Identify the anatomical structure indicated by the blue arrow in the image below.

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Options:
explanation: The image shows a posterior view of the lungs and the trachea. The right upper lobe is the most superior lobe of the right lung. However, the structure indicated by the arrow is the middle lobe of the right lung, which is situated between the superior and inferior lobe. The right lung has three lobes (superior, middle and inferior), separated by 2 fissures (horizontal and oblique). All these structures can be seen on the image – the right lung is located on the right side of the image. The fact that this is a posterior view of the lungs can also be inferred from the ability to view the epiglottis, and not the thyroid or cricoid cartilages at the top of the trachea.
name: Right upper lobe
label: b
answer: no
explanation: The image shows a posterior view of the lungs and the trachea. The right lower lobe is the most inferior lobe of the right lung. However, the structure indicated by the arrow is the middle lobe of the right lung. The right lung has three lobes (superior, middle and inferior), separated by two fissures (horizontal and oblique). All these structures can be seen on the image – the right lung is located on the right side of the image. The fact that this is a posterior view of the lungs can also be inferred from the ability to view the epiglottis, and not the thyroid or cricoid cartilages at the top of the trachea.
name: Right lower lobe
label: c
answer: no
explanation: The image shows a posterior view of the lungs and the trachea. The left lower lobe is the inferior lobe of the left lung. However, the structure indicated by the arrow is the middle lobe of the right lung. The right lung has three lobes (superior, middle and inferior), separated by two fissures (horizontal and oblique). All these structures can be seen on the image. The right lung is located on the right side of the image and the left lung is on the left side of the image. The fact that this is a posterior view of the lungs can also be inferred from the ability to view the epiglottis, and not the thyroid or cricoid cartilages at the top of the trachea.
name: Left lower lobe
label: e
answer: no
explanation: The image shows a posterior view of the lungs and the trachea. The left upper lobe is the superior lobe of the left lung. However, the structure indicated by the arrow is the middle lobe of the right lung. The right lung has three lobes (superior, middle and inferior), separated by two fissures (horizontal and oblique). All these structures can be seen on the image. The right lung is located on the right side of the image and the left lung is on the left side of the image. The fact that this is a posterior view of the lungs can also be inferred from the ability to view the epiglottis, and not the thyroid or cricoid cartilages at the top of the trachea.
name: Left upper lobe
label: d
answer: no
explanation: The image shows a posterior view of the lungs and the trachea. The structure indicated by the arrow is the middle lobe of the right lung. The right lung has three lobes (superior, middle and inferior), separated by two fissures (horizontal and oblique). All these structures can be seen on the image – the right lung is located on the right side of the image. The fact that this is a posterior view of the lungs can also be inferred from the ability to view the epiglottis, and not the thyroid or cricoid cartilages at the top of the trachea.
name: Middle lobe
label: a
answer: yes

Correct answer: a