What is pyramidal lobe of thyroid gland?

The pyramidal lobe represents the inferior part of the thyroglossal duct and is considered as a normal component of the thyroid gland [1,4]. The persistence of an elongated lower portion of the thyroglossal part increases the volume (size) of the pyramidal lobe.

Where is the pyramidal lobe of thyroid gland?

The pyramidal lobe is a thyroid tissue of embryologic origin. It is situated in the pretracheal region between the isthmus and the hyoid bone.

What gland lobes are connected by an isthmus?

The right and left lobes of the thyroid gland are connected by an isthmus. The isthmus lies at the level of the second and third tracheal rings. Occasionaly, the isthmus may be absent.

How is the pyramidal lobe formed?

It 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 were rare in a large ultrasound study, accounting for only 2% of the cases 3.

What percentage of people have a pyramidal lobe?

The pyramidal lobe, representing the lower part of thyroglossal duct, varies in shape and position as well as appearance and size. It may be attached to the thyroid cartilage by fibrous tissue. The percentage of occurrence of pyramidal lobe in the literature ranges from 12 to 80%, with a median value of 61% [3].

What is an isthmus example?

One of the most famous examples of the isthmus landform is the Isthmus of Panama. The Panama isthmus is a narrow strip of land that connects Costa Rica and Colombia. Essentially, the Isthmus of Panama connects North and South America. It is bordered by the Caribbean Sea and the Pacific Ocean.

When assessing the thyroid gland you locate the isthmus where is the isthmus located?

Standing behind the patient, attempt to locate the thyroid isthmus by palpating between the cricoid cartilage and the suprasternal notch. Move your hands laterally to try to feel under the sternocleidomstoids for the fullness of the thyroid.

What connects the 2 lobes of the thyroid gland?

The thyroid gland is divided into two lobes that are connected by the isthmus, which crosses the midline of the upper trachea at the second and third tracheal rings.

How big is the pyramidal lobe of the thyroid gland?

Pyramidal Lobe of Thyroid Gland Anatomy. The structure is generally located on the left side of the thyroid gland and it measures around 10.83 mm in length and 5.50 mm in breadth. The thickness of the lobe ranges from 3-3.27 mm.

Where is the Isthmus of the thyroid gland located?

The structure indicated is the isthmus of the thyroid gland. The thyroid gland sits anteriorly in the neck, just inferior to the thyroid cartilage. It is located deep to the overlying strap muscles (sternohyoid, sternothyroid and omohyoid). It has two lateral lobes connected in the centre by the isthmus.

Why is the pyramidal lobe removed in thyroidectomy?

Pyramidal Lobe of Thyroid Gland Function. While conducting thyroidectomy for Graves’ disorder, it is mandatory to find out the location of the pyramidal lobe and remove it. This is due to the fact that the pyramidal lobe can be the actual cause of frequent hyperthyroidism leading to unfinished surgical operation of the gland.

What is the levator glandulae thyroideae?

In a few cases, the levator glandulae thyroideae is present and it stretches from the upper part of the pyramidal lobe to the hyoid bone. It is the third lobe of the thyroid gland in the thyroglossal tract.