Causes and risk factors
The cause of arteritic AION is giant cell arteritis.
Nonarteritic AION can be caused by any of the several disease conditions such as diabetes, vasculitis, blood disorders, changes in blood pressure, and herpes zoster.
Clinical presentation
Ischemic optic neuropathy is of 2 types:
Anterior ischemic optic neuropathy – This refers to interruption of the blood flow in the anterior portion of the optic nerve.
Posterior ischemic optic neuropathy – This refers to interruption of the blood flow in the posterior portion of the optic nerve. Posterior ION is quite rare compared to anterior ION.
Anterior ischemic optic neuropathy (AION) is of 2 different types:
Arteritic AION – This condition is associated with giant cell arteritis. It occurs in the elderly, especially women.
Nonarteritic AION – This condition occurs in all ages and both genders.
Arteritic AION presents with symptoms of giant cell arteritis. These include pyrexia, weakness, and pain in the scalp, neck and jaw. The patient then experiences temporary blurring or loss of vision. The visual acuity is reduced. Hemorrhages are present around the optic disk.
In nonarteritic AION, typically the patient wakes up with a sudden loss of vision in one eye.
Investigations
A detailed ophthalmic examination will be carried out.
Fluorescein angiography is carried out to trace the blood flow of the optic nerve.
In order to determine the cause of AION, several blood tests are carried out such as C-reactive protein and ESR.
Imaging tests such as CT or MRI may be recommended.
Treatment
There is no specific treatment for ischemic optic neuropathy. Anti-inflammatory drugs such as corticosteroids may be prescribed. Treating the underlying cause is necessary.
When to contact a doctor
Contact a doctor as soon as you experience facial pain or blurring of vision.
Systems involved
Ophthalmic, CNS
Organs involved
Eyes, nerves
