Ischemic optic neuropathy

Ischemic optic neuropathy (ION) is the loss of structure and function of a portion of the optic nerve due to obstruction of blood flow to the nerve (i.e. ischemia). Ischemic forms of optic neuropathy are typically classified as either anterior ischemic optic neuropathy or posterior ischemic optic neuropathy according to the part of the optic nerve that is affected. People affected will often complain of a loss of visual acuity and a visual field, the latter of which is usually in the superior or inferior field.[1]

Ischemic optic neuropathy
Optic nerve
SpecialtyOphthalmology 

When ION occurs in patients below the age of 50 years old, other causes should be considered. Such as juvenile diabetes mellitus, antiphospholipid antibody-associated clotting disorders, collagen-vascular disease, and migraines. Rarely, complications of intraocular surgery or acute blood loss may cause an ischemic event in the optic nerve.[2]

Presentation

Anterior ION presents with sudden, painless visual loss developing over hours to days.[3]

Diagnosis

Examination findings usually include decreased visual acuity, a visual field defect, color vision loss, a relative afferent pupillary defect, and a swollen optic nerve head. Posterior ION occurs arteritic, nonarteritic, and surgical settings. It is characterized by acute vision loss without initial disc edema, but with subsequent optic disc atrophy.[3]

Management

Although there is no recognized treatment that can reverse the visual loss. Upon recent reports, optic nerve health decompression may be beneficial for a select group of patients with a gradual decline in vision due to ION.[4]

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gollark: Not my code.
gollark: This literally says "pay attention to what you run", *but actually warns you twice*.
gollark: ```lua --Error screen term.clear() term.setCursorPos(1,1) print("ERROR!!!") sleep(0.1) print("ERROR CODE: ERR_OS_CORRUPT") sleep(0.1) print("Detailed information for diagnostics follow:") sleep(0.1) print("0x00000001 0x00000002 0x00000010") sleep(0.1) print("0x00000101 0x00120000 0x01000300") sleep(0.1) print("0x00000000 0x00001040 0x0000000F") sleep(0.1) print("0x00010506 0x01200040 0x00000003") sleep(0.1) term.setCursorPos(1,10) sleep(0.3) print("If you installed any new hardware or software,") sleep(0.1) print("try removing them before restarting.") sleep(0.1) print("If the problem still persists, bring your computer") sleep(0.1) print("to a technician.") sleep(0.2) print("Error program left a message: Pay attention to what you run next time ;)") sleep(0.1) term.setCursorPos(1,17) sleep(0.3) print("You will lose all unsaved work.") sleep(2) print("This computer has been terminated.")```

See also

References
  1. editor, Cynthia A. Bradford, executive (2004). Basic ophthalmology (8th ed.). San Francisco: American Academy of Ophthalmology. pp. Chapter 2. ISBN 1560553618.CS1 maint: extra text: authors list (link)
  2. Oria, Veronica. "Ischemic Optic Neuropathy: Abstract." Seminars in Neurology. By Monica Rodriguez Fontal, John B. Kerrison, and Reinaldo Garcia. N.p.: Thieme, 2007. N. pag. Print.
  3. "Chapter 7: Ischemic Optic Neuropathy." Walsh and Hoyt's Clinical Neuro-ophthalmology. Ed. Neil R. Miller, Frank Burton Walsh, and William Fletcher Hoyt. Illustrated ed. Vol. 1. N.p.: Lippincott Williams & Wilkins, 2005. N. pag. Print.
  4. Oria, Veronica. "Ischemic Optic Neuropathy: Abstract." Seminars in Neurology. By Monica Rodriguez Fontal, John B. Kerrison, and Reinaldo Garcia. N.p.: Thieme, 2007. N. pag. Print.
  • Dictionary of Eye Terminology, Triad Publishing Company, 1990.
Classification


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