Scleral surgery for the treatment of presbyopia: where are we today?
Hipsley et al. Eye and Vision
Scleral surgery for the treatment of presbyopia: where are we today?
Karolinne M. Rocha
Presbyopia corrections traditionally have been approached with attempts to exchange power, either at the cornea or the lens planes, inducing multifocality, or altering asphericity to impact the optical system. Treatments that affect the visual axis, such as spectacle and contact lens correction, refractive surgeries, corneal onlays and inlays, and intraocular lenses are typically unable to restore true accommodation to the presbyopic eye. Their aim is instead to enhance 'pseudoaccommodation' by facilitating an extended depth-of-focus for which vision is sufficient. There is a true lack of technology that approaches presbyopia from a treatment based or therapy based solution, rather than a 'vision correction' solution that compromises other components of the optical system. Scleral surgical procedures seek to restore true accommodation combined with pseudoaccommodation and have several advantages over other more invasive options to treat presbyopia. While the theoretical justification of scleral surgical procedures remains controversial, there has nevertheless been increasing interest and evidence to support scleral surgical and therapeutic approaches to treat presbyopia. Enormous progress in scleral surgery techniques and understanding of the mechanisms of action have been achieved since the 1970s, and this remains an active area of research. In this article, we discuss the historic scleral surgical procedures, the two scleral procedures currently available, as well as an outlook of the future for the scleral surgical space for treating presbyopia.
Scleral surgery; Presbyopia; Accommodation; Presbyopia treatment
Presbyopia means “old eye”, which is traditionally described
as the gradual loss of the eye’s ability to focus on near
objects due to the loss of elasticity of the crystalline lens [
Recent research, however, has demonstrated that as the eye
ages there are numerous changes in other tissues of the eye
such as the vitreous membrane, peripheral choroid, ciliary
muscle, scleral connective tissue, and zonules, to name a
few, which may contribute to the dysfunction of
]. A significant consequence of aging is a
progressive loss of accommodative ability, which affects an
estimated half a billion people worldwide . The average
age of onset is 42 after which a significant and progressive
decline is seen through the next two decades. A teenager
has about 13 diopters (D) of subjective accommodation,
whereas an average 40-year-old retains approximately 6 D
and a 50-year-old 2 D [
]. According to Donder’s Curve, we
lose almost 0.25 D per year throughout our 40s and 50s with
an average subjective accommodation ability of 1 D by the
age of 60 [
]. In wealthy nations, presbyopia correction or
treatment is convenience and quality of life factor. However,
in 3rd tier economic regions of the world, it is a
socioeconomic burden contributing to the World Health
Organization (WHO) statistics of the blindness of
uncorrected refractive errors and presbyopia [
]. Lack of
resources, ophthalmologists, and awareness create a culture in
which the manifestation of presbyopia creates a quality life
crisis with near and intermediate vision loss up to 3 D
without remedy [
]. In these areas, presbyopia becomes a
disability and reason to leave the workforce in society.
Presbyopia has an enormous impact on the gross domestic
product (GDP), reducing global GDP by approximately
USD 25 billion .
Presbyopia is typically defined following the Hemholtz
theory of accommodation, wherein the loss of elasticity of
the lens substance causes a reduction in accommodative
ability, resulting in presbyopia [
]. As per this theory,
presbyopia can be treated with spectacles, contact lenses,
corneal surgery, or intraocular lenses. Spectacle and
contact lens use are the conventional treatments, [
neither of these attempt to restore true accommodation to
the presbyopic eye.
There are limitations to treating the real cause of
presbyopia or the loss of accommodative ability of the lens to
dynamically change focus power. Firstly, the early attempts to
address presbyopia were to exchange either the power in
the cornea or the lens to achieve multifocality or changes
in asphericity. Corneal presbyopic correction procedures,
such as presbyLASIK, attempt to create a multifocal cornea
by manipulating the optical properties of the eye,
asphericity, and inducing higher-order aberrations, [
intraocular lens (IOL) replacement may include multifocal
and aspheric lenses. These vision correction procedures
may compromise distance vision and degrade binocularity
and stereopsis [
]. Performing these corrections with
surgical intervention carries additional risks of regression,
scarring, and night vision problems [
]. These treatments
also only aim to enhance ‘pseudoaccommodation’ by
facilitating an extended depth-of-focus for which vision is
] rather than restoring true accommodation and
True accommodation is the ability of the eye to modify
the focal length of the lens to see objects clearly when
changing focus from distance to near. During true
accommodation the ciliary muscles contract, releasing
tension in the zonules, which allows the lens to return to
its more natural convex shape [
]. Moreover, the ciliary
muscles, the zonular tensions on the lens, and the role
of the elastic choroid, in both the pre-stretch,
disaccommodated state and accommodated states, all play
complex roles in the amount of accommodative range and
biomechanical functionality of the entire
accommodation complex [
]. The biomechanics of this functional
anatomy is directly proportional to the amount of
accommodative amplitude and the central optical power
that can be generated from the dynamic accommodative
]. Moreover, as we age, there is resultant
biomechanical dysfunction that is manifested with
presbyopia creating a dysadaptation of binocularity, which
further complicates the visual disturbances experienced
with progressive presbyopia [
There have also been strides to classify the treatment
paradigm for presbyopia, which assists the ophthalmic
surgeon to determine the stages of classification of presbyopia
and allow a more evidence-based decision-making tree for
the treatment of presbyopia. Dysfunctional Lens Syndrome
(DLS) has been described by George Waring IV and
colleagues as a deterministic model to characterize the aging
]. In DLS Stage I the lens becomes more rigid and
less flexible, corresponding with presbyopia. In DLS Stage
II contrast sensitivity loss, increased higher-order
aberrations and light scatter often affect night vision function. In
DLS Stage III the lens clouding is significant, and severely
impacts daily activities; this stage corresponds with
cataracts. Scleral surgeries are useful in as much as they can
still effectuate the molding of the lens. To achieve this, the
lens must be clear and void of opacities and age-related
damage. The most likely candidate to achieve the most
improvements with scleral surgeries would be a person who
is classified as having Stage I DLS. However, candidates
who are in Stage II have also received benefits from scleral
procedures. Therefore, the relationship of DLS as it
correlates to scleral procedure outcomes requires further
investigation and remains an open question.
Despite the different treatment options to restore
pseudoaccommodation, there remains a need for treatments to
restore true accommodation combined with
pseudoaccommodation to the presbyopic eye. Scleral surgical procedures
have the potential to fulfill this requirement and have
several advantages over other more invasive options to treat
presbyopia. Firstly, scleral procedures deviate from the
paradigm of ‘vision correction’ (rectifying visual acuity
deficits) to a therapeutic approach; aiming to restore static
and dynamic physiological function in the eye. The risk of
vision loss is lower, as the cornea, visual axis, and the native
crystalline lens are not involved in these procedures, which
allows scleral procedures to be performed after or in
combination with other corrective methods, such as cataract
surgery. While their theoretical justification may be
], there has nevertheless been increasing interest
in scleral surgery to treat presbyopia. In this article, we will
discuss the historical scleral surgical procedures and the
two procedures currently available to treat presbyopia.
Scleral surgical procedures, as a treatment for presbyopia,
were followed from the surgical myopia treatments of
Fyodorov in the 1970s. Fyodorov treated myopia with
radial keratotomy (RK) - radial or spoke cuts through the
]. Thornton later expanded RK surgery to the
sclera, using a procedure known as anterior ciliary
sclerotomy (ACS) [
]. In ACS, radial incisions are not made
in the cornea, but in the sclera overlaying the ciliary
]. The aim was to increase the space between
the lens and the ciliary muscle, tightening the zonules and
increasing accommodative ability [
was observed to improve slightly with ACS. However, a
myopic shift of 0.5 D was also seen [
accommodative improvements were also short-term, with 0.8 D of the
amplitude of accommodation remaining after 12 months
]. To reduce this regression, Fukasaku used silicone
implants in conjunction with ACS [
]. These treatment
options are no longer available.
Scleral implants are based on the accommodation model
described by Schachar and colleagues [
]. This model
describes a decreasing gap between the lens perimeter and
the ciliary ring with age, due to a combination of
anatomical changes, as the cause of presbyopia. This model
remains controversial, as it differs from the widely accepted
Hemholtz model of accommodation,  however it is
supported by experimental evidence [
Schachar and colleagues used scleral implants in an
attempt to increase the area between the ciliary muscle
and the sclera to restore accommodation. The first
instances used poly[methyl methacrylate] (PMMA) rod
implants to expand the sclera and were referred to as
‘scleral expansion bands’ [
]. Scleral expansion bands
(SEBs) did achieve some success in restoring
accommodation but were ultimately retired due to mixed results and
low patient satisfaction . There were also events of
anterior ischemia, which was not an acceptable risk for an
‘elective procedure.’ This lead to a general decrease in
support and interest from the ophthalmology community
and almost complete abandonment of the idea that scleral
procedures were viable to treat presbyopia [
Despite early failures, using implants to expand the area
between the sclera and the ciliary muscle is still an active
area of research. The VisAbility Micro-Insert scleral implant
(Refocus Group, Dallas, TX, USA), an updated version of
the PresView (Refocus Group, Dallas, TX, USA), remains
the only scleral implant with the CE mark and is currently
undergoing FDA clinical trials [
]. The procedure uses four
PMMA injection molded implants, each about the size of a
grain of rice (Fig. 1). The implants are placed about
30004000 μm from the limbus and to a depth of 400 μm within
the sclera. Patients are placed under monitored anesthesia
care for the duration of the procedure, approximately 1 h
bilaterally. The implants aim to lift the sclera and the ciliary
muscle to tighten the zonular fibers holding the lens [
Results from a previous 24-month clinical trial with the
VisAbility Micro-Insert were presented in 2013 [
The authors subjectively evaluated the visual function of 80
patients after 24 months using a questionnaire. The
participants were asked to describe their unaided vision as
‘excellent,’ ‘acceptable,’ or ‘poor,’ pre and postoperatively. The
percentage of patients reporting at least ‘acceptable’ vision
after 24 months was 73% overall, and 99% for distance tasks
]. Preoperatively, 4% of patients reported at least
‘acceptable’ vision when reading newspapers, which
improved to 76% of patients 24 months postoperatively [
]. Approximately 83% of patients were able to complete
near tasks (such as reading newspapers, prices, and
medicine labels) without using reading spectacles [
Distance-corrected near visual acuity (DCNVA) data from
the same clinical trial were presented in 2014 [
results showed that 93% of patient eyes had DCNVA of 0.3
logMAR (20/40 Snellen) or better [
While the early VisAbility clinical trial results seem
promising, there are substantial risks involved for patients
undergoing this procedure. Anterior segment ischemia
(ASI) due to mechanical vascular compression from the
implant can occur, as can subconjunctival erosion,
moderate to severe subconjunctival hemorrhage, implant
infection, and endophthalmitis. There is also a significant risk
that the implants may become displaced [
]. An early US
Federal Drug Administration (FDA) study showed that
about 75% patients with the first generation of the now
VisAbility Micro-Insert implant had at least one implant
move or displace [
]. Other treatment options exist that
may be safer for patients.
Scleral laser excision
Scleral laser excision procedures as a treatment for
presbyopia began with Lin in 1998 [
]. Lin argued that ACS was
unsuccessful due to the rapid healing of the sclera and
proposed instead to ablate nearly the full thickness of the
]. Termed laser presbyopia reversal (LAPR), Lin’s
surgical procedure involved radial sclerectomy with an
erbium-doped yttrium aluminum garnet (Er:YAG) laser.
Excisions were performed to a depth of 500-600 μm, with a
length of approximately 4500 μm, and a width of
600700 μm [
]. Results after 12 months showed 2 D of
subjective accommodation. However, this may be explained by
the decrease in anterior chamber depth causing a myopic
shift. This treatment option is no longer available.
Scleral laser micro-excision
Scleral laser anterior ciliary excision (LaserACE, Ace Vision
Group, Newark, CA, USA) is the only scleral laser
Fig. 6 A representative figure of the depth of focus (DoF). Visual Strehl
ratio based upon the optical transfer function (VSOTF) is computed as a
function of defocus using a through-focus curve
excision procedure currently available and has recently
completed phase III clinical trials [
]. LaserACE is not based on
the Schachar model but instead follows from VisioDynamics
theory, which is a biomechanical model for the aging eye
]. VisioDynamics theory contends that presbyopia is not
a refractive error or the loss of accommodation solely, but
rather an aging disease limited by structural/mechanical,
extracellular and intracellular, and physiological aspects of
the eye. It argues that as the eye ages, the connective tissues
within begin to change and impact ocular biomechanical
efficiency. This, in turn, influences visual function and ocular
physiology including ocular metabolic efficiency, and ocular
biotransport. A better approach to treat presbyopia may be
to address these age-related changes rather than to increase
scleral diameter across the globe since increasing scleral
diameter could induce unwanted biomechanical effects [
Given the complexity of the accommodation mechanism,
the Helmholtz theory is an incomplete explanation for
presbyopia. Recent evidence has highlighted aging-related
changes in the vitreous membrane, peripheral choroid, ciliary
muscle, and zonules [
]. The sclera itself is known to be
affected by age, bowing inward . Ocular rigidity and
increasing stiffness of the zonular apparatus may also further
contribute to presbyopia [
]. Proprioceptors in the
vitreous zonular system have also been found to contribute to
the loss of accommodation with age . Given the many
suggested contributions to the loss of accommodation,
presbyopia may be better described by age-related changes in
resting muscle apex thickness and accommodative lens
thickening together [
]. LaserACE was thus designed to both
alter the biomechanical properties of ocular tissue and
improve the efficiency of the accommodation apparatus (Fig. 2).
The LaserACE surgical technique is shown in Fig. 3.
In brief, an Er:YAG laser is used to create a matrix array
of micro-excisions (micropores, 600 μm in diameter) in
the sclera, to a depth of 85-90% the thickness of the
sclera (approximately 500-700 μm). The micro-excisions
are done in four oblique quadrants of the eye over three
critical zones of anatomical and physiological
44, 46, 49
]. The procedure is performed under
topical anesthesia and takes approximately 10 min per
eye. The 3 critical zones of anatomic and physiologic
importance are as follows and range from 0.5 mm up to
6.0 mm from the anatomical limbus (AL): 1) the scleral
spur at the origin of the ciliary muscle (0.5 - 1.1 mm
from AL); 2) the mid ciliary muscle body (1.1 – 4.9 mm
from AL); and 3) insertion of the longitudinal muscle
fibers of the ciliary, just anterior to the ora serrata at the
insertion of the posterior vitreous zonules (4.9 – 5.5 mm
from AL) [
44, 46, 49
]. Within the matrix, there are areas
of both positive stiffness (remaining interstitial tissue)
and negative stiffness (removed tissue or micropores).
The differential stiffness created in these areas increases
the plasticity and compliance of the scleral tissue during
contraction of the ciliary muscles, and thus improve the
efficiency of the accommodation apparatus.
The primary risk factor with LaserACE is accidental
micro-perforation of the sclera. This can be mitigated with a
collagen biomatrix. If a micro-perforation does occur,
intraocular pressure may be temporarily lowered. Non-persistent
mild subconjunctival hemorrhages are also a risk factor.
Data from a 24-month postoperative follow-up of the
LaserACE clinical study were published in 2017 and
show promising results [
]. Visual acuity at distance
(4 m), intermediate (60 cm), and near (40 cm) was
measured using standard Early Treatment Diabetic
Retinopathy Study (ETDRS) charts, and statistical analysis
was done using an ANOVA and Tukey HSD test
(Fig. 4). Monocular uncorrected near visual acuity
(UNVA) improved from + 0.36 ± 0.20 logMAR
preoperatively, to + 0.25 ± 0.18 logMAR (p < 0.00005) at
24 months postoperatively, and binocular DCNVA
improved from + 0.21 ± 0.17 logMAR preoperatively, to +
0.11 ± 0.12 logMAR at 24 months (p = 0.00026).
DCNVA was also 0.2 logMAR (20/32 Snellen) or better
in 83% of patients at 24 months postoperatively [
Stereoacuity (Randot stereoscopic test) also improved,
averaging 58.8 ± 22.9 s of arc at 24 months
postoperatively compared to 75.8 ± 29.3 s of arc preoperatively
]. There were no complications such as loss of
bestcorrected visual acuity, cystoid macular edema, or
persistent hypotony. Patients surveyed using the CatQuest
9SF Survey, [
] indicated reduced difficulty in areas of
near vision, such as seeing when doing handwork, reading
newsprint text, and seeing prices while shopping (Fig. 5).
Patients indicated overall satisfaction with the procedure
and their mean satisfaction scores significantly
improved from − 1.00 (SE = 0.22) preoperatively, to + 0.33
(SE = 0.36) at 24 months postoperatively (p = 0.000016).
With advances in diagnostic techniques, such as
wavefront aberrometry, it is now possible to objectively
assess visual performance. Visual Strehl of the Optical
Transfer Function (VSOTF) is an optical wavefront
error-derived metric that predicts patient visual acuity
]. It is defined as [
A VSOTF of 0.12 correlates to approximately 0.2
logMAR, while a VSOTF of 0.3 correlates to approximately 0
]. VSOTF can be computed as a function of
defocus by creating a through-focus curve. For example, in
Fig. 6 VSOTF was determined using a ray-tracing
aberrometer (Tracey Technologies, Dallas, TX, USA). A
through-focus curve and VSOTF can be used to determine
the objective depth of focus (DoF). A certain threshold of
image quality was selected, 50% of the maximum VSOTF
as used previously, [
] then the diopter range between the
two points on the curve at the threshold value gives the
objective DoF (Fig. 6).
Ray-tracing aberrometry objectively compares
refraction and higher order aberrations at a distance
and near target and can be used to determine true
accommodation, effective range of focus (EROF), and
pseudoaccommodation. The EROF is the range of
focus with acceptable blur and includes both the true
accommodation and pseudoaccommodation. Figure 7
is an example through focus curve of a young person
who can still demonstrate true accommodation.
Figure 7 shows near (40 cm; red) and distance (4 m;
green) through-focus curves from two different
wavefront scans for a 32-year-old eye. Under the
throughfocus curves is the ray-tracing refraction at the peak
of each curve. Additionally, Fig. 7 shows the EROF,
3.17 D, which is the difference in diopters between
the near and distance DoF curves at the threshold
value (50% of the VSOTF). The true accommodation
is equal to the difference in the spherical equivalent
of ray-tracing refraction for the distance and near
DoF curves (measured from curve peak to curve
peak). In this 32-year-old eye, this is equal to [− 0.38
D minus (− 2.57 D)] or 2.19 D. The
pseudoaccommodation is the EROF minus the true accommodation,
or 0.98 D in this exam. Alternatively, Fig. 8 shows
two through-focus curves from two different
wavefront scans (near in red and distance in green) from
a representative 59-year-old presbyopic patient. In this
example, the EROF is 1.02 D, the true
accommodation is minor at 0.03 D, and the
pseudoaccommodation is 0.99 D, which is a typical amount of
physiological accommodation that we would expect to
find in a person of this age with advanced presbyopia.
In another study [
], ray-tracing aberrometry was
used to produce through focus curves from two different
scans to objectively evaluate the amount of combined
pseudoaccommodation and accommodation in
presbyopes, and their visual performance, of patients who were
the area under the contrast sensitivity‐weighted optical transfer function
VSOTF ¼ the area under the contrast sensitivity‐weighted optical transfer function for a diffraction‐limited eye
treated with LaserACE procedure up to 13 years
postoperatively. Patient demographics and visual performance
are shown in Table 1. Figure 9 shows the DoF for near
(red) and distance (green) and the EROF measurements
for one postoperative patient eye. The VSOTF, DoF,
EROF, and objective accommodation were determined
as described above and shown in Table 1. Pupil
contraction can enhance DoF measurements. Figures 7, 8 and 9
show that patient pupils did contract for near
observation. Since LaserACE does not affect pupil contraction,
this will occur during both preoperative and
postoperative accommodation measurements and can be
eliminated by comparing the ranges of accommodation. The
effective range of focus averaged 1.56 ± 0.36 D for all
patient eyes (n = 6), which was higher than preoperative
clinical accommodation averaging 0.92 ± 0.61 D.
Patients’ DoF also increased by 0.84 ± 0.74 D compared to
preoperative DoF. Up to 13 years postoperatively, true
accommodation and pseudoaccommodation averaged
0.23 ± 0.24 D and 1.33 ± 0.38 D respectively. A one
quarter diopter increase in true accommodation corresponds
to a one-line improvement in near visual acuity.
Pseudoaccommodation also improved by approximately
onequarter diopter. Up to 13 years postoperatively, the 0.5 D
of restored accommodation after LaserACE was clinically
significant, and there was a corresponding increase in
UNVA. UNVA was 20/20 or better in 66% of patient eyes
up to 13 years postoperatively. Post-operative uncorrected
distance visual acuity was 20/40 or better in all patient
eyes, while 83% of eyes had + 1.25 D of sphere or greater.
It is possible that these patients may have latent hyperopia,
and thus the restored accommodative ability after
LaserACE can correct a small degree of the hyperopia in these
patients improving their distance vision [
studies have shown a similar result in hyperopic patient
eyes after LaserACE [
]. Patient postoperative visual
acuities are shown in Table 2.
DCNVA for all patients remained at 0 logMAR (20/
20 Snellen) or better up to 13 years postoperatively.
It is interesting to note that these patients all had
prior laser vision correction (LVC) to correct their
distance refraction to emmetropia before LaserACE.
Since LaserACE does not touch the visual axis, these
patients were able to achieve efficient near visual
performance dynamically through combined
accommodation and pseudoaccommodation without affecting
their previous LVC.
LaserACE has many benefits compared to other
presbyopia treatments. Patients experience an increased quality
of life by decreasing their dependence on spectacles and
LaserACE= laser anterior ciliary excision; UDVA= uncorrected distance visual acuity; UIVA= uncorrected intermediate visual acuity; UNVA= uncorrected near visual
acuity; CDVA= corrected distance visual acuity; DCIVA= distance corrected intermediate visual acuity; DCNVA= distance corrected near visual acuity
contact lenses. The optical elements of the eye (cornea,
lens, anterior chamber, and retina) remain untouched,
unlike corneal surgical procedures. Asphericity of the eye is
not manipulated, no multifocality is introduced, and the
resting geometry of the eye is maintained. Furthermore,
there is a physiological change in the eye improving both
true accommodation and pseudoaccommodation, as well
as expanding EROF. Increased dynamic movement of the
lens helps facilitate ocular biotransport as well as visual
function. Decreasing ocular rigidity may not only affect
the development of presbyopia but also may influence the
development of glaucoma and age-related macular
degeneration, thus improving the longevity of the eye organ
]. Although not available yet for North American
patients, LaserACE surgery has the potential to expand
EROF, restore true accommodation combined with
pseudoaccommodation, and improve the quality of life in
presbyopes. LaserACE is being further investigated outside of
the United States.
While studies of scleral surgery as a treatment for
presbyopia are ongoing, we wish to stress the
importance of consistent data being collected, published, and
verified using randomized multicenter studies. These
studies will further clarify the role of scleral surgery and
associated technologies to the treatment of presbyopia.
In conclusion, scleral surgical procedures remain one of the
options to restore true physiological accommodation
combined with pseudoaccommodation, as well as improving
effective range of focus in presbyopes. Tremendous progress
in scleral surgery techniques and understanding of the
mechanisms of action have been achieved since the 1970s,
and this remains an active area of research. New research
has identified other extralenticular factors, in addition to
lens stiffness, which contributes to the loss of
accommodation with age [
]. Utilizing this new understanding of
recent research, scleral surgical procedures may be able to
expand far beyond the first RK surgeries and PMMA rods
used by Thornton, and Schachar and colleagues. Moreover,
new diagnostic and imaging technologies allow more
quantification of the results and mechanisms of these
procedures such as ray-tracing, very high-frequency
ultrasound biomicroscopy (VHF UBM), and high definition
optical coherence tomography (HD OCT). Upon further
advancement of these technologies, as well as more
extensive research, a deeper understanding of this complex
mechanism in the eye should be illuminated. Scleral
surgeries have the potential to become the gold standard for early
presbyopes who still have a clear lens due to their low
invasiveness and off – optical axis appeal. This affords the
potential candidates no restriction in choosing a variety of
vision correction solutions for a “lifetime vision plan”, a
concept that was popularized by Professor Emeritus,
George O. Waring III, MD. Dr. Waring III emphasized a
need for a paradigm shift from interfacing refractive
patients in the scope of their vision needs through their
lifetime instead of a one-time surgical candidate.
Availability of data and materials
The data regarding LaserACE presented in this review is available from the
corresponding author upon request.
BH and AMH performed the literature review, meta-analysis, and were both
significant contributors to the writing of the manuscript. KMR performed the
data collection, analysis, and critical evaluation of the manuscript. All authors
read and approved the final manuscript.
Ethics approval and consent to participate
Data presented regarding LaserACE were obtained from IRB monitored and
registered international clinical pilot studies (Trial Registration: NCT01491360),
which followed the tenets of the Declaration of Helsinki.
Consent for publication
The LaserACE patients provided written consent for imaging and release of
personal identifying information including medical record details.
AMH reports personal fees and non-financial support from Ace Vision Group
Inc. during the conduct of the study. In addition, Dr. Hipsley has a patent
7,871,404 issued to Ace Vision Group Inc., a patent 8,348,932 issued to Ace
Vision Group, Inc., a patent 20,150,157,406 pending to Ace Vision Group, Inc.,
a patent 20,140,316,388 pending to Ace Vision Group, Inc., a patent
20,140,163,597 pending to Ace Vision Group, Inc., a patent 20,120,165,849
pending to Ace Vision Group, Inc., a patent 20,110,190,798 pending to Ace
Vision Group, Inc., a patent 20,080,058,779 pending to Ace Vision Group, Inc.,
and a patent 20,070,016,175 pending to Ace Vision Group, Inc.
BH reports personal fees from Ace Vision Group Inc. during the conduct of
1Ace Vision Group Inc, 39655 Eureka Drive, Newark, CA 94560, USA. 2Sengi
Data, Cambridge, ON, Canada. 3Storm Eye Institute, Medical University of
South Carolina, Charleston, SC, USA.
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