Neck - Part 3 Flashcards
What supplies blood to the thyroid? (2)
Superior and inferior thyroid arteries
Where does the superior thyroid artery rise from?
The ECA
Where does the inferior thyroid artery arise from?
The thyrocervical artery
Where does the superior and middle thyroid veins drain into?
IJV
Where does the inferior thyroid vein drain into?
Innominate vein
Where is the thyroid lobe located compared to the CCA and IJV? (2)
Medial and anterior
Where is the thyroid lobe located compared to the sternocleidomastoid and strap muscles? (2)
Posterior and medial
Where is the thyroid lobe located compared to the longus colli muscles?
Anterior to it
Where is the thyroid lobe located compared to the trachea and esophagus?
Anterolateral
Where is the thyroid lobe located compared to the thyroid cartilage of the larynx?
Inferior
Where is the thyroid isthmus located compared to the trachea?
Anterior
Where is the thyroid isthmus located compared to the CCA and IJV? (2)
Medial and anterior
Where are the parathyroid glands located compared to the thyroid glands?
Posterior
Where are the parathyroid glands located compared to the longus colli muscles?
Anterior
What are 3 congenital anomalies of the thryoid?
- Pyramidal lobe
- Absent isthmus
- Ectopic parathyroid gland location
Pyramidal lobe
Third lobe arising from the superior portion of the isthmus
Where does the 3rd lobe of the pyramidal lobe ascend to?
To the level of the hyoid bone
Absent isthmus
Thyroid consists of 2 distinct lobes
Where can the ectopic parathyroid gland be found near? (2)
- The carotid bifurcation
2. Posterior to the carotid artery
What is the normal height for the isthmus?
0.2-0.6cm
What are the normal measurements for an adult thyroid gland? (L, H, W)
Length = 4-6cm Height = 2cm Width = 2cm
What are the normal measurements for a pediactric thyroid gland? (L, H, W)
Length = 2-3cm Height = 0.2-1.2cm Width = 1-1.5cm
What are the normal measurements for parathyroid glands? (L, H, W)
Length = 6mm Height = 2mm Width = 4mm
What is the US appearance for the thyroid lobes and isthmus?
Homogeneous solid structures demonstrating a medium-gray echo pattern
What is the US appearance for the sternocleidomastoid and strap muscles when compared to the thyroid gland?
Hypo echoic
What is the US appearance for the longus collis muscles compared to the thyroid?
Hyper echoic
What is the US appearance of the parathyroid glands
- Flat
- Bean-shaped
- Hypo echoic structures
What is the US appearance of the CCA and IJV?
Anechoic tubular structures demonstrating internal vascular flow
What are indications for a thyroid exam? (7)
- Palpable neck mass
- Abnormal thyroid function tests
- Dysphagia
- Dyspnea
- Fatigue
- Serial evaluation of thyroid nodule(s)
- Evaluate mass from a previous medical imaging study
- CT
TSH
Thyroid stimulating hormone
What is the normal range of thyrotropin?
3-42ng/mL
What does thyrotropin do?
Regulates thyroid hormone secretion and production
What is the secretion of TSH controlled by?
Anterior pituitary gland
What is prolonged elevation of thyrotropin associated? (2)
- Hyperplasia
2. Thyroid enlargement
What is a decrease in thyrotropin the first indication of?
Thyroid gland failure
