Session 2 Flashcards
What is lymphadenopathy?
- Enlargement of lymph nodes
- Can involve one or several lymph nodes
- Usually identified as a neck lump
Why does lymphadenopathy occur?
- Due to infection and/or inflammation in the tissues drained by that lymph node.
- Due to malignancy - either metastases or primary malignancy (lymphoma)
- Most common cause is swollen lymph node secondary to recent infection.
What else can cause a neck lump (other than lymphadenopathy)?
- Pathology of the thyroid gland
- Congenital conditions
How can we determine the likely cause of lymphadenopathy?
- Location of lump
- Palpation findings
- Any red flags found e.g. certain associated symptoms and lymph nodes with particular characteristics to palpation.
Why is knowledge of the lymphatic drainage of the head and the neck region important?
- The presence of an enlarged lymph node may signal disease in the area it drains.
How are the lymph nodes of the neck organised?
- There are regional (superficial) and terminal (deep) groups.
Which groups of lymph nodes are regional?
- Occipital nodes
- Post auricular (also called retroauricular or mastoid) nodes.
- Submandibular nodes
- Regional lymph nodes drain specific areas
Where do regional lymph nodes lie?
- Superficially within the superficial cervical fascia
- This means they can be readily palpated when they are enlarged.
Where do terminal lymph nodes lie?
- Within the neck deep to the investing layer of deep cervical fascia.
Where do terminal lymph nodes receive their lymph from?
- They receive all the lymph from the head and neck, including lymph drained first via the regional groups.
- Deep tissues and structures of the neck e.g. larynx and thyroid gland drain directly to deep cervical lymph nodes.
Pathology of which structures may first present with a lump in the neck?
- Larynx, thyroid gland
- Because these structures drain directly to the deep lymph nodes.
Which structure are the deep cervical lymph nodes closely related to?
- Internal jugular vein within the carotid sheath
Give 2 examples of terminal cervical node
- Jugulodigastric node (tonsillar node)
- Jugulo-omohyoid node
Where is the jugulodigastric node located?
- Just below and behind the angle of the mandible.
Which structures drain to the jugulodigastric node?
- Palatine tonsil
- Oral cavity
- Tongue
- Often swollen and tender in tonsillitis and can become enlarged in cancers affecting these structures.
Which structures drain to the jugulo-omohyoid node?
- Tongue
- Oral cavity
- Trachea
- Oesophagus
- Thyroid gland
What are the supraclavicular nodes?
- A group of deep cervical nodes found in the posterior triangle, at the root of the neck on either side.
- Can enlarge in the late stages of malignancies of the abdomen and thorax.
- Receive lymph from the abdomen and thorax before drainage via thoracic duct into venous circulation.
From where does the arterial supply to the head and neck arise?
- Right and left common carotid arteries
- Vertebral arteries (branches of the subclavian arteries)
Which parts of the body are supplied by the vertebral arteries?
- Posterior neck
- Posterior parts of the brain e.g. brainstem, cerebellum
Describe the path taken by the vertebral artery
- Ascends through transverse foramina of the cervical vertebrae (except C7)
- Enters subarachnoid space between atlas and occipital bone.
- Passes up through foramen magnum
- Both vertebral arteries join to form basilar artery
Where do the common carotid arteries originate from?
- Right originates from brachiocephalic artery
- Left originates directly from arch of aorta
- Therefore left CCA is longer - it courses for about 2cm in the superior mediastinum before entering the neck.
What is the carotid sheath?
- A fascial envelope containing the CCA, IJV, and vagus nerve.
- Runs deep to sternocleidomastoid muscle
- Sheath is thin over vein but thicker around artery.
How are the contents of the carotid sheath arranged?
- Artery lies medially
- Vein is lateral
- Nerve lies behind and in between the vessels
- Sympathetic chain lies outside the sheath, medially and
How are the contents of the carotid sheath arranged?
- Artery lies medially
- Vein is lateral
- Nerve lies behind and in between the vessels
- Sympathetic chain lies outside the sheath, medially and behind it.