Page 60 - Migraine, the heart and the brain

Chapter 3
methods
Study population and procedures.
Study participants were invited from the CAMERA-2 study,3 which was primarily designed to assess the prevalence, incidence, and progression of MRI-detectable ischemic brain lesions in migraineurs over a 9-year follow-period from the CAMERA-1 study.2
In CAMERA-1, 295 well-characterized individuals with migraine20 and 140 controls who were randomly selected from a community-based study of the general population were included and assessed with brain MRI in 2000.2,21 For CAMERA-2, all original CAMERA-1 participants were invited in 2009 for a follow-up study, which included a structured computer-guided telephone interview, brain MRI, physical examination, and cognitive testing, all similar to the CAMERA-1 protocols.3 Although MRI scanners had signi cantly improved over the follow-up period, we decided to use the same MRI scanners in CAMERA-2 as in CAMERA-1 to preclude nding changes solely due to improved technology and sensitivity. Transcranial Doppler with air contrast (TCD-c) was performed on the same day as the MRI. MRI and TCD-c were performed and read without knowledge of migraine status.
Standard protocol approvals, registrations, and patient consents.
The study was approved by the ethics committees and participants gave written informed consent.
Outcome measures.
The primary outcome measure was the prevalence of RLS in migraineurs with and without aura compared to controls. Secondary outcome measures were the prevalence of ongoing recurrence of migraine attacks (de ned as having had at least one migraine attack in the previous 12 months)22 in migraineurs with RLS compared to migraineurs with migraine but no RLS, and ischemic brain lesions in participants with RLS compared to those without.
RLS. Presence of RLS was determined by TCD-c in accordance with international guidelines and recent recommendations.23 Briefly, the right cubital vein was cannulated with a 20-G indwelling catheter. A microbubble (MB) medium was prepared by mixing 9 mL saline, 1 mL air, and 0.5 mL of participants’ own blood at least 10 times vigorously between 2 syringes connected by a 3-way tap and injected with the participant in supine position while insonating the middle cerebral artery through the temporal bone window. We used a hand-held 2-MHz probe connected
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