Trans 011 Disturbance In Vision : Posterior Segment

Question 1

clear,

avascular, gelatinous body that comprises two-thirds of the volume and weight of
the eye.

Answer 1

Vitreous

Question 2

thin, semitransparent, multilayered sheet of neural
tissue that lines the inner aspect of the posterior two-
thirds of the wall of the globe.

Answer 2

Retina

Question 3

posterior segment of the uveal tract, between the retina and the sclera.

Answer 3

Choroid

Question 4

The tube running to the connecting lens to the optic nerve/disc, where the vessels of the retina developing.

Answer 4

Cloquet’S canal

Question 5

also known as the hyaloid
canal or Stilling’s canal, is a transparent canal that runs
from the
optic nerve
disc to the lens traversing the vitreous
body. It serves as a perivascular sheath surrounding the
hyaloid artery in the embryonic eye.

Answer 5

Cloquet’S canal

Question 6

prevents most of the misfocused rays from entering the eye. Only a few centrally aligned focused rays will reach the retina, resulting in a sharper image.

Answer 6

Pinhole vision

Question 7

What are included in the anterior segment

Answer 7

o Statusofcornea
o Anterior chamber (Ac) 
o Iris
o Lens
o Anterior vitreous
o Pupillary reactions

Question 8

Normal and typical optic disk diameter

Answer 8

1.5-2mm

Question 9

doctor uses this microscope to shine a beam of light
shaped like a small slit on your eye. They may also dilate your pupils during the test. It can help diagnose cataracts, glaucoma, detached retina, macular degeneration, cornea injuries, and dry eye disease.

Answer 9

Slit lamp biomicroscopy

Question 10

is a technique for examining the circulation of the retina and choroid (parts of the fundus) using
a fluorescent dye and a specialized camera.

Answer 10

2. FUNDUS FLUORESCEIN ANGIOGRAPHY (FA OR FFA)

Question 11

is superior for imaging the choroidal circulation, particularly when there is surrounding or overlying blood, exudate, or serous fluid.
 Uses indocyanine green (ICG)  More on the choroid

Answer 11

ICG ANGIOGRAPHY (ICGA)

Question 12

is a computerized, cross-sectional tomographic imaging modality used to examine and measure intraocular structures in three dimensions.

Answer 12

OPTICAL COHERENCE TOMOGRAPHY

Question 13

OPTICAL COHERENCE TOMOGRAPHY

Answer 13

OCT ANGIOGRAPHY (OCTA)

Question 14

What are we using for color vision testing

Answer 14

Farnsworth and Ishihara test

Question 15

metamorphopsia versus micropsia

Answer 15

Metamorphopsia-Alterations in shape or may distorsion

 Micropsia- mas lumiit

Question 16

Scotoma

Answer 16

Blind spot

Question 17

Liquefaction of gel with age / symptoms: floaters and flashes o Liquefactionaccompaniedbydetachmentoftheposterior
hyaloid or cortex (PVD)
o At age 50 years, around 30% have vitreous liquefaction
and hyaloid detachment / 60% at 70 yrs.
o Pathologic if there are retinal tears and vitreous
hemorrhage
 Remember that vitreous syneresis is a normal
physiologic part of aging process. But it can
become pathologic.
o Liquefaction can happen in trauma, vitreous hemorrhage,
intraocular inflammation, surgery

Answer 17

Vitreous SYNERESIS

Question 18

Symptoms:
o floatersandflashes
o sudden significant loss of vision
 pwede naman hindi complete loss, depende sa thickness of hemorrhage
• Possible causes:
o Vitreous detachment with avulsion of retinal vessels and
retina
o bleeding from proliferative diabetic retinopathy
o bleedingfromneovascularelementsfromvaso-occlusive
disease o trauma
o Valsalva retinopathy
 When you lift something heavy (e.g
weightlifters) or in bungee jumping when you hold your breath and may pressure sa jugular vein → puputok retinal vessels
o breakthrough bleeding from choroidal neovascular membranes
o choroidal tumors/ others

Answer 18

VITREOUS HEMORRHAGE

Question 19

Treatment of VITREOUS HEMORRHAGE

Answer 19

Treatment:
o High Back Rest
 First thing to do. Head up, 45 degrees inclined.
o restrict activities
o addressspecificetiology

Question 20

Reason for a flat top in pre retinal (subhyaloid) hemorrhage

Answer 20

Yung vitreous cortex natin nakasandal sya sa retina diba I
told you? Pero that attachment ay walang real attachment walang cementing substance don eh, parang static adhesion lang sya. Pag nag bleed yung isang blood vessel dun sa retina, pede syang maipon in that space between the retina and the posterior hyaloid
→ that is why you have a flat top (yellow broken line)

Question 21

2 types of maculopathies

Answer 21

Central Serous Chorioretinopathy (CSR)
o AgeRelatedMacularDegeneration(ARMD)

Question 22

Pathophysiology:
o fluid accumulation in the subretinal space (between rods
and cones & retinal pigment epithelium) due to defect in RPE. What disease

Answer 22

CENTRAL SEROUS CHORIORETINOPATHY

In CSR, something is wrong in the pigment epithelium ( 3 red lines). Pigment epithelial cells are incompetent so nakakalagpas ang fluid from the choroid paakyat under the retina (pink arrow).

Question 23

Symptoms
o blurry central vision
o metamorphopsia
o micropsia
o change in color perception at central visual field (color
change)
• Usually in young males
• Usually Type A personality
• Highly related to stress
• Cause unknown
• No known treatment
• Laser may sometimes be indicated

Answer 23

CENTRAL SEROUS CHORIORETINOPATHY

Question 24

Difference of neovascular versus non-neovascular age related macular degeneration

Answer 24

Neovascular -sudden onset of blurry central vision, sudden onset of scotoma at or close to the center of vision, metamorphopsia

non neovascular- gradual progressive loss of central vision

Question 25

Females > Males by about 50% 6-10% in ages between 65 and 74 20-30% at 75 yrs and above number 1 cause of severe visual loss in the western world in those over 50 yrs. > 200,000 new cases reported yearly in USA AGE is the single most important and consistent variable Hereditary factors o 10-20%havefamilyHxoflossofcentralvision Smoking o smokershave3Xtheriskofnon-smokers Lack of antioxidants Overexposure to UV light / blue light damage What discourse?

Answer 25

AGE RELATED MACULAR DEGENERATION

Question 26

Treatment for age related macular degeneration

Answer 26

``` Treatments: central vision ✓ Sudden onset of a of central vision ✓ scotoma at or close to the center of vision Metamorphopsia o o o o o o Pharmacologictherapy ▪ anti VEGF (ranibizumab, bevacizumab, aflibercept), intraocular steroids ( Ozurdex implant) Photodynamic therapy (verteporfin) Photocoagulation: ▪ directed to the neovascular membrane / applicable for extrafoveal CNVMs  you can only do laser if wala sa gitna, extrafoveal Choroidal Neovascular Membranes Submacular surgery Macular translocation Gene Therapy  Injection in the eye is the most common, but expensive. ```