title: Color blindness among multiple sclerosis patients in Isfahan.
abstract: BACKGROUND
  Multiple sclerosis (MS) is a disease of young and middle aged individuals with a demyelinative axonal damage nature in central nervous system that causes various signs and symptoms. As color vision needs normal function of optic nerve and macula, it is proposed that MS can alter it via influencing optic nerve. In this survey, we evaluated color vision abnormalities and its relationship with history of optic neuritis and abnormal visual evoked potentials (VEPs) among MS patients.
  
  
  METHODS
  The case group was included of clinically definitive MS patients and the same number of normal population was enrolled as the control group. Color vision of all the participants was evaluated by Ishihara test and then visual evoked potential (VEPs) and history of optic neuritis (ON) was assessed among them. Then, frequency of color blindness was compared between the case and the control group. Finally, color blinded patients were compared to those with the history of ON and abnormal VEPs.
  
  
  RESULTS
  63 MS patients and the same number of normal populations were enrolled in this study. 12 patients had color blindness based on the Ishihara test; only 3 of them were among the control group, which showed a significant different between the two groups (P = 0.013). There was a significant relationship between the color blindness and abnormal VEP (R = 0.53, P = 0.023) but not for the color blindness and ON (P = 0.67).
  
  
  CONCLUSIONS
  This study demonstrates a significant correlation between color blindness and multiple sclerosis including ones with abnormal prolonged VEP latencies. Therefore, in individuals with acquired color vision impairment, an evaluation for potentially serious underlying diseases like MS is essential.
authors.affiliation: Department of Neurology, Isfahan Neuroscience Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Vahid
authors.initials: V
authors.lastname: Shaygannejad
authors.forename: Khodayar
authors.initials: K
authors.lastname: Golabchi
authors.forename: Alireza
authors.initials: A
authors.lastname: Dehghani
authors.forename: Fereshteh
authors.initials: F
authors.lastname: Ashtari
authors.forename: Sepehr
authors.initials: S
authors.lastname: Haghighi
authors.forename: Mahsa
authors.initials: M
authors.lastname: Mirzendehdel
authors.forename: Majid
authors.initials: M
authors.lastname: Ghasemi