PARANASAL SINUSESAnatomy, Physiology and Diseases

Maria Angelica M. GeronimoGroup 5a

PARANASAL SINUSES

• Air-filled cavities that communicate with the nasal cavities

PARANASAL SINUSESAnatomy

Maxillary SinusFrontal Sinus

Anterior Ethmoid cells

Middle Meatus

NASAL CAVITY

Posterior Ethmoid cells

Superior Meatus

NASAL CAVITY

MAXILLARY SINUS

• Medial: nasal cavity• Floor: close to the root

of the second premolar and first molar teeth

• Posterior: Pterygopalatine fossa– Traversed by the

maxillary artery, branches of the CN V and ANS

ETHMOID AIR CELLS

• Labyrinthine system of small, pneumatized sinus cavities

• Posterior: close to CN II• Lamina papyracea – Orbital plate– Forms the lateral bony

wall that separates it from the orbit

SPHENOID SINUS

• Center of the skull above the nasopharynx

• Clivus - forms the posterior wall

• Superior: sella turcica + pituitary, and anterior and middle cranial fossae

• Lateral: cavernous sinus, ICA and CN II-VI

• Closely related to CN II

FRONTAL SINUS

• Floor: forms the medial portion of the orbital roof

• Anterior: anterior cranial fossa

PARANASAL SINUSESPhysiology

Functions

• Humidification• Vocal resonance• Mucus production• Increased olfactory area• Absorbs shock to the head• Regulation of intranasal pressure

PARANASAL SINUSESDiseases

Sinus Inflammation

Acute Chronic

MAXILLARY SINUSITISPredisposing factors Mild URTI

Nasal allergiesForeign bodiesDeviated nasal septum

Symptoms Fever, vague headache relieved by analgesics, malaiseFullness of the face, pain in the teeth esp. upon going up and down the stairsDull, throbbing cheek pain

Signs Tenderness to pressure and percussionFoul, mucopurulent secretionsDecreased transilluminationWater’s view- mucosal thickening and opacification of the maxillary sinuses

Organism Streptococcus pneumoniae, H. Influenzae, anaerobes, Branhamella Catarrhalis

Treatment Antibiotics, decogestants, analgesics

ETHMOID SINUSITISPrevalence Children: orbital cellulitis

Adults: accompanies maxillary sinusitis

Symptoms Pain and tenderness between the eyes and over the bridge of the noseThick nasal secretionsNasal obstruction

Treatment Antibiotics, nasal decongestants, analgesics, nasal sprays

FRONTAL SINUSITISPrevalence Associated with anterior ethmoditis

Predominantly in adults

Symptoms Pain is above the eyebrows usually in the AM, worse at midday, gradually lessens at the end of the dayForehead may be tender to touch and may have supra orbital swelling

Treatment Antibiotics, decongestants, vasoconstrictor nasal sprays

SPHENOID SINUSITISPrevalence Associated with other sinusitis

Not very common

Symptoms Headache directed to the vertex of the skull

Treatment Antibiotics, decongestants, vasoconstrictor nasal sprays

PARANASAL SINUSESComplications

Orbital Complications

Orbital Cellulitis

Abscess

Subperiosteal abscess

Orbital abscess

Cavernous Sinus Thrombosis

MUCOCOELE

• Mucus containing cyst found in the sinuses

• Frequently seen in the maxillary sinuses (mucus retention cysts)

• Ethmoids or frontal sinuses: swelling in the forehead

• Sphenoids sinus: diplopia or impaired vision

PYOCOELE

• Similar to a mucocoele but contains pus• Treatment: surgical removal and re-

establishment of a good drainage

ACUTE MENINGITIS

• Infections may spread through venous channels or directly from neighboring sinuses such as posterior wall of the frontal sinus

• Fever, chills, nausea, vomiting, signs of meningeal irritation

DURAL ABSCESS

• Collection of pus between dura and internal table of the skull usually seen in frontal sinusitis

• Intractable headache, spiking fever, may have signs of meningeal irritation

• Increased ICP

BRAIN ABSCESS

• Occurs through directly extending thrombophlebitis

• Brain may be contaminated at the peak of a severe suppurative sinusitis

• Chills and fever, lack of appetite, weight loss, nausea and vomiting

• Treatment: Massive IV antibiotics, surgical drainage

OSTEOMYELITIS

• Commonly seen in frontal sinusitis• Erosion of the frontal bone• Localized forehead pain, fever, chills, swelling

over brow area• Radiographs: “moth-eaten” appearance of the

margins of the sinuses