Unlike
correcting contact lenses worn to improve
vision, non correcting coloured contact
lenses are not presently classified as
medical devices. As a result they are not
subject to the usual controls rightly imposed
on corrective contact lenses by the Directive
93/42/CEE.
The
ophthalmic section of the UEMS, which
represents some 40,000 ophthalmologists
across the EU, wishes to emphasize that
whether worn for recreational or esthetic
reasons, non corrective coloured contact
lenses should still fall within the definition
of a medical device. They are often used
in clinical practice as a medical prosthesis
to camouflage a damaged cornea, or therapeutically
to block light so as to alleviate photophobia
as seen in albinism, some congenital
anomalies or trauma to the iris (1).
They modify the anatomy of the anterior
surface of the eye.
All
contact lenses applied to the front of
the eye alter the oxygenation and thereby
the metabolism of the cornea. Whatever
they are made of must allow adequate
oxygen transfer (2). The pigments used
for colouring a lens must be non toxic
to the ocular surface. The lenses must
be stored in sterile packaging to avoid
contamination and germ transmission.
Their manufacture must answer to all
the strict quality and tracking norms
so as to be able to guarantee them by
the CE mark of products in class IIa.
Contact
lenses are the most common cause of corneal
infections in developed countries (3).
The cases published in the scientific
literature in the last few years (4,5,6,7,8,9,10)
witnesses the importance of the risk
of severe corneal infection (infectious
keratitis) associated with non corrective
coloured contact lenses. This may result
in serious damage to the vision, in some
cases requiring a corneal graft. In many
cases, it is the total lack of information
and counseling on the rules of hygiene
and maintenance of contact lenses which
is at the root of infection. In fact,
the unregulated sale of these products
in supermarkets and on the internet deprives
the customer, often an adolescent, from
benefiting from recommendations on hygiene
and maintenance usually given by a professional.
A recent study has shown that the purchase
of contact lenses over the internet is
a factor in the risk of complications
(11).
The
Unites States and Japanese governments
are aware of these problems and have
favourably responded to pressure from
professional organisations to class non
corrective coloured contact lenses as
medical devices and tighten the control
of their distribution. As official representative
of the ophthalmologists of the European
Union, the Section of Ophthalmology of
the UEMS demands, in the interest of
public health, that the European Commission
and the Parliament adopt similar measures
for Europe.
References
(1)
Cole CJ, Vogt U., Medical uses of cosmetic
colored contact lenses. Eye Contact
Lens. 2006 Jul;32(4):203-6.
(2)
Holden B., Merz G., Critical oxygen levels
to avoid corneal oedema for daily and
extended wear contact lenses. Invest. Ophthalmol.
1984, 25: 1161-1167
(3)
Bourcier T, Thomas F, Borderie V, Chaumeil
C, Laroche L. Bacterial keratitis: predisposing
factors, clinical and microbiological
review of 300 cases. Br J Ophthalmol.
2003 Jul;87(7):834-8.
(4)
Johns KJ, O’Day DM. Pseudomonas
corneal ulcer associated with colored
cosmetic contact lenses in an emmetropic
individual. Am J Ophthalmol 1988 Feb
15;105(2):210
(5)
Connell BJ, A Tullo, P B Morgan, and
M Armstrong. Pseudomonas aeruginosa microbial
keratitis secondary to cosmetic coloured
contact lens wear. Br J Ophthalmol. 2004
December; 88(12): 1603–1604
(6)
Steinemann TL, Fletcher M, Bonny AE,
Harvey RA, Hamlin D, Zloty P, Besson
M,
Walter
K, Gagnon M. Over-the-counter decorative
contact lenses: Cosmetic or Medical Devices?
A Case Series. Eye Contact Lens. 2005
Sep;31 (5):194-200
(7)
Colin J, Aitali F, Malet F, Touboul D,
Feki J. Bilateral infectious keratitis
in a patient wearing cosmetic soft contact
lenses. J Fr Ophtalmol. 2006 Jun;29(6):665-7
(8)
Gagnon MR, Walter KA. A case of acanthamoeba
keratitis as a result of a cosmetic contact
lens. Eye Contact Lens, 2006 Jan;32(1):37-8
(9)
Lee JS, Hahn TW, Choi SH, Yu HS, Lee
JE Acanthamoeba keratitis related to
cosmetic contact lenses. Clin Experiment
Ophthalmol 2007 Nov;35(8):775-7
(10)
Kerr NM, Ormonde S. Acanthamoeba keratitis
associated with cosmetic contact lens
wear. N Z Med J. 2008 Nov 28;121(1286):116-9.
(11)
Stapleton F, Keay L, Edwards K, Naduvilath
T, Dart JK, Brian G, Holden BA. The incidence
of contact lens-related microbial keratitis
in Australia. Ophthalmology. 2008 Oct;115(10):1655-62. |