SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
molecule at physiological pH and is easily soluble in water. Ultrasound and the use
of nano-emulsion systems can also aid permeation.
Post radiation treatment consists of topical Tobramycin or other good quality
antibiotics such as Vigamox for 7 days and Atropine drops for 3 days. Oral Flunixin
[Finadyne] can be used for 7-10 days. Post operative check up examinations are
recommended: 1 day, 3 days, 1 week, 1 month and 3 months. The median time
range for healing appears to be 4–26 days after CXL. Some eyes may show
improved clinical signs from 3 days. This can be in the form of reduction of
inflammatory signs, including reduced signs of ocular pain, decrease in corneal
oedema and ciliary injection and less aqueous flare and inflammatory cells in the
anterior chamber. The stromal melting can also be stopped when re-examined the
day after treatment. In 2–4 days, a granular appearance of the denuded stromal
tissue has been noted and in some cases a rejection of necrotic mucoid tissues
follows. Ingrowth of blood vessels to the ulcerated area and regeneration of the
corneal stroma and re-epithelialisation could be observed.
It has been shown that one can perform a small window of epithelium debriding
whereby riboflavin can penetrate into the stroma. This may be an advantage in
cases of infectious ulcerative keratitis
Bullous keratopathy:
A variety of problems in the eye can result in endothelial cell damage and
subsequent corneal oedema and distension. These include endothelial dystrophy
[band keratopathy], iris-to cornea persistent pupilliary membranes, trauma [surgical
and non-surgical], anterior uveitis, glaucoma, and melting keratitis. As a result of the
endothelial cell damage, fluid moves into the stroma, causing corneal oedema;
keratoconus and bullae formation can occur. Historically 5% NaCl hypertonic eye
drops have been used to attempt to dehydrate the cornea by hydroscopic action.
Their effect is extremely variable.
CXL with riboflavin decreases corneal oedema and increases visual acuity in human
patients with bullous keratopathy. The presumed mechanism is the increase in
collagen packing density and a reduction in swelling tendency of the
glycosaminoglycan-rich hydrophilic ground substance of the cornea.
Melting corneal ulcers [keratomalacia]
In the article by Famose [2015] he describes the use of CXL to treat melting corneal
ulcers in cats. One of the observations was the improvement in pain levels in all
affected cats after the CXL and that re-epithelisation was noted in 90% of cats within
8 days. He also noted reduced corneal vascularization and all eyes had visual
function. Melting resolved in 7 days with all cases and can be attributed to the direct
effects of CXL. It appears the CXL may have three specific effects on the cornea; a
bactericidal effect, increase in corneal resistance to mechanical forces and
enzymatic digestion and the reduction in corneal inflammation. The bactericidal
effect has been attributed to bacterial DNA and membrane alterations and the
liberation of free radicals by photo-activation of riboflavin. The increased corneal
mechanical strength is related to the increase intralamellar covalent binds whilst the
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