Vitreous-choroid-retina

What wavelength of visible light is associated with the development of macular dengeration?

• Blue-violet light between 415 nm and 455 nm

  • Death of RPE cells

• Blue-turquoise (465 to 495) doesn’t affect ocular health and is actually important for the pupillary reflex and wake/sleep cycle

  • Fluorescent lamps, LED lights, and sunlight

Blood vessels and their resistance and blood flow rate

• Retinal blood vessels:

  • small

  • high resistance

  • low flow rate (due to small lumen)

• Choroidal vessels:

  • larger

  • lower resistance

  • higher flow rate

• Ophthalmic/carotid arteries:

  • Larger than retinal and choroidal vessels

  • Even higher flow rates

How do these conditions present on FA?

• Pigment epithelial detachment

• Central serous retinopathy

• Cystoid macular edema

• Choroidal neovascular membrane

• Pigment epithelial detachment:

  • well defined pooling of dye underneath the RPE that doesn’t expand in size overtime but gets brighter instead

• Central serous retinopathy:

  • “smoke-stack” presentation due to leakage of fluorescein dye through the retinal pigment epithelium

  • Causes a hyperfluorescent spot in the early stages

  • During the later venous stage, dye will continue to pass into the subretinal space and ascend vertically to the upper limit of the detachment and then extending laterally

• Cystoid macular edema:

  • “Flower petal” pattern of hyperfluorescence

  • Accumulation of fluorescein dye inside the microcystic spaces that developed within the retina

• Classic Choroidal neovascular membrane:

  • Well defined membrane that fills with fluorescein in the early phase

  • Dye eventually leaks after 1-2 minutes in the sub retinal space surrounding the neovacular membrane

Rank how the posterior hyaloid face of the vitreous attaches to the following from strongest to weakest:

A. Retinal Blood Vessels

B. Macula

C. Optic Nerve Head

D. Vitreous Base

E. ILM

1. Vitreous base

2. Optic Nerve head

3. Macula (fairly weak attachment)

4. Retinal Vasculature (weaker)

5. ILM (weakest)

(VOM-RI)

Which vitamin when taken in excess amounts can interfere with the uptake of Vitamin A?

• Vitamin A is used to manage retinitis pigmentosa

• Vitamin E

Drusen typically deposits between which layers of the retina?

• RPE and Bruch’s Membrane

  • The RPE has an important role in phagocytosis of shed outer segments of the photoreceptors

  • If it fails to rid the debris, it will accumulate and show up as drusen → impacts vision and leads to macular degeneration

The rhodopsin molecule is found at what location in a rod photoreceptor?

• The membrane of the otuer segment

  • Rhodopsin is embedded in the discs of the outer segment of the rod photoreceptor and absorbs a photon of light, causing and electrical change in the membrane of. therod

  • Need several rods to summate in order to signal the presence of a stimulus

  • Rods then release glutamate post-synaptically to bipolar and horizontal cells

What is the Area of Martegiani

• Signifies the funnel-shaped dilation surrounding the optic disc

• Represents the posterior termination of Cloquet’s Canal (aka hyaloid canal)

List the layers of the retina starting from the retinal pigment epithelium

• Plexiforms layers are closer to the vitreous