Hello all,
I'm expecting an outside Rx today for a potential fitting for a Px self reporting Nystagmus (presumably horizontal.) I'd value the input of those here who have some experience with it. Also you engineering minded, please feel free to peruse my thinking and critique:
I use both pupilometer and PD stick for every patient (to catch those secretly converging in the widget.)
I've been advised the better results using a pupilometer is binocular; occlusion tends to exacerbate the motion of the single eye.
With the stick, it occurs to me gauging the outside boundary of the iris is particularly prone to parallax--and unlike other patients the curvature of the eye may play into the math correction if it's darting out far enough.
The null point seems an attractive place to establish a binocular value, which suggests to me the best place to measure is in normal position squared up bridge-to-bridge with the patient and do monocular parallax calculation for the outer eye if necessary.
I'm also told a NPD measurement is more stable, from which I can reverse engineer a DPD.
I'm tempted to try everything for the sake of data capture and hope I end up with a valid (or at least statistically favorable) answer after the fact. If y'all care to volunteer angles and techniques I can do while he's here, please feel free.
Would I be correct in inducing this Px historically favors executive BF for the sake of a wider seg that captures his gaze more reliably?
Edit to add: Just to be explicit--my thought is to gauge the edges of iris at the boundaries of horizontal motion--with the tentative assumption that the ideal PD placement is in the center of the values.
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