Sony Attri, D.Optom

Fellow Optometrist, Vitreo-Retina Department, Dr. Shroff’s Charity Eye Hospital, New Delhi, India

 

It is the time to be wise in limiting the consumption of alcohol to occasions, dinner and get-togethers. Like other toxic effects, long–term alcohol consumption has been documented as contributing factor for ocular disease associated with other medical fields.(1)

Some ocular conditions associated with long–term alcohol consumption are acute methyl alcohol optic neuropathy, congenital ocular disease, chronic alcoholism and intoxication in the eye.(2) According to the definition, any type of drink containing 14 gm alcohol known as standard alcohol.(3) Ethanol intoxications have significant effect on the visual functions along with central nervous system (CNS) through reducing Gamma–aminobutyric acid (GABA) activity.(4) GABA usually found in different parts of visual pathway, from retinal ganglion and bipolar cells to the lateral geniculate nucleus, superior colliculus and the visual cortex.(5) Eye tracker helps to record eye movements during completion of Visual Maze test which helps to evaluate high latency for fixation, increased duration of fixations and increased frequency of saccades.(6) Alcohol weakens the muscles of the eye that can damage optic nerve by preventing the interaction of the brain and eyes.

Acute optic neuropathy is considered as the main ocular damage due to methanol intoxication followed by inner segment lesions of the retinal photoreceptors where rods are more affected compared to cones through several studies.(7) Blurring of vision, visual hallucination, dense central scotoma, and decreased visual acuity are the common symptoms found in methyl alcohol intoxication. Nystagmus, sluggish pupils, disc swelling, and optic disc hyperaemia are the main signs.(8) Intravenous high–dose methylprednisolone may be effective for vision recovery for these patients.

Short palpebral fissures, epicanthus, ocular hypertelorism, coloboma, strabismus, blepharoptosis, microphthalmia, and abnormalities of the fundus, presence of these ocular findings related to Fetal Alcohol Syndrome (FAS).(9) It is believed that eye diseases occur in over 90% of children with the FAS.

Chronic alcoholism has an impact in the eye in the form of Age–related macular degeneration (AMD), Retinal Vein Occlusion (RVO), Optic Neuropathy, Glaucoma and Cataract.

AMD is a frequent cause of blindness among the elderly in developed countries. It is believed that along with antioxidants some protective nutrients against AMD, such as Zinc and Vitamin are also found in reduced level among in heavy drinkers compared to non-drinkers through numerous epidemiological studies.(10)

Alcoholic liver disease can be the aetiology of bilateral multifocal Central serous chorio-retinopathy (11) (CSCR). In Beaver Dam Eye Study (BDES) (12), drinking more than four drinks per day of alcohol was associated with asteroid hyalosis.

Associated with colour vision defects central or cecocentral scotoma due to papillomacular bundle damage is found in Toxic/ nutritional optic neuropathy secondary to chronic alcohol consumption.(13)

However, it has been found that alcohol may decrease the blood flow of the anteriorly located ciliary body by suppressing vasopressin, but optic nerve may receive more blood when alcohol is present in the circulation. It can be protective against the development of primary open–angle glaucoma (POAG).(14)

Calcium homeostasis may lead to cataract formation by increasing intracellular lens calcium levels through inhibition of the calcium pumps on the lens fibres due to acute alcohol exposure.(15)

Ophthalmologists and Optometrists should consider and made their patients aware that alcohol consumption is modified risk factor for ocular diseases.

 

References:

  1. Wang S, Wang JJ, Wong TY. Alcohol and eye diseases. Surv Ophthalmol 2008;53:512–525.
  2. Weih LM, Mukesh BN, McCarty CA, Taylor HR. Association of demographic, familial, medical, and ocular factors with intraocular pressure. Arch Ophthalmol 2001;119:875–880
  3. Alcohol Research: Current Reviews Editorial Staff. Drinking Patterns and Their Definitions. Alcohol Res.2018;39(1):17–18
  4. Lobo IA, Harris RA. GABA(A) receptors and alcohol. Pharmacol Biochem Behav 2008;90:90–94
  5. Xiao C, Ye JH. Ethanol dually modulates GABAergic synaptic transmission onto dopaminergic neurons in ventral tegmental area: role of mu-opioid receptors. Neuroscience 2008;153:240–248.
  6. Silva JBS, Cristino ED, Almeida NL, Medeiros PCB, Santos NAD. Effects of acute alcohol ingestion on eye movements and cognition: a double-blind, placebo-controlled study. PloS ONE 2017;12:e0186061–e0186061.
  7. Baumbach GL, Cancilla PA, Martin-Amat G, Tephly TR, McMartin KE, Makar AB, et al. Methyl alcohol poisoning. IV. Alterations of the morphological findings of the retina and optic nerve. Arch Ophthalmol 1977;95:1859–1865.
  8. Ashurst JV, Nappe TM. Methanol toxicity. In: StatPearls. Treasure Island, FL: StatPearls Publishing LLC.; 2019
  9. Brennan D, Giles S. Ocular involvement in fetal alcohol spectrum disorder: a review. Current pharmaceutical design. 2014;20
  10. Ritter LL, Klein R, Klein BE, Mares-Perlman JA, Jensen SC. Alcohol use and age-related maculopathy in the Beaver Dam Eye Study. Am J Ophthalmol 1995;120:190–196.
  11. ittl MK, Spaide RF, Wong D, Pilotto E, Yannuzzi LA, Fisher YL, et al. Systemic findings associated with central serous chorioretinopathy. Am J Ophthalmol 1999;128:63–68
  12.  Moss SE, Klein R, Klein BE. Asteroid hyalosis in a population: the Beaver Dam eye study. Am J Ophthalmol 2001;132:70–75.
  13. Kesler A, Pianka P. Toxic optic neuropathy. Curr Neurol Neurosci 2003;3:410–414.
  14. Kojima S, Sugiyama T, Kojima M, Azuma II, Ito S. Effect of the consumption of ethanol on the microcirculation of the human optic nerve head in the acute phase. Jpn J Ophthalmol 2000;44:318–319.
  15. Zeng J, Borchman D, Paterson CA. Acute effect of ethanol on lens cation homeostasis. Alcohol 1998;16:189–193.