Optic Disc Swelling

An approach to the diagnosis of disc swelling with its etiopathology

1. Welcome

2. Optic Disc Swelling Dr. Tareq Esteak Resident( Neurology) NINS

3. Outline Anatomy of Optic Nerve Blood supply of Optic Nerve Applied anatomy Pathogenesis Differentials

4. Anatomy of optic nerve An outgrowth of brain 2 nd cranial nerve Comprised of axonal extension from ganglionic cell of retina Optic disc to chiasma Not covered with neurilemma : doesn’t regenerate when get cut Sorrounded by meninges unlike other cranial nerves

5. Parts of optic nerve Intraocular Intraorbital Intracanalicular Intracerebral

6. Intraocular Part Lamina Cribrosa Meninges Meninges

7. Arterial Supply: Optic Nerve PION CRAO AION

8. Blood supply of optic nerve

9. Venous Drainage Optic nerve head : Central ratinal vein Orbital part: Central retinal vein,Pial plexus Intracranial part: Pial plexus<anterior cerebral vein

10. Applied antomy Papilledema occur as prelaminar axons swells from statis of axoplasmic flow at the level of lamina cribrosa. Insufficient blood flow through posterior ciliary artery due to hypotension, thrombosis, vascular occlusion, vasculitis(GCA) causes Optic nerve head infraction in leading to AION( optic disc swelled). Insufficient blood flow through pial vasculature due to hypotension, thrombosis, vascular occlution , vasculitis(GCA) causes Optic nerve infraction post-laminar leading to PION ( optic disc normal).

11. Applied antomy Intracanalicular part of optic nerve is vulnarable to injury in skull fracture. Intracranial part of optic nerve is usually compressed due to internal carotid artery aneurysm CRVO : Papilledeama with widespread hemorrhage. CRAO : Pale Retina with cherry red spot.

12. Optic Disc swelling Optic disc swelling or disc edema may be defined as swelling of optic nerve anterior to lamina cribrosa . When found must be differentiated from Pseudopapilledema Pseudopapilledema mostly congenital and physiological , doesn’t need further workup True Disc swelling is associated with numerous condition

13. Differentials of Optic Disc swelling True disc swelling Elevated ICP(Papilledema) Optic Neuritits Neuroretinitis Anterior Ischemic Optic Neuropathy(AION) Diabetic papillopathy Hypertensive retinopathy Compressive neuropathy: Meningioma ,Lymphangioma, lymphoma Pseudopapilledema Drusen Myelinated nerve fiber Hypermetropia

14. Papilledema Pseudopapilledema Definition Disc swelling due to raised ICP Appearance of disc swelling not due to any disease state Cause ICSOL,IIH, malignant hypertension Drusen, Myelinated nerve fiber, Hypermetropia Symptoms Transient vison loss, enlarged blind spot Usually asymptomatic, sometimes Arcuate scotoma Fundoscopy Disc Small cupless /ill-defined cup Loss of cup occurs late Color of Disc Hyperemic Yellowish Obscuration of disc blood vessel present absent Spontaneous Venous pulsation absent present Exudates May be present absent Fluorescein dye angiography Dye leaks in disc No leakage

15. Papilledema Drusen Both disc are swollen with obscuration of disc margins and vessel at disc Retinal hemorrhage Disc is elevated with visible yellowish deposits within the optic nerve head

16. Papilledema Drusen Disc swelling, venous engorgement, and vessel leakage shown by fluorescein angiography, Undilated capillary network with no leakage of dye into the peripapillary region. Discrete foci of hyperfluorescence with late staining of the drusen.

17. Drusen ( CT- Orbit/head) C alcification of the optic nerve insertion bilaterally USG of eye demonstrates calcified ( drusen) optic nerve head

18. Myelinated nerve fiber Hypermetropia White, feathery ,Fanned out lesion Simulates disc edema Central retinal vessel crows in small disc congested but no dialted vessels, Sponteneous venous pulsation present

19. Approach

20. Papilledema Once true disc swelling is confirmed , it should be determined whether it is related to an optic neuropathy or raised ICP. Papilledema is usually reserve for optic swelling secondary to raised ICP All other disc swelling is called optic disc swelling or disc edema. Other of the major causes of disc edema other than papilledema is Papillitis or optic neuritis,AION

21. Pathogeneis : Papilledema

22. Causes of papilledema IIH( Idopathic Intracranial Hypertension) Increased venous pressure : SSST ( superior Sagittal Sinus Thrombosis) ICSOL: Tumor ,Abscess, Large hematoma Meningeal process: Infection, inflammation, neoplastic Hydrocephalus

23. Papilledema : Grading ( The Frisen scale)

24. Normal Disc : grade 0

25. Grade 1

26. Grade 2

27. Grade 3

28. Grade 4

29. Grade 5

30. Anterior Optic neuropathies Etiology Inflammatory . e.g.Optic Neuritis(Papillitis) Ischemic .e.g. AION Compressive Optic neuropathy Toxin induced.e.g . Methanol, ethelene glycol Heriditary.e.g . Leber’s optic neuropathy Infiltrative.e.g . sarcoisosis Pathogenesis

31. Papillitis ( Optic neuritis) Inflammation of optic papilla or optic disc is called papillitis or optic neuritis Usually associated with pain ,specially on eye movement Dimness of vision On examination: Imapired optic nerve function, Central scotoma , RAPD present Underlying disease :Demyelinating disease MS, NMO-SD, If associated with retinal inflammation called neuroretinitis Neuroretinitis usually never demyelinating. Causes include Toxoplasmosis, Viral infection(CMV), Syphilis , Sarcoidosis.

32. MS NMO T2WI- shows increased signal intensity in small segmnt of left optic nerve T2WI-shows increased signal intensity in large segment in left optic nerve

33. MRI : MS; NMO typical site Multiple sclerosis Neuromyelitis Optica

34. Papilledema vs papillitis The main difference between papilledema and papillitis is Visual equity and optic nerve function Papilledema: Intact Papillitis : Impaired

35. points Papilledema Papillitis Definition Disc swelling due to Raised ICP Disc swelling due to Inflammation Laterality Bilateral Usually Unilateral Vision Transient obscuration of vision Sudden, persistent dimness of vision Pain none During ocular movement Etiology Raised ICP due to ICSOL,IIH,SSST etc. MS, NMO, Syphilis, Sarcoidosis etc. Visual acuity intact reduced Visual field Enlarge blind spot /tunnel vision Central or paracentral scotoma to complete blindness Fundoscopy Disc swelling with hemorrhage ;exudate Disc swelling without hemorrhage ;exudate Color vision Intact Impaired Light Reflex Normal( RAPD absent ) Relative afferent pupillary defect( RAPD present )

36. Pseudopapilledema Congenital or aquired anomalies of optic Disc Includes: Drusen, Hypermetropia, Myelinated nerve This term is reserved for condition condition not disease states.

37. Anterior ischemic optic neuropathy ( AION ) I schemic optic neuropathy, at the optic nerve head AION is traditionally divided into Arteritic (AAION) and Non- arteritic (NAION) Arteritic AION ( AAION ) usually associated with GCA; comprises only 10% to 15% of all AION Early differentiation of AAION and NAION is critical for medical management. AAION is a true medical emergency because GCA can cause imminent ischemic damage to the fellow optic nerve, retina, brain, and heart .

38. AION : Pathophysiology

39. AION: Altitudinal vision Loss Superior segmental Disc pallor corresponding to Inferior, Altitudinal field of vision defect on visual field test

40. Points Arteritic AION (AAION ) Non- arterictic AION (NAION) sex Female> Male Male=Female Age(y) >60 40-60 onset Acute Sub-acute, insidious Visual Loss Profound Less profound Second Eye involvement Within days to weeks Weeks to months Associated symptoms Headache,Jaw claudication, scalp tendeness absent Underlying disease Giant cell arteritis DM, HTN, Dyslipidemia Disc Pallor> Hyperemia Hyperemia > pallor ESR >90 <40 CRP raised normal Response to steroid Responsive Non-responsive Prognosis Untreated visual loss upto50-95%, 95% cases fellow eye involvement Spontaneous improvement up to 43% cases;<30% cases involvement of fellow eye

41. Arteritic -AION vs Nonarteritic -AION Suoirior and inferior margin obscures Pale disc( arteritic -AION) Flame shape hemorrhage Hyperemic Disc( Nonarteritic -AION)

42. Treatment approach to AION(due to GCA) Koster , M.J., Warrington, K.J. and Kermani , T.A., 2016. Update on the epidemiology and treatment of giant cell arteritis.  Current Treatment Options in Rheumatology ,  2 (2), pp.138-152.

43. AION vs Optic neuritis Why do we need to differentiate? Similarities in presentation: Unilateral dimness of vision Painful optic neuropathy Optic nerve dysfunction: field, acuity,color vision,RAPD,Optic disc swelling May Respond to steroids

44. Points Optic Neuritis AION Age of onset 20-30 >60 Pain 92% cases, exacerbate on eye movement Periorbital but no change with eye movement Associated Sensory disturbance, Limb weakness, Ataxia, Bowel bladder dysfunction, Headache,Jaw claudication, scalp tendeness onset Insidious ,progresses of hours to days Sudden onset, often notice upon awekenig Disc swelling Present only one third of the cases, in rest its retrobulbar Present in most of the cases Field defect Central scotoma Altitudinal MRI Enhancement of optic nerve No enhancement of optic nerve Recovery Within 2-4 weeks Over months prognosis Good prognosis poor

45. Leber’s Heriditary optic neuropathy(LHON) Mitocondrial disease Bilateral involvement of optic nerve May occur at any age Acute phase present with optic disc swelling and hyperemia Ultimately patient develops optic atrophy Associated with cardiac conduction defects, Tremor, limb weakness(LHON plus)

46. Leber’s Heriditary optic neuropathy(LHON) Blilateral hyperemic disc swelling Central scotomas; Right>left

47. Hypertensive retinopathy

48. Treatment It’s medical emergency Must be managed promptly and adequately to prevent further target organ damage. [AHA guideline,2017]

49. Diabetic Papillopathy Benign Optic disc swelling , t ypically bilateral Young juvenile diabetics No or minimal effects on visual acuity and visual fields are typically restricted. Usually occur in the absence of diabetic retinopathy 36% of cases of diabetic papillopathy progressing to NAION . Usually a diagnosis of exclution Spontaneous resolution within 2-10 months without any optic atrophy The exact pathogenesis is unclear, but is believed to occur due to disruption of the peripapillary vasculature Wallace, I.R., Mulholland, D.A. and Lindsay, J.R., 2012. Diabetic papillopathy : an uncommon cause of bilateral optic disc swelling.  QJM: An International Journal of Medicine ,  105 (6), pp.583-584.

50. Diabetic Papillopathy ( A  and  B ) Bilateral marked swelling and superficial flame haemorrhages in the left eye. Note, absence of significant diabetic retinopathy. ( C  and  D ) Swelling gradually resolving without atrophy 3 months later. Treatment: Good glycemic control regular intervals with close monitoring.

51. CRVO Papilledema ;Flame shape hemorrgahe in all qudrants Macular hemorrhage Setting sun Appearance

52. CRVO Pathogenesis Examination finding Visual acuity : impaired RAPD : present Treatment: Intra- vitreal injection :1 st line: VEGF inhibitor, reduce macular edema Intra- vitreal injection: 2 nd line,triamsinolone,dexamethasone Neovascularization: PRP

53. IIH Idiopathic intracranial hypertension is characterised by signs and symptoms of raised intracranial pressure (ICP) with no established pathogenesis. predominantly affects young, obese women Pathogenesis has not been fully elucidated Three main proposed mechanism increased venous sinus pressure, decreased CSF drainage across the arachnoid granulations or lymphatics enhanced CSF production at the choroid plexus

54. Pathogenesis

55. Neuroimaging :IIH T1 - MRI; sagittal; empty Sella turcica (arrow) presents in 70% of patients with idiopathic intracranial hypertension. T2 weighted MRI; axial; distension of the optic nerve sheath (arrows) has been reported in 45% of patients with the disorder.28 MRI venography; posterior view; hypoplastic right transverse sinus (arrow). (D) T2 weighted MRI; axial; flattening of posterior globes (arrows) can be seen in 80% of patients.

56. Fundal photographs with corresponding spectral domain optical coherence tomography(OCT) Fundal photographs and optical coherence tomography can be used for the diagnosis of papilledema. (A) Fundal photograph and (B) corresponding optical coherence tomography (healthy control). (C) Fundal photograph of papilloedema with an elevated disc and peripapillary halo, (D) corresponding OCT showing an increase in retinal nerve fibre layer thickness in IIH

57. Progression of visual field defect in IIH

58. Diagnostic criteria for adult idiopathic intracranial hypertension

59. Cerebral venous sinus thrombosis CSF drains into Intracranial venous sinuses CSF passively resorbrd into arachanoid granulations ,mostly withi supiriror sagittal sinus Incase of venous thrombosis CSF resorption decreased andvthe CSF pressure increases This raised ICP may ultimately give rise to papilledema

60. NCCT -head : Cord sign Contrast CT –head : Empty Delta sign

61. Figure : Sagittal sinus thrombosis. MR venogram showing absent venous flow signal in the middle third of the superior sagittal sinus (white arrows) (B) Axial gadolinium-enhanced T1-weighted MR scan showing an irregular filling defect of the superior sagittal sinus (white arrow) (C) Sagittal gadolinium-enhanced T1-weighted MR scan also showing a focal filling defect indicating thrombus (white arrow) (D) Axial susceptibility-weighted imaging showing low signal indicating blood products (thrombus) in the superior sagittal sinus (white arrow)

62. Treatment Should be started as soon as the diagnosis of CVT is clearly confirmed - Rapid anticoagulant therapy - Treatment of underlying cause ( eg , dehydration, sepsis, stopping any prothrombotic medications) - Control of seizures - Management of intracranial hypertension if required.

63. Compresive Optic neuropathy Lesion may compress or infiltrate the intraorbital , intracranial or prechiasmal optic nerve Large and intraorbital lesions often produce optic disc swelling Presentation Progressive unilateral optic neuropathy Usually no pain with eye movement Headache occurs if raised ICP or involvement of Trigeminal nerve Proptosis is common in orbital lesion Cranial nerve palsys occur if lesion extending to orbital apex, superior orbital fissure or cavernous sinus. Early disc change: Swelling ; Late change : Optic Atrophy

64. O ptic sheath meningioma Graves Opthalmopathy ,T1-w MRI reveals an contrast enhancing mass surrounding the optic nerve.( R ed Arrow) T1WI:Bilateral Fusiform enlargement of medial rectus ;Right compressing the optic nerve

65. Toxin induced neuropathy/ Toxic amblyopia Patient presents with sudden vison loss Abrupt onset central/ cecocentral scotoma Associated nausea, vomiting, abdominal pain Metabolic acidosis is one of the hallmark Initially optic disc is swollen but eventually patient develops optic atrophy Treatment: Lavage IV NaHCO 3 Antidote: Ethanol, fomepizole Others: Folinic acid Hemodialysis III IV

66. Toxin induce neuropathy( Methanol) Bilateral optic atrophy Visual field defects

67. Terminology Optic Disc: Intraocular part of optic nerve lies anterior to lamina cribrosa Papilla : slight elevation at periphery of optic disc Physiological Cup: Depression at optic disc

68. Take home message Papilledema must be differentiated from Pseudopapilledema cause true papilledema needs extensive workup and specific treatment but pseudopapilledema doesn’t. Not all bilateral optic disc swellings are papilledema e.g,NMO,anti-MOG,Toxic amblyopia, Diabetic papillopathy etc. Optic neuritis and AION both may present with painful visual loss but should be differentiated early specific management and better prognosis. Early differentiation of AAION and NAION is critical for medical management Though IIH is called idiopathic there are multiple proposed mechanism for its pathogenesis Diabetic and hypertensive patient both can present with Bilateral optic disc swelling. In hypertension it’s a medical emergency but in diabetic papillopathy it self limiting.

69. Thank You ……..