optic nerve 2
TRANSCRIPT
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