VT Works

An interesting part of Wachs Mental Minus is the manner in which it addresses all aspects of accommodation, from the stamina and flexibility of the mechanism, to the feeling tone attached to each position, to the awareness of the spatial changes we make in learning to accurately accommodate – it is all there.

Please note, in no way is there a suggestion of surprise in my commentary; more like admiration. Dr. Harry Wachs was a master when it came to human development of the visual system, and although he claimed to only have “two years and eight months” more education than non-optometrists, his understanding of what was needed to develop an efficient and finely tuned visual system was that of pure brilliance. The mark he left on Developmental Optometry is simply indelible.

Level Four – Clear and Blur at Will

Prior to my saunter into presbyopia, this was, by far, the toughest level to demonstrate to patients. Struggling with Accommodative Flexibility in my youth, I came to understand the meaning of visual stamina challenges first hand. The mechanisms and muscles at play here are so small, and yet it was not lost on me how much weight they must carry throughout our day.

Our setup for Level Four is the same as the previous levels – comfortably seated, Harmon’s distance, translucent patch, age appropriate sized font.

The initial instructional set includes placing the lens in front of the non-occluded eye and ask the patient to make the target clear. Hopefully, but this level of Mental Minus, both you and your patient are comfortable with choosing an appropriate power of lens for they can find success with some degree of effort. Unlike in previous levels, though, the patient is not going to remove the lens during this activity; instead, they should be asked to “let go” of their accommodation so the target becomes blurry again. When fully blurry, instruct the patient to clear the target. Rinse, lather, and repeat. The idea is to move accommodation from relaxation to stimulation repeatedly at will. An explanation that has offered me relative success with patients is to visualize a rubber band being repeatedly stretched to its limits and then slowly released, over and over again. This strength and stamina which is build up by repeated stimulation and relaxation of accommodation is what we are after.

For the Vision Therapist, observations might include constriction and relaxation of the pupil with relative fluidity, the occluded eye should be moving relative to the accommodative demand (stimulation of accommodation results in convergence and/or relaxation of accommodation results in divergence), and any mention of the SILO effects associated with the lens. In terms of discussion with the patient, this tends to be the level of Wachs Mental Minus where patients really discover feeling tone relative to where their accommodation is postured, so having that discussion seems to hold value, as well. As always, we want to repeat the activity with the other eye to ensure responses are equal.

From a purely subjective standpoint based on nothing more than my own experience with patients in the therapy room, this level tends to be such that patients need more time to feel successful. My sense is that all previous levels require reasonable effort to complete but their needed output seems to come in short bursts; conversely, this level requires effort over a sustained period of time making it a bit more intense for some, and requiring a more sustained level of control and strength than previous levels for most.

Not to be lost here is the need to build the patient’s awareness of what their eyes are doing. Questions like “do you feel your eyes changing?”, “what do your eyes feel like when you clear the lens versus letting things get blurry?”, and “does clearing this lens feel like anything else you have ever done with your eyes?”.

Remember, bringing a patient’s awareness to what they are doing and how they are doing it is key to their success. This level of understanding will help them to be successful with the activity, but more importantly, help them to take their newly discovered visual skills out into the real world as they find success.

Stay Tuned for Level Five – Clear Lens – Remove Lens and Keep Blurred