Miopía

¿Cómo prevenir la miopía?

Por un lado, para prevenir su aparición o progresión en la juventud, se recomienda pasar más tiempo en la calle, no necesariamente con actividad física [1, 6, 10, 11]. Se recomiendan:

1. Al menos 30 min / día a 10000 lux, incrementando el tiempo si la intensidad de la luz es menor [10].
2. Idealmente, 60 - 120 min / día en la calle [11].
3. Menos horas mirando smartphones, mejor [1].

Lux y lumen no son lo mismo. Lux: luz recibida por un objeto. Lúmen: luz emitida por una fuente de luz, en cualquier dirección y que puede no ser recibida por el objeto.

Se ha llegado a ver que una exposición de 6 h / día a 25000 lux llega a generar hipermetropía en animales, lo contrario a miopía [11].

Por otro lado, para prevenir la aparición o progresión durante la edad adulta, se sugiere una dieta variada rica en fitoquímicos, como la resultante de vivir comiendo plantas silvestres [14].

Un índice de masa corporal por debajo de 23Kg/m2 se asocia a menor riesgo de miopía [20].

¿Cómo frenar la miopía?

Además de lo anterior, se recomienda usar gafas que no bloqueen el paso de luz violeta, tanto en adultos, como en niños [16, 17].

No se recomienda el uso de gafas graduadas con tan solo una corrección parcial de la miopía, pero no está claro [19].

¿Cómo corregir la miopía con ejercicio?

La miopía es un error de refracción que empeora la agudeza visual [7]. El error de refracción se puede corregir o compensar con gafas, lentillas, medicamentos o cirugía. La agudeza visual, lo que en definitiva somos capaces de ver, también se puede mejorar con ejercicios correctivos [1], ya que no sólo depende de la refracción. 

Ejercicios que sí parecen funcionar: [13, ¿8?].

Los ejercicios tradicionales chinos basados en masaje podrían prevenir o ralentizar ligeramente la progresión de la miopía en jóvenes [2, 4]. La obligación de practicarlos en las escuelas chinas no parece surtir el efecto deseado, quizás por una mala ejecución [2, 3, 4].

Bates eye exercise therapy y Trataka Yoga Kriya parecen no ser efectivos mejorando la agudeza visual [12].

¿Cómo medir la miopía?

Parece ser más recomendable graduar la vista viendo objetos en movimiento, no estáticos, como es habitual [18].

#ideas

Myopia is thought to be a multi-factorial disorder with hereditary and environmental variables interacting to cause the condition's rapid rise in prevalence. Environmental factors that affect the progression of myopia include things like education and urbanization, time spent outside, light wavelength, and physical activity.

Proponen gafas de realidad virtual para ejercitar los ojos de forma óptima.

 [9]

 

Myopia can be divided into simple myopia and pathological myopia. The most common one in adolescents is the simple myopia, which is induced by a combination of genetic and environmental factors, and is related to the weakening of visual regulation caused by spasm of the extraocular and ciliary muscles, which will gradually lead to the growth of the eye axis if it is not restored in time. Therefore, the functions of the extraocular and ciliary muscles are crucial for maintaining good vision. If not corrected in time, myopia will lead to serious and irreversible complications such as retinal detachment, macular degeneration, glaucoma, and blindness. Strengthening vision protection for adolescents has become an urgent issue that needs to be addressed.

The earliest and most widely known is the Bates Vision Acuity Training Method, including eye sunbathing, palm massage, rope games, ruler games, pencil games, etc. But due to the complexity of its training, long cycles, etc., it has not been widely promoted. At present, the common vision training mainly relieves the ciliary muscle tension by repeatedly focusing on the distant visual target, looking at the distance and movement of the image to adjust the function of the extraocular muscles, and through the different light color changes to stimulate the visual cortex, as ways to improve vision and restore to a good visual system.

Training based on guided meditation for vision acuity:

1. Abdominal breathing: Inhale through the nose, exhale through the mouth, bulge abdomen while inhaling, tighten abdomen while exhaling; start doing abdominal breathing when hearing the words of “adjust your breath and inhale.”

2. Eye-warning exercise: Rub your hands more than 30 times, cover your eyes with the palms, place thumbs on the temples, clasp four fingers on your forehead, and leverage the temperature of your palms to warm eyes; after the temperature gradually dissipates, use Yuji acupoints of the palms to gently press your eyes 5 times, with moderate intensity; start eye-warning exercise when you hear the words “get ready to press” and “quickly rub your hands” during training.

3. Healthy vision exercise: Press both hand palms on your ears, place fingers on the back of your head; do not move the palms, and use fingers to gently tap the back of your head. During the training, when you hear “healthy vision exercise,” start doing it.

4. Activate Shixuan acupuncture point: Tap your fingers on your palm, shake your palm, and make an arrow shape.

5. Play the “1-Audio,” turn off the lights in the classroom, close the curtains, and try to create a dark environment. Remain quiet the entire time. Close your eyes until the audio says to open them. Follow the audio to imagine and do movements, e.g., “Use the fingertips of one hand to gently touch the center of the palm of the other, and then shake your hand vigorously.”

6. Play the “C-video,” a video about lotus flowers to stimulate the imagination and match the 2-Audio with the images that appear in the video. For example, “On a calm lake, you can definitely see the vivid color of the lotus flowers and the greenish-blue leaves of the lotus .......”

7. Demonstration and correction. Make a hollow bowl shape with your hands (thumbs on the second knuckle of your index finger) and clasp them over your eyes, with palms facing your eyes.

8. Play “2-Audio” and do the eye stretches: Close your eyes and move them from front to back as if a train is moving back and forth in a tunnel.

9. Play “3-Audio” and listen to the audio with your hands in a hollow bowl shape over your eyes the whole time. When the audio says “in,” put pressure on your eyes for 1 s, and when it says “out,” relax your eyes and perform the related imagery and actions. When the audio says “pull” in future exercises, let your eyes enter a state just like going into a tunnel, hold for 1 s, and then relax.

10. Play “D-Video (Ball of Light)” to stimulate imagination and introduce natural light.

11. Play “4-Audio” to build up the confidence of myopia sufferers to restore their eyesight.

12. The above training will be repeated on the 8th day to intensify the effect, for 1 h.

Daily vision acuity training

Guided by the second set of audio and video movement verbal commands, the subjects perform self-rehabilitation exercises.

1. Ocular exercises: keep body and head still, torso upright, move only eyes, four 8-tempos per part:

1.1. both eyes look up and down to the left.

1.2. both eyes look up and down to the right.

1.3. both eyes look to the left to the right. 

1.4. both eyes turn clockwise.

1.5. turn both eyes counterclockwise.

1.6. close your eyes hard and then open them to look up.

1.7. close your eyes for a moment to control the time. 

2. Eye-warming exercises: same movements as before, 12 movements per day.

3. Vision acuity exercise: same movements as before, 24 movements per day.

4. Character card stretching: 10 min of training, with results recorded on an observation chart. Character cards (Chinese characters of different sizes) are placed on a well-lit wall at the subject’s eye level. Find the farthest place where you can see the card clearly, that is, about 10–15 cm back where you cannot see the card clearly. Let your eyes stretch 6 times for 1.5 s each (eye movement, stretching backwards), without blinking, stare at the characters for 10 s, step back 15 cm, and repeat the above movements until you are unable to see the location of the character card after stretching. If the training time is less than 10 min, switch to a second character and repeat the above steps; if it has reached 10 min, end the exercise and take notes.

[8]

 

These eye exercises not only focus on external ocular muscles but also on internal weak muscles.

The first exercise was eye muscle relaxation exercise which aims to warm up and stretch out the EOMs
(external ocular muscles) by asking the patients to close their eyes for 10 minutes and then focus on a
certain point in front.

The second exercise aimed at EOMs strengthening, patients were asked to focus their eyes on the tip of the therapist’s finger while opening the eyes as wide as possible. Then, patients were allowed to rest their eyes for a few minutes.

The third exercise aimed at correcting the shape of the cornea by asking the patients to open their eyes widely and to track the therapist’s finger by moving their eyes only with a fixed head position for 20 seconds and then return to the primary position of vision, this exercise was repeated 10 times.

8meses, varias veces al día (sin definir), mejoras de hasta -1,5 dioptrías en adultos 15-30años. Mejora la agudeza visual, no el error de refracción. Cuanto más jóvenes más efectivo. Go early to sleep.

[1]

traditional Chinese massage therapy and are performed in the form of self-massage of acupoints around the eyes.

Chinese eye exercises have a modest protective effect on myopic control, but considering that the incorrect performance of and attitude toward eye exercises have a significant influence on the effect of eye exercises, the effect of eye exercises may not be enough to prevent the progress of myopia in the long term, and more standardized eye exercises need to be conducted.

 [2]

 

In China, compulsory eye exercises for schoolchildren, to be performed twice a day during school days.

Eye exercises are not effective in preventing or controlling the progression of myopia in children.

 

[3] 

It has been shown that increased UVB exposure in children and adolescents is associated with regression of myopia, especially during the puberty period. 

the level of vitamin D can be used only as a marker of exposure to the external environment, which is an actual protective factor against myopia 

it can be concluded that in the case of no environmental risk factors, myopia will not develop, even with genetic load

In addition, other studies have shown that children who read a lot get higher scores in IQ tests and are more prone to myopia, because they tend to do more near work. On the other hand, the researchers revealed a statistically significant correlation between the occurrence of myopia in children and higher education of their parents.

poor effect: contact lenses, bifocal and multifocal spectacle lenses, and pinhole glasses.

modern orthokeratology methods podrían tener mayor efecto, asumiendo algunos riesgos.

Due to the continuity along the superficial fascia and the tendinous galea, tension can be transferred from the trunk to the eyeball. There is a similar continuity along the superficial fascia of the chest and the platysma, which is connected with the superficial muscular aponeurotic system (SMAS) comprising the mimical muscles of the face.

Osteopathic techniques applied to cranial areas can have a positive effect on the visual function in young adults with myopia 

[4]

Failure to correct or under-correction of myopia hastens its progression. Effective treatments for myopia include spectacles (glasses), soft contact lenses, orthokeratology (rigid contact lenses that land on the sclera, or white of the eye, and are worn at night to reshape the cornea), and low-dose atropine eyedrops. Randomized trials suggest that low-level red light shined into the eye twice a day may also slow myopia progression [15].

Palabras clave

Visual acuity.

Referencias

1. 2020: SHAREEF, Hassnaa; SAMEEN, Munther; JAFAAR, Shaimaa. The Impact of Eye Exercises on High Myopia and Visual Acuity in Patients Aged (15-30) Years. En Journal of Physics: Conference Series. IOP Publishing, 2020. p. 012108. 

2. 2023 systematic review and meta-analysis: TANG, Jie, et al. The association between Chinese eye exercises and myopia in children and adolescents: A systematic review and meta-analysis. Frontiers in Public Health, 2023, vol. 11, p. 950700.

3. 2023 systematic review and meta-analysis: LIN, Zhicheng; XIAO, Feng; CHENG, Weiye. Eye Exercises for Myopia Prevention and Control: A Systemic Review and Meta-Analysis. medRxiv, 2023, p. 2023.01. 29.23284986. 

4. 2018: ZORENA, Katarzyna, et al. Early intervention and nonpharmacological therapy of myopia in young adults. Journal of ophthalmology, 2018, vol. 2018.

5. 2009: ALLEN, Peter M., et al. Aberration control and vision training as an effective means of improving accommodation in individuals with myopia. Investigative ophthalmology & visual science, 2009, vol. 50, no 11, p. 5120-5129.

6. 2017, systematic review: SUHR THYKJAER, Anne; LUNDBERG, Kristian; GRAUSLUND, Jakob. Physical activity in relation to development and progression of myopia–a systematic review. Acta Ophthalmologica, 2017, vol. 95, no 7, p. 651-659. 

7. 2021: KLEINSTEIN, Robert N., et al. Uncorrected Refractive Error and Distance Visual Acuity in Children Ages 6–14 Years. Optometry and vision science: official publication of the American Academy of Optometry, 2021, vol. 98, no 1, p. 3.

8. 2022, estudio en marcha: LI, Yibo, et al. Guided meditation for vision acuity training on adolescent myopia: study protocol for an open-label, prospective, multicenter, randomized controlled trial. Trials, 2022, vol. 23, no 1, p. 16.

9. 2023: ALI, Saba Ghazanfar, et al. A systematic review: Virtual-reality-based techniques for human exercises and health improvement. Frontiers in Public Health, 2023, vol. 11, p. 1143947. 

10. 2018: WU, Pei-Chang, et al. Myopia prevention and outdoor light intensity in a school-based cluster randomized trial. Ophthalmology, 2018, vol. 125, no 8, p. 1239-1250.

11. 2018: Dharani R (2018) Sunlight Does Explain the Protective Effect of Outdoor Activity Against Myopia. J Eye Dis Disord 3: 121. 

12. 2018: TIWARI, Komal Krishna, et al. A comparative study on the effects of vintage nonpharmacological techniques in reducing myopia (Bates eye exercise therapy vs. Trataka Yoga Kriya). International Journal of Yoga, 2018, vol. 11, no 1, p. 72.

13. 2016: Nitin Gosewade, Amol Drugkar, Vinod Shende. Effect of pranayama and eye exercises on visual acuity of medical students: a case control study. International Journal of Con- temporary Medical Research 2016;3(4):1133-1136.

14. 2015: LONDON, Douglas S.; BEEZHOLD, Bonnie. A phytochemical-rich diet may explain the absence of age-related decline in visual acuity of Amazonian hunter-gatherers in Ecuador. Nutrition Research, 2015, vol. 35, no 2, p. 107-117.

15. KRAMER, Michael S. I Can See Clearly Now: Do Glasses Make You More Nearsighted?. En Believe It or Not: The History, Culture, and Science Behind Health Beliefs and Practices. Cham: Springer Nature Switzerland, 2023. p. 79-87.

16. MORI, Kiwako, et al. Effect of violet light-transmitting eyeglasses on axial elongation in myopic children: a randomized controlled trial. Journal of clinical medicine, 2021, vol. 10, no 22, p. 5462.

17. ULLAH, Saif; UMER, Muhammad F.; CHANDRAN, Suriyakala P. Violet light transmission through eyeglasses and its effects on myopic children: A systematic review and meta-analysis. Saudi Journal of Ophthalmology, 2024, vol. 38, no 3, p. 235-242.

18. WANG, Yuexin, et al. Binocular dynamic visual acuity in eyeglass-corrected myopic patients. JoVE (Journal of Visualized Experiments), 2022, no 181, p. e63864.

19. YAZDANI, Negareh, et al. Under-correction or full correction of myopia? A meta-analysis. Journal of Optometry, 2021, vol. 14, no 1, p. 11-19.

20. QU, Yaohui; HUANG, Huamin; ZHANG, Hongxing. Association between body mass index and myopia in the United States population in the National Health and Nutrition Examination Surveys 1999 to 2008: a cross-sectional study. European Journal of Medical Research, 2023, vol. 28, no 1, p. 561.