B24 - Nasal cavity, blood supply and innervation

Question 1

Structures to mention in cavum nasi

Answer 1

• Nares (Nostrils)
  
  • Diverticulum nasi (eq) (Cutaneous blind sac extending from the dorsal angle of the nostril to the caudal end of the incisura nasoincisiva)
• Choanae (Openings between the nasal cavities and the nasopharynx)
• Septum nasi (Separating the right and left nasal cavities)
  
  • Cartilago septi nasi
• Organum vomeronasale (On the floor of the nasal cavity next to the septum)
• Vestibulum nasi (Rostral part of the nasal cavity)
• Limen nasi (Boundary between vestibulum nasi and nasal cavity proper)
• Ostium nasolacrimale (Orifice of the nasolacrimal duct)
• Concha nasalis dorsalis (Attached to os ethmoidale and os nasale)
• Concha nasalis media (Between caudal ends of dorsal and ventral choanae and choanae ethmoidalis)
• Conchae ethmoidales (From the labyrinth in the caudal end of the nasal cavity)
• Concha nasalis ventralis (Attached to maxilla)
• Gll. olfactoriae (In lamina propria of the regio olfactoria)
• Gll. nasales (In lamina propria of the regio olfactoria)
• Gl. nasalis lateralis (Ø bo) (In sinus maxilarris (car: recessus) or apertura nasomaxillaris)
• Meatus nasi dorsalis (Passage between choana nasalis dorsalis → dorsal wall of the nasal cavity)
• Meatus nasi medius (Between choana nasalis dorsalis → choana nasalis ventralis)
• Meatus nasi ventralis (Between choana nasalis ventralis → floor of the nasal cavity)
• Meatus nasi communis (Sagittal passage along septum nasi)
• Meatus ethmoidales (Passage between the choana ethmoidales)
• Nasal cavity extends from the nostrils → cribiform plate of os ethmoidale
• Divided by septum nasi into right and left sides

Question 2

List the interspecies structures in cavum nasi

Answer 2

• Nares
  
  • Diverticulum nasi (eq) (skin with fine hairs extends into the nasal cavity
• Gl. nasalis lateralis (ø bo)

Question 3

Role of the nasal cavity

Answer 3

• First part of the respiratory system
• Heat the air
• Clean and moist the air

Question 4

What is the floor of the nasal cavity composed of?

Answer 4

• Floor of the nasal cavity = roof of the oral cavity
• Floor is composed of:
  
  • Os incisive
  • Proc. palatinus of os maxilla
  • Os palatinum
• Covered by nasal mucosae dorsally

Question 5

What divides the nasal cavity from the cranial cavity?

Answer 5

• Os ethmoidale
• Nasal part of os frontale
• Rostrum of presphenoid

Question 6

What is the middle portion of the nasal cavity composed of?

Answer 6

• Concha nasalis dorsalis
• Concha nasalis media
• Concha nasalis ventralis

Riktig???

Question 7

What is the caudal portion of the nasal cavity composed of?

Answer 7

• Conchae ethmoidales
  
  • ​From labyrinth → caudal end of the nasal cavity
  • Olfaction
• Lamina cribosa

Question 8

Nasal and ethmodal conchae

Answer 8

• Thin osseus scrolls
• Origin: basal lamella from the lateral wall of the nasal cavity
• Lamella projects medially and is continued by spiral lamalla
• Spiral lamellae enclose airfilled recesses which communicate with meatus nasalis
• If the free border of a spiral lamina unites wiht its basal lamella or with an adjacent nasal bone → conchal sinus
• Concha nasalis dorsalis:
  
  • ​From cribiform plate → vestibulum nasalis
    
    • ​Attached to crista ethmoidalis of os nasale
• Concha nasalis ventralis:
  
  • ​Arises from c**rista conchalis of maxilla
• Choana nasalis dorsalis et ventralis:
  
  • ​Project from the lateral wall
  • Divide the nasal cavity into 3:
    
    • Meatus nasi dorsalis
    • Meatus nasi medius
    • Meatus nasi ventralis
• Concha nasalis media:
  
  • ​Between caudal ends of the:
    
    • Concha nasalis dorsalis
    • Concha nasalis ventralis
    • Concha ethmoidales

Question 9

Meatus

Answer 9

• Choana nasalis dorsalis et ventralis
  
  • ​Project from the lateral wall
  • Divide the nasal cavity into 3:
    
    • Meatus nasi dorsalis
      
      • ​Between roof of nasal cavity → conchae dorsalis
      • Leads into caudal part of the nose
    • Meatus nasi medius
      
      • ​Between conchae dorsalis → conchae ventrlalis
      • Leads into caudal part of the nos
    • Meatus nasi ventralis
      
      • ​Between conchae ventrlalis → floor of nasal cavity
      • Leads into nasopharynx
      • Most of the air passes through this meatus, largest
• Meatus nasalis communis
  
  • ​Between septum nasi → conchae
  • Extends from the roof of the nasal cavity → floor of nasal cavity
  • Sagittal passage along septum nasi
• Meatus ethmoidales
  
  • ​Passage between ethmoidal cochae

Question 10

Draw the nasal cavity

Answer 10

Question 11

Ductus incisivus

Answer 11

• Paired tube in the floor of the nasal cavity
• Connects the nasal cavity with the oral cavity
• Nasal opening: in meatus ventralis
• Oral opening: on the papilla incisiva
  
  • ​Eq: does not open into the nasal cavity (under oral epithelium)

Question 12

Organum vomeronasale

Answer 12

• Pair of blind ducts
• Location: floor of nasal cavity, each side of septum nasi
• Supported by thin-walled cartilaginous sleeves and vomer
• Special olfactory function

Question 13

Ethmoturbitates

Answer 13

• Curled structures
• Delicate scroll-like bones in the nasal cavity
• Origin: os ethmoidale
• Ectoturbinates:
  
  • ​Smaller
• Endoturbinates:
  
  • ​Larger
  • Nearly reach septum nasi
  • First 2 is named:
    
    • Concha nasalis dorsalis
    • Concha nasalis media
• Maxilloturbinate = concha nasalis ventralis
  
  • ​Only tubrinate rising from maxilla

Question 14

List the glands of the nasal cavity

Answer 14

• Gll. olfactoriae
  
  • ​Sereomucous
• Gll nasales
  
  • ​Mixed
• Gl. nasalis lateralis (ø bo)
  
  • Serous
  • In sinus maxillaris (car: recessus maxillaris)
  • Duct opens inside nostril

Question 15

Blood supply

Answer 15

• A. maxillaris
  
  • ​A. palatina descendens
    
    • ​A. sphenopalatina
      
      • ​A. nasalis caudales
      • ​A. nasalis laterales
      • ​A. nasalis septales
    • A. palatine major (hard palate & meatus nasalis ventralis)

Question 16

Innervation

Answer 16

• N. olfactorius (I) (→ lamina cribosa)
  
  • N. vomeronasalis (starts in organum vomeronasale → ends in bulbus olfactorius accessorius)

ELLER???:

• N. opthalmichi (V₁)
  
  • ​N. nasociliaris
    
    • ​N. ethmoidalis → cribiform plate → rr. lateralis & rr. medialis to mucosa
• N. maxillaris (V₂)
  
  • N. palatina majoris (→ floor of nasal vestibulum?)
  • N. nasalis caudalis (→ mucosa of ventral cavity, maxillary sinus & palate)