Boards Prep: Ocular Anatomy Video

Question 1

1. Does the Superior Oblique Attach Anterior/Posterior to the Equator?
2. From there, where does it attach (what area of the eye)?
3. What does this tell us about the Action of the SO?
4. How many degrees out isolate the Recti?
5. How many degrees out isolate the Obliques?

Answer 1

1. Posterior to the Equator
2. Attaches to the Back LATERAL SIDE of the Eye.
3. Primary action is to cause INTORSION.
4. 23 degrees
5. 51-55 degrees

Question 2

1. What makes up the Lateral Wall of the orbit?
2. What makes up the Superior wall?
3. Medial Wall: (ELMS)
4. Where do all of the Recti muscles originate from?
5. What sits in front of the Superior Orbital Fissure?

Answer 2

1. Greater wing of the sphenoid bone and the Zygomatic Bone
2. Frontal bone and Lesser wing of the Sphenoid Bone
3. Ethmoid, Lacrimal, Maxilla, and Sphenoid bones
4. The Annulus of Zinn
5. The Common Tendinous Ring

Question 3

1. A Pt has a lesion within the Common Tendinous Ring. What would you expect? (NOAh)

Answer 3

1. Nasociliary Nerve (Corneal Innervation), Oculomotor Nerve (CN 3: Accommodation, Miosis, Levator, 4/6 EOMs), and Abducens Nerve

Question 4

1. What makes up the inferior Orbit? (My Pal gets his Z’s on the floor)

Answer 4

1. Maxillary, Palantine, Zygomatic

Question 5

What are the 3 Branches of V1 (NFL)

2. What are the 2 Branches of the Frontal Nerve?

Answer 5

Nasociliary Nerve (Cornea)

Frontal Nerve (Center of Forehead)

Lacrimal Nerve

2. Supratrochlear (More medial) and Supraorbital (right above the orbit) Nerves

Question 6

What does V3 do?

**CN V: Sensory Sensory Sensory w/a little bit of Motor

2. What Reflex does CN 5 do?

Answer 6

1. Sensory for Mandible as well as innervation to the Muscles of Mastication (esp…the Masseter Muscle)
2. Reflex BLINKING (Sensory portion)…Afferent

Question 7

CN 7: Motor Motor Motor, with a little bit of Sensory

1. What are the Motor Functions?
2. What’s the Sensory function?

Answer 7

1. Facial Expression, Closing the Eye (Orbicularis Oculi)

2. Lacrimation (REFLEX TEARING!!!)

Question 8

1. What Reflex Blinking can CN 2 do?
2. What Reflex Blinking does CN V do?
3. What Reflex Blinking does CN 8 do?

Answer 8

1. DAZZLE (Bright light) or Denace the Menace (someone coming to punch you in the face)
2. Something touching your cornea/eye (ie, Cotton Swab Test)
3. LOUD NOISES can cause u to blink.

Question 9

What does the SPCAs do?

Answer 9

1. Circle of Zinn

Question 10

CN 12 Lesion on right side, what will happen to the tongue?

Answer 10

1. The tongue will deviate towards the right.

Question 11

CN 10: Vagus: Lesion: What will u see occur with the uvula if the lesion is on the right?

Answer 11

The uvula will deviate to the left.

Question 12

Which CNs have Parasympathetic function?

(Lacrimation…reflex tearing)

(Accommodation and Miosis)

Answer 12

CN 7 (Pterygopalantine or Sphenopalantine Ganglion)

CN 3 (3—> Ciliary Ganglion)

Question 13

Which CNs have Sympathetic Function to the eye?

(Meuller’s Muscle)

(Dilator Muscle)

Answer 13

3 to Meullers, 5 to Dilator (Nasociliary Division of V1 and it’s the Long Ciliary portion)

*SNS: Big Mooch

Question 14

1. Where are the Glands of Wolfring Located?

2. Where are the Glands of Krausse located?

Answer 14

1. TARSAL CONJ

2. In the Creases (the Fornices)

Question 15

1. What’s the most common Epithelial Dystrophy?

2. Whats the most common Stromal Dystrophy?

Answer 15

1. EBMD (classic finding: NEGATIVE STAINING: Due to AD dystrophy that results in EXCESSIVE BM Production…pushing epithelium out in that area)
2. Granular

Question 16

What are the strongest attachments (Strongest to weakest) of the Vitreous?

Answer 16

1. Ora Serrata –> Posterior Lens –> ONH –> Macula —> Retinal Vessels

Question 17

1. What are the major constituents of the Vitreous?

2. What do they form?

Answer 17

1. Hyaluronic Acid and Collagen (Type 2 i think…)

2. Form a network w/in the vitreous (80%)

Question 18

What border is marked by the Y sutures (ie, what’s the nucleus called that’s b/w them)?

2. Why does the RI go from bigger to smaller as you go from central to periphery in the Lens?
3. Why is the center of the lens have the HIGHEST RI?
4. What happens with age to the crystalline proteins w/in the lens? (increase or decrease)

Answer 18

The FETAL NUCLEUS

• Embryonic Nucleus (1.50) sits in the very center
  2. To reduce CA and Spherical aberrations.
  3. Because that’s where the lens has the highest concentration of crystalline proteins.
  4. They DECREASE

Question 19

1. What happens in the OPL? (Synapse)
2. What about IPL?
3. What 2 dzs happen in the OPL?
4. When you’re seeing BVs in the retina, what 2 layers are they from?
5. In Retinoschisis (Splitting) what layer splits?

Answer 19

1. Synapses b/w the Bipolar the photoreceptor and Horizontal cell
2. Bipolar, Ganglion, and Amacrine
3. Retinoschisis, Hard Exudates
4. NFL (Drance Hemes, Spot Hemes, CWS), and the INL (Dot Blot Hemes…bigger hemes)
5. OPL

Question 20

Why do ERMs occur?

2. Where do Glial Cells come from?

Answer 20

1. Due to Vitreotraction, but it’s due to Glial Cell Proliferation.
2. From the Vitreous (pulls on the ILM…some thinking they are on the back of the Vitreous to start with, and they pull, leaving some glial cells behind), or from w/in the retina to start with, the vitreous pulls on it, creating a space, and glial cells perculate thru the ILM and build up on the ILM.

Question 21

1. Fovea: What are the retinal layers in the fovea?

Answer 21

1. Photoreceptor layer…axon extends into what is now called Henle’s Fiber Layer (and not the OPL..axons of photoreceptors)

**No bipolar and Ganglion cells…(cells were pushed aside to the PARAFOVEA….Thickest are of the Retina as well as highest concentration of those cells as well)

*RPE, Photoreceptor, ELM, ONL, Henle’s Fiber Layer…ILM

Question 22

1. What provides the majority of blood supply to the Macula (or occipital lobe i guess…)
2. What’s the #1 reason for a Macular Sparing effect?
3. What’s the #1 reason for having a macular involving vision loss?

Answer 22

1. Posterior Cerebral Artery
2. Stroke
3. Both Posterior and Middle Cerebral Arteries were affected (Tumor most likely) (out field answer: 2 strokes, each knocking each artery out)