Clinical Anatomy - Nasal Cavity and Sinuses

Summary

This video delves into the clinical anatomy of the nasal cavity, highlighting the sinuses. It explains the nasal cavity's structure, including the hard and soft palates, and the pharynx's three parts. Key sinuses like the frontal and sphenoid are discussed, along with the eustachian tube's connection to the ear. The video also covers the turbinates' role in warming and moistening air, and the olfactory segment's function in smell. It concludes with potential sinusitis complications, such as infection spreading to the eye or brain.

Takeaways

• 👃 The nasal cavity is bordered by the palate, which includes a hard bony palate anteriorly and a soft palate posteriorly.
• 🗣️ The pharynx, or throat, is divided into three parts: the nasal pharynx, oral pharynx, and laryngopharynx.
• 🧠 The brain sits in the cranial cavity, with a small hole in the skull leading to the frontal sinus.
• 🕳️ The sphenoid sinus is located posterior and superior to the nasal cavity.
• 👂 The eustachian tube connects the middle ear to the nasal cavity, allowing for potential ear infections from upper respiratory infections.
• 🌬️ Turbinates, or nasal conchae, warm and moisturize the air passing through the nose.
• 💧 The nasal meatus is where sinuses drain, indicating a connection between the sinuses and the nasal cavity.
• 🍃 The nasal cavity has a respiratory segment for air exchange and an olfactory segment for smell, lined with specialized cells.
• 🧠 The olfactory nerve, cranial nerve number one, carries smell signals from the olfactory segment to the brain.
• 🏔️ The sella turcica is the pituitary fossa where the pituitary gland is encased.
• 🤧 Rhinitis, or inflammation of the nasal mucosa, can lead to sinusitis, inflammation of the sinuses.
• 🔥 Complications of sinusitis can include blindness, optic neuritis, osteomyelitis, meningitis, and brain abscesses, although these are rare.

Q & A

What are the primary structures bordering the nasal cavity?

The nasal cavity is bordered by the palate, which consists of a hard bony palate anteriorly and a soft palate posteriorly, the oral cavity, the pharynx, and the nasal pharynx.

What is the function of the epiglottis?

The epiglottis acts as a gateway to the trachea, connecting the lungs, and closes during swallowing to prevent food from entering the trachea.

What is the clinical significance of the Eustachian tube?

The Eustachian tube connects the middle ear to the nasal cavity, allowing for equalization of air pressure. An upper respiratory tract infection can travel through this tube and cause a middle ear infection.

What are the turbinates and their function?

The turbinates, also known as nasal conchae, are structures within the nasal cavity that help warm and moisturize the air as it passes through the nose.

How do the sinuses drain into the nasal cavity?

The sinuses drain into the nasal cavity through the nasal meati. For example, the sphenoid sinus drains into the superior meatus, and the frontal sinus drains into the middle meatus.

What is the olfactory segment of the nasal cavity responsible for?

The olfactory segment is responsible for the sense of smell. It is lined with pseudostratified columnar epithelium containing receptors for smell.

What is the sella turcica and its relation to the pituitary gland?

The sella turcica, or 'Turkish saddle', is the pituitary fossa where the pituitary gland is located. The gland is encased by the sella turcica but does not sit directly on it.

What is rhinitis and how can it lead to sinusitis?

Rhinitis is the inflammation of the mucosal membranes in the nose. Since the nose and sinuses are connected, rhinitis can spread to the sinuses, causing sinusitis.

What are the potential complications of sinusitis?

Complications of sinusitis can include the spread of infection to the eye, causing blindness or optic neuritis, and in severe cases, osteomyelitis of the frontal sinus or meningitis.

How does a coronal section of the nasal cavity provide a different view of the sinuses?

A coronal section of the nasal cavity provides a view from the front, showing the relationship between the nasal cavity, sinuses, and other structures such as the orbit and maxillary sinus.

What is the difference between rhinitis and sinusitis?

Rhinitis is inflammation of the nasal mucosal membranes, while sinusitis is inflammation of the sinuses. Rhinitis can lead to sinusitis due to the connected nature of the nasal and sinus cavities.