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1. Contact Lens and Anterior Eye (2001) 24, 34-40
© 2001 British Contact Lens Association
Review
www,nature.com/clae
AN OPTOMETRIST'S PERSONAL PERSPECTIVE OF ASPEC'I
OF REFRACTIVE SURGERY#
JenniferP. Craig*
(Received llth July 2000; in revisedform 2nd November2000)
Abs~act-- The latter part of the last century has seen significant evolution in the area of refractive surgery, such that is has become a
viable alternative to contact lenses, or spectacles, for an increasing number ofpatients. The developments ofthe principal techniques, in
this ever-expandingfield, are reviewed, and the increasing r61eof the optometrist in the pre-, intra- and post-operative management of
the refractive surgery patient is described, based upon the author's personal experience within a non-profit, refractive surgery setting. In
addition to highlighting pertinent features of the objective evaluation ofpatients, the importance ofsubjective assessment, pre- and post-
operatively, is discussed, in terms of maximising post-surgery patient satisfaction. The scope for future research in this dynamic area is
also considered. Contact Lens and Anterior Eye (2001) 24, 34-40.
KEY WORDS: refractive surgery, LASIK,PRK, outcome, satisfaction
History of Refractive Surgery
R efractive surgery has become a realistic alternative
to spectacle or contact lens correction for many
myopic individuals. The concept of permanent correc-
tion of ametropia is not new. As early as 1857, clear lens
extraction was proposed as a means of improving
unaided vision in the highly myopic, and incisional
keratotomy was introduced in 1894. However, to date,
no single technique has proved to be ideal? The desire
to overcome the limitations of each refractive technique
and, in particular, those related to the predictability of
the post-operative healing process, have ensured that
the art and science of refractive surgery continues to
evolve.
Over the last 30 years, a number of techniques have
risen and declined in favour. The 1970's saw the rise in
popularity of radial keratotomy following the work of
Fyodorov and Durnev in Russia. The Prospective
Evaluation of Radial Keratotomy (PERK) study investi-
gated the results of a wide range of attempted
corrections over 10 years follow-up.2 These are sum-
marised in Table 1. Overall the results showed that the
technique was relatively successful, but a significant
number of subjects did complain of vision fluctuating on
a diurnal basis, by as much as five lines of Snellen
acuity. The surgical technique has been refined in
recent years, producing better clinical results in terms
of uncorrected vision, however, problems such as
progressive hyperopia and predisposition to wound
ruptures following trauma have yet to be fully resolved.
Radial keratotomy remains most popular in the United
States, and the low equipment cost combined with the
~The Irving Fatt Lecture, 2000
*PhDMCOptom FAAO
simplicity of the technique will ensure that it retains a
r61e in the treatment of low myopia)
The intrastromal corneal ring or segments (Intacs~,
Keravision Inc., CA, USA) have been promoted on the
basis that they do not interfere with the visual axis and
that the procedure is reversible# However, their
insertion requires a technically challenging operation,
which involves the insertion of polymethylmethacrylate
(PMMA) segments at two-thirds the depth of the
stroma. The degree of myopia corrected by this method
is dictated by the thickness of the segments, and is
therefore limited to around -4.00 DS, similar to levels
treated with reasonable success by RK and photore-
ffactive keratectomy (PRK). However, it should be
noted that the surgery has the potential to cause
significant corneal opacity around the area of insertion
of the PMMA.
Intraocular techniques include clear lensectomy with
posterior chamber intra-ocular lens implant but, in
addition to being associated with the standard risks of
intra-ocular surgery, including a significantly increased
risk of retinal detachment, the loss of accommodation is
often unacceptable for younger individuals. Anterior
chamber intra-ocular lenses, placed in front of the
healthy crystalline lens have also been considered, in
particular the Worst iris claw lens and the Baikhoff
angle-supported lens, although there have been reports
of progressive endothelial cell loss and low grade
anterior chamber flare with such phakic intra-ocular
lenses. ~ More recently the pre-crystalline intra-ocular
'contact lens' has been developed, and the long term
results of prospective studies which are able to
determine both the success and complications, such
as the incidence of cataract formation and pupil block
glaucoma, are eagerly awaited.6

2. Refractive surgery from an optometric perspective
JP Craig
Table 1. Summary ofdemographicfeatures, visual outcome and significant complications ofpatients in the ProspectiveEvalutaion of
Radial Keratotomy (PERK) Study.2
35
Demographics
Visual outcome
Significant complications
Sample size
Attempted range of refractive correction
Follow-up
Post-op uncorrected vision 6/6
Post-op uncorrected vision 6/12
Loss of two or more lines of BSCVApost-op
Progressive hyperopic shift
793
-2.00 to -8.75 DS
88%at 10 years
53%
85%
3%
43%
Excimer Laser Refractive Surgery
Since the first surface-based excimer laser PRK on a
human eye in 1988, excimer laser correction of myopia
has become increasingly popular.7 Early prospective
studies showed that treatment of very high refractive
errors by PRK resulted in significant corneal haze which
reduced BSCVA in an unacceptable number of subjects
such that, by 1996, the maximum attempted correction
by PRK, in the UK, was limited to -10.00 DS or less,
with many practitioners setting an upper limit of around
- 7.00 DS. However, at lower levels of myopia, PRK has
been shown to be relatively safe and efficacious with
levels of unaided vision reported in the literature as 6/6
or greater, in between 48 and 100%of subjects, and 6/12
or greater, in between 82 and 100% of subjects, for
treatments of up to - 6.00 DS over a 6.00 mm treatment
zone. Results of a large prospective study of PRK, by
McGhee and coworkers, at Sunderland Eye Infirmary,
on 323 eyes with at least 2 years follow-up, between 1993
and 1996, concluded that PRK was very successful up to
-5.00 DS (72% at least 6/6 unaided) and moderately
successful up to -10.00 DS (89% at least 6/12
unaided). 8 Beyond this level of attempted correction,
predictability was poorer, and there was an increased
risk of severe haze and loss of best spectacle corrected
visual activity (BSCVA). Myopia was found to be
corrected more fully (actual correction up to 100% of
attempted correction) than astigmatism (around 67%
mean correction). Overall, in this prospective study,
which included attempted corrections of up to -15.00
DS, between 3 and 4%ofeyes lost two lines ofBSCVAas a
result of severe haze. The results of this study compared
well to those of similar investigations around that time.9,'°
Following the pioneering work of Barraquer in 1964
and Pureskin in 1967, the technique of excimer laser in
situ keratomileusis (LASIK) was developed and the
technique as we know it today was performed on the
first human eyes in 199071 The procedure involves
anaesthetising the eye topically. A suction ring is placed
on the eye, around the limbus, and this raises the
intraocular pressure to around 60 mmHg and immobi-
lises the eye. At this time, a microkeratome is used to
create a 160 #m flap, with a nasal or superior hinge, in
the anterior cornea. Suction is then released. Laser
ablation of the exposed stroma (of pre-programmed
depth and diameter) is performed after the flap is
reflected and whilst the patient fixates a target
coincident with the laser beam. After the ablation is
complete, the flap is returned to its original position, the
interface irrigated, and is left to settle in position without
the need for sutures. Generally, the LASIK flap adheres
securely, within 2 to 5 min, to the underlying stroma.
LASIK offers a number of advantages over PRK. It
can be used to treat higher levels of myopia (with an
upper limit of around -12.00 to -15.00 DS) without
inducing the corneal haze associated with PRK. Since
the area of epithelial disruption is minimal, there is
virtually no post-operative pain and visual rehabilitation
occurs within hours to days. However, surgically, it is a
more challenging operation and, unlike PRK, requires
sterile operating conditions due to the more surgically
invasive nature of the procedure.
Hyperopic Treatments
Treatment for hypermetropia by refractive surgery has
also become available in recent years, but results are
less well supported by long-term, longitudinal studies.
Techniques include refractive lensectomy (with intra-
ocular lens implantation) 12, PRK13, LASIK14 and more
recently, holmium laser thermal keratoplasty (LTK).15In
the latter technique, the response of the corneal tissue
to the application of the laser, at several points
concentric with the limbus, around the periphery of
the cornea, is to contract, thereby increasing central
corneal curvature, and correcting hyperopia. Overall,
hyperopic corneal refractive techniques have experi-
enced only limited success, with the best outcomes in
patients with low levels of pre-operative hyperopia
(< 4.00 DS). However, the significant risk of regression
associated with these techniques, even in small
attempted corrections, has resulted in the majority still
being considered relatively investigational. 16One of the
latest methods, with encouraging clinical results in the
treatment of hyperopia (M. McDonald, BCLA keynote
presentation, Birmingham, May 2000), is conductive or
radiofrequency keratoplasty. In this procedure, heat is
applied to the cornea with radio frequency energy,
potentially causing less damage to the surrounding
tissue than previous techniques. Results of the Phase Ill
FDA clinical trials in the US are still awaited for this new
therapy.
Prospective Study of LASIK
The author has recently been involved in a large,
prospective study of LASIK, as part of the Corneal
Diseases and Excimer Laser Research Unit at the
Contact Lens and Anterior Eye

3. Refractive surgery from an optometric perspective
JP Craig
36
University of Dundee in Scotland. 17 The LASIK
procedures were performed by a single surgeon
following a standardised protocol with the Chiron
Technolas 117 or 217 scanning spot excimer laser
and the Chiron Automated Corneal Shaper to create
the flap. All patients were prescribed topical steroids
and antibiotics for 2 weeks after surgery. The following
results pertain to the first 104 consecutive primary
LASIK treatments for high myopia.18 The group
comprised 67 females and 37 males with a mean age
of 39.4 years. The mean follow-up for the group was
10.2 months at the time of collecting the data. Sixteen
of the 104 subjects required retreatment due to myopic
regression, at a mean of 12 weeks following primary
treatment. The mean spherical equivalent (sph.eq.)
(+standard deviation (SD)) prior to surgery was
-9.82+4.59 DS with a range of -1.75 to -22.75
DS. The full correction was not attempted in the
highest myopes, limited by the thickness of the cornea,
which was determined, for each patient, by ultrasound
pachymetry. The current view, based upon the
experience of LASIK surgeons to date, is that a corneal
thickness of 250 #m must remain undisturbed beneath
the flap and ablation, to minimise the risk of sequelae
such as posterior keratectasia. For any given correc-
tion, decreasing the ablation zone size will decrease
the ablation depth, however, a significant risk of post-
operative glare is associated with small ablation zones.
The magnitude of correction is therefore often dictated
by the thickness of the patient's cornea, in order that
the safe thickness of 250 #m, can be retained following
ablation. The mean (+ SD) preoperative cylinder was
-1.46+1.37 DC. At 1 year post-LASIK, the mean
refractive error (sph.eq.) was -1.3+3.0 DS and the
mean cyclinder was -0.7+0.7 DC. This was influ-
enced largely by the extreme myopes within the group.
The group was therefore divided into three groups;
moderate myopes, high myopes and extreme myopes
(Table 2) and the mean refractive error (sph.eq.) for
each group across the 12-month follow-up period was
then assessed separately. It showed that the residual
refractive error was greatest, across all the time points,
for the extremely myopic group. This is reflected by
the tabulated results which show the percentage of
subjects within each group who achieved an unaided
vision of 6/6 or better, 6/12 or better, or < 6/12. The
apparently poorer results, in the extreme myopes, is
due largely to the limitations on attempted correction
dictated by corneal thickness, described above.
LASIK Complications
The complication rate was low in this series of patients.
Intra-operatively, there were three microkeratome-re-
lated complications: two thin flaps and one button-hole
in the flap. None of these patients experienced any
adverse outcome as a result of these imperfect flaps and
achieved good levels of unaided vision, while retaining
their pre-operative BSCVA, post-LASIK. Thin flaps or
button-hole flaps (in which the flap is doughnut-shaped
with a central portion still attached to the main body of
the cornea) can occur if suction is inadequate, and the
cornea is not located in the ideal plane before the
microkeratome is activated. The intraocular pressure is
checked by applanation tonometry prior to creating the
flap to minimise the risk of such complications, but they
can also occur in cases of sudden patient movement or
severe blepharospasm. In the event of a thin, incomplete
or button-hole flap being apparent following the excur-
sion of the microkeratome, the flap is left in place
without being lifted, and the partial corneal flap allowed
to heal in position without performing the ablation.
Following successful healing in around 3 months, the
LASIK procedure may be attempted again, with the
creation of an entirely new flap.
Post-operatively, the flap was displaced in two cases
within an hour of the operation, once, on removal of the
speculum used to hold the eyelids apart during the
operation, and once by the patient who vigorously
chewed on a toffee immediately post-operatively, dislod-
ging the flap! One further flap displacement occurred
around 12 h after surgery, when the patient instilled
their prescribed topical medication and struck the flap
with the bottle tip. In all cases, the patients were
brought back to theatre, and the flap was rehydrated
and repositioned without adverse sequelae. Overall, 97%
of the group of 104 LASIK patients maintained or gained
lines of BSCVA at final flow-up. Two patients lost one
line of BSCVA (2%) and only one subject, two lines of
BSCVA (1%). In this latter patient, the loss in vision was
in fact attributable to the onset of cataract which was
subsequently removed, resulting in a final BSCVA two
fines better than initial BSCVA.
However, although results, such as these, following
LASIK surgery are encouraging in terms of speed of
Table 2. Percentageofpatients achieving 6/6 or better,6/12 or better,orpoor than 6/12 vision, unaided,following a primary LASIK
treatment.
Percentage ofpatients achieving the given levelof vision
unaided post-primary LASIK
Refractive range, Mean refraction
Myopicgroup Sample size pre-op(Sph. eq.) (Sph.eq.) 6/6 6/12 <6/12
Moderate 32 <- 8D - 4.96 DS 74% 97% 3%
High 33 - 8 to - 12 DS - 8.80 DS 50% 78% 22%
Extreme 39 >- 12 DS - 14.76 DS 4% 30% 70%
Contact Lens and Anterior Eye

4. Refractive surgery from an optometric perspective
JP Craig
recovery and unaided vision, the technique, like any
surgical procedure is not free from serious complica-
tions (Table 3).19-24Indeed, some complications appear
unique to LASII~ One patient, who was not part of the
prospective study, experienced a severe non-infective
inflammation, known as diffuse lamellar keratitis or
'Sands of the Sahara'. The aefiology of this interesting
phenomenon is unknown, but may be related to a
reaction to debris from the surgical procedure, for
example, from the microkeratome or laser plume. The
condition presents with a sand-storm appearance of the
cornea, at the level of the flap interface.25 Vision is
reduced as a result. In the majority of patients, intensive
topical steroids, for a short period of time, reduce the
inflammation and vision is restored to its full potential.
Subjective Assessment in Refractive Surgery
Clearly, success of refractive surgery cannot be mea-
sured in objective terms, such as BSCVA and residual
refractive error, alone, but must, at least in part, be
assessed subjectively. A - 12.00 DS patient who under-
goes LASIKwith an attempted correction of - 10.00 DS
may be extremely happy with a residual refractive error
of -2.00 DS and unaided vision of less than 6/12,
allowing them to be less dependent on their spectacles
and to wear more cosmetically-appealing spectacles.
Conversely, a myopic patient who has surgery for - 2.50
DS and who emerges with a residual refractive error of
plano with a - 0.50 D cylinder and vision of 6/6 unaided,
may consider that, because they feel the need to wear a
spectacle correction for driving at night, their result is
disappointing. Patient satisfaction is therefore a vital
indicator of refractive surgery success. The fact that
refractive procedures are elective surgery on essentially
healthy eyes, albeit ametropic ones, makes subjective
success all the more important. A study was therefore
conducted at the Corneal Diseases and Excimer Laser
Research Unit at the University of Dundee, to establish
the functional and satisfaction outcomes of the patients
who underwent LASIKfor high myopia.26
An anonymous 34-question, visual analogue ques-
tionnaire, which was adapted from a questionnaire that
the authors had used previously to assess satisfaction
following PRK, was posted, simultaneously, to 48
consecutive patients who had undergone primary
LASIK surgery at the Unit. This corresponded to 76
treated eyes. The response rate from the group of 28
male and 20 female subjects, with a mean age of 40.2
years, was 100%. The mean pre-operative myopia
(sph.eq.) (±SD) was -10.7+4.4 DS. In eight eyes of
seven subjects, the intended refractive end point was
greater than - 3.00 DS or the preoperative BSCVA was
less than 6/18. Of the remaining 68 eyes, 77% achieved
6/12 or better unaided vision and 32% achieved 6/6 or
better unaided vision following a primary LASIK
treatment.
The questionnaire incorporated questions about
preoperative visual function and about postoperative
status, in terms of functionalityand satisfaction. Patients
were requested to record answers to questions on a
visual analogue scale; a horizontal line anchored at each
end by two adjectival descriptors, upon which the
subject could place a mark at the point which best
represented their opinion. For example, in asking the
patient how they rated their unaided vision pre-
operatively, the line would be anchored by a descriptor
such as 'very poor' at one end and 'very good' at the
other end. For ease of analysis, the lines were
subsequently divided into four equal categories corre-
sponding to responses of 'very positive', 'positive',
'negative' and 'very negative' for each question.
All subjects considered their preoperative unaided
vision to be poor, with 92%rating it 'very poor'. Only 34%
of subjects had rarely, or never, worn contact lenses,
and approximately equal numbers of subjects were
wearing spectacles and contact lenses prior to surgery.
Despite being a predominantly presbyopic group, the
majority of subjects reported an improvement in the
ability to undertake near tasks unaided, following
surgery. Only 4% noted a subjective deterioration in
reading in daylight, and 9% in artificial light. The
majority of subjects reported an improvement in their
ability to watch television, drive in daylight or view a
cinema screen without correction, however a number
were aware of visual difficulties when driving at night
(9%). None of the patients with difficulties had a central
ablation zone of less than 5.0 mm and, in all cases, the
centration of the zone was within 0.5 mm of the virtual
37
Table 3. Reported complications ofLASIK surgery,z9-24
Complications ofLASIK surgery
Intra-operative Post-operative
Thin/incomplete flap
Button-holeflap
Free/macerated flap
Full-thicknesscorneal cut
Minor corneal bleeding
Epithelial abrasion
Inadequate sucfion/IOP elevation
Primary over or under-correction
Decentred ablation
Subconjunctivalhaemorrhage
Severelywrinkled/dislodged flap
Interface debris
Punctate epithelialkeratopathy
Diffuselamellarkeratitis
Interface haze
Infectiouskeratitis
Regression of refractiveeffect
Epithelialingro~_h
Progressive keratolysis (focalmelt)
Corneal ectasia
Contact Lens and Anterior Eye

5. Refractive surgery from an optometric perspective
JP Craig
38
pupil centre. In terms of satisfaction post-operatively, all
patients felt that they had fully understood the
procedure prior to surgery, and all except one was very
happy with their speed of visual recovery following
surgery. This patient was awaiting retreatment for
myopic regression and, ultimately, was delighted with
their result. Ninety-four per cent of subjects felt that
they had achieved the goals for which they had
undergone the surgery and all but one subject felt that
their quality of life had improved. It is noteworthy that
two of the three subjects (including the dissatisfied
patient mentioned above) who did not feel that their
goals had been realised were awaiting retreatment and
both recorded their unaided visual outcome as 'excel-
lent' on a four point scale: poor, average, good, or
excellent, following an enhancement procedure.
Thus, overall, this study reported a very high level of
functional improvement, a perceived improvement in
quality of life, and consistently high levels of post-
operative satisfaction, across a range of visual function
parameters. Given that more than 31% of the eyes did
not achieve 6/12 or better unaided, this may be
considered surprising. The high levels of satisfaction
reported in this anonymous study are believed to be due
in part to the extensive preoperative counselling and
written information given to subjects, which helps to set
realistic expectations of the surgery. Indeed, the
preoperative counselling in the Unit has been refined
on the basis of an extensive study determining the
reasons why patients seek LASIK treatment. It has been
established, from a previous study which compared
psychological aspects of patients attending an optometry
practice for a contact lens assessment to those consult-
ing a laser unit for an excimer laser PRK assessment,
that patients seeking PRK cannot be considered
conspicuously neurotic, nor driven to refractive surgery
because of low self-esteemY It is therefore important
that the eye-care professional understands the reasons
for patients seeking LASIK, in order to be able to best
counsel patients, prior to surgery. In a further study at
the University of Dundee, 21 cards, each printed with a
potential reason for choosing to undergo LASIK for
myopia, together with three blank cards for subjects to
include any additional motives, were posted to 71
patients (detailed in Table 4) who had undergone
myopic LASIK.28These choices were ranked by each
patient, in order of personal importance, and were
returned for analysis.
Table 4. Characteristics of patients enrolled in study to
investigate reasonsfor seeking LASIK treatment for myopia.
Patient characteristics and responses
18 males, 37 females
41.7+ 9.3 years
-9.26_+4.58 DS
Gender
Mean age (+ standard deviation)
Mean pre-operative refraction
(+ standard deviation)
Response rate to questionnaire 77.5%
Contact Lens and Anterior Eye
Reasons for Seeldng LASIK
The reasons ranked within the top five by each patient
were considered to be representative of their main
reasons for undergoing LASIK for myopia. As might be
expected, primary motives included the desire to
improve unaided social vision (for example, being able
to get about in daily living, without spectacle or contact
lens correction) and the desire to be free from
spectacles or contact lenses. Surprisingly, however,
another very important factor (ranked within the top five
reasons by 65% of respondents) was intolerance to
spectacles or contact lenses. Almost 70% of subjects
recorded one of these three reasons as their main
motive for undergoing this treatment. The inconveni-
ence of spectacle or contact lenses, and the desire to
improve unaided vision for sports and leisure activities,
were also ranked highly.
Another interesting finding, reflecting, perhaps, the
mean magnitude of refractive error treated by LASIK in
the current group, was the relative unimportance of
cosmesis, or self-confidence. Patients with such high
levels of myopia, are warned that they are likely to be
left with a residual refractive error which may necessi-
tate continued spectacle or contact lens wear, albeit, of
lower power. Those patients, for whom cosmetic
appearance is the sole motive, are often discouraged
from undergoing surgery, for fear of their expectations
not being realised. This is supported by the finding that
the individuals with lower preoperative refractive errors
(~<10.00 DS) considered freedom from spectacles to be
significantly more important than did those with higher
refractive error (>10.00 DS) (P<0.05). Males, unex-
pectedly, were found to be significantly more keen to be
free from spectacles or contact lenses than females,
whilst higher intolerance levels to these modes of
refractive correction were claimed by females (P< 0.05
in both cases). The reason for the latter finding is
unknown, but might reflect a possible higher incidence
of contact lens-induced dry eye reported by females
than by males, in the clinical setting. The results of this
study have helped the individuals involved in the pre-
operative counselling of prospective LASIK patients, to
establish most effectively the individual patient's incen-
tives for undergoing surgery. With this knowledge,
more realistic expectations can be set, and patient
satisfaction can be maximised. It should be noted that
approximately 50% of patients attending the Corneal
Diseases and Excimer Laser Research Unit in Dundee
were advised against undergoing refractive surgery, not
only as a result of unsuitability for the technique, but
more often as a result of high patient expectations which
could not realistically be guaranteed.
Scope for Research
Although subjective aspects of refractive surgery out-
come have been a primary research interest for the
author, many aspects of refractive surgery, beyond
visual acuity, lend themselves to objective analyses.
New generation 3-D slit-scanning topographers such as

6. Refractive surgery from an optometric perspective
JP Craig
the Orbscan, non-invasively provide the user with a full-
cornea pachymetry map, based on the difference
between anterior and posterior corneal heights. This
has clear benefits over the current gold standard,
ultrasound pachymetry, which requires topical anaes-
thesia and direct contact of the probe with the corneal
epithelium. In a large study of topography, a comparison
between these methods of establishing central corneal
thickness was undertaken. Central corneal thickness
was compared in a group of 101 normal eyes and in a
group of 30 eyes post-LASIK, and it was found that the
Orbscan tended to overestimate, on average, for the
normal eyes, but underestimate, on average in the post-
LASIK eyes compared to ultrasound pachymetry.29 It
was also associated with significant variability such that
the results from the two techniques cannot be con-
sidered clinically interchangeable. The higher variability
experienced in the post-LASIK eyes is believed to be
related to altered corneal composition in the region of
the LASIK flap interface affecting calculations which
assume constant refractive index for the cornea.
It is an unfortunate consequence of the high profile of
refractive surgery in the media that the exciting
phototherapeufic options of excimer laser techniques
have been overshadowed. The author has been involved
in a number of studies using PTK to treat superficial
corneal disease, particularly recurrent corneal erosions
and superficial corneal opacity, in addition to therapeutic
refractive techniques for iatrogenic refractive errors. In
particular, LASIK seems to have an important r61e in
dealing with post-corneal transplantation ametropia
where, as a general rule, up to 10% of individuals post-
graft might benefit greatly from LASIK correction of
ametropia not readily corrected by contact lenses? ° In
comparison with incisional techniques which are cur-
rently used to treat post-transplantation astigmatism,
LASIK appears equally successful, but has the added
benefit of being able to treat the myopia, such that the
spherical equivalent can be reduced to as near zero as
possible. Therefore, although more technically difficult
than LASIK on previously unoperated corneas, this
success, in combination with the rapid rehabilitation and
absence of the haze associated with comparable correc-
tions by PRK, will ensure a r61e for LASIK in this area of
transplantation surgery for the foreseeable future.
Conclusion
In conclusion, refractive surgery today cannot be 16
considered an unconditional panacea for the permanent
correction of ametropia. For the outcome to be
17
optimised, the risks and benefits of the ever-changing
face of refractive surgery must be fully assessed. This
requires a highly professional and motivated team, 18
within which the r61e of the optometrist is increasingly
expanding. 19
Acknowledgements
Dr JP Craig was supported, in part, by an unrestricted
grant from the Speed-Pollock Memorial Research Trust.
Individuals are acknowledged for their contribution to
the work by citation in the reference section. I would
like to thank Professor CNJ McGhee, PhD, FRCOphth
for assistance in preparing the manuscript.
Address for Correspondence
Dr JP Craig, Discipline of Ophthalmology, University of
Auckland, Private Bag 92019, Auckland 1001, New
Zealand. E-mail: jp.craig@auctdand.ac.nz
REFERENCES
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