8. Anatomy and physiology of the paranasal sinuses. Clinical Examination of the. Acute and Chronic Rhinosinuitis. Flashcards
What are PARANASAL SINUSES?
Air-filled Cavities in Frontal / Ethmoid / Maxilla / Sphenoid Bones
- Lined with Mucosal Membrane and have 4 Small Openings into Nasal Cavity:
1) Maxillary Sinuses
2) Ethmoid Sinuses
3) Sphenoid Sinuses
4) Frontal Sinuses
What are MAXILLARY SINUSES?
- Located in Body of Maxilla, BEHIND the Cheek
- ABOVE the Roots of pre-molar / molar teeth
- Opens into NC via Semilunar Hiatus
- LARGEST of Paranasal Sinuses
- Capacity = 30ml
- Has BIPHASIC Growth
a. 1st Growth = First 3 Years of Life
b. 2nd Growth = Age 7 - 18
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0 BLOOD SUPPLY - Facial Artery FROM External Carotid Artery
- Infra-Orbital / Greater Palatine Artery FROM Maxillary Artery FROM the External Carotid Artery
- ## Venous Drainage via Facial Vein / Pterygoid Plexus0 INNERVATION
- Anterior / Middle Superior Alveolar Nerve FROM Infra-Orbital Nerve
- Posterior Superior Alveolar Nerve FROM Maxillary Nerve
What are ETHMOID SINUSES?
- Has Anterior / Middle / Posterior Ethmoid Sinuses
- Anterior ES = Opens into NC via Infundibulum
- Middle ES = Opens into Ethmoid Bulla
- ## Posterior ES = Opens into Superior Meatus0 BLOOD SUPPLY
- Anterior ES = Anterior Ethmoidal Artery / Vein
- ## Posterior ES = Posterior Ethmoidal Artery / Vein0 INNERVATION
- Anterior ES = Anterior Ethmoidal Nerve
- Middle ES = Orbital Branches of Pterygopalatine Ganglion
- ## Posterior ES = Posterior Ethmoidal Nerve / Orbital Branches of Pterygopalatine Ganglion0 LYMPH DRAINAGE
- Anterior ES = Submandibular LN
- Middle ES = Submandibular LN
- Posterior ES = Retropharyngeal LN
What are SPHENOID SINUSES?
- Sinuses found in Sphenoid Bone, where each open into Sphenoethmoid Recess
- Development starts at Age 4 and Completes by Age 17
- ## Drain thru SUPERIOR MEATUS via Small Ostium0 BLOOD SUPPLY
- Posterior Ethmoidal / Internal Carotid Arteries
- ## Pterygoid Venous Plexus / Cavernous Sinus0 INNERVATION
- Posterior Ethmoidal Nerve
- ## Orbital Branches of Pterygopalatine Ganglion0 LYMPH DRAINAGE = Retropharyngeal Nodes
What are FRONTAL SINUSES?
- Found in Frontal Bone and run ABOVE MEDIAL End of Eyebrow and BACK to Orbit
- Open into NC via Semilunar Hiatus
- L-Shaped Sinus, which appears later in life
- ## Drains into ANTERIOR part of MIDDLE MEATUS via Fronto Nasal Duct0 BLOOD SUPPLY
- Supra-Orbital Artery
- ## Veins connecting Supra-Orbital / Superior Ophthalmic Veins0 INNERVATION = Supra-Orbital Nerve FROM Ophthalmic Nerve
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0 LYMPH DRAINAGE = Submandibular Nodes
What is the PHYSIOLOGY of PARANASAL SINUSES?
1) DECREASING weight in front of skulls
2) INCREASING resonance of voice
3) PROVIDES BUFFER against Facial Trauma
4) INSULATING Sensitive structures like Dental Roots / Eyes from Rapid Temp fluctuations in NC
What is ACUTE RHINOSINUSITIS?
- Acute Inflammation of Membranous Lining of Sinus
- ## AKA Sinusitis0 DUE to Spread of Intranasal Inflammation / Rhinitis as Mucosa of Paranasal Sinus communicates with NC
0 SYMPTOMS
- Headache, which worsens when bending over
- Pain
- Ethmoid Sinusitis (MOST Painful) over Nose Bridge / Medial Canthus of EYE
0 DIAGNOSIS = Rhinoscopy / Nasal Endoscopy
- Revels PUS ALONG Middle Meatus
0 TREATMENT
- Conservative Tx = Decongestant Nose Drops / Nasal Spray
- Surgical Tx = Maxillary Sinus Puncture / Topic Anaesthesia of Nasal Mucosa
What is CHRONIC RHINOSINUSITIS?
- CHRONIC Inflammation of Membranous Lining of Sinus
- IMPAIRED Ventilation of the Osteomeatal Unit DUE TO, Stenosis / Obstruction
- Frequently affects MAXILLARY Sinus AND ETHMOID Cells
0 SYMPTOMS
- Pain
- Pressure
- Persistent Headaches
- Nasopharyngeal Drainage
- Obstructed Nasal Breathing
0 DIAGNOSIS = Rhinoscopy / Endoscopy
0 TREATMENT
- Decongestant Nose Drops
- Heat Therapy
- Broad-Band Antibiotics = AMOXICILLIN
