Thyroid Gland Flashcards
The thyroid gland is located deep to what group of muscles?
Strap muscles
The thyroid gland has __ lobes
2
The thyroid gland is located anterior to…
2nd and 4th tracheal cartilages
What is the role of the isthmus?
Narrow connecting band joining the right and left thyroid lobes
Outline how the parathyroid gland associates with the thyroid?
Superior and inferior parts located on posterior surface of the thyroid lobes (4 parts in total)
A lump on the thyroid that moves superior to inferior on swallowing is known as a…
Goitre
The pyramidal lobe originates from what area of the thyroid? It is also referred to as?
Left lateral lobe
3rd thyroid lobe
Define ‘ectopic thyroid tissue’
Presence in locations other than normal anterior neck between 2-4 tracheal cartilages
Where does the thyroid gland originate embryologically?
Foramen caecum
The thyroid gland migrates inferiorly during development, and remains attached to the tongue via the ____
Thyroglossal duct
List the locations of thyroid fascia within the neck
PREVERTEBRAL: contains posterior neck muscles and cervical spine
INVESTING: all other neck compartments and 2 pairs of muscles
CAROTID SHEATHS
PRETRACHEAL
What two muscles are contained within the investing fascia?
Trapezius
Sternocleidomastoid
List the structures contained within the carotid sheaths
Vagus nerves
Deep cervical lymph nodes
Common carotid arteries (—> ICAs)
Internal jugular veins
List the structures contained within the pretracheal fascia
Oesophagus Trachea Thyroid gland Strap muscles Recurrent laryngeal nerves
Name the four strap muscles associated with the thyroid gland
Thyrohyoid
Sternohyoid
Sternothyroid
Omohyoid
Name the skeletal muscle of facial expression contained within the neck and it’s nerve supply
Platysma
CN VII
Outline the blood supply to the thyroid and parathyroid gland, and the origin of each artery
Superior thyroid artery (external carotid artery)
Ima thyroid artery (right common carotid artery)
Inferior thyroid artery (subclavian artery)
Outline the venous drainage from the thyroid and parathyroid gland, and the origin of each vein
Superior thyroid vein (internal jugular vein)
Middle thyroid vein (internal jugular vein)
Inferior thyroid vein (brachiocephalic vein)
Outline the lymphatic drainage from the thyroid and parathyroid gland
Superior deep cervical lymph nodes
Inferior deep cervical lymph nodes
Describe the course of the vagus nerve from the brainstem to the abdomen
Medulla oblongata –> jugular foramen –> carotid sheath
RHS —> lateral to trachea, on oesophagus
LHS –> lateral to aortic arch, on oesophagus
Pass with the oesophagus through the diaphragm —> Stomach surface to supply abdominal organs with parasympathetic axons
The right recurrent laryngeal nerve passes under the ___
Right subclavian artery
The left recurrent laryngeal nerve passes under the ___
Arch of the aorta
The recurrent laryngeal nerves ascend in the groove between _____ and _____
Trachea
Oesophagus
List the surgical approaches to the thyroid
Tracheostomy for a thyroidectomy
Transaxillary or transbreast with endoscopic assistance
Name the suspensory ligament of the thyroid, that attaches the thyroid to the trachea
Berry’s ligament
What is the function of the recurrent laryngeal nerves?
Motor supply to the intrinsic skeletal muscles of the larynx (vocal cords)
A unilateral injury to the recurrent laryngeal nerves would produce what symptoms?
Hoarseness/ weave voice
Weak cough
A bilateral injury to the recurrent laryngeal nerves would produce what symptoms?
Aphonia
Aspiration of foreign bodies into the lungs (can’t close rima glottidis)
Weak cough
What nerve supplies parasympathetic control to the thyroid gland?
Vagus nerve
What supplies sympathetic control to the thyroid gland?
Superior, middle and inferior ganglia of the sympathetic trunk
