🥇 CAVIDAD NASAL 1. (1/2). ¡Explicación Fácil y Sencilla! (Huesos, Límites y Relaciones)

Introduction to the Nasal Cavity

In this video, Juan José Sánchez provides an anatomical overview of the nasal cavity. He explains that the topic will be divided into two videos, with this first part focusing on the boundaries and structures within the cavity.

Boundaries of the Nasal Cavity

• The nasal cavity is a double cavity that does not communicate with each other due to the presence of a nasal septum.

• It extends from the anterior region called the nostrils or inferior nasal openings to the posterior region known as choanae.

• Superiorly, it is related to structures such as frontal sinuses, ethmoid cells, and middle cranial fossa.

• Inferiorly, it is separated from the oral cavity by the hard palate.

• Laterally, it is related to structures like maxillary sinus, orbit, and lateral nasal wall.

Functions of the Nasal Cavity

• The nasal cavity has two primary functions:

• Olfactory function: It houses olfactory nerves responsible for carrying smell sensations.

• Respiratory function: It allows air passage towards lungs through various conduits.

Key Relationships of the Nasal Cavity

• Superior relationships include frontal sinuses, ethmoid cells, and middle cranial fossa.

• Inferior relationship includes separation from oral cavity by hard palate.

• Medial relationship includes nasopharynx separated by an orifice.

• Lateral relationships include maxillary sinus, orbit, and lateral nasal wall.

Conclusion and Channel Subscription Reminder

Juan José Sánchez concludes by reminding viewers to subscribe to his channel for more anatomical videos. He also emphasizes understanding facial bones for better comprehension of future topics.

Importance of Facial Bone Knowledge

• Understanding facial bones is crucial for comprehending nasal cavity boundaries and relationships.

• Viewers are encouraged to watch videos on anatomical landmarks of facial bones available on the channel.

The transcript does not provide any additional content after this point.

Anatomy of the Nasal Cavity

This section provides an overview of the boundaries and structures within the nasal cavity.

Boundaries of the Nasal Cavity

• The medial boundary is formed by the vomer bone and the perpendicular plate of the ethmoid bone.

• The inferior boundary is formed by the posterior part of the horizontal plate of the palatine bone.

• The lateral boundary is formed by the curved upper surface of the superior concha and the body of the sphenoid bone.

Roof and Floor of the Nasal Cavity

• The roof (superior boundary) is concave in shape, with different structures contributing to its formation, including nasal cartilages, frontal bone, cribriform plate, and body of sphenoid bone.

• The floor (inferior boundary) is relatively horizontal in an anteroposterior direction but curved laterally. It is known as the palatal vault or hard palate.

Nasal Septum

• The nasal septum forms a medial wall between both nasal cavities.

• It consists of several components:

• Anteriorly: Cartilage septum

• Posteriorly: Perpendicular plate of ethmoid bone and vomer

• Mobile portion: Septal cartilage and alar cartilages

Vomeronasal Organ

• Located at the anterior part of the nasal septum.

• Also known as Jacobson's organ.

• Plays a role in detecting pheromones in certain vertebrate species.

Structure of Nasal Cavity Roof

This section focuses on describing how different structures contribute to forming the roof (superior boundary) of the nasal cavity.

Components Contributing to Nasal Cavity Roof

• Nasal cartilages contribute to the anterior part of the roof.

• Frontal bone helps form the roof in the anterior region.

• Cribriform plate of ethmoid bone contributes to the middle part of the roof.

• Body of sphenoid bone forms the posterior part of the roof.

Structure of Nasal Cavity Floor

This section describes the structure and formation of the floor (inferior boundary) of the nasal cavity.

Formation of Nasal Cavity Floor

• The floor is relatively horizontal in an anteroposterior direction but curved laterally.

• It is formed by:

• Incisive foramen

• Horizontal plates of palatine bones

• Fusion of palatine processes of maxillary bones in the midline, forming the hard palate.

Nasal Septum and its Components

This section provides an overview of the nasal septum and its various components.

Components of Nasal Septum

• Anteriorly: Cartilage septum

• Posteriorly: Perpendicular plate of ethmoid bone and vomer

• Mobile portion: Septal cartilage and alar cartilages

Subdivision within Nasal Septum

• The perpendicular plate of ethmoid bone and vomer divide it into two parts:

• Bony part (perpendicular plate)

• Cartilaginous part (septal cartilage)

Mobile Portion - Columella or Subtabique

• Refers to a movable portion at the anterior end, consisting of skin, subcutaneous tissue, and two alar cartilages.

• Also known as columella or membranous part.

New Section

This section discusses the lateral wall of the nasal cavity and the bones that make up this wall.

Bones of the Lateral Wall

• The bones that make up the lateral wall of the nasal cavity include:

• Nasal bones or nasal septum

• Maxillary bone

• Lacrimal bone

• Superior and middle nasal conchae

• Inferior nasal concha

• Palatine bone

Structures in Relation to the Middle Meatus

• The middle meatus is located between the middle nasal concha and inferior nasal concha.

• Structures related to the middle meatus include:

• Ethmoidal cells: posterior part of ethmoidal sinuses

• Palatine canal: related to palatine bone and sphenoid sinus drainage

Structures in Relation to the Superior Meatus

• The superior meatus is located between the superior nasal concha and upper part of ethmoidal sinuses.

• Structures related to the superior meatus include:

• Frontonasal recess: where frontal sinus drains

• Anterior ethmoidal cells: drain into anterior part of ethmoidal sinuses

Structures in Relation to the Inferior Meatus

• The inferior meatus is located between the inferior nasal concha and floor of nasal cavity.

• Structures related to the inferior meatus include:

• Nasolacrimal duct: drains tears from conjunctiva into nose

New Section

This section continues discussing structures in relation to different parts of the nasal cavity.

Structures in Relation to Atrium

• The atrium is the entrance area of the nasal cavity.

• Structures related to the atrium include:

• Hiatus semilunaris: where maxillary sinus drains

• Ethmoidal bulla: contains openings of middle ethmoidal cells

Structures in Relation to Middle Meatus

• The middle meatus is located between the middle nasal concha and inferior nasal concha.

• Structures related to the middle meatus include:

• Infundibulum: where frontal sinus drains

• Frontonasal duct: connects infundibulum to frontal sinus

Structures in Relation to Inferior Meatus

• The inferior meatus is located between the inferior nasal concha and floor of nasal cavity.

• Structures related to the inferior meatus include:

• Nasolacrimal duct: drains tears from conjunctiva into nose

Timestamps are approximate and may vary slightly.

Overview of Nasal Cavity

In this section, the speaker discusses the nasal cavity and its structures, specifically focusing on the frontal sinus.

Nasal Cavity Structures

• The speaker explains that the air passes through the frontonasal duct, which is connected to the middle meatus.

• They point out the semilunar hiatus below, which continues with the infundibulum.

• This pathway eventually leads to the frontal sinus.

This was a brief overview of the nasal cavity and its connection to the frontal sinus.