title: The effect of levodopa and dopamine agonists on optic nerve head in Parkinson disease.
abstract: OBJECTIVE
  To evaluate the effects of levodopa and dopamine agonists on retinal nerve fiber layer using scanning laser ophthalmoscope.
  
  
  METHODS
  Forty-four patients with the diagnosis of Parkinson disease and receiving levodopa or dopamine agonist monotherapy were included in this prospective study. The control group consisted of 21 normal cases. The optic nerve head images were taken with Heidelberg Retina Tomograph; rim area, rim volume, mean retinal nerve fiber layer thickness, and the results of Moorfields regression analysis were calculated. The measurement results were evaluated with Kruskal Wallis test and Mann-Whitney U-test.
  
  
  RESULTS
  There was no significant difference in mean age among groups (p=0.093). Retinal nerve fiber layer was measured to be significantly decreased in cases with Parkinson disease (p=0.004) while rim area and rim volume did not show a significant change (p=0.224, p=0.804 respectively). Rim area, rim volume, and retinal nerve fiber layer were significantly greater in the group treated with levodopa while it was the thinnest in the group receiving dopamine agonists.
  
  
  CONCLUSIONS
  Levodopa can have a protective affect to retinal nerve fiber layer in Parkinson disease compared to dopamine agonists.
authors.affiliation: Department of Ophthalmology, School of Medicine, Afyon Kocatepe University, Afyonkarahisar, Turkey. gkumbar@ttnet.net.tr
authors.forename: G F
authors.initials: GF
authors.lastname: Yavas
authors.forename: O
authors.initials: O
authors.lastname: Yilmaz
authors.forename: T
authors.initials: T
authors.lastname: Küsbeci
authors.forename: F
authors.initials: F
authors.lastname: Oztürk
mesh_terms: D000368:Aged; D000977:Antiparasitic Agents / Q000627:therapeutic use*; D052160:Benzothiazoles / Q000627:therapeutic use*; D018491:Dopamine Agonists / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D018613:Microscopy, Confocal; D009898:Optic Disk / Q000187:drug effects* / Q000473:pathology; D010300:Parkinson Disease / Q000150:complications / Q000188:drug therapy* / Q000473:pathology; D000077487:Pramipexole; D011446:Prospective Studies; D017447:Receptors, Dopamine D1 / Q000819:agonists; D012162:Retinal Degeneration / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000473:pathology
chemical_list: D000977:Antiparasitic Agents; D052160:Benzothiazoles; D018491:Dopamine Agonists; D017447:Receptors, Dopamine D1; D007980:Levodopa; D000077487:Pramipexole