What is the H test for eyes?

What is the H test for eyes?

The test itself is simple. Your eye healthcare provider or technician will ask you to sit up straight while you stare at an object in front of you, which is usually a pen, fixation light, or small picture held 12 and 16 inches away. They will move the object up and down and side to side in an H-shaped pattern.

What are the 7 extraocular muscles?

Extraocular muscles

• Superior rectus.
• Inferior rectus.
• Lateral rectus.
• Medial rectus.
• Superior oblique.
• Inferior oblique.
• Levator palpebrae superioris.

How many extraocular muscles are in the eye?

The contributions of the six extraocular muscles to vertical and horizontal eye movements. Horizontal movements are mediated by the medial and lateral rectus muscles, while vertical movements are mediated by the superior and inferior rectus and the superior (more…)

What are extraocular movements?

The extraocular muscles execute eye movements and are innervated by three cranial nerves. Contraction of the medial rectus pulls the eye towards the nose (adduction or medial movement). Contraction of the lateral rectus pulls the eye away from the nose (abduction or lateral movement).

What test assesses extraocular muscles?

The extraocular muscle function test is performed to evaluate any weakness, or other defect in the extraocular muscles which results in uncontrolled eye movements. The test involves moving the eyes in eight different directions in space to evaluate the proper functioning of the extraocular muscles of the eyes.

What is the purpose of the extraocular muscles?

The extraocular muscles, are the seven extrinsic muscles of the human eye. Six of the extraocular muscles control movement of the eye and the other muscle, the levator palpebrae, controls eyelid elevation.

What are the 6 ocular movements?

You are now familiar with the 6 cardinal directions of gaze (right/up; right; right/down; left/up; left; left/down), as well as the remainder of the yoked eye movements (straight up; straight down; convergence).

What is the extraocular muscle function test?

The extraocular muscle function test is performed to evaluate any weakness, or other defect in the extraocular muscles which results in uncontrolled eye movements. The test involves moving the eyes in six different directions in space to evaluate the proper functioning of the extraocular muscles of the eyes.

What are the four extraocular muscles and their functions?

The 4 extraocular muscles that control eye movement in the cardinal directions (along with their functions) are the superior rectus, inferior rectus, lateral rectus and medial rectus muscles. In the neutral position, this muscle is responsible for elevation, incyclotorsion and adduction (inward, rotational movement).

What determines the direction of movement of the extraocular muscles?

The position of the eye at the time of muscle contraction is what determines how the 6 muscles of the orbit are engaged. Four of the 6 extraocular muscles controls movement in the cardinal directions: north, east, south, west (or up, right, down, left).

Which extraocular muscle has the longest tendon in the eye?

Resection of the inferior rectus muscle results in lower lid narrowing (eyelid moves up). The superior oblique muscle has the longest tendon of all the extraocular muscles (26 mm).