Abstract

Background: When the right subclavian artery directly arises from the arch of aorta (AOA) distal to the origin of the left subclavian artery, it is known as an aberrant right subclavian artery (ARSCA). It is a most common anomaly of AOA occurs in approximately 0.5–1.8% cases and usually remains asymptomatic. In case of ARSCA, commonly it has a retroesophageal course to reach the right side of the neck. Variations in origin and course of vertebral artery (VA) found in 7% cases, more on the left side than the right side. Objectives: To study the origin, course and branching pattern of the subclavian artery and discuss its embryology and histological changes of the variant artery.
Materials and Methods: The 67 embalmed cadavers were utilized for dissection for MBBS students at various Medical Colleges in Patna, Bihar in the Department of Anatomy. The course and branching pattern of both side subclavian arteries were observed. Histopathological observations of variant arteries were also noted.
Results: ARSCA with the retroesophageal course along with the right VA (RVA) was originating from the right common carotid artery was noted in one case. The aberrant VA traverse through the foramen th transversaria of 5 cervical vertebrae. Histopathological observation of ARSA and RVA showed atherosclerotic changes. Conclusion: The knowledge of such variation is important for carrying out surgical procedure and clinically significant during diagnostic and interventional angiographic procedures.