optic atrophy

Optic atrophy

Angel Das

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

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

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

o Disc is chalky whiteo Margins well definedo Lamina cribrosa seeno Cupping is shallowo Retina looks normal

Ophthalmoscopic appearance

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

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

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

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)

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

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

Ophthalmoscopic Appearence

-pallor of disc

-decrease in no: of small blood vessels (kastenbaum index)

Treatment

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