Best Vision Eye Hospital

Toxic Optic Neuropathy


What is toxic optic neuropathy (TON)?

What are the causes of Toxic Optic Neuropathy ?

Toxic optic neuropathy refers to visual impairment due to optic nerve damage 

caused by a toxin. It is characterized by bilateral, usually symmetric vision loss, 

Papillomacular bundle damage, Central (or) ceocentral, Sctoma & reduced color vision.

Toxic optic neuropathy is caused by the damage to the optic nerve through different toxins, including drugs, metals, organic Solvents, methanol & carbon dioxide.

Tests at hospital -

  • Visual acuity test.
  • Color vision test. is Important
  • Relative afferent.
  • Pupillary defect (RAPD).
  • Visual field test (HVF).

Patient Complaints -

  • Blurred vision.
  • Discomfort.
  • Redness.
  • Watering Eyes.

Treatment -

(1) Removing the toxic substance.
(2) discontinuation of drugs
(3)stop smoking (or) consumption of alcohol.

Eye Check up includes visual acuity, colour un visual field, Pupil-reaction and optic disc examination. Prognosis depends on the dosage & duration of exposure to toxic substance. usually, after discontinuation. vision improves to normal over several days (or) weeks.