Pyramidal lobe of thyroid
Citation, DOI, disclosures and article data
Citation:
Khader.O.Thabet M, Knipe H, Weerakkody Y, et al. Pyramidal lobe of thyroid. Reference article, Radiopaedia.org (Accessed on 13 Mar 2025) https://doi.org/10.53347/rID-36922
rID:
36922
Article created:
18 May 2015,
Mohammed Al Khader.O.Thabet
Disclosures:
At the time the article was created Mohammed Al Khader.O.Thabet had no recorded disclosures.
View Mohammed Al Khader.O.Thabet's current disclosures
Last revised:
Disclosures:
At the time the article was last revised Henry Knipe had the following disclosures:
- Micro-X Ltd, Shareholder (past)
These were assessed during peer review and were determined to not be relevant to the changes that were made.
View Henry Knipe's current disclosures
Revisions:
20 times, by
12 contributors -
see full revision history and disclosures
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Synonyms:
- Pyramidal lobe of the thyroid gland
- Pyramidal lobe of the thyroid
- Pyramidal lobe of thyroid gland
- Lalouette's pyramid
- Lalouette pyramid
- Pyramidal lobe of thyroid
The pyramidal lobe of the thyroid, also known as Lalouette pyramid 5, is a normal anatomic variant representing a superior projection of thyroid parenchyma arising from the thyroid isthmus.
On this page:
Epidemiology
A pyramidal lobe is present in ~20 (range 10-30%) of the population ref and is commonly seen on routine thyroid ultrasound 3.
Gross anatomy
The pyramidal lobe is seen as a third thyroid lobe and represents a persistent remnant of the thyroglossal duct. It usually arises from the right or left side of the isthmus extending in a cranial direction; pyramidal lobes arising directly from the midline of the isthmus are rare (~2%) 3.
A band of fibrous tissue may be present extending superiorly from the pyramidal lobe to the hyoid bone, sometimes with a skeletal muscle component, termed the levator glandulae thyroideae muscle 4.
Clinical importance
The pathologies seen in the remainder of thyroid can also seen in the pyramidal lobe ref.
References
- 1. Anil T. Ahuja, Rhodri M. Evans. Practical Head and Neck Ultrasound. (2000) ISBN: 9781900151993 - Google Books
- 2. Wolfgang Dähnert. Radiology Review Manual. (2011) ISBN: 9781609139438 - Google Books
- 3. Mortensen C, Lockyer H, Loveday E. The Incidence and Morphological Features of Pyramidal Lobe on Thyroid Ultrasound. Ultrasound. 2014;22(4):192-8. doi:10.1177/1742271X14554677 - Pubmed
- 4. Chaudhary P, Singh Z, Khullar M, Arora K. Levator Glandulae Thyroideae, a Fibromusculoglandular Band with Absence of Pyramidal Lobe and Its Innervation: A Case Report. J Clin Diagn Res. 2013;7(7):1421-4. doi:10.7860/JCDR/2013/6144.3186 - Pubmed
- 5. Germano A, Schmitt W, Carvalho M, Marques R. Normal Ultrasound Anatomy and Common Anatomical Variants of the Thyroid Gland Plus Adjacent Structures - A Pictorial Review. Clin Imaging. 2019;58:114-28. doi:10.1016/j.clinimag.2019.07.002 - Pubmed
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