Thyroid Ultrasound for Thyroidologists

Durr-e-Sabih

...Ultrasound allows surgeons and endocrinologists to better follow nodules, identify tumors, make decisions about surgery on the contralateral lobe, map metastatic disease and recurrence and better follow patients with treated malignancy. Ultrasound improves our selectivity of patients eligible for surgery because of improvements in sensitivity and specificity of ultrasound guided fine needle aspiration biopsy…

Summary of proceedings of the second world congress on Thyroid Cancer. July 2013. Canada

Whyo Accurate depiction of neck anatomyo Clarifies doubtful findingso Differentiates thyroid from non-thyroidal

masseso Detection of non-palpable disease o Follow-up of focal diseaseo Guides FNA/therapy o Suggests probable benign/malignant for

stratification of further workup

The section

The section

Surroundings

ThyroidTrachea

Oesophagus

Cervical VertebraC-6

CCA

Int Jug vein

Sternocleidomastoid

Sternohyoid

Sternothyroid

Longus coli

Scalenus anterior

Surroundings

Surroundings

Thyroid

Trachea

Oesophagus

Cervical VertebraC-6

CCA Int Jug vein

Sternocleidomastoid

SternohyoidSternothyroid

Longus coliScalenus anterior

Size

o Each lobe 4-6 cm in cranio-caudal extento <1.8 cm in maximum depth, isthmus <6mm

in thickness o Volume 7-14ml, calculated for each lobe

and add

4-6 cm

<1.8cm

<1.8cm

<1.8cm

<0.6cm

Size4-6 cm

Volume; 7-14 ml. Calculate for each lobe and add

Textureo Medium to high density

echoes, homogenous o Thin capsule occasionally

seen… might become calcified in uraemia

o Muscles are hypoechoic o Texture can appear different

with different equipment… use same equipment for follow-up

o Parathyroids not visible unless enlarged

My thyroid

Xario

Aplio

Nemio

Blood supply

o Superior thyroid artery and vein at the upper pole of each lobe

o Inferior thyroid vein at the lower poleo Inferior thyroid artery is posterior to the

lower third of each lobe

Superior thyroid artery

Inferior thyroid artery

Inferior thyroid vein

Sup th. vein

Mid th. vein

Inf th. vein

Int jug vein

Thyroida ima

Parenchymal vascularity

What do we look for in a thyroid nodule?Echogenicity Isoechoic, Hyperechoic

HypoechoicMarkedly hypoechoic

Same , more or less than normal areas of thyroidLess than strap muscles

Content Predominantly CysticMixed Cystic and SolidPredominantly Solid

75-100% of volume cystic26-74%0-25%

Calcification Microcalcifications (Psammoma bodies) <1mm, no shadowing

Macrocalcificaions, rim calcifications >1mm, may cause shadowing

Colloid crystals Reverberating echogenicities

Margin Smooth/irregular

Orientation Taller- than- wide/wider-than- than tall

Vascularity None, marginal, central

Nodes Shape (eliptical or round), hilum (present or absent), microcalcification or colloid

Extension beyond thyroid

1) Society of Radiologists in Ultrasound consensus conference Statement. Radiology Vol 237 (3). 2005.2) Huang JK; Lee WK; Lee M et al. US Features of Thyroid Malignancy: Pearls and Pitfalls. RadioGraphics 2007; 27:847–865

Features Feature Benign Malignant

Tall/Wide Wider than tall +++ ++

Taller than wide + ++++

Contents Purely cystic ++++ +

Cystic with thin septa +++ +

Mixed Solid/cystic +++ ++

Purely solid +++ ++

Comet tail reverberations +++ +

Echogenicity Hyperechoic ++++ +

Isoechoic +++ ++

Hypoechoic +++ +++

Markedly hypoechoic + ++++

Halo Thin ++++ ++

Thick + +++

Absent + +++

Margins Well defined +++ ++

Poorly defined ++ +++

Spiculated + ++++

Calcification Eggshell +++ ++

Coarse +++ +

Micro ++ ++++

Doppler Peripheral +++ ++

Internal flow ++ +++

Thyroid nodules

Thyroid Nodules

o Is it in the thyroid or outside it?

Hyperplastic, Adenomatous or Colloid Nodule

o Cellular hyperplasia, microndule nodule, macronodule formation

o Liquefactive degeneration with accumulation of serous fluid, blood and colloid material

o Calcification, often coarse and peripheralo Can be hypo functioning, normally

functioning or hyperfunctioning

Colloid cyst and Nodule, Haemorrhagic cyst

© Dr. Ravi Kadasne. UAE

Colloid Nodules

Follicular Neoplasm

o Follicular adenoma is a true neoplasm with compression of adjacent tissue and fibrous capsulation

o Capsular/vascular invasion is the hallmark of follicular carcinoma, that can be seen on histology and not cytology

Follicular Neoplasm

o FNA does not differentiate between benign follicular adenoma and carcinoma (capsular and vascular invasion)

o Usually solidoHypo, iso or hyperechoico Thin or thick haloo Peripheral rim of vessels, sometimes extending

inwards in spoke-wheel pattern

Follicular Neoplasm Colloid Nodule

Papillary Thyroid Cancer

o Hypoechoico Microcalcificationo Hypervascular o Cervical nodes with possible

microcalcification or cystic degeneration

Papillary Carcinoma with Nodes

Metastatic Papillary Thyroid Cancer

Papillary Carcinoma

Follicular Thyroid Carcinoma

o Similar to follicular neoplasm on ultrasound o Difficult to differentiate from follicular

neoplasm on cytology… so many advocate surgical removal of all follicular neoplasms

o Some may have very irregular margins, thick irregular halos and chaotic internal vascularity

Follicular Thyroid Carcinoma

o Hypoechoico Vascularo Minimally

irregular o Reverberating

echogenicities

Image courtesy Dr. Ravi Kadasne, Al Ain. UAEVia www.ultrasound-images.com

Other Carcinomaso Medullary

o Part of the MEN-II syndrome, tends to be multicentric or bilateral

o Similar to papillary carcinoma on ultrasoundo Calcifications tend to be coarse

o Anaplastic o Large, hypoechoic, encase or invade blood vessels and muscles

o Lymphomao In most there is pre-existing Hashimoto’s and hypothyroidism,

rapidly growing masso Extremely hypoechoic, lobulated, areas of cystic necrosis

How specific is ultrasound?

o Ji-Zhen Zhang, Bing Hu. Sonographic features of thyroid follicular carcinoma in comparison with thyroid follicular adenoma. J Ultrasound Med 2014; 33:221-227

o Ji Hyun Lee, Jung Hee Shin et al. Sonographic and cytopathologic correlation of papillary carcinoma variants. J Ultrasound Med 2015; 34:1-15

How specific is ultrasound?

o Ji-Zhen Zhang, Bing Hu. Sonographic features of thyroid follicular carcinoma in comparison with Thyroid follicular adenoma. J Ultrasound Med 2014; 33:221-227

o Ji Hyun Lee, Jung Hee Shin et al. Sonographic and cytopathologic correlation of papillary carcinoma variants. J Ultrasound Med 2015; 34:1-15 Retr

ospect

ive

Features, Scores and Patterns…Organizing the Data

ScoreStudy Score Interpretation

Adamczewski and Lewiński. Proposed algorithm for management of patients with thyroid nodules/focal lesions, based on ultrasound (US) and fine-needle aspiration biopsy (FNAB); our own experience. Thyroid Research 2013, 6:6

Retrospective. Major features: Central vascularity, microcalcificaions, taller than wide, solid, hypoechoic, irregular margins, halo (1 point). Minor features: size >3cm, irregular margin, absence of halo, solid (0.5 points). Rapid growth and abnormal nodes (3 points)

0 <4, low risk of malignancy4 <7, Intermediate risk> 7 High risk

Afshin Mohammad, Tohid Hajizadeh. Evaluation of diagnostic efficacy of ultrasound scoring system to select thyroid nodules requiring fine needle aspiration biopsy. Int J Clin Exp Med 2013;6(8):641-648

Retrospective. Hypoechogenicity, irregular margin, calcification and vascularity … if present awarded 2 points each

1 feature: 81% sensitivity.>2 features FNAB

Pu Cheng, En-Dong Chen, Hua-Min Zheng et a. Ultrasound Score to Select Subcentimeter-sized Thyroid Nodules Requiring Ultrasound-guided Fine Needle Aspiration Biopsy in Eastern China. Asian Pac J Cancer Prev, 14 (8), 4689-4692

Retrospective. Irregular shape, hypoechioc, absent capsule, calcifications, taller than wide… all with score of 1 except microcalcification with a score of 2

> 2 biopsy threshold, sensitivity of 80.3% specificity of 72.3%

PatternPattern Significance

Spongiform without hypervascularity

Benign Cyst with avascular colloid plug

Giraffe pattern (skin, not the neck)

White knight (uniform hyperechogenicity)

Red light (intense hypervascularity)

Unpredictable

Intense hypoechogenicity

Isoechogenic without halo

Isoechogenic with halo

Ring-of-fire (isoechogenic with peripheral vascularity)

Other

1. Reading CC, Charboneau JW, Hay ID, Sebo TJ. Sonography of thyroid nodules: a “classic pattern” diagnostic approach. Ultrasound Q 2005; 21:157– 165

2. John A. Bonavita, Jason Mayo, James Babb et al. Joseph Yee. Pattern Recognition of Benign Nodules at Ultrasound of the Thyroid: Which Nodules Can Be Left Alone? AJR 2009; 193:207–213.

PatternSpongiform without hypervascularityCyst with avascular colloid plug

Giraffe pattern (skin, not the neck)

White knight (uniform hyperechogenicity)

John A. Bonavita, Jason Mayo, James Babb et al. Joseph Yee. Pattern Recognition of Benign Nodules at Ultrasound of the Thyroid: Which Nodules Can Be Left Alone? AJR 2009; 193:207–213.

PatternRed light (intense hypervascularity)

Intense hypoechogenicity

Isoechogenic without halo

Isoechogenic with halo

isoechogenic with peripheral vascularity (Ring-of-fire )Other

John A. Bonavita, Jason Mayo, James Babb et al. Joseph Yee. Pattern Recognition of Benign Nodules at Ultrasound of the Thyroid: Which Nodules Can Be Left Alone? AJR 2009; 193:207–213.

What then for nodules?

Thyroid vs. extra-thyroidal YesRecurrent disease YesGuiding procedures YesBiopsy vs. observe ?YesBenign ?YesMalignant ?

Diffuse Thyroid Disease

o Hyperplasiao Thyroiditiso Graves diseaseo Colloid goitre

Thyroid Hyperplasia

o Hyperplasia of cells or acini, followed by micro and then macronodule formation

o Hyperplastic nodules can undergo liquefaction with accumulation of serous fluid, blood and colloid

Suppurative and Subacute Thryoiditis

o Suppurative thyroiditis is very rare and a typical abscess is seen.

o Subacute granulomatous thyroiditis (De Quervain’s disease)oHypoechoic, diffusely or focallyoDecreased flow in involved area, normal flow

in uninvolved areas

http://www.thyroidmanager.org/chapter/ultrasonography-of-the-thyroid/#toc-sonography-in-the-patient-with-an-enlarged-thyroid-gland-goiter

Ultrasound Surprises

Short history, painless, cold on scan, irregular, hypoechoic, vascular… underwent STT…… HP- Subacute thyroiditis

Thyroiditis on two FNAs

Hashimoto’s Thyroiditis

o Enlarged, hypoechoic, hypervascular, coarse

o Micronodular, nodules are hypoechoic, intervening bands can be echogenic.

o Very high flow to very low flow

Thyroiditis

Thyrotoxicosis

Thank you