12 - Fundoscopy/Vitreous

Question 1

Hruby lens

• indications
• interpretation

Answer 1

NON-CONTACT exam of optic disc, macula, post pole, central vitreous

Stereoscopic, erect, magnified

Question 2

3-mirror lens

• indications
• interpretation
• angles/views

Answer 2

Exam of retina from optic disc -> ora

Stereoscopic, reversed (ant-post direction), magnified, 180 deg away

Trapezoid: 73 deg, equator
Square: 67 deg, peripheral (b/w ant equator + ora)
Bullet: 59 deg, apical (AC angle, ora)

Question 3

78/90D lens

• indications
• interpretation

Answer 3

Easier than Hruby/3-mirror
Magnification/FOV directly proportional to lens power

REAL, INVERTED, REVERSED, magnified image

Question 4

BIO

• indications
• interpretation

Answer 4

Routine comprehensive exam

REAL, INVERTED, REVERSED, magnified image

Question 5

Scleral depression

-indications

Answer 5

Similar to 3-mirror
Allows OBLIQUE VIEWING OF RETINA -> incr contrast, easier identification of abnormalities

Do NOT perform on recent sx/trauma, hyphema, ruptured globe

Question 6

Green/red-free filter

Answer 6

Differentiation of NFL, choroidal lesions, retinal vasculature

Question 7

Asteroid hyalosis

• who
• signs/symp

Answer 7

Aging, 0.5% population over 60

Signs: numerous small, yellow-white, refractile particles of CALCIUM-PHOSPHATE SOAPS attached to collagen fibrils
-75% unilateral

Symp: asymptomatic

Question 8

Synchysis scintillans

• pathophys
• signs

Answer 8

Rare, occurs AFTER chronic uveitis, vit hem, trauma

Unilateral, golden-brown, refractile CHOLESTEROL CRYSTALS that are freely mobile (often settle inferiorly)q

Question 9

Posterior vitreous detachment

-epidemiology/hx

Answer 9

Females
Approx age after 50
Myopes: occurs avg 20yrs earlier than emmetropes
Other risk factors: DM, intraocular sx/inflammation, vit hemorrhage, trauma

Question 10

Posterior vitreous detachment

-pathophys

Answer 10

HA-collagen* complex is disrupted with age -> collagen clumps up
*T2 collagen

Liberated collagen can contract within complex -> posterior hyaloid detaches from retina

Pockets of liquefaction (syneresis) can travel thru the hole in pos hyaloid + cause separation b/w vitreous and retina

Posterior = post hyaloid pulls away from retina
Anterior = ant hyaloid pulls away from lens

Question 11

Posterior vitreous detachment

• # 1 spot for tear following
• at ONH
• at macula
• PVD = #1 cause for (3)

Answer 11

Ora/vitreous base

Weiss ring

Macular hole

Mac hole, ERM, VMT

Question 12

Posterior vitreous detachment

-signs/symp

Answer 12

Signs: weiss ring, ant displacement of post hyaloid, vitreous pigment cells* (“tobacco dust”/ Shafer’s sign), vit hemorrhage
*is RPE released into vitreous, look for retinal tear

Symp: acute onset floaters, flashes of light*, decr vision
*photopsia due to traction

Question 13

Vitreous traction

-can result in (5)

Answer 13

ERM
Macular hole
Vitremacular traction
Vitreous/retinal hemorrhage
Retinal breaks

Question 14

ERM

Answer 14

Glial tissue from back of vitreous or intraretina (thru pore -> ILM) left after PVD

Question 15

Preretinal/Vitreous hemorrhage

-epidemiology/pathophys

Answer 15

DRVOS condns + trauma

Preretinal (in vitreous) neovascularization: lacks endothelial TJs
Vitreous traction -> shearing of BVs

Because vitreous is weakly attached to BVs in NFL/INL (weakest vitreous attachment), can have bleeding/hemorrhage without a tear in vitreous = preretinal

Question 16

Preretinal/Vitreous hemorrhage

-signs/symp

Answer 16

Preretinal: intact posterior hyaloid (b/w ILM + post hyaloid)

• no symptoms unless macula-involving
• very RED, keel-shape (BOAT-SHAPED)

Vitreous: broken posterior hyaloid

• sudden, painless vision loss and/or black spots with corresponding flashing lights
• mild = only obscures part of the fundus
• severe = whole fundus
• CHRONIC = YELLOW

Question 17

3 concerns that DRVOS condns can lead to

Answer 17

Pre-retinal/vitreous heme (BVs break)

Tractional RD (vit PULLS ON BVs, which DON’T break -> whole retina forward)

VEGF -> NVG (esp with CRVO)