Joll's Triangle
Joll's triangle is used to identify the location of external branch of superior laryngeal nerve during thyroid surgeries. Damage to this nerve during the surgical procedure may reduce the voice range in these patients. This triangle is also known as sternothyrolaryngeal triangle.
Boundaries:
Lateral - Upper pole of thyroid gland and superior thyroid vessels
Superior - Attachment of the strap muscles and deep investing layer of fascia to the hyoid
Medial - Midline
Floor - Cricothyroid muscle
External branch of superior laryngeal nerve lies within this triangle.