Which of the following statements correctly describes the function of the anatomical structure indicated by the arrow in the image below?
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Options:
explanation: The image shows a graphic depiction of the orbit with the periorbital fat in situ and the extraocular muscles present within the fat layer. The lateral aspect of the orbit is located to the left of the image, while the medial aspect of the orbit is found to the right of the image. The muscle indicated by the blue arrow is the superior oblique muscle, which lies medial to the superior rectus muscle and the levator palpebrae superioris muscle (which can be seen lateral to the one indicated). The function of the superior oblique muscle, which is innervated by the trochlear nerve (CN IV) is to internally rotate the eyeball.
name: Internal rotation of the eyeball
label: a
answer: yes
explanation: The image shows a graphic depiction of the orbit with the periorbital fat in situ and the extraocular muscles present within the fat layer. The lateral aspect of the orbit is located to the left of the image, while the medial aspect of the orbit is found to the right of the image. Eyeball elevation is a function of the superior rectus muscle, which is innervated by the oculomotor nerve (CN III), and which lies on the superior aspect of the eyeball and orbit, immediately inferior to the levator palpebrae superioris muscle (which elevates the eyelid). However, the muscle indicated by the blue arrow is the superior oblique muscle, which lies medial to the superior rectus muscle and the levator palpebrae superioris muscle (which can be seen lateral to the one indicated). The function of the superior oblique muscle, which is innervated by the trochlear nerve (CN IV), is to internally rotate the eyeball.
name: Elevation of the eyeball
label: c
answer: no
explanation: The image shows a graphic depiction of the orbit with the periorbital fat in situ and the extraocular muscles present within the fat layer. The lateral aspect of the orbit is located to the left of the image, while the medial aspect of the orbit is found to the right of the image. Eyelid elevation is a function of the levator palpebrae superioris muscle, which is innervated by the oculomotor nerve (CN III), and which lies immediately superior to the superior rectus muscle and lateral to the muscle indicated by the arrow in the image. However, the muscle indicated by the blue arrow is the superior oblique muscle, which lies medial to the superior rectus muscle and the levator palpebrae superioris muscle (which can be seen lateral to the one indicated). The function of the superior oblique muscle, which is innervated by the trochlear nerve (CN IV), is to internally rotate the eyeball.
name: Elevation of the eyelid
label: e
answer: no
explanation: The image shows a graphic depiction of the orbit with the periorbital fat in situ and the extraocular muscles present within the fat layer. The lateral aspect of the orbit is located to the left of the image, while the medial aspect of the orbit is found to the right of the image. Eyeball depression is a function of the inferior rectus muscle, which is innervated by the oculomotor nerve (CN III), and which lies on the inferior aspect of the eyeball and the orbit. However, the muscle indicated by the blue arrow is the superior oblique muscle, which lies medial to the superior rectus muscle and the levator palpebrae superioris muscle (which can be seen lateral to the one indicated). The function of the superior oblique muscle, which is innervated by the trochlear nerve (CN IV), is to internally rotate the eyeball.
name: Depression of the eyeball
label: d
answer: no
explanation: The image shows a graphic depiction of the orbit with the periorbital fat in situ and the extraocular muscles present within the fat layer. The lateral aspect of the orbit is located to the left of the image, while the medial aspect of the orbit is found to the right of the image. Eyeball abduction is a function of the lateral rectus muscle, which is innervated by the abducens nerve (CN VI), and which lies to the lateral aspect of the eyeball and orbit (and can be seen on the left side of the image). However, the muscle indicated by the blue arrow is the superior oblique muscle, which lies medial to the superior rectus muscle and the levator palpebrae superioris muscle (which can be seen lateral to the one indicated). The function of the superior oblique muscle, which is innervated by the trochlear nerve (CN IV), is to internally rotate the eyeball.
name: Abduction of the eyeball
label: b
answer: no

Correct answer: a