title: Negative dysphotopsia: long-term study and possible explanation for transient symptoms.
abstract: OBJECTIVE
  To study the incidence, course, and common factors of patients with negative dysphotopsia and consider the possible role of the corneal incision in cases in which symptoms are transient.
  
  
  METHODS
  Private practice and the University of Cincinnati, College of Medicine, Cincinnati, Ohio, USA.
  
  
  METHODS
  Phacoemulsification with implantation of a single-piece acrylic intraocular lens (IOL) was performed in 250 consecutive routine cataract procedures. Patients were asked whether they noticed a temporal shadow on the day after surgery and were followed by serial evaluations for 3 years. Evaluations included subjective questionnaires and objective testing.
  
  
  RESULTS
  The incidence of negative dysphotopsia was 15.2% on the first postoperative day, decreasing to 3.2% after 1 year, then 2.4% after 2 and 3 years. Common findings included a shallow orbit, prominent globe, space greater than 0.45 mm between the iris and IOL by ultrasound biomicroscopy, and perimetric comet-shaped light in the area corresponding to the shadow. Slitlamp revealed a transparent peripheral capsule and a shadow sign in which a linear shadow on the iris became curvilinear as the light from the slit beam was projected through the incision toward the pupil.
  
  
  CONCLUSIONS
  Two groups of patients experienced negative dysphotopsia that rapidly resolved or remained unchanged from the first postoperative day. It is hypothesized that the corneal edema associated with a beveled temporal incision contributes to transient negative dysphotopsia.
authors.affiliation: University of Cincinnati, College of Medicine, Cincinnati, Ohio 45242, USA. rhosher@cincinnatieye.com
authors.forename: Robert H
authors.initials: RH
authors.lastname: Osher
mesh_terms: D000180:Acrylic Resins; D000368:Aged; D000869:Anterior Eye Segment / Q000000981:diagnostic imaging; D015715:Corneal Edema / Q000150:complications; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D019654:Lens Implantation, Intraocular; D007910:Lenses, Intraocular; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D018918:Phacoemulsification; D011795:Surveys and Questionnaires; D014786:Vision Disorders / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology; D014794:Visual Fields
chemical_list: D000180:Acrylic Resins