title: Risk factors associated with night vision disturbances after phakic intraocular lens implantation.
abstract: OBJECTIVE
  To investigate the incidence and severity of night vision disturbances after implantable collamer lens surgery and to analyze the risk factors.
  
  
  METHODS
  Retrospective, noncomparative study.
  
  
  METHODS
  Medical charts from 50 eyes of 25 patients who underwent implantable collamer lens implantation were retrospectively reviewed. The incidence and severity of night vision disturbances were evaluated using questionnaires administered 6 months after surgery. Univariate simple and multiple logistic regression analyses were used to detect risk factors associated with postoperative night vision disturbances. Potential risk factors included in the analysis were keratometric value, anterior chamber depth, postoperative residual refractive error, higher-order aberrations, preoperative and postoperative mesopic pupil size, the difference between preoperative and postoperative mesopic pupil size, the difference between mesopic pupil size and implantable collamer lens optic zone diameter, white-to-white diameter, sulcus-to-sulcus diameter, and postoperative implantable collamer lens vaulting. The power, size, optic zone diameter, and toricity of the implantable collamer lens were also included as variables.
  
  
  RESULTS
  The incidence of night vision disturbances was 34.0% for halos and 26.0% for glare. Halos were found to be significantly related to the difference between mesopic pupil size and implantable collamer lens optic zone diameter (P = .013), white-to-white diameter of the cornea (P = .028), and implantable collamer lens optic zone diameter (P = .030). For glare, toricity of the implantable collamer lens was revealed as a significant risk factor (P = .047).
  
  
  CONCLUSIONS
  Although not severe, the incidence of night vision disturbances after implantable collamer lens implantation was not negligible. Possible risk factors for night vision disturbances include implantable collamer lens optic zone diameter, the difference between mesopic pupil size and implantable collamer lens optic zone diameter, and white-to-white diameter of the cornea for causing halos, and the toricity of the implantable collamer lens for causing glare.
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Dong Hui
authors.initials: DH
authors.lastname: Lim
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: In Jeong
authors.initials: IJ
authors.lastname: Lyu
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea; Happy Eye Clinic, Gwangju, South Korea.
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
authors.forename: Eui-Sang
authors.initials: ES
authors.lastname: Chung
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea. Electronic address: tychung@skku.edu.
authors.forename: Tae-Young
authors.initials: TY
authors.lastname: Chung
mesh_terms: D000328:Adult; D001251:Astigmatism / Q000601:surgery; D005260:Female; D019466:Glare; D006801:Humans; D015994:Incidence; D019654:Lens Implantation, Intraocular; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D009216:Myopia / Q000601:surgery; D009755:Night Blindness / Q000175:diagnosis / Q000453:epidemiology* / Q000209:etiology; D054120:Phakic Intraocular Lenses; D011183:Postoperative Complications; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D016896:Treatment Outcome; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult