Approach to Disc Pallor and Automated Fields in Neuro-ophthalmology
- 1. Approach to Disc Pallor and Automated Fields in Neuro- ophthalmology Dr.Shah-Noor Hassan FCPS,FRCS(Glasgow)
- 2. Approach to Optic disc pallor Types of optic atrophy • Primary • Secondary • Consecutive • Temporal pallor • Glaucomatous
- 3. Primary optic atrophy • cause not detected ophthalmoscopically • eg, pituitary tumor, optic nerve tumor, traumatic optic neuropathy, multiple sclerosis ,toxic/nutritional • Fundus features of disc Color-chalky white Margins-sharp Demarcated cup Cup may be enlarged normal retinal vessels
- 4. Secondary optic atrophy • eg, papilledema, papillitis • Damage due to swelling of the disc with glial proliferation • Fundus features of disc Color-yellow waxy/dirty white Margins-blurred Obliterated cup Perivascular sheathing Retinal vessels attenuated
- 5. classification Pathologic classification • Ascending optic atrophy - follows damage to RGC/nerve fibre layer • Descending optic atrophy - retrolaminar optic nerve/chiasma/optic tract • Trans-synaptic degeneration- seen in patients with occipital damage incurred either in utero or in early infancy.
- 6. Unilateral optic atrophy Ischemic (anterior ischemic optic neuropathy, retinal occlusive disease) Compressive (orbital, anterior fossa) Inflammatory (demyelinating, infectious, Autoimmune, sarcoid) Traumatic Infiltrative
- 7. Bilateral optic atrophy Glaucoma Secondary to retinal degeneration Post-papilledema Congenital anomalies: hypoplasia, coloboma Methyl alcohol toxicity Inherited ON : LHON, Auto dominant Nutritional/toxic
- 8. Optic Atrophy • Varies from temporal pallor to chalky white • Due to changes in blood supply, axonal loss, glial tissue • Also nature and extent of injury/damage
- 9. Differentials • Axial myopia • Optic nerve hypoplasia • Brighter-than-normal luminosity • Optic nerve pit • Myelinated nerve fibers • Scleral crescent • Optic disc drusen • Tilted disc
- 12. Optic atrophy • Slight, moderate, severe • Diffuse or sectoral
- 13. Optic atrophy • Color of disc not indicative of atrophy • Often temporal side of disc has less color than nasal side • O.A diagnosis is based on -color of disc,changes in vessels,nf layer - v.a, color vn, VF, pupils,VER
- 14. 0ptic atrophy • In AION – Limited to upper and lower quad • Chiasmal lesions – temp and nasal pallor(bowtie or band atrophy) due to crossing nasal fibres being involved Also seen in eye contralateral to unilateral optic tract lesion
- 15. Causes of primary optic atrophy Idiopathic Demyelination Post inflammatory Toxic Inflammation of orbit, sinus and meninges Compressive Nutritional Hereditary
- 16. Causes of secondary optic atrophy • Anterior ischaemic optic neuropathy • Papllitis • Papilledema • Metabolic diseases (Diabetes)
- 17. Optic disc pallor Clinical approach • Demographic profile –Age - Gender - Race • Clinical history
- 18. Optic disc pallor Demographic profile • Age – most important of demographic parameters • No watertight compartments • Significant overlaps between age groups • Glaucoma can present with pallor at any age
- 20. Optic disc pallor • Gender can guide in favour of a diagnosis but not always • Male: LHON, Traumatic ON,Tapetoretinal deg,ToxicON,Occupational(heavy metal exposure), lead, arsenic,Nutritional(chronic alcoholism) • Female: MS, Meningioma, Autoimmune/collagen vasc dis.,Sheehan synd, ecclampsia
- 21. Optic disc pallor- Racial differences • Blacks – lower incidence of Ischaemic ON, better visual fn in IIH • Caucasians more likely for MS than Hispanics and Asians • Overall Optic atrophy more in blacks than whites
- 22. Optic disc pallor- Clinical history • Onset –over hrs or days- Optic neuritis, Iscemic ON, Traumatic ON Subacute- over few days – in demylenating, compressive • Course- resolved naturally, recurrent episodes- demyelinating residual poor vn ,progressive,protracted course- other pathologies
- 23. Optic disc pallor -History • Laterality - Unilateral – Typical ON NAION Traumatic ON Compressive - Bilateral - Toxic, Nutritional,Hereditary,Arteritic AION, Atypical Optic neuritis
- 24. Optic disc pallor - History • Systemic – fever, jaw claudication, palpitations, dyspnoea, hypertension,diabetes,thyroidTB etc • Ocular painful eye movements, diplopia, proptosis • CNS –Headache, vomiting,TIAs, motor deficits, paraesthesias etc. • Trauma • Family history • Medications- for toxic
- 25. Optic disc pallor –Ocular Exam • V.A. • Visual Fields • Color Vision • Pupils • Fundus – Disc color, cup, margins, vascularity(Kestebaum count -10 capillaries on disc. In optic atrophy<6) • RNFL Defects – Red free green filter exam
- 26. Optic disc pallor – diagnosis by optic disc appearance • Ischaemic – pallid edema - arterial attenuation,sheathing - superior /inferior disc pallor - Haemorrhages - fellow eye small cup-disc ratio(disc at risk)
- 27. Inferior disc oedema Dilated inferior veins Disc at risk
- 28. Optic disc pallor - Infective • Macular star • Mild pallor or oedema
- 29. Disc pallor- Toxic/nutritional • Temporal disc pallor, bilateral
- 30. Disc pallor-LHON/DOA • Temporal, occasionally diffuse
- 31. Optic disc pallor- Chiasma/tract lesion • Bowtie/band atrophy Glaucomatous Nonglaucomatous
- 32. Optic disc pallor • Compressive neuropathy – unilateral or bil edema – painless progressive pallor – shunt vessels
- 33. Optic disc pallor- papilloedema • Dirty grey pallor, bilateral, blurred margins, obscured cup and gliosis, attenuation of vessels
- 35. Disc pallor – systemic exam Look for • Nutritional deficiency • B.P • Anemia • Lymph nodes • CVS /CNS
- 36. Optic disc pallor-Ocular investigations At baseline and followup • V.A • Color Vn • Contrast sensitivity • VF • FFA(if necessary) • OCT • VER/ERG
- 37. Optic disc pallor- Investigations First line 1.Haemogram,peripheral smear,TLC,DLC 2.ESR 3.Mx 4.Chest Xray 5.MRI Head and Orbit with thin cuts and fat suppression 6.VDRL 7. LP(if reqd)
- 38. Optic disc pallor- Investigations 1.Sarcoidosis-Serum ACE, serum Ca, CT chest 2.Collagen dis- Immunology workup;ANA,RF 3.Nutritional- Serum B12, Folate levels 4.Toxic-heavy metal screening 5.TORCH 6.Hereditary-LHON mutation(full mitochondrial sequencing or common mutations 11778,3460,14484) 7.NMO ab for Devic’s. MRI Spine 8. Thyroid functions- T3,T4 and TSH levels
- 40. VF testing strategies • Confrontation • Goldmann kinetic or static • Humphrey static automated
- 42. Presentation Outline 1. General aspects of automated perimetry 2. Components and basics of interpreting visual field reports 3. Physiological basis of visual field defects in neurological afflictions 4. Clinical examples discussing the topographic representation of visual fields 5. Visual field alterations in neuro-ophthalmological afflictions 6. Algorithm for field assessment and interpretation 7. Review of various field defects
- 43. Why choose automated perimeters: Humphrey perimeter Advantages of Automated Perimetry •Provides more sensitive and reproducible results •Provides quantitative information •Provides results in a more timely and precise manner •Experienced perimetrist is not required Advantages of Static Perimetry •Scotomas better defined •Temporal summation of stimulus possible •Less dependence on Perimetrist
- 44. Patient Information • Name • Age • Refractive Error • Visual acuity • Pupil Diameter • Stimulus/Target • Strategy • Fixation • Gaze monitor Reliability Indices • Fixation Losses • False Positive • False Negative • High fixation losses maybe pseudolosses due to misalignment or true in cases of central vision loss • High FP rates almost always indicate unreliable test • High FN rates in abnormal fields are common in perfectly attentive patients • In normal visual field it shows patient was inattentive Test Parameter
- 45. • Any Patient with visual loss unexplained on Ocular or refractive basis should have a visual field examinatin as the very next test.
- 46. Extent of normal visual field • Nasally 60 degrees • Superiorly 60 degrees • Inferiorly 70 to 75 degrees • Temporally 100 to 110 degrees
- 47. Interpretation of Humphrey visual Field
- 48. Why is the Grey scale plot suited for field assessment in Neuro-ophthalmology cases • Optic nerve diseases are more likely to result in absolute field losses • Absolute field defects are very clearly demarcated on grey scale plots • These visual fields often respect the vertical meridians and these are well defined on grey scale plots • Orientation of scotoma with respect to the blind spot is best appreciated on the grey scale plots
- 49. Effects of distortion or obscuration • Of light entering eye by eyebrows, skin of lid Lens rim, spectacle power(high plus/minus),incorrect lenses • By eyelids and media Pupil size,opacities in media
- 50. Basis of visual field defect • Anatomical structure of retinal nerve fibres- which has 4 groupings which enter Optic disc a.Inf. Ret n. fibres subserve Sup. visual field b.Sup. Ret. N. fibres – Inferior visual field c.Fibres bet macula & optic disc(papillomac bundle)- central Vn d.Nasal fibres which enter disc in wedge shaped manner
- 51. Basis of field defect • Superior and Inferior fibres form arcuate bundles around papillomacular bundle to enter optic nerve at 12 o’ clock and 6 o’ clock • Peripherally in retina they join horizontal raphe. Fibres do not cross horizontal raphe. • Arcuate n.f.bundle –arcuate field defect. Nasal extent is hor. Meridian • Pap-mac bundle-central or centrocaecal scotoma • Nasal wedge-temporal defect
- 52. Basis of field defects • Optic disc lesions will produce VF defects identical to those of retina • Posteriorly fibres rotate 90degrees • Macular fibres occupy central core of Optic nerve • Hence retrobulbar optic nerve lesions produce more central scotomas.
- 54. Basis of Visual Field Defects in Neuro-Ophthalmology
- 55. Arrangement of nerve fibres along the course of visual pathway Lateral Geniculate Body Upper retina fibers - medial part Lower retina fibers - lateral part Macular fibers -posterior 2/3
- 56. Preview of field defects seen in neuro-ophthalmology
- 57. Topographic principle of visual field alterations in ret vasc dis CRVO (Non-ischemic) BRVO BRAO PRP done for Diabetic Retinopathy
- 58. Visual Field alterations in nerve fibre layer affliction
- 59. Visual field changes in neuro-ophthalmology 1. Optic disc pit 2. Tilted optic disc 3. Optic disc drusen 4. Anterior ischemic optic neuropathy 5. Papilledema 6. Hereditary optic atrophy 7. Toxic optic neuropathy 8. Optic neuritis 9. Optic nerve meningioma 10. Pituitary adenoma 11. Craniopharyngioma 12. Optic tract and LGB lesions 13. Optic radiation afflictions 14. Visual cortex lesions 15. Miscellaneous field alterations
- 60. Optic disc pit Tilted optic disc Crater like optic disc pit Optic Disc Drusen 60° field Optic Disc Drusen Optic Disc Drusen 30° field
- 61. AION with cecocentral sparing Typical AION Maculopapular ischemia
- 62. Papilledema (IIH) Hemorrhagic Papilledema Papilledema secondary to astrocytoma
- 63. Principle behind cecocentral scotoma Hereditary optic nerve atrophy Toxic optic neuropathy
- 64. Visual Field defects in optic neuritis Central Diffuse depression Altitudnal Nasal hemianopia Nerve fibre bundle defects Combined defects
- 65. Orbital apex meningioma –alt defect Optic nerve sheath meningioma Sphenoid ridge meningioma with left orbital apex involvement
- 66. Field alterations in chaismal and perichiasmal lesions Junctional scotoma in a case of sphenoid meningioma
- 67. Pituitary Adenoma Early stage of pituitary adenoma
- 68. Late stage pituitary adenoma- Hemianopia and subtotal defects
- 70. Field alterations in optic tract and lateral geniculate body lesions Basal Ganglia neoplasm: Incongruent Hemianopia
- 71. Field alterations in lesions involving optic radiations Astrocytoma of left temporal lobe Substance defects in left brain Infarct of left occipital and parietal lobe
- 72. Complete hemianopia in total involvement of all optic radiations Hemianopia with sparing of fixation in subtotal in involvement of all optic radiations Involvement of all optic radiations after left cystic tissue defect following neurosurgery
- 73. Incongruent field losses in occipital lobe infarct affecting the optic radiations asymmetrically Incongruent field losses in multiple sclerosis seen in a 30-2 field Incongruent field losses in multiple sclerosis are better demarcated in this 10-2 field
- 74. Field alterations in afflictions of the visual cortex Congruent homonymous hemianopia with macular sparing Occipital lobe infarct with complete homonymous defects Occipital lobe infarct with incomplete homonymous defects
- 75. Miscellaneous Field Defects Peripheral field defects • May be out of field for 30-2 • A fast 60-2 protocol used Bilateral homonynous hemianopia • Seen in vascular lesions • May have both congruent and incongruent areas
- 76. Miscellaneous Field Defects Central homonymous hemianopia • Seen in occipital lobe abscess • Also called reading scotoma Functional visual field loss • No organic lesion
- 77. Localisation of homonymous hemianopia • Macular sparing • Congruity • Pupillary response – normal in Op Radiation • Asymmetric OKN -Parietal • Saccadic pursuit to side of lesion-parietal
- 78. Algorithm for Field Assessment and Interpretation
- 79. • References 1. Field charts referenced from Atlas of Computerized Perimetry by Weber and Caprioli, Published by W.B. Saunders Co.Philadelphia,2000 2.Clinical Neuro-Ophthalmology by Ulrich Scheifer et al,Publishers,Springer
- 80. THANK YOU