Table Of ContentELSEVIER
BUTIERWORTH
HEINEMANN
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Foreword
Eye Essentials isa series of books intended to cover the core
skillsrequired bythe eye care practitioner ingeneral and/or
specialized practice.Itconsists of books covering awide range of
topics rangingfrom: routine eye examination to assessment and
management of low vision;assessmentand investigative
techniques to digitalimaging;case reports and lawto contact
lenses.
Authors known for their interest and expertise intheir
particular subject havecontributed books to this series.The
reader willknow manyof them,as they havepublished widely
within their respective fields.Eachauthor hasaddressed key
topics intheir subject ina practical rather than theoretical
approach,hence each book hasa particular relevance to everyday
practice.
Eachbook inthe series follows a similarformat and has been
designed to allowthe reader to ascertain information easilyand
quickly. Eachchapter has been produced ina user-friendlyformat,
thus providingthe reader with a rapid-reference book that iseasy
to use inthe consulting room or inthe practitioner's free time.
Optometry and dispensing optics are continually developing
professions,with the emphasis ineach being redefined as we
learn more from research and as technology stamps its mark.
The Eye Essentials series isparticularly relevant to the
practitioner's requirements and as such willappeal to students,
graduates sitting professional examinations and qualified
Foreword
practitioners alike.We hope you enjoy reading these books as
viii much aswe haveenjoyed producing them.
Sandip Doshi
Bill Harvey
Introduction
Towards the end ofa sighttest,one ofthose utterances that the
busypractitioner maydread is'Iwas wondering whether to go
for contact lenses'. Practitioners who do not regularlyfitcontact
lenses are often convinced that it has allbecome a bittoo
complicated,and that contact lenses are best leftto the experts,
whoever they are. Patients are discouraged from too activean
interest byrather vaguelynegativeadvice.Of course,there are
practitioners who activelyencourage their patients to use
contact lenses,but inthe UKthey are a smallminority.Part of
the reason maybe that Britons are uncomfortable with the active
promotion ofanything,for fear of beingthought ofas'pushy' or
(brace yourselves) 'showing off'.However,this seems a poor
explanation for a UKcontact lens market of7%ofthe
population, compared with a USmarketof 15%.There mayalso
be a confidence factor at work here. ManyUKpractitioners have
lost touch with modern contact lens practice, or at least aspects
of it.The reasons vary.Some smallrural practices maysimplynot
generate very much contact lensworkat all,or little beyond the
odd dailydisposable.Some busy practices employ contact lens
fitters, and the optometrists rarely see the contact lens patients
exceptfor their spectacle refractions. Some optometrists have
taken a career break,to raise children or pursue a different
career path.After afew years infull-timemanagementofeither
type,the contact lensworld can appear dauntinglyunfamiliar.
When the authors beganfittinglenses,there were onlyafew
Introduction
soft lenses available,so lens material selection was easy.
x Some ofthem wetted better than others,but none of them
transmitted a decent amount of oxygen. Inthose simpler times,
aftercare was also relativelyeasy.The slit-lamps thatwe had were
notgood enough to see much (indeed, itwas not uncommon to
practise without one), and when we did see something,we either
did not know what caused it or did not havelenses that would
deal with it.Aswith certain soap operas,you could take a year
offthem and not havea lot to catch up with.These dayswe can
see more and do more,and havea huge and bewildering choice
ofoptions.What iseven worse,so do the patients. At one time,
professional knowledge could be jealously hoarded.but now
anyone with a computer and halfan hour can gainaccess to
astonishing levelsof technical and clinicalinformation.This has
spawned that most dreaded of patients - the 'Internet Bully'.
Usuallymale,and not promoted to the levelsthat his intellect
demands (at least inhisopinion). the Internet Bully surfs the web
for ammunition with which to harass hisoptometrist.(And
probably hisdoctor,dentist,and any other sort of'ist' he
consults.)
This book and its companion volume (Rigid Gas-Permeable
Lenses) are aimed at those colleagues who wish to re-enter the
contact lens mainstream,aswell as those entering itfor the first
time as students and pre-registered optometrists.Italso aims to
meet the requirements suggested inour new General Optical
Council entry levelcompetencies.to which allqualified
practitioners are meant to adhere ifthey are to maintain their
place on the General Optical Council register. It isnot intended
to be comprehensive or overly academic, but should enable the
practitionerto givesound advice to their patients,and should
provide a basison which to buildshould they wish to specialize
further. And you should be able to handle the Internet Bully too.
Dedication
Such isthe pace ofchange.most contact lens books go outof
date rapidly.So read itfast!
Acknowledgments
We are grateful to Chanel Kingand Heidi Harvey for their
assistance with photographs.
1
Initial consultation
Introduction 2
Shouldthis patient be wearing contact lenses? 2
Ocular health 3
General health 3
Visual factors 4
Psychological factors 5
Occupation and lifestyle 6
Financial considerations 6
Softor rigid? 7
Patient examination 8
General observation ofthe eyeand adnexa 8
Assessment ofthe palpebral conjunctiva 9
Assessmentofthe bulbar conjunctiva 11
The tearfilm 12
General examination ofthe cornea 15
Specific examination ofthe cornea 19
Bluelightexamination ofthe cornea 22
References 24
Initial consultation
Introduction
2
The initial consultation with a prospective contact lens wearer is
an important dialogue between the practitioner and patient that
hasa number ofgoals:
1. to establish whether the patient issuitable for anytype of
contact lens correction
2. to identifythe optimal contact lens correction for the
individual patient
3. to establish reasonable expectations for the performance of
the lenses and care system
4. to educate the patient so that their use of the lenses willbe
safeand sensible
S. to determine baseline information that can be used to monitor
change that can influencefuture management decisions.
The majority of contact lensfitting iselective
(i.e.non-therapeutic),and the patientwillexerta degree of
control over the lenses selected and their compliance with care
systems.The principle of informed choice isimportant here.
The patient must be givenenough information to make
appropriate decisions (Le.those the practitioner approves of).
The dayswhen the practitioner held a monopoly on information
havelongdeparted. Most patients who presentfor contact lens
fittingwillalso possess a computer and internet access.
Therefore.information that isincorrector out of date willbe
easilydetected,with consequent loss of credibilityfor the
practitioner.It isimportantthat practitioners keep themselves
wellinformed on current developments.
Should this patient be wearing contact
lenses?
There are fewabsolute contraindications to contact lenswear
these days,although there are manymore issues that maylimitit,
or make it more complicated for the patient or practitioner.
Should this patient be wearingcontact lenses]
Ophthalmologic consultation isessential before fitting anyeye
with active corneal pathology,and infectiveconditions should be 3
eliminated before fitting to minimizethe risk of microbial
keratitis.The patient should be aware of anyfactors that will
increase their risk,so that they can weighthis against the
benefits.
Ocular health
1.Ocular surface disorders maycause problems:
(a) Recurrent erosions maybe associated with anomalies of
the basement membrane ofthe epithelium. Insevere
cases, a bandage lens maybe indicated.
(b) Recurrent bacterial infections willincrease the riskof
microbial keratitis significantlyand ingeneral contact
lenses should be avoided insuch patients.
2. Dry eye isthe most commonly encountered complication.
The effect on contact lens wear can be predicted bythe
severity of symptoms and corneal staining encountered before
fitting.People with milder symptoms can usuallybe given
contact lenses,at least for part-time wear.
3. Meibomian gland dysfunction (MGD) can be a significant
factor incontact lens intolerance and its prevalence is
age-related. Fewer than 20%of patients under 20 years of
age presentwith it,but two-thirds of over-65s are found to
have MGD.
General health
Both systemic pathology and the medication used to treat it may
be significantfactors when considering contact lenses.
1. Allergies maybe associated with a poortear filmand a
tendency to develop inflammatory reactions to solutions or
lens deposits. Dailydisposable lenses or non-preserved
solutions maybe indicated.
2. Chronic infections such as sinusitis or catarrh maycause
excessive mucus inthe tears.The eyes mayalso be more
prone to infection.
