Note: Descriptions are shown in the official language in which they were submitted.
AMETROPIA TREATMENT TRACKING METHODS AND SYSTEM
CROSS-REFERENCE TO RELATED APPLICATIONS
100011 This patent application claims the benefit of United States
Provisional
Patent Application Serial No. 62/489,666 filed on April 25, 2017.
BACKGROUND OF THE INVENTION
Field of the Invention
100021 The present invention relates to methods and a system for
determining
myopia progression in an individual by predicting changes in the axial length
of the
individual's eye based on that individual's past refractive rate of change,
and for
recommending a myopia control treatment option for controlling refractive
progression based on the predicted axial elongation.
Discussion of the Related Art
100031 Common conditions which lead to reduced visual acuity include
myopia
and hyperopia, for which corrective lenses in the form of spectacles, or rigid
or soft
contact lenses, are prescribed. The conditions are generally described as the
imbalance between the length of the eye and the focus of the optical elements
of the
eye. Myopic eyes focus light in front of the retinal plane and hyperopic eyes
focus
light behind the retinal plane. Myopia typically develops because the axial
length of
the eye grows to be longer than the focal length of the optical components of
the eye,
that is, the eye grows too long. Hyperopia typically develops because the
axial
length of the eye is too short compared with the focal length of the optical
components of the eye, that is, the eye does not grow long enough.
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[0004] Myopia has a high prevalence rate in many regions of the world. Of
greatest concern with this condition is its possible progression to high
myopia, for
example, greater than five (5) or six (6) diopters, which dramatically affects
one's
ability to function without optical aids. High myopia is also associated with
an
increased risk of retinal disease, cataract, glaucoma, and myopic macular
degeneration (MMD; also known as myopic retinopathy), and may become a leading
cause of permanent blindness worldwide. For example, MMD has been related to
refractive error (RE) to a degree rendering no clear distinction between
pathological
and physiological myopia and such that there is no "safe" level of myopia.
[0005] Corrective lenses are used to alter the gross focus of the eye to
render
a clearer image at the retinal plane, by shifting the focus from in front of
the plane to
correct myopia, or from behind the plane to correct hyperopia, respectively.
However,
the corrective approach to the conditions does not address the cause of the
condition, but is merely prosthetic or intended to address symptoms.
[0006] Most eyes do not have simple myopia or hyperopia, but have myopic
astigmatism or hyperopic astigmatism. Astigmatic errors of focus cause the
image of
a point source of light to form as two mutually perpendicular lines at
different focal
distances. In the following discussion, the terms myopia and hyperopia are
used to
include simple myopia and myopic astigmatism and hyperopia and hyperopic
astigmatism respectively.
[0007] Emmetropia describes the state of clear vision where an object at
infinity is in relatively sharp focus without the need for optical correction
and with the
crystalline lens relaxed. In normal or emmetropic adult eyes, light from both
distant
and close objects passing through the central or paraxial region of the
aperture or
pupil is focused by the crystalline lens inside the eye close to the retinal
plane where
the inverted image is sensed. It is observed, however, that most normal eyes
exhibit
a positive longitudinal spherical aberration, generally in the region of about
+0.5
Diopters (D) for a 5 mm aperture, meaning that rays passing through the
aperture or
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pupil at its periphery are focused +0.5 D in front of the retinal plane when
the eye is
focused to infinity. As used herein the measure D is the dioptric power,
defined as the
reciprocal of the focal distance of a lens or optical system, in meters.
[0008] The spherical aberration of the normal eye is not constant. For
example, accommodation (the change in optical power of the eye derived
primarily
through changes to the crystalline lens) causes the spherical aberration to
change
from positive to negative.
[0009] U.S. Patent No. 6,045,578 discloses that the addition of positive
spherical aberration on a contact lens will reduce or control the progression
of
myopia. The method includes changing the spherical aberration of an ocular
system
to alter the growth in eye length. In other words, emmetropization may be
regulated
by spherical aberration. In this process, the cornea of a myopic eye is fitted
with a
lens having increasing dioptric power away from the lens center. Paraxial
light rays
entering the central portion of the lens are focused on the retina of the eye,
producing
a clear image of an object. Marginal light rays entering the peripheral
portion of the
cornea are focused in a plane between the cornea and the retina, and produce
positive spherical aberration of the image on the latter. This positive
spherical
aberration produces a physiological effect on the eye which tends to inhibit
growth of
the eye, thus mitigating the tendency for the myopic eye to grow longer.
SUMMARY OF INVENTION
10010] A system, method and computer program product for estimating a
future axial elongation (change of length) of an eye of an individual and
using an
axial elongation value as an index of an individual's myopic progression.
[0011] The system is computer implemented and runs computer program
products having methods to predict an individual's eye growth, i.e., the axial
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elongation of an individual's eye, based on that individual's past myopia
progression
rate, and particularly, as a function of refractive change values detected for
that
individual over a past predetermined time period, i.e., a past progression
rate (e.g.,
over a past year) and other parameters.
[0012] The present invention thus may be used to determine an estimation
of a
refractive change of an individual over a past predetermined time and use this
information to be able to predict a value representing a change in axial
length of the
eye thereby allowing for estimation of myopia progression over a future period
of
time.
[0013] These results can help clinicians detect excessive eye growth at
an
early age, thereby facilitating decision-making with respect to interventions
for
preventing and/or controlling myopia.
[0014] In accordance with one aspect of the present invention, a computer-
implemented method for treating myopia of an individual is provided. The
method
comprises: receiving, via an interface at a computer, data relating to
refractive
change in a prior pre-determined time period for the individual from a
reference
timepoint; receiving, via the interface, data representing an age of the
individual and
data representing a current axial length value of the eye as measured at the
reference timepoint; calculating, by the processor, a future axial elongation
of the
eye as a function of the age of the individual, the current axial length value
of the eye
as measured at the reference timepoint, and the refractive change in the prior
pre-
determined time period; generating, an output indication of the computed axial
elongation of the eye via the interface, and using the output indication to
select a
myopia control treatment for the individual.
[0015] In one aspect, the computer-implemented method causes receipt at a
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computing device of data relating to past refractive changes for the
individual; and
calculates, from the past refractive changes data, a progression rate of
change of
refractive change for the individual. This computed rate of change is further
annualized to obtain the refractive change for a past year.
[0016] Based on the determined progression rate of change of refractive
changes for the individual over the past year, the computer-implemented method
calculates a future axial elongation of the eye as a value AAL according to:
AAL = a x RECIPY (D) - b x age + c x axial length ¨ d
[0017] wherein a, b and c are respective coefficients; d is a constant
value in
mm, RECIPY represents the refractive change in Diopters, age represents an
individual's age in years, and axial length is in mm.
[0018] Based on the computed AAL for an individual, the methods
implemented may recommend an ametropia control treatment, e.g., prescription
of
use of a myopia control ophthalmic lens, for example, or a myopia control
contact
lens, specific to that individual.
[0019] In accordance with another aspect of the present invention, there
is
provided a computer system for treating myopia of an individual. The system
comprises: a memory for storing instructions; and a processor coupled to the
memory, said processor running said stored instructions to: receive, via an
interface
at the server, data relating to refractive change in a prior pre-determined
time period
for the individual from a reference timepoint; receive, via the interface,
data
representing an age of the individual and data representing a current axial
length
value of the eye as measured at the reference timepoint; calculate a future
axial
elongation of the eye as a function of the age of the individual, the current
axial
length value of the eye as measured at the reference timepoint, and said
refractive
change in the prior pre-determined time period; generate an output indication
of said
computed axial elongation of the eye via the interface, and use said output
indication
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to select a myopia control treatment for said individual.
[0020] In a further aspect, there is provided a computer program product
for
performing operations. The computer program product includes a storage medium
readable by a processing circuit and storing instructions run by the
processing circuit
for running a method. The method is the same as listed above.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The foregoing and other features and advantages of the invention
will
be apparent from the following, more particular description of preferred
embodiments
of the invention, as illustrated in the accompanying drawings.
[0022] FIG. 1 depicts a computer-implemented system for estimating future
axial elongation of an eye of an individual;
[0023] FIG. 2 depicts a method employed for suggesting a treatment option
for
myopia based on an estimated future axial elongation of an individual's eye
according to one embodiment.
[0024] FIG. 3 shows a representative hardware environment for practicing
at
least one embodiment of the present invention.
DETAILED DESCRIPTION OF INVENTION
[0025] The present invention relates to methods and a system for tracking
an
individual's refractive error progression over time by estimating a future
axial
elongation (change of length) of an eye of an individual and using an axial
elongation
value as an index of an individual's myopic progression.
[0026] In one embodiment, a computer implemented system runs computer
program products having methods to predict an individual's eye growth, i.e.,
axial
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elongation of an individual's eye, based on that individual's past myopia
progression
rate as a function of refractive change values detected for that individual
over a past
predetermined time period, i.e., (e.g., over a past year), and other
parameters.
[0027] In accordance with another exemplary embodiment, the present
invention is directed to a method for estimating future myopic progression
based on a
predicted axial elongation of an eye of an individual, providing a treatment
option to
reduce, retard, eliminate and potentially reverse progression of myopia in
individuals.
100281 FIG. 1 depicts a computer-implemented system for estimating future
axial elongation of an eye of an individual and determining a myopia control
treatment. In some aspects, system 100 may include a computing device, a
mobile
device, or a server. In some aspects, computing device 100 may include, for
example,
personal computers, laptops, tablets, smart devices, smart phones, or any
other similar
computing device for receiving input data; for performing data analysis such
as one or
more of the method steps discussed herein, and for outputting data. The input
data
and output data may be stored or saved in at least one database 130. The input
and/or output data may be accessed by a software application 170 installed on
computer 100 [for example a computer in the office of an Eye Care Practitioner
(ECP)]; by a downloadable software application (app) on a smart device 121; or
by a
secure website 125 or web link accessible by a computer via network 99. The
input
and/or output data may be displayed on a graphical user interface of a
computer or
smart device.
100291 In particular, computing system 100 may include one or more
hardware
processors 152A, 152B, a memory 154, e.g., for storing an operating system and
application program instructions, a network interface 156, a display device
158, an
input device 159, and any other features common to a computing device. In some
aspects, computing system 100 may, for example, be any computing device that
is
configured to communicate with a web-site 125 or web- or cloud-based server
120
over a public or private communications network 99. Further, as shown as part
of
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system 100, historical data pertaining to individuals' refractive changes
captured from
clinicians' measurements and including associated myopia control treatments,
are
obtained and stored in an attached, or a remote memory storage device, e.g., a
database 130.
[0030] In the embodiment depicted in FIG. 1, processors 152A, 152B may
include, for example, a rnicrocontroller, Field Programmable Gate Array
(FPGA), or
any other processor that is configured to perform various operations.
Processors
152A, 152B may be configured to execute instructions as described below. These
instructions may be stored, for example, as programmed modules in memory
storage
device 154.
[0031] Memory 154 may include, for example, non-transitory computer
readable media in the form of volatile memory, such as random access memory
(RAM) and/or cache memory or others. Memory 154 may include, for example,
other
removable/non-removable, volatile/non-volatile storage media. By way of non-
limiting examples only, memory 154 may include a portable computer diskette, a
hard
disk, a random access memory (RAM), a read-only memory (ROM), an erasable
programmable read-only memory (EPROM or Flash memory), a portable compact
disc read-only memory (CD-ROM), an optical storage device, a magnetic storage
device, or any suitable combination of the foregoing.
[0032] Network interface 156 is configured to transmit and receive data
or
information to and from a web-site server 120, e.g., via wired or wireless
connections.
For example, network interface 156 may utilize wireless technologies and
communication protocols such as Bluetooth , WIFI (e.g., 802.11a/b/g/n),
cellular
networks (e.g., CDMA, GSM, M2M, and 3G/4G/4G LTE), near-field communications
systems, satellite communications, via a local area network (LAN), via a wide
area
network (WAN), or any other form of communication that allows computing device
100 to transmit information to or receive information from the server 120.
[0033] Display 158 may include, for example, a computer monitor,
television,
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smart television, a display screen integrated into a personal computing device
such
as, for example, laptops, smart phones, smart watches, virtual reality
headsets, smart
wearable devices, or any other mechanism for displaying information to a user.
In
some aspects, display 158 may include a liquid crystal display (LCD), an e-
paper/e-
ink display, an organic LED (OLED) display, or other similar display
technologies. In
some aspects, display 158 may be touch-sensitive and may also function as an
input
device.
[0034] Input device 159 may include, for example, a keyboard, a mouse, a
touch-sensitive display, a keypad, a microphone, or other similar input
devices or any
other input devices that may be used alone or together to provide a user with
the
capability to interact with the computing device 100.
[0035] With respect to the ability of computer system 100 for computing a
change in axial length of an individual's eye, the system 100 includes: a
memory 160
configured to store data relating to a current individual's past refractive
changes/errors, e.g., data received from a clinician over a defined period of
time,
e.g., a past year. In one embodiment, this data may be stored in a local
memory
160, i.e., local to the computer or mobile device system 100, or otherwise,
may be
retrieved from a remote server 120, over a network. The data relating to a
current
individual's past refractive changes may be accessed via a remote network
connection for input to a local attached memory storage device 160 of system
100.
[0036] In one embodiment, the computing system 100 provides a technology
platform employing programmed processing modules stored in a device memory 154
that may be run via the processor(s) 152A, 152B to provide the system with
abilities
for computing future axial elongation length of the eye of an individual based
on the
input set of historical refractive change data received for that individual.
[0037] In one embodiment, program modules stored in memory 154 may
include operating system software 170 and a software applications module 175
for
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running the methods herein that may include associated mechanisms such as APIs
(application programming interfaces) for specifying how the various software
modules
interact, web-services, etc. that are employed to control operations used to
carry out
the change in axial length computations. One program module 180 stored in
device
memory 154 may include a "RECIPY" calculator 190 for determining a value
("RECIPY") representative of a current individual's refractive change in a
past time
period, e.g., one year. From this RECIPY refractive rate of change value of
the
individual, a further program module 190 stored in device memory 154 may
include
program code providing the various data and processing instructions of an
algorithm
that is run by the processors to predict a change in axial length ("AL") value
for that
individual. Based on the predicted change in axial length ("AMU) value for
that
individual, a further module 195 may be invoked to recommend to a clinician,
the
individual, or any user, a treatment option(s) such as a type of myopia
contact lens,
that may be used for inhibiting or preventing refractive changes or reducing a
refractive progression rate for the individual.
10038] FIG. 2 depicts a computer-implemented method 200 run at system 100
for estimating future axial elongation of an individual's eye and for
suggesting a
treatment option for myopic patients based on an estimated future axial
elongation of
an individual's eye according to one embodiment. An individual may include
children
having an approximate age of 6 to 14. However, the methods herein could also
be
applied to younger children, older adolescents, or young adults.
100391 In one embodiment, the method at 205 receives data representing
the
refractive values measured for that individual over a period of time. For
example, the
system 100 of FIG. 1 receives from the memory data representing the refractive
change of an individual over a period of time. In one example, a period of
time may
be one or more years prior to a reference time point, e.g., a current day.
Further, at
210 the system of FIG. 1 receives characteristics about the individual
including at
least, the age of the individual. At 215, the system 100 receives the current
measure
of the axial length of the eye. If this data is not available, the clinician
or ECP may be
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prompted via a system display interface 158 to obtain or take a current
measurement
of the axial length of the individual's eye using ultrasonographic, partial
coherence
interfermetry, optical low-coherence reflectometry, swept-source optical
coherence
tomography or other measurement techniques. From the data representing the
refractive values measured for the individual over a period of time, the
system
invokes the RECIPY calculator module 180 to compute the rate of refractive
change
value of an individual over a period of time at 220. By annualizing the rate
of change,
the system calculates the "RECIPY" Refractive Error Change In the Previous
Year.
For example, if refractive error data is known for 2 years prior to the
current date and
the change in refraction was -2D, then there would be a RECIPY value of -1D
where
D is diopters. Although typically measured in clinical practice as refractive
error
change, future progression is captured as axial elongation as this parameter
is a
more sensitive measure than refractive error in monitoring progression and is
most
relevant to the development of myopia related changes, such as myopic
retinopathy.
100401 While myopia progression may be characterized by an individual's
refractive error change, according to the present embodiment, myopia
progression is
characterized as the change in axial length of the individual's eye.
Continuing to step
225, Fig. 2, the system 100 runs the change in axial length calculator module
190 for
predicting a change in axial length of the individual's eye. Equation 1) below
represents the predicted change in axial length "AAL" as a function of the
annualized
past rate of refractive change "RECIPY" value, age data received at step 210,
and
axial length data at the time of making the prediction received at 215.
LIAL =f (RECIPY, Age, Axial Length)
100411 specifically,
AAL = [ a (mm/D) x RECIPY (D)] - b (mm/yr) x age (yrs)] +
[c x axial length (mm)] ¨ d (mm) (1)
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where: AAL is the estimated axial elongation of the eye, e.g., over the 12-
month
period after the reference timepoint, and is measured in millimeters, RECIPY
is the
refractive error change in the prior year (or relativized amount where
refraction data
is not specifically available for the prior 12-month period) and is measured
in diopters
D, "age" is the age of the child in years, and "axial length" is the axial
length of the
eye as measured in mm at the reference timepoint. In one embodiment,
coefficient
value a = -0.12051 +/- .05162 (mm/D); coefficient value b = 0.03954 +/-
0.00323
(mm/yr); coefficient value c = 0.036819 +/-0.001098; and value d = 0.35111 +/-
0.025809 (mm).
[0042] It should be understood that, in a further embodiment, equivalent
forms
of equation 1) for predicting a future axial elongation of the eye as a
function of the
prior refractive change, current axial length and age of the patient may be
implemented. Such a prediction of future refractive change may receive a past
axial
elongation measurement as an input parameter. Such a prediction of future
refractive
change may also output a future predicted refractive error change. Further,
the form
of equation 1) may be modified to receive additional input parameters
corresponding
to other potential predictors of refractive error progression including, but
not limited
to: biometric data of the patient or of the patient's eye, such as corneal
radius,
anterior chamber depth, lens thickness, lens power, vitreous chamber depth or
similar, or behavioral aspects of the patient, including but not limited to an
amount of
time engaged in certain activities, including outdoor activity, levels of
close work
activity (e.g., number of reading hours per day or week or month or time spent
on
studying or reading or time spent on digital devices), or information
regarding genetic
make-up of the patient, including but not limited to: a number of myopic
parents or
siblings, the refractive status of the patient's parents or siblings, the
patient's race,
ethnicity, gender, or further parameters including but not limited to a
geographic
location such as country or degree of urbanization, or any other type of
demographic
or environmental variables considered relevant to refractive progression.
[0043] In one embodiment, equation 1) resulted from a model developed to
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predict the future AAL change in refractive progression according to data from
control
groups in clinical studies. In an example study, 100 subjects in the control
groups
have been followed for 2 years and the system obtained cycloplegic
autorefraction,
and axial length data available at baseline, 12 months and 24 months as well
as sex,
race and ethnicity data for the subjects. The first 12-month data was used as
prior
history and the second 12-month data was used as future progression with the
12-
month examination set as the date at which the prediction of progression for
the
second twelve-month period is made (i.e., the 'reference' timepoint). Subjects
included in this dataset were children between 8 and 15 years age (mean SD=
9.8 1.3 years) with baseline best-sphere refraction between -0.75D and -5.00D
and
astigmatism less than or equal to 1.00D. Fifty-one percent of the subjects
were
female and 93% were Asian. Only the right eyes of the subjects were included
in the
dataset for analysis. The mean ( SD) of "RECIPY" of this dataset was -0.64
0.52D in
refraction change (range: -2.25 to +0.50D). Axial elongation during the first
12-month
period was 0.25 0.16mm (range: -0.18 to 0.65mm). At the beginning of the 2nd
year,
the mean SD of spherical equivalent of cycloplegic autorefraction was -3.35
1.26D
(range: -1.37 to -6.87D), and the mean SD of axial length was 24.86 0.87mm
(range: 23.07 to 26.78mm).
[0044] Data available included RECIPY, refractive error and axial length
at the
reference timepoint, sex, ethnicity and axial elongation in the 2nd 12-month
period. A
multivariate analysis was conducted and yielded equation 1) to relate the
variables
and obtain:
AAL = [ -0.12051(mm/D) x RECIPY (D)] - [0.03954 (mm/yr) x age (yrs)]
+ [0.036819 x axial length (mm)] ¨ 0.35111(mm).
[0045] Statistical information on the fits are shown in the Table 1 below
where
F and P represents statistical values that determine a statistical
significance as
derived from conducting an analysis of variance. Based on the low P values, it
is
seen that the RECIPY, Age and Axial Length are significant predictor values.
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. ,
,
Variable F P
RECIPY 19.36 P<0.0001
Age 12.13 P<0.001
Axial Length 5.28 P<0.05
Table 1
100461 In one embodiment, fast progressors may be considered to have
axial
elongation above, for example, 0.20mm. In this case, the equation 1) algorithm
exhibits a sensitivity of 0.87 and specificity of 0.58. In one embodiment, the
mean
progression in those predicted to be fast progressors is 0.301mm/yr by this
criterion
and was twice that of those predicted to be slow progressors (0.146mm/yr). If
a
cutoff value from the algorithm of 0.23mm is used to predict those who will
progress
more than 0.20mm, the sensitivity is 0.79 with specificity of 0.71.
[0047] Table 2 below shows some selected example predictions for axial
elongation in the 2nd year for the given data at the reference timepoint,
i.e., age at
reference time point, axial length of the referent time point, and the
determined
RECIPY value.
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Predicted Axial
Age RECIPY Axial Length
Elongation
Effect of age
7 -0.500 23.5 0.298
8 -0.500 23.5 0.258
9 -0.500 23.5 0.219
12 -0.500 23.5 0.100
Effect of RECIPY
8 -0.250 23.5 0.228
8 -0.500 23.5 0.258
8 -0.750 23.5 0.288
Effect of axial length
8 -0.500 23.5 0.258
8 -0.500 24.5 0.295
8 -0.500 25.5 0.332
Table 2
100481 Returning to FIG. 2, based on the predicted future AAL change in
refractive progression, a specific type of soft lens or orthokeratology
treatment regime
may be recommended. In one embodiment, in FIG. 2 at 230, the system 100 may
determine an optical device such as a soft contact lens having a suitable
refraction
design for use as myopia treatment for the individual given the individual's
predicted
progression of myopia based on the predicted AAL change over the next year. In
one embodiment, the treatment option may include a multi-focal contact lens
having
positive spherical aberration and increasing dioptric power away from the lens
center
that creates an amount of peripheral "blur" to deprive the eye of light in a
manner as
known for inhibiting the eye's growth. In other embodiment, it may be
determined
that a regimen of eye drops or other pharmaceutical treatment administered to
the
individual may be suitable for reducing the progression of myopia; or a
regimen of
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time spent outdoors may be determined to retard or prevent myopia progression.
Any
treatment option available now or in the future that may reduce, retard,
eliminate or
even reverse the progression of myopia in the individual is determined at 230.
At
235, FIG. 2, the system may automatically generate a recommendation for the
clinician via system display interface 158 whether locally connected to the
system or
for communication over a network to a remote computer.
100491 In one embodiment, the display may be a graphical user interface
of the
computer or a smart device (e.g., a tablet computer, smart phone, personal
digital
assistant, wearable digital device, gaming device, TV). In a specific
embodiment, the
display may be synchronized on an Eye Care provider's computer or smart device
and on a user computer or smart device.
Fast Progressor Prediction
[0050] In one embodiment, system 100 may further identify myopes likely
to be
fast progressors. Detecting of such myopes may be useful for targeting
treatment
regimens and in designing myopia control clinical studies. As it has been
showed that
history of fast progression is a factor of similar or better predictive value
than age, a
well-known risk factor, in assessing likelihood of future fast progression,
the algorithm
of equation 1) including historical refractive progression (RECIPY) may be
used for
predicting future fast progression.
10051] In a further example: the system 100 received the Cycloplegic
autorefraction (CAR) data and axial length data, (e.g., obtained by partial
interferometry) obtained over a time period including at baseline, 1 yr and 2
yrs in
100 children aged 8 to 15 years with -0.75 to -5.00D of myopia. A
multivariable
regression analysis was conducted with right eye axial elongation during the
2nd yr
was fit in the multivariable analysis by refractive error change in the
previous year
(RECIPY), age, gender, ethnicity, 1yr axial length and 1yr refractive error.
Axial
elongation was chosen as the dependent variable because of its better
sensitivity in
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identifying progression, but past refractive change was used as a predictive
variable.
[0052] Example p-value analysis results for RECIPY, age, 1-year axial
length
factors are: RECIPY (p<0.0001), age (p<0.001), 1 yr axial length (p<0.05) and
RECIPY*age interaction (p<0.05) indicating that all these factors contributed
significantly in predicting axial elongation between 1 and 2 yrs. Gender,
ethnicity and
1 yr refractive error did not contribute significantly to predicting of axial
elongation.
The model fit accounted for 57% of the variance in axial elongation in the 2nd
yr.
Using a criterion of 0.2mm, the model has a sensitivity of 0.87 and a
specificity of
0.58 in predicting fast progressors. The mean progression in those categorized
as
fast progressors (0.301mm/yr) by this criterion was twice that of those
predicted to be
slow progressors (0.146mm/yr).
[0053] Thus, the computation of AAL according to equation 1) provides a
good
prediction of future axial elongation. This information is useful in guiding
myopia
control treatment and in design of clinical studies.
[0054] Applicant's co-pending United States Patent Application
No.15/007,660,
the whole contents and disclosure of which is incorporated by reference as if
fully set
forth herein, details a system and method for predicting and tracking an
individual's
refractive error progression over time. The system and method described are
applied
to optimally determine a course of treatment for myopia and for an ECP to
evaluate
over time whether the course of treatment applied for the individual has
been/maybe
effective. ECPs, parents, and patients are thus provided with a better
understanding
of the possible long-term benefit of a particular myopia control treatment.
10055] Based on the system, methods, and computer program products, the
present invention may assist an ECP to choose a type of myopia control
treatment
and/or ophthalmic lens for a child based on the computed future axial
elongation of
the eye and a resulting anticipated progression of myopia.
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[0056] The methods described in co-pending United States Patent
Application
No.15/007,660 system may be implemented for ECPs to demonstrate and track the
effectiveness of treatments to slow the progression of myopia and allow
individuals to
understand the long-term benefit of a myopia control treatment. The principles
described in co-pending United States Patent Application No.15/007,660 may be
applied to track myopia control treatments to slow the progression of myopia
based
on the determining of the predicted axial elongation values according to
equation 1).
[0057] Thus, the tracking methods and system to estimate a potential
axial
elongation of an individual's eye over a future predetermined period of time
relative to
a reference population, may be used to: 1) allow ECPs to predict and track
axial
elongation (and hence, refractive) progression as well as demonstrate and
track the
effectiveness of treatments to slow the progression of myopia and/or 2) allow
patients
or parents to understand the long-term benefit of a myopia control treatment.
[0058] While the principles discussed herein are directed to myopia, the
present invention is not so limited and could be applied to other refractive
errors,
such as hyperopia or astigmatism.
[0059] As will be appreciated by one skilled in the art based on this
disclosure,
aspects of the present invention may be embodied as a system, method, or
computer
program product. Accordingly, aspects of the present invention may take the
form of
an entirely hardware embodiment, a processor operating with software
embodiment
(including firmware, resident software, micro-code, etc.) or an embodiment
combining
software and hardware aspects that may all generally be referred to herein as
a
"circuit," "module" or "system." Furthermore, aspects of the present invention
may
take the form of a computer program product embodied in one or more computer
readable medium(s) having computer readable program code embodied thereon.
[0060] Any combination of one or more computer readable medium(s) may be
utilized. The computer readable medium may be a computer readable signal
medium or a computer readable storage medium. A computer readable storage
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medium may be, for example, but not limited to, an electronic, magnetic,
optical,
electromagnetic, infrared, or semiconductor system, apparatus, or device, or
any
suitable combination of the foregoing. More specific examples (a non-
exhaustive list)
of the computer readable storage medium would include the following: an
electrical
connection having one or more wires, a portable computer diskette, a hard
disk, a
random access memory (RAM), a read-only memory (ROM), an erasable
programmable read-only memory (EPROM or Flash memory), an optical fiber, a
portable compact disc read-only memory (CD-ROM), an optical storage device, a
magnetic storage device, or any suitable combination of the foregoing. In the
context
of this disclosure, a computer readable storage medium may be any tangible
medium
that can contain, or store a program for use by or in connection with an
instruction
execution system, apparatus, or device.
[0061] Computer program code for carrying out operations for aspects of
the
present invention may be written in any combination of one or more programming
languages, including an object-oriented programming language such as Java,
Smalltalk, C++, C#, Transact-SQL, XML, PHP or the like and conventional
procedural
programming languages, such as the "C" programming language or similar
programming languages. The program code may execute entirely on the user's
computer, partly on the user's computer, as a stand-alone software package,
partly
on the user's computer and partly on a remote computer or entirely on the
remote
computer or server. In the latter scenario, the remote computer may be
connected to
the user's computer through any type of network, including a local area
network
(LAN) or a wide area network (WAN), or the connection may be made to an
external
computer (for example, through the Internet using an Internet Service
Provider).
[0062] Computer program instructions may be provided to a processor of a
general-purpose computer, special purpose computer, or other programmable data
processing apparatus to produce a machine, such that the instructions, which
execute with the processor of the computer or other programmable data
processing
apparatus, create means for implementing the functions/acts specified.
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[0063] These computer program instructions may also be stored in a
computer
readable medium that can direct a computer, other programmable data processing
apparatus, or other devices to function in a particular manner, such that the
instructions stored in the computer readable medium produce an article of
manufacture including instructions which implement the functions/acts
specified.
[0064] The computer program instructions may also be loaded onto a
computer, other programmable data processing apparatus, or other devices to
cause
a series of operational steps to be performed on the computer, other
programmable
apparatus or other devices to produce a computer implemented process such that
the instructions which execute on the computer or other programmable apparatus
provide processes for implementing the functions/acts specified.
[0065] Referring now to FIG. 3, a representative hardware environment for
practicing at least one embodiment of the invention is depicted. This
schematic
drawing illustrates a hardware configuration of an information
handling/computer
system in accordance with at least one embodiment of the invention. The system
comprises at least one processor or central processing unit (CPU) 10. The CPUs
10
are interconnected with system bus 12 to various devices such as a random
access
memory (RAM) 14, read-only memory (ROM) 16, and an input/output (I/O) adapter
18. The I/O adapter 18 can connect to peripheral devices, such as disk units
11 and
tape drives 13, or other program storage devices that are readable by the
system.
The system can read the inventive instructions on the program storage devices
and
follow these instructions to execute the methodology of at least one
embodiment of
the invention. The system further includes a user interface adapter 19 that
connects a
keyboard 15, mouse 17, speaker 24, microphone 22, and/or other user interface
devices such as a touch screen device (not shown) to the bus 12 to gather user
input. Additionally, a communication adapter 20 connects the bus 12 to a data
processing network 25, and a display adapter 21 connects the bus 12 to a
display
device 23 which may be embodied as an output device such as a monitor,
printer, or
transmitter, for example.
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[0066] The terminology used herein is for the purpose of describing
particular
embodiments only and is not intended to be limiting of the invention. As used
herein,
the singular forms "a", "an" and "the" are intended to include the plural
forms as well,
unless the context clearly indicates otherwise. It will be further understood
that the
root terms "include" and/or "have", when used in this specification, specify
the
presence of stated features, integers, steps, operations, elements, and/or
components, but do not preclude the presence or addition of one or more other
features, integers, steps, operations, elements, components, and/or groups
thereof.
[0067] As used herein, "in communication" includes physical and wireless
connections that are indirect through one or more additional components (or
over a
network) or directly between the two components described as being in
communication.
[0068] Although shown and described is what is believed to be the most
practical and preferred embodiments, it is apparent that departures from
specific
designs and methods described and shown will suggest themselves to those
skilled
in the art and may be used without departing from the spirit and scope of the
invention. The present invention is not restricted to the particular
constructions
described and illustrated, but should be constructed to cohere with all
modifications
that may fall within the scope of the appended claims.
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