An Initial Study Of Clinical Application Of LASIK Using Monovision And The Carl Zeiss Meditec MEL80 Shotfile Software To Correct Presbyopia (Report Of 4 Cases)

Objective To evaluate the short term clinical effect of LASIK for myopia and presbyopia using monovision and the Carl Zeiss Meditec MEL80 shotfile software.Methods Four myopic and presbyopic patients,43 years or older,who sought LASIK vision correction in the Eye Center of the Second Affiliated Hospital(Medical College, Zhejiang University) from January 2008 to October 2008 with a follow-up of 3 months were involved in this prospective study.The target refraction was plano for dominant eyes(distance eyes) and range -0.25 to -0.50 diopters(D) for non-dominant eyes(near eyes).Then the non-dominant eyes underwent the treatments of the Carl Zeiss Meditec MELS0 shotfile software.Distance and near uncorrected visual acuity,best spectacle-corrected visual acuity,spherical equivalent refraction,spherical aberration, contrast sensitivity,amplitude of accommodation preoperative and postoperative 1-week,1-month,3-months respectively were recorded.Results Operations were successful in all the cases without any complications.The distance uncorrected visual acuity(UCVA) was 1.0 in the dominant eyes and 0.8 or better in the non-dominant eyes after surgery,and the near vision of four patients improved in the non-dominant eyes.No eyes lost any line of best spectacle-corrected visual acuity(BSCVA).The postoperative spherical equivalent refraction was±0.50 D. The 4th spherical aberration decreased after the operation in the dominant eyes and increased in the non-dominant eyes(Malacara Notation).There was a general reduction in the contrast sensitivity in all spatial frequencies at postoperative 1-week when they were compared with the preoperative contrast sensitivity.By 1-month visit,all the eyes showed a recovery of the contrast sensitivity function with time going by and the contrast sensitivities at 6.3,4.0 deg spatial frequencies were better than that before the operation in the non-dominant eyes.So was the change of the binocular amplitude of accommodation.Conclusions LASIK for myopia and presbyopia using monovision and the Carl Zeiss Meditec MEL80 shotfile software is safe and effective.And it can provide better near vision by the maximal preservation of unaffected distance vision.