Lifelong migraine aura without headache: change of pattern with upper respiratory infection

Changes in the features of migraine during a lifetime may offer clues to the pathogenesis.

CASE HISTORY

A retired professor of psychiatry (SIC) experienced migraine aura without headache from the age of 20, about once in 2 years. Without prodromal symptoms he suddenly became aware of not being able to see properly in the left visual field and had difficulty with reading. Within two minutes a bright light appeared, enlarged into three-quarters of a circle enclosed by zigzag scintillating lines coloured black with a golden edge surrounding a scotoma (Figure 1). The visual symptoms lasted about twenty minutes then gradually disappeared; he never experienced headache or gastrointestinal, visual or mental symptoms after his aura. He was unable to identify any precipitants for the visual disturbance, which could occur during reading or other activities.

Figure 1.

Scintillations surrounding scotoma drawn up to full development, at which they persisted for a further 10 minutes before gradually disappearing

At the age of 76 there was an episode with different features. A typical attack occurred but as the day progressed he experienced several more. On the next day an aura lasted 2 hours. The following day two more attacks occurred, each of ten minutes' duration. Throughout the subsequent day similar episodes recurred, about twelve in all. All auras were in the left visual field. Later that day he had a severe, steady pain behind the right eye and began to feel cold although the day was hot; his temperature was 37.6°C. He assumed that the pyrexia was due to sinusitis, as he had developed a yellow nasal discharge in the previous few days. With amoxicillin the temperature became normal within a day and the nasal discharge cleared. The last visual episode, still on the left, occurred on the subsequent day, lasting twenty minutes, but was joined by a right-sided headache starting ten minutes later; the aura and headache persisted together for another thirty minutes, when the aura disappeared, although the headache continued for a further hour. He then noticed a faint glow surrounding bright white objects—for example, around the edges of the kitchen dishwasher—which lasted over the next few hours. There were no further attacks in the subsequent nine months.

The previous history is relevant. A year earlier, mild effort intolerance had been treated with a coronary artery stent. At that time a raised blood cholesterol was found and was restored to normal with atorvastatin. He noticed an increased nasal discharge and a hoarse voice—a rare side effect. A month before the above episode, his general practitioner therefore changed the statin to simvastatin, which both increased and thickened the discharge which became yellow a week before this episode. Chronic lymphatic leukaemia had been diagnosed 8 years previously and remained well controlled; because of this he took an antibiotic whenever he developed a cold but did not do so on this occasion. In the past he had had many febrile upper respiratory infections, but had never experienced an aura during these. Previously he had not had multiple attacks, headache or post-aura light sensitivity. In childhood he had had no travel sickness or recurrent abdominal pain. His sister had migraine with aura; no other family member was known to have migraine currently or in the past.

COMMENT

Alvarez¹ described similar personal experiences. His aura began in youth, occurred about once a month for no apparent reason, and was not followed by a headache until age 67: the headache was then mild but he did not state its site or duration. Aged 72, he had two attacks on one day and two more three days later associated with ‘a trace of fever’ due to a saphenous vein thrombosis. On one occasion after an aura in the morning, he noticed that afternoon at a musical recital that he felt ‘distressed by a brilliant afterimage of the piano which I got if I looked at it for more than a few seconds.’ Perhaps the white piano keys were responsible. Alvarez also recorded one patient whose vision remained hypersensitive for five hours after an aura.

Migraine aura without headache is well recognized. The International Headache Society Classification² specifies the aura duration as usually less than sixty minutes, though sometimes longer. However, scant attention has been given to the mechanism(s) of increased number or changes in pattern of attacks as in this case. The additional headache here could have arisen from meningeal vasodilatation by extension of mucosal vasodilatation in the nasopharynx and paranasal sinuses secondary to the infection.³ Observations during migraine episodes indicate that the headache arises from nociceptive nerve endings of the meninges,⁴ the brain itself being insensitive to pain. More difficult to explain is the increased frequency of the visual aura and its increased duration. If the aura arises in the occipital cortex⁵ perhaps the pyrexia was contributory.