Symposium Paper

Colored Lenses to Improve Mitchell Scheiman, OD Reading Comfort and Performance: Are Underlying Vision Problems being Missed?

Optometrists have raised concerns about the use of Irlen filters/ lenses because of the striking similarity between the symptoms associated with accommodative, binocular and ocular motility disorders and the symptoms associated with the scotopic sensitivity syndrome described by Irlen. This article provides evidence demonstrating that Irlen filter candidates often have unidentified vision disorders, that optometric treatment alone can often eliminate these symptoms, that the Irlen evaluation does not adequately account for the presence of underlying vision problems, and that few research studies have adequately controlled for the presence of underlying vision problems. It is evident that many patients are receiving substandard eyecare resulting in undetected accommodative, binocular vision, and ocular motor disorders. Because these patients are still symptomatic they seek other remedies. This appears to be the population of people who are seeking help from colored filters. Although there is some evidence to indicate a potential role for the use of colored filters in the treatment of individuals with reading problems, it is incum- bent on both researchers and clinicians to ensure that vision problems are adequately addressed before colored filters/lenses are used. Key Words: colored filters, Irlen filters, scotopic sensitivity syndrome, binocular vision, accommodation, oculomotility disorders.

Over the past 2 decades, the use of colored clinicians are confronted with patients seek- or tinted lenses to improve reading comfort ing advice about the value of colored lenses and performance has become a prominent is- and possible treatment. Meares1 and later sue in both the popular media and profes- Irlen2 described a syndrome of visual symp- sional literature. With increasing frequency, toms and distortion that can be alleviated with colored filters. In addition, investigators Correspondence regarding this article should claim that the required tint is idiosyncratic 1,3–7 be addressed to Mitchell Scheiman, OD, Pennsyl- and needs to be highly specific. The term vania College of Optometry, 1200 West Godfrey Ave, “scotopic sensitivity syndrome,” was intro- Philadelphia, PA 19141. E-mail: mscheiman@ duced by Irlen2 and described as a perceptual pco.edu dysfunction related to subjective difficulties

Volume 35 / Spring 2004 37 with light source, luminance, intensity, wave- This article is designed to explore the fol- length, and color contrast. More recently, Irlen lowing issues: has referred to the syndrome as the “Irlen 1. Do Irlen filter candidates simply have un- Syndrome.”3 According to Irlen, individuals identified vision disorders? with this condition must use more effort and 2. What is the effect of optometric interven- energy when reading because they are ineffi- tion on symptoms of candidates for Irlen cient readers who see the printed page differ- Lenses? ently from the good reader. The difficulties 3. Does the current Irlen evaluation ad- they experience may lead to fatigue, discom- equately account for the presence of under- fort, and inability to sustain attention for suf- lying vision problems? ficient periods of time, sensitivity to light, eye- 4. Have research studies on the use of colored strain, difficulty focusing, unstable appear- filters adequately ruled out the presence of ance of the print, words moving on the page, vision problems? and words appearing washed out.3 3 Irlen claims that approximately 50% of Do Irlen Filter Candidates Simply Have the reading disability and dyslexic popula- Unidentified Vision Disorders? tions have this syndrome and that this is a key factor interfering with the reading process in Scheiman, Blaskey, Ciner, et al.12,18 inves- these individuals. She suggests that close to tigated this specific issue and reported that identified as good (39 ס of individuals with this disorder can be 95% of subjects (N 90% successfully treated using appropriately candidates for Irlen filters had significant, tinted lenses, called “Irlen Filters/Lenses.” readily identifiable vision anomalies. Fifty- The objective of this treatment procedure is seven percent of the subjects had binocular vi- both to eliminate the discomfort associated sion problems, 34% had accommodative prob- with reading and to improve reading perfor- lems, 26% had ocular motor dysfunction, and mance. Irlen3 also suggests that Irlen syn- 29% had miscellaneous problems such as un- drome is a distinct entity that cannot be iden- corrected or improperly corrected refractive tified through standardized educational and errors, and uncorrected presbyopia. Lopez, psychological evaluations, vision examina- Yolton, Kohl, et al.13 also investigated this is- tions, medical checkups, or other standardized sue. They found a high percentage of patients diagnostic tests. requiring colored filters were vision therapy Optometrists and ophthalmologists8–15 candidates. have raised a number of concerns about Irlen’s It is important to stress that Irlen advo- theories and methods. The first issue is the cates specifically claim that scotopic sensitiv- striking similarity between the symptoms ity syndrome is an entity which is distinct that Irlen suggests are associated with scoto- from vision problems that could be identified pic sensitivity syndrome and the symptoms in an optometric evaluation. The Irlen bro- associated with accommodative, binocular chure implies that each client first receives a vision, and ocular motility disorders. Specifi- complete vision examination and that vision cally, the following symptoms have been problems are treated prior to Irlen diagnostic reported to be associated with both scotopic testing. The study by Scheiman, Blaskey, sensitivity syndrome16 and the vision prob- Ciner, et al.12 addresses this issue. They found lems12,17 listed above: headaches, eyestrain, that 57% of their subjects either had periodic excessive blinking, excessive rubbing of the vision care or at least 1 eye examination eyes, squinting, intermittent blur, occasional within a year of the study. Of these subjects, double vision, movement of words on a page, 90% had significant uncorrected vision prob- frequent loss of place, skipping lines, inability lems. to sustain and concentrate, and rereading the It is apparent that simply recommending same lines unintentionally. Could subjects di- an eye examination is insufficient to rule out agnosed as having “scotopic sensitivity syn- accommodative, binocular vision, or ocular drome” simply have refractive, accommoda- motility disorders; it is also necessary that ap- tive, binocular vision, or oculomotility disorder propriate testing be performed to detect the that has not been properly diagnosed? underlying vision disorders. This suggests 38 Journal of Optometric Vision Development that the quality of eye care that is being pro- alone was an effective method of reducing the vided is less than optimal. The “syndrome” discomfort reported by these subjects. This discovered by Irlen, may simply be the discov- suggests that scotopic sensitivity syndrome ery of a large segment of the population that is may not be a distinct syndrome and that many receiving inadequate vision care. Eye care pro- individuals identified as candidates for Irlen fessionals are apparently not incorporating ac- lenses have significant, undetected vision dis- commodative, binocular, and ocular motility orders requiring treatment. testing in routine evaluations, even when patients present with symptoms characteristic of Does the Current Irlen Evaluation Not disorders in these areas. Any non-eye care pro- Adequately Account for the Presence of fessional would reasonably assume that a Underlying Vision Problems? negative result from previous eye examination The Irlen evaluation consists of 2 parts. means the absence of any significant vision Part 1 is a screening to determine if the pa- problem. Irlen’s naming of the complex of tient has scotopic sensitivity syndrome and if signs and symptoms “scotopic sensitivity syn- colored overlays are beneficial. If colored over- drome” or Irlen syndrome is understandable. lays are beneficial, these are prescribed and However, another possible name to more aptly used for several weeks. If the patient reports describe these patients would be “Comprehen- that the overlays have been helpful, Part 2 of sive Eye Examination Deprivation Syndrome” the Irlen Evaluation is scheduled and involves (CEEDS). There appears to be a large popula- an evaluation to determine the appropriate tion of individuals who are receiving substan- tint to incorporate into eyeglasses. This pro- dard vision care. After an eye doctor informs cess is similar to the subjective evaluation them that their eyes are fine, they naturally used by optometrists during the subjective re- seek care from other individuals and may sub- fraction. This entire sequence of testing, how- sequently be mistakenly identified with “Irlen ever, is based on the basic assumption that the syndrome.” patient has already had a comprehensive eye It is, therefore, apparent that there is a examination and vision problems have been large population with unmet vision needs that ruled out as a basis for any remaining symp- have turned to the Irlen treatment approach toms experienced by the patient. for help that they failed to receive from eye In “Reading by the Colors,”3 Irlen states: care professionals. “Individuals interested in being screened for SSS should first see an optometrist or ophthal- What Is the Effect of Optometric mologist and receive a complete visual exami- Intervention on Symptoms of nation.” Although it is a reasonable for a naı¨ve Candidates for Irlen Lenses? observer to assume that any comprehensive Only the study by Blaskey, Scheiman, Pa- eye examination will rule out any vision prob- risi, et al. has addressed this issue.18 They per- lem, Irlen and her associates, based on the re- formed a randomized clinical trial to compare search described earlier, should now be famil- the effectiveness of Irlen filters vs optometric iar with the notion that this is generally not intervention for improving the symptoms of the case. Irlen lens candidates. Subjects were random- Some authors do raise doubt about the rou- ized into an Irlen treatment group, an opto- tine eye examination. In “The Light Barrier” metric treatment group, and a control group Stone19 states: “Typical vision evaluations test (no treatment). Patients randomized into the only for a few learning-related visual skills optometric treatment group were treated with (distance visual acuity, stereo vision, and lenses and/or vision therapy and showed sig- muscle balance), leaving most visual skill de- nificant improvement in comfort. Before opto- ficiencies undiagnosed.” However, this author metric intervention all subjects would have does not go far enough to alert the reader to been considered candidates for Irlen lenses. inquire about the doctor’s credentials and phi- After optometric treatment, the Irlen test losophy before scheduling the examination. scores dropped to a point at which they would Wilkins who is a strong advocate of the use of not have been considered to be candidates for tinted lenses to improve reading comfort and Irlen lenses. Thus, optometric intervention performance20 states: “It is therefore essential Volume 35 / Spring 2004 39 that anyone who experiences the symptoms SUMMARY listed above or has difficulty reading obtains an examination from an optometrist. If they The only research studies that have con- recommend eye exercises, these should be trolled for the presence of vision anomalies taken seriously.” He goes on to stress that it is have demonstrated that a large percentage of important to ask the optometrist whether they patients that believe they would benefit from will do certain tests before booking an appoint- Irlen filters actually have significant undetected and uncorrected vision disorders. Another ment. The recommended tests are Mallet fixa- 18 tion disparity, fusional reserves at near, and study showed that once treated with appro- accommodative lag. Although the use of these priate lenses and vision therapy they become tests may be an improvement over the testing comfortable and their attention, concentra- battery used by most optometrists or ophthal- tion, and sustaining ability improved when mologists, it is certainly not sufficient to rule reading. Advocates of tinted glasses have out binocular vision, accommodative, and ocu- made a critical error in suggesting that they lar motor disorders. can rule out vision disorders simply by assur- Based on this information it is clear, that ing that all of their clients first have a vision as currently designed, the Irlen evaluation examination. Irlen and other advocates of the does not adequately rule out the presence on use of colored filters and lenses to treat read- an underlying vision problem. ing problems must begin to realize that all vision examinations are not identical and that to rule out a vision disorder they must make a Have the Research Studies on the Use referral to a professional who will perform ap- of Colored Filters Adequately Ruled Out propriate testing. Testing must include a thor- the Presence of Vision Problems? ough assessment of refraction, accommodation From an optometric perspective, a problem (amplitude, facility, and response), binocular with almost all research to date has been a vision (eye alignment, fusional vergence, and lack of attention to underlying vision disor- vergence facility), and ocular motility (sac- ders. Blaskey, Scheiman, Parisi, et al.18 com- cadic speed and accuracy). pleted a study of Irlen filters that did include It is also important to realize that there is a comprehensive assessment of vision as part some research to indicate that there are occa- of the experimental design. As reported above, sions in which the use of tinted lenses may identified as good help patients even after they have been (39 ס of subjects (N 95% candidates for Irlen filters had significant, treated with lenses and vision therapy. Re- readily identifiable vision anomalies. In most searchers must continue to carefully investi- studies,4,21–26 the only effort to ensure the ab- gate this phenomenon. However, in future sence of underlying vision problems has been studies it is imperative that subjects be ad- requiring subjects to have an eye examination equately evaluated for underlying vision prob- before entering the study. Other studies have lems. made an attempt to screen subjects for vision Finally, research on Irlen filters has dem- problems prior to enrollment in the study. onstrated that many eye care professionals However, all of these studies have failed to are not providing optimal care for their pa- adequately screen for binocular vision, accom- tients. It is clear that many patients with ac- modative, and ocular motor anomalies.5,27–31 commodative and binocular vision disorders They have failed to include tests such as ac- are not being properly managed. 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