Discussion:
Methanol poisoning can cause vision loss with damage to the visual
pathways3. Studies have shown that the myelin sheath
of the retrolaminar optic nerve is selectively vulnerable to methanol
poisoning due to its anatomical structure 4,5.
Accumulation of formic acid metabolites is the cause of retinal and
optic nerve damage. Depending on the severity of the poisoning and the
duration of exposure to formic acid, this damage to visual structures
may cause permanent vision loss 6.
Visual impairment due to methanol
poisoning usually occurs bilaterally, but rare cases of unilateral
vision damage have also been reported in two studies6,7. which they stated may be due to anatomical or
structural variation. Treatment maybe the reason of vision improvement
and some studies have reported improvement in vision loss after
poisoning treatment8, but the return of vision was not
symmetrical in our patient’s eyes.
In conclusion such abnormal case reports can help to raise awareness of
the diversity of the sequela of methanol poisoning.
Conflict of interest :
The authors declare there is no conflict of interest.