Term
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Definition
| The time that a current 2x threshold intensity must flow in order to elicit muscle excitability |
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Term
| What is the ratio of the chronaxie of the palpebral orbicularis oculi compared to the orbital orbicularis oculi and what is the significance? |
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Definition
| The palpebral orbicularis oculi's chronaxie is 1/2 the orbital orbicularis oculi. A smaller chronaxie means more rapid movement. The palpebral o.o. is for rapid involuntary eye movement. The orbital o.o. is for slower voluntary eye movement. |
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Term
| What is Sherrington's law of reciprocal innervation and give an example in the eyelid. |
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Definition
When one muscle contracts, its opposite muscle relaxes. bicep/tricep
When the LPS contracts, the OO relaxes. |
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Term
| The fact that your righ and left LPS and o.o. contract together is an example of what law of innervation? |
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Definition
| Hering's law of equal innervation |
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Term
| Which muscle controls tonic eyelid position in states of arousal in which serum levels of catecholamines are higher through alpha 2 receptors? |
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Definition
Muellers muscle
Beta 2 receptors is the le"b"ator muscle. |
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Term
| Which muscle lies beneath the levator, 15 mm from the upper tarsal border and inserting on the superior tarsal border? |
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Definition
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Term
| What division of the nervous system innervates Muellers muscle? |
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Definition
| sympathetic nervous system |
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Term
| What is the only muscle responsible for lower lid depression? |
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Definition
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Term
| What is Bell's phenomenon? |
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Definition
| An upward and outward rotation of the globe with forced closure. |
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Term
| What glands secrete the outer lipid layer? |
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Definition
| Meibomian glands, Zeiss, Mol |
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Term
| What glands secrete the outer lipid layer? |
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Definition
| Meibomian glands, Zeiss, Moll, corneal and conjunctival epithelium |
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Term
| What glands secrete the middle aqueous layer? |
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Definition
| Main lacrimal gland, and the accessory glands of |
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Term
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Definition
| The deep portion of the orbicularis muscle that inserts onto the posterior lacrimal crest (located medially) and though to be important in lacrimal outflow |
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Term
| What is senile entropion and which eyelid does it effect most? |
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Definition
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Term
| What is cicatricial entropion and what does it effect? |
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Definition
| usually upper eyelid, due to |
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Term
| What is spastic entropion? |
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Definition
| overactive septal portion of orbicularis causes override of tarsal portion, same as flaccid ectropion or paralytic ectropion |
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Term
| What is atonic ectropion? |
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Definition
| outward turning of lower eyelid frollowing paralysis of orbicularis oculi muscle |
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Term
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Definition
| adhesions of upper and lower lid |
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Term
| What do you call inverted epicanthal folds? |
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Definition
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Term
| What do you call ankyloblepharon totale? |
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Definition
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Term
| What do you call a failed closure of the fetal fissure? |
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Definition
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Term
| What do you call the loss of eyelid tissue by atrophy? The fold of the tissue hangs over the eyelid. It comes with age or youth following chronic edema. The tonus of the levator is normal. The tissue is what is stretched. |
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Definition
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Term
| What do you call it when the brow sags? It's a pseudoptosis because the tissue is drooping not the lid. |
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Definition
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Term
| What is the inability to close the eyelids? |
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Definition
|
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Term
| What is an uncontrolled twitching of the eyelid? |
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Definition
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Term
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Definition
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Term
| Does Bell's Palsy effect voluntary or involuntary movements more? |
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Definition
| Involuntary movements are usually not effected. It effects CNVII |
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Term
| What are two symptoms of Bell's Palsy? |
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Definition
1) widened palpebral fissure
2) Lagopthalmos |
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Term
| On what two muscles does the resting lid position depend? |
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Definition
1) Levator superioris\
2) Mueller's muscle |
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Term
| How much does the lower lid move from the up to the down gaze? |
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Definition
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Term
| How many mm of opening in the palpebral fissure is due to the LPS? |
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Definition
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Term
| How many mm of opening of the palpebral fissure is due to the frontalis muscle? |
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Definition
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Term
| What is the biggest clue to pathology of the distance of opening in the palpebral fissure? |
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Definition
| asymetry between right and left eye |
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Term
| In which type of ptosis does the normal lid move lower upon downgaze? |
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Definition
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Term
| What type of ptosis is associated with leavtor dehiscience, but the levator function is still preserved? |
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Definition
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Term
| Myasthenia gravis (autoimmune), Horner's (sympatheitic) and CN III dysfunction are associated with what type of acquired ptosis? |
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Definition
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Term
| Blepharochalasis, Enopthalmos (microopthalmia, phthsis), protective , and retraction of the fellow eye are all examples of what type of ptosis? |
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Definition
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Term
| What is the 2nd most common cause of lid retraction. It's a pretectal/dorsal midbrain lesion-posterior commissure disease. Pateints exhibt a characteristic stare. Patient commonnly has an upgaze paresis. |
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Definition
| Collier's sign (symmetric UL retraction) |
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Term
| What is responsible for 90% of eyelid retraction clinically? |
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Definition
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Term
| What is a widening of the palpebral fissure due to excessive tonus of Muller muscle or excessive tonus of the levator palpebrae? |
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Definition
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Term
| Do patients with a goiter have a wider or smaller palpebral fissure? |
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Definition
| wider, 32% bigger than 19 mm as opposed to only 5% normal people bigger than 19mm |
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Term
| Wat is the inability of the upper lid to follow the movments of the globe in "downgaze". It is often referred to as lid lag. It maybe also due to retraction of the upper eyelid. |
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Definition
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Term
| What two structures control lid apposition to the globe? |
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Definition
1. Tarsal plate and the palpebral ligaments
2. Muscle of Riolan |
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Term
| What is a droopin gof the upper eyelid due to paralysis of the oculomotor nerve (N III) or sympathetic nerve or by excessive weight of the upper eyelids |
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Definition
|
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Term
| What is an exaggerated reflex blinking? |
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Definition
|
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Term
| What is the decreased size of the palpebral fissure, often due to increased distance between the inner canthui (telecanthus, and drooping upper eyelid (blepharoptosis) |
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Definition
|
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Term
| Which way does the UL move when the eye closes? |
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Definition
|
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Term
| When way does the lower lid move when it closes? |
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Definition
| mostly nasal, depresses momentarily when contacted by the upper lid |
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Term
| Which way does the medial canthus move when the lid closes? |
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Definition
| It stays stationary for the most part. |
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Term
| What are three types of blinking? |
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Definition
1. spontaneous
2. reflex
3. voluntary |
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Term
| How fast can you close an eye? |
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Definition
| twice as fast as you open it |
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Term
| What type of blinking reflex is lost in contact lens wear? |
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Definition
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Term
| Which muscle of the iris is at the pupillary margin? |
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Definition
| Sphincter, dilator is radial and consists of short fibers bound by connective tissue |
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Term
| Which muscle is innervated from the E-W nucleus-Ciliary ganglion synapse? |
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Definition
Sphincter muscle,
Dilator is Superior cervical ganglion-sympathetic plexus at carotid-sympathtic root pass through the ciliary glaglion-SPCN |
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