Nasa Cavity and Paranasal Sinuses

Nasal Cavity

roughly cylindrical midline airway passage

Inferior

palatal process of the maxilla and horizontal portion of the palatine bone

Nasal Septum (Midline)

Has a bony portion posteriorly and fibrocartilaginous part anteriorly

Choana

Most posterior portion; boundary between the nasal cavity and nasopharynx

Choanal Atresia

Failure to open

Palate

Separation between the oral cavity and nasal cavity

Lateral Nasal Wall

• features three bulbous, bony projections known as the superior, middle; and inferior turbinates (conchae).

Lateral Nasal Wall

function to warm, moisture and filter airflow

Turbinates

Has bony projections

Meatus

spaces located beneath each turbinate

Meatus

DRAINAGE PATHWAY OF PARANASAL SINUSES

Superior Meatus

• Sphenoid sinus through the sphenoethmoidal recess.

• Posterior ethmoid sinus through the sphenoethmoidal recess.

Frontal Sinus

drains into the middle meatus via the frontal recess the maxillary sinus drains

Frontal sinus

goes to frontal recess and goes to the middle sinus

Inferior Meatus

Drains: nasolacrimal duct.

Hasner’s Valve

Nasolacrimal Duct opens into the inferior meatus via _____________, located 3-6 mm anterior to level of maxillary sinus ostium

Inferior Meatus

no sinus that drains here

Hasner’s Valve

whenever you cry, you produce mucus. That’s because the nasolacrimal duct drains to nasal cavity via inferior meatus which is call

Paranasal Sinuses

air-filled cavities that communicate with the nasal cavities.

Sphenoid Sinus

outpouching of the mucosa during embryonic life, but except the ethmoid air cells, they do not develop Into bony cavities until after birth

Maxillary Sinus

present at birth but remains very small until the second dentition, because the presence of tooth germs m the maxilla limit the extent of the sinuses.

Maxillary Sinus

borders the nasal cavity laterally, and the orbital floor separates the upper part of the sinus from the orbit.

Pterygopalatine fossa

Behind the Maxillary Sinus

Pterygopalatine Fossa

traversed by the maxillary artery along with branches of the trigeminal nerve and autonomic nervous system.

Maxillary sinus

• largest in volume, largest insize

• Located on the cheek area

Oroantral Fistula

The patient may complain hole on the upper dentition and is foul-

smelling and continuously draining pus.

Frontal Sinus

Located in the frontal bone, its floor forming the medial portion of the orbital roof.

Anterior Cranial Fossa

If you poke posterior boundary of frontal sinus, you’ll see the frontal lobe of the brain

Cellulitis

Intracranial Abscess/ Meningitis

• The infection from frontal sinus may extend to the orbital area and cause ________

• If it extends posteriorly, may cause ___________

Ethmoid Sinus

Superior and medial to the maxillary sinus

Lamina Papyracea

• orbital plate of the ethmoid bone

• forms the lateral bony wall that separates the ethmoid air cells from the orbit

Sphenoid Sinus

Clivus

1. located at the approximate center of the skull above the nasopharynx.

2. Its posterior wall is formed by

Cavernous Sinus

the internal carotid artery, and cranial nerves II-VI, and it is very closely related to the optic canal.

Lateral

meningeal layer of the dura mater running from the roof to the floor of the middle cranial fossa.

Roof

meningeal layer of the dura mater that attaches to the anterior and middle clinoid processes of the sphenoid bone.

Floor

endosteal layer of dura mater that overlies the base of the greater wing of the

sphenoid bone.

Ophthalmic veins (superior and inferior)

these enter the cavernous sinus via the superior orbital fissure.

Central vein of the retina

drains into the superior ophthalmic vein, or directly into the cavernous sinus.

Sphenoparietal sinus

empties into the anterior aspect of the cavernous sinus.

Superficial middle cerebral vein

contributes to the venous drainage of the cerebrum

Pterygoid plexus

located within the infratemporal fossa

Abducens nerve (CN VI)

Carotid plexus

Internal Carotid Artery

Travels through cavernous snus (3)

Oculomotor Nerve (CN III)

Trochlear Nerve (CN IV)

Ophthalmic (V1) and Maxillary (V2) branches of Trigeminal Nerve

Travels through lateral wall of cavernous sinus (3)

Superior Opthalmic Vein

The veins of the ace drain blood into the cavernous sinus via the

CAVERNOUS SINUS THROMBOSIS

infections of the face (particularly those involving the "danger triangle" (orbits, nasal sinuses, and superior part of the face) can cause

CN VI

Most Commonly affected in Cavernous Sinus Thrombosis

PARANASAL SINUS VOLUME

• Maxillary Sinus: 15ml

• Frontal Sinus: 4-7ml

• Ethmoid Sinus: 2-3ml

• Sphenoid Sinus: 0.5ml- 8ml

PARANASAL SINUS VOLUME

• Maxillary Sinus:

• Frontal Sinus:

• Ethmoid Sinus:

• Sphenoid Sinus:

Nasal Septum

• Quadrangular Cartilage - Septal Cartilage

• Perpendicular Plate of tie Ethmoid projects from cribriform plate to septal cartilage

Vomer

posterior and inferior to perpendicular plate

Anterio Nasal Spine

bony projection anterior to piriform aperture

External Nose

derives most of its blood supply from the facial artery

Internal Nose

receives blood from the territories of the external and internal carotid arteries

FACIAL ARTERY - ECA

Lateral surface of caudal nose (angular nasal artery > lateral nasal artery)

OPHTHALMIC ARTERY - ICA

Nasal dorsum (dorsal nasal artery)

FACIAL ARTERY

supplies the superior labial artery, which enters the nose and supplies the anterior nasal septum

Internal Maxillary

Courses within the pterygopalatine

SPHENOPALATINE ARTERY

It enters the nasal cavity through the sphenopalatine foramen

DESCENDING PALATINE ARTERY

It courses through the greater palatine canal becomes the greater palatine artery entering the nose through the incisive foramen to supply the anterior inferior septum

POSTERIOR ETHMOID ARTERY

passes through the posterior ethmoid canal into the anterior cranial fossa and divides into lateral and medial branches

OSTIOMEATAL UNIT/COMPLEX

area on the lateral nasal wall where the ostia or the paranasal sinuses

(except for the sphenoid sinus) open into the nasal cavity in a duct-like fashion.

Frontal Recess

hourglass-like shape.

UNCINATE PROCESS

thin fibrous or bony process on the lateral nasal wall

SEMILUNAR HIATUS

slit-like passage within the ostiomeatal complex

ETHMOID INFUNDIBULUM

The space between the uncinate process, ethmoid bulla, and lamina papyracea of the ethmoid bone

Epistaxis

most common otolaryngologic emergency

9

A transfusion threshold of ____ g/dL has been advocated, because this has been shown to improve outcome.

KIESSELBACH'S PLEXUS (LITTLE'S AREA)

most common site of epistaxis (90%)

Silver nitrate cautery

Mild epistaxis from Kiesselbach's area can often be controlled by selective local

cauterization of the bleeding site with silver nitrate.

double-lumen balloon catheter

introduced and inflated with water to produce local compression in the nasal cavity and nasopharynx.

Arterial hypoxia

fall of oxygen partial pressure with pulmonary dysfunction due to an impaired

nasopulmonary reflux mechanism.

Toxic shock

focal staphylococcal infection develops within 24h after nasal packing, with

generalized shock symptoms caused by bacterial toxins.

JUVENILE NASOPHARYNGEAL ANGIOFIBROMA (JNA)

• most common vascular mass in nose

• most common nasopharyngeal benign neoplasm typically

  affects adolescent males

JUVENILE NASOPHARYNGEAL ANGIOFIBROMA (JNA)

SMOOTH PURPLISH LOBULATED MASS

• Endoscopic Surgery

• Open Surgical Approaches

JUVENILE NASOPHARYNGEAL ANGIOFIBROMA (JNA) Management (2)

Allergoc Rhinitis

hypersensitivity of the nasal mucosa to foreign substances mediated through IgE antibodies.

• Recurrent episodes of wheezing

• Pruritus

• Rhinorrhea

• Nasal congestion

The classic symptoms of seasonal allergic rhinitis are (4)

Itching

symptom most suggestive of an allergic etiology and involves not only the nose

but also the palate, throat, eyes, and ears.

Rhinorrhea

usually clear and can be anterior, resulting in sniffing and nose blowing

posterior, resulting in snorting, throat clearing, and postnasal drip.

Nasal Obstruction

may be bilateral or could manifest as exaggeration of the nasal cycle with alternating unilateral obstruction.

EUSTACHIAN TUBE DYSFUNCTION

manifested as ear popping and clicking, is an occasional manifestation.

Seasonal

Perennial

Episodic

THE TRADITIONAL CLASSIFICATION OF ALLERGIC RHINITIS (3)

SEASONAL ALLERGIC RHINITIS

occur during exposure to seasonal allergens, such as ragweed, grasses, outdoor molds, and tree pollens.

PERENNIAL ALLERGIC RHINITIS

nasal symptoms for more than 2 hours per day for more than 9 months of the year, occurs when allergies develop to house dust mites, indoor molds, animal dander, and cockroaches.

EPISODIC RHINITIS

exposure to allergens not normally present in the environment, such as a cat-allergic individual who becomes symptomatic upon entering the home of relatives who have a cat.

INTERMITTENT ALLERGIC RHINITIS

refers to symptoms present for less than 4 days a week or for less than 4 consecutive weeks

PERSISTENT ALLERGIC RHINITIS

refers to symptoms present for more than 4 days a week and for more than 4 consecutive weeks, with the realization that patients usually suffer almost every day.

ALLERGIC SHINERS

periorbital cyanosis and puffiness of the eyelids result of venous stasis secondary to chronic nasal obstruction

ALLERGIC SALUTE

Oxymetazoline

Tx for Allergic Rhinitis

Nasal endoscopy

allows visualization of the middle meatus to rule out the existence of purulent discharge or small polyps that originate in the sinuses.

Allergen Extract

Used as negative control

Histamine or Codeine

Used as positive control

15

A wheal and flare reaction is seen within ___ minutes of

injection if a patient is sensitive to a specific antigen.

Avoidance

effective treatment for allergic rhinitis

H1 antihistamines

act as inverse agonists that combine with and stabilize the inactive conformation of the H1- receptor, shifting the equilibrium toward the inactive state.

Diphenhydramine

these drugs are lipophilic and have varying degrees of anticholinergic and sedating side effects

Oral H1 antihistamines

effective in controlling histamine-mediated symptoms that include sneezing, itching, rhinorrhea, and eye symptoms such as itchy and watery eyes, but these drugs are minimally effective in alleviating nasal congestion.

Azelastine

phthalazinone derivative

Olopatadine hydrochloride

Tx for Seasonal Allergic Rhintis, bitter taste

Rebound

Prolonged use leads to a progressively shorter duration

of action, until almost continuous application provides no

relief—a condition known as