Macular thickness refers to the measurement of the thickness of the macula. The macula is the central part of the retina responsible for sharp, central vision. The retina, in turn, is the light-sensitive layer at the back of the eye. A normal macular thickness is essential for clear vision. Abnormalities in macular thickness, whether it’s too thick or too thin, can indicate various eye diseases or conditions. For instance, increased macular thickness can be seen in conditions like macular edema, while decreased thickness can be indicative of conditions such as age-related macular degeneration.
Intraocular pressure is the fluid pressure inside the eye. You might have had yours measured if you ever had one of those air-puff tests where a puff of air is blown against your eyeball. Intraocular pressure is measured in millimeters of mercury (mmHg). It is an essential parameter in evaluating eye health.
The study notes that exercise and movement has beneficial effects for eye health and be a factor to prevent or delay on some of the major causes of blindness, such as glaucoma, age-related macular degeneration, and diabetic retinopathy.
The 29 participants were guided by an experienced yoga. The session lasted 10 minuutes and consisted of a short relaxation technique, slow and continuous movements with stretching of the muscles of the eyes by moving them maximally horizontally, vertically, diagonally, and with clockwise and counter-clockwise circular movements. After the exercises, participants palmed their eyes (what the yogi on the image above is doing) after rubbing their palms together to warm them up. Participants were instructed to breathe deeply and slowly during the initial relaxation and between the various ocular exercises.
Immediately after the routine, the eyes were measured. Intraocular pressure decreased and macular thickness increased.
Because the yoga routine included breating and relaxation techniques, the study cannot is unable to state whether the pure muscular exercises led to the changes in intraocular pressure and macular thickness or whether it was the whole yoga routine. Stress is known to increase intraocular pressure. For example, one study2 showed that patients with glaucoma who practiced 45 min meditation daily for 6 weeks achieved a significant reduction in intraocular pressure and of various stress markers. They also improved brain oxygenation and quality of life.
Another shortcoming of the study is that it represents a snapshot in time. It would have been interesting to see the effect of daily practice over 4 weeks.
Nevertheless, I am convinced that we need to exercise our eyes the same as we have to exercise the rest of our body. Not only do the vast majority of us sit much too much, we also do not look enough into the distance. Using our eyes excessively for close distances is the ocular equivalent of sitting. We need to stretch and strengthen our eye muscles to combat the detrimental effects of excessive close-up viewing. Experts recommend looking into the distance for at least 20 seconds for every 20 minutes of close-up work. I’ve noticed that doing so helps maintain my distance vision.
I recently started eye exercises because I am noticing how my distance vision is deteriorating from extensive close-up work. I will report back in some months.
- Galina, Dimitrova et al. “Immediate Effect of Yoga Exercises for Eyes on the Macular Thickness.” International journal of yoga vol. 13,3 (2020): 223-226. ↩︎
- Gagrani, Meghal et al. “Meditation enhances brain oxygenation, upregulates BDNF and improves quality of life in patients with primary open angle glaucoma: A randomized controlled trial.” Restorative neurology and neuroscience vol. 36,6 (2018): 741-753. doi:10.3233/RNN-180857. ↩︎