ABSTRACT
@#AIM: To observe the effect of orthokeratology on the positive relative accommodation of juvenile with myopia. <p>METHODS: Retrospective analysis of cases. All 122 cases(244 eyes)of juvenile with myopic from September 2016 to December 2017 in our hospital were analyzed. 63 cases were corrected by orthokeratology lens and 59 cases were corrected by glasses. data of the binocular positive relative accommodation before treatment and 6mo after treatment were compared between the two groups. <p>RESULTS:Before treatment, the average PRA value of the orthokeratology group(-0.83±0.23)D and the average PRA value of the glasses group(-0.77±0.24)D were no significant difference(<i>t</i>= -1.457, <i>P</i>>0.05). There was no significant difference between the two groups before treatment in eye axis(orthokeratology group 24.84±0.90mm, glasses group 24.78±0.86mm, <i>t</i>=0.550, <i>P</i>>0.05). PRA in the orthokeratology group -2.27±0.37D was significantly higher than that in the pre-treatment group -0.83±0.23D(<i>t</i>=37.070, <i>P</i><0.001). There was no significant difference in PRA -0.83±0.24D at the end of 6mo compared with that before treatment -0.77±0.24D,(<i>t</i>=1.565, <i>P</i>>0.05). After treatment, the PRA of orthokeratology group was better than that of glasses group, and the difference was statistically significant(<i>t</i>=-25.271, <i>P</i><0.001). The eye axis of the orthokeratology group 24.86 ±0.91mm was significantly higher than that of the control group 24.84±0.90mm(<i>t</i>=-2.453, <i>P</i><0.05)at the end of 6mo. The eye axis of the glasses group 24.97±0.86mm was significantly different from that before treatment 24.78±0.86mm(<i>t</i>=39.135, <i>P</i><0.001). There was no significant difference in the eye axis between the orthokeratology group and the glasses group after 6mo(<i>t</i>=-0.932,<i>P</i>>0.05). <p>CONCLUSION: The corrected visual acuity of juvenile myopia by orthokeratology was significantly higher than that by using glasses 6mo after treatment, but there was no significant difference between the two groups in eye axis during 6mo.
ABSTRACT
AlM: To research the characteristics of positive relative accommodation ( PRA) , negative relative accommodation (NRA) and PRA/NRA ratio in myopes. To analyze the relationship among PRA, NRA, PRA/NRA ratio, spherical equivalent degree, years and habbits of wearing glasses, myopia development, and pupil diameter.METHODS: Aretrospective study of ninety eyes in the 180 th Hospital of Quanzhou from August 2014 to December 2014. PRA, NRA and PRA/NRA ratio were compared among low, moderate, high myopes and emmetropes. The correlation were analyzed among PRA, NRA, PRA/NRA ratio, spherical equivalent degree, years and habbits of wearing glasses, myopia development and pupil diameter. PRA, NRA, PRA/NRA ratio, years and habbits of wearing glasses and pupil diameter were compared between progress group and non-progress group.RESULTS: ( 1 ) Without statistical differences in age, sex and intraocular pressure, PRA and PRA/NRA ratio of myopes were lower than emmetropes, while NRA was higher. (2) Without statistical differences in age, sex and intraocular pressure, PRA, PRA/NRA ratio and NRA had no statistical differences while years and habbits of wearing glasses had statistical differences among low, moderate, high myopes. ( 3 ) With longer years of wearing glasses, PRA, PRA/NRA ratio were larger and NRA, pupils were smaller. ( 4 ) Without statistical differences in age, diopter and intraocular pressure, one group which were not easy to deepen degree had more often-wear-glasses myopia patiens and longer years of wearing glasses, the other group which were easy to deepen degree had more seldom-wear-glasses myopia patiens and shorter years of wearing glasses.CONCLUSlON: PRA and PRA/NRA ratio of myopes were lower than emmetropes, while NRA was higher. No correlated relation was detected among PRA, NRA, PRA/NRA ratio, spherical equivalent degree and myopia development. lt suggests the onset and progress of myopia are related to many factors. Wearing-glass timely and accurately can release the decline of PRA and PRA/NRA ratio and slow down degree development in myopes.