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VASCULAR NEURO-OPHTALMOLOGICAL
EMERGENCIES
Irene Davidescu, Sanda Nica
Neurology Department, “Carol Davila” University of Medicine and Pharmacy,
Bucharest, Romania
ABSTRACT
Neuro-ophtalmology is a borderline specialty, as the eye is not an isolated organ but an extension of the brain. A lot of diseases can
cause visual troubles and the vascular ones are quite frequent. The precocious evaluation of the visual function is essential for the
therapeutical approach and for the recovery, and all this process seldom needs involvment of a medical team.
The anterior ischemic optic neuropathy includes some pathogenic entities which determine the optic nerve ischemia, with a papilar
edema present acutely, painless and without any predicting signs. This disease is very often associated with giant cell arteritis, and
the non-arteritic one is the most frequent cause of vision loss in patients over 50 years. The main risk factors are hypertension,
diabetes and dyslipidemia. The antiagregant therapy remains essential. Retinal artery occlusion is the ocular equivalent of
cerebrovascular disease. The occlusion may be central, causing a loss of central vision in the affected eye, or in a branch of the
retinal artery, affecting only a part of the retina served by that branch retinal vessel and sparing central visual acuity. The main cause
is the carotidian stenosis and less the cardiac embolia. This is a medical emergency which can be approached with intra-arterial
trombolysis if the pacient comes within 100 minutes from the beginning. The transient ischemic attack with ocular implications is
manifested with a transitor monocular blindness (amaurosis fugax) and represents a medical emergency, as it could predict a
definitive stroke. The ethiology differs, depending on the patient’s age, in young ones it can be associated with migraine and the
antiphospholipid antibodies syndrome, and in the elderly the main mechanism is the atherosclerotic one.
Key words: neuro-ophtalmology, ischemic optic neuropathy, transient ischemic attack, migraine, antiphospholipid antibodies syndrome
CLASSIFICATION
appearance of a papilar edema, without painand other alarming signs.
A sudden visual loss can be uni or bilateral, seems that it is related to the presence of hypo- The most frequent causes of transient monocular tension, with the appearance of a watershed infarction between the central artery of the retina and the posterior ciliary arteries. The There are two types of anterior ischemic optic Retinian vasospasm or the retinian migraine – Specific arteriolar pathology, especially – Nonarteritic: associated with the process of atherosclerosis, representing the most The causes for transient bilateral visual loss are: in patients after 50 years. Approximately Microvascular lesions of the optic nerve (as 30% of these patients will present disorders in the other eye, especially those with hy- pertension, diabetes and hyperlipidemia.
CHARACTERISTICS
ANTERIOR ISCHEMIC OPTIC NEUROPATHY
The average age of onset is in the 7th decade ischemia (the proximal part to the globe), Smoking can determine appearance in younger with monocular visual loss, suddenly, and the ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VI, NO. 3, 2007
ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VI, NO. 3, 2007
There is no confirmation of association with oftalmic artery, the first intracranial branch carotidian stenosis, but there were not done studies on a significant number of patients The retinal artery occlusion is one of the most It can be associated with: migraine, nocturnal dramatic ophtalmological emergencies with arterial hypotension, polymialgia reumatica, increased intraocular pressure, cataract sur- The occlusion of the central retinal artery gery, and use of sildenafil (Viagra) and tadalafil represents over 50% of the occlusions of the retinal vessels, and the gravity of the event is There are no genetical factors discovered to depending of the vascular retinal type.
determine a predisposition to the appearance The occlusion of the retinal artery by platelet/ Studies of external and systemical factors sudden loss of the vision and represents the which influence the homocysteine levels sho- ocular equivalent of cerebrovascular disease.
wed that the levels of homocysteine are higher The occlusion can be total, affecting the among patients with anterior ischemic optic central vision in the affected eye or on one neuropathy, but we must not forget that the branch of the artery, causing a partial visual loss, with the integrity of the central acuity.
Clinical characteristics
mining the retinal tissue ischemia, resultingin acute retinal edema and death of retinal Visual acuity is decreased and varies from The prognostic is poor, in spite a lot of studies Color vision is affected proportionally with the visual acuity decreasing, as opposed to optic neuritis, in which color vision typically – The arterio-arterial emboli (after carotidian The visual field we observe an inferior altitu- stenosis-20 to 45% of the patients have hemo- dinal defect, but we can see all the types of dynamically significant stenosis, >60%), and We will see an edematous optic nerve head, – In younger ages, under 30 years, it is fre- and hemorrhage on the disc is also very fre- quently associated with: posttraumatic carotid dissection, hypercoagulable states, migrena, Biological inflammatory signs, especially in – The carotidian emboli are due to athero- The clinical outcome is generally favorable, matous ulcerations at the bifurcation, associa- only a small number of patients will have a ted with stenosis; the emboli can be formed severe diminution of visual acuity in the first of cholesterol, platelet/fibrin (causing TIAs- amaurosis fugax) or calcium (the most dan-gerous because they can cause irreversibile TREATMENT
– The cardiac emboli can be formed of calcium Addressed to the vascular risk factors enun- (like in valvular calcifications), infectious (en- docarditis), platelet/fibrin (after cardiac The antiagregants are essential, especially by preventing the reccurence in the other eye For giant cell arteritis, the corticotherapy in high doses and for at least 6 months is im- – Systemic vasculitis with periarteritis lesions portant in reducing the risk of reccurence at – Hemathological states: antiphospholipidic syndrome, Protein S and C deficiency,antithrombin lll deficiency) RETINAL ARTERY OCCLUSION
– Retinian migrena (an exclusion diagnosis)• The retinal vascularisation (the central retinal artery and the ciliary arteries) comes from the ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VI, NO. 3, 2007
– Most frequent in the 7th decade of life – The diagnosis is confirmed by angio-MRI – The visual acuity is affected in central vision Classification: depending on the risk of develo- and partial if one of the branches is occluded ping neoformation vessels due to the retinal ische- – The visual field examination shows different deficits, proportional with the extension of outcome is poor, with loss of vision, finally – At the fundus examination we can observe – The aim of the therapy is to reduce the outcome is benign, with recovery of vision, intraocular pression by topical or systemical almost complete (sometimes the only sequela – It can be used: intra-arterial thrombolysis (if Painless, unilateral sudden visual loss.
the patients comes in less than 100 minutes from the onset) or hyperbar oxigen (in the tions, retinian hemorrhages, papilar edema and neoformation vessels. This examinationis not able to differentiate the ischemic type OCCLUSION OF RETINAL ARTERY BRANCHES
from the non-ischemic one, nor precociousor late in the evolution of the disease.
Treatment: there are not yet discovered real affecting only branches of the retinal artery The most frequent arteries implied are the The outcome is better: the partial recovery Hemodilution when there is a viscous state The therapeutical approach is similar with theone in the total occlusion increases when the patients have diabetes Surgical treatment: laser-therapy for the non-ischemic type for inducing chorioretinian OPHTALMIC ARTERY OCCLUSION
Panretinian photocoagulation for preventing the appearance of neovascularisation in the retinal artery occlusion: atrial fibrillation,atrial mixoma, carotidian atherosclerosis with OCCLUSION OF RETINAL VEIN BRANCHES
Local factors: retrobulbar anesthesia, orbital affectation in the retinian vessels after the Vasospasm after a subarahnoidian hemorrhage Sudden loss of vision finally to blindness Risk factors: hypertension, cardiovascular The fundus examination shows pallor of the retina, and the fluorescein angiography points out retinian or choroidian perfussion deficits Clinical characteristics: visual loss in the CENTRAL RETINAL VEIN OCCLUSION
ROMANIAN JOURNAL OF NEUROLOGY – VOLUME VI, NO. 3, 2007
The fluorescein angiography shows colateral seconds to several minutes. This entity repre- and neoformation vessels, papilar edema, lack sents an emergency because it can predict a of cappilars vessels, serous retina detachments Treatment: photocoagulation (when the pa- pilar edema is present or the visual acuity is – In elderly people the mechanism is mainly atherosclerotic, associated with carotidian Outcome: depending on the extension of the lesions, the presence of papilar edema and – In younger people it is frequently associated with migrena, antiphospholipidic syndromeor posttraumatic carotidian dissection TRANSIENT ISCHEMIC ATTACK
methods, ecodoppler, biological risk factors onset and a duration between 2 and 15 mi- The ocular manifestation of a TIA is the ap- pearance of a transitor monocular blindness – Endovascular therapy: carotidian stent or REFERENCES
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