CXL-365 vario
corneal cross-linking
1025_IFU_507536 CXL-365 vario_EN_Rev 09
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1
Introduction
1.1
Intended use and indication
The product is a portable medical device to emit UV light of wavelength 365 nm using a light emitting
diode (LED). The device is used for the treatment of keratoconus (cone-shaped cornea). The
irradiation of the cornea with the UV light in combination with a photo sensitizer (riboflavin solution -
mix ratio: 0.1% riboflavin (vitamin B2), 20% dextran T500 in isotonic NaCl solution (pH 7.0)) leads to a
corneal cross-linking and thus to a stabilization of corneal shape.
The drug vitamin B2 (riboflavin photo sensitizer lotion) is not part of the product. The
drug vitamin B2 is excluded from the declaration of conformity to this device.
1.2
Contraindication
The UV radiation may cause a cell damage of the eye. 95% of UV radiation is absorbed in conjunction
with the photo sensitizer (riboflavin solution) in the cornea. Corneal endothelial cells, located on the
back of cornea, have a damage threshold of 0.36 mW / cm². This value is not reached during the
irradiation with riboflavin at a depth of the cornea of more than 300 microns. Minimum thickness of
the cornea is specified as a criterion for the feasibility of treatment with UV irrad Riboflavin
lotion. The thickness has to be at least 400 µm or more [1]. In corneal thickness of less than 400
microns no treatment may be carried out.
[1]
Eberhard Spörl, Christine Wittig; Universitäts-Augenklinik Dresden; CLL Kongress 2005
Furthermore patients with the following characteristics must not be treated:
•
Patients with active medical implants
•
Patients with aphake- / pseudoaphake eyes
•
Patients with prior herpectic infection (It may result in viral reactivation)
•
Patients with concurrent infection
•
Patients with severe corneal scarring or opacification
•
Patients with history of poor epithelial wound healing
•
Patients with severe ocular surface disease (ex. Dry eye)
•
Patients with autoimmune disorders
1.3
Known side effects
Based on current information no side effects are known to crosslinking with described UV light
sources.
Nevertheless there are side effects like inflammation related to the surgical procedure.
