Figure 1
Teaching Case
SectionHead & neck imaging
Case TypeAnatomy and Functional Imaging
AuthorsDr. Elton CEKAJ
Connected authors
53 years, female
The patient presented to the hospital with anxiety and breathing difficulty. She came to our department to have an ultrasound (US) examination to evaluate the thyroid gland because the doctor noticed an asymmetry in the anterior neck. FT3, FT4 and TSH were within normal values.
Left thyroid hemiagenesis
Thyroid lobe hypoplasia
Ectopic thyroid gland
Thyroid lobectomy
Ultrasound (US) showed absence of the left thyroid lobe with only a right lobe and isthmus present. Right lobe dimensions were 2.11 x 2.46 x 5.34 and within it there were a colloid cyst and a nodus present. The same findings were present in the isthmus as well and its anteroposterior diameter was 5 mm. US did not show signs of a pyramidal lobe, thyroglossal remnants or ectopic thyroid (Fig 1a, 1b, 1c, 1d). The missing left lobe was confirmed on MRI (axial T1W and T2W, coronal T1W and T2W) (Fig 2a, 2c, 2b, 2d) and by nuclear scintigraphy (Fig 3).
Thyroid haemiagenesis is a rare congenital abnormality, in which one of the thyroidal lobes fails to develop. The cause of thyroid haemiagenesis is unclear but is thought to result from cells migrating laterally resulting in a one-lobed thyroid gland with or without an isthmus.[1] The prevalence rate of thyroid hemiagenesis is not well-known but several studies have shown that in the normal population it is 0.05–0.2%. [2–4]
Gursoy et al. have indicated the prevalence of thyroid haemiagenesis as 0.025% in the normal population and 0.25% in patients with thyroid disorders.[5] The first known case was described in 1866 by Handsfield-Jones [6] and the first study on this subject was reported by Marshall in 1895. [7]
Thyroidal haemiagenesis is predominantly seen in females with the left lobe being absent more frequently than the right one in the ratio 4:1. [2]
Thyroidal haemiagenesis by itself is asymptomatic, so cases typically are diagnosed as an incidental finding in routine neck ultrasound for other causes. Thyroid ultrasound usually is diagnostic and other imaging methods are usually not necessary. [2, 8]
CT examination can be diagnostic but administers radiation and injection of intravenous contrast material may be given. Magnetic resonance imaging is useful as well and nuclear scintigraphy (Fig 3) demonstrates absence of uptake in the missing lobe, indicative of haemiagenesis and differentiating it from ectopic thyroidal tissue. [8]
Gursoy et al. have indicated the prevalence of thyroid haemiagenesis as 0.025% in the normal population and 0.25% in patients with thyroid disorders.[5] The first known case was described in 1866 by Handsfield-Jones [6] and the first study on this subject was reported by Marshall in 1895. [7]
Thyroidal haemiagenesis is predominantly seen in females with the left lobe being absent more frequently than the right one in the ratio 4:1. [2]
Thyroidal haemiagenesis by itself is asymptomatic, so cases typically are diagnosed as an incidental finding in routine neck ultrasound for other causes. Thyroid ultrasound usually is diagnostic and other imaging methods are usually not necessary. [2, 8]
CT examination can be diagnostic but administers radiation and injection of intravenous contrast material may be given. Magnetic resonance imaging is useful as well and nuclear scintigraphy (Fig 3) demonstrates absence of uptake in the missing lobe, indicative of haemiagenesis and differentiating it from ectopic thyroidal tissue. [8]
References
[1] Greening WP, Sarker SK, Osborne MP (1980) Hemiagenesis of the thyroid gland. Br J Surg 67 (6): 446–448 (PMID: 7388347)
[2] Shabana W, Delange F, Freson M, Osteaux M, de Schepper J. (2000) Prevalence of thyroid hemiagenesis: ultrasound screening in normal children. Eur J Pediatr 159:456–8 (PMID: 10867854)
[3] Maiorana R, Carta A, Floriddia G, et al (2003) Thyroid hemiagenesis: prevalence in normal children and effect on thyroid function. J Clin Endocrinol Metab 88:1534–6 (PMID: 12679435)
[4] Korpal-Szczyrska M, Kosiak W, Swieton D (2008) Prevalence of thyroid hemiagenesis in an asymptomatic schoolchildren population. Thyroid 18:637–9 (PMID: 18578613)
[5] Gursoy A, Anil C, Unal AD, Demirer AN, Tutuncu NB, Erdogan MF (2008) Clinical and epidemiological characteristics of thyroid hemiagenesis: ultrasound screening in patients with thyroid disease and normal population. Endocrine 18 (PMID: 19016002)
[6] Handfield-Jones (1896) Handbuch der Systematischen Anatomie des Menschen. Friedrich Vleiwig und Braunschweig, Sohn
[7] Marshall CF (1895) Variations in the form of thyroid gland in man. J Anat Physiol 29: 234-237 (PMID: 17232125)
[8] De Remigis P, D\'Angelo M, Bonaduce S, et al (1985) Comparison of ultrasonic scanning and scintiscanning in the evaluation of thyroid hemiagenesis. J Clin Ultrasound 13: 561-3 (PMID: 3934219)
Case information
| URL: | https://www.eurorad.org/case/10421 |
| DOI: | 10.1594/EURORAD/CASE.10421 |
| ISSN: | 1563-4086 |
Figure 2
Qendra Diagnostike \"MEDICARE\", Tirane, Albania
