Prosthetic eyes may not be natural, but they still require regular care to remain comfortable and attractive. If you or a family member has a prosthetic eye or may need one in the future, you'll w ...View Article
You are using an outdated browser. Please upgrade your browser to improve your experience.
There are many ways to use lenses dynamically. Standard eye care uses lenses as passive devices to compensate for some obvious symptom, which is only the end result of the real problem. This doesn’t really solve the problem; it only masks it. Dynamic lens use can help deal with the root of the problem and alleviate symptoms by addressing the causes instead of masking the end result.
< Click image to download pdf version
by Steve Gallop, O.D. (Published 1998; Journal of Behavioral Optometry, Vol. 9, #5)
Lenses are powerful tools which can enable optometry to have a tremendous impact on the well-being of human beings. This is even more critical as we move further and further into the computer age with its accompanying increased demands and stress placed upon the visual process. We can do much more that simply compensate for refractive or binocular states. Compensatory lenses are prescribed to override some aspect of the optical system of the eye. The thinking is that this will redirect light rays from a point source of light thereby placing a focused image on the fovea. With truly corrective lenses we can dynamically lead people in a positive direction as regards their overall performance. People can use lenses to prevent visual problems from manifesting. Lenses can be used to counteract adverse responses to visual stress. Obviously, they can be used to compensate for various difficulties with visual acuity, accommodation, and binocularity. This should be considered a last resort, not the primary motivation. Lenses provide a safe yet powerful means of influencing human behavior on many levels.
For the most part, standard optometric practice utilizes lenses strictly as compensatory devices. The classical approach to prescribing lenses is like the classical approach to medicine in general. For the most part both avoid dealing with the true causes. Both attempt to manage conditions by masking the symptoms in one way or another. This approach serves to remove a person’s responsibility and power. The power and responsibility are turned over to an expert and/or some external device. Undesirable side-effects often go unnoticed, or are considered inconsequential or unavoidable, and therefore acceptable. Compensating lenses may be prescribed for nearsightedness, farsightedness, and astigmatism. They may also be used to compensate for improper eye alignment and visual field defects. Surely there are patients for whom this may be the best, or even the only approach possible for various reasons. There are many ways in which lenses can be used more creatively and dynamically to benefit our patients who present with myriad complaints.1
There is a sense that optometry, as a whole, is convinced there is nothing more to learn about the art of prescribing lenses. This is due, at least in part, to the fascination with new technologies – from contact lenses to corneal reshaping. These are all exciting innovations that need not supersede a more dynamic, functional approach to vision care. It may be possible to utilize these new technologies and medical procedures within a behavioral framework. We seem content if the patient can read the bottom line on the chart regardless of other issues. There are other ways to use lenses which began with the pioneering work of people like Louis Jaques2 and A. M. Skeffington,3 and D. B. Harmon,4 who began to understand the complexity, development, and plasticity of the human visual processing system. These people realized that the strength of optometric care was not the treatment of an optical system, but of the visually guided behavior and performance of a person. People with optical systems were often found to behave in ways that were quite inconsistent with the measured optical or refractive state.5 This concept of treating the individual as opposed to the condition, or even the statistical wisdom regarding the condition, is an important issue6 in itself though it will not be directly addressed in this article.
The ability to compensate for the variety of visual conditions mentioned above is, unquestionably, of tremendous benefit within our culture. People need to be able to see clearly at all distances, under a variety of conditions, with unhesitating flexibility and accuracy as well as endurance. I think most of us would agree that making this possible is not typically a challenging endeavor. Every so often we run into an unusual case that requires a little thinking on one’s feet, but for the most part we can usually handle all problems with which we are faced. Since we seem to have this so well in hand, it is easy to gloss over other issues, prescribing the standard compensating lenses for those who come to us for no other reason. However, it is incumbent upon us to be the ones to educate the public. We are the ones who have the most thorough background in vision and lenses, not to mention our tremendous accessibility to the public. Therefore, it is up to us to achieve the highest level of understanding, and most complete knowledge of diagnostic procedures as well as available, appropriate treatment options. Only this level of knowledge will enable us to inform our patients of all the possibilities that might be available to them. We must be prepared to go the extra mile, especially when it such an easy trip. The early pioneers like Skeffington, Harmon, and others realized there was more than prescribing the best possible compensating lenses. They came to understand that lenses could also be used to stimulate visual development, prevent functional vision problems, and to improve or remediate visual problems that had already caused symptoms.
Some in behavioral optometry have maintained this philosophy to the present day. The use of bifocals and low plus lenses in children is one example. The constant use of vision at the near point is a frequent source of strain on the system. When near work is done with the addition of stress to perform at a certain level of quality, this compounds the problem even further. The judicious use of low plus lenses can provide the appropriate near lens power. This can be instrumental in preventing a more serious, long-term breakdown in visual performance for those whose visual systems have begun to show the signs of compromise.7 Although our visual systems were not designed for the type of activities that we must do to “survive” in our culture, some of us seem quite able to handle the load. A significant percentage of us, however, are unable to maintain an adequate level of performance without significant stress on the visual system. This stress will cause adverse reactions including refractive changes, breakdown of binocular integration, focusing anomalies, task avoidance, etc. Subsequent to these functional problems, there will often be more outward signs such as headaches, eye discomfort, fatigue, reduced efficiency, etc. There are also further consequences such as emotional disturbance, lowered self-esteem, and disturbance of abilities to perform work and/or social activities. The simple application of convex lenses for near, often in bifocal form, can go a long way towards reducing both the functional problem and the subsequent symptoms.8 However, more times than not, even this lens application is used in more of a compensatory way.
This is a very important issue. A compensating lens is one that is designed to take over some function that is considered to be beyond the capability of the organism at that time. The use of compensating lenses usually arises from the opinion that the condition is an irreversible one, in fact one that is likely to worsen over time. (It will continue to worsen until, for some inexplicable reason, it stops.) Since it is felt that this function cannot be adequately carried out by the individual, lenses are applied in order to do the job. This merely overrides the specific function that is not being properly handled. Such a lens does nothing to address the possible (or obvious) cause of the problem, nor does it provide any means of improving the condition. It does, in some cases, allow the person to function as though the primary complaint is absent. Compensatory prescribing is a passive response to what is considered to be a passive problem. There is neither anything in the diagnostic procedure, nor subsequent treatment that even begins to address whatever concomitant conditions may also (almost always) be present. It is unusual to find nearsightedness appearing in the total absence of any other functional issues. It tends to be no more than a single piece of the adaptive puzzle.
The visual process is a complex and dynamic one. It is not an eyeball phenomenon. There are at least a dozen pathways which branch off of the optic nerves. The visual process is not here to passively receive images. Its primary function is that of guiding action, either mental, physical, or both, in response to light. The emphasis of the function of the eyeball is not to provide an image. The eyeball acts as a gradient detector.9(p.22) Light spreads across the entire retina, mediating electro-chemical messages along the numerous subsequent pathways.10 There is no proof of the presence of an actual image on the retina, or anywhere else in the brain. In fact, there is no actual proof of the existence of photons.11 These are merely convenient ways of describing certain aspects of the world to make it easier to communicate our subjective experiences. Compensatory lenses are aimed at overriding some aspect of the optical system of the eye in order to place a focused image on the fovea. Another problem with the passive approach to lens prescribing is its lack of sensitivity to the other issues that occur when one views the world through artificial lenses.12 Take as an example a concave lens. Any time one views something through a concave lens, there is typically a change in the apparent size of the object of regard as well as the entire background. The world viewed through such a lens is displaced in space, bringing it closer to the viewer. There is therefore a compression of space in all three dimensions (which cannot occur without a corresponding change in perception of time). Whether or not the individual is aware of these changes, they are optical properties of the lens. A person habitually wearing such lenses must adapt to these changes and behave almost as if they no longer existed. However, adapting to such distortions does not make them go away. It just reduces one’s sensitivity to certain aspects, changes and distortions in our environment, both internal and external. This reduction in perceptual sensitivity can lead to further deterioration of the overall visual process. This deterioration, being a work-in-progress, will most likely proceed in the direction which has already been established. There are also more fundamental, more subtle changes which frequently occur as a result of the habitual use of compensatory lenses. Spectacle lenses also encourage head rather than eye movement due to various distortions that occur away from the optical centers of the lenses. This causes reduced efficiency, more rapid visual fatigue, and a tightening of the neck muscles as well as the extraoculars. There are other issues which are less critical to the current discussion.
Many people come to my office with an expressed desire to reduce the strength of their lenses, and their dependence on them. This is an unusual group of people since the majority of those seeking eye care just assume that what they have been told is the only possibility. More and more people are putting themselves in this category, even with the advent of surgical alternatives. They have typically been told that their condition is genetic, irreversible, unchangeable, and can either get worse or stabilize. This group seems unconvinced of these pronouncements of doom. In addition, there are numerous individuals who have found their way into my office with no preconceived notion of reducing the power of their lenses. Most are presenting with some type of complaint which they may or may not associate with their prescription, or even their eyes. Once an association between the complaint and some aspect of the visual process can be established, their thought process begins to shift. Then, when they hear that there are in fact alternatives to the standard approach to prescribing and utilizing lenses, one that may very well positively impact on their situation, many are interested in trying another way. Most will reveal that they have always wondered if there wasn’t some other possibility. However, if you go to an expert who tells you what you expect to be the whole truth and nothing but the truth, that will typically serve to satisfy you. If we don’t trust our doctors, it makes health care much more difficult. Therefore, we have a tendency to accept much or all of what we are told by our doctors.
When a nearsighted individual is wearing standard compensating lenses based on optical findings, on a constant basis, they are overworking their visual system up to 90% of the time. Such a prescription is aimed at full distance acuity, that is, best visual acuity at twenty feet (optical infinity) and beyond. Very little of our time is spent viewing at such distances during our normal routine. Most of us are spending most of our time indoors where viewing distances typically range from sixteen inches to fifteen feet. Every so often we are called upon to view at greater distances, but these situations are usually of brief duration. There is no question that some people have different needs and should be cared for accordingly. Some people need the full compensating prescription to feel comfortable and secure, and to function most effectively in their every day environment. Unfortunately, it is all too easy for most people to wear full-strength, compensating lenses on a full time basis, seeing clearly at all distances with apparent ease. I say unfortunately for the following reason. There are many times when a less than optimal tool is used to complete a task. The job may get done adequately without the proper tool, and in a pinch, sometimes one must make due. If the task becomes repetitive, or of long duration, the proper tool may become a necessity. For example, it is entirely possible to use a sledge-hammer to hammer in a nail. The sledge-hammer has all the necessary components to get the job done. It has a handle and a hard, flat head. Hammering in one nail with this tool can be done quite easily. In fact, with some practice, one could become quite adept at hammering in nails with a sledge-hammer (just don’t miss). Repetitive use of this tool for this task could have various consequences. There could be increased muscle density in the arms, there could be arm fatigue, or there could be some sort of repetitive motion disorder. The bottom line is the fact that there are much better tools for this kind of job. Similarly, the full distance prescription for nearsightedness is a kind of optical sledge-hammer. Using this tool will not lead to increased muscle density in the eyes; it will only lead to increased visual stress and a continuation of the behavior and subsequent adaptive process which initially caused the adverse response that is nearsightedness.
As the human organism adapts to stress, trying to solve problems of efficient visual behavior, various patterns of function are attempted, perhaps randomly, to make the job go easier – in the present moment. This is analogous to the growth of a plant. A plant growing straight up will change its growth pattern if its exposure to the sun is impeded; it may bend in any of a number of directions attempting to regain maximal exposure. Without direction and guidance, the endless possibilities are accessed and attempted, in various patterns, with varying emphasis on different components and possibilities.13 In the human version, whatever is changed at that moment, to bring comfort and relief, may be kept at the ready for the next moment. If it works again, it becomes a useable solution and then a behavior pattern. A few moments down the road may expose a slightly, or dramatically different problem to solve. This may lead to a modification of the previous solution or a totally new solution/behavior pattern. It may also lead to an attempt to utilize the previous modification to carry out this new task. The full-scope success or failure of this maneuvering is more or less a matter of chance unless there is some guidance of the process based on an understanding of all the factors involved.
This process repeats itself at many moments and in many ways. In the plant analogy this will produce changes in growth patterns. If the difficulty is sufficiently great and prolonged, it can lead to structural damage or worse. The obstruction can be removed at any point, and kept away allowing growth to proceed normally from that point onward. However, by then, the structural changes may be physically embedded. Support mechanisms can be instituted to minimize the impact of the structural damage such as tying the plant to an sturdy external pole; this will maintain a sufficiently upright posture. These same types of things may happen very early on in human life and unless there is some type of closure, some true resolution that works for most moments and most problems, this process may continue indefinitely. Most often there is some type of closure which, if unguided, typically results in a resolution that is inefficient and cumbersome although better than a free-floating state with no standard operating procedure. The supporting pole, in the human version, might be a therapeutic lens. This might not completely reverse the structural changes, but may be sufficient to allow performance to proceed more normally from that point onward.
All optometric findings reveal the outward signs of some adaptive visual process. Our findings do not represent the visual problem. They represent the direction and style of a person’s response to a visual problem. This is the typical relationship between outward signs and symptoms of illness, and the actual disease process.6 Most visual findings are the result of a person’s inability to handle the load placed on the visual system by some task or demand. In order to come to terms with the demand, some adaptation must be made if things are not going smoothly. The most common, most practical adaptation is the move to become nearsighted. The person gives up distance acuity in favor of creating a new far-point of focus, one that provides much less demand when viewing at short distances. Starting at an early age, the near viewing distance is the one which occupies most of our time. It is also the place where our performance tends to attract the most scrutiny whether it be school or job related performance. There is a lot of stress associated with performance at the near viewing distance. It therefore makes sense to make this type of activity as easy as possible. The move toward nearsightedness is both clever and effective in this regard. Were it not for the degradation in overall visual performance that typically results, this adaptation would be an excellent aid to achievement within our culture.
Someone who has begun this adaptive maneuver is typically taken for an eye exam, and found to be unable to achieve normal distance acuity. Based solely on this factor, lenses are provided to reestablish the clinically acceptable acuity. These lenses do not take into account the individual’s true every day needs. Neither do they address the true causes of the active process creating this outward sign. They are strictly seen as a means of providing so-called necessary distance acuity. The prescription is based solely on the outward signs at that moment. It cannot be overemphasized that the outward signs seen during an eye exam or visual evaluation point to the individual’s attempt at a solution, not the problem. What we see is the modification that has been made in order to fit in, achieve, and survive. Another problem is that more and more eye exams rely more and more on technicians and automated devices to make measurements14 which, if done personally, might reveal much useful information. Such information may be critical in gaining a comprehensive understanding of a patient’s true condition, needs, and the best way to treat the whole person. Neither ancillary office personnel nor autorefractors provide even a tiny fraction of the information available through distance and near retinoscopy performed by a skilled optometrist.
It is possible to prevent the onset, slow down, or reverse the progression of nearsightedness, farsightedness, and astigmatism. In all cases, it is a matter of looking at these conditions as results of some fundamental difficulty with visual processing. The most powerful tool for bringing about positive changes in visual processing is a low powered convex lens. The use of appropriate plus lenses, with or without the benefit of vision training, can go a long way towards normalizing binocular and accommodative function, visual spatial perception, and peripheral visual awareness. This type of lens differs from a compensating lens in many ways. It is not aimed at directly improving acuity at any distance. It is not designed to take over some function of the optical system. It will serve to enhance overall visual function, and will lead to positive changes over time, if prescribed and used properly. These lenses are not prescribed based on a single finding (change in distance acuity). They are based on some type of thorough functionally-based evaluation of the visual process, an understanding of the underlying process of adaptation, and a complete evaluation of the actual visual performance demands of the individual.
Lenses are a type of medicine (Medicine n. 1) any substance, drug, or means used to cure disease or improve health.)15 even though they are not taken internally. They can promote changes in behavior, or effect they way one feels. Appropriate near lenses can affect positive changes in school performance and work performance as well as overall behavior. These lenses can also bring about changes in a person’s level of comfort by eliminating eyestrain, eye pain, or headaches. While in some cases compensating lenses can be seen to provide some of these same benefits, these changes are typically seen only when the lenses are being worn. This is not unlike some types of internally taken medications. They are effective only during an active phase, and when this phase elapses the symptoms return. In the majority of cases therapeutic lenses will create more long lasting changes. In fact, it is generally the case that such changes will become permanent since the primary action of the lenses is to affect internalized changes in behavior and performance.
When used in very small amounts, convex lenses, yoked prisms, bases out and bases in prism can have an effect which is analogous to the effects of internally taken homeopathic medicines. Homeopathic preparations are designed to stimulate the body’s own mechanisms for healing. Homeopathic medicine uses like to treat like. It uses what is typically considered to be an insignificant amount of a substance which, when introduced into the body, stimulates learning by the immune system. This enables the system to respond more effectively in similar future situations.16 This is not like an immunization which uses more significant amounts of a substance to trigger an actual response to the toxin. This can cause an actual illness from the exposure, and does so, in a percentage of cases.
Low powered lenses and prisms create a slight change in the distribution of light on the retina as well as gently altering spatial perception. This alteration of space occurs in all three axes of space, that is, there is a change in the wearer’s relationship to the entire three-dimensional space volume they inhabit. Every action takes place in space, and over a period of time. (There is the time it takes to process the information, the time between input and response, and the time it takes to actually carry out the response.) Therefore, anything that affects space also affects time.
Standard compensating lenses and prisms are allopathic in nature and function as a crutch by essentially taking over the work that the visual system is unable to carry out effectively. They serve to mask the actual problem by creating the illusion of more accurate input. When these lenses are not being worn, there is no improvement in visual performance. In fact, there is typically a reduction in performance over time which creates the need for stronger compensation. This is true in cases of nearsightedness, farsightedness, astigmatism, and strabismus. Due to the intimate relationship between vision and behavior, it is important, if not necessary, to attempt to directly influence behavior (at least visual behavior) through visual input and processing. Compensating lenses, if they do influence behavior, do so in two ways that run counter to homeopathic philosophy. They are prescribed by measuring the magnitude refractive error, or of binocular misalignment to place an image on the fovea. This serves to ignore the root of the problem, and in fact, will often stimulate the visual system to continue the same process of adaptation as before. This approach typically forces the wearer to change behavior by becoming “one with” the compensatory device. That is, by giving in to the demands of the device, by resigning oneself to a certain level of dependence on the device, one makes internal changes to become more comfortable with, and more adept at utilizing the device. This often necessitates increasing the strength of the compensating lens over time.
The homeopathic approach to lens usage stimulates a gentle change in the wearer’s relationship to the environment. This serves to provide an option, or options, to perceiving and responding to the environment. Typically, these devices can be removed, once the learning they stimulate has occurred, and the desired changes will remain. This will most likely occur when the change is positively received, which indicates that it is of benefit to the individual. Subconsciously, we are constantly searching for the path of least resistance and most effectiveness. We also need to feel good about the person with whom we have chosen to work, and their approach. “The power of the mind is such that when you take medicine with the understanding and trust that this medicine has some property that is going to work, this gives confidence and peace of mind. The combination of mind and medicine speeds recovery.”17 It is difficult to achieve this if we do not have options from which to choose. Without a broader context, we can only know what is available to our awareness. When there are choices available to us, we have power to select what suits us.
As a result of Skeffington’s ideas, energy, and communication skills, the discipline of behavioral optometry was fortunate to avail itself of a more thorough means of visual analysis. This led to improved ability to prescribe what may be the most potent tool for the safe, judicious, and gentle manipulation of visual performance, which in turn effects overall behavior. The ability to utilize lenses for the enhancement of visual performance, or the prevention of visual problems, need not be the exclusive domain of so-called behavioral optometrists.18 In fact it is too important a concept to remain unused by the vast majority of those prescribing lenses on a daily basis. The accurate diagnosis and subsequent treatment of functional visual disorders through the use of therapeutic lenses19 represents a state-of-the-art technique which should be as much a part of the so-called “standard of care” as procedures like retinal photography, automated perimetry, and the use of therapeutic pharmacological agents.
In fact, the possibility of preventing visual problems, reversing adverse visual adaptations, and guiding developmental processes through the use of ophthalmic lenses is like a rare antique buried in the attic of optometry. Uncovering this gem could rejuvenate and differentiate the profession of optometry in many ways, not the least of which is the potential for greatly increased income. If the profession as a whole would embrace the developmental, stress relieving, preventive, and performance enhancing capabilities of lenses, we would see more patients, more often. We would also be dispensing more glasses than we ever imagined possible. The goal here is not to simply increase our collective income however. The goal is to provide the highest possible level of care to the greatest number of people. For some the behavioral philosophy includes the concept that everyone who spends time reading, writing, or sitting at a computer should be wearing lenses that help the visual system cope with activities for which they were not designed.1,2,3,8,19 These are the same activities that are causing epidemic visual breakdown in people of all ages. Just imagine if the level of professional and public awareness was such that all were aware of the importance of lenses not only to prevent problems, but to increase comfort, productivity, and stamina in visual performance. This would put just about everybody in our offices, not just those who were experiencing difficulty. More importantly, there will be a tendency for people to experience significant improvement in visual performance instead of the tendency for needing stronger compensating lenses every 6-12 months. We would see an almost staggering increase in the number of patients we see since most people never get their vision evaluated until presbyopia surfaces.
A similar phenomenon has already occurred in dentistry. For many years the tendency was for people to visit the dentist when they felt something was wrong with their teeth. In more recent times the profession made a public education push to get people into their dentist’s office for preventive care. In fact, preventive dental care is covered by insurance. This not only increased the income of dentists everywhere, but has raised the level of dental health tremendously. This has been achieved in two ways. First, are the new methods of coating children’s teeth periodically to protect them from getting cavities in the first place. Second, is the trend towards bi-annual cleanings to keep teeth in a healthier state. If optometry could unite on the issue of visual hygiene via proper lens use (and other related precautions such as posture, lighting, etc.) and proceed to educate the public, we could find ourselves at a new level of public demand and respect. We need to get the public and the profession to think of vision care as a positive thing. This would also help differentiate our profession at a time when we are in serious danger of being absorbed into the discipline of ophthalmology. We can channel the development, effectivity, and comfort of visual performance instead of waiting around until people come to us with serious problems.
The real importance of the ability to affect positive changes via ophthalmic lenses is the fact that the visual process is the most important interface between a person and her environment. This environment includes both internal territory as well as the external terrain.19 We must successfully navigate through both sectors of our environment throughout our lives. It is vital to have a highly accurate and flexible means of interpreting our world in order to achieve the highest level of performance, with maximum comfort and efficiency, if we are to hold our own in a fast paced, visually demanding, and visually stressful culture. In addition, our perceptions of the external world effect our internal perceptions in many ways. Improved visual performance and reduced visual stress will have positive repercussions in all areas of our lives.
1. Kraskin RA. How To Improve Your Vision. North Hollywood: Wilshire Book Co., 1968.
2. Jaques L. Corrective and Preventive Optometry 1950. Los Angeles: Globe Printing Co., 1950.
3. Skeffington AM. Practical Applied Optometry. Optom Extension Prog; Ed by Hendrickson H,1991:83.
4. Macdonald LW. The Collected Words of Lawrence W. Macdonald, O.D. Vol. 1, 1954-1965. Santa Ana: OEP, 1992.
5. Shankman AL. Vision Enhancement Training. Santa Ana: OEP, 1988.
6. Galland L. Four Pillars of Healing. Random House, 1977.
7. Press LJ. Applied Concepts in Vision Therapy. St. Louis: Mosby, 1997.(p. 251)
8. Birnbaum MH. Optometric Management of Nearpoint Vision Disorders. Boston: Butterworth-Heinemann, 1993.
9. Harmon DB. Notes on a Dynamic Theory of Vision. 1958.
10. Gallop, S. Peripheral visual awareness: the central issue. J Behav Optom. 1996;7(6):151-5.
11. Bohm D. Hiley BJ. The Undivided Universe. London:. Routledge, 1993.(p.176-80)
12. Orfield A. Seeing Space: Undergoing Brain Re-programming to Reduce Myopia. J Behav Optom. 1994;5(5):123-31.
13. Kraskin RA. Personal communication.
14. Cole RM. Hand off refraction without handing off control. Review of Optom. May 15, 1998:59-62
15. dictionary def. Of Medicine
16. Ullman D. The Consumer’s Guide to Homeopathy. New York: G. P. Putnam’s Sons, 1995.
17. Johnson S. The Book of Tibetan Elders. New York: Riverhead Books, 1996.
18. Kraskin RA. Lens Power in Action. Santa Ana: OEP, 1982.
19. Ong E. Ciuffreda K. Accommodation, Nearwork and Myopia. Santa Ana: OEPF, 1997.
20. Gallop S. Myopia Reduction…A View From the Inside. J Behav Optom. 1994;5(5):115-20.