An Investigation of the Visual Function in Maintenance Stage of Treatment with Methadone in Drug Addicted Individuals

Document Type : Original Article

Authors

1 Refractive Errors Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

2 Department of Optometry, School of Paramedicine Sciences, Mashhad University of Medical Sciences, Iran

3 Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Iran

Abstract

Purpose:
Visual functions are one of the most important factors influencing daily activities of an individual life. Some medications, however, may affect visual function.Methadone is one of the medications used in drug withdrawal both in detoxification and maintenance stages. Evaluation of visual functions in response to continuous use of methadone is essential to increase our understanding of the methadone effects and improve visual care in these patients, which is the goal of the present study.
Methods:
In this case control study, 30 drug addicts admitted to drug withdrawal clinicswith mean age of 40.97 (SD=9.90) years were divided into two groups. The case group (with methadone consumption of more than six months) contains 20 addicts and control group (with individuals who has just entered the maintenance stage of drug withdrawal) contains 10 addicts. Several visual function examinations performed: visual acuity, contrast sensitivity, visual field, and stereopsis.
Results:
In this study, no significant differences were found between groups in static visual acuity and visual field. Contrast sensitivity in 3(p=0.03), 6 (p=0.001), and 18(p=0.00003) cycle per degree frequencies were statistically significant between groups. Stereopsis also reduced in response to prolonged use of methadone (p=0.04). Also, refractive errors in control group were 1D more minus compared to the case group.
Conclusions:
Because methadone is used for a long period of time in the maintenance stage of the drug withdrawal, problems caused by this medicine must be considered and necessary visual care in this field should be provided. 

Keywords


  1. Ansons A, Davis H: Diagnosis and management of ocular motility disorders. 3th ed. Blackwell publishing company 2001; 41-74.
  2. Kaufman P, Alm A: Adler`s physiology of the eye. 10th ed. Mosby 2003; 453.
  3. Strasburger H, Rentschler I, Juttner M: Peripheral vision and pattern recognition. J Vis 2011; 11(5):13.
  4. Standardized contrast sensitivity tests. Available at: http://www.vectorvision.com/csv1000-contrast-sensitivity
  5. Howard P, Rogers B: Binocular Vision and Stereopsis. 1th ed. Oxford University Press 1995; 2.
  6. Goldstei B: Sensation and Perception. 8th ed. Cangage learning 2009; 229-58.
  7. Angela M, Kunnen S, Kuttnig K, Mohan J: World drug report 2013;1.
  8. Fedotov Y: ATS_Global Assesment 2011;1 0-21.
  9. Naranjiha H, Hosseini R, Nouri R, Peymaneh M: Fast evaluation report of drug abuse in Iran 2006; 127.
  10. Sefatian S, Mir Akbari M, Ahmadi F, Ghambari M, Nayini A. Familiarization with artificial addictive drugs2005; 35-40.
  11. Grosvenor T. Primary care optometry, 5th ed; 9, 70, 127, 171.
  12. Adams A, Brown B, Flom M, Jones R, Jampolsky A. Alcohol and marijuana effects on static visual acuity. Am J Optom Physiol Opt 1975; 52(11): 729-35.
  13. Brown B,Adams J,Haegerstrom G,Jones T,Flom M. Effects of alcohol and marijuana on dynamic visual acuity. Perception and Pscycophysics 1975; 18(6): 441-6.
  14. Dawson W, Jiménez-Antillon C, Perez J, Zeskind J. Marijuana and vision-after ten years use in Costa Rica. Invest Ophthalmol Vis Sci 1977; 16(8): 689-99.
  15. Fredrick T, Frederick W, Wiley A, Kelly L. Clinical Ocular Toxicology. 7th ed. Elsevier Saunders 2014; 130-1.
  16. Firth A, Pulling S, Carr M, Beaini A: Orthoptic status before and immediately after heroin detoxification. Br J Ophthalmol. 2004;88(9):1186-90.
  17. Carvalho J, Danda D, Dantas H, Arraes T, Cavalcanti E: Blue-on-yellow perimetry in tobacco and alcohol consumers. Arq Bras Oftalmol. 2006;69(5):675-8.
  18. Barwatt J, Hofford R, Emery M, Wellman P, Eitan S, Differential effects of methadone and buprenorphine on the response of D2/D3 dopamine receptors in adolescent mice. Drug Alcohol Depend 2013; 132(3): 420-6.
  19. Domenic L, Trimarchi C, Piccolino M, Fiorentini A, Maffei L. Dopaminergic drugs improve human visual contrast sensitivity. Hum Neurobiol 1985; 4(3): 195-7.
  20. Blin O, Mestre D, Masson G, Serratrice G. Selective effects of low doses of apomorphine on  spatiotemporal contrast sensitivity in healthy volunteers: a double-blind placebo-controlled study. Br J clin Pharmac 1991; 32(5): 551-6.