatine tonsils.

So the inflammation of the palatine tonsillitis we generally call it tonsillitis

Tonsillectomy is the surgical removal of tonsils, and again we generally call

the palatine tonsillectomy as tonsillectomy (without saying palatine).

Whether to remove the tonsils or not it's a debate between surgeons; tonsils

are part of the immune system (considering that the tonsils are the first

defense line in the body) and the internal body (i.e the digestive tract) will be

more exposed to infections when removed so that's why some surgeons say

that it's unnecessary to remove it while others say that chronically (severe

and continuous) inflamed tonsils are sites of recurrent inflammation.

Adenoiditis: The inflammation of the pharyngeal tonsils

The laryngeopharynx (C4 to C6)

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The larngeopharynx extends from the epiglottis all the way down to cricoid

cartilage and lined by stratified squamous epithelium.

It contains a small depression called the piriform fossa

The piriform fossa: is a small depression from the aryepiglottic fold (it's a

membrane that connects the arytenoid cartilage to the epiglottis) located

medial to the pririform fossa, laterally we have the lamina of thyroid

cartilage, it is a very important area because it prevents foreign bodies and

structures from being swallowed.

Note: you can locate this fossa from the picture provided in the slide

The prirform fossa is a very important and dangerous area because the

internal laryngeal nerve passes in this fossa to get inside the larynx just

beneath the mucous membrane, if you swallow a sharp thing or a chicken

bone it will tear the mucous membrane in the piriform fossa and the internal

laryngeal nerve gets injured so paralysis in the larynx will occur superior to

the vocal cords.

The story of the origin of the internal laryngeal n. is as followed:

The vagus nerve gives of the sup. Laryngeal n. (it innervates the area

above the vocal cords) it divides into the internal and external laryngeal

nerves.

The sensory innervation to the pharynx:

- The nasopharynx is innervated by V2 (maxillary nerve) of trigeminal n.

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- The oropharyngeal is innervated by the glossopharyngeal nerve (youcan remember this information by remembering that the post. 1/3 ofthe tongue that is innervated by the glossopharyngeal n. is locatedthere).

-The laryngeopharynx is innervated by the vagus nerve.

The motor innervation to the pharynx is by the pharyngeal plexus to all

the muscled of the pharynx except the stylopharyngeus muscle.

Gag reflex:

Have you ever put your finger in the back most part of your mouth reachingthe pharynx?

If you do so you certainly felt that you want to vomit, this is called the gag

reflex, this condition happens because you are irritating the

glossopharyngeal nerve, so the nerve gives signals to the brain, then the

brain gives signals to the CN of accessory, then the accessory n. sends its

fibers through the vagus n. to the pharyngeal plexus, then this plexus gives

its fibers to the constrictors to contract together fastly, then you start to feel

that you want to vomit.

Note: glossopharyngeal sending the information and the brachial plexus

carrying the motor innervations.

Note: The gag reflex in the oropharynx involves both sensory and motor

innervations and this is a very good example in how the sensory and motor

innervations cooperate with each other.

Relations of the pharynx

Post: The retropharyngeal space and prevertebral fascia of the deep cervical

fascia

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Lat: Carotid sheath along with the glossopharyngeal n.

Ant:

1. nasal cavity

2. soft palate

3. oral cavity

4. posterior 3rd of the tongue

5. epiglottis

6. larynx

The pharyngeal gaps

Spaces created by the pharyngeal constrictor muscles when the constrictors

close on one another and there are certain structures that pass through

them:

1. Above sup. Constrictor m.- Auditory tube.

-Levator velli palatini (elevates the soft palate).

- Tensor velli palatine.2. Between the sup. & mid. Constrictors m.- stylopharyngeus membrane.3. Between the mid. & inf. Constrictors m.- Internal laryngeal n- Sup. Laryngeal n. . . (The artery that passes with it is the sup. Laryngeal

artery from the superior thyroid artery and it supplies the larynx).4. Below inf. Constrictor m.- Recurrent laryngeal n. (it comes from the vagus and return up to the

larynx)

-Inferior laryngeal artery (to the lower part of the larynx) from the inferiorthyroid artery.

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DONE BY : BILAL AL-OMARI

2nd Head&Neck

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