optic nerve 2

Evaluation of optic nerve disease

Clinical features of optic nerve dysfunction

• Reduced visual acuity

• Afferant pupillary defect

• Dyschromatopsia

• Diminished light brightness sensitivity

• Diminished contrast sensitivity

• Vsual field defects

Optic disc changes1 –Normal disc2-Disk swelling 3-optico-ciliary shunts4-optic atrophy

Optic atrophyprimary optic atrophy

• A; causes • Following retrobulbar

neuritis• Compressive lesions

such as tumors and aneurysms

• hereditary optic neuropathies

• Toxic and nutritional optic neuropathies

Disc appearance

• White flat disk with clearly delineated mar gins

• Reduction in number of blood

• Crossing the disk • Attenuation of

prepapillary vessels

Secondary optic atrophy

Causes papilloedema

papillitis

AION

Disc appearance white

slightly raised

poorly delineated margin

Special investigation

Automated perimetry

MRI

Visual evoked potential

Fluorescein angiography

Classification of optic neuritis• 1-Ophthalmoscopic classification

• a; retrobulbar neuritis

• b; pappillitis

• c; neuroretinitis

• 2-Aetiological classification• a; demyelinating

• b; parainfectious

• c; infectius

Optic neuriotis and demyelination

• VISUAL PATHWAY LESIONS

• BRAIN STEM LESION

Demyelination diseases

• Isolated optic neuritis

• Multiple sclerosis

• devic disease

• Schilder disease

Systemic feature of MS

• Spinal cord lesion

• Brain stem lesion

• Hemisphere lesion

• Transient phenomena

Special investigation

• Lumbar puncture• VEP• MRI

Optic neuritis

• 70% of women and 30% of men develop MS

• Evidance of optic neuritis in 70% of MS

• In 70% of isolated optic neuritis abnorml MRI

• Risk of MS winter onset HLA DR2 & uthuff

presentation

• Sudden onest of visul loss

• discomfort in or around the eye

• Frontal headache tenderness of globe

signs

• Normal disc in two-thirds (retrobulbar)

• Diminished visual acuity (very mild –very sever)

• Impairment of visual acuity & contrast sensitivity

• Visual field defect (central scotoma)

Clinical course

• Impairment of visual acuity becomes maximum after 1-2 weeks (6/18-6/60)

• Recovery takes 4-6 weeks usually

Prognosis

• Excellent in 75% (V/A 6/9)

treatment

• In mild visual loss treatment is probably unnecessary

• When visual acuity in the first week of symptom is worse than 6/12 treatment may speed up recovery

• Intravenous methylprednisolon sodium succinat

• Treatment dose not appear to have any long term benefit on final visual acuity

Other causes of optic neuritis

• Parainfectious ON (Viral)• Infectios ON (sinus related,syphlis,lyme,…

signs

• Pale disc

• Diffuse or sectoral edema

• Localized disc hyperfluorescence

• V/A in 1/3 of patient is normal in remainder have moderate to sever impairment

• Visual field defect is typically altitudinal

• Color vision is diminished

managment

• Serologic study

• Fasting lipid profile

• Blood glucose, fibrinogen & packed cell volume

Treatment

• Treatment of any underlying diseases

• Stop smoking

• Low-dose aspirin

Arteritic anterior ischemic optic neuropathy: clinical features of

giant cell arteritis• Scalp tenderness• Jaw claudification• Polymyalgia rheumatica• Neck pain, weight loss,

anorexia fever, night sweets, malaise depression

• Superficial temporal arteritis

• Arteitis of other arteries• Occult arterritis

Arteritic anterior iscxhemic optic neuropathy

• Uniocular sudden and profound loss of vision

• Periocular pain

• Transient visual obscuration

• Flashing lights

Signs

• pale and swollen optic disc

• Splinter hemorrhages• Finaly optic atrophy

Special investigation

• ESR• C-reactive protein • Temporal artery

biopsy

treatment

• Intravenous methylprednisolon 1g/day for 3 day together with oral prednisolon 80 mg

• After 3 days 60 mg for 3 day than 40 mg/days

• Than daily dose reduced 5 mg weekly

• Maintanance is 10 mg

Papillodemacauses

• Space-ocupaying lesion

• Blockage of the ventricular system

• Obstruction of CSF absorption

• Benign intracranial hypertention, diffuse cerebral edema, sever hypertention

• Hypersecretion of CSF

Early papillodema

• Visual symptom are absent ,V/A normal

• Hyperaemia and mild elevation in optic disc

• Indistinct disc margin• Absent spontaneous

venous pulsation• Nasal margin is

blured in first

Estabilished papillodema

• Transient visual osscuration• V/A is normal or reduced • Sever hyperemic optic disc• Smal vessele obscured• Venous engorgment flam

shap hemorrhage• Cotton-wool spots• Hyperfluorescence• Retinal fold• Hard exudates• Enlarge blind spot

Long standing papillodema

– V/A variable– V/F constriction– Cotton-wool and

hemorrhage absent– Optociliary shunts

Atrophic papillodema

• V/A sever diminish• White optic disc

Differential diagnosis

• Malignant hypertention

• Bilateral papilitis

• Bilateral compressive thyroid orbitopathy

• Bilateral simultaneousanteriorischemic optic neuropathy

• Bilateral compromisedvenous drainage

Congenital optic nerve anomalies