What Is Retinal Migraine?

Diagnosing migraine

One of the difficulties encountered when discussing migraines occurs when a migraineur is given a diagnosis that isn't actually accurate in diagnostic terms, but is really a descriptive term. Such terms may be used fairly frequently, but they fall short of a diagnosis and may also be used differently from one doctor to another. That's one reason why most doctors diagnose based in the International Headache Society's International Classification of Headache Disorders, 2nd Edition (ICHD-II). A "standard" diagnosis also makes communications and transitions easier when patients need to consult other doctors or change doctors.

There are several terms that are sometimes used, supposedly as migraine diagnoses, that involve visual symptoms. Most of them aren't actually standard migraine diagnoses. Retinal migraine, however, is an actual migraine diagnosis. What becomes confusing about it is that it's sometimes misused, resulting in a misdiagnosis. The term "retinal migraine" is often misused to mean any migraine that involves any visual symptoms, or a migraine with visual symptoms but without the headache phase of the attack.

Retinal migraine symptoms:

Retinal migraine is migraine where there are repeated attacks of visual disturbances preceding the headache phase of the migraine attacks.

A retinal migraine attack begins with monocular visual symptoms that can include:

1. scintillations
2. scotoma
3. temporary blindness.

The headache phase of a retinal migraine begins during or within 60 minutes of the visual symptoms. The headache phase presents symptoms consistent with migraine without aura:

• Headache duration of 4 to 72 hours
  
• At least two of these characteristics:

  1. unilateral location

  2. pulsatile quality

  3. moderate or severe pain intensity

  4. aggravation by or causing avoidance of routine physical activity such as walking or climbing stairs
  

• At least one of these characteristics:

  1. nausea and/or vomiting

  2. photophobia and phonophobia
  

The primary differentiating factors between retinal migraine and migraine with aura are:

1. The visual symptoms of retinal migraine are monocular.
2. Total, but temporary, monocular blindness may occur in retinal migraine.
   

Diagnosing retinal migraine:

There are no diagnostic tests to confirm migraine disease. Diagnosis is accomplished by reviewing the patient's personal and family medical history, studying their symptoms, and conducting an examination. Migraine is then diagnosed by ruling out other causes for the symptoms. With retinal migraine, it is essential that other causes of transient blindness be fully investigated and ruled out.

Treatment:

For infrequent attacks, medications used for other forms of migraine are often employed to relieve the other symptoms. These medications can include NSAIDs, antinausea medications, Midrin, ergotamines or the triptans. The choice of medications is somewhat affected by the age of the patient. When migraines are frequent, the same preventive therapies used for other migraines can be explored.

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Resources:

"The International Classification of Headache Disorders, 2nd Edition." Cephalalgia 24 (s1). doi: 10.1111/j. 1468-2982.2003.00824.x

Randolph W. Evans, Nina T. Mathew. "Handbook of Headache, Second Edition." Philadelphia: Lipincott Williams & Wilkins. 2005.

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Teri Robert, About.com's Headaches and Migraine Guide since 2000, is a nationally-known author and award-winning patient advocate. In addition to her work here, she is the Support Advisor for MAGNUM, the National Migraine Association, and serves on the education committee of O.U.C.H., the Organization for Understanding Cluster Headaches. To read more about Teri, read her full bio.