title: Retrospective, longitudinal, and cross sectional study of visual acuity impairment in choroideraemia.
abstract: OBJECTIVE
  Few studies have reported on the change in visual acuity (VA) in patients with choroideraemia. In order to determine the degree and rate of VA impairment associated with this disease, the central VA was analysed in a large group of patients with choroideraemia.
  
  
  METHODS
  The authors completed a retrospective, cross sectional review of 115 patients with choroideraemia from three tertiary care centres. A longitudinal analysis was performed on 45 of these patients who met the inclusion criteria of at least three visits over a minimum period of 4.5 years. Multiple linear regression analysis was used to explore the 5 year rate of VA change while controlling for initial VA and initial age. Multiple logistic regression was also used to investigate VA impairment.
  
  
  RESULTS
  In the cross sectional group (n = 115), 84% (87/103) of patients under the age of 60 had a VA of 20/40 or better while 33% (4/12) of patients 60 years of age or older had a VA of 20/200 or worse at their most recent visit. The majority of the patients (93%) in the longitudinal subgroup of 45 patients had a VA of 20/30 or better at their initial visit. The mean 5 year rate of VA change was 0.09 logMAR equivalent (approximately one line on the Lighthouse chart).
  
  
  CONCLUSIONS
  In this cohort of patients with choroideraemia, there was typically a slow rate of VA loss and the prognosis for central VA retention was, as a group, favourable until the seventh decade.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, 60612, USA.
authors.forename: M Flynn
authors.initials: MF
authors.lastname: Roberts
authors.forename: G A
authors.initials: GA
authors.lastname: Fishman
authors.forename: D K
authors.initials: DK
authors.lastname: Roberts
authors.forename: J R
authors.initials: JR
authors.lastname: Heckenlively
authors.forename: R G
authors.initials: RG
authors.lastname: Weleber
authors.forename: R J
authors.initials: RJ
authors.lastname: Anderson
authors.forename: S
authors.initials: S
authors.lastname: Grover
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D015794:Choroideremia / Q000150:complications / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D018450:Disease Progression; D006801:Humans; D016014:Linear Models; D008137:Longitudinal Studies; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D014786:Vision Disorders / Q000209:etiology* / Q000503:physiopathology; D014792:Visual Acuity