Optic atrophy

Optic atrophy

1. Optic atrophy Angel Das

2. Optic Atrophy Condition of optic disc following degeneration of optic nerve Occurs as result of any injury to nerve fibres involving in anterior visual system – retina to lateral geniculate body

3. Classification Ophthalmoscopic Classification -Primary Optic Atrophy - Secondary/Post- neuritic Optic Atrophy -Consecutive Optic Atrophy -Glaucomatous Optic Atrophy - Ischaemic Optic Atrophy Another classification -Ascending/Anterograde optic atrophy -Descending/retrograde optic atrophy

4. Primary optic atrophy Disease proximal to the disc so there is no evidence of local inflammation . CAUSES : Multiple sclerosis Space occupying lesions Leber’s disease Tabes dorsalis

5. Disc is chalky white Margins well defined Lamina cribrosa seen Cupping is shallow Retina looks normal Ophthalmoscopic appearance

6. Secondary/Post neuritic Optic Atrophy Break in continuity of fibres in optic disc Occurs in longstanding papilloedema , papillitis or neuroretinitis Ophthalmoscopic Appearance -Disc- dirty white -Edges blurred due to gliosis(proliferation of astrocytes & glial tissue) -Cup obliterated

7. Consecutive Optic Atrophy Occurs following destruction of ganglion cell- secondary to lesions in choroid /retina Causes -Diffuse chorioretinitis -Retinitis pigmentosa -Pathological myopia -Occlusion of central retinal artery

8. Ophthalmoscopic Appearence -Disc – yellow waxy -Edges – not well defined -Retinal vessels attenuated

9. Glaucomatous Atrophy Results from long-standing raised IOP Ophthalmoscopic Appearence -Deep & wide cupping of optic disc -Nasal shift of blood vessels -Lamina cribrosa pores seen (lamellar dot sign)

10. Conditions producing disc ischaemia Causes -Giant cell arteritis -Severe haemorrhage -Severe anaemia -Quinine poisoning Vascular / Ischaemic Optic Atrophy Ophthalmoscopic Appearence -pallor of disc -marked attenuation of vessels

11. Clinical Features Loss of vision -partial /total Pupil -semi-dilated -direct light reflex –sluggish /absent -Marcus Gunn pupil/RAPD Visual field loss -Peripheral, Central /Eccentric

12. Ophthalmoscopic Appearence -pallor of disc -decrease in no: of small blood vessels ( kastenbaum index)

13. Treatment Partial optic atrophy – treat underlying cause If complete atrophy – vision cannot be recovered