Craig Blackwell, MD

Santa Cruz, CA
Diplomate: American Board of Ophthalmology
Fellow: American Academy of Ophthalmology

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An Ophthalmology Practice in Santa Cruz, CA

Migraine Observations by C Miller Fisher

C Miller Fisher’s Migraine Rules

This is from an old but venerable paper by renowned neurologist Dr. CM Fisher from Massachusetts General Hospital. He was reporting on two series of patients (total N=205) looking for features that could help distinguish migraine symptoms from TIA or stroke and came up with the following guidelines.

The Rules:

  1. The presence of visual symptoms – scintillating scotoma, etc., provides an important clue.
  2. A gradual “build-up,” expansion and migration of the scintillating display, a phenomenon which does not occur in cerebrovascular disease (CVD).
  3. A “march” of paresthesias, a feature which does not occur in CVD.
  4. The serial progression from one accompaniment to another, for example, from visual to paresthesias to dysphasia, a course that does not occur in CVD.
  5. The occurrence of 2 or more identical spells, an event that helps to exclude embolism.
  6. Headache in association with the spell (50% of cases).
  7. A duration of the episode in the range of 15 to 25 minutes whereas 90% of TIAs associated with carotid or basilar artery disease last less than 15 minutes.
  8. The occurrence of a “flurry” of accompaniments, generally in the 50-60 year old age group is in keeping with our experience.
  9. A generally benign course without permanent sequelae.
  10. Exclusion of cerebral thrombosis, embolism, dissection, subclavian steal, epilepsy, thrombocythemia, polycythemia, hyperviscosity syndromes, and lupus.
  11. Normal angiography. This excludes thrombosis of arteries greater than 1.5 mm in diameter.
  12. Recurrence of essentially identical spells over a period of 5 to 10 years.

More Observations on 205 Cases

Duration of Migraine Episodes



< 5 min


6 to 30 min


½ to 1 hour


1 to 4 hours


5 to 24 hours


Classification of Symptoms

Among the different types of visual symptoms were:

  • Scintillating Scotomas
  • Loss of Vision: Total and Half Field Loss each eye
  • Blurred Vision

Other Symptoms Accompanying Vision Symptoms

  • Vision and Paresthesias (tingling, pins-and-needles, numbness)
  • Vision, Paresthesia and Speech Disturbance
  • Vision, Paresthesia, Speech and Paresis (weakness or paralysis)

Other Symptoms without Vision Symptoms

  • Paresthesia, Speech Disturbance and or Paresis

From: Stroke 1986; 17:5: 1033


The advance of different symptom types follows the organization of the brain. Vision function is located in the back end of the brain. Sensation behind the center fold and motor in front of the center fold. So as the spreading cortical depression expands forward on the surface of the brain it affects different systems, just like moving across the US from one state to another.

CBlackwell Sep2008