Dr. Ahmed Esawy

MBBS M.Sc. MD

Dr Ahmed Esawy

ULTRASOUND

NUCLEAR IMAGING (Isotope scanning / SPECT/CT)

CT/MRI imaging

Dr Ahmed Esawy

• 4 glands: sup / inf, right / left • superior most often behind mid thyroid, deep and medial • inferior at lower tip, 20% in upper thymus • supernumerary glands - 3-5% ( Also more than four parathyroid glands

may be present and ectopic localisation may be seen.) Dr Ahmed Esawy

Parathyroids are NOT related to the thyroid (except they are neighbors in the neck). Parathyroid glands make a hormone, called "Parathyroid Hormone". You can easily live with one (or even 1/2) parathyroid gland. Everybody with a bad parathyroid gland will eventually develop bad osteoporosis--unless the bad gland is removed.

Dr Ahmed Esawy

Variations in localization of parathyroid glands.

Dr Ahmed Esawy

Ectopic Locations (5-15%): •Thyrothymic ligament •Tracheoesophageal groove •Retro esophageal space •Retropharyngeal/high cervical •Carotid sheath •Intrathyroid •Ant/post superior mediastinum •Retropharyngeal •Intrathymic •Aorto-pulmonary window

Dr Ahmed Esawy

Distribution of the ectopic sites of parathyroid

Dr Ahmed Esawy

HOME MASSEGE

The main imaging tests for the evaluation of this pathology are the ultrasound and the scintigraphy with Tc 99m Sestamibi (MIBI). In some cases a CT can be helpful, especially with glands of ectopic localization.

Dr Ahmed Esawy

WHERE SHOULD I LOOK FOR PARATHYROID GLANDS?

Dr Ahmed Esawy

normally not seen sonographically Normal parathyroid glands are very small, measuring approximately 6 mm in the craniocaudal dimension and 3-4 mm in the transverse dimension with shape like a flattened disk

Dr Ahmed Esawy

• Usually the pathological parathyroid gland appears as a hypoechoic (“black”) nodule behind the thyroid in close contact with the thyroid capsule. Upon use of the doppler feature no flow is present within the parathyroid gland.

• The size Problems with localisation may occur when the parathyroid

glands are not in contact with the thyroid tissue or other tissues which may be used to contrast it against.

• If the parathyroid gland is localised in the mediastinum it may also be

difficult to localise using ultrasonography. • Large goitres, and goitres with hypodense areas may also make

localication of parathyroid glands difficult • Usually the parathyroids may be visualised with ultrasonography if they

are more than 8-10 mm in diameter. • To be able to do biopsies it is recommended that a parathyroid

scintigraphy (sestamibi-scintigraphy) is performed before the ultrasonography is performed.

Dr Ahmed Esawy

Normal anatomy of the parathyroid glands Dr Ahmed Esawy

4 glands: sup / inf, right / left superior parathyroid glands : posterior to middle/upper portion of the thyroid lobe Inferior parathyroid glands: posterior, inferior to the inferior pole of the thyroid lobe In summary: posterior or inferior to the thyroid lobe

Dr Ahmed Esawy

normally the size of a grain of rice

Dr Ahmed Esawy

Parathyroid glands location. Sc: subctuaneous tissue E: esophagus. C: carotid artery Ms: músculo

Dr Ahmed Esawy

Parathyroid glands location. Sc: subctuaneous tissue. Ms: músculo Dr Ahmed Esawy

2—Sonogram of 25-year-old woman with possible thyroid enlargement (thyroid was normal). Note subtle isoechoic parathyroid gland inferior to lower pole of thyroid (arrows). Normal parathyroid glands are uncommonly seen on sonography because of their small size.

Dr Ahmed Esawy

PARATHYRIOD PATHOLOGY

Dr Ahmed Esawy

The ONLY purpose of the parathyroid glands is to regulate the calcium level in our bodies within a very narrow range

Dr Ahmed Esawy

Control of mineral metabolism by parathyroid hormone (PTH)

Dr Ahmed Esawy

Dr Ahmed Esawy

Parathyroid disorder • Congenital Parathyroid Gland Cyst agenesis ,hypoplasia supernumerary glands congenital ectopias • Hyperparathyroidism (HPT) isolated syndromic

Familial isolated hyperparathyroidism (FIHP) Multiple endocrine neoplasia type 1 (MEN1)

• Hypoparathyroidism • Cancerous forms of parathyroid disease

Dr Ahmed Esawy

Hereditary Hyperparathyroidism Syndromes Familial hyperparathyroidism includes a group of disorders in which primary hyperparathyroidism (PHPT) is inherited, usually as an autosomal dominant trait. These include: multiple endocrine neoplasia type 1 (MEN1), MEN2A, MEN4, familial hypocalciuric hypercalcemia (FHH or FBHH), neonatal severe hyperparathyroidism (NSHPT), autosomal dominant moderate hyperparathyroidism (ADMH), hyperparathyroidism-jaw tumor syndrome (HPT-JT), familial isolated hyperparathyroidism (FIHPT) . PHPT is a rare condition in children and young adults; and when present, it is often in the context of a hereditary hyperparathyroidism syndrome FIHPT Syndrome

Dr Ahmed Esawy

Hyperparathyroidism

SECONDARY PRIMARY PHPT

ACQUIRED HEREDITARY FAMILIAIL

TERTAIRY HP

Dr Ahmed Esawy

Hyperparathyroidism

isolated syndromes

Dr Ahmed Esawy

PRIMARY Hyperparathyroidism

ACQUIRED Adenomas Hyperplasia carcinomas

HEREDITARY / FAMILIAIL multiple endocrine neoplasia type 1 (MEN1), MEN2A, MEN4, familial hypocalciuric hypercalcemia (FHH or FBHH), neonatal severe hyperparathyroidism (NSHPT), autosomal dominant moderate hyperparathyroidism (ADMH) hyperparathyroidism-jaw tumor syndrome (HPT-JT), familial isolated hyperparathyroidism (FIHPT)

Dr Ahmed Esawy

1ry hyperparathyroidism acquired

Caused by • single Adenoma 80% • Double Adenoma 5-10% • Four-Gland Hyperplasia 5-10% also MEN, ectopic • Parathyroid carcinoma 1% elevated PTH • Women are affected two or three times more frequently than men • The patient usually present with signs symptoms of

hyperparathyriodism

Dr Ahmed Esawy

PTH→ +ve osteoclasts→bone resorption, Ca reabsorption from tubules, Ca absorption from the gut → ↑ serum and urinary Ca and ↓ serum P with ↑ urinary P. Dr Ahmed Esawy

typical situation of a patient with parathyroid disease--one of the parathyroid glands grows into a tumor and makes too much hormone Other three may be normal

Dr Ahmed Esawy

Causes of Secondary hyperparathyroidism

- Hypocalcemia (rickets, osteomalacia or renal failure ,intestinal malabsorption) 2ry HPT. - Hyperplasia of parathyroid gland (osteosclerosis rugger jersey spine, subperiosteal erosion is the prominent feature. Brown tumours are rare, vascular calcification common.

Dr Ahmed Esawy

Tertiary hyperparathyroidism

►Occurs in pts. with 2ry HPT who develop autonomous parathyroid adenoma.can develop after long-standing secondary HPT in Chronic kidney failure /transplantation

►HPT fails to respond to ttt of underlying cause.

Dr Ahmed Esawy

Sonography in Primary Hyperparathyroidism

Dr Ahmed Esawy

Ultrasound has a central role in patients with primary hyperparathyroidism. It may be used pre-and peroperatively for 1) Localisation of parathyroid glands

2) Indentifying number of supposed pathological glands 3) Identifying thyoid pathology and thus be a part of pre-operative planning of the extent of surgery 4) Performing biopsies from the thyroid and sometimes also the parathyroid glands

Dr Ahmed Esawy

Algorithm for preoperative localization and surgical treatment of primary hyperparathyroidism.

Dr Ahmed Esawy

parathyroid adenomas

Dr Ahmed Esawy

WHAT DO PARATHYROID ADENOMAS LOOK LIKE?

Small adenoms is oviod .large adenomas is oblong (often parallel to long axis of neck) may be lobulated or bullous homogeneous solid mass hypoechoic to the thyroid gland ,extrathyriodal mass with well defined margins. DOPPLER show Hypervascularized, except when they are small sized or very deep located. Doppler show polar arterial structure The "vascular arch" is a typical finding. It must be distinguished from glands presenting a central hilar vascularity.

Dr Ahmed Esawy

Most parathyroid adenomas are located posterior or immediately inferior to the thyroid lobe and medial to the carotid. Most parathyroid adenomas are single 5 % multiple Peak incidence 3rd -5th decade 3% have an ectopic location The main imaging test for the evaluation of this pathology are the ultrasound and the scintygraphy with Tc 99m Sestamibi. In some cases a CT can be helpful, especially with glands of ectopic localization.

Dr Ahmed Esawy

Dr Ahmed Esawy

US • Effective, noninvasive and inexpensive • Limitations are operator dependent, restriction to lesions in the neck • Often combined with sestamibi

Dr Ahmed Esawy

ADENOMA OF THE LEFT INFERIOR PARATHYROID GLAND. Images at the top: cervical ultrasound, axial (panel A) and longitudinal (panel B) scans. Image at the bottom: axial CT image. Lesion was unnoticed on CT.

Dr Ahmed Esawy

ADENOMA OF THE LEFT INFERIOR PARATHYROID GLAND. It is located caudal to the inferior pole of the left thyroid lobe. Axial scan (panel A), longitudinal scan (panel B y C) y longitudinal scan with color Doppler imaging ( panel D)

Dr Ahmed Esawy

ADENOMA OF THE UPPER RIGHT PARATHYROID GLAND 84-year-old male. Routine analysis Ca 14 mgr/dl and PTH: 200 Ultrasound, axial scan (panel A) and longitudinal scan (panel B): hypoechoic rounded nodule adjacent to the posterior margin of the superior pole in the right thyroid lobe Parathyroid scintigraphy (C) was positive (arrow). The patient had normal ultrasound and scintigraphy done 2 years before Dr Ahmed Esawy

Normal appearance of parathyroid adenoma on ultrasound Dr Ahmed Esawy

ARE PARATHYROID ADENOMAS ALWAYS HYPOECHOGENIC? Occasionally adenomas with atypical appearances are found: cystic, heterogeneous , hyperechogenic ( or with calcifications.

Dr Ahmed Esawy

Atypical large size parathyroid adenomas Dr Ahmed Esawy

Atypical parathyroid adenoma. Ultrasound: axial (A) and longitudinal (B) scan

Dr Ahmed Esawy

WHAT SIZE SHOULD THEY HAVE? Average measure between 0.8 and 1.5 cm. Smaller sizes are less frequent: microadenomas Macroadenomas: differential diagnosis with carcinoma must be made

Dr Ahmed Esawy

Parathyroid microadenoma. Ultrasound:Axial (A)and longitudinal (B) scan

Dr Ahmed Esawy

Parathyroid Adenoma Minimally invasive surgery requires localization of the abnormal gland US: solid, homogeneous hypoechoic, flat or soft feeding vessel enters pole/ arcs along edge Tech 99m Sestamibi for localization if US unsuccessful rapid serum PTH levels intraoperative

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Sagittal view of the left neck showing the thyroid gland with multiple nodules within the gland. The nodule at the inferior edge of the gland appears to be just outside the gland and has a demarcating capsule. Dr Ahmed Esawy

Transverse view demonstrating the nodule in the region just inferior to the left lobe of the thyroid bed, with an echogenic curv

Dr Ahmed Esawy

An arc of prominent vessels surrounding and leading into the nodule is demonstrated Parathyroid adenoma

Dr Ahmed Esawy

Left inferior parathyroid adenoma

Dr Ahmed Esawy

Right inferior parathyroid adenoma

Dr Ahmed Esawy

Parathyroid adenoma. The lesion is postero-inferior to the thyroid with a thin highly reflective capsule

Dr Ahmed Esawy

Parathyroid adenoma of the same echogenicity as the thyroid parenchyma. The parathyroid mass can only be separated from the thyroid by the highly reflective capsule.

Dr Ahmed Esawy

Very large right superior parathyroid adenoma associated with brown tumour of the left clavicle.

Dr Ahmed Esawy

44-year-old woman with hyperparathyroidism due to right inferior parathyroid adenoma. Resected gland weighed 629 mg, nearly 15 times weight of a normal gland (40–50 mg). A, Sonogram shows typical hypoechoic adenoma (arrows) deep in relation to lower pole of thyroid. B, Color Doppler sonogram shows peripheral feeding vessel (arrow) characteristic of parathyroid adenomas. Also note typical arc or rim vascularity

Dr Ahmed Esawy

55-year-old woman with primary hyperparathyroidism due to large left superior adenoma. A, Sonogram shows hypoechoic nodule suspected of being parathyroid medial to common carotid artery (arrow). B, Graded compression sonogram increases conspicuity of adenoma (arrows). Dr Ahmed Esawy

25-year-old woman with Hashimoto’s thyroiditis. A and B, Sonograms show how prominent central compartment lymph nodes (arrows) may mimic adenomatous parathyroid glands. C, Color Doppler sonogram may aid in differentiating between lymph nodes and adenomas: Lymph nodes are supplied by a central hilar vessel (arrow), whereas vessels that supply adenomas typically enter either pole.

Dr Ahmed Esawy

67-year-old woman with hyperparathyroidism and left tracheoesophageal groove adenoma that could easily be mistaken for posterior thyroid nodule. Peripheral, polar vascularity seen on color Doppler sonogram helps to identify this as adenoma. Subsequent parathyroidectomy preformed at time of total thyroidectomy revealed this to be a supernumerary hyperplastic parathyroid gland.

Dr Ahmed Esawy

52-year-old woman with hyperparathyroidism and right superior parathyroid adenoma. A, Early-phase 99mTc-sestamibi SPECT image shows physiologic uptake in salivary glands and thyroid gland, with focus of more intense uptake overlying superior pole of right thyroid lobe (arrow). B, Two-hour delayed SPECT image shows radiotracer retention in adenoma (arrow) but clearing of tracer from overlying thyroid

Dr Ahmed Esawy

A 55-year-old woman with parathyroid adenoma. A, B. Coronal images from a technetium- 99m sestamibi parathyroid scan (A, early phase; B, delayed phase) demonstrate a single area of increased uptake in the right lower neck. C, D. Gray-scale sonograms (C, axial scan; D, longitudinal scan) demonstrate a large well-defined hypoechoic solid mass posteroinferior to the right lobe of the thyroid gland.

Dr Ahmed Esawy

A 73-year-old woman with parathyroid adenoma with characteristic feeding vessels. A longitudinal sonogram shows a hypoechoic solid mass with multiple feeding vessels from the lower pole margin of the thyroid gland.

Dr Ahmed Esawy

A 63-year-old man (A) and a 34-year-old woman (B) with suspicious parathyroid incidentalomas (PTIs). A. An axial sonogram depicts an oval, well-defined hypoechoic solid PTI (arrow). The lesion was proven to be a parathyroid lesion by a fine needle aspiration-parathyroid hormone (FNA-PTH) assay. B. An axial sonogram shows an enlarged thyroid gland with heterogeneous parenchymal echogenicity and a flat hypoechoic nodular lesion (arrow) located posterior to the gland. Many lymphocytes were found up on cytologic examination and an FNA-PTH assay found low level of parathyroid hormone. A flat nodular lesion, suspected to be a PTI, was proven to be an enlarged perithyroidal lymph node associated with chronic thyroiditis. Dr Ahmed Esawy

A 51-year-old woman with very large nonfunctioning parathyroid cyst. A. An axial sonogram shows the parathyroid cyst (PC) (6.2 cm, 58.1 mL) below the right lower pole of the thyroid gland. The PC recurred two 2 months after simple aspiration. B. An axial sonogram shows the transisthmic approach of an 18-gauge needle (arrow) into the PC. C.An axial sonogram shows the PC after it was filled with instilled ethanol via an 18-gauge needle (arrow) after the complete evacuation of the cystic fluid. D. An axial sonogram shows the PC with a much smaller size (2.5 cm, 3.3 mL) 1 month after ethanol ablation. T, trachea; C,common carotid artery.

Dr Ahmed Esawy

parathyroid adenoma Dr Ahmed Esawy

Transverse gray scale images of very large (A) and small (B) parathyroid adenomas in typical extrathyroidal locations. Adenomas typically appear homogeneously hypoechoic with well-defined margins. The adenomas measure 1.8 × 1.5 cm (A) and 0.7 × 0.5 cm (B).

Dr Ahmed Esawy

Enlarged Extrathyroidal Feeding Artery

Parathyroid adenoma imaged without (A) and with (B) power Doppler sonography showing the presence of a large extrathyroidal feeding vessel with a polar insertion.

Dr Ahmed Esawy

Large parathyroid adenoma without (A) and with (B) power Doppler sonography showing the presence of an extrathyroidal feeding vessel inserted at the pole of the long axis of the adenoma

Dr Ahmed Esawy

Parathyroid adenoma in longitudinal (A) and transverse (B) views showing a rim of peripheral vascularity

Dr Ahmed Esawy

Parathyroid adenoma adjacent to the carotid artery imaged in the transverse plane without (A) and with (B) power Doppler sonography. The peripheral vascular pattern of the adenoma easily distinguishes it from the carotid artery and jugular vein.

Dr Ahmed Esawy

Longitudinal images of right (A) and left (B) lobes of the thyroid showing asymmetry of vascularity at the inferior aspect of the gland secondary to the presence of a left inferior parathyroid adenoma. The adenoma is shown on the right in B, and diffuse hyperemia is shown in the adjacent thyroid gland and surrounding tissues.

Dr Ahmed Esawy

Transverse images without (A) and with (B) compression, which improves visualization of the adenoma. The relationship between this deep adenoma and the longus colli muscle is also demonstrated

Dr Ahmed Esawy

Transverse images without (A) and with (B) compression, showing dramatic improvement of visualization of a very small adenoma

Dr Ahmed Esawy

Transverse images without (A) and with (B) compression, showing dramatic improvement of visualization of a small adenoma

Dr Ahmed Esawy

Hyperparathyroidism (QPTH, 243 pg/mL) and 752- mg left superior parathyroid adenoma at minimally invasive parathyroidectomy in a 47-year-old woman. A, Sagittal sonography shows a 1.4-cm hypoechoic superior parathyroid adenoma (asterisk) deep to the mid pole of the left thyroid lobe. B, Immediate and delayed Tc 99m sestamibi SPECT. The immediate study (left) shows asymmetric (left greater than right) thyroid uptake. The delayed study (right) shows mild focal residual uptake posterior to the mid pole of the left thyroid lobe

Dr Ahmed Esawy

Hyperparathyroidism (QPTH, 281 pg/mL) and 322-mg left superior parathyroid adenoma at minimally invasive parathyroidectomy in a 66 year old man. A, Sagittal sonography shows an elongated hypoechoic parathyroid adenoma (arrows) deep to the upper pole of the left thyroid lobe. B, Immediate and delayed Tc 99m sestamibi SPECT. The immediate study (left) shows perhaps slightly asymmetric right lobe tracer uptake. The delayed study (right) shows no convincing tracer retention

Dr Ahmed Esawy

Longitudinal view of a thyroid nodule without (A) and with (B) power Doppler sonography. Although the thyroid nodule (calipers) has peripheral vascularity, it lacks a well-defined extrathyroidal feeding artery with polar insertion. The hyperechogenicity and location within the thyroid gland are also helpful for differentiating this nodule from a parathyroid adenoma.

Dr Ahmed Esawy

Classic parathyroid adenoma identified on ultrasonography

Sagittal ultrasonographic image shows a hypoechoic, well-defined mass (A) just below the inferior pole of the right thyroid gland (*). B, Transverse ultrasonographic image with color flow Doppler shows the increased peripheral arch of vascularity of the mass frequently seen with adenomas

Dr Ahmed Esawy

Large parathyroid adenoma without (B) and with (A) power Doppler sonography. In addition, a hypoechoic intrathyroidal nodule is shown, superficial to the adenoma. An extrathyroidal feeding vessel inserted at the pole of the long axis of the adenoma is shown, distinguishing it from the thyroid nodule.

Dr Ahmed Esawy

Longitudinal images of a parathyroid adenoma deep to the thyroid gland without (A) and with (B) power Doppler sonography. The hyperechogenicity of this pathologically proven adenoma was unusual and seen only in this adenoma. An extrathyroidal feeding artery inserts at the pole of the long axis of the adenoma.

Dr Ahmed Esawy

A, Longitudinal gray scale image showing a deep hypoechoic structure in the expected location of the longus colli muscle. B, Power Doppler image showing the presence of an extrathyroidal feeding artery and peripheral vascularity of a deep adenoma apposed just superficial to the longus colli muscle. Compression was used in both images.

Dr Ahmed Esawy

A and B, Transverse gray scale images of a retrocarotid parathyroid adenoma without (A) and with (B) compression. C and D, Same adenoma in longitudinal images without (C) and with (D) power Doppler sonography. The edge-shadowing artifact of the carotid artery obscures the adenoma, which is only visible with compression and adjustment of the acoustic window. An extrathyroidal feeding artery is also shown.

Dr Ahmed Esawy

a, b Neck ultrasonography of a 31-year-old female patient with primary hyperparathyroidism shows evidence of double adenoma involving the right and left inferior parathyroid glands. The left inferior parathyroid lesion was predominantly cystic. c, d Tc-99m sestamibi scintigraphy and SPECT revealed only the right inferior parathyroid adenoma and the left inferior lesion seen on ultrasonography was not seen. e High-power photomicrograph (×100, H&E stain) of the left inferior parathyroid lesion, which was negative on scintigraphy and SPECT, shows acinar dilatation (arrowheads) and haemorrhage Dr Ahmed Esawy

Dr Ahmed Esawy

Atypical ultrasound features of parathyroid tumours

Atypical ultrasound features of parathyroid lesions pose a diagnostic challenge. Awareness of these features would help improve lesion detection. Teaching points 1.Cystic change is significantly related to the size, weight and measured parathyroid hormone levels. 2.Cystic change in parathyroid tumours indicated a slightly higher risk of malignancy. 3.Heterogeneous parathyroid adenomas are larger in size and heavier, and they have higher PTH levels. 4. Awareness of atypical ultrasound features will improve preoperative clinical prediction

Dr Ahmed Esawy

a Neck ultrasonography of 48-year-old male patient with primary hyperthyroidism showed a predominantly cystic right inferior parathyroid lesion with internal septations

Dr Ahmed Esawy

a Neck ultrasonography of a 21-year-old female patient with primary hyperthyroidism showed haemorrhagic and cystic degeneration in the right superior parathyroid adenoma

Dr Ahmed Esawy

Neck ultrasonography of a 55-year-old male patient showed a right inferior parathyroid lesion with hypoechoic and hyperechoic components.

Dr Ahmed Esawy

Neck ultrasonography of a 42-year-old male patient with parathyroid carcinoma showed a heterogeneous, more rounded left inferior parathyroid lesion with areas of cystic degeneration and ill-defined microlobulated margins

Dr Ahmed Esawy

Neck ultrasonography showed a calcified right inferior parathyroid adenoma in a 27-year-old male patient with primary hyperparathyroidism. An echogenic rim around the lesion could be seen inspite of calcification

Dr Ahmed Esawy

SHOULD I NECESSARILY FIND ANYTHING? False negative: - Minimally enlarged adenoma

- Adjacent lesions in an enlarged or multinodular

thyroid

- Ectopic parathyroid adenoma

Dr Ahmed Esawy

False negative: parathyroid adenoma in multinodular goiter Dr Ahmed Esawy

Retroesophageal adenoma Dr Ahmed Esawy

Ectopic adenoma Dr Ahmed Esawy

INTRATHYROIDAL ADENOMA Ultrasound shows a very vascularized and welldefined hypoechogenic solid nodule (mid third of left thyroid lobe)

Dr Ahmed Esawy

Visualization of an Ectopic Parathyroid Adenoma in the Patient with the Use of Scintigraphy, PET-MRI, and PET-CT. metabolically active mass behind the left sternoclavicular joint.

Dr Ahmed Esawy

Ectopic Parathyroid Adenoma Localized by Tc-99m Sestamibi SPECT/CT Localization Prior to Re-operation is Useful

Anterior static Sestamibi images, done immediately, and at 20 minutes and 3 hours show a focal lesion superior and lateral to the right thyroid lobe.

Dr Ahmed Esawy

Ectopic Parathyroid Adenoma Localized by Tc-99m Sestamibi SPECT/CT Localization Prior to Re-operation is Useful

SPECT/CT in tomographic, CT and fused images in the axial, sagittal and coronal plane, showing focal increased uptake lateral to the right hyoid bone (white arrow).

Dr Ahmed Esawy

Normocalcemic primary hyperparathyroidism (NPHPT) is a condition characterized by elevation of the parathyroid hormone (PTH) in the presence of normal serum calcium and the absence of secondary causes, such as renal insufficiency, vitamin D deficiency, use of medications such as hydrochlorothiazide and lithium, as well as hypercalciuria and malabsorption states.

Dr Ahmed Esawy

Is it a Parathyroid Adenoma? hypoechoic oval nodules near thyroid in 2.3% FNA – 24% parathyroid

58% thyroid 11% lymph node 8% nondiagnostic

Dr Ahmed Esawy

Parathyroid adenomas not important unless biochemically active

Dr Ahmed Esawy

IF THERE IS A NODULE, IS IT NECESSARILIY AN ADENOMA?

False positive:

- Cervical Lymph node - Thyroid nodule - Anatomical structures

Prominent blood vessel Esophagus Longus colli muscle

Dr Ahmed Esawy

False positive: lymph node Dr Ahmed Esawy

Extrathyroidal lymph node without (A) and with (B) color Doppler sonography. Although the gray scale image shows a lesion that is indistinguishable from a parathyroid adenoma, the color Doppler image shows central hilar vascularity. This node proved to contain metastatic thyroid adenocarcinoma.

Dr Ahmed Esawy

False positive: adenopathy Dr Ahmed Esawy

FALSE POSITIVE: Thyroid nodule Dr Ahmed Esawy

False positive: normal anatomic structures Dr Ahmed Esawy

IF THE NODULE IS SMALL, COULD IT BE A NORMAL PARATHYROID? Normal parathyroid glands are usually not visualized. The average size is 5x3x1mm, and they are isoechogenic to normal thyroid. )

Dr Ahmed Esawy

Normal parathyroid gland Dr Ahmed Esawy

PARATHYRIOD CT IMAGING

Dr Ahmed Esawy

PARATHYROID ADENOMA Definition: Benign neoplasm of the parathyroid parenchymal cells, including chief cells and/or oncocytic cells.

May be associated with hyperparathyroidism-jaw tumor syndrome (HPT-JT):

Autosomal-dominant disorder

Characterized by: – Parathyroid adenoma or carcinoma – Fibro-osseous lesions of the jaw (e.g., ossifying fibroma of mandible or maxilla): 30% of cases – Renal cyst, hamartoma, carcinoma: 20% of cases

Dr Ahmed Esawy

Dr Ahmed Esawy

On CT adenoma appear as well-defined nodules usually hyperenhanced in relation to the thyroid gland.

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

A: Early Sestamibi scan (thyroid + parathyroid) B: Late Sestamibi scan (left lower parathyroid) C: SPECT showing parathyroid D: Low dose CT E: Fused image F: Ultrasound showing 8mm parathyroid adenoma (between calipers)

Dr Ahmed Esawy

SPECT/CT of mediastinal parathyroid adenoma Top Row: Sestamibi scan Middle Row: low dose CT Bottom Row: fused images

Dr Ahmed Esawy

40-year-old woman who presented with recurrent hypercalcemia and hyperparathyroidism after resection of both left-sided glands. Contrast-enhanced CT scan shows brisk enhancement of 8-mm soft-tissue nodule (arrow) in mediastinum that correlated anatomically with focus of radiotracer retention in mediastinum on prior sestamibi SPECT. This was found to be a hyperplastic right inferior parathyroid gland

Dr Ahmed Esawy

The role of four-dimensional (4D) CT Higher sensitivity than ultrasound, but involves radiation •4D-CT is derived from 3D CT scanning, with added dimension from changes in perfusion of contrast over time, which allows to characterize hyperfunctioning parathyroid glands

Dr Ahmed Esawy

Dr Ahmed Esawy

The role of four-dimensional (4D) CT is to enable accurate localization of the parathyroid adenoma in eutopic and ectopic locations and to depict multiglandular disease. Characteristic contrast enhancement pattern for a parathyroid adenoma is peak enhancement at the arterial phase, washout of contrast material from the arterial to delayed phase, and low attenuation on the non–contrast enhanced images. The morphologic imaging findings of parathyroid adenomas include central low attenuation change, lobulated margins, and a polar vessel sign. Dr Ahmed Esawy

Images in a 73-year-old man with a left carotid space parathyroid adenoma; 4D CT study shows a parathyroid lesion with typical enhancement characteristics and morphology. (a) Nonenhanced phase axial image shows an oval lesion (arrow), lateral to the pyriform sinus of the hypopharynx and anterior to the left common carotid artery (CCA). The mass has low attenuation. (b) Arterial phase axial image reveals the lesion (arrow) is vividly enhancing. There is a central nonenhancing region. (c) Delayed phase axial image shows washout of contrast material with decreasing attenuation (arrow) compared with the arterial phase. Note that other structures such as a level IB lymph node (LN), submandibular gland (SMG), and muscles do not have marked washout of contrast material from the arterial to the delayed phase. (d) Coronal reformatted image in the arterial phase demonstrates oval lesion (arrow) that is separate from the thyroid gland (Thy).

Dr Ahmed Esawy

a 52-year-old woman with a large left parathyroid adenoma. (a) Coronal arterial phase 4D CT image shows a lesion measuring up to 4 cm in craniocaudal dimension (straight arrows), inferior to the left thyroid lobe and extending between the left common carotid artery (CCA) and brachiocephalic artery (BC). There is an enlarged inferior thyroid artery that terminates at the superior pole of the lesion (curved arrow). Note the contralateral normal inferior thyroid artery (arrowhead). (b) Arterial phase axial image shows the lesion (arrow) enhances and has similar attenuation as sequestered thyroid tissue (arrowhead). (c) Axial image in the nonenhanced phase is helpful in differentiating between high attenuation thyroid tissue (arrowhead) and the lower attenuation candidate lesion (arrow).

Dr Ahmed Esawy

Images in a 78-year-old woman with left-sided multiglandular disease. (a) Arterial and (b) delayed phase axial 4D CT images at the level of the thyroid isthmus show a lesion (arrow) posterior to the superior left thyroid lobe, which has early vivid enhancement and rapid washout of contrast material. (c) Arterial and (d) delayed phase axial CT images at the thoracic inlet show a second rounded lesion (arrow) inferior to the left thyroid lobe, which has a similar enhancement pattern to the first lesion. Note a significant streak artifact (*) caused by the beam hardening from the clavicles and contrast material in the veins, especially on the arterial phase image. Lesions in or close to these artifacts could be missed.

Dr Ahmed Esawy

Images in a 74-year-old woman with thyroid nodule mimicking a parathyroid adenoma at 4D CT. (a) Axial nonenhanced image shows a low-attenuation candidate lesion (arrow) at the posterior aspect of the left lower thyroid lobe. Subsequent arterial phase images were technically poor because the patient had aortic regurgitation and arterial phase imaging was performed too early. Since the radiologist was at the scanner, two additional contrast-enhanced phases were performed. (b) An early delayed phase axial CT image at 40 seconds from the start of contrast material injection shows the lesion (arrow) enhances more relative to the thyroid gland, and (c) a routine delayed phase axial CT image at 100 seconds from the start of contrast material injection shows washout of contrast material (arrow). This was reported as a parathyroid lesion but was found to be a thyroid nodule at surgery.

Dr Ahmed Esawy

Images in a 69-year-old woman with a right parathyroid adenoma. (a) Axial, (b) coronal, and (c) sagittal arterial phase 4D CT images show a vividly enhancing lesion (straight arrow) posterior and inferior to the lower pole of the right thyroid lobe. This lesion contains a central nonenhancing focus best seen on the axial image. There is a characteristic tortuous polar vessel at the superior aspect of the lesion (curved arrow) seen on axial and sagittal images. Note that a left level VI lymph node (arrowhead) seen on the axial and coronal images is in the same location as the parathyroid adenoma but is not enhancing on arterial phase and has no associated vessels.

Dr Ahmed Esawy

Images in a 45-year-old woman with a right carotid space parathyroid adenoma. There was a prior history of unsuccessful neck exploration. (a) Axial arterial phase 4D CT image shows a lesion (arrow) in the right carotid space, anterior to the common carotid artery. The lesion does not have vivid arterial enhancement,but there is a characteristic polar artery that courses around the lesion (arrowhead). (b) Axial delayed phase image shows washout of contrast material (decreasing attenuation) in the lesion (arrow). (c) Sagittal reformatted arterial phase image shows the lesion has a lobulated superior margin (arrowhead). The polar vessel and lobulated contour help to differentiate it from a lymph node. (d) Axial gadoliniumenhanced T1-weighted fat-suppressed magnetic resonance image of the neck demonstrates contrast enhancement of the lesion (arrow), but the morphologic feature of peripheral artery and the lobulations could not be seen because of the lower resolution.

Dr Ahmed Esawy

Images in a 47-year-old woman with multiglandular disease in the retropharynx. She had a history of an unsuccessful neck exploration, but the superior parathyroid glands were unable to be identified. (a) Arterial and (b) delayed phase axial 4D CT images show the two lesions (arrows) in the retropharyngeal space at the level of the pyriform sinuses with early vivid enhancement and rapid washout of contrast material. (c) Arterial phase image reformatted in the coronal plane shows bilateral lesions (arrows) in the retropharyngeal space. The larger right lesion has a polar vessel, which is tortuous (arrowhead). This is a characteristic ectopic location for the superior parathyroid gland.

Dr Ahmed Esawy

Images in a 61-year-old woman with multiglandular disease in the posterior mediastinum arising from the superior parathyroid glands. (a) Axial CT image shows a candidate lesion (arrow) composed of cystic (*) and solid components in the posterior mediastinum. (b) Coronal 99mTc sestamibi images at 10 minutes (left) and 2 hours (right) show two focal areas of uptake and focal persistent tracer activity, respectively, below the level of the left thyroid gland (arrows), corresponding to the abnormality seen at CT. Note that the cystic component on the right seen at CT does not have activity. At surgery the patient had bilateral parathyroid lesions that had descending into the posterior mediastinum. Despite the mediastinal location, this is more characteristic of superior parathyroid adenomas because these adenomas fall posterior and inferior to the tracheoesophageal groove when enlarged. Inferior parathyroid adenomas are found along the thyrothymic ligament and are located in the anterior mediastinum. Dr Ahmed Esawy

ultrasound (US). ( a ) US image in the longitudinal plane, rotated clockwise 90° to match the CT sagittal reconstructed projection, demonstrates the parathyroid adenoma (1.1 × 0.5 × 0.5 cm) ( thick arrow ) along the inferior aspect of the left lobe of the thyroid ( thin arrow ). ( b ) US image in the transverse plane demonstrates the parathyroid adenoma ( arrow ) inferior to the left lobe of the thyroid lateral to the trachea (T) and medial to the carotid (C) that correlates with the position of the parathyroid adenoma documented on 4D-CT

Case 1 Dr Ahmed Esawy

Same patient before technetium-99 m sestamibi (Tc-99 m MIBI). ( a ) Transverse, sagittal, and coronal static images of the neck and chest 30 min following the intravenous injection of 25 mCi of Tc-99 m MIBI demonstrate uptake in parathyroid adenoma ( black arrow ). ( b ) SPECT/CT images, obtained after the initial set of immediate postinjection images, demonstrate type E parathyroid gland ( red arrow )

Case 1 Dr Ahmed Esawy

Same patient before 4D-CT. ( a ) Axial postcontrast computed tomography (CT) scan reveals an enhancing parathyroid adenoma (0.8 × 0.5 × 0.9 cm) underlying the posterior surface of the left thyroid lobe ( arrow ). ( b ) Sagittal reconstructed maximal intensity projection (MIP) image demonstrates that the parathyroid adenoma is along the inferior aspect of the left thyroid lobe ( arrow )

Case 1 Dr Ahmed Esawy

Another patient US. ( a ) US image in the transverse plane demonstrates a parathyroid adenoma (3.2 × 1.3 × 0.9 cm) ( arrow ) in the paraesophageal region inferior to the left thyroid lobe lateral to the trachea (T) and medial to the carotid (C) that correlates with the position of the parathyroid adenoma documented on 4D-CT. ( b ) US image in the longitudinal plane demonstrates the parathyroid adenoma ( thin arrow ) inferior and posterior to the left thyroid ( th ). Incidental note is made of a multinodular thyroid. The dominant nodules in the right (0.8 cm) and left lobe of the thyroid (1.4 cm) ( thick arrows ) were documented as colloid nodules on US-guided biopsy prior to the MIP

Case 2

Dr Ahmed Esawy

Same Another patient technetium-99 m sestamibi (Tc-99 m MIBI). ( a ) Transverse, sagittal, and coronal static images of the neck and chest 30 min following the intravenous injection of 30 mCi of Tc-99 m MIBI demonstrate avid focal tracer in left paraesophageal region in the tracheoesophageal groove ( arrow ). ( b ) SPECT/CT images, obtained after the initial set of immediate postinjection images, demonstrate type C parathyroid adenoma ( red arrow )

Case 2 Dr Ahmed Esawy

Same Another patient CT. ( a ) Axial noncontrast CT shows a soft tissue attenuation parathyroid adenoma separate and posterior to the left thyroid lobe ( arrow ) along the paraesophageal region. ( b ) Following contrast administration, the parathyroid adenoma enhances avidly during the arterial phase of the contrast bolus. ( c ) On the later phase of the study, contrast has washed out quickly from the adenomatous parathyroid ( arrow ). ( d ) Coronal reconstructed MIP images demonstrate the parathyroid adenoma relative to the thyroid gland and adjacent structures. ( e ) Sagittal reconstructed MIP images demonstrate the parathyroid adenoma relative to the thyroid gland and adjacent structures

Case 2

Dr Ahmed Esawy

Case 3 Dr Ahmed Esawy

CT. ( a ) Axial noncontrast CT shows a soft tissue attenuation parathyroid adenoma (0.9 × 0.5 × 1.9 cm) in the etroesophageal region ( arrow ). Note that the patient has had total thyroidectomy. ( b ) Following contrast administration, the parathyroid adenoma shows early enhancement ( arrow ). ( c ) Following contrast administration, the parathyroid adenoma shows early washout ( arrow ). Note the left common carotid artery ( arrowhead ). ( d ) Sagittal reconstructed MIP images demonstrate the parathyroid adenoma anterior to the C5 and C6 vertebral bodies ( arrow ) Case 3 Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

39-year-old woman with left superior adenoma showing typical MRI signal characteristics. A, T2-weighted MR image shows increased T2 signal in adenoma (arrow) relative to thyroid gland and surrounding soft tissues. B, Axial T1-weighted MR image shows typical intermediate T1 signal (arrow) seen in adenomas

C, Gadolinium-enhanced T1-weighted image with fat suppression shows intense enhancement typical of adenomas (arrow). These imaging characteristics can be indistinguishable from those of lymph nodes and thus must be interpreted in clinical context and in concert with other imaging techniques

Dr Ahmed Esawy

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A, Unenhanced CT scan at the level of the lower poles of the thyroid gland shows no discrete adenoma. B, Immediate first-pass image following contrast administration shows a tiny, avidly enhancing adenoma in the right paraesophageal region (anterior to *). C, Second pass at 60 seconds shows some washout of enhancement, which is clearly less than on the immediate postcontrast scan. D, Last pass delayed image at 90 seconds shows little enhancement of the adenoma, which is still readily identifiable. On another patient:

E, Coronal reconstructed CT image from immediate first-pass enhanced CT scan shows a large adenoma below the inferior pole of the left thyroid lobe (arrow).

Dr Ahmed Esawy

F, Coronal maximum intensity projection image in anterior projection shows the adenoma (arrow). G, Coronal maximum intensity projection image in the posterior projection shows the adenoma (*) posterior to the common carotid artery.

Dr Ahmed Esawy

Dr Ahmed Esawy

Selective arteriography in conjunction with venous sampling for PTH •Requires catheterization of multiple veins in the neck and mediastinum, from which blood samples are obtained with rapid PTH measurement in angio suite •Parathyroid adenomas have increased vascularity, demonstrating a characteristic blush on arteriography •Indicated for patients requiring re-exploration with negative or discordant imaging studies Bilateral cervical angiography : circumscribing Vessels also correlating strongly with PTA

Dr Ahmed Esawy

Parathyroid Adenoma FNAB • role of FNA for Dx • don’t do it! • single vessel enters the end of the gland,

easily damaged at biopsy • induces fibrosis/necrosis which can make

resection more difficult and mimic cancer at pathology

Dr Ahmed Esawy

There is only ONE way to treat parathyroid problems--Surgery. Mini-Surgery is now available that almost everyone can/should have. You should educate yourself about the new surgical treatments available. Do not have an "exploratory" operation to find the bad parathyroid tumor--this old fashioned operation is too big and dangerous.

Dr Ahmed Esawy

parathyroid hyperplasia

Dr Ahmed Esawy

WHAT DOES IT MEAN IF THERE ARE MUTIPLE NODULES? Multiglandular disease: if more than one gland is enlarged the condition is parathyroid hyperplasia. Anatomo-pathologically is not possible to distinguish between adenoma and hyperplasia. The concept of "multiple adenoma" is controversial and generally not accepted.

Dr Ahmed Esawy

Multiple nodules: if more than one gland is enlarged the condition is parthyroid hyperplasia. Anatomo-pathologically is not possible to distinguish between adenoma and hyperplasia.

Dr Ahmed Esawy

Dr Ahmed Esawy

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Dr Ahmed Esawy

15-year-old girl with hyperparathyroidism due to parathyroid hyperplasia. A–D, Sonograms show four slightly enlarged parathyroid glands (arrows): right superior (A), right inferior (B), left superior (C), and left inferior (D). Patient subsequently underwent four-gland exploration and subtotal parathyroidectomy, leaving portion of right superior gland. Largest of resected hyperplastic glands weighed only 322 mg. Relatively small size of typical hyperplastic glands decreases sensitivity of sonography.

Dr Ahmed Esawy

Parathyroid Hyperplasia Dr Ahmed Esawy

Parathyroid Hyperplasia Dr Ahmed Esawy

76-year-old woman with left juxta-thyroid parathyroid hyperplasia. A, Arterial phase image shows the hyperenhancing parathyroid lesion (arrow), which has higher attenuation than the adjacent thyroid gland (arrowhead). B, Venous phase image shows decreased attenuation of the parathyroid lesion (arrow), representing rapid washout of contrast. The adjacent thyroid gland (arrowhead) has higher attenuation than during the arterial phase.

Dr Ahmed Esawy

WHAT IS THE VALUE OF THE MIBI SCINTIGRAPHY IF POSITIVE? WHAT IS THE VALUE IF NEGATIVE? MIBI Scintigraphy consists of an early stage (10-15 minutes) and a late stage (2-3 hours). Adenomatous/hyperplastic tissue presents uptake of Tc-99m which persists at late stage. It has a sensitivity of 88% similar to the ultrasound to detect solitary parathyroid adenomas. Its sensitivity is slightly higher than ultrasound in parathyroid hyperplasia. The main advantage over ultrasound is the detection of ectopic glands in mediastinum

Dr Ahmed Esawy

Parathyroid Hyperplasia

Dr Ahmed Esawy

FALSE NEGATIVE -Multiglandular disease: parathyroid hyperplasia -Some lesions have an early wash-out: uptake in the early stage but not late.

Dr Ahmed Esawy

Scintigraphic: false negative Dr Ahmed Esawy

Dr Ahmed Esawy

FALSE POSITIVE: -The most frequent are thyroid nodules (follicular adenomas, colloid nodules,carcinomas…) -Lymph node, remnant thymic, ectopic thyroid tissue...

Dr Ahmed Esawy

Scintigraphic: false positive Dr Ahmed Esawy

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Nuclear imaging

Dr Ahmed Esawy

Dr Ahmed Esawy

Parathyroid Imaging and Localization Using SPECT/CT

Dr Ahmed Esawy

Early phase (A) and delayed phase (B) of planar 99mTc-sestamibi scan showing normal parathyroid findings

Dr Ahmed Esawy

Intravenous injection of 25mCi of 99mTechnetium •AP and oblique views of thorax and neck with gamma camera immediately after injection and at 1h and 4h or SPECT (single photon emission computed tomography) •Limitations with coexistence of thyroid pathology or other metabolically active tissue can be overcome with double-tracer subtraction technique

Dr Ahmed Esawy

Dr Ahmed Esawy

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the clinical value of SPECT/CT in the management of parathyroid patients. Using SPECT/CT requires additional imaging time and, therefore, appropriate planning and organization Using SPECT/CT has improved the overall accuracy rates of parathyroid examination

Dr Ahmed Esawy

(A) SPECT/CT image showing possible adenoma, but thyroid uptake creates difficulty. (B) Misregistration, which may have resulted from patient movement between SPECT and CT acquisitions. This study was subsequently reprocessed.

Dr Ahmed Esawy

Adenoma in left inferior gland, visible in delayed phase of planar 99mTc-sestamibi scan.

Dr Ahmed Esawy

Early phase (A) and delayed phase (B) of planar 99mTc-sestamibi scan showing high uptake in parathyroid, consistent with adenoma

Dr Ahmed Esawy

Transverse (A), fused coronal (B), and fused sagittal (C) SPECT/CT images showing higher uptake in neck,consistent with parathyroid adenoma, which helped to support information given by planar scan.

Dr Ahmed Esawy

SPECT/CT coronal(A) and transverse (B) images that helped to confirm position of adenoma. Both images show high-uptake area consistent with parathyroid adenoma.

Early phase (A) and delayed phase (B) of planar 99mTc-sestamibi scan showing high-uptake area on left side of neck consistent with parathyroid adenoma

Dr Ahmed Esawy

Early phase (A) and delayed phase (B) of planar 99mTc-sestamibi scan showing irregular uptake within thyroid gland.

Dr Ahmed Esawy

Coronal (A),transverse (B), and sagittal (C)SPECT/CT images showing uptake within neck area. Even though fused images helped with anatomic localization,disease within parathyroid gland could not be excluded

Dr Ahmed Esawy

Planar 99mTcsestamibi scan showing uneven thyroid uptake on 600-s anterior view. Scan was acquired 20 min after injection.

Dr Ahmed Esawy

Parathyroid Imaging - Tc-99m Sestamibi

45 min Anterior 45 min LAO

2 HR 2 HR

submandibular gland

thyroid lobe

adenoma

Delayed views

Dr Ahmed Esawy

Right inferior pole parathyroid adenoma

15 min Ant 1 hr Ant 1 hr RAO

adenoma Dr Ahmed Esawy

15 min Ant 1 hr Ant

Right superior parathyroid adenoma

adenoma Dr Ahmed Esawy

Right inferior parathyroid adenoma - 54F

15 min Ant 1 hr Ant 1 hr RAO

adenoma Dr Ahmed Esawy

Tc-99m sestamibi positive for intense uptake LIP

Immed Ant Delay Ant

Dr Ahmed Esawy

preoperative localization is cost effective by reducing in patient stay and reducing the incidence of complications. It is also likely that this will improve the patient experience for this procedure. We favor subtraction imaging with the support of high-resolution ultrasound for optimum preoperative localization

Dr Ahmed Esawy

Two patient studies using subtraction imaging and pinhole collimator. The first patient (A) has a normal iodine scan. The sestamibi scan demonstrates an abnormal area of accumulation at the lower pole of the right lobe of the thyroid, without the need for subtraction. The subtraction scan confirms this site of abnormality. The second patient (B) has an ectopic gland below the left lobe of the thyroid.

Dr Ahmed Esawy

The patient has a normal iodine scan. The subtraction image allows the localization of the parathyroid adenoma to be made with greater confidence than on the sestamibi scan alone

Dr Ahmed Esawy

The iodine scan demonstrates a multinodular thyroid. The subtraction scan shows increased uptake of sestamibi in the right lobe of the thyroid within the upper and lower poles, corresponding to 2 adenomas.

Dr Ahmed Esawy

The iodine scan has a normal appearance. The sestamibi subtraction scan demonstrates 3 abnormal areas of uptake, 2 in the right lobe of the thyroid and 1 below the left lobe. The patient had four gland hyperplasia, the upper pole of the left lobe was missed

Dr Ahmed Esawy

99mTc-sestamibi images viewed at 20 minutes and 2 hours after injection of sestamibi (dual-phase technique) using pinhole collimation. The early image on the left shows the distribution of sestamibi in the thyroid and parathyroid tissue, with a small area of slight increased uptake seen at the lower pole of the right lobe of the thyroid. This is seen more clearly at 2 hours when the thyroid activity has “washed out.”

Dr Ahmed Esawy

Parathyroid Carcinoma Rare (<1%) of enlarged parathyroids Clues: peroperative Ca++ and PTH extremely

high – nonspecific Local invasion at surgery Dx: external path or metastases (up to 30% at

presentation)

Dr Ahmed Esawy

Dr Ahmed Esawy

In some settings biopsies are performed of the parathyroid glands. The latter may be used to confirm that the tissue identified is actually parathyroid tissue through staining for parathyroid hormone (PTH).

None except local irritation by scanning. If biopsies are performed, pain, bleeding, and infection may be seen in rare cases.

Dr Ahmed Esawy

Clinical Features Associated with Malignancy in Parathyroid Neoplasms • Serum calcium level >14 mg/dl • Serum parathormone levels 2 to 3 times normal • Severe metabolic manifestations: nephrolithiasis, bone disease, etc. • Palpable neck mass • Difficulty in surgical dissection owing to adherence to surrounding structures

Dr Ahmed Esawy

Parathyroid carcinoma.

Radiology Imaging procedures are of similar utility as in parathyroid adenomas

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

Parathyroid carcinoma in a patient with severe hyperparathyroidism. A, Axial T2-weighted MR image shows a demarcated 2.5-cm mediastinal mass (*) that represents a parathyroid carcinoma. B, Axial T2-weighted MR image of another patient with hypercalcemia shows a nonhomogeneous mass in the right tracheoesophageal groove. The margins are slightly unsharp. This is a parathyroid carcinoma. C, Axial T2-weighted MR image shows a large mass in the right tracheoesophageal groove in this patient with severe hypercalcemia. At surgery, this was a parathyroid carcinoma Dr Ahmed Esawy

SECONDARY NEOPLASMS

Definition: Contiguous involvement from tumors in adjacent structures or metastatic neoplasms from distant sites involving the parathyroid gland.

Dr Ahmed Esawy

Dr Ahmed Esawy

Hypoparathyroidism

Dr Ahmed Esawy

Hypoparathyroidism is decreased function of the parathyroid glands with underproduction of parathyroid hormone. This can lead to low levels of calcium in the blood,

Dr Ahmed Esawy

Causes of Hypoparathyroidism

►Acquired

►Idiopathic / Inherited

Dr Ahmed Esawy

CAUSES OF ACQUIRED HYPOPARATHYRIODISM

Surgical hypoparathyroidism Removal of, or trauma to, the parathyroid glands due to thyroid surgery (thyroidectomy), parathyroid surgery (parathyroidectomy) or other surgical interventions in the central part of the neck Autoimmune invasion and destruction is the most common non-surgical cause. It can occur as part of autoimmune polyendocrine syndromes. Hemochromatosis Magnesium deficiency

Dr Ahmed Esawy

IDIOPATHIC HYPOPARATHYROIDISM

A form occuring at an early age (genetic origin) with autosomal recessive mode of transmission “multiple endocrine deficiency –autoimmune-candidiasis (MEDAC) syndrome” “Juvenile familial endocrinopathy” “Hypoparathyroidism – Addisson’s disease – mucocutaneous candidiasis (HAM) syndrome

Idiopathic (of unknown cause), occasionally familial (e.g. Barakat syndrome (HDR syndrome) a genetic development disorder resulting in hypoparathyroidism, sensorineural deafness and renal disease)

Absence or dysfunction of the parathyroid glands is one of the components of chromosome 22q11 microdeletion syndrome (other names: DiGeorge syndrome, Schprintzen syndrome, velocardiofacial syndrome). Circulating antibodies for the parathyroid glands and the adrenals are frequently present. Other associated disease:

Pernicious anemia Ovarian failure Autoimmune thyroiditis Diabetes mellitus

DiGeorge syndrome, a disease in which hypoparathyroidism can occur due to a total absence of the

parathyroid glands at birth. Familial hypoparathyroidism occurs with other endocrine diseases, such as adrenal insufficiency, in a syndrome called autoimmune polyglandular failure syndrome type 1 (APS-I).

A defect in the calcium receptor leads to a rare congenital form of the disease Dr Ahmed Esawy

Radiographic features musculoskeletal

focal (25%) and generalised (10%) Osteosclerosis pelvis, inner table of the skull, prox. femur, v.bodies. dense metaphyseal bands skull vault thickening diffuse idiopathic skeletal hyperostosis-like changes subcutaneous periarticular calcification (around shoulders and hips)

CNS

intracranial calcifications: most commonly basal ganglia but also subcortical white matter, corona radiata and thalamus, cerebrum & cerebellum

head and neck

cataract

Dr Ahmed Esawy

Markers parathyroid hormone (PTH) level: low serum phosphate level: high serum calcium level: low

Dr Ahmed Esawy

dense metaphyseal bands Dr Ahmed Esawy

dense metaphyseal bands Dr Ahmed Esawy

Dr Ahmed Esawy

diffuse idiopathic skeletal hyperostosis Dr Ahmed Esawy

diffuse idiopathic skeletal hyperostosis

Dr Ahmed Esawy

cataract

Dr Ahmed Esawy

Pseudo hypoparathryoidism Pseudohypoparathyroidism (normal PTH levels but tissue insensitivity to the hormone, associated with mental retardation and skeletal deformities) - Hereditary, dominant. Ccc by hypocalcemia & hyperphosphatemia not responding to parathormone End-organ resistance ??, defective cAMP in kidney and bone. Radiological features: as above.

1. Short stature, large skull. 2. Short metacarpals, metatarsal & phalanges esp. 4th and 5th metacarpals. 3. Teeth hypoplasia & defective enamel. 4. Basal gang., cerebellum & skin calcification by CT. 5. Deformities (chr. tetany): Coxa vara, valga Cone shaped epiph. Bowing of bones.

Pseudo pseudo hypoparahyroidism - Same skeletal manifestations of pseudohypoparathyroid but with normal blood

chemistry. Dr Ahmed Esawy

brain showed calcification in the basal ganglia, thalamus and cerebral white matter

Dr Ahmed Esawy

Short metacarpals, metatarsal & phalanges esp. 4th and 5th metacarpals Dr Ahmed Esawy

Patients with pseudopseudohypoparathyroidism have similar clinical and radiological features as pseudohypoparathyroidism but without alterations in parathyroid hormone levels and calcium metabolism. There is often a family history of pseudohypoparathyroidism

Pseudohypoparathyroidism (PHP) is a condition where there is end-organ resistance to parathyroid hormone / parathormone (PTH).

Dr Ahmed Esawy

bilateral basal ganglia and subcortical calcification. Dr Ahmed Esawy

Brain CT scan shows bilateral calcification in basal ganglia, periventricular demyelination and mild dilatation of lateral ventricles

Dr Ahmed Esawy

T2-weighted views of brain MRI shows high-intencity signals in periventricular white matter and midbrain

Dr Ahmed Esawy

THANK YOU

Dr Ahmed Esawy

Dr Ahmed Esawy

Dr Ahmed Esawy

GIOTRE

DIFFUSE FOCAL/NODULAR

MULTINODULAR UNINODULAR

NON-TOXIC TOXIC

Structural / Anatomy

Functional /biochemical

Dr Ahmed Esawy

NODULAR GIOTRE

UNINODULAR

MULTINODULAR MNG

INACTIVE

COLD

TOXIC NODULE

TOXIC NODULE

TOXIC MULTINODULAR GIOTRE INACTIVE

COLD

MALIGNANT BENIGN Dr Ahmed Esawy

NODULAR GIOTRE

BENIGN ADENOMA NEOPLASM COLLIOD

Cyst Complex cyst

Focal thyrioditis

MALIGNANT

As function: biochemical - hot (toxic) - cold (N :TSH) cold nodule in a toxic thyroid (as may

occur in Grave’s disease) Dr Ahmed Esawy

Parathyroid adenoma detected by 201Tl/99mTc-pertechnetate subtraction imaging (A to C) and by 99mTc-sestamibi subtraction imaging with 123I (D). A, 99mTc-pertechnetate concentrated within the thyroid gland. B, 201Tl concentrated within thyroid and parathyroid glands. C, Computer techniques allow technetium concentrated in the thyroid gland to be subtracted from thallium that accumulates within thyroid and parathyroid tissue. After thyroid subtraction, a parathyroid adenoma is noted as a focus of increased thallium uptake (arrows). D, 99mTc-sestamibi subtraction imaging with 123I shows an adenoma below the inferior pole of the left lobe of the thyroid gland

Dr Ahmed Esawy