Cocaine was first isolated from the leaves in 1860.Globally, in 2019, cocaine was used by an estimated 20 million people (0.4% of adults aged 15 to 64 years). The highest prevalence of cocaine use was in Australia and New Zealand (2.1%), followed by North America (2.1%), Western and Central Europe (1.4%), and South and Central America (1.0%). Since 1961, the international Single Convention on Narcotic Drugs has required countries to make recreational use of cocaine a crime. In the United States, cocaine is regulated as a Schedule II drug under the Controlled Substances Act, meaning that it has a high potential for abuse and has an accepted medical use for treatment. While rarely used medically today, its accepted uses are as a topical local anesthetic for the upper respiratory tract as well as to reduce bleeding in the mouth, throat and nasal cavities. Medical
Topical cocaine is sometimes used as a local numbing agent and vasoconstrictor to help control pain and bleeding with surgery of the nose, mouth, throat or lacrimal duct. Although some absorption and systemic effects may occur, the use of cocaine as a topical anesthetic and vasoconstrictor is generally safe, rarely causing cardiovascular toxicity, glaucoma, and pupil dilation.
Non-perfused elements of other types of vascular rings (e.g. left arch with atretic (closed) end) or the ligamentum arteriosum might be difficult to visualize by echocardiography. Computed tomography (CT):
Computed tomography after application of contrast media is usually diagnostically accurate. It shows the relationship of the arches to the trachea and bronchi. Magnetic resonance imaging (MRI):
Magnetic resonance imaging provides excellent images of the trachea and surrounding vascular structures and has the advantage of not using radiation for imaging compared to Computed tomography. Cardiac catherization/aortography:
Today patients with double aortic arch usually only undergo cardiac catherization to evaluate the hemodynamics and anatomy of associated congenital cardiac defects. Through a catheter in the ascending aorta contrast media is injected and the resulting aortography may be used to delineate the anatomy of the double aortic arch including sites of narrowing in the left aortic arch. Aortography can also be used to visualize the origin of all head and arm vessels originating from the two arches. Classification
Double aortic arch is a subtype of complete vascular ring. There are three types of double aortic arch:

Right dominant arch (about 70% of surgical cases)
Balanced or codominant (about 5%): both arches are of equal size
Left dominant (about 25%)Double aortic arch with right dominant arch:
Normally there is only one (left) aortic arch. In patients with double aortic arch the ascending aorta arises normally from the left ventricle but then divides into two arches, a left and a right aortic arch which join posteriorly to become the descending aorta.