LARYNX & PHARYNXLARYNX & PHARYNXAnatomy & PhysiologyAnatomy & Physiology

Dr. M. AbdelDr. M. Abdel--Rauf MasoudRauf Masoud

Professor of OtolaryngologyProfessor of Otolaryngology

Ain Shams UniversityAin Shams University

LARYNX (Voice Box)LARYNX (Voice Box)AnatomyAnatomy

Larynx is formed of:Larynx is formed of:

�� Skeleton:Skeleton: Cartilages.Cartilages.

�� Membranes & ligaments.Membranes & ligaments.

�� Muscles.Muscles.�� Muscles.Muscles.

�� Lining: Lining: Mucous membrane (st. sq. ep. Mucous membrane (st. sq. ep. & & ciliatedciliated col. ep.) col. ep.)

Cartilages of the larynxCartilages of the larynx

�� UnpairedUnpaired–– ThyroidThyroid

–– CricoidCricoid

–– EpiglottisEpiglottis

�� PairedPaired–– ArytenoidsArytenoids

–– CorniculateCorniculate

–– CuneiformCuneiform

Thyroid cartilage:Thyroid cartilage:

Cricoid cartilage:Cricoid cartilage:

Epiglottis:Epiglottis:

Arytenoid cartilages:Arytenoid cartilages:

Ligaments and Ligaments and

membranesmembranes

�� Extrinic:Extrinic:

–– Thyrohyoid Thyrohyoid membranemembranemembranemembrane

–– Cricotracheal Cricotracheal membranemembrane

–– Hyoepiglottic Hyoepiglottic ligamentligament

Ligaments and Ligaments and

membranesmembranes

Intrinsic:Intrinsic:�� Elastic membrane:Elastic membrane:

–– Upper partUpper part

–– Conus elasticus Conus elasticus –– Conus elasticus Conus elasticus (thyro(thyro--cricoid cricoid membrane)membrane)

–– Deficient at the Deficient at the laryngeal ventriclelaryngeal ventricle

�� ThyroThyro--epiglottic & epiglottic & thyrothyro--cricoid cricoid ligaments.ligaments.

Cavity of the Cavity of the LarynxLarynx

�� From the inlet to From the inlet to the tracheathe trachea

�� Divided into three Divided into three parts:parts:parts:parts:–– SupraglotticSupraglottic–– GlotticGlottic

��Membranous Membranous (phonatory)(phonatory)

�� Cartilagenous Cartilagenous (respiratory)(respiratory)

–– SubglotticSubglottic

The GlottisThe Glottis

Muscles of the LarynxMuscles of the Larynx

�� Intrinsic:Intrinsic:

–– Abductors of VF.Abductors of VF.

–– Adductors of VF.Adductors of VF.–– Adductors of VF.Adductors of VF.

–– Tensors of VF.Tensors of VF.

�� Extrinsic:Extrinsic:

–– Strap muscles.Strap muscles.

–– Pharyngeal muscles.Pharyngeal muscles.

Intrinsic musclesIntrinsic muscles

Change the position of the VFsChange the position of the VFs

Adductors of the VFsAdductors of the VFsBring the VFs to midline.Bring the VFs to midline.

Abductors of the VFsAbductors of the VFsTake the VFs laterally.Take the VFs laterally.

Tensors of VFsTensors of VFsStretch the VFs. Stretch the VFs.

�� CricoCrico--thyroid m.thyroid m.

Extrinsic MusclesExtrinsic MusclesChange the position of the Change the position of the

larynx as a wholelarynx as a whole

�� Strap muscles:Strap muscles:

–– SternothyroidSternothyroid–– SternothyroidSternothyroid

–– ThyrohyoidThyrohyoid

�� Pharyngeal muscles:Pharyngeal muscles:

–– StyloStylo--pharyngeuspharyngeus

–– PalatoPalato--pharyngeuspharyngeus

–– Inferior constrictorInferior constrictor

Nerve supplyNerve supply

�� Rec. laryngeal n.Rec. laryngeal n.1. Motor to all muscles except 1. Motor to all muscles except ??????

2. Sensory to mm below vocal 2. Sensory to mm below vocal 2. Sensory to mm below vocal 2. Sensory to mm below vocal folds.folds.

�� Sup. laryngeal n.Sup. laryngeal n.1. Motor to cricothyroid.1. Motor to cricothyroid.

2. Sensory to mm above 2. Sensory to mm above vocal folds.vocal folds.

Larynx in infants:Larynx in infants:

�� Position: Higher.Position: Higher.

�� Shape: Funnel.Shape: Funnel.

�� Cartilages: Soft.Cartilages: Soft.�� Cartilages: Soft.Cartilages: Soft.

�� Epiglottis: UEpiglottis: U--shaped.shaped.

�� Submucosa: Lax.Submucosa: Lax.

Airway can be easily Airway can be easily obstructed!!!obstructed!!!

LarynxLarynxPhysiologyPhysiology

�� Protection.Protection.

�� Phonation.Phonation.

Respiration.Respiration.�� Respiration.Respiration.

�� Fixation of Fixation of thorax thorax (straining).(straining).

PhonationPhonation

�� Aerodynamic Aerodynamic theorytheory

�� Bernoulli effectBernoulli effectBernoulli effectBernoulli effect

�� Mucosal vibrationMucosal vibration

PHARYNXPHARYNXAnatomyAnatomy

�� From skull base to From skull base to C6C6

�� Funnel shapedFunnel shaped

�� About 10About 10--12 cm12 cm

�� Divided intoDivided into

–– NasopharynxNasopharynx

–– OropharynxOropharynx

–– LaryngopharynxLaryngopharynx

NasopharynxNasopharynx (Postnasal space)(Postnasal space)

�� Behind the nose.Behind the nose.

�� From skull base to level of soft palate.From skull base to level of soft palate.

�� Basi occiput & sphenoid, C1.Basi occiput & sphenoid, C1.

OropharynxOropharynx

�� Above: soft palateAbove: soft palate

�� Below: EpiglottisBelow: Epiglottis

�� CC22,,33

�� Laterally: tonsilsLaterally: tonsils�� Laterally: tonsilsLaterally: tonsils

LaryngoLaryngo--(hypo(hypo--)pharynx)pharynx

�� From epiglottis to From epiglottis to lower cricoidlower cricoid

�� C3C3--66

�� Divided into:Divided into:

–– Pyriform fossaPyriform fossa

–– PostcricoidPostcricoid

–– Posterior pharyngeal Posterior pharyngeal wallwall

Structure of the PharynxStructure of the Pharynx

�� Mucous membraneMucous membrane

�� Pharyngobasilar fasciaPharyngobasilar fascia

�� Muscular coatMuscular coat�� Muscular coatMuscular coat

�� Bucopharyngeal faciaBucopharyngeal facia

Structure of the Pharynx Structure of the Pharynx cont.cont.

�� Mucous membrane:Mucous membrane:

–– Ciliated columnar epitheliumCiliated columnar epithelium

–– SSESSE–– SSESSE

–– TransitionalTransitional

�� SubepithelialSubepithelial lymphoid tissue:lymphoid tissue:((Waldeyer’sWaldeyer’s Ring)Ring)

�� Mucous gl. & minor salivary gl.Mucous gl. & minor salivary gl.

Muscles of the PharynxMuscles of the Pharynx

Two layers:Two layers:––External (circular)External (circular)

Sup. ConstrictorSup. Constrictor��Sup. ConstrictorSup. Constrictor

��Middle ConstrictorMiddle Constrictor

�� Inferior ConstrictorInferior Constrictor

–– Internal (Longitudinal)Internal (Longitudinal)

Constrictor muscles of the Constrictor muscles of the Pharynx:Pharynx:

�� 3 muscles 3 muscles telescoped into telescoped into each other.each other.each other.each other.

�� Inferior constrictorInferior constrictor

has 2 parts:has 2 parts:

--ThyroThyro--pharyngeus.pharyngeus.

--CricoCrico--pharyngeus.pharyngeus.

Internal group:Internal group:

�� StylopharyngeusStylopharyngeus

�� SalpingeopharySalpingeophary--�� SalpingeopharySalpingeophary--ngeusngeus

�� PalatopharyngeusPalatopharyngeus

Nerve Supply:Nerve Supply:

�� Sensory:Sensory:

99thth & 10& 10thth cranial n.cranial n.

�� Motor:Motor:

All muscles are supplied by pharyngeal All muscles are supplied by pharyngeal All muscles are supplied by pharyngeal All muscles are supplied by pharyngeal plexus (9plexus (9thth, 10, 10thth & 11& 11thth))

Cricopharyngeus also has rec. laryngeal n.Cricopharyngeus also has rec. laryngeal n.

�� Autonomic:Autonomic:

SympatheticSympathetic (symp. c(symp. chainhain + plexus + plexus around carotid a.)around carotid a.)

ParasympatheticParasympathetic (9(9thth & 10& 10thth + 7+ 7thth ))

Adenoids:Adenoids:

Palatine Tonsils:Palatine Tonsils:

Lingual Tonsils:Lingual Tonsils:

Palatine Tonsils:Palatine Tonsils:

�� In between pillars.In between pillars.

�� Surface: St. sq. ep., crypts.Surface: St. sq. ep., crypts.

�� Has capsule.Has capsule.

Blood supply of the tonsils:Blood supply of the tonsils:

�� TonsillerTonsiller artery (branch of facial artery (branch of facial artery; main blood supply).artery; main blood supply).

�� Branches from:Branches from:�� Branches from:Branches from:

11. Ascending pharyngeal artery.. Ascending pharyngeal artery.

22. Palatine arteries.. Palatine arteries.

33. Lingual artery.. Lingual artery.

Palate:Palate:

Muscles of the soft palate:Muscles of the soft palate:

�� Tensor palati.Tensor palati.

�� Levator palati.Levator palati.

�� Musculus uvulea.Musculus uvulea.�� Musculus uvulea.Musculus uvulea.

�� Palatoglossus.Palatoglossus.

�� Paltopharyngeus.Paltopharyngeus.

All are supplied by pharyngeal All are supplied by pharyngeal plexus except tensor palati plexus except tensor palati (mandibular division of trigeminal).(mandibular division of trigeminal).

Muscles of the soft palate:Muscles of the soft palate:

Spaces around the pharynxSpaces around the pharynx

�� ParaPara--pharyngeal spaces pharyngeal spaces (one on (one on each side of upper part of the each side of upper part of the pharynx).pharynx).pharynx).pharynx).

�� RetroRetro--pharyngeal space pharyngeal space (between (between posterior pharyngeal wall & preposterior pharyngeal wall & pre--vertebral fascia).vertebral fascia).

ParaPara--pharyngeal spacepharyngeal space

�� Potential space Potential space lateral to upper lateral to upper pharynxpharynx

Inverted three Inverted three �� Inverted three Inverted three sided pyramid with sided pyramid with floor at skull base, floor at skull base, tip at hyoidtip at hyoid

Boundaries of PPS Boundaries of PPS (cont.)(cont.)

Superior (base):Superior (base):

�� Small portion of Small portion of temporal and temporal and temporal and temporal and sphenoid bonessphenoid bones

�� Includes the carotid Includes the carotid canal, jugular canal, jugular foramen, and foramen, and hypoglossal foramenhypoglossal foramen

Boundaries of PPS:Boundaries of PPS:

�� Inferior (Apex): Inferior (Apex): junction of posterior junction of posterior belly of the belly of the digastricdigastric and greater and greater cornucornuof hyoidof hyoidof hyoidof hyoid

�� Laterally:Laterally: fascia overlying medial fascia overlying medial pterygoidpterygoid muscle, muscle, ramusramus of mandible, of mandible, and fascia overlying and fascia overlying retromandibularretromandibularparotid. Below the level of mandible is parotid. Below the level of mandible is the post. belly of the post. belly of digastricdigastric

Boundaries of PPS Boundaries of PPS (cont.)(cont.)

�� Medially:Medially: buccopharyngealbuccopharyngeal fascia fascia over superior constrictor (pharynx)over superior constrictor (pharynx)

�� Anterior:Anterior: pterygomandibularpterygomandibular rapheraphe�� Anterior:Anterior: pterygomandibularpterygomandibular rapheraphe

�� Posterior:Posterior: dorsal layer of fascia of dorsal layer of fascia of the carotid sheath, cervical vertebrae the carotid sheath, cervical vertebrae and and prevertebralprevertebral musclesmuscles

Contents of PPS Contents of PPS (Pre(Pre--styloidstyloidcompartment)compartment)

�� FatFat

�� Retromandibular parotidRetromandibular parotid

�� Lymph nodesLymph nodes�� Lymph nodesLymph nodes

Contents of PPS Contents of PPS (Post(Post--styloidstyloidcompartment)compartment)

�� Internal carotid arteryInternal carotid artery

�� Jugular veinJugular vein

�� Sympathetic chainSympathetic chain�� Sympathetic chainSympathetic chain

�� Cranial nerves IXCranial nerves IX--XIIXII

�� Lymph nodesLymph nodes

Retropharyngeal spaceRetropharyngeal space

�� Between prevertebral and Between prevertebral and buccopharyngeal fasciabuccopharyngeal fascia

�� Contents: Retropharyngeal LNsContents: Retropharyngeal LNs�� Contents: Retropharyngeal LNsContents: Retropharyngeal LNs

�� Strictly separated in midlineStrictly separated in midline

�� Disappear at 3Disappear at 3--4 years of life 4 years of life

Functions of the Pharynx:Functions of the Pharynx:

�� Part of the digestive system:Part of the digestive system:

a. Saliva.a. Saliva.

b. Deglutition.b. Deglutition.b. Deglutition.b. Deglutition.

�� Part of the respiratory system:Part of the respiratory system:

a. Breathing.a. Breathing.

b. Ventilation of ME (Eustachian tube).b. Ventilation of ME (Eustachian tube).

�� Role in speech.Role in speech.

Deglutition:Deglutition:

�� Three phases:Three phases:

–– Oral:Oral:

�� PreparatoryPreparatory�� PreparatoryPreparatory

�� TransportTransport

–– PharyngealPharyngeal

–– EsophagealEsophageal

�� Oral is voluntary, pharyngeal and Oral is voluntary, pharyngeal and esophageal are involuntaryesophageal are involuntary

Phases of deglutition:Phases of deglutition:

Role in Speech:Role in Speech:

�� Some consonants are produced at Some consonants are produced at the soft palate region; velar (the soft palate region; velar (KhKh, , GhGh).).

�� Resonance:Resonance:�� Resonance:Resonance:

a.a. NasopharynxNasopharynx, nasal cavity & sinuses , nasal cavity & sinuses act as a resonance box.act as a resonance box.

b.b. Soft palate opens the Soft palate opens the velopharyngealvelopharyngealvalve in resonating consonants (n, valve in resonating consonants (n, m) & closes it in nonm) & closes it in non--resonating resonating ones. ones.

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