OPTIC ATROPHY …..This is a condition of atrophy of the optic nerve from various causes. Clinically different types of field defects may develop Ophthalmoscopic examination will reveal the following characteristics of the disc.
- Margin of the disc is clearly defined.
- Colour of the disc is white (Procelanous).
- Few capillaries can be seen on the disc.
- Lamina cribrosa is visible.
- Physiological cup is prominent.
CAUSES OF OPTIC ATROPHY
- Intracranial space occupying lesion (particularly pituitary tumours, craniopharyngioma and orbital tumours).
- Chronic glaucoma
4.Poisons, e.g. Quinine, Tobacco, Methyl alcohol, Arsenic, Lead, Streptomycin, Chloramphenicol, Isoniazid etc.
- Secondary to optic neuritis, retrobulbur neuritis and orbital tumours.
- Hereditary ataxias.
- Familial disorders: Tay-Sachs disease, Retinitis pigmentosa, Leber’s hereditary optic atraphy.
- Diabetic neuropathy.
- Vascular disorders and prolonged hypotension.
- Paget’s disease.
- Basal arachnoiditis and meningitis.
- Vitamin B12 neuropathy.
Foster Kennedy Syndrome.
In this condition there is optic atrophy on the affected side with contralateral papilloedema. On the ipsilateral side there is central scotoma and hemianopia. This is usually due to meningioma involving the optic groove but may also be seen in cases of aneurysms affecting the anterior communicating or internal carotid arteries and in frontal lobe tumour.
TYPES OF OPTIC ATROPHY
- Secondary, usually from papilloedema.
- Consecutive-secondary to retinal diseases including retinitis, choroido-retinitis etc.
The underlying causes should be treated.
As an adjunct therapy steroids and neurotropic vitamins may be used.