Optic neuritis is seen in all except:
D i.e. None Optic Neuritis It is an inflammatory or demyelinating disorder of the optic nerve (from the optic disc to the lateral geniculate body Aetiology 1. Idiopathic 2. Demyelinating diseases Multiple sclerosis Q Neuromyelitis optica (Devic's disease)Q Leucodystrophies Schilder's adrenoleuco-dystrophy Krabbe's galacto cerebroside dystrophy Metachromatic sulfatase deficiency Pelizaeus - Merzbacher disease Post viral e.g. measles, mumps, chicken pox, whooping cough &, glandular fever and immunization. 3. Metabolic / Nutritional Deficiency Vitamin B1,135, B12 deficiency Q (beri beri, pellagra & pernicious anemia respectively) Thyroid dysfunction Diabetes Neuropathy with pregnancy & lactation 4. Leber's hereditary optic neuritis Toxic Drugs - Quinine Q, chloroquine Q, Ethambutol Q, Digitalis Q, streptomycin, INH, Amiodarone, Vigabatrin, NSAID's (aspirin, indomethacin, ibuprofen, phenylbutazon Tobacco Q, ethyl & methyl alcohol Q, lead, cannabis indica, arsenic, carbon di sulphide. 6. Ischemic * Aeritic - Giant cell aeritis * Non aeritic Takayashu's disease PAN SLE 7. Infections Infections of the adjacent structures e.g. uveitis, retinitis, meningitis, orbital cellulites, sinusitis etc. Granulomatous infections e.g. TB, sarcoidosis, syphilis etc. * Peculiar feature of neuroretinitis Types Clinical features Optic neuritis typically affects the patient between 20-40 years of age (but post viral type typically seen in children) and presents with: Symptoms Monocular sudden, progressive and profound (<6/60) loss of vision Q Visual loss progresses very rapidly & usually maximal by the end of 2nd week. Pain behind eye ball especially when the eye is moved superiorly due to attachment of some fibres of superior rectus to duramater (this feature is especially seen in retrobulbar & perineuritis) Signs Local tenderness at the site of attachment of superior rectus Decreased visual acuity (usually < 6/60) Q Decreased colour vision (red, green are more affected) Defective contrast sensitivity Defective depth perception of moving objects (Pulfrich phenomenon) Worsening of symptoms with exercise or increase in body temperature (Uhthoff sign) Pupillary reactions may be Sluggish and ill sustained Q Relative afferent pupillary defect (RAPD or Marcus Gunn's pupil) Q detected by swinging flash light test. Visual field defects Most common field defect is central or centrocaecal scotoma Q Other defects are paracentral, arcuate, sectorial, and altitudinal field defects. Opthalmoscopic features of papillitis resemble early papilloedema. There is hyperemia (1st sign), blurring of disc margins, disc oedema with obliteration of physiological cup; touous, congested and distoed retinal veins with or without peripapillary flame shaped haemorrhages. Even in most severe cases however the swelling of the disc rarely exceeds 2-3 D (in papilloedema 3-6D) Visual evoked potential show latency and delay in amplitude Q - It is commonly due to infectious aetiology and not seen in multiple sclerosis (m.c. cause of papillitis & retrobulbar neuritis) - Macular star is seen due to inflammation of neighbouring retina - Fundus appears normal ophthalmoscopically Q (occasional temporal pallor present) - typically defined as neither the ophthalmologist nor the patient sees anything. * Specific features of Retrobulbar neuritis - Fundus appears normal ophthalmoscopically Q (occasional temporal pallor present) - typically defined as neither the ophthalmologist nor the patient sees anything. - Mild pain on ocular movements & tenderness at the site of attachment of superior rectus tendon.
DM
Methanol poisoning
Multiple sclerosis
None