Changes In Amplitude Of Accommodation After LASIK And Its Relationship With Asthenopia

Objective:Laser corneal refractive surgery has been used to correct ametropic eyes for nearly 20 years in China. It helps millions of ametropic people to take their heavy spectacles off,especially for myopes. Especially nowadays, as people tend to efficient work and high quality life, it is also a kind of reliable choice for those fashion people wearing eyeglasses. On the other hand, some myopes with asthenopia symptoms during the early stage after the surgery, disturb their work and study, which should arouse our concern. The aim of the research is to investigate the influence for the ampltitude of accommodation and to discuss the relationship between postoperative accommodative amplitude and asthenopia in the early period after LASIK, to evaluate the clinic effect of LASIK.Methods:20 emmetropes and 60 myopes experienced LASIK from March 2009 to August 2009 aged 18-35 years old were selected form the ophthalmology department in the 2nd affiliated hospital of Dalian' Medical University. The myopes were divided into 2 groups:low and medium myopes with SE≤-6.00D (36cases 72 eyes) and high myopes with SE>-6.00D(24 cases 48 eyes);20 emmetropes(40eyes average age 25.34±5.37 years SE-0.50-+0.50, BCVA≥1.0) were selected as comparsion. Accomm-odative amplitudes for all people before surgery,1 week,2 week,1 month after surgery were surveyed,while symptoms of asthenopia were evaluated by questionnaire. Surgery was operated by one skilled surgeon. SPSS11.0 statistic software was used to analyze the data, P value less than 0.05 was considered significant.Results:1.Accommodative functions:The simple and both eye amplitude of accommodation descended at 1 week after LASIK, while recovered and surpassed the pre-operative level at 1 month after LASIK, and there was no significant difference between the myopes and emmetropes after 1 month.2.Symptoms of asthenopia:The asthenopia symptoms of myopes aggravated significantly during in the first week after LASIK, and recoverd at 1 month after LASIK.3.Correlation analysis showed that the symptoms of asthenopia has a negative correlation with accommodative amplitude in the first week after surgery. The descending extent of the accommodative amplitude has positively relation with the refractive power before surgery.Conclusion:1.After LASIK,the accommodative amplitude appears to decrease temporarily, especially in the first week after LASIK, and then recovered progressively.2.The symptoms of asthenopia after LASIK are associated with the change of accommodative amplitude.3. LASIK have no harmful effects on the accommodation amplitude.