Which eye muscle passes through the trochlea and turns the eye inferiorly and laterally?

a. Lateral rectus muscle

b. Inferior rectus muscle

c. Inferior oblique muscle

d. Superior oblique muscle

Video transcript

Hi, everyone. Let's take a look at this practice problem together when the left eye is looking at an object on the floor and it rolls to the left, determine which muscle moves the left eye to track it. The answer options are a superior oblique, B, inferior oblique, C, lateral rectus and D medial Rectus. For this question, let's go ahead and review the action of each of these muscles. So option A recall that the superior oblique depresses the eye and turns it laterally. The inferior oblique elevates the eye and turns it laterally. The lateral rectus makes the eye move to the lateral side and the medial rectus moves the eye immediately. The question asks, what muscle controls the movement of the eye as it looks down into the left side of the body. So what muscle makes the eye look down and laterally? Well, option D the medial rectus, we can eliminate this right away because this is a muscle that produces medial movement, not lateral. We can also eliminate option B, the inferior oblique, this muscle elevates the eye or makes the eye look upwards. And that is why option B is incorrect. Now, the lateral rectus. Option C only moves the eye in one direction to the lateral side. It does not make the eye move downward toward the floor. So we can also eliminate option C. So the correct answer is option. A, the superior oblique muscle loops through what's called the trachea. And this is a pully like structure. So using this pulley like structure, the contraction of the muscle causes the eye to look down and laterally to the left side. So the correct answer is option, a superior oblique. All right, everyone. I hope you found this helpful and I'll see you soon for the next practice problem.