Ophthalmologists and optometrists are the vision specialists in North America. They are responsible for assessing vision and ability to focus on and discern objects. As well, they are responsible for the assessment and treatment of ocular pathologies. By assessing the eyes, it is possible to detect systemic diseases and signs of tumors in the brain.
Here is the overview of the eye examination:
– External examination;
– Visual acuity;
– Pupil function;
– Extraocular muscle motility;
– Visual fields;
– Intraocular pressure;
Some of these specific tests results can be influenced by the status of the tonic postural system.
Here is a discussion of a few of the tests that are influenced by the postural system and how this takes place.
Visual acuity and refraction:
Visual acuity is the eye’s ability to detect fine details and is the quantitative measure of the eye’s ability to see an in-focus image at a certain distance.
For example, a subject presenting with 20/20 vision can see at 20 feet what a normal person can see at 20 feet. A Snellen chart is typically used for this test.
A refractive error is an optical abnormality of the eye in which a corrective lens is needed for proper focusing. A refractive error is an optical defect that does not allow light to be brought into sharp focus on your retina. Examples of refractive error are myopia, hyperopia, and astigmatism.
It is important to mention that, as long at the target you are looking at is at 90 centimeters of further away from your eyes, vision is quite passive. In this scenario, it is the cornea that is mainly responsible for refraction. From 90 centimeters in, there is an important muscular component for the image to land on the retina.
Posturology has the potential of helping quite a bit with near vision (90 centimeters in). Since Posturology optimizes muscle function, the extra ocular muscles are no exception to that rule.
Ocular convergence, performed by the extra ocular muscles, is a criterion to performing well on vision tests 90 centimeters in. This happens to impact reading small print in the context of reading a textbook or reading off a computer screen.
Difficulty in performing these specific tasks can be a sign of poor coordination of eye movement, which also creates and reacts to a postural imbalance.
If your feet are misaligned, to keep your gaze on the horizon, you have to tilt the head. This happens involuntarily. Once the head is tilted, the tension of the neck muscles is asymmetrical. The neck muscles project to the eye muscles. And there you have it, an ocular convergence deficiency. In plain English, your eyes do not move together… your ability to see clearly within 90 centimeters is compromised.
On the other hand, let’s say you suffered even a mild cranial trauma at birth. It is not rare to see that, because of this, eyes are rarely leveled on a new born. As such, the length-tension relationship of the 12 extra ocular muscles (6 per eye) is compromised and ocular convergence cannot be synergetic. This, in turn, via the vestibular system, causes a head tilt and changes postural strategies. We compensate. Symptoms typically appear later.
2 other muscular phenomena occur to permit proper near sighted vision:
– Accomodation of the lens;
– Pupillary constriction.
The lens accommodates to allow an image to be projected to the retina, as it gets closer to us. It is a muscular phenomenon that is involuntary, mediated by the parasympathetic nervous system.
The iris performs constriction of the pupil. The constrictor muscle reacts to light and contracts to allow clarity of image on the retina. Its contraction is mediated by the parasympathetic nervous system.
The lens and iris share a common denominator: both innervated by the otic ganglion of the parasympathetic nervous system.
Poor posture and our hard headedness in wanting to stand on two feet, no matter what, contribute to stress in the body. This stress manifests itself by stimulating the sympathetic branch of the autonomic nervous system, decreasing the efficiency of the parasympathetic ganglia to perform their duties to the fullest.
Moral of the story:
Posturology can be a major contribution to optimizing the function of the visual apparatus that is motor, whether that motor component is under dependence of the somatic or autonomic nervous system.
Before the ophthalmologist or optometrist performs an eye examination for you, your best bet to get an accurate reading it to go in fully recalibrated. The best treatment is the most precise treatment. In that sense, Posturology and ophthalmology make a very good mix!