High Myopia cures by rest methods

Discussion in 'Optometry Archives' started by g.gatti, Jul 1, 2005.

  1. g.gatti

    g.gatti Guest

    Just wanted to let you know that I am not dead or handcuffed in prison
    but was working on several interesting projects and could not post as
    usual.

    Now I have met another friend with -17 D of myopic prescription.

    Although he had abandoned glasses three months earlier and started
    self-treatment according to Dr. Bates books, when I first met him and
    the cellular phone rang, he neared it at about 7 cm from his eyes to
    see who was calling.

    I resented about this and we started a few games with the Snellen
    chart.

    The day after, after having worked for several hours continuously with
    such a chart, the boy went home in Naples after having read 7/10 at 10
    feet, under electric light.

    Of course the vision was not continuous, but the feat was great for
    him.

    Then I have to report that my friend who is under self-treatment curing
    her -23 D myopic prescription has had her first TRUE flash of PERFECT
    SIGHT which lasted more than three seconds.

    She was able to see license plates numbers at 15 meters, but since she
    could see neatly the embossing of the letters, her vision was much more
    than that.

    How you learned men explain this without having to allow the eye to
    return back in its normal shape by means of external muscles, I do not
    know.

    Intersting article for you:

    I thought you might be interested in this article from eMedicine. You
    may either click on the following link or copy and paste it into your
    browser.http://www.emedicine.com/oph/topic723.htmeMedicine is the
    leading provider of clinical medical information for medical
    professionals and consumers. To explore eMedicine today visit
    http://www.emedicine.com
     
    g.gatti, Jul 1, 2005
    #1
    1. Advertisements

  2. g.gatti

    Neil Brooks Guest

    Oh, God. It's back.

    Same deal. I'm out. Though it may pain me, and test my resolve, I
    shan't engage this troll.

    Please join me in this effort. Please allow Rishi's (and Otis's)
    words to echo in the cosmos, unanswered. Eventually, they /will/ go
    away.

    If /I/ can do it, . . . .

    Neil
     
    Neil Brooks, Jul 1, 2005
    #2
    1. Advertisements

  3. g.gatti

    otisbrown Guest

    Dear Rishi,

    Subject: Bates bucked the "system".

    Good to hear you are still alive and
    kicking.

    The ODs on this site have determined
    that they will make no comment on:

    1. The dynamic behavior of the
    natural eye.

    2. The results of any and
    all experiments that prove
    that the natural eye "adapts" to
    a minus lens.

    3. Any statement by anyone,
    "Bates supporter" or
    Raphaelson supporter
    who proposes that a negative
    refractive state can be prevented
    by ANY METHOD.

    Medicine tends to "work" by
    default. You "complain" about
    something -- and get a resultant
    quick-fix.

    I truly understand the "power"
    of this method -- and the difficulty
    of "bucking" this system -- but
    sometimes it is worth the effort.

    In any event -- post what you
    like, and enjoy the various responses.

    Best,

    Otis
     
    otisbrown, Jul 1, 2005
    #3
  4. Wow it's the legendary Rishi. I remember reading some of your stuff.
    You're insane. But I am too. Your link doesn't work, idiot. Anyways,
    welcome back. It's a pleasure to meet you.
     
    CHINESEMALE(age16), Jul 2, 2005
    #4
  5. g.gatti

    otisbrown Guest

    Dear Rishi and fellow "objectors",

    There is a strong scientific base for "objecting" to the
    traditional minus lens -- put is place 400 years ago
    because it works "instantly".

    I am certainly respectful of that fact.

    But eqully, there is a small group of people, scientists,
    optometrists, ophthalmologists, and laymen (and Bates)
    who "object".

    In this "objection" we should respect each other
    and the true difficulties of prevention.

    Those difficulties suggest that we should share information,
    and work towards a better "solution" -- and not
    fight with each other as we attempt to accomplish
    this preventive work.

    Best,

    Otis
     
    otisbrown, Jul 2, 2005
    #5
  6. g.gatti

    g.gatti Guest

    But why do you bother?

    People is getting cures.

    Now another friend with CONICAL CORNEA uncorrected even by 6 dioptres
    of convex lens has having flashes of NORMAL SIGHT at three meters with
    that eye, reading the 10 line at 10 feet on the black chart. The other
    eye has 20/10 vision.

    This guy is very much intelligent, and after a little bit of
    awkwardness at beginning of treatment, he started seriously to exercise
    his own imagination and got great progress.

    DO you know what is a conical cornea?

    To the other super-idiot from China (a great country with many young
    children, it is normal that some of them are idiots) I must tell that
    the link works very well.

    Here is the abstract

    Presbyopia: Cause and Treatment
    Last Updated: February 21, 2005
    Rate this Article
    Email to a Colleague
    Synonyms and related keywords: vision loss, visual deficit

    AUTHOR INFORMATION Section 1 of 10 Click here to go to the next
    section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    Author: Ronald Schachar, MD, PhD, President and CEO, Presby Corporation

    Ronald Schachar, MD, PhD, is a member of the following medical
    societies: American Academy of Ophthalmology, American Association for
    the Advancement of Science, American Medical Association, American
    Society of Contemporary Ophthalmology, Phi Beta Kappa, Sigma Xi, and
    Texas Medical Association

    Editor(s): Stephen D Plager, MD, FACS, Chief, Department of
    Ophthalmology, Dominican Hospital; Assistant Clinical Professor,
    Department of Ophthalmology, Stanford University Hospital; Donald S
    Fong, MD, MPH, Assistant Clinical Professor of Ophthalmology, Director,
    Clinical Trials Research, Department of Ophthalmology, Southern
    California Permanente Medical Group; J James Rowsey, MD, Consulting
    Staff, Department of Corneal and Refractive Surgery, St Luke's
    Hospital; Lance L Brown, OD, MD, Ophthalmologist, Regional Eye Center,
    Affiliated With Freeman Hospital and St John's Hospital, Joplin,
    Missouri; and Hampton Roy, Sr, MD, Clinical Associate Professor,
    Department of Ophthalmology, University of Arkansas for Medical
    Sciences

    Disclosure
    INTRODUCTION Section 2 of 10 Click here to go to the previous
    section in this topic Click here to go to the top of this page Click
    here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    The scleral expansion band procedure for the surgical reversal of
    presbyopia (SRP) is a new technique. The scleral expansion band
    procedure has been developed for SRP. The effects of the scleral
    expansion band are based on a recently developed theory by Schachar
    that states that the crystalline lens is under increased equatorial
    zonular tension during accommodation. An understanding of demonstrable
    clinical effects of the scleral expansion band procedure, based upon
    Schachar's theory, requires a revision of historically held views
    concerning the mechanism of accommodation.
    HELMHOLTZ'S THEORY OF ACCOMMODATION Section 3 of 10 Click here to
    go to the previous section in this topic Click here to go to the top of
    this page Click here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    According to Helmholtz, during accommodation, when the optical power is
    greatest, the zonules are relaxed and the crystalline lens can shift.
    The lens would not be stable while reading or examining close objects.
    The instability of the crystalline lens during near vision did not seem
    physically correct. When viewing through an optical system, the higher
    the magnification, the more stable the system needs to be.

    According to Helmholtz's hypothesis, since the equatorial diameter
    increases with age (ie, since the crystalline lens equator is getting
    closer to the ciliary muscle), the zonules should relax. As one ages,
    the power of the crystalline lens should increase while viewing distant
    objects in the accommodated state. One should become more myopic and
    the crystalline lens should become unstable, but in fact, one becomes
    slightly hyperopic and the crystalline lens remains stable. Helmholtz's
    theory also is not consistent with the decrease in spherical aberration
    that occurs during accommodation.

    Helmholtz attributes the universal linear decrease in the amplitude of
    accommodation with age to hardening of the crystalline lens. No tissue
    in the body uniformly hardens in a linear fashion with age. During
    cataract extraction, it commonly is observed that crystalline lenses
    have different degrees of hardness and no uniform loss of water content
    of the crystalline lens with age has been demonstrated. Even in those
    cataracts that have a hard nucleus, the cortex is soft.
    SCHACHAR'S THEORY OF ACCOMMODATION Section 4 of 10 Click here to
    go to the previous section in this topic Click here to go to the top of
    this page Click here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    An outward equatorial displacement of the crystalline lens produces
    central steepening. This counterintuitive phenomenon is demonstrated
    readily by pulling on the equator of a biconvex air-filled Mylar
    balloon and observing that the reflections from the center of the
    balloon become smaller, or minify, (see Picture 2), and the reflections
    from its periphery enlarge (see Picture 3).

    The equatorial displacement of the crystalline lens occurs as a result
    of increased tension on the equatorial zonules (see Picture 4),
    produced by contraction of the anterior radial muscle fibers of the
    ciliary muscle (see Picture 5, Picture 6). Since an active force is
    involved in accommodation, the amount of force that the ciliary muscle
    can apply is dependent on how much the ciliary muscle is stretched.

    The crystalline lens is of ectodermal origin and continues to grow
    throughout life. Except for the progressive myope, the dimensions of
    the scleral shell do not change significantly after 13 years. The
    distance between the ciliary muscle and the equator of the lens
    decreases throughout life. Therefore, the effective force that the
    ciliary muscle can apply to the lens equator is reduced in a linear
    fashion with age. The amplitude of accommodation decreases linearly
    with age resulting in presbyopia and is a consequence of normal lens
    growth.

    Quick Find
    Author Information
    Introduction
    Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation
    Augmentation Of Accommodative Function
    Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation
    Methods For Treating Presbyopia
    Pictures
    Bibliography

    Click for related images.

    Continuing Education
    CME available for this topic. Click here to take this CME.

    Patient Education
    Click here for patient education.



    AUGMENTATION OF ACCOMMODATIVE FUNCTION Section 5 of 10 Click here
    to go to the previous section in this topic Click here to go to the top
    of this page Click here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    Any procedure that increases the distance between the lens equator and
    the ciliary muscle should reverse presbyopia. In the mid 1980s, scleral
    expansion was performed based on these concepts by making multiple
    incisions in the sclera over the ciliary muscle. The scleral incisions
    produced accommodative amplitude increases of only +1.25 diopters (D)
    in young presbyopes and the effect regressed. Fukuska independently
    confirmed these observations and predictions.

    In 1992, the first scleral expansion band procedure was performed using
    a plastic polymethyl methacrylate (PMMA) circular band sutured to the
    sclera (see Picture 6). The results were dramatic. Presbyopic patients
    had as much as 10 D of accommodation. Since that time, the scleral
    expansion band procedure has been modified and improved, so that now a
    separate PMMA segment is placed in each of the 4 oblique quadrants of
    the eye (see Picture 8, Picture 9).

    To date, the worldwide experience with the scleral expansion band
    procedure for the SRP involves more than 500 eyes with a range of
    accommodative recovery of 1.3-7 D with a mean of 3.25 D. In general,
    the response has been favorable with no change in distance refraction,
    best-corrected visual acuity, or axial length. Common adverse effects
    that resolve in 6-8 weeks include subconjunctival hemorrhage, transient
    astigmatism, fluctuating near vision, and dry eyes.
    COMPARISON OF THE HELMHOLTZ THEORY AND THE SCHACHAR THEORY Section
    6 of 10 Click here to go to the previous section in this topic Click
    here to go to the top of this page Click here to go to the next section
    in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    The Schachar theory of accommodation has met considerable reaction and
    discussion, especially from those subscribing to the Helmholtz theory.
    Many past experiments have been published that are in disagreement with
    Schachar's conclusions that the crystalline lens diameter increases
    during accommodation. A careful examination of these experiments
    reveals that a systematic error exists. Movement occurs between the
    imaging device and the eye. Measurement of the thickness of the cornea
    in the accommodated and unaccommodated states of these experiments
    reveals a change in corneal thickness. Since corneal curvature and
    corneal thickness do not change during accommodation, these experiments
    are flawed and cannot be used to reveal the mechanism of accommodation.

    The recent experiments by Glasser and Kaufman are similarly flawed.
    Although they placed sutures in the cornea as a reference point,
    neither the sutures, nor the corneal Purkinje images, subtract out of
    the overlain accommodated and unaccommodated images, demonstrating that
    eye movement occurred between the imaging device and the eye. They
    stated that the small amount of eye movement observed in their
    experiments cannot account for the changes in the crystalline lens size
    and configuration during Edinger Westphal or pharmacologic stimulation;
    however, they offer no controls to prove that this statement is true.

    Interestingly, when they fixated the lateral rectus, so that eye
    movement was reduced, they observed that the crystalline lens equator
    moved toward the sclera, with anterior and posterior zonular
    relaxation. They state that the movement of the crystalline lens
    equator toward the temporal sclera is caused by lateral translation of
    the crystalline lens. This is mechanically impossible. Since the
    crystalline lens is denser than water and vitreous, when the anterior
    and posterior zonules are relaxed, the crystalline lens equator can
    only move toward the temporal sclera by an active generated force (eg,
    by the pull of the equatorial zonules).

    The importance of eye movement relative to the imaging device is
    exemplified by MRI studies performed on accommodating patients by
    Strenk et al. An MRI image of the patient's eye during accommodation
    revealed that the eye is turned nasally and that a change in the
    configuration of the orbital bones occurred. Therefore, both the head
    and eye moved during accommodation.

    Measurement of the transverse diameter of the globe, the corneal
    diameter, and the equatorial diameter of the crystalline lens in the
    unaccommodated and accommodated states, demonstrate that all these
    measurements decrease during accommodation. This means that the image
    plane of the eye in the unaccommodated and accommodated states was not
    the same. Their observations are due to artifact, and any conclusion
    that they make concerning the mechanism of accommodation from this MRI
    study is not valid. For example, they conclude that the equatorial
    diameter of the crystalline lens does not increase with age. Their
    conclusion is contrary to actual histologic measurements.

    Linear and nonlinear finite element mathematical analyses have been
    performed on the human crystalline lens. Nonlinear finite element
    analysis is used routinely to reliably predict reality. The
    mathematical analysis demonstrates that only equatorial stretching of
    the equator of the crystalline lens by the equatorial zonules can
    produce the clinically observed increase in central optical power
    accompanied by a decrease in spherical aberration.

    Scanning electron microscopy has shown the following 3 types of
    zonules: anterior, posterior, and equatorial. The equatorial zonules
    act similar to a skeletal muscle tendon and are the components that
    transduce the force of the ciliary muscle to change the focal power of
    the crystalline lens. The anterior and posterior zonules are tense
    during distance vision and relax during accommodation. The anterior and
    posterior zonules act similar to the ligaments of skeletal joints and
    are stabilizing components, predominately for distance vision.

    Since only the anterior and posterior zonules can be visualized with a
    slit lamp in vivo during accommodation, it is understandable how
    incorrect deductions have been made. Investigators have demonstrated
    that the crystalline lens is stable and gravity does not affect the
    amplitude of accommodation. The equatorial zonules have a separate and
    distinct insertion into the ciliary body. The crystalline lens remains
    stable because the anterior zonules maintain the same position on the
    anterior crystalline lens surface even though the crystalline lens
    equator is enlarging with increasing age.

    In vivo measurements of the position of the crystalline lens equator of
    young human research subjects during pharmacologically controlled
    accommodation using high-frequency, high-resolution anterior segment
    ultrasound revealed that the crystalline lens moves toward the sclera
    during accommodation. The mean movement was 6.8±1 mm/D. This amount of
    equatorial movement during accommodation was consistent with the
    prediction of the nonlinear finite element mode and demonstrated that
    accommodation is a small displacement phenomenon (ie, <5% change occurs
    in the equatorial diameter of the crystalline lens during
    accommodation).

    The small amount of equatorial crystalline lens movement explains the
    problems and the systemic errors that have occurred during previous
    experiments that try to determine the position of the crystalline lens
    equator during accommodation. Eye movements are much larger than the
    movement of the crystalline lens equator; therefore, proper controls
    are essential to interpret any measurements.

    Table 1. Comparison of the Helmholtz Theory and the Schachar Theory
    Test Helmholtz Schachar Observation
    Small displacement equatorial stretching of the biconvex deformable
    lens Decrease in central optical power Large increases in central
    optical power Large increases in central optical power
    Effect of gravity on the amplitude of accommodation Yes No No
    Effect of accommodation on spherical aberration Increase Decrease
    Decrease
    Change in refraction following presbyopia Myopic Hyperopic Hyperopic
    Anterior disinsertion of the ciliary muscle Myopic Hyperopic
    Hyperopic
    Change in the circular muscle fibers following presbyopia Atrophy
    Hypertrophy Hypertrophy
    Change in the anterior radial muscle fibers following presbyopia
    Little or no effect Atrophy

    Atrophy
    Theory has widespread and new applications No Yes

    1. Profile of the ocean tides
    2. Effect of a magnetic field on a magnetic fluid
    3. The shape of normal spiral galaxies
    The effect of tight 12-o'clock position cataract wound sutures on the
    central curvature of the cornea The cornea flattens in the vertical
    meridian (against the rule astigmatism) The cornea steepens in the
    vertical meridian (with the rule astigmatism) The cornea steepens in
    the vertical meridian (with the rule astigmatism)

    For the first time, the theory has predicted methods to surgically
    reverse presbyopia, to produce a single element variable focus lens
    that can have rapid large optical power changes from small equatorial
    displacement, and to treat and to prevent ocular hypertension and
    primary open-angle glaucoma. The continued challenge will be to perform
    properly controlled experiments and to see how this theory will provide
    new tools and better methods for improving the visual performance of
    patients.
    HISTORICAL PERSPECTIVE OF THE THEORIES OF THE MECHANISM OF
    ACCOMMODATION Section 7 of 10 Click here to go to the previous
    section in this topic Click here to go to the top of this page Click
    here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    The healthy, young human (<40 y) or young primate eye can rapidly focus
    on near and distant objects (ie, it can change focus or accommodate).
    The mechanism by which the eye can accomplish this amazing task has
    been speculated upon for centuries. Initially, it was suggested that
    the eye was divinely created; therefore, it did not follow known
    physical laws of optics.

    In 1619, Scheiner, a Jesuit priest, proved that accommodation occurred
    as a result of a change in the optical power of the eye and that the
    eye obeyed the laws of optics. His experiment easily is duplicated and
    consists of making 2 vertical pinholes in a card, which are separated
    by less than the diameter of the pupil of the eye. The observer looks
    through both holes simultaneously and focuses on a needle held
    perpendicular to the plane of the holes. When focusing on the needle,
    it will appear single; however, if the observer focuses on a more
    distant or near object, the needle will appear doubled. This simple
    elegant experiment demonstrates that the eye functions as an optical
    system.

    The explanation of Scheiner's experiment is demonstrated in Picture 10.
    Consider a point source of light as the object. A convex lens converges
    the rays of light to a point. By placing a card containing 2 holes
    between the point source and the convex lens, only 2 rays are brought
    to a focus. If the power of the convex lens is changed, then the 2 rays
    are brought to a focus at a different distance. The point source
    appears doubled at all other distances. If the card has 3 or 4 holes,
    the point source will triple or quadruple.

    Some of the most famous philosophers and scientists were interested in
    how the eye accommodates. In 1611, Kepler and others thought the
    crystalline lens moved forward and backward. In 1677, Descartes
    suggested that the shape of the crystalline lens changed. In 1742, Lobe
    postulated that the shape of the cornea changed. Sturm and Listing
    believed that the eye elongated.

    In 1801, Thomas Young, using ingenious experiments, provided evidence
    that accommodation occurs as a result of changes in shape of the
    crystalline lens. He had very prominent eyes. Without anesthesia (which
    had not been discovered yet) he placed a caliper, that had rings
    attached to each side, around his eye. With his eye rotated nasally, he
    placed 1 ring on his cornea and the other ring over his macula. He
    could see a circular entopic ring induced by the ring on his macula. As
    he changed his point of focus, the entopic ring did not change size.
    This proved that the eye does not elongate during accommodation.

    Next, he calculated the amount the cornea would have to move forward to
    account for his accommodative amplitude. Using candles and a front
    surface mirror engraved with a scale, he did not observe any corneal
    movement as he changed his point of focus. He further proved that the
    radius of curvature of the cornea does not play a role in
    accommodation. He attached a convex lens possessing the optical power
    of the cornea to the bottom of an eyecup. He filled the eyecup with
    saline and placed it over his cornea (the forerunner of contact
    lenses). The saline in contact with the cornea eliminated the
    refractive power of the cornea; yet, he was still able to fully
    accommodate.

    Young demonstrated that accommodation did not occur in aphakes. He
    realized that accommodation had to result from a change in position or
    shape of the crystalline lens. He was convinced that accommodation
    could not occur because of forward or backward movement of the
    crystalline lens. He calculated that the crystalline lens would have to
    move 10 mm to account for his amplitude of accommodation. This would be
    impossible.

    Young observed that spherical aberration decreased during
    accommodation. He concluded that accommodation occurs as a result of a
    change in shape of the crystalline lens. Since the ciliary body had not
    been discovered yet, he postulated that the change in shape of the
    crystalline lens is induced by a muscular mechanism within the
    crystalline lens.

    In 1823, Purkinje noted the reflected images of a candle from the
    anterior and posterior crystalline lens surfaces. In 1849, Langenbeck
    was able to observe in a patient that the Purkinje image from the
    anterior surface of the crystalline lens became smaller during
    accommodation by using a candle and a magnifying glass. He correctly
    concluded that the anterior surface of the crystalline lens becomes
    more convex during accommodation. He proposed that the ciliary muscle,
    which had been discovered independently by Bruecke and Bowman in 1847,
    squeezes the crystalline lens.

    In 1851, Cramer followed up on Langenbeck's observation and improved on
    it by making a device that incorporated a telescope to allow accurate
    observations of the Purkinje images during accommodation. He observed
    that the anterior surface of the crystalline lens became more convex,
    but the posterior surface did not change shape.

    In 1855, Helmholtz improved on the Cramer device by placing crossed
    glass plates between the patient's eye and the telescope, so that the
    Purkinje images were doubled and could be measured more accurately. In
    addition to observing that the anterior and posterior surfaces of the
    crystalline lens became more convex, he noted that the lens became
    thicker during accommodation. He hypothesized that the ciliary muscle
    relaxes during accommodation allowing the lens to become more spherical
    under the influence of its own elasticity. According to his hypothesis,
    the equatorial diameter of the lens should decrease as it becomes more
    spherical during accommodation. He postulated that presbyopia, the loss
    of accommodation with age, occurred as a result of lens sclerosis (ie,
    loss of elasticity of the lens with age).

    In 1864, Donders studied the change of the amplitude of accommodation
    with age. He found that the amplitude of accommodation declined in a
    linear fashion with age. This decline occurs universally and
    predictably. If patients are corrected properly for distance vision,
    their age can be determined within 1.5 years by measuring their
    amplitude of accommodation. Donders also observed that patients become
    slightly hyperopic when they become presbyopic.

    In 1901, Tscherning examined the curvature changes of the anterior
    crystalline lens surface by observing the changes in the Purkinje
    images when 4 lights are used as objects. He placed the lights so that
    2 formed reflected images from the central anterior surface and 2
    formed reflected images from the peripheral anterior surface of the
    crystalline lens. He observed that the central images moved closer
    together during accommodation, while the peripheral images moved
    further apart. He concluded that the crystalline lens was becoming more
    convex centrally but was becoming flatter in the periphery during
    accommodation. This was consistent with Young's observation that the
    spherical aberration of the eye decreases during accommodation.

    Helmholtz's theory did not explain the peripheral flattening of the
    crystalline lens without additional assumptions. For example, the iris
    constricts during accommodation and it was imputed to produce the
    peripheral flattening of the crystalline lens. However, von Graefe had
    demonstrated accommodation in a patient with a total iridectomy.

    Tscherning postulated that during accommodation the ciliary muscle
    exerted tension on the crystalline lens, pressing the crystalline lens
    against the anterior vitreous. The resistance of the vitreous
    transmitted sufficient force to effect central bulging of the anterior
    surface of the crystalline lens. His theory predicts that the central
    thickness should decrease during accommodation. He did not accept
    Helmholtz's measurements of increasing crystalline lens thickness with
    accommodation. Tscherning thought that presbyopia was the result of
    enlargement of the crystalline lens nucleus. All subsequent theories
    Gullstrand (1911), Fincham (1937) used Helmholtz's hypothesis that the
    zonules are relaxed during accommodation. Helmholtz's hypothesis and
    subsequent modifications attribute presbyopia to sclerosis of the
    crystalline lens stroma or capsule, atrophy of the ciliary muscle, or
    stiffening of the ciliary muscle attachments.

    Based on these theories for the mechanism of accommodation, the
    amplitude of accommodation could be increased only by softening the
    lens stroma and/or capsule, rejuvenating the ciliary muscle by somehow
    reversing ciliary muscle atrophy, or reversing ciliary body fibrosis.
    Since none of these methods are clinically possible there has been no
    surgical therapy for increasing the amplitude of accommodation and
    reversing the symptoms of presbyopia.
    METHODS FOR TREATING PRESBYOPIA Section 8 of 10 Click here to go
    to the previous section in this topic Click here to go to the top of
    this page Click here to go to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    Presbyopia initially was treated with near vision optical aids using
    magnifying lenses, reading glasses, and monocles. Patients were
    constantly removing reading glasses and losing them because the reading
    glasses interfere with vision at all other distances. Benjamin Franklin
    fused the distance lens with the near reading lens to give us bifocals
    that were later modified to trifocals. The problem with these reading
    aids is that they only allow sharp near vision at a given distance and
    the near visual field is limited by the lens. Patients must learn to
    rotate their eyes downward when reading with bifocals instead of
    rotating their head. It usually takes 2-3 weeks for patients to get
    used to wearing bifocals. Trifocals can even be more of a problem for
    many patients.

    To avoid the problems of bifocals and trifocals, bifocal contact lenses
    have been developed. The bifocal contact lenses generally have been
    unsuccessful because the distance and near powers of the contact lens
    must be crowded into an area that can barely cover the pupil. The
    patient must learn how to shift the contact lens and to ignore the
    distant or near image according to the visual task.

    Multifocal glasses and multifocal contact lenses also are generally not
    satisfactory. Multifocal lenses produce multiple images at various
    focal points. Light reflected or emitted by an object must be dispersed
    by the multifocal lens over all the focal points. Therefore, the
    intensity at any given focal point will be reduced and the contrast
    sensitivity diminished. To avoid prismatic effects, the visual field of
    a multifocal lens is reduced. In addition, the patient must learn to
    select the appropriate image.

    The problems with bifocal and multifocal contact lenses forecast the
    problems that have, and will continue to occur, with attempts at making
    a bifocal or multifocal cornea using LASIK, or using intracorneal
    lenses, or phakic intraocular lenses.

    Monovision as a treatment for presbyopia generally is accepted by fewer
    than 30% of the population. The loss of stereopsis and learning to
    ignore a blurry image from one half of the binocular visual field
    easily accounts for the patient's distress with monovision.

    Summary

    Treatments for presbyopia have not been very good because the
    physiological mechanism of the crystalline lens has not been restored.
    The Schachar theory of accommodation states the following:

    1. Increased equatorial zonular tension occurs during accommodation.

    2. Presbyopia is due to a decrease in the effective working distance of
    the ciliary muscle as a result of normal crystalline lens growth.

    Based on this theory the accommodative amplitude of presbyopes can be
    increased.

    Any technique that increases the effective working distance of the
    ciliary muscle, the distance between the ciliary muscle and the
    crystalline lens equator, increases the amplitude of accommodation
    physiologically.
    Table 2. Comparison of Methods for Treating Presbyopia



    Focus at Multiple Near Distances


    Full Clear Visual Field


    Reversible


    Large Range of Correction


    Effect Regresses


    Normal Stereopsis


    Negative Cosmetic Implications


    Physiological


    Involves a Surgical Technique


    Halos at Night


    Potential for Serious Complications

    Reading glasses


    No


    No


    Yes


    Yes


    N/A


    Yes


    Yes


    No


    No


    No


    None

    Bifocals glasses


    No


    No


    Yes


    Yes


    N/A


    Yes


    Yes


    No


    No


    No


    None

    Trifocals glasses


    No


    No


    Yes


    Yes


    N/A


    Yes


    Yes


    No


    No


    No


    None

    Monovision


    No


    No


    Yes


    Yes


    N/A


    No


    No


    No


    No


    No


    None

    Multifocals glasses


    Yes


    No


    Yes


    Yes


    N/A


    Yes


    No


    No


    No


    No


    None

    Bifocal contacts


    No


    No


    Yes


    Yes


    N/A


    Yes


    No


    No


    No


    No


    Minimal

    Multifocal contacts


    Yes


    No


    Yes


    Yes


    N/A


    Yes


    No


    No


    No


    No


    Minimal

    Intracorneal lenses


    No


    No


    Yes


    Yes


    No


    Yes


    No


    No


    Yes


    No


    Significant

    Intracorneal multifocal lenses


    Yes


    No


    Yes


    Yes


    No


    Yes


    No


    No


    Yes


    Yes


    Significant

    Phakic intraocular lenses


    No


    No


    Yes


    Yes


    No


    Yes


    No


    No


    Yes


    Yes


    Significant

    Phakic multifocal intraocular Lenses


    Yes


    No


    Yes


    Yes


    No


    Yes


    No


    No


    Yes


    Yes


    Significant

    LASIK produced bifocal cornea


    No


    No


    No


    Yes


    No


    Yes


    No


    No


    Yes


    Yes


    Significant

    LASIK produced multifocal cornea


    Yes


    No


    No


    Yes


    No


    Yes


    No


    No


    Yes


    Yes


    Significant

    Scleral incisions


    Yes


    Yes


    Yes


    No


    Yes


    Yes


    No


    Yes


    Yes


    No


    Minimal

    Scleral expansion band


    Yes


    Yes


    Yes


    Yes


    No


    Yes


    No


    Yes


    Yes


    No


    Minimal
    PICTURES Section 9 of 10 Click here to go to the previous section
    in this topic Click here to go to the top of this page Click here to go
    to the next section in this topic
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    Caption: Picture 1. Keratoconjunctivitis, Atopic
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 2. Reflection in the center of the balloon
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 3. Reflection in the periphery of the balloon
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 4. In the unaccommodated state, all the zonules are
    under tension (a). According to the Schachar theory, in the
    accommodated state, the equatorial zonules are under increased tension,
    and the anterior and posterior zonules are relaxed (b).
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 5. Schema of the configuration of the eye in the
    unaccommodated state.
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 6. Schema of the configuration of the ciliary body in
    the accommodated state according to the Schachar theory.
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 7. Polymethyl methacrylate band
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 8. Incisions for placement of the polymethyl
    methacrylate band
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 9. Placement of the polymethyl methacrylate band
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Image
    Caption: Picture 10. Scheiner's experiment
    Click to see larger picture Click to see detailView Full Size Image
    Click to ZoomeMedicine Zoom View (Interactive!)
    Picture Type: Graph
    BIBLIOGRAPHY Section 10 of 10 Click here to go to the previous
    section in this topic Click here to go to the top of this page
    Author Information Introduction Helmholtz's Theory Of Accommodation
    Schachar's Theory Of Accommodation Augmentation Of Accommodative
    Function Comparison Of The Helmholtz Theory And The Schachar Theory
    Historical Perspective Of The Theories Of The Mechanism Of
    Accommodation Methods For Treating Presbyopia Pictures Bibliography

    * Atchison DA: Accommodation and presbyopia. Ophthalmic Physiol Opt
    1995 Jul; 15(4): 255-72[Medline].
    * Bowman: Lectures on the Parts concerned in the Operations of the
    Eye. London: 1849:62.
    * Brown N: The shape of the lens equator. Exp Eye Res 1974 Dec;
    19(6): 571-6[Medline].
    * Brucke: Arch Anat Physiol wiss Med. 1846:370.
    * Coulombre JL, Coulombre AJ: Lens development. IV. Size, shape,
    and orientation. Invest Ophthalmol 1969 Jun; 8(3): 251-7[Medline].
    * Cramer N: Lancet. Vol 1. 1851:529.
    * Descartes R: Traite de l'homme. Paris: 1677.
    * Donders FC: Accommodation and refraction of the eye. The New
    Society. London: 1864:204-215.
    * Duke-Elder S, Waybar KC: Anatomy of the visual system. In:
    Duke-Elder, ed. System of Ophthalmology. Vol 2. London: Henry Kimpton;
    1962:80-1.
    * Farnsworth PN, Shyne SE: Anterior zonular shifts with age. Exp
    Eye Res 1979 Mar; 28(3): 291-7[Medline].
    * Fincham EF: Mechanism of accommodation. Br J Ophthalmol 1937; 8:
    5-80.
    * Fincham EF: The mechanism of accommodation. Br J Ophthalmol
    [suppl] 1937; 8: 1-80.
    * Fukasaku H: Silicone expansion plug implant surgery for
    presbyopia. In: Am Soc of Cataract Refractive Surg Symposium. Boston,
    Ma: 2000.
    * Fukasaku H: Surgical Correction of Presbyopia. ASCRS Meeting
    Seattle, WA; April 1999.
    * Glasser A, Kaufman PL: The mechanism of accommodation in
    primates. Ophthalmology 1999 May; 106(5): 863-72[Medline].
    * Glasser A, Kaufman PL: Letter to the editor. Ophthalmology 2000;
    107: 626.
    * Gordon AR, Siegman MJ: Mechanical properties of smooth muscle. I.
    Length-tension and force- velocity relations. Am J Physiol 1971 Nov;
    221(5): 1243-9[Medline].
    * Gullstrand A: Einfurhrung in d. Methoden d. Dioptrik d. Auges d.
    Menschen. Leipzig 1911.
    * Ivanoff A: On the influence of accommodation on spherical
    aberration in the human eye: an attempt to interpret night myopia. J
    Opt Soc Am 1947; 37: 730-1.
    * Kepler: Dioprice. Augsburg: 1611.
    * Kleinman NJ, Worgul BV: Lens. In: Tasman W, ed. Duane's
    Foundations of Clinical Ophthalmology. Vol 1. Philadelphia: 1994.
    * Koomen M, Tousey R, Scolnik R: The spherical aberration of the
    eye. J Opt Soc Am 1949; 39: 370-6.
    * Langenbeck K: Opthal. Gottingen 1849.
    * Levy NS: The mechanism of accommodation in primates.
    Ophthalmology 2000 Apr; 107(4): 625-6[Medline].
    * Levy NS: Letter to the editor. Comparing MRI's with Movement
    Artifact. In: Invest Ophthalmol Vis Sci. 2000; Available at
    http://www.iovs.org[Full Text].
    * Lim SJ, Kang SJ, Kim HB: Analysis of zonular-free zone and lens
    size in relation to axial length of eye with age. J Cataract Refract
    Surg 1998 Mar; 24(3): 390-6[Medline].
    * Listing: Wagner's Handworterbuch d. Physiiologie. Braunschweig
    1853; 4: 498.
    * Lobe: Dissertatio de ocula humano. Vol 119. 1742.
    * Marshall J, Beaconsfield M, Rothery S: The anatomy and
    development of the human lens and zonules. Trans Ophthalmol Soc U K
    1982; 102 Pt 3: 423-40[Medline].
    * Neider MW, Crawford K, Kaufman PL: In vivo videography of the
    rhesus monkey accommodative apparatus. Age- related loss of ciliary
    muscle response to central stimulation. Arch Ophthalmol 1990 Jan;
    108(1): 69-74[Medline].
    * Purkinge: Beobachtungen u. Versuche z. Physiologie d. Sinne.
    Prague 1823; 2: 128.
    * Rafferty NS: Structure, function and pathology. In: Masel H, ed.
    The Ocular Lens. New York: Marcel Dekker; 1985: 2-5.
    * Sakabe I, Oshika T, Lim SJ: Anterior shift of zonular insertion
    onto the anterior surface of human crystalline lens with age.
    Ophthalmology 1998 Feb; 105(2): 295-9[Medline].
    * Schachar RA, Anderson DA: The mechanism of ciliary muscle
    function. Ann Ophthalmol 1995; 27: 126-32.
    * Schachar RA: US Patent Numbers: 5,354,331; 5,465,737; 5,489,299;
    5,503,165; 5,529,076; 5,722,952 . European and other patents pending.
    * Schachar RA: Cause and treatment of presbyopia with a method for
    increasing the amplitude of accommodation. Ann Ophthalmol 1992 Dec;
    24(12): 445-7, 452[Medline].
    * Schachar RA: US Patent Number 6,007,578 . European and other
    International Patents pending.
    * Schachar RA, Huang T, Huang X: Mathematic proof of Schachar's
    hypothesis of accommodation. Ann Ophthalmol 1993 Jan; 25(1):
    5-9[Medline].
    * Schachar RA, Bax A: The mechanism of human accommodation as
    determined by non-linear finite element analysis. (To be submitted).
    * Schachar RA, Cudmore DP: The effect of gravity on the amplitude
    of accommodation. Ann Ophthalmol 1994 May-Jun; 26(3): 65-70[Medline].
    * Schachar RA: Zonular function: a new hypothesis with clinical
    implications. Ann Ophthalmol 1994 Mar-Apr; 26(2): 36-8[Medline].
    * Schachar RA: Histology of the ciliary muscle-zonular connections.
    Ann Ophthalmol 1996; 28: 70-9.
    * Schachar RA, Tello C, Cudmore DP: In vivo increase of the human
    lens equatorial diameter during accommodation. Am J Physiol 1996 Sep;
    271(3 Pt 2): R670-6[Medline].
    * Schachar RA: Is Helmholtz's theory of accommodation correct? Ann
    Ophthalmol 1999; 31: 10-17.
    * Schachar RA, Cudmore DP, Black TD: A revolutionary variable focus
    lens. Ann Opthalmol 1996; 28: 11-18.
    * Schachar RA, Cudmore DP, Black TD, et al: Paradoxical optical
    power increase of a deformable lens by equatorial stretching. Ann
    Ophthalmol 1998; 30: 10-18.
    * Schachar RA: The scleral expansion band procedure for the
    treatment of ocular hypertension and primary open angle glaucoma. Ann
    Ophthalmol 2000; 32: 87-9.
    * Schachar RA: Pathophysiology of accommodation and presbyopia.
    Understanding the clinical implications. J Fla Med Assoc 1994 Apr;
    81(4): 268-71[Medline].
    * Scheiner: Oculus. Innsbruck: 1619.
    * Streeten BW: Zonular apparatus. In: Jakobiec FA, ed. Ocular
    Anatomy Embryology and Teratology. Philadelphia: 1982:331-53.
    * Strenk SA, Semmlow JL, Strenk LM: Age-related changes in human
    ciliary muscle and lens: a magnetic resonance imaging study. Invest
    Ophthalmol Vis Sci 1999 May; 40(6): 1162-9[Medline].
    * Sturm JC: Dissertatio de presbyopia et myopia. Altdorfi: 1697.
    * Tscherning M: Physiological Optics. Philadelphia, Pa: Keystone;
    1904:160-89.
    * V Graefe: Presbyopia: Cause and Treatment. Arch Ophthalmol 1860;
    7: 150.
    * van Alphan GWHM, Robinette BS, Marci FJ: Drug effects on ciliary
    muscle and choroid preparations in vitro. Arch Ophthalmol 1962; 68:
    111-23.
    * Vanderploeg JM: Near visual acuity measurements of space shuttle
    crew members. Aviat Space Environ Med 1985; 57: 492.
    * von Helmholtz H: Uber die akommodation des auges. Albrecht von
    Graefes Arch Ophtalmol 1855; 1: 1-89.
    * Young T: On the mechanism of the eye. Philos Trans Royal Soc
    1801; 92: 23-88.

    NOTE:
    Medicine is a constantly changing science and not all therapies are
    clearly established. New research changes drug and treatment therapies
    daily. The authors, editors, and publisher of this journal have used
    their best efforts to provide information that is up-to-date and
    accurate and is generally accepted within medical standards at the time
    of publication. However, as medical science is constantly changing and
    human error is always possible, the authors, editors, and publisher or
    any other party involved with the publication of this article do not
    warrant the information in this article is accurate or complete, nor
    are they responsible for omissions or errors in the article or for the
    results of using this information. The reader should confirm the
    information in this article from other sources prior to use. In
    particular, all drug doses, indications, and contraindications should
    be confirmed in the package insert. FULL DISCLAIMER

    Presbyopia: Cause and Treatment excerpt

    © Copyright 2005, eMedicine.com, Inc.
    About Us | Privacy | Terms of Use | Contact Us | Advertise |
    Institutional Subscribers
     
    g.gatti, Jul 2, 2005
    #6
  7. g.gatti

    g.gatti Guest

    Hallo Otis,
    see you later
     
    g.gatti, Jul 2, 2005
    #7
  8. g.gatti

    RM Guest

    Why does the best scientific evidence to date suggest that a promising
    treatment for myopia prevention in human to be overcorrection with minus
    lenses-- the opposite of what you propose, plus lenses (which by the way
    have been proven to NOT be effective)

    indeed. a very small group. apparently non of which are actually involved
    in vision research.
    no-- Rishi is a wacko. just like you and Asainmale.

    please post you "unscientific unmedical" drivel in alt.med.vision.improve
    and not here!
     
    RM, Jul 2, 2005
    #8
  9. g.gatti

    p.clarkii Guest

    so it bothers you that noone wants to engage you in irrational
    conversation?
    you are a sick pathetic old man. what other psychological problems do
    you have-- do you have a fetish for young children?
     
    p.clarkii, Jul 3, 2005
    #9
  10. Why such hysterical ad hominem arguments when someone is posting a different
    view point then your own, are you unable to use reason to counter these
    viewpoints with which you disagree ??
     
    Michael Samsel, Jul 4, 2005
    #10
  11. g.gatti

    Neil Brooks Guest

    New in town, huh?
     
    Neil Brooks, Jul 4, 2005
    #11
  12. g.gatti

    LarryDoc Guest

    And by that he means that you are unaware that the ridiculous notion put
    forth by Otis has been carefully, scientifically, factually debunked
    countless times during the two and half years the zealot has been
    posting his trash (sometime daily!) It's not that we disagree, it's
    that his theory is completely wrong and easily proven so. And,
    conversely, he cannot prove his contention at all.

    This discussion group is under the heading: sci. and med (science and
    medicine) and as such we participate in science-based discussion. "The
    Plus" is not science, is proven false and does not belong in this
    newsgroup.

    Enough said.

    Welcome to SCI.MED.Vision. Feel free to participate under that charter.

    LB, O.D.
     
    LarryDoc, Jul 4, 2005
    #12
  13. g.gatti

    p.clarkii Guest

    like the others have already mentioned, otis has been engaged in
    conversation over and over again for 21/2 years. we know all his
    arguments (which relate to chickens) and we have given him the
    references and links to the human studies. he refuses to discuss
    relevant valid scientific data, he just reposts over and over again his
    theory about plus lenses curing myopia.

    you've just walked into the middle (really the end) of a long dialogue
    where everyone is sick and tired of dealing with this troll.

    feel free to post anything here that you want that relates to science,
    or medicine, or vision, or vision research. the posters here like and
    tolerate rational people with various questions and opinions very well.
    and then there are "other" people like otis (and rishi, and asianmale)
    that have deeper psychological issues.
     
    p.clarkii, Jul 4, 2005
    #13
  14. g.gatti

    otisbrown Guest

    Dear Michael,

    It is obvious that they lack logical, scientific arguements
    to support their "position" that the natural eye is
    "dynamic".

    A rational person can accept the premise -- an argue it
    out by objective scientific testing.

    A person protecting at "standard position" simply can
    not do it -- and so must resort to "ad hominem" attacks.

    Prevention is indeed difficult -- but possible. But to
    deny it because the use of the minus lens is
    so easy -- is hardly the basic for a scientific argument.

    Best,

    Otis
     
    otisbrown, Jul 5, 2005
    #14
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.