Diagnosing Migraine

One of the difficulties encountered at times 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 4-72 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 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.
 

The more technical explanation:

In the ICHD-II, retinal migraine is described as,

Repeated attacks of monocular visual disturbance, including scintillations, scotomata or blindness, associated with migraine headache.

The diagnostic criteria for retinal migraine under ICHD-II are:

1. At least 2 attacks fulfilling criteria B and C

2. Fully reversible monocular positive and/or negative visual phenomena (e.g., scintillations, scotoma or blindness) confirmed by examination during an attack or (after proper instruction) by the patient’s drawing of a monocular field defect during an attack

3. Headache fulfilling criteria B–D for migraine without aura begins during the visual symptoms or follows them within 60 minutes

4. Normal ophthalmological examination between attacks

The relevant diagnostic criteria for migraine without aura are:

2. Headache attacks lasting 4–72 hours (untreated or unsuccessfully treated)

3. Headache has at least two of the following characteristics:

1. unilateral location

2. pulsating quality

3. moderate or severe pain intensity

4. aggravation by or causing avoidance of routine physical activity (e.g., walking or climbing stairs

4. During headache at least one of the following:

1. nausea and/or vomiting

2. photophobia and phonophobia
    

For more information:

• Anatomy of a Migraine
• Basilar-Type Migraine: What Is It?
• Medication Overuse Headache: When the Remedy Backfires
• Headache and Migraine Preventives: It's Impossible to Have Tried Everything!
• Quiz: Do you know the truth about Migraine?
• What is... Abdominal Migraine?
      

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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.

Published October 16, 2006
© Teri Robert