Nasal Cavity and Paranasal Sinuses

Question 1

Name the bones that form the roof of the nasal cavity?

Answer 1

1. nasal
2. frontal
3. ethmoid (cribriform plate)
4. sphenoid (body)
   > Cribriform plate transmits olfactory nerves

Question 2

Name the bones that make up the floor of the nasal cavity?

Answer 2

1. palatine processes of maxillary bones
2. horizontal plate of palatine bone
   > Contains incisive foramen – transmits nasopalatine nerve & sphenopalatine artery

Question 3

Name the bones that make up the medial wall (nasal septum) of the nasal cavity?

Answer 3

1. septal cartilage
2. peripendicular plate of ethmoid bone
3. vomer
4. Processes of palatine, maxillary, frontal, sphenoid and nasal bones

Question 4

Name the bones that make up the lateral wall of the nasal cavity?

Answer 4

1. nasal bone
2. frontal process & nasal surface of maxilla
3. lacrimal bone
4. peripendicular plate of palatine bone
5. medial pterygoid plate of sphenoid bone
6. Also formed by superior & inferior concha of ethmoid bone

Question 5

Name and describe the structures and openings of the lateral wall?

Answer 5

1. Sphenoethmoidal recess
   – opening of sphenoid sinus
2. Superior meatus
   – opening of posterior ethmoidal air cells
3. Middle meatus
   – opening of frontal sinuses into infundibulum
   – opening of middle ethmoidal sinuses into ethmoidal bulla
   – openings of anterior ethmoidal air cells
   – maxillary sinus in the hiatus semilunaris
4. Inferior meatus
   – opening of nasolacrimal duct.
5. Sphenopalatine foramen
   – opening of the pterygopalatine fossa
   > Transmits the sphenopalatineartery and nasopalatine nerve

Question 6

What are the subdivisions of the nasal cavity?

Answer 6

1. vestibule
2. respiratory region
3. olfactory region

Question 7

Describe the vestibule of the nasal cavity?

Answer 7

• Dilated part inside the nostril
• Bound by alar plate
• Lined by skin and hairs

Question 8

Describe the respiratory region of the nasal cavity?

Answer 8

• consists of lower third of nasal cavity
• Warms, moistens & filters air with mucous membrane

Question 9

Describe the olfactory region of the nasal cavity?

Answer 9

• Consists superior nasal concha and upper third of nasal septum
• Innervated by olfactory nerves
  > convey sense of smell to olfactory bulb through cribriform plate of ethmoid bone

Question 10

Describe the blood supply to the nasal cavity?

Answer 10

1. Ophthalmic artery through – anterior & posterior branches of ethmoidal arteries on lateral wall.
2. Posterior lateral nasal & posterior septal branches of sphenopalatine artery of maxillary artery
3. Facial artery – through septal branch of superior labial artery & nasal branch

Question 11

Describe the venous drainage of the nasal cavity?

Answer 11

Submucosal plexus of veins
- warms air
- drains the blood supplying the nose
- follows arteries
1. Sphenopalatone vein
> pterygoid plexus
> follow maxillary artery
2. Ophthalmic vein
> cavernous sinus
> follow ophthalmic artery
3. Facial vein
> jugular vein
> follow facial artery

Question 12

Describe the lymphatic drainage of the nasal cavity?

Answer 12

Submandibular nodes
Retropharyngeal nodes
Deep cervical nodes then into jugular trunks

Question 13

Describe the innervation of the nasal cavity?

Answer 13

Olfactory nerve
Opthalmic nerve; maxillary nerve via pterygopalatine ganglion; infrorbital nerve

Question 14

Name the paranasal sinuses?

Answer 14

Ethmoidal sinus
Frontal
Maxillary
Sphenoidal sinuses
> All open onto meatuses of lateral nasal wall or into sphenoethmoid recess

Question 15

Describe the ethmoidal sinuses?

Answer 15

Have ethmoidal air cells within ethmoidal labyrinth between orbit & nasal cavity

Question 16

Ethmoidal sinuses can be divided into?

Answer 16

1. Posterior ethmoidal air cells - drain into superior nasal meatus
2. Middle ethmoidal air cells - drain into summit of ethmoidal bulla of middle nasal meatus
3. Anterior ethmoidal air cells - drain into a curved fissure hiatus semilunaris of middle nasal meatus

Question 17

Describe the frontal sinuses?

Answer 17

Lie in the frontal bone
Open into hiatus semilunaris of middle nasal meatus through frontal nasal duct (infundibulum)
Innervated by supraorbital branch of opthalmic nerve

Question 17

Describe the maxillary sinuses?

Answer 17

Largest & may be present at birth
Lie in maxillary bone lateral to nasal cavity & inferior to floor of orbit.
Open into posterior aspect of hiatus semilunaris of middle nasal meatus

Question 18

Describe the sphenoidal sinus?

Answer 18

Lies in the sphenoid bone
Opens into sphenoethmoidal recess of nasal cavity
Innervated by maxillary nerve
Pituitary gland lies above sinus
Can be surgically reached through transsphenoidal approach

Question 19

What is a sneeze?

Answer 19

Involuntary expulsion of air through mouth & nose.
- Reflex carried by branches of maxillary nerve

Question 20

What is epistaxis?

Answer 20

nose bleed from rupture of blood nasal vessels like sphenopalatine artery

Question 21

What is maxillary sinusitis?
Consequence?

Answer 21

Infections can spread from the sinus to the upper teeth causing toothache

Question 22

What is a nasal polyp?

Answer 22

Inflammatory polyp from sinuses can project into nasal cavity and may fill nasopharynx

Question 23

What is a rhinoplasty?

Answer 23

Type of plastic surgery that changes shape and size of nose

Question 24

Describe the openings of the nasal cavity?

Answer 24

Open on face through nostrils or nares
Open posteriorly to nasopharynx through choanae

Question 25

What is the vestibule of the nasal cavity?

Answer 25

dilation inside aperture of each nostril
• Lined by skin with hairs, sebaceous & sweat glands