Amaurosis fugax

From WikiProjectMed
Jump to navigation Jump to search
Amaurosis fugax
The arteries of the choroid and iris. The greater part of the sclera has been removed.
SymptomsTemporary fleeting of vision in one or both eyes
DurationSeconds to hours

Amaurosis fugax (Greek amaurosis meaning darkening, dark, or obscure, Latin fugax meaning fleeting) is a painless temporary loss of vision in one or both eyes.[3]

Signs and symptoms

The experience of amaurosis fugax is classically described as a temporary loss of vision in one or both eyes that appears as a "black curtain coming down vertically into the field of vision in one eye;" however, this altitudinal visual loss is relatively uncommon. In one study, only 23.8 percent of patients with transient monocular vision loss experienced the classic "curtain" or "shade" descending over their vision.[4] Other descriptions of this experience include a monocular blindness, dimming, fogging, or blurring.[5] Total or sectorial vision loss typically lasts only a few seconds, but may last minutes or even hours. Duration depends on the cause of the vision loss. Obscured vision due to papilledema may last only seconds, while a severely atherosclerotic carotid artery may be associated with a duration of one to ten minutes.[6] Certainly, additional symptoms may be present with the amaurosis fugax, and those findings will depend on the cause of the transient monocular vision loss.[citation needed]


Prior to 1990, amaurosis fugax could, "clinically, be divided into four identifiable symptom complexes, each with its underlying pathoetiology: embolic, hypoperfusion, angiospasm, and unknown".[7] In 1990, the causes of amaurosis fugax were better refined by the Amaurosis Fugax Study Group, which has defined five distinct classes of transient monocular blindness based on their supposed cause: embolic, hemodynamic, ocular, neurologic, and idiopathic (or "no cause identified").[8] Concerning the pathology underlying these causes (except idiopathic), "some of the more frequent causes include atheromatous disease of the internal carotid or ophthalmic artery, vasospasm, optic neuropathies, giant cell arteritis, angle-closure glaucoma, increased intracranial pressure, orbital compressive disease, a steal phenomenon, and blood hyperviscosity or hypercoagulability."[9]

Embolic and hemodynamic origin

With respect to embolic and hemodynamic causes, this transient monocular visual loss ultimately occurs due to a temporary reduction in retinal artery, ophthalmic artery, or ciliary artery blood flow, leading to a decrease in retinal circulation which, in turn, causes retinal hypoxia.[10] While, most commonly, emboli causing amaurosis fugax are described as coming from an atherosclerotic carotid artery, any emboli arising from vasculature preceding the retinal artery, ophthalmic artery, or ciliary arteries may cause this transient monocular blindness.

Ocular origin

Ocular causes include:

Neurologic origin

Neurological causes include:

  • Optic neuritis[8]
  • Compressive optic neuropathies[8][29]
  • Papilledema: "The underlying mechanism for visual obscurations in all of these patients appear to be transient ischemia of the optic nerve head consequent to increased tissue pressure. Axonal swelling, intraneural masses, and increased influx of interstitial fluid may all contribute to increases in tissue pressure in the optic nerve head. The consequent reduction in perfusion pressure renders the small, low-pressure vessels that supply the optic nerve head vulnerable to compromise. Brief fluctuations in intracranial or systemic blood pressure may then result in transient loss of function in the eyes."[37] Generally, this transient visual loss is also associated with a headache and optic disk swelling.
  • Multiple sclerosis can cause amaurosis fugax due to a unilateral conduction block, which is a result of demyelination and inflammation of the optic nerve, and "...possibly by defects in synaptic transmission and putative circulating blocking factors."[38]
  • Migraine[39][40][41][42][43][44][45][46] (auras often involve temporary scotomas, and a spectrum up to transient full vision loss exists)
  • Idiopathic Intracranial Hypertension[47]
  • Intracranial tumor[47]
  • Psychogenic[24]


Amaurosis fugax associated with vascular defect, Location of atherosclerotic plaque arrow

Despite the temporary nature of the vision loss, those experiencing amaurosis fugax are usually advised to consult a physician immediately as it is a symptom that may herald serious vascular events, including stroke.[1][2] Restated, “because of the brief interval between the transient event and a stroke or blindness from temporal arteritis, the workup for transient monocular blindness should be undertaken without delay.” If the patient has no history of giant cell arteritis, the probability of vision preservation is high; however, the chance of a stroke reaches that for a hemispheric TIA. Therefore, investigation of cardiac disease is justified.[8]

A diagnostic evaluation should begin with the patient's history, followed by a physical exam, with particular importance being paid to the ophthalmic examination with regards to signs of ocular ischemia. When investigating amaurosis fugax, an ophthalmologic consultation is absolutely warranted if available. Several concomitant laboratory tests should also be ordered to investigate some of the more common, systemic causes listed above, including a complete blood count, erythrocyte sedimentation rate, lipid panel, and blood glucose level. If a particular cause is suspected based on the history and physical, additional relevant labs should be ordered.[8]

If laboratory tests are abnormal, a systemic disease process is likely, and, if the ophthalmologic examination is abnormal, ocular disease is likely. However, in the event that both of these routes of investigation yield normal findings or an inadequate explanation, noninvasive duplex ultrasound studies are recommended to identify carotid artery disease. Most episodes of amaurosis fugax are the result of stenosis of the ipsilateral carotid artery.[48] With that being the case, researchers investigated how best to evaluate these episodes of vision loss, and concluded that for patients ranging from 36–74 years old, "...carotid artery duplex scanning should be this investigation is more likely to provide useful information than an extensive cardiac screening (ECG, Holter 24-hour monitoring, and precordial echocardiography)."[48] Additionally, concomitant head CT or MRI imaging is also recommended to investigate the presence of a “clinically silent cerebral embolism.”[8]

If the results of the ultrasound and intracranial imaging are normal, “renewed diagnostic efforts may be made,” during which fluorescein angiography is an appropriate consideration. However, carotid angiography is not advisable in the presence of a normal ultrasound and CT.[49]


If the diagnostic workup reveals a systemic disease process, directed therapies to treat that underlying cause should be initiated. If the amaurosis fugax is caused by an atherosclerotic lesion, aspirin is indicated, and a carotid endarterectomy considered based on the location and grade of the stenosis. Generally, if the carotid artery is still patent, the greater the stenosis, the greater the indication for endarterectomy. "Amaurosis fugax appears to be a particularly favorable indication for carotid endarterectomy. Left untreated, this event carries a high risk of stroke; after carotid endarterectomy, which has a low operative risk, there is a very low postoperative stroke rate."[50] However, the rate of subsequent stroke after amaurosis is significantly less than after a hemispheric TIA, therefore there remains debate as to the precise indications for which a carotid endarterectomy should be performed. If the full diagnostic workup is completely normal, patient observation is recommended.[8]

See also


  1. 1.0 1.1 Benavente O, Eliasziw M, Streifler JY, Fox AJ, Barnett HJ, Meldrum H (October 2001). "Prognosis after transient monocular blindness associated with carotid-artery stenosis". N. Engl. J. Med. 345 (15): 1084–90. doi:10.1056/NEJMoa002994. PMID 11596587.
  2. 2.0 2.1 Rothwell PM, Warlow CP (March 2005). "Timing of TIAs preceding stroke: time window for prevention is very short". Neurology. 64 (5): 817–20. doi:10.1212/01.WNL.0000152985.32732.EE. PMID 15753415. S2CID 19550244.
  3. Fisher CM (December 1989). "'Transient monocular blindness' versus 'amaurosis fugax'". Neurology. 39 (12): 1622–4. doi:10.1212/wnl.39.12.1622. PMID 2685658. S2CID 13315378.
  4. North American Symptomatic Carotid Endarterectomy Trial Collaborators; Barnett HJM; Taylor, D. W.; Haynes, R. B.; Sackett, D. L.; Peerless, S. J.; Ferguson, G. G.; Fox, A. J.; Rankin, R. N.; Hachinski, V. C.; Wiebers, D. O.; Eliasziw, M. (August 1991). "Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. North American Symptomatic Carotid Endarterectomy Trial Collaborators". N. Engl. J. Med. 325 (7): 445–53. doi:10.1056/NEJM199108153250701. PMID 1852179.
  5. Lord RS (August 1990). "Transient monocular blindness". Australian and New Zealand Journal of Ophthalmology. 18 (3): 299–305. doi:10.1111/j.1442-9071.1990.tb00624.x. PMID 2261177.
  6. Donders RC; Dutch Tmb Study Group (August 2001). "Clinical features of transient monocular blindness and the likelihood of atherosclerotic lesions of the internal carotid artery". J. Neurol. Neurosurg. Psychiatry. 71 (2): 247–9. doi:10.1136/jnnp.71.2.247. PMC 1737502. PMID 11459904.
  7. Burde RM (September 1989). "Amaurosis fugax. An overview". J Clin Neuroophthalmol. 9 (3): 185–9. PMID 2529279.
  8. 8.0 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 "Current management of amaurosis fugax. The Amaurosis Fugax Study Group". Stroke. 21 (2): 201–8. February 1990. doi:10.1161/01.STR.21.2.201. PMID 2406992.
  9. Newman NJ. (1998). "Cerebrovascular disease". In Hoyt, William Graves; Miller, Neil; Newman, Nancy J.; Walsh, Frank (eds.). Walsh and Hoyt's Clinical Neuro-Ophthalmology. Vol. 3 (5th ed.). Baltimore: Williams & Wilkins. pp. 3420–6. ISBN 0-683-30232-9.
  10. 10.0 10.1 Jehn A, Frank Dettwiler B, Fleischhauer J, Sturzenegger M, Mojon DS (February 2002). "Exercise-induced vasospastic amaurosis fugax". Arch. Ophthalmol. 120 (2): 220–2. doi:10.1001/archopht.120.2.220 (inactive 31 October 2021). PMID 11831932. Archived from the original on 2007-09-29. Retrieved 2007-03-26.{{cite journal}}: CS1 maint: DOI inactive as of October 2021 (link)
  11. Braat A, Hoogland PH, DeVries AC, de Mol VanOtterloo JC (2001). "Amaurosis Fugax and Stenosis of the Ophthalmic Artery". Vasc Endovascular Surg. 35 (2): 141–2. doi:10.1177/153857440103500210. PMID 11668383. S2CID 38943888.
  12. Kaiboriboon K, Piriyawat P, Selhorst JB (May 2001). "Light-induced amaurosis fugax". Am. J. Ophthalmol. 131 (5): 674–6. doi:10.1016/S0002-9394(00)00874-6. PMID 11336956.
  13. Furlan AJ, Whisnant JP, Kearns TP (November 1979). "Unilateral visual loss in bright light. An unusual symptom of carotid artery occlusive disease". Arch. Neurol. 36 (11): 675–6. doi:10.1001/archneur.1979.00500470045007. PMID 508123.
  14. Fisher M (1952). "Transient monocular blindness associated with hemiplegia". Arch. Ophthalmol. 47 (2): 167–203. doi:10.1001/archopht.1952.01700030174005. PMID 14894017.
  15. Ellenberger C, Epstein AD (June 1986). "Ocular complications of atherosclerosis: what do they mean?". Semin Neurol. 6 (2): 185–93. doi:10.1055/s-2008-1041462. PMID 3332423.
  16. 16.0 16.1 Burger SK, Saul RF, Selhorst JB, Thurston SE (September 1991). "Transient monocular blindness caused by vasospasm". N. Engl. J. Med. 325 (12): 870–3. doi:10.1056/NEJM199109193251207. PMID 1875972.
  17. Imes RK, Hoyt WF (1989). "Exercise-induced transient visual events in young healthy adults". J Clin Neuroophthalmol. 9 (3): 178–80. PMID 2529277.
  18. Hayreh SS, Podhajsky PA, Zimmerman B (April 1998). "Occult giant cell arteritis: ocular manifestations". Am. J. Ophthalmol. 125 (4): 521–6. doi:10.1016/S0002-9394(99)80193-7. PMID 9559738.
  19. Goodman BW (November 1979). "Temporal arteritis". Am. J. Med. 67 (5): 839–52. doi:10.1016/0002-9343(79)90744-7. PMID 389046.
  20. Giorgi D, David V, Afeltra A, Gabrieli CB (March 2001). "Transient visual symptoms in systemic lupus erythematosus and antiphospholipid syndrome". Ocul. Immunol. Inflamm. 9 (1): 49–57. doi:10.1076/ocii. PMID 11262668. S2CID 35161683.
  21. Gold D, Feiner L, Henkind P (September 1977). "Retinal arterial occlusive disease in systemic lupus erythematosus". Arch. Ophthalmol. 95 (9): 1580–5. doi:10.1001/archopht.1977.04450090102008. PMID 901267.
  22. Newman NM, Hoyt WF, Spencer WH (May 1974). "Macula-sparing monocular blackouts. Clinical and pathologic investigations of intermittent choroidal vascular insufficiency in a case of periarteritis nodosa". Arch. Ophthalmol. 91 (5): 367–70. doi:10.1001/archopht.1974.03900060379006. PMID 4150748.
  23. Schwartz ND, So YT, Hollander H, Allen S, Fye KH (1986). "Eosinophilic vasculitis leading to amaurosis fugax in a patient with acquired immunodeficiency syndrome". Arch. Intern. Med. 146 (10): 2059–60. doi:10.1001/archinte.146.10.2059. PMID 3767551.
  24. 24.0 24.1 24.2 24.3 24.4 Bacigalupi M (April 2006). "Amaurosis Fugax-A Clinical Review" (PDF). The Internet Journal of Allied Health Sciences and Practice. 4 (2): 1–6. Archived (PDF) from the original on 2015-05-28. Retrieved 2021-11-01.
  25. Berdel WE, Theiss W, Fink U, Rastetter J (March 1984). "Peripheral arterial occlusion and amaurosis fugax as the first manifestation of polycythemia vera. A case report". Blut. 48 (3): 177–80. doi:10.1007/BF00320341. PMID 6697006. S2CID 13588599.
  26. Mundall J, Quintero P, Von Kaulla KN, Harmon R, Austin J (March 1972). "Transient monocular blindness and increased platelet aggregability treated with aspirin. A case report". Neurology. 22 (3): 280–5. doi:10.1212/wnl.22.3.280. PMID 5062262. S2CID 552116.
  27. Smith DB, Ens GE (March 1987). "Protein C deficiency: a cause of amaurosis fugax?". J. Neurol. Neurosurg. Psychiatry. 50 (3): 361–2. doi:10.1136/jnnp.50.3.361. PMC 1031809. PMID 3559620.
  28. Digre KB, Durcan FJ, Branch DW, Jacobson DM, Varner MW, Baringer JR (March 1989). "Amaurosis fugax associated with antiphospholipid antibodies". Annals of Neurology. 25 (3): 228–32. doi:10.1002/ana.410250304. PMID 2729913. S2CID 28110036.
  29. 29.0 29.1 29.2 29.3 29.4 29.5 29.6 29.7 Corbett, James W.; Digre, Kathleen B. (2003). "Amaurosis Fugax and Not So Fugax—Vascular Disorders of the Eye" (PDF). Practical viewing of the optic disc. Oxford: Butterworth-Heinemann. pp. 269–344. ISBN 0-7506-7289-7. Archived from the original (PDF) on 2007-09-26. Retrieved 2021-11-01.
  30. Landi G, Calloni MV, Grazia Sabbadini M, Mannuccio Mannucci P, Candelise L (1983). "Recurrent ischemic attacks in two young adults with lupus anticoagulant". Stroke. 14 (3): 377–9. doi:10.1161/01.STR.14.3.377. PMID 6419415.
  31. Elias M, Eldor A (March 1984). "Thromboembolism in patients with the 'lupus'-type circulating anticoagulant". Arch. Intern. Med. 144 (3): 510–5. doi:10.1001/archinte.144.3.510. PMID 6367679.
  32. Hayreh SS, Servais GE, Virdi PS (January 1986). "Fundus lesions in malignant hypertension. V. Hypertensive optic neuropathy". Ophthalmology. 93 (1): 74–87. doi:10.1016/s0161-6420(86)33773-4. PMID 3951818.
  33. 33.0 33.1 Sørensen PN (August 1983). "Amaurosis fugax. A unselected material". Acta Ophthalmol (Copenh). 61 (4): 583–8. doi:10.1111/j.1755-3768.1983.tb04348.x. PMID 6637419. S2CID 221395995.
  34. Ravits J, Seybold ME (September 1984). "Transient monocular visual loss from narrow-angle glaucoma". Arch. Neurol. 41 (9): 991–3. doi:10.1001/archneur.1984.04050200097026. PMID 6477235.
  35. Brown GC, Shields JA (October 1981). "Amaurosis fugax secondary to presumed cavernous hemangioma of the orbit". Ann Ophthalmol. 13 (10): 1205–9. PMID 7316347.
  36. Wilkes SR, Trautmann JC, DeSanto LW, Campbell RJ (April 1979). "Osteoma: an unusual cause of amaurosis fugax". Mayo Clin. Proc. 54 (4): 258–60. PMID 423606.
  37. Sadun AA, Currie JN, Lessell S (October 1984). "Transient visual obscurations with elevated optic discs". Annals of Neurology. 16 (4): 489–94. doi:10.1002/ana.410160410. PMID 6497356. S2CID 2245543.
  38. Smith KJ, McDonald WI (October 1999). "The pathophysiology of multiple sclerosis: the mechanisms underlying the production of symptoms and the natural history of the disease". Philosophical Transactions of the Royal Society B. 354 (1390): 1649–73. doi:10.1098/rstb.1999.0510. PMC 1692682. PMID 10603618.
  39. Mattsson, Lundberg; Lundberg, PO (June 1999). "Characteristics and prevalence of transient visual disturbances indicative of migraine visual aura". Cephalalgia. 19 (5): 479–84. doi:10.1046/j.1468-2982.1999.019005479.x. PMID 10403062. S2CID 5961275.
  40. Cologno D, Torelli P, Manzoni GC (October 2002). "Transient visual disturbances during migraine without aura attacks". Headache. 42 (9): 930–3. doi:10.1046/j.1526-4610.2002.02216.x. PMID 12390623. S2CID 32304894.
  41. Connor RC (November 1962). "Complicated migraine. A study of permanent neurological and visual defects caused by migraine". Lancet. 2 (7265): 1072–5. doi:10.1016/s0140-6736(62)90782-1. PMID 14022628.
  42. Carroll D (April 1970). "Retinal migraine". Headache. 10 (1): 9–13. doi:10.1111/j.1526-4610.1970.hed1001009.x. PMID 5444866. S2CID 46246035.
  43. McDonald WI, Sanders MD (September 1971). "Migraine complicated by ischaemic papillopathy". Lancet. 2 (7723): 521–3. doi:10.1016/s0140-6736(71)90440-5. PMID 4105666.
  44. Wolter JR, Burchfield WJ (1971). "Ocular migraine in a young man resulting in unilateral transient blindness and retinal edema". Pediatr Ophthalmol. 8: 173–6.
  45. Kline LB, Kelly CL (September 1980). "Ocular migraine in a patient with cluster headaches". Headache. 20 (5): 253–7. doi:10.1111/j.1526-4610.1980.hed2005253.x. PMID 7451120. S2CID 29684052.
  46. Corbett JJ. (1983). "Neuro-ophthalmologic complications of migraine and cluster headaches". Neurol. Clin. 1 (4): 973–95. doi:10.1016/S0733-8619(18)31134-4. PMID 6390159.
  47. 47.0 47.1 Hedges TR (1984). "The terminology of transient visual loss due to vascular insufficiency". Stroke. 15 (5): 907–8. doi:10.1161/01.STR.15.5.907. PMID 6474546. S2CID 8664120.
  48. 48.0 48.1 Smit RL, Baarsma GS, Koudstaal PJ (1994). "The source of embolism in amaurosis fugax and retinal artery occlusion" (PDF). Int Ophthalmol. 18 (2): 83–6. doi:10.1007/BF00919244. PMID 7814205. S2CID 394747. Archived (PDF) from the original on 2008-12-17. Retrieved 2021-11-01.
  49. Walsh J, Markowitz I, Kerstein MD (August 1986). "Carotid endarterectomy for amaurosis fugax without angiography". Am. J. Surg. 152 (2): 172–4. doi:10.1016/0002-9610(86)90236-9. PMID 3526933.
  50. Bernstein EF, Dilley RB (October 1987). "Late results after carotid endarterectomy for amaurosis fugax". J. Vasc. Surg. 6 (4): 333–40. doi:10.1067/mva.1987.avs0060333. PMID 3656582.

External links

External resources