Lightmed LightLink CXL, Руководство оператора

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The primary contradiction for the corneal cross-linking procedure would be for patients
with:
- Patients with corneal thickness below 350μm (after removal of epithelium) in order
to prevent the retinal exposure to the UV light.
- Patients with severe corneal tissue scarring as uneven cornea (scarred corneal
tissue) may result in hot spots or penetration of the UV light to the retina.
- Patients with Keratometry measurement greater than 58 Diopters as the cornea
may not flatten enough to make the procedure worthwhile.
-Patients with history of severe corneal herpes simplex virus, as the exposure to the
UV-A light may reactivate the virus.
- Patients with pre-existing severe dry eye disease requires preoperative treatment,
because the condition may delay epithelial healing after corneal collagen cross
linking.
Pre Treatment Tools and Equipment:
- Cross Link System
- Pachymeter
- Surgical microscope / Slit Lamp producing blue light
- Topical anesthesia drops (e.g. novesine)
- Lid speculum
- Corneal marker 8.5 mm (large edge)
- Alcohol 20%
- Eye sponges
- 1ml or 3ml Riboflavin 1% with dextran 20%
- 1ml or 3ml Riboflavin 1% without dextran
- Eye pad
- Antibiotic eye drops
- Bandage contact lens
Treatment Steps (based on conventional protocol):
Step A: Corneal Abrasion
1. Apply a drop of topical anaesthesia.
2. Check the corneal thickness by the pachymeter at the thinnest location which is
slightly de-cantered inferiorly in keratoconus patients. Usually is greater (>)
450μm, if lower then expect a thin cornea after removing the epithelium.
3. Place the speculum onto the eye. While looking thru the microscope (optional),
place the corneal marker firmly and well cantered on the cornea and administer a
few drops of alcohol 20% for 30 second then soak the alcohol with the eye
sponge.
4. Perform epithelium abrasion (usually 8-9mm).
5. Using a new corneal sponge carefully remove the fragile epithelium (Usually the
epithelium thickness is about 50μm).