Alcohol and tobacco abuse-related optic neuropathy

The optic nerve is responsible for sending visual information from the eye to the brain. The term "optic neuropathy" refers to a lesion or loss of functionality in the optic nerve which can have multiple causes such as infections, inflammations, tumours, ischaemia (lack of blood flow), trauma, hereditary anomalies, nutritional deficits and toxic substances. 

The optic nerve is vulnerable to different toxic substances including alcohol and tobacco. 

Alcohol- and tobacco-related optic neuropathy is a uncommon pathology, as it is more associated with pipe or cigar tobacco (increasingly declining in use) than cigarettes.  

On the other hand, alcoholism is usually associated with a nutritional and vitamin deficit which contributes or predisposes a patient to a greater extend to toxicity of the optic nerve. Therefore, alcohol, tobacco and malnutrition are factors causing this type of optic neuropathy. 

The main symptom is a painless loss of vision with an insidious onset that slowly advances. Initially, the patient notes blurriness in the central visual field, followed by reduced visual acuity, which may have a variable evolution.

Sometimes it can end up being quite severe. The loss of vision is in both eyes, although in the initial phases it might be asymmetrical and more predominant in one eye than the other. There is also a change in colour perception (dyschromatopsia). 

In the exam of the back of the eye, the head of the optic nerve (optic papilla) usually appears as normal in the large part of cases in the initial stages.

After a variable period of time, the papillae gradually evolve becoming pale. The whole optic nerve may become atrophied with a permanent loss of vision if tobacco and alcohol consumption is not stopped as soon as possible. 

The campimetry or visial field tests typically record central or centrocecal bilateral and relatively symmetrical defects.

A colour test confirms dyschromatopsia, which is predominant in the red-green axis. A blood test is useful in ruling out nutritional deficits or vitamin deficiencies. 

In addition, it allows us to exclude the possibility of an infection or inflammation as the cause of the change in the optic nerve.

Frequently, it will be necessary to obtain neuroradiological exams to rule out the presence of a tumour or compressive lesion as the cause of the neuropathy. The test of choice is the nuclear magnetic resonance exam.

Treatment involves immediate and permanent suspension of alcohol and tobacco consumption. On doing so, a gradual recovery and a slow improvement in the visual issues are seen, unless the optic nerve damage is very severe and/or advanced. 

A healthy and balanced diet with vitamin supplements including vitamin B12 is recommened.

Alcohol and tobacco abuse, which have negative effects on the body, may also damage our eye health. 

Excessive consumption of these drugs can damage the optic nerve, which may cause a severe loss of vision if consumption is not stopped early.