Examination of Pathology Demonstration of Thyroid Nodules And the Post Thyroidectomy Neck

Normal Sonographic Appearance of the Thyroid The normal thyroid will appear as a: – Uniformly echogenic gland – With medium to high level echoes – More echogenic then the surrounding anatomy – An echogenic band (specular reflector) surrounds the margins of both lobes and the isthmus (Curry and Tempkin 2011, 442) (Rumack et.al. 2011, 710)

Identification of Nodules with Ultrasound Ultrasound is the most commonly used imaging technique for the localisation and interrogation of nodular thyroid disease. Although thyroid nodules are very common, few carry malignant potential. These malignant nodules however need to be identified to ensure that these patients receive proper treatment. (Rumack et.al. 2011, 710)

Benign vs. Malignant Nodules – Ultrasound Appearance Benign nodules: – Are well defined – Often cystic – Hyperechoic to adjacent anatomy – May have peripheral egg-shell calcification – Display peripheral flow on Colour and power Doppler Malignant nodules – Solid – Hypoechoic to adjacent anatomy – May display a wide irregular halo surrounding the nodule – May contain fine puncate internal calcifications – Marked internal hyper - vascularity. (Henningson 2004, )

Thyroid Nodules The following is a series of images of a patient with multiple thyroid nodules. Measurements have been made of the more prominent nodules.

Image 1 – Comparison image displaying both lobes of the thyroid gland and the isthmus. Note the general heterogeneity of the gland and the presence of nodules in both lobes.

Transverse Images The following are transverse images of the left and right lobes display the numerous nature of these nodules as well as the differing appearances.

Images 1 – 4 : Callipers demonstrate nodules within the generally heterogenous right lobe of the thyroid.

Images 5 – 8 : Callipers demonstrate nodules within the generally heterogenous left lobe of the thyroid. Images are of the same patient seen in images 1-4.

Longitudinal Images The following are longitudinal images of the left and right lobes display the numerous nature of these nodules as well as the differing appearances.

Images 9 – 10: Demonstrate the extent of nodularity in the right lobe. Callipers in Image 10 display further the extent of the previously seen nodules.

Images 11 – 14: Callipers demonstrate nodules within the generally heterogenous left lobe of the thyroid.

Colour Doppler Imaging Is performed in both planes for both lobes. Images for the right lobe are shown here.

Images : Colour and Power Doppler imaging of the right lobe in transverse and longitudinal planes.

Examination of the Anterior Triangles Normal protocol requires imaging of each anterior triangle.

Images : Transverse imaging of the right and left anterior triangles, respectively. Note the absence of any abnormal lymph nodes.

Reported Findings The report for this examination did not identify any lesion of immediate concern but did suggest follow up examination in 6 – 12 months. In addition to this, the comment was made that if concern still existed that one or more of the nodules could be biopsied for further reassurance. At present biopsy has not been arranged.

Interventional Procedures When a nodule or lymph node of concern is identified fine needle aspiration or biopsy may be used to aid in the diagnosis. These procedures are most commonly done under ultrasound guidance but can however also be performed by palpating the nodule. In cases where malignancy is found thyroidectomy is the most common form of intervention. (Curry and Tempkin 2011, 454)

Post Thyroidectomy The following images are of a patient post complete thyroidectomy. Care is taken to examine the region thoroughly in case of recurrence in remanent tissue or cervical lymph nodes.

Images 21 – 22: Transverse and longitudinal images of the neck post thyroidectomy. These images represent the right and left neck respectively.

Images 25 – 26: Transverse images of the anterior triangles post thyroidectomy. These images represent the right and left respectively. No abnormal LN’s were seen in this study.

Reported Findings On this examination there was no evidence of reoccurrence or new lymphatic involvement.

Alternative Imaging Other forms of imaging which may aid in the diagnosis and treatment of thyroid nodules includes – Scintigraphy – PET – CT – MRI Practitioners may also find it helpful to compare these result with thyroid function blood tests. (Curry and Tempkin 2011, 454)

References Curry, R.A., and B.B. Tempkin Sonography: introduction to Normal structure and Function. 3 rd ed. Missouri: Elsevier Saunders. Henningson, C Clinical Guide to Ultrasonography. St Louis, Missouri: Mosby. Rumack, C.M., S.R. Wilson, J.W. Charboneau, and D. Levine Diagnostic Ultrasound. 4 th ed. Philadelphia: Elsevier Mosby.