Post on 07-May-2015
HEAD AND NECKANATOMY & CLINICAL CONDITIONS
Dr S.Bola
CT1 ENT
Common exam questions• Neck triangles• Lymph node distribution• Blood supply• Neurology• Emergency airway management• How to examine a Thyroid and Parotid• Facial #• Sinuses• Headache distribution
Skeletal
Skull
Skull
STRAP MUSCLES
Neck Triangles• Anterior
• Posterior
Neck Triangles
What’s in the Anterior Triangle?
What’s in the Anterior triangle?• Strap muscles: 3 further Triangles• Common carotid artery bifurcates within the triangle
into the external and internal carotid arteries. • The internal jugular vein also can be found within this
area. It drains blood from the head and neck.
• Facial [VII], Glossopharyngeal [IX], vagus [X],• Accessory [XI], and Hypoglossal [XII] nerves.• Lymph nodes • Facial artery and vein (Submandibular traingle)• Thyroid and Parathyroids
-Some angry lady figured out PMS
-Some Ancient Lovers Find Old Positions More Stimulating
-Some Anatomists Like Fornicating, Others Prefer S & M
Facial nerve
• To• Zanzibar• By• Motor• Car
What’s in the posterior triangle?
What’s in the posterior triangle?• Omohyoid muscle- The inferior belly crosses the
posterior triangle
• Scalene muscles
• Subclavian artery-between anterior and middle scalenes, Crosses 1st rib=__________
• CVP lines: External jugular vein which empties into Subclavian vein.
Nerves in Posterior triangle• The accessory nerve (XI), descends down the neck. After
innervating the sternocleidomastoid muscle, it enters the posterior triangle. Lies relatively superficially in the posterior triangle, and is at danger of injury.
• The cervical plexus forms within the muscles of the floor of the posterior triangle. A major branch of this plexus is the phrenic nerve, which arises from the anterior divisions of spinal nerves C3-C5. It descends down the neck, within the prevertebral fascia, to innervate the diaphragm.
• The trunks of the brachial plexus also cross the floor of the posterior triangle.
Neck Layers
Neck layers• Investing Layer• Most superficial of the deep cervical fascial layers. • Surrounds all the structures in the neck. • When it meets the trapezius and sternocleidomastoid
muscles, it splits into two to completely invest the muscle.
Investing layer
Neck layers• Pretracheal Layer• It envelops the trachea, oesophagus, thyroid gland,
and the infrahyoid muscles, running from the hyoid bone down to the superior thorax, where it fuses with the pericardium.
• This layer of fascia can be functionally split into two parts:
-Visceral part – encloses the thyroid gland, trachea and oesophagus.
-Muscular part – encloses the infrahyoid muscles.
Pretracheal layer
Neck layers• Prevertebral Layer
• Surrounds the vertebral column and its associated muscles (scalence, pre-vertebral, and deep muscles of the back).
• In the inferior region of the neck, the fascia surrounds the brachial plexus and subclavian artery, and here it is known as the axillary sheath.
Prevertebral Layer
What’s in the carotid sheath?
Neck compartments
• Carotid sheaths
1. Common carotid artery (bifurcates within the carotid sheath into the external and internal carotid arteries)
2. Internal jugular vein
3. Vagus nerve
• Cervical lymph nodes
• Column that descends from the base of the skull to the thorax. This represents a pathway for the spread of infection, and it clinically very important.
Infection• Clinical Relevance: Spread of Infections
• A superficial skin abscess is prevented from spreading further into the neck by the investing layer of fascia.
Problem areas• 1. Erosion through the prevertebral fascia and drainage
into the retropharyngeal space can cause extension into the thorax +/-affect pericardium.
• 2. Between the investing fascia and pretracheal fascia - This can spread inferiorly into the chest, causing infection anterior to the pericardium.
Sinuses
Sinuses• Air filled extensions of the respiratory part of the nasal
cavity.
• There are four paired sinuses, named according to the bone they are located in; maxillary, frontal, sphenoid and ethmoid.
• Contribute to the humidifying of the inspired air. They also reduce the weight of the skull.
• As they are outgrowths of the nasal cavity, they all drain back into it.
Sinuses• Frontal Sinuses: Drain into the nasal cavity via the frontonasal duct.
• Sphenoid Sinuses: Drain out onto the roof of the nasal cavity. This relations of this sinus are of clinical importance – the pituitary gland can be surgically accessed via passing through the nasal roof, into the sphenoid sinus and through the sphenoid bone.
• Ethmoidal Sinuses: Empty into nasal cavity at different places
• Maxillary Sinuses: The largest. Located laterally and slightly inferiorly to the nasal cavities. It drains into the nasal cavity underneath the frontal sinus opening. This is a potential pathway for spread of infection – fluid draining from the frontal sinus can enter the maxillary sinus.
Clinical Relevance: Sinusitis
• Sinusitis
As the paranasal sinuses are continuous with the nasal cavity, an upper respiratory tract infection can spread to the sinuses. Infection of the sinuses causes inflammation (particularly pain and swelling) of the mucosa.
• Toothache.
The maxillary nerve supplies both the maxillary sinus and maxillary teeth, and so inflammation of that sinus can present with
Lymph nodes
Clinical Relevance
Facial muscles
Exam: What is this lump?• History-Slow/Fast/Pain/Associated red flags
-Smoking
-Hoarseness of voice
-Weight loss
-Family history
-Other primary cancer of head and neck
• Examination
-Fixed? Mobile?
-Punctum?
-Discharge?
-Red/Yellow/Black
-Position-gland, LN, BCC
-Inside mouth
-Neurology: Palsy/Parasthesia/Weakness
Midline lump
Thyroid
Thyroid swelling• A goitre is a swelling of the neck or larynx resulting from
enlargement of the thyroid gland, associated with a thyroid gland that is functioning properly or not.
• Thyroid function may be normal (nontoxic goiter), overactive (toxic goiter), or underactive (hypothyroid).
• Why operate?
Lumps in the anterior triangle
• Lymphadenopathy• Salivary gland pathology (stone, tumour, infection)• Branchial cyst• Laryngocoele• Parotid gland swelling • Carotid body tumour/ Carotid aneurysm
Parotid SwellingsUNILATERAL vs BILATERAL:
Main• Mumps• Parotitis• Sialectasis - especially if related to eating• Sjogren's syndrome• Tumour infiltration
Systemic disease:• Sarcoidosis• Tuberculosis• Alcoholism• Malnutrition
Drugs:• Thiouracil• Isoprenaline• High oestrogen contraceptive pills
Lumps in the posterior triangle
• Lymphadenopathy• Cervical rib• Pharyngeal pouch• Cystic hygroma (usually on the left)
Investigating a lump• History• Examination
• Decide on urgency (2WW)• Blood tests:
Imaging• FNA/Biopsy –Clinic or Theatre• Cervical/Chest Xrays• CT or MRI• ?PET
Chest Xray
Spot Diagnosis
What’s the diagnosis• Sjogrens• Normal WCC• CRP 10
-Investigations?
-Management?
Spot diagnosis
Spot the diagnosis
Enlarged lymph nodes
• Are you concerned?
More lymph nodes
What operation has been done?
Spot the diagnosis
Hepatojugular reflux. • External Jugular Vein Distention:
This is the result of elevated central venous pressure (CVP).
In practice the EJV is not as reliable in determining CVP as the internal jugular vein
Why?
Branchial Cyst
• Congenital• Failure obliteration of
second branchial cleft in embryo
• Anterior border of SCM
Spot diagnosis
Cystic hygroma• Congenital multiloculated
lymphatic lesion that can arise anywhere, but classically found in the left posterior triangle of the neck
• Benign but can be disfiguring
• Associated with Turners ad Noonan Syndrome
Spot diagnosis• A 55-year-old
man presented with a 8-month history of epigastric pain, weight loss, and nausea.
• In the previous 3 months, he had lost 10 kg
Virchow’s Node• Strong indication of abdominal cancer
• Lymphatic drainage of most of the body (from the thoracic duct) enters the venous circulation via the left subclavian vein.
• The metastasis blocks the thoracic duct leading to regurgitation into the surrounding
• Differential diagnosis: lymphoma, breast cancer, infection
• Enlarged right supraclavicular lymph node tends to drain thoracic malignancies such as lung and oesphageal cancer
-Arrange bloods, CXR, Urgent Endoscopy +/-CT Scan for mets
Which nerve?
Both have left sided facial weakness…But which has had a stroke?
Bell’s Palsy
• Inflammed CN VII• Hyperacusis• Change in taste• Facial droop• 72hour onset• Treat with steroids
Ophthalmology referral: Give eye drops
Eyes• How far does
the cellulitis go?
• Is there an abscess?
• Refer early
Emergency Airways
Know• Neck triangles• Lymph node distribution• Blood supply• Neurology• Emergency airway management• How to examine a thyroid and Parotid• Common Skull/Face #• Sinuses• Headache distribution
QUESTIONS?