title: Correlation between optic nerve involvement and chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. The aim of this study was to evaluate the rate of optic neuropathy in COPD patients.
  
  
  METHODS
  Forty patients diagnosed with COPD and 60 healthy subjects as control group enrolled. After examination by a pulmonary subspecialist, patients were ranked by Global initiative for chronic Obstructive Lung Disease (GOLD) criteria, and patients with zero grades on GOLD criteria were excluded. Visual evoked potential by checkerboard (raster background) method with a frequency of 2 Hz were done for all participants. P-values less than 0.05 were considered as significant.
  
  
  RESULTS
  Fifty-five percent of COPD patients had visual evoked potential abnormalities. Mean P100 latency in both eyes was significantly longer in COPD patients. Average P100/N140 amplitude in both eyes were insignificantly higher in COPD.
  
  
  CONCLUSIONS
  Higher P100 latency in COPD patients shows demyelinating type of optic nerve involvement; however, further investigation in this area is needed.
authors.affiliation: Tuberculosis and Lung Diseases Research Center, Tabriz University of Medical Science, Tabriz, Iran.
authors.forename: Haleh
authors.initials: H
authors.lastname: Mikaeili
authors.affiliation: Neuroscience Research Center, Tabriz University of Medical Science, Tabriz, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Yazdchi
authors.affiliation: Neuroscience Research Center, Tabriz University of Medical Science, Tabriz, Iran.
authors.forename: Shiva
authors.initials: S
authors.lastname: Solahaye Kahnamouii
authors.affiliation: Neuroscience Research Center, Tabriz University of Medical Science, Tabriz, Iran.
authors.forename: Elyar
authors.initials: E
authors.lastname: Sadeghi-Hokmabadi
authors.affiliation: Neuroscience Research Center, Tabriz University of Medical Science, Tabriz, Iran.
authors.forename: Reshad
authors.initials: R
authors.lastname: Mirnour
keywords: COPD; neuropathy; visual evoked potential