Download aortic arches

EMBRYOLOGY OF THE
PHARYNGEAL APPARATUS,
TONGUE &THYROID GLAND
STEVEN J. ZEHREN, PH.D.
PHARYNGEAL
APPARATUS
Site of midbrain
Pharyngeal
(branchial) arches
Lens placode
Somites
Max.
prom.
1
Nasal placode
2
3 4
Mand.
prom.
A
Stomodeum
Heart
PHARYNGEAL ARCHES FORM DURING 4TH WEEK.
ECTODERMAL
GROOVES SEPARATE ARCHES ON OUTSIDE.
Slide
10.1
STOMODEUM & OROPHARYNGEAL MEMBRANE
Endoderm
of pharynx
Oropharyngeal
membrane
Ectoderm
Stomodeum
(primitive oral cavity)
Frontonasal
prominence
Eye
Maxillary prominence
Entrance to stomodeum
Mandibular prominence
Second pharyngeal arch
Umbilical vein
Third pharyngeal arch
Fourth pharyngeal arch
Entrance to
intraembryonic coelom
Spinal cord
Slide 10.31
SCANNING EM OF EMBRYO (5TH WEEK)
1st pharyngeal pouch
Midbrain
Aortic arches
(1st to 4th)
Esophagus
Level of
section C
Lung bud
Dorsal aorta
Esophagus
B
Thyroid diverticulum
Heart
(primordium of thyroid gland)
Truncus arteriosus (common
arterial trunk from heart)
Germ Layer Derivatives
Mesoderm
Endoderm
Ectoderm
ENDODERMAL
PHARYNGEAL POUCHES SEPARATE ARCHES ON INSIDE
Slide
10.2
Mandibular (1st) arch
1st arch
(Meckel)
1st pharyngeal
(branchial) membrane
Cartilages
2nd arch
(Reichert)
Hyoid (2nd) arch
Nerve
2nd pharyngeal pouch
Muscle
3rd aortic arch
C
3rd pharyngeal pouch
Mesodermal core of 4th arch
Germ Layer Derivatives
Ectoderm
Slide 10.3
Endoderm
Mesoderm
COMPONENTS OF A PHARYNGEAL ARCH
PHARYNGEL ARCH CARTILAGES: DERIVATIVES
ZYGOMATIC
MAXILLA
SQUAMOUS
TEMPORAL
MANDIBLE
MEMBRANE BONES OF ARCH 1
PHARYNGEAL ARCH MUSCLES: DERIVATIVES
(Arch 2)
(Arches 4 &6)
(Arch 1)
(Arch 1)
(Arch 3)
PHARYNGEAL ARCH NERVES
3rd, 4th, and 6th aortic arches
Spinal cord
Midbrain
Pulmonary artery
Dorsal aorta
Aortic sac
Yolk stalk
Yolk sac
C
PHARYNGEAL ARCH ARTERIES (AORTIC ARCHES)
Slide 14.56
3rd aortic arch
4th aortic arch
6th aortic arch
Truncus arteriosus
Aortic sac
Dorsal aortae
Left dorsal aorta
Left dorsal aorta
External
carotid artery
Internal
carotid artery
Right
3
3
4
5 6
Aortic arches
Truncus arteriosus
(partly divided
aortic and pulmonary
arteries)
Aortic sac
4
5
6
Right
subclavian artery
Aortic sac
Ductus arteriosus
Left dorsal aorta
Pulmonary arteries
Left subclavian artery
7th intersegmental artery
A
6 WKS
B
7 WKS
TRANSFORMATION OF AORTIC ARCHES (VENTRAL VIEW)
Slide 14.57
3rd aortic arch
4th aortic arch
6th aortic arch
Truncus arteriosus
Aortic sac
Dorsal aortae
Internal carotid arteries
Left common
carotid artery
External carotid arteries
Right
Brachiocephalic artery
Left
subclavian artery
Subclavian arteries
Arch of aorta
Ascending
aorta
Right pulmonary artery
Ligamentum
arteriosum
Ductus arteriosus
Left pulmonary
artery
Ascending aorta
Descending aorta
C
Pulmonary trunk
8 WKS
D
6 MO. INFANT
TRANSFORMATION OF AORTIC ARCHES (VENTRAL VIEW)
Slide 14.58
PHARYNGEAL POUCHES, GROOVES & MEMBRANES
Opercular
flap
A
B
PHARYNGEAL POUCHES, GROOVES & MEMBRANES
Foramen cecum of tongue
Tongue
Tract of
thyroglossal duct
Auditory tube
(pharyngotympanic tube)
and tympanic cavity (pouch I)
Tonsillar sinus and
surface epithelium
of palatine tonsil
(pouch II)
Larynx
Pouch IV
Ultimobranchial
body (pouch IV)
Pouch III
Parathyroid
glands
Thyroid gland
Thymus (pouch III)
20
FETUS SHOWING DERIVATIVES OF PHARYNGEAL POUCHES
Slide WEEK
10.13
Hyoid bone
Undescended
parathyroid gland
Persistent
thyroglossal duct
Accessory
thymic tissue
Thyroid
cartilage
Thyroid gland
Trachea
Manubrium
of sternum
Retrosternal
thymus
Superior
parathyroid
glands
Persistent cord
of thymic tissue
Ectopic inferior
parathyroid gland
Body of sternum
Slide 10.19
CONGENITAL
ANOMALIES OF THYROID, THYMUS & PARATHYROID GLANDS
LATERAL CERVICAL CYSTS
(REMNANTS OF CERVICAL SINUS)
Epicardial ridge
(SCM develops in it)
A
B
C
LATERAL CERVICAL
CYST. NOTE ITS
POSITION ANTERIOR
TO SCM MUSCLE.
Sternocleidomastoid
muscle
Swelling formed by
branchial cyst
Tendon of
sternocleidomastoid
muscle
Slide 10.16
TONGUE
Distal tongue bud
Arches:
Migration of third
arch mesoderm
1
Median tongue bud
2
Hypobranchial
eminence
Foramen cecum
of tongue
3
4
Copula
Hypobranchial
eminence
A
Esophagus
Rima glottidis
(opening to vocal
apparatus)
B
Laryngotracheal groove
5 WKS
Median sulcus
4 WKS
Oral part
of tongue
Circumvallate
papillae
Terminal sulcus
Pharyngeal
part of tongue
Foramen cecum
of tongue
C
Epiglottis
ADULT
Arch Derivatives of Tongue
1st pharyngeal arch
(CN V-mandibular division)
3rd pharyngeal arch
(CN IX-glossopharyngeal)
Slide 10.26
2nd pharyngeal arch
(CN VII-chorda tympani)
4th pharyngeal arch
(CN X-vagus)
DEVELOPMENT OF TONGUE
Temporalis
Orbicularis oculi
Frontalis
Auricularis
Occipital myotomes
Buccinator
Occipitalis
Stylohyoid
Orbicularis oris
Stylopharyngeus
Masseter
Anterior and
posterior bellies
of digastric muscle
Mylohyoid
B
A
Pharyngeal
muscles
Sternocleidomastoid
First arch
muscles
Second arch
muscles
Third arch
muscles
Platysma
Clavicle
Fourth and sixth
arch muscles
ALL TONGUE MUSCLES (EXCEPT PALATOGLOSSUS)
DEVELOP FROM OCCIPITAL MYOTOMES
Slide 10.9
THYROID GLAND
Pharyngeal pouches
Primordial
pharynx
Thyroid
diverticulum
4
WKS
A
Esophagus
Oropharyngeal
membrane
Heart
Pharyngeal
arches
Laryngotracheal
diverticulum
Foramen cecum of tongue
Tongue
Thyroglossal duct
Thyroid
diverticulum
5
WKS
Esophagus
B
Former site of
oropharyngeal
membrane
Slide 10.20
Stomodeum
Developing
hyoid bone
DEVELOPMENT OF THYROID GLAND (EARLY)
Foramen cecum
Thyroglossal duct
Site of atrophy
of duct
C
Trachea
6 WKS
Thyroid gland
Hyoid bone
Tongue
Hard palate
Soft palate
Foramen cecum
of tongue
Former tract of
thyroglossal duct
Hyoid bone
Pyramidal lobe
of thyroid gland
ADULT
Larynx
Thyroid gland
D
Slide 10.21
DEVELOPMENT OF THYROID GLAND (LATER)
Foramen cecum
of tongue
Lingual
thyroglossal
duct cyst
Hyoid bone
Hyoid bone
Thyroid cartilage
Thyroglossal
duct cyst
A
Opening of thyroglossal duct sinus
Thyroid gland
B
Cervical thyroglossal duct cyst
THYROGLOSSAL DUCT CYSTS AND FISTULA (SINUS)
NOTE MIDLINE POSITION OF CYSTS
Slide 10.22
END OF LECTURE