Opthamology Flashcards
What does Levator palpebrae superioris do?
Elevates the upper eyelid
What nerve innovates Levator Palpebrae Superioris?
the oculomotor nerve (CN III)
The superior tarsal muscle (located within the LPS) is innervated by the sympathetic nervous system.
What is Horner’s syndrome?
Triad of symptoms produced by damage to the sympathetic trunk in the neck:
Partial Ptosis, Miosis and Anhydrosis
Which muscle of eye movement is innervated by CN VI?
Lateral Rectus
Which muscle of eye movement is innervated by CN IV?
Superior oblique
Which nerve innovates the superior oblique muscle of the eye?
CN IV - Trochlear nerve
Which nerve innovates Lateral Rectus of the eye?
CN VI - Abducens nerve
Where do the Recti muscles of the eye originate?
The common tendinous ring
Where does Superior oblique attach?
Originates from the body of the sphenoid bone. Its tendon passes through a trochlear, and then attaches to the sclera of the eye, posterior to the superior rectus
What is the action of Superior Oblique?
Depresses, abducts and medially rotates the eyeball.
Which muscle depresses, abducts and medially rotates the eyeball?
Superior oblique
Where does the inferior oblique attach?
Originates from the anterior aspect of the orbital floor. Attaches to the sclera of the eye, posterior to the lateral rectus
What is the main action of Inferior oblique?
Elevates, abducts and laterally rotates the eyeball
Which muscle elevates, abducts and laterally rotates the eyeball?
Inferior oblique
Which nerve innovates the Inferior Oblique muscle?
Oculomotor nerve (CN III)
Which muscles does CN III (occulomotor) innervate?
Medial Rectus
Superior Rectus
Inferior Rectus
Inferior Oblique
What would a third nerve palsy look like?
The affected eye is displaced laterally by the lateral rectus and inferiorly by the superior oblique. The eye adopts a position known as ‘down and out’.
Which palsy produces the effect of a ‘down and out’ eye?
A third nerve palsy
Which palsy presents with the patient complaining of double vision and tilting of the head to try and rectify this?
Fourth nerve palsy - paralysis of the superior oblique muscle
How does a fourth nerve palsy present and which eye muscle(s) are affected?
A lesion of CN IV will paralyse the superior oblique muscle.
There is no obvious affect of the resting orientation of the eyeball. However, the patient will complain of diplopia (double vision), and may develop a head tilt away from the site of the lesion.
What does a sixth nerve palsy look like and which muscle is affected?
A lesion of CN VI will paralyse the lateral rectus muscle
The affected eye will adducted by the resting tone of the medial rectus.
Which nerve palsy presents with the eye being adducted medially
Sixth nerve palsy (paralysis of Lateral Rectus)
What is the muscle responsible for superior eyelid movement?
Levator palpebrae superioris.
What is Entropion?
When the eyelid (typically the lower lid) turns inward. In turned eyelashes cause irritation to the cornea