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Contact Lens & Anterior Eye 32 (2009) 187–189
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Contact Lens & Anterior Eye
journal homepage: www.elsevier.com/locate/clae
Short Communication
The use of fluorescein in contact lens aftercare
Ian P. Davies, Jane Veys *
THE VISION CARE INSTITUTETM Johnson & Johnson Medical Ltd., Pinewood Campus, Nine Mile Ride, Wokingham RG40 3EW, UK
A R T I C L E I N F O
A B S T R A C T
Keywords:
Contact Lens
Fluorescein
Aftercare
Survey
This short communication reports on the responses of a cohort of more than 2000 contact lens
practitioners across five European countries, who were surveyed on the routine use of flourescein in soft
contact lens aftercare. Although corneal staining has received extensive interest amongst the academic
community, most practitioners do not routinely use fluorescein at aftercare visits. The arguments for not
using the agent seem to be somewhat flawed in modern contact lens practice and it is hoped by
education and wider communications of the value of staining that more practitioners use it more often.
ß 2009 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
1. Introduction
Sodium fluorescein has been used in the assessment of corneal
lesions since the 1880s and over the past hundred years it has been
used in almost all spheres of contact lens practice [1]. In contact
lens aftercare, its primary use is to examine the integrity of the
corneal and conjunctival surface, and there is no doubt that it is an
essential diagnostic tool in the identification and differential
diagnosis of many corneal lesions, and in highlighting conjunctival
changes such as Contact Lens Papillary Conjunctivitis (CLPC). The
use of fluorescein is considered by many to be an essential step in
contact lens aftercare. In the United Kingdom, The College of
Optometrists code of ethics and guidelines to the optometric
profession on the care of and refitting contact lens wearers advises
the use of ‘‘appropriate topical drugs and diagnostic agents’’ [2].
Since the 1990s there has been a large increase in the number of
peer-reviewed publications related to corneal staining and
significant interest in the contact lens community on its relevance
[3]. Much of the debate has been driven by the observations of
punctate staining associated with different combinations of
silicone hydrogel lenses and care products with resulting claim
and counterclaim of the significance of the findings. Factors such as
the period of time that staining is assessed after lens wear and the
use or otherwise of Wratten #12 filters are also contributory
factors in the levels of staining seen [4–7].
While much has been published on the incidence and potential
consequences of staining, little or no data can be found on the
extent to which practitioners routinely use fluorescein during soft
* Corresponding author. Tel.: +44 1344 864335.
E-mail address: [email protected] (J. Veys).
contact lens aftercare. This short communication will report on the
results of surveys carried out amongst contact lens fitting eye care
practitioners on their habits when prescribing, fitting and
monitoring soft contact lens wearers.
2. Methods
Between July 2006 and March 2008 2116 contact lens fitting
eye care practitioners from 5 countries/regions of Europe (Table 1),
attending courses at THE VISION CARE INSTITUTETM of Johnson &
Johnson sro in Prague and Johnson and Johnson Medical Holdings
spa in Milan, were surveyed on a number of aspects of contact lens
practice. The sample was made up of practitioners representing the
professions that carry out the majority of contact lens fitting in
each market. At the start of a presentation on the use of the slit
lamp delegates were asked: ‘‘How often do you stain a soft contact
lens wearer with fluorescein?’’ Each practitioner was presented
with 4 choices: (1) Always, (2) Most of the time, (3) Only if I think
that there is a problem, and (4) Never. The participants used a
Bosch interactive voting unit to register their responses, which
were then displayed to the whole group when everybody had
voted. The results were down loaded onto a Microsoft Excel1
spreadsheet (Microsoft Corp., USA) and the data mined using basic
table functions within the software. Linear regression analysis was
carried out on the responses of each country over time to ascertain
if this varied over the time scale of the survey. At a later stage in the
same course, practitioners were asked to estimate the amount of
corneal staining that they see in soft daily wear contact lens
wearers. They were presented with 4 options: less than 10%, 10–
19%, 20–30% and greater than 30%. Once again the information was
collected using the Bosch interactive voting unit and not presented
to the class until all had voted.
1367-0484/$ – see front matter ß 2009 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.
doi:10.1016/j.clae.2009.05.004
I.P. Davies, J. Veys / Contact Lens & Anterior Eye 32 (2009) 187–189
188
Table 1
Eye care practitioner sample.
Country/region
Germany
Italy
Poland
Scandinavia
United Kingdom
4. Discussion
Number of
practitioners
Profession
Ophthalmologist
Optometrist/
Optician
440
433
397
306
540
1%
5%
82%
3%
3%
99%
95%
18%
97%
97%
3. Results
Significant differences were found in the responses of practitioners from different countries (Fig. 1), with the UK being the only
group in which over 50% of respondents claimed to use fluorescein
at each appointment. Combining the top two box responses of
‘‘Always’’ and ‘‘Most of the time’’ showed 3 distinct clusters. The UK
group had the highest number of respondents with 75% in this
category, Poland and Italy were next with 45% then the 3rd cluster
were Germany and the Scandinavian countries with around a
quarter of practitioners. The German practitioners were the group
in which most claimed never to use fluorescein with 28% falling
into this category.
We investigated the extent to which, if any, the number of
practitioners who claimed to use fluorescein on a regular basis
changed over time. For all countries there was no evidence of any
change in the response rates over the study period with correlation
coefficients being 0.2 or less in all cases.
In general, practitioners from the countries that reported using
fluorescein the most, also reported seeing the highest incidence of
corneal staining (Fig. 2). Similarly the practitioners who stained the
least, trended towards reporting seeing the lowest incidence of
staining.
Fig. 1. Frequency of use of corneal staining with soft contact lens wearers.
Fig. 2. The reported incidence of corneal staining as a function of the frequency with
which fluorescein is used.
The results of this study suggest that although the topic of
corneal staining may be growing in interest amongst the academic
community, most practitioners (with the exception of UK sample)
do not routinely use fluorescein at soft lens aftercare visits. In
addition there is some evidence, albeit on a relatively small base
that the increased interest in the subject has not significantly
changed usage patterns over the study period. A potential
limitation to this data is the extent to which the samples used
reflect the contact lens fitting population at large. The practitioners
attending the classes at THE VISION CARE INSTITUTETM had
applied and were invited without any level of pre-selection. It is a
reasonable assumption that the groups had a higher interest in
contact lens practice than an unselected random group of
practitioners. Additional work would be interesting to see if the
use of fluorescein was related in any way to the level of experience
of the practitioner, which was not captured in this sample.
Notwithstanding these challenges, the question remains why is
it that between 25% and 75% of practitioner only use fluorescein
when they think there is a problem, or not at all. In some countries
within Europe, fluorescein is either not readily available or there
are legislative limitations on its use by non-ophthalmologists
which we have see significantly lowers the frequency of its use [8].
In all of the countries sampled in this report there are no such
reasons why fluorescein may not be used by contact lens
practitioners. During the classes discussions occurred with the
participants on the reasons for their responses, and follow up
discussions with the trainers and the authors broke the reasons for
not using fluorescein down into 2 main categories:
1. Concerns about discolouration of the lens following fluorescein
installation.
2. Concerns about the risk of Pseudomonas aeruginosa infection
from fluorescein left in the eye following the installation.
It is interesting to question these ‘‘excuses’’ in the context of
contact lens practice in the 21st century. Certainly in the days of
expensive conventional lenses that were expected to last for 2–3
years the fear of anything that might detract from the lens
condition was a real one. Fluorescein is a water-soluble dye that is
absorbed into a hydrogel lens as a function of the amount in the
tear film. While high molecular weight fluorescein is often cited as
a means of reducing this absorption its primary use is to examine
the fit of a soft lens and its reduced fluorescence vs. regular sodium
fluorescein reduces its effectiveness in looking at corneal staining.
The biggest factor in reducing the possibility of discolouration is
the volume of solution applied to the eye. The use of lower
concentrations of fluorescein either with a moistened fluoret or 1%
minim was shown to be the most effective clinically [9]. In all cases
the goal should be to reduce the volume of fluorescein delivered to
the eye, which can be achieved by reducing the surface area of the
fluorescent strip that is wetted [10]. The use of a minimally wetted
fluorescein impregnated strip will reduce the volume of solution
available to discolour the lens as well as improve its diagnostic
value. The increased use of disposable lenses further invalidates
fears about discolouration given the ability to affordably change
the lens if it becomes discoloured. A single drop of saline in the eye
in which a minimum amount of fluorescein has been placed is
usually sufficient to remove any excess—in practice a ‘wash out’ is
rarely required, a short time delay before lens insertion sufficing.
The concerns about Pseudomonas aeruginosa infection are
interesting to explore, it is a Gram-negative, aerobic rod belonging
to the bacterial family Pseudomonadaceae. It is also one of the
most common pathogens associated with microbial keratitis, and
as such a concern to all contact lens practitioners [11]. The
I.P. Davies, J. Veys / Contact Lens & Anterior Eye 32 (2009) 187–189
association with fluorescein seems to stem from a case report
published in 1955 in which a number of cases of pseudomonas
infection were attributed to colonisation of un-preserved fluorescein sodium solutions in a hospital eye clinic [12]. A subsequent
study failed to colonise sterile strips of fluorescein that were
inoculated with the bacteria [13]. It would seem therefore that the
introduction of fluorescein from sterile strips wetted with a sterile
saline solution would seen to be unlikely to exacerbate any
infection.
So should we encourage contact lens practitioners to use
fluorescein more often? While the debate continues about the
significance of superficial punctate staining of the corneal and its
relevance there is no doubt that fluorescein staining indicates an
insult to corneal integrity whether it be in the contact lens wearer
or non wearer, in which staining is also frequently found [3]. The
peer-reviewed standard for good clinical practice in the UK,
The College of Optometrist’s guidelines are clear on the need for
the use of ‘‘diagnostic agents’’ although they fall short of
specifying which are to be used. Personal correspondence with
eye care practitioners from around the rest of Europe indicates
that such guidelines do not always exist to define the scope of
good clinical practice.
Practitioners who report using fluorescein the least are also
those that report seeing the lowest incidence of corneal staining.
While it could be argued that their belief that corneal staining is a
rare event drives their behaviour in not using the agent more,
discussions with those practitioners tends not to support this
contention. The practitioners who use fluorescein, see staining
incidences that are more in line with the literature. While not all
corneal staining is clinically significant or requires intervention, if
the practitioner knows that it is there then an informed clinical
judgement can be made.
The arguments for not using the agent seem to be somewhat
flawed in modern contact lens practice and it is hoped by education
189
and wider communications of the value of staining that more
practitioners use it more often.
Acknowledgments
The authors would like to thank all the faculty members of THE
VISION CARE INSTITUTETM who participated in the collection of
this data and inputted into the discussion. Thanks also to Ivanna
Bartakova, Kamila Rychecka, Daniela Mitri and Angela Quitadamo
for their help in collating the information.
References
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Guidelines_home/.
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