title: [Early visual results and mechanism of pseudo-accommodation of the Quatrix aspheric intraocular lens].
abstract: OBJECTIVE
  To assess the clinical and visual outcomes of the implantation of the Quatrix intraocular lens (IOL) and investigate the mechanism of pseudo-accommodation of these lens.
  
  
  METHODS
  Patients (67 eyes )received cataract surgery were offered the Quatrix IOL (32 eyes) and AR40e IOL (35 eyes). The patients' refractive status, uncorrected and best corrected distance visual acuities were assessed preoperatively, 1 week, 1 month and 3 months after surgery. Using the Ray-tracing method, the root mean square (RMS) values of the higher order aberrations for each subject with pupil diameters of 4.0 mm under accommodative stimuli were calculated.
  
  
  RESULTS
  The mean uncorrected distance visual acuity improved significantly from 0.70 to 0.22 logMAR by the end of 3 months postoperative for the Quatrix group. The mean uncorrected near acuity was statistically significantly higher in the Quatrix group than in the AR40e group at the 6 months post-operative examination. The internal spherical aberration increased and changed from a positive to a negative value with increasing accommodation at 4.0 mm of pupil diameter under accommodative stimuli for the Quatrix group. The total and internal high order aberrations had no significant difference after surgery in the control group.
  
  
  CONCLUSIONS
  Results show that the Quatix IOL is safe, effective, and stable. It provided some degree of pseudo-accommodation. Flexure changes to the optics of the Quatrix IOL during accommodation could explain some of the pseudo-accommodation of this IOL.
authors.affiliation: Tianjin Medical University, Tianjin, China.
authors.forename: Xiao-jie
authors.initials: XJ
authors.lastname: Xing
authors.forename: Xin
authors.initials: X
authors.lastname: Tang
authors.forename: Hui
authors.initials: H
authors.lastname: Song
mesh_terms: D000065:Accommodation, Ocular; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002386:Cataract / Q000628:therapy*; D015350:Contrast Sensitivity; D005260:Female; D006801:Humans; D019654:Lens Implantation, Intraocular / Q000379:methods*; D007910:Lenses, Intraocular; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D016896:Treatment Outcome