Could patients throw away their spectacles? Target refraction in both study groups was achieved by the six-month follow-up point and remained stable. In the first group,
with initially small accommodative amplitudes, low myopia was reached, whereas in the second group, emmetropic refraction
was achieved. In the control group of "young hyperopes", the initial refractive effect was higher but its regression was quicker
during the first three months, in comparison to the study groups. The mean preoperative spherical equivalent of refraction of patients in the first study group was +2.16±0.97 D. At one week
follow-up it was -3.30±0.73 D, at month one it was 2.66±0.67 D, at six months follow-up it was -1.66±0.58 D and by three years
it was -1.29±0.17. Mean preoperative spherical equivalent of refraction of patients in the second study group was +2.26±0.81D. By one week follow-up
it was -1.86±0.48 D, at one month follow-up it was -1.26±0.47 D, at six months follow-up it was -0.18±0.11 D and by three
years it was +0.20±0.18 D. In the first study group, we found that the perifocal oedema of the cornea surrounding coagulates was more pronounced than
in the second study group, corresponding to the higher energy level used. The decrease in perifocal corneal oedema occurred
simultaneously with the regression of the refractive effect of LTK. Corneal pachymetry during the early postoperative period revealed pronounced thickening of the cornea. In the first study
group, corneal thickness increased by 24.8% (597±17 μm at baseline to 745±39 μm at one week) and in the second study group,
corneal thickness increased by 18.5% (611±20 μm at baseline to 724±33 μm at one week). By three-months follow-up, corneal
thickness had returned to preoperative levels in both groups. In the "young hyperopes" control group the corneal thickness increase was higher (a 39.7% increase in thickness from baseline;
590±17 μm at baseline to 824±54 μm at one week), than in the first study group, despite the similar laser energy used in both.
And at three years? 
Figure 3
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By the end of the three-year follow-up period, the mean uncorrected distance visual acuity of the first study group had returned
to a level similar to that recorded preoperatively (0.47 at baseline to 0.5 at three-years). However, the mean near visual
acuity had increased by almost five Snellen lines (Figure 3).
In the second study group, which had a higher initial mean accommodative amplitude, there was an increase in uncorrected distance
visual acuity (0.54 at baseline to 0.95 at three-year follow-up) and the optic power of the near correction was reduced.
Figure 4
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Preoperative contrast sensitivity in the two study groups was significantly reduced in comparison with the control groups
but, by three to six month follow-up, when refraction had stabilized, the contrast sensitivity was restored to preoperative
levels (Figure 4). Accommodative amplitude increased during the first week but had stabilized in both study groups by three months.
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