Eagleview Eye Clinic

Archives April 2026

ICG ANGIOGRAPHY

ICG angiography = Indocyanine Green Angiography. It’s an imaging test that maps blood flow in the choroid, the blood-vessel layer under your retina.

What it is

  • Dye test: A green dye called indocyanine green is injected into your arm vein
  • Infrared camera: Special camera uses near-infrared light at 790-805 nm to see the dye through the retinal pigment
  • Shows choroid: Unlike fluorescein angiography which shows retinal vessels, ICG goes deeper and highlights choroidal circulation

Why doctors order it

  • See through blood/pigment: ICG light penetrates melanin, fluid, and thin blood. Useful when fluorescein images are blocked
  • Diagnose specific conditions:
    • Choroidal neovascularization (CNV): Especially “occult” CNV hidden under the retina in AMD
    • Polypoidal choroidal vasculopathy (PCV): Branching vessels with polyp-like aneurysms, common in African/Asian patients
    • Central serous chorioretinopathy (CSCR): Shows choroidal hyperpermeability areas
    • Lacquer cracks: Checks if CNV is growing through the cracks
    • Inflammatory diseases: Vogt-Koyanagi-Harada, choroiditis, to see active lesions
    • Tumors: Choroidal melanoma vs nevus

How the test works

  • Prep: Pupils dilated. You’ll sign consent and get an IV line
  • Injection: 25 mg ICG dye injected into arm. It binds to plasma proteins and stays inside blood vessels
  • Imaging phases:
    • Early 0-1 min: Choroidal arteries and choriocapillaris fill
    • Mid 5-15 min: Venous phase and leakage patterns show
    • Late 20-30 min: Staining or “washout” patterns. Polyps stay bright late
  • Time: Takes 20-30 minutes total

ICG vs Fluorescein angiography
Feature ICG Fluorescein
Light used Near-infrared 790-805 nm Blue light 490 nm
What it shows Choroidal vessels Retinal vessels
Dye leakage Minimal. Stays in vessels Leaks easily from damaged vessels
See through blood Yes No
Best for PCV, CSCR, occult CNV, choroidal tumors Diabetic retinopathy, vein occlusion, macular edema
Safety & side effects

  • Very safe: Severe reaction rate is about 0.05%, much lower than fluorescein
  • Common effects: Temporary green discoloration of skin, green urine for 1 day
  • Mild reactions: Nausea in 1-2%, sneezing, itching
  • Contraindications: Iodine allergy because ICG contains iodine. Also avoid in liver disease and pregnancy unless essential
  • No kidney issues: Unlike CT contrast, ICG isn’t nephrotoxic

What to expect after

  • Vision: Not blurred by the dye itself, but dilation makes you light sensitive for 4-6 hours
  • Drive: Bring someone. You can’t drive until dilation wears off
  • Results: Retina specialist reads images same day and decides on treatment like anti-VEGF or photodynamic therapy

Bottom line: If fluorescein angiography shows the retinal circulation, ICG shows the “basement” blood supply under it. It’s the go-to test when doctors suspect PCV, CSCR, or hidden CNV, especially in highly pigmented eyes.

LACQUER CRACKS

Lacquer cracks are breaks in Bruch’s membrane, a thin layer in the back of your eye. They’re mostly linked to high myopia but can show up in other conditions too.

What exactly breaks?

  • Location: Bruch’s membrane sits between the retinal pigment epithelium (RPE) and the choroid. It’s like the “basement membrane” for the retina
  • The crack: Think of paint on a wall. If the wall stretches too much, the paint develops hairline cracks. Same idea when the eyeball elongates in high myopia
  • Appearance: On eye exams, they look like yellowish, irregular lines in the back of the eye, often near the macula

Main causes

  • Pathologic myopia: Biggest cause. Eyes longer than 26.5 mm or stronger than -6.00D stretch Bruch’s membrane until it tears
  • Trauma: Blunt injury to the eye can cause acute cracks
  • Angioid streaks: Associated with systemic diseases like pseudoxanthoma elasticum, Ehlers-Danlos, Paget’s disease. Angioid streaks can develop lacquer cracks
  • Choroidal neovascularization: Sometimes new blood vessels form around the cracks

Symptoms

  • Often none early: Many people have lacquer cracks with no vision change
  • If macula involved: Blurred vision, distorted vision where straight lines look wavy, or a blind spot
  • Sudden vision drop: Usually means a complication like bleeding or CNV has started

Complications to watch for

  • Choroidal neovascularization (CNV): New, leaky blood vessels grow through the crack. This is the main threat to vision and can cause bleeding/scarring
  • Subretinal hemorrhage: Blood under the retina from CNV, causes sudden central vision loss
  • Fuchs’ spot: Pigmented scar that forms after a bleed heals. Leaves permanent central scotoma

How doctors diagnose

  • Dilated fundus exam: Doctor sees yellow lines
  • OCT scan: Shows the break in Bruch’s membrane and any fluid/blood
  • Fluorescein angiography: Dye test to check for CNV leaking through the crack
  • ICG angiography: Better for seeing deeper choroidal vessels

Treatment

  • No fix for the crack itself: Bruch’s membrane can’t be stitched back. Goal is to manage complications
  • If CNV develops: Anti-VEGF injections like Avastin, Lucentis, or Eylea into the eye to stop new vessels
  • Monitor: Regular OCT scans if you have lacquer cracks, especially with high myopia
  • Lifestyle: No proven way to prevent them, but controlling myopia progression in kids may help reduce future risk

Who’s at risk

  • High myopes: -6.00D or worse, or axial length >26.5 mm
  • Age: Usually appears in 20s-40s in myopic patients
  • Family history: Pathologic myopia runs in families

Bottom line: Lacquer cracks themselves don’t always hurt vision. The danger is when new blood vessels grow through them. If you have high myopia, get yearly dilated eye exams so any CNV gets caught early.

DIETARY REQUIREMENTS FOR THE EYES

Dietary requirements for the eyes — what you eat directly affects your retina, lens, tear film, and optic nerve. Here’s the breakdown:

1. Omega-3 fatty acids: DHA & EPA

  • Why: DHA makes up 50-60% of fatty acids in your retina. Keeps photoreceptor cells flexible. EPA reduces eye surface inflammation
  • Sources: Salmon, mackerel, sardines, anchovies, fish oil supplements
  • Target: 2-3 servings fatty fish per week or 1000-2000 mg combined EPA+DHA daily
  • Benefits: Helps dry eye, meibomian gland function, may lower AMD risk

2. Lutein & Zeaxanthin

  • Why: These carotenoids form the macular pigment. Acts like “internal sunglasses” that filter harmful blue light
  • Sources: Kale, spinach, collard greens, egg yolks, corn, orange bell peppers
  • Target: 6-10 mg lutein + 2 mg zeaxanthin daily. AREDS2 used 10 mg + 2 mg
  • Benefits: Reduces risk of macular degeneration and cataracts

3. Vitamin A + Beta-carotene

  • Why: Vitamin A makes rhodopsin, the pigment your rods need for night vision. Deficiency = night blindness
  • Sources: Liver, dairy, eggs for preformed A. Carrots, sweet potatoes, pumpkin for beta-carotene
  • Target: 700-900 mcg RAE daily. Don’t overdo supplements because high dose vitamin A can be toxic
  • Benefits: Cornea health, night vision, prevents xerophthalmia

4. Vitamin C

  • Why: Antioxidant in the aqueous humor of your eye. Helps regenerate vitamin E and supports blood vessels
  • Sources: Oranges, guava, bell peppers, strawberries, broccoli
  • Target: 75-90 mg daily. AREDS used 500 mg for AMD patients
  • Benefits: Slows cataract progression, supports collagen in cornea/sclera

5. Vitamin E

  • Why: Protects eye cell membranes from oxidative damage
  • Sources: Almonds, sunflower seeds, avocado, wheat germ oil
  • Target: 15 mg daily. AREDS used 400 IU
  • Benefits: Works with vitamin C and zinc to slow AMD

6. Zinc

  • Why: Concentrated in retina and choroid. Helps vitamin A move from liver to retina to make melanin, a protective pigment
  • Sources: Oysters, beef, pumpkin seeds, cashews, beans
  • Target: 8-11 mg daily. AREDS2 used 80 mg zinc oxide, but high doses need copper added
  • Benefits: Critical for night vision and AMD risk reduction

7. Water & general hydration

  • Why: Your tear film is 98% water. Dehydration = worse dry eye
  • Target: About 2-3 L fluid daily depending on climate and activity
  • Benefits: Better tear volume, less gritty eyes

8. Other helpful nutrients

  • Vitamin D: May reduce inflammation in dry eye and AMD. Source: Sun, fatty fish, fortified milk
  • B vitamins: B2, B6, B12, folate help lower homocysteine, linked to retinal vein issues
  • Selenium & Copper: Cofactors for antioxidant enzymes in the eye

Sample eye-friendly day

  • Breakfast: Eggs with spinach + orange
  • Lunch: Grilled sardines, kale salad, almonds
  • Snack: Carrot sticks + guava
  • Dinner: Sweet potato, baked salmon, broccoli

Key rule: Eat colorful. Dark green, orange, yellow, and red foods usually pack the carotenoids your eyes need.