Term
| Which muscles are responsible for opening the eyelid? |
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Definition
1. levator palpebrae superioris
2. the retractors of the lower lids
3. Smooth Muscle of Mueller |
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Term
| Which muscle is responsible for eyelid closure? |
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Definition
| The orbicularis muscle that encompasses the palpebral fissure. |
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Term
| What happens when the levator muscle disinserts from the tarsal portion of ht eyelid? |
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Definition
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Term
| Why does the eyelid crease appear higher in cases of ptosis? |
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Definition
| The lid is still in tact. |
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Term
| What is the most common type of ptosis? |
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Definition
| aponeurogenic-this is where the aponeurosis disinserts |
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Term
| What type of ptosis results from Horner's syndrome or CNIII dysfunction? |
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Definition
Neurogenic ptosis
With Horner's syndrome it is congenital but with Myasthenia Gravis it is acquired |
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Term
| What type of ptosis would be associated witha tumor, hemiangioma, neurofibroma, or cicatrization secondary to inflammation |
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Definition
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Term
| What are the four most common etiologies of ptosis? |
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Definition
1. Dermatochalasis
2. Intraocular surgery
3. Trauma
4. Congenital |
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Term
| What are six less common etiologies of ptosis? |
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Definition
1. Myasthenia gravis
2. Horner's syndrome
3. Third nerve palsy
4. Topical steroids
5. Botulinim toxin
6. Corneal and external diseases |
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Term
| What are 8 causes of pseudoptosis? |
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Definition
1. Dermatochalasis
2. Brow ptosis
3. Enopthalmos from trauma-e.g. blow out fracture
4. Phthisis bulbi
5. Microphtalmia (smal eye)
6. Chalzaion or other eyelid tumors
7. Eyelid edema
8. Hypotropia (e.g. double elevator palsy)
9. Retraction of the contralateral eyelid |
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Term
| What is the main type of receptor on the muscle of Mueller and what does it do? |
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Definition
| The muscle of Mueller is a minor retractor. The main receptor type is alpha 2 |
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Term
| What is the main receptor of the levator? |
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Definition
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Term
| Which muscle of retraction plays the greatest role when you are excited? |
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Definition
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Term
| What Cranial nerve innervates the orbicularis oculi, the main muscle used to close the eyelid? |
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Definition
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Term
| What parts of the orbicularis muscle are responsible for the blink reflex or unforced eyelid closure? |
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Definition
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