Ischemic Optic Neuropathy

Ischemic Optic NeuropathyOphthalmology & Neuro-ophthalmology Dr. Omer Y. Bialer

1DisclosureNo conflict of interestsI have nothing to disclose

ION = Ischemic Optic Neuropathy2Presentations outlineIntroduction Terminology and NosologyNonarteritic anterior ischemic optic neuropathyArteritic IONPerioperative IONRadiation optic neuropathyTake home massage summary

3 SUMMARY

3Introduction ION is the most common acute optic neuropathy > age 502nd most common optic neuropathy after glaucomaRelatively common neuro-ophthalmological disorderVisual loss is often severeNo effective treatment or prevention

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IntroductionION is due to:poor blood flow to the optic nerve Acute occlusion of the feeding arteriesShort posterior ciliary arteriesOphthalmic artery5Terminology & Nosology IONNonarteritic Anterior ION (NAION)with swollen optic discNonarteritic Posterior ION (NA-PION) with normal optic discArteritic ION (vasculitis)Nonarteritic ION (cardiovascular risk factors)Arteritic Posterior ION (APION) with normal optic discArteritic Anterior ION (AAION)with swollen optic disc

66Terminology & Nosology IONNonarteritic Anterior ION (NAION)with swollen optic discNonarteritic Posterior ION (NA-PION) with normal optic discArteritic ION (vasculitis)Nonarteritic ION (cardiovascular risk factors)Arteritic Posterior ION (APION) with normal optic discArteritic Anterior ION (AAION)with swollen optic disc7Idiopathic IONRadiation optic neuropathyPerioperative IONGCAOther vasculitides ION ""7NAION(Nonarteritic Anterior Ischemic Optic Neuropathy)

8NAION is the most common ION~ 90% of IONIncidence: 1 / 10,000 / year (> 50 y.o) 0.5/ 100,000 / year (overall)Mean age at onset 57-65Presentation: acute painless monocularvisual field loss visual acuity loss

9Non arteritic posterior ischemic optic neuropathy is exceedingly rare and is a diagnosis of exclusion. 9

The most important risk factor is a crowded optic discdisc at risk = small optic disc + minimal cup

crowdednormalglaucoma10More risk factors for NAIONHypertension (50%)Diabetes mellitus (25%)Obstructive sleep apnea (55%)HyperlipidemiaIschemic heart diseaseObesityTobacco useHigh intraocular pressure

11 OSA NAION .11Several meds are associated with NAIONErectile dysfunction drugs Amiodarone VasoconstrictorsCocaine

12(e.g. Viagra, Cialis)(e.g. nasal decongestants)The pathogenesis of NAION differs from IHD or CVAdecrease in blood flowEdema of optic discBlockage of axonal flowCompression of axons and blood vesselsNecrosis and demyelination of nerve fibersCardiovascular risk factorsCrowded optic disc13Eye Examvisual acuity & color vision can be normalA relative afferent pupillary defectNormal anterior segmentOptic disc edemaCrowded optic disc (fellow eye)

Peripapillary hemorrhagesNerve fiber layer edemaObscured borders14The most common visual field defect is a superior or inferior scotoma

Inferior altitudinal defect

Superior arcuate defect

Combined superior & inferior defect15NAION is a clinical diagnosisElderly patient +/- cardiovascular risk factorsAcute painless optic neuropathy + disc edema + crowded optic disc in fellow eye Rule out arteritic AION Do Humphrey visual fields Imaging is not in indicatedFrequent follow-up16 OSA (BERLIN QUESTIONNARE) 16There is no proven treatment for NAIONIONDT = ION decompression trialA multicenter randomized controlled clinical trialno efficacy for optic nerve fenestrationIntravitreal steroids (triamcinolone acetate)Intravenous noradrenalineWarfarin TPALevodopa + carbidopa 17There is no proven treatment for NAIONOral prednisone 40-60mg daily may hasten resolution of disc edema

Some evidence for anti-VEGF intravitreal injections

18ProphylaxisControl of cardio-vascular risk factors

Aspirin 100 mg daily limited evidence for second eye prophylaxis

19Disc edema resolves in 1 month

Optic atrophy

Optic atrophy with cuppingcup20Significant improvement is rare~40% experience partial improvementImprovement may take up to 6 months15% risk for fellow eye involvement in 2 years< 5 % recurrent AION (the same eye)A significant visual field defect persists21Arteritic IONAnd Giant Cell Arteritis (GCA) 22>50% of Arteritic ION are d/t Giant Cell ArteritisOther etiologies include:Systemic Lupus ErythematosusWegeners granulomatosisBehcets diseaseChurg StraussPolyarteritis Nodosa

23GCA* - key facts Large vessel vasculitisPredilection for the aortic arch Incidence 20 / 100,000 / year (> age 50) 20% of GCA patients experience severe visual lossAION is the most common ophthalmic manifestation of GCAA-AION is an ophthalmic emergency !* GCA = Giant Cell Arteritis (Temporal arteritis)24Arteritic ION presents like any ION, but . . .75% have typical systemic symptoms 30% have preceding transient visual loss

54% have visual acuity of count-fingers No light perception>50% second eye ION within hours -weeks 25(amaurosis fugax)(vs 26% in NAION)

There are specific funduscopic findings

The involved swollen optic disc is acutely paleNAION26There are specific funduscopic findings

Branch Retinal Artery OcclusionCentral Retinal Artery OcclusionCherry red spotIschemic retina27There are specific funduscopic findings Choroidal hypoperfusion indicates multifocal ischemia on Fluorescein angiography

normal choroidLack of choroidal perfusion28The workup of suspected Arteritic IONGCA Symptoms / signs ? Do blood tests butESR, CRP, Hb, PLT, FibrinogenUrgent TAB*TAB* in 1 wIv Solomedrol Prednisone + aspirinyesnoIV Solomedrol Prednisone + aspirinuntil biopsy resultshighnormalNAION* TAB = Temporal Artery Biopsy29 ESR CRP 97% 2 " , . 29Ophthalmic GCA should be treated with IV steroids Few studies evaluated treatment protocolsStudies in ophthalmology differ from rheumatology We recommend:IV methylprednisolone 1000mg/d for 3 days followed by a very slow taper of oral prednisone Aspirin 100mg dailyRheumatology consultation & follow-up

30Tocilizumab ( IL6) GCA30Perioperative ION(post operative AION and PION)31ION is a rare surgical complicationION is an uncommon but devastating complication after various types of surgeries

Intraocular surgeriesIntraocular injectionsNon-ocular surgeries

ION may also occur after:renal dialysiscardiac catheterization d/t Elevated intraocular pressure32ION may complicate non-ocular surgeriesThe 2 most classic are : CABGSpinal surgery Commonly bilateral There is often profound visual lossVisual loss may be immediate or delayed (days)

33(mostly AION, 0.06%)(mostly PION, 0.2%)The differential diagnosis of post-operative visual loss includesIschemic optic neuropathy

Retinal artery occlusion

Angle closure glaucoma34

Unresponsive mid-dilated pupilHazy corneaRed angry eyeCherry red spotThe differential diagnosis of post-operative visual loss includesCortical blindness

Corneal erosion35

EpithelialirregularityBilateral occipital stroke

CORNEAL EROSION PITUITARY APOPLEXY MRI35There is no prospective / controlled data regarding perioperative IONRisk factors:Obesity Male genderProlonged surgical timeSurgery in the prone positionLarge fluid shifts / severe blood loss

36There is no effective treatmentPrognosis is poor significant improvement in minority of patientsShould correct anemia, saturation & hypotension to improve perfusionNo evidence for efficacy of :AspirinAnti - coagulants ThrombolyticsAnti-glaucoma drops

3740 . saturation & "anti glaucoma drops"37RON(Radiation Optic Neuropathy)38RON is a late complicationPrevalence ~ 0.5% Mean interval 18 monthsThe optic nerves must be in the radiation field39(range: 3 months 9 years)

The risk factors are:Radiation dosage AgeDiabetes mellitusPresence of compressive optic neuropathyConcomitant chemotherapyPrevious radiotherapy Multiple sclerosis

40(>total 50 Gy or single dose > 10 Gy)RON mostly presents as PIONMay be monocular or binocular45% have visual acuity of no light perceptionDiagnosis is one of exclusion:Suspected Optic neuropathyPMH of radiotherapyNo other obvious explanationOptic nerve enhancement on MRI

41Isolated enhancement on MRI42

optic nerve enhancementT1W with fat suppression + gadolinium

There are few treatment optionsOral corticosteroids (prednisone 1mg/kg)Anticoagulants (heparin)AspirinHyperbaric oxygen (30-60min/day x 14-30 days)Intravenous Bevacizumab (2-4 cycles every 2 weeks)43

Suspected RON ?44Onset < 48-72 hours ?yesVEPBrain+orbits MRI with gadoliniumnormalabnormalHyperbaric oxygen Look for other etiologiesPO prednisone Consider IV Bevacizumab Enhancement ?yesOther optic neuropathynoVEP - . () , - 27 30-40 30-60 100% 2-3 . 48-72 .

44Prognosis of RON is poorSpontaneous recovery is rareTreatment is mostly ineffective85% visual acuity 20/200Optic atrophy appear in 6-8 weeksEnhancement on MRI resolves after several months

45Conclusions(the take home massage) 46ION is an ophthalmic emergencyPatients with GCA+ION are in danger of catastrophic, irreversible, bilateral blindness that may be prevented by prompt treatment with corticosteroidsAny patient > 50 presenting with ION an immediate workup to rule out GCA

47ION is not another type of CVAAlthough considered a stroke of the optic nerve and shares many risk factors with cerebrovascular disease, It cannot be directly compared to cerebral infarction, and therefore the evaluation should not be similar to that of cerebral infarction.

48Non arteritic anterior ischemic optic neuropathy is not an embolic disorder, but a small vessel disease. Evaluation of the internal carotid artery is not routinely indicated. There is also no definite increased risk of stroke in patients with nonarteritic anterior ischemic optic neuropathy, but vascular risk factors are common and should be controlled.48There is no effective treatment for IONthere are no class I studies showing benefit from any medical or surgical treatments49SteroidsAspirinAnti VEGFDecompression surgeryHyperbaric oxygenLevodopaErythropoietinNoradrenalinHeparinTPALimited efficacy for prophylaxisAspirin 100mg dailyControl of cardiovascular risk factorssuspect GCA !!!Avoid prolonged surgical time and dramatic shifts in body perfusion during surgrey Consider routine serial brain MRIs after brain radiotherapy to detect RON early50Thank you For listening51Acknowledgments Based on the chapter: Optic nerve: Ischemic.Bialer OY, Bruce BB, Biousse V, Newman NJ.Oxford textbook in Neuro-ophthalmologyOxford textbook in clinical neurologyEditor: Bremner F. Publisher: Oxford University PressGratitude to : Dr. Karin Mimoni Dr. Hadas Kalish-Stiebel Dr. Beau B. Bruce Dr. Nancy J. Newman Dr. Valrie Biousse52Visit my website to download the presentation: www.dr-bialer.com

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