Proposed order of ocular parameters change: trading vs reducing cylinder

WARNING: All those numbers are imaginary, not real! I hypothesize as MY eyes worked/work, YOUR may react better / improve faster using e.g. trading cylinder, so opposite to mine! There are sub-exact calculations, not meant to show all the perfect precision of math.

Trading cylinder

There is an increase in axial length for first or along with flattening of the cornea at more myopic / less hyperopic meridiansand steepening of less myopic / more hyperopic meridians.
It is followed by decrease in axial length and eliminating leftover directional positive (myopic) defocus.

Normal KER 43.25x43.75 D
Normal AL 23.30 mm, 1.00 mm = 3.00 D
Average improvement rate
Spherical 1 D/yr
Cylindrical 2 D/yr

Example:

  1. Initial parameters
    RX -1.50
    REF -0.75/-1.50x180
    SE -1.50
    KER 43.00x45.00, 0.5 compensated by crystalline lens
    AL 23.80 mm

  2. 3 months after
    RX -1.50
    REF -1.50/-1.50x180 (note: cylinder hasn’t changed!)
    SE -2.25
    KER 43.25x45.00 (my corneal power seemed to increase while using stronger lenses)
    AL 24.05 mm

  3. 6 months after
    RX -1.50
    REF -1.50/-0.50x180
    SE -1.75
    KER 43.00x44.00, 0.5 crystalline lens compensation
    AL 23.90 mm

  4. 9 months after
    RX -1.50
    REF -1.50
    SE -1.50
    KER 43.25x43.75, -0.50x90 lens astigmatism
    AL 23.80 mm

Reducing cylinder

It seem to do job faster than previous - there’s no need to increase then decrease AL, since there a negative (hyperopic) defocus is not present.

Normal KER, AL (…) are the same as with previous case.

Example:

  1. Initial parameters
    RX -0.75
    REF -0.75/-1.50x180
    SE -1.50
    KER 43.00x45.00 (look an explanation for less amount of real/refracted astigmatism in previous case)
    AL 23.80 mm

  2. 4.5 months after
    RX -0.75
    REF -0.75/-0.75x180
    SE -1.00
    KER 43.25x44.50
    AL 23.63 mm

  3. 9 months after
    RX -0.75
    REF -0.75
    SE -0.75
    KER 43.25x43.75
    AL 23.50 mm (now compare that to reducing cylinder by previous scheme)

steepening of less myopic / more hyperopic meridians

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