Microembolic air load during contrast-transcranial Doppler: a trigger for migraine with aura?
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Published on: June 2, 2014
Luigi Caputi1, Susanna Usai, Maria R Carriero
1Department of Cerebrovascular Diseases, Neurological Institute C. Besta, Milan, Italy.
Background:
There is a well-known association between migraine with aura (MA) and right-to-left shunt (RILES) because of patent foramen ovale (PFO). The occurrence of MA attacks after microbubble (MB) injection during contrast-enhanced transcranial Doppler (ce-TCD) has been recently described.
Objectives:
The aim of this study was to analyze the prevalence of RILES in a consecutive cohort of MA patients and to characterize the occurrence of MA attacks after diagnostic ce-TCD.
Methods:
A total of 159 consecutive MA patients underwent ce-TCD with air-mixed saline to disclose RILES. RILES was characterized in terms of MB amount (small-moderate or large) and occurrence at rest and/or during Valsalva maneuver (permanent or latent).
Results:
RILES was revealed in 79/159 patients (∼ 50%). Permanent RILES were detected in 56/79 (71%) and latent RILES in 23/79 (29%) MA patients. The occurrence of a typical MA attack was overall observed in 12/159 patients (7.5%; 95% CI: 4-12.8%), but arose only in RILES-positive ones, immediately after ce-TCD (12/79; 15.2%; P< .001). All 12 patients had permanent RILES (12/56; 21.4%; P= .015) and MA attack was mostly observed in large RILES-positive patients, even without statistical significance (P= .118).
Conclusions:
Microembolic air load could act as a trigger of MA attack. According to recent studies and to the clinical characteristics observed in our patients, microembolization because of MB injection might provoke a decrease in cerebral oxygen saturation, thus triggering cortical spreading depression and, thereafter, MA attack. Larger and prospective studies will be necessary to confirm our data and observe a wider correlation.
Insights
Migraine with aura (MA) is linked to right-to-left shunts (RILES). Microbubble injection during transcranial Doppler can trigger MA attacks in patients with RILES.
Area of Science:
- Neurology
- Cardiology
- Diagnostic Imaging
Background:
- Migraine with aura (MA) is associated with right-to-left shunts (RILES) due to patent foramen ovale (PFO).
- Recent observations suggest MA attacks can occur after microbubble (MB) injection during contrast-enhanced transcranial Doppler (ce-TCD).
Purpose of the Study:
- To determine the prevalence of RILES in MA patients.
- To characterize MA attack occurrence following diagnostic ce-TCD.
Main Methods:
- 159 consecutive MA patients underwent ce-TCD with air-mixed saline.
- RILES were classified by MB amount (small-moderate/large) and presence at rest/Valsalva (permanent/latent).
Main Results:
- RILES detected in approximately 50% (79/159) of MA patients.
- MA attacks occurred in 7.5% of all patients, exclusively in RILES-positive individuals (15.2%).
- Attacks were more frequent in permanent RILES (21.4%) and large RILES, particularly after ce-TCD.
Conclusions:
- Microembolic air load from MB injection may trigger MA attacks.
- This microembolization could reduce cerebral oxygen saturation, initiating cortical spreading depression and subsequent MA.
- Larger, prospective studies are needed to confirm these findings and explore correlations.
