Toxic Amblyopia
From WebHealth
[edit] Toxic amblyopia (=optic neuritis) Introduction
Several toxic substances and a lack of certain vitamins can lead to a loss of vision. It has been known for some time that alcohol and tobacco, particularly when used excessively, can cause visual damage. It seems to be a direct toxic effect on the nerve fibers of the optic nerve.
In 1992 there was an epidemic in prisoners of war in Cuba where peripheral neuropathy (loss of feeling in the skin) and optic neuropathy occurred frequently in those who smoked a lot of cigars and who lacked a good protein source in their diet. With vitamin A and B-complex supplements and balanced food intake including protein the epidemic stopped.
| Common causes of toxic amblyopia |
| alcohol (possibly due to lack of vitamin A and vitamin B-complex intake in chronic alcoholics) |
| excessive cigarette and cigar smoking |
| lead |
| mercury |
| methanol (often contained in cleaning agents) |
| drugs like digitalis, ethambutol, and other drugs |
Signs and symptoms:
There is a loss of vision that can not be corrected with glasses beyond a certain degree. Circumscript visual field losses develop (called scotomas. Note: with this link pull right bar down to lower 1/5 position to see animated scotoma development). Scotomas are assessed with detailed visual field tests.
Diagnostic test:
No abnormalities are usually seen in the fundus. Only late cases that lead to blindness show the signs of optic atrophy. An MRI scan of the optic chiasm and the optic nerves may be indicated.
Treatment:
Treatment consists of removing all toxic substances out of the environment and food and to change unhealthy lifestyles into healthy ones. Here is a link to a more detailed review of toxic/nutritional amblyopia (=optic neuropathy).
| Home page | Eye diseases | Optic nerve problems |
References:
1. The Merck Manual: Toxic amblyopia
2. Eye conditions: http://www.stlukeseye.com/Conditions/
3. Karolinska Institute Library eye disease links
4. Ferri: Ferri's Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc.
5. Rakel: Conn's Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier
