11.3 Age-related Muscular Degeneration

Question 1

Macula
REP

Answer 1

Small spot at center back of retina
High density of photoreceptor

Retinal pigment epithelium:
Metabolic support for photoreceptors

Question 2

AMD

Answer 2

Age-related macular degeneration:
RPE around Macular degenerate as age increase, photoreceptor in macular die
Irreversible central visual loss

Question 3

Risk factors of Age-related macular degeneration

Answer 3

• Increasing age
• Genetic
• Unhealthy diet (high sat fats, sugar, low antioxidants)
• Smoking
• Blue wavelength

Question 4

AMD type

Answer 4

Dry AMD
Late-stage dry AMD
Wet AMD

Question 5

Dry AMD

Answer 5

1. Drusen (yellow-pigment, debris of dead RPE) deposit and accumulate under RPE
2. RPE atrophy
3. breakdown photoreceptor in macular
4. Increase no., enlarge, calcify of spots
   Central vision decrease

Question 6

Late-stage dry AMD

Answer 6

More widespread loss of RPE (atrophy)
More photoreceptor die
Central irreversible vision loss

Question 7

Wet AMD

Answer 7

1. New abnormal blood vessel growth under RPE
2. Choridal neovascularization = Blood vessels leak, bleed, form scar
3. Macula bulge, Detachment of central fovea
4. Profound and rapid vision loss

Question 8

Clinical manifestations of AMD

Answer 8

Painless
Distortion & blurring of central vision

Blindless
Object show difference color, size, shape in each eye
One eye first then another

Question 9

Investigation of AMD

Answer 9

VA Visual acuity
Retinal examination

1. Amsler grid
2. Fluorescein angiography (FA)
3. Optical coherence tomography

Question 10

Amsler grid

Answer 10

With reading glasses, Bottom portion of bifocals, 14inches, fix gaze on center black dot

Normal: lines straight, unbroken, no missing areas
Abnormal: lines distorted or broken,
Mark the defect and consult

Question 11

FA

Answer 11

Fluorescein angiography:
Study retina and choroidal circulation
-Dye intravenously (7s reach retina)
-Shone blue light into, emit green light in blood vessels

Question 12

OCT

Answer 12

Optical coherence tomography:
cross-section picture of retina
Using light waves
If thinning/ thickening/ swelling

Question 13

Prevention for AMD

Answer 13

• Intake antioxidant-rich food
  Antioxidant: Vitamin C, E, carotenoids and zinc
  antioxidant-rich food: dark green leafy, fruit
  (Limit effect of free radicals produced in process of light absorption)
  (Protect macula from sun damage)
• caritenoids
• Uv protection for eyes
• avoid smok

Question 14

Management for wet AMD

Answer 14

• Anti-VEGF agents (-zumab)
  Slow formation of abnormal blood vessels
  (VEGF induce angiogenesis and increase inflammation and vascular permeability in retina)
• laser photocoagulation on source of leakage
  But recurrence and damage nearby tissue
• photodynamic therapy (photosensitivity drugs +infrared light)
  Seal off vessel when drug activity by light