Download Thyroid and parathyroid

Radiology of Thyroid and parathyroid
Thyroid and parathyroid
 Normal Anatomy.
 Radiological test.
 Disease
Normal Anatomy
Embryology: Thyroid gland is derived from a tubular
structure at the base of tongue called foramen cecum
Anatomy
 Thyroid gland has two elongated lateral lobes.
 United in the middle by a median isthmus
 It is 4-6 cm in L, 1.3-18cm thick. Isthmus is 6mm thick
 Some time a pyramidal lobe is present which extend
upward from the isthmus.
 Thyroid is supplied by superior and inferior thyroid
arteries. It is extremely vascular
Thyroid Anatomy
Posterior aspect
Anterior and posterior aspect
 Thyroid produce T3, T4, and calcitonin.
 Parathyroid are two pairs(4 in number) located on the
back of thyroid. The superior pair is located near the
middle of thyroid and the inferior pair at the lower
pole on both side.
 Parathyroid are the size of a grain of rice(3-5mm). It
produce parathyroid hormone.
Normal ultrasound anatomy
Transverse image
Color Doppler image
Longitudinal image of LT
lobe
Isthmus
 Imaging modalities used for evaluation of thyroid and
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parathyroid.
Ultrasound
Radionuclide studies
CT scan
Biopsy Ultrasound/ CT guided
Ultrasound technique
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High frequency sound wave are used
Patient is supine with hyperextended neck
Both right ,left lobes and isthmus are examined
Color Doppler is used to see vascularity
Transverse and longitudinal images are taken
Ultrasound shows anatomical detail of thyroid and
adjacent blood vessels and structures.
 Normal parathyroid can not be seen with U/S,
however parathyroid adenoma and cervical nodes
involved in thyroid cancer can be sampled
Radioisotopes study
 A radionuclide is injected or given orally.
 Radioisotope taken up by thyroid/parathyroid
 Patient is put under the gamma camera to see the
uptake
 Series of images are taken in different projections
 Radionuclide studies show function. Anatomical
details are poor.
Gama camera
Normal
Normal
CT images of thyroid
CT shows clear anatomy of thyroid
gland. Test is done without and with
contrast
Diseases of thyroid
 Functional disorders. 1. Hyperthyroidism
2. Hypothyroidism
Inflammations. 1.Hashimoto 2. Sub acute etc.
 Nodular disorders.
1. simple goiter
2. Multinodular goiter
 Tumors. 1. Adenoma
1)
Carcinoma-Follicular, papillary,
Medullary, anaplastic, hurthle cells and secondary
Hyperthyroidism and gravis
disease
Hyper functioning thyroid gland
Gravis disease occur in young women. Thyroid
gland is hyper functioning and hypervascular
Inflammations
Hashimoto thyroiditis is an
autoimmune inflammation. The gland
may be hyper functioning or hypo
functioning
In the these images the gland is
diffusely enlarge and inhomogeneous
In the image below there is abscess
formation in the gland
Tumors
Adenoma is benign tumor. It is hypo echoic
well-defined
Carcinoma. Hypo echoic, irregular and
infiltrate in to the surrounding tissues.
On radionuclide imaging carcinoma is usually
cold nodule(no uptake)
Ultrasound guided biopsy
Parathyroid
Adenoma: is a benign lesion . It is well
defined and hypo echoic. It is usually
associated with hyperparathyroidism
Parathyroid carcinoma. Aggressive
lesion irregular hypo echoic.
Diagnosis is confirm by biopsy
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