Identify the anatomical structure indicated by the blue arrow in the image below and the thoracic compartment it belongs to
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Options:
explanation: The image shows the posterior wall of the thoracic cavity. The heart and the lungs have been removed. The middle mediastinum lies anterior to the posterior mediastinum and contains the heart and the origin of the great vessels. The descending aorta lies more posterior, within the posterior mediastinum. The descending aorta lies directly anterior to the vertebral column (slightly to its left).
name: Descending aorta – middle mediastinum
label: c
answer: no
explanation: The image shows the posterior wall of the thoracic cavity. The heart and the lungs have been removed. The inferior vena cava is one of the structures contained within the posterior mediastinum. However, it is located to the right of the vertebral column, and to the right of the structure indicated by the blue arrow, which is the descending aorta. The descending aorta is located directly anteriorly to the vertebral column (slightly to its left), and is also contained within the posterior mediastinum.
name: Inferior vena cava – posterior mediastinum
label: d
answer: no
explanation: The image shows the posterior wall of the thoracic cavity. The heart and the lungs have been removed. The ascending aorta has a close anatomical relationship with the heart, emerging from its left ventricle superiorly, and thus, being contained within the same thoracic compartment – the middle mediastinum. The superior mediastinum contains the great vessels arising from/draining into the heart – the arch of the aorta and its 3 main branches and the superior vena cava and its tributaries. The superior mediastinum also contains the right and left vagus nerve, and the phrenic nerve.The arrow in the image indicates the descending aorta, which is located close to the posterior wall of the thorax, and contained within the posterior mediastinum.
name: Ascending aorta – superior mediastinum
label: b
answer: no
explanation: The image shows the posterior wall of the thoracic cavity. The heart and the lungs have been removed. The descending aorta lies directly anterior to the vertebral column (slightly to its left), so it is located close to the posterior wall of the thorax, and contained within the posterior mediastinum.
name: Descending aorta – posterior mediastinum
label: a
answer: yes
explanation: The image shows the posterior wall of the thoracic cavity. The heart and the lungs have been removed. The superior mediastinum is the most superior compartment within the mediastinum, and contains the great vessels arising from/draining into the heart – the arch of the aorta and its 3 main branches and the superior vena cava and its tributaries. The superior mediastinum also contains the right and left vagus nerve, and the phrenic nerve. The inferior vena cava lies more inferiorly, is contained within the posterior mediastinum, and not the superior mediastinum. It is located to the right of the vertebral column, and to the right of the structure indicated by the blue arrow, which is the descending aorta.
name: Inferior vena cava – superior mediastinum
label: e
answer: no

Correct answer: a