What is the trochlear nucleus?
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What is the trochlear nucleus?
The trochlear nucleus is a small, ovoid group of neurons nestled in the medial longitudinal fasciculus of the caudal midbrain (Fig. 28.8; see p. 420). These motor neurons supply the contralateral superior oblique muscle.
Where are trochlear nucleus located?
caudal midbrain
The trochlear nucleus is located in the caudal midbrain; the functional component of these cells is general somatic efferent. After exiting at the dorsal side of the midbrain, the trochlear nerve loops around the midbrain, pierces the dura mater, and passes through the lateral wall of…
What is the function of trochlear?
The trochlear nerve is one of 12 sets of cranial nerves. It enables movement in the eye’s superior oblique muscle. This makes it possible to look down. The nerve also enables you to move your eyes toward your nose or away from it.
How many Trochlear nucleus are there?
two
The nucleus of the trochlear nerve is located in the lower midbrain, at the level of the inferior colliculus. It is a motor nucleus, so is located near the midline. The oculomotor nerve and trochlear nerve are the only two cranial nerves with nucleus in the midbrain.
What is the trochlea of the eye?
Description. The trochlea of superior oblique is a pulley structure in the eye. The tendon of the superior oblique muscle passes through it. Situated on the superior nasal aspect of the frontal bone, it is the only cartilage found in the normal orbit.
Where is the trochlear?
The trochlear nerve emerges from the back (dorsal) brainstem, just below the inferior colliculus. It circles from behind around the brainstem and runs forward toward the eye in the subarachnoid space.
What is the trochlea in anatomy?
Medical Definition of trochlea : an anatomical structure resembling a pulley: as. a : the articular surface on the medial condyle of the humerus that articulates with the ulna. b : the fibrous ring in the inner upper part of the orbit through which the tendon of the superior oblique muscle of the eye passes.
What is trochlea in anatomy?
What is the difference between oculomotor and trochlear?
While the oculomotor nerve supplies most of the extraocular muscles, the trochlear and abducens nerves each supply their own muscle.
What is the trochlea made of?
In the ocular orbit, trochlea is a fibrous cartilaginous pully like structure on the nasal aspect of the frontal bone through which superior oblique muscle passes.
What nerve in the brain controls eye movement?
The oculomotor nerve
The oculomotor nerve is the third cranial nerve (CN III). It enables eye movements, such as focusing on an object that’s in motion.
What bone is the trochlear notch on?
function and location. …large C-shaped notch—the semilunar, or trochlear, notch—which articulates with the trochlea of the humerus (upper arm bone) to form the elbow joint.
What is the common purpose of the oculomotor trochlear and abducens cranial nerves?
These three CNs are best tested together because they are all involved in ocular motility. The oculomotor nerve (III) provides innervation to all the extraocular muscles except the superior oblique and lateral rectus, which are innervated by the trochlear (IV) and abducens nerves (VI), respectively.
Which bone contains the trochlea?
In the human arm, the humeral trochlea is the medial portion of the articular surface of the elbow joint which articulates with the trochlear notch on the ulna in the forearm….
Trochlea of humerus | |
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FMA | 23370 |
Anatomical terms of bone |
What happens when the trochlear nerve is damaged?
Patients with trochlear nerve palsy complain of double vision vertically (vertical diplopia) or the images being tilted or rotated (torsional diplopia). The diplopia is binocular and may worsen or improve in different gazes.