Glasses compensate for myopia in that they create clear distance vision. They do not cure myopia since the blurred distance vision returns as soon as the glasses are removed. People become myopic before they obtain glasses and many continue to become more myopic as the years progress.
Can specialized glasses do anything to actually cure or slow down myopia? Research continues, but is showing that specialized glasses, such as multifocals have limited benefit. Radial refractive gradiant glasses (MyoVision TM) have not made it to the published results stage, presumably because of poor results. There is now one study in animals showing that high plus lenses worn one hour a day are protective against myopia progression.
Are normal glasses actually making myopia worse? This is difficult to answer because the control in most studies is considered to be the glasses wearing patient. One way to look at it however is to assume that vision care had evolved so that orthokeratology was the default treatment for myopia. If someone were to then "invent" glasses, they would have to argue as to their appropriateness when glasses are shown to make myopia approximately twice as bad for the young myope.Neville A. McBrien, Baskar Arumugam and Sangeetha Metlapally. (2012) The Effect of Daily Transient +4 D Positive Lens Wear on the Inhibition of Myopia in the Tree Shrew. (FULL TEXT) Investigative Ophthalmology & Visual Science VOL 53 no. 3 PG 1593-1601 doi10.1167/iovs.11-7859
MyopiaPrevention.org comment: Tree shrews, a small primate, were made myopic by the use of diffuser lenses over their eyes. It was found that short periods (one hour a day) of high plus lenses effectively cancelled out the myopic progression. Although only an animal study and only with artificially induced myopia, it holds the promise that correctly designed intervals of high plus power could slow myopia, even for those wearing their normal myopia glasses. Such lenses would create blur at all distances for the wearer and so the design of a beneficial wearing schedule would need to be determined, if in fact this modality actually works in humans.David A. Berntsen, Loraine T. Sinnott, Donald O. Mutti and Karla Zadnik. (2011 ) A Randomized Trial using Progressive Addition Lenses to Evaluate Theories of Myopia Progression in Children with a High Lag of Accommodation . (ABSTRACT) Investigative Ophthalmology & Visual Science Published online before print December 28, 2011, doi: 10.1167/iovs.11-7769
MyopiaPrevention.org comment: Another study that indicates progressive addition spectacle lenses are not clinically effective in slowing myopia, even in patients with a lag of accommodation and a near esophoria.Donovan L, Sankaridurg P, Ho A, Naduvilath T, Smith EL 3rd, Holden BA.(2011) Myopia Progression Rates in Urban Children Wearing Single-Vision Spectacles. Optometry and Vision Science POST AUTHOR CORRECTIONS, 6 October 2011 (ABSTRACT) doi: 10.1097/OPX.0b013e3182357f79
MyopiaPrevention.org comment: Not a whole lot new here but it's nice to see a summary - this is a meta-analysis (meaning it looks at lots of studies) of just what the title says. At an age of 9.3 years old, "European extraction" children progressed at -.55 Diopters per year and Asian students progressed at -.82 Diopters per year. Younger children and females progressed faster.Jane E. Gwiazda. (2011) Progressive Addition Lenses versus Single Vision Lenses for Slowing Progression of Myopia in Children with High Accommodative Lag and Near Esophoria. (FULL TEXT) Investigative Ophthalmology & Visual Science April 2011, vol. 52 no. 5 pp 2749-2757 iovs.10-6631 doi: 10.1167/iovs.10-6631
MyopiaPrevention.org comment: The conclusion says it all: " The PALs used in this study were found to have a statistically but not clinically significant effect on slowing myopia progression in children with high accommodative lag and near esophoria. " In other words, they didn't work.Desmond Cheng, George C Woo, Katrina L Schmid. (2011) Bifocal lens control of myopic progression in children. (FULL TEXT) Clinical and Experimental Optometry Volume 94, Issue 1, pages 24–32, January 2011 DOI: 10.1111/j.1444-0938.2010.00510.x
MyopiaPrevention.org comment: This is a review of prospective and retrospective studies on multifocals for treatment of myopic progression along with a discussion of what the combined information might mean for future treatments. In general, the studies show that multifocals have little effect except for a subset of children with some combination of high lag of accommodation, high rate of progression and esophoria. The authors argue for a customization of the add given to individual patients, with the goal being to reduce both the accommodative lag and near phoria as much as possible through the prescribed add. When the add is large enough to eliminate accommodative lag, many children have a large exophoria for which the authors suggest base in prism.Liu Y, Wildsoet CF. (2010) The Effect of 2-zone Concentric Bifocal Spectacle Lenses on Refractive Error Development and Eye Growth in Young Chicks. (ABSTRACT) Invest Ophthalmol Vis Sci. 2010 Sep 22. [Epub ahead of print]
MyopiaPrevention.org comment: Concentric bifocal lenses with different combinations of plano central or peripheral powers combined with plus and minus centrally and peripherally. Also various sizes of zones. Quoting the conclusion: "The results demonstrate that peripheral defocus can influence both peripheral and central refractive development. The inhibitory effect on axial eye growth of the +5P lenses opens the possibility that appropriately designed concentric lens designs may control progression of human myopia." (A +5P lens had a plano center zone combined with a +5.00D peripheral power.)Sankaridurg, Padmaja; Donovan, Leslie; Varnas, Saulius; Ho, Arthur; Chen, Xiang; Martinez, Aldo; Fisher, Scott; Lin, Zhi; Smith, Earl L. III; Ge, Jian; Holden, Brien.(2010) Spectacle Lenses Designed to Reduce Progression of Myopia: 12-Month Results. (FULL TEXT) Optometry & Vision Science September 2010 - Volume 87 - Issue 9 - pp 631-641
MyopiaPrevention.org comment: Lenses with radial refractive gradients of various designs were tested for their ability to retard myopic progression. The lenses were manufactured by Zeiss and are presumably possible MyoVision designs, although this was not stated. One of the three tested designs was able to slow progression about 30% for children having at least one myopic parent. The lens design was asymetric, with 1.9 D of additional plus power 25mm "from the axis in (the horizontal meridian)". An effect was also found in younger females.Cheng D, Schmid KL, Woo GC, Drobe B. (2010) Randomized trial of effect of bifocal and prismatic bifocal spectacles on myopic progression: two-year results. (FULL TEXT) Arch Ophthalmol. 2010 Jan;128(1):12-9
MyopiaPrevention.org comment: In a two year study of 135 Chinese Canadian myopic children whose myopia progressed during the previous year at least .50 diopters, children with regular glasses progressed 1.55 units (100%), students with bifocal glasses progressed .96 units (62%) and those with bifocals and base-in prism progressed .70 units (45%). The bifocal used were executive bifocals which have a larger reading area than regular progressive lenses. The demonstrated ability to slow myopia is comparable to other studies of ortho-k's ability to slow myopia.Lin, Zhi; Martinez, Aldo; Chen, Xiang; Li, Li; Sankaridurg, Padmaja; Holden, Brien A.; Ge, Jian (2010) Peripheral Defocus with Single-Vision Spectacle Lenses in Myopic Children. (FULL TEXT) J Optometry and Vision Science: January 2010 - Volume 87 - Issue 1 - pp 4-9
MyopiaPrevention.org comment: Regular glasses are shown to create peripheral hyperopia, and "Although the effect of this induced hyperopia on the progression of myopia at the fovea remains to be assessed, it is reasonable to suppose that improving on the designs of the existing optical interventions may confer additional benefits." In other words, regular glasses for myopia create conditions that have been shown to increase myopia, so it would be wise to design better glasses.P.R. Sankaridurg, L. Donovan, S. Varnas, X. Chen, Z. Lin, S. Fisher, A. Ho1, J. Ge, E. Smith, B.A. Holden.(2010) Progression of Myopia With Spectacle Lenses Designed to Reduce Relative Peripheral Hyperopia: 12 Months Results. (ABSTRACT) Presentation at ARVO 2010 Program #2206, Poster #A305
MyopiaPrevention.org comment: A poster presentation. Although not stated in the abstract, this should be the lens now advertised in Asia as the MyoVision lens. It is the first Radial Refractive Gradient lens on the market and you can read more about it under the Treatments-Lenses-RRG Glasses menu. Three types of RRG lenses were used One of the three types (the "rotationally asymmetric AMSPL") was found in the subset of younger children with at least one myopic parent to reduce progression by 30% over a one year period.Tabernero J, Vazquez D, Seidemann A, Uttenweiler D, F. (2009). Effects of myopic spectacle correction and radial refractive gradient spectacles on peripheral refraction. (ABSTRACT) Vision Res. 2009 Aug;49(17):2176-86. Epub 2009 Jun 13
MyopiaPrevention.org comment: Conventional glasses produced peripheral hyperopia, Radial Refractive Gradient (RRG) lenses that give increasing plus in the periphery in all directions produced peripheral myopia, but the RRG lens introduced distortions that "would probably limit the direct use of the RRG lenses as currently designed." There was a wide variation of measured hyperopia in the periphery for myopic subjects.Ravi C. Bakaraju1, Klaus Ehrmann1, Arthur Ho, Eric B. Papas.(2008) Pantoscopic tilt in spectacle-corrected myopia and its effect on peripheral refraction. (FULL TEXT) Ophthalmic and Physiological Optics Volume 28, Issue 6, pages 538–549, November 2008
MyopiaPrevention.org comment: Glasses are commonly fit with a pantascopic tilt (bottom of lens tilted towards the face) of about 15 degrees. In this computer study, lenses of various powers were studied to see what happened to the peripheral power with various amounts of pantascopic tilt. Starting at around 6 Diopters in power, pantascopic tilt created a peripheral hyperopia of about 1.50 diopters. If peripheral hyperopia contributes to myopic development (as many believe), then pantascopic tilt contributes more to the problem.Daniel Adler, Michel Millodot.(2006) The possible effect of undercorrection on myopic progression in children. (FULL TEXT) Clinical and Experimental Optometry Vol. 89 Issue 5 September 2006 Pages 277–341 DOI: 10.1111/j.1444-0938.2006.00055.x
MyopiaPrevention.org comment: The author basically states that the results show that undercorrecton does not work as a preventive measure but it could not be shown that it actually makes things worse.Satoshi Hasebe, Chiaki Nakatsuka, Ichiro Hamasaki and Hiroshi Ohtsuki. (2005) Downward deviation of progressive addition lenses in a myopia control trial. (ABSTRACT) Ophthalmol Physiol Opt 25: 310-4.
MyopiaPrevention.org comment: Progressive Addition Lenses (PALs) used in children were found to be worn lower on the face than prescribed so that their effectiveness in any potential myopia control was reduced 30% to 60% (if control requires the full add) depending on the angle of gaze.Jane E. Gwiazda, Leslie Hyman, Thomas T. Norton, Mohamed E. M. Hussein, Wendy Marsh-Tootle, Ruth Manny, Ying Wang, Donald Everett and the COMET Group.(2004) Accommodation and related risk factors associated with myopia progression and their interaction with treatment in COMET children. (FULL TEXT) Invest Ophthalmol Vis Sci. 45: 2143-2151
MyopiaPrevention.org comment: Progressive Addition Lenses (PALs) in the COMET trial helped a subset of students the most, specifically those with a larger lag of accommodation and near esophoria. For this group of patients, the progression rate was 56% over three years. "The results support the COMET rationale (i.e., a role for retinal defocus in myopia progression). In clinical practice in the United States children with large lags of accommodation and near esophoria often are prescribed PALs or bifocals to improve visual performance. Results of this study suggest that such children, if myopic, may have an additional benefit of slowed progression of myopia."Jane Gwiazda, Leslie Hyman, Mohamed Hussein, Donald Everett, Thomas T. Norton, Daniel Kurtz, M. Cristina Leske, Ruth Manny, Wendy Marsh-Tootle, Mitch Scheiman, and the COMET Group (2003). A randomized clinical trial of progressive addition lenses versus single vision lenses on the progression of myopia in children. (FULL TEXT) Invest Ophthalmol Vis Sci. 44: 1492-500.
MyopiaPrevention.org comment: These are the results of the COMET study (Correction of Myopia Evaluation Trial). Progressive Addition Lenses (PALs) reduced the progression of myopia over a three year period by .20 diopters compared to a control group wearing single vision lenses. The effect was mostly in the first year and was greater for those with lower baseline levels of both myopia and accommodative response. All PALs had +2.00 adds. The control group progressed -1.48 diopters (100%) and the PAL group progressed -1.28 diopters (86%), a difference not considered clinically significant, especially since after the first year the lenses did not perform any better than the single vision lenses. PALs don't work very well if given to everyone.Zhu X, Winawer JA, Wallman J. (2003) Potency of myopic defocus in spectacle lens compensation. (FULL TEXT) Invest Ophthalmol Vis Sci. 2003 Jul;44(7):2818-27.
MyopiaPrevention.org comment: While it had been shown that plus lenses can slow elongation of the eye, indicating they were able to slow development of myopia, this study showed that as little as 12 minutes per day of plus lens wear in the chick eye were able to overcome daylong wearing of minus lenses. If children are like chicks in this respect, then long periods of hyperopic defocus during the day might be compensated for by brief periods of peripheral myopia created by plus lens blur.Chung K, Mohidin N, O'Leary DJ (2002). Undercorrection of myopia enhances rather than inhibits myopia progression. (ABSTRACT) Vision Res. 42: 2555-9
MyopiaPrevention.org comment: Undercorrection by approximately .75 diopters of 47 subjects over two years produced more rapid myopic progression. Undercorrection is commonly either requested by patients in the belief that it will help slow the process of myopia progression or is recommended by the doctor. This study refutes that common belief.Fulk, George W. PhD, OD, FAAO; Cyert, Lynn A. PhD, OD, FAAO; Parker, Donald E. PhD (2000) A Randomized Trial of the Effect of Single-Vision vs. Bifocal Lenses on Myopia Progression in Children with Esophoria (FULL TEXT) Optometry and Vision Science August 2000 - Volume 77 - Issue 8 - pp 395-401
MyopiaPrevention.org comment: Bifocal glasses with a +1.50 add slowed myopic progression by .25 diopters over 30 months compared to regular glasses, an amount considered slightly better than chance but not a strong enough effect to recommend the treatment. Leonard Press disputes the methodology in a future article where he states that "plus lens acceptance" should have been the criteria for amount of add provided in order to not negate the benefit of the add and that less, not more, add may be the necessary lens for myopia control) Optometry and Vision Science: December 2000 - Volume 77 - Issue 12 - pp 630-631 (FULL TEXT) , and the author responds in the same issue.Leung JT, Brown B (1999). Progression of myopia in Hong Kong Chinese schoolchildren is slowed by wearing progressive lenses. (ABSTRACT - Link for FULL TEXT pdf) Optom Vis Sci. 76: 346-54.
MyopiaPrevention.org comment: A two year study of approximately 68 students wearing single vision lenses, one group wearing +1.50 progressive addition lenses (PALs) and one wearing +2.00 PALs. The higher add group progressed the least, the lower add an intermediate amount and the single vision lens group progressed the most. This study showed a greater effect for PALs than other studies. There is a discussion of possible causes.McBRIEN, NEVILLE A.; GENTLE, ALEX; COTTRIALL, CHARLES. (1999) Optical Correction of Induced Axial Myopia in the Tree Shrew: Implications for Emmetropization. (ABSTRACT with link to full pdf) Optometry & Vision Science: June 1999 - Volume 76 - Issue 6
MyopiaPrevention.org comment: Emmetropization was shown to be driven by the clarity of the image on the retina, not by "a mechanism sensitive to abnormal eye shape." A more interesting study than it first appears. Myopia was induced by monocular deprivation (a well used experimental technique) and then the myopia was either fully corrected or left uncorrected. These were young tree shrews, not yet expected to have reached full emmetropization. When the induced mypopia (nearly 7 diopters) was fully corrected, the eye was prevented from recovering from the induced myopia. The uncorrected eyes were able to continue the emmetropization process to end up with a nearly non-myopic eye. "The results of the present study imply that the normal emmetropizaton process may be disrupted by correction of refractive error, particularly at an early age." MyopiaPrevention.org comment: In other words, giving glasses to a young myope may prevent their eyes from correcting themselves. The question remains identifying when is "young" and how to balance this possibility with the need for clear vision for tasks such as school.O Pärssinen, E Hemminki and A Klemetti(1989) Effect of spectacle use and accommodation on myopic progression: final results of a three-year randomised clinical trial among schoolchildren. (ABSTRACT) Br J Ophthalmol 1989;73:547-551
MyopiaPrevention.org comment: Three groups were studied: minus lenses with full correction for full time wear, minus lenses with full correction removed for reading and bifocals with a +1.75 add. All three groups progressed at about the same rate. More close work was associated with greater myopic progression for all three groups.Karla Zadnik, Donald O. Mutti, Nina E. Friedman, Pamela A. Qualley, Lisa A. Jones, Pei–hua Qiu, H. S. Kim, Jason C. Hsu and Melvin L. Moeschberger.(1999) Ocular predictors of the onset of juvenile myopia. (FULL TEXT) Invest Ophthalmol Vis Sci. 1999;40:1936–1943
MyopiaPrevention.org comment: Hyperopia measured by cycloplegic refraction in the third grade of less than +.75 predicted future myopia with a sensitivity of 86.7% and specificity of 73.3%. This means, if the data holds up, that the screening will detect approximately 87% of future myopes, but a quarter (100%-73.3%=26.7%)of those who don't go on to develop myopia will also be flagged as future myopes. The results were deemed not yet useful for clinical decisions but useful for future lines of research. (Morgan (2009) found later that children with low hyperopia were considered at risk for becoming myopic.)Wildsoet CF. (1997) Active emmetropization: evidence for its existence and ramifications for clinical practice. (ABSTRACT) Ophthalmic Physiol Opt. 1997 Jul;17(4):279-90
MyopiaPrevention.org comment: Quoting from the abstract: "Extrapolation of these findings to humans predicts ... that refractive correction of myopia will lead to accelerated progression. This convincing evidence for active emmetropization warrants due consideration in developing clinical management strategies for refractive errors." In other words, glasses for myopia may make myopia progress faster.