A delayed class of BOLD waveforms associated with spreading depression in the feline cerebral cortex can be detected and characterised using independent component analysis (ICA)

• Published in: Magnetic resonance imaging 2003-11, Vol.21 (9), p.1097-1110
• Main Authors: Netsiri, Chaiyapoj, Bradley, Daniel P., Takeda, Tsunehiro, Smith, Martin I., Papadakis, Nikolas, Hall, Laurance D., Parsons, Andrew A., James, Michael F., Huang, Christopher L.-H.
• Format: Article
• Language: English
• Subjects: Animal model; Animals; Anticonvulsants - pharmacology; Benzamides - pharmacology; Benzopyrans - pharmacology; Biological and medical sciences; Cats; Cerebral Cortex - drug effects; Cerebral Cortex - physiology; Cerebrovascular Circulation - drug effects; Cerebrovascular Circulation - physiology; Cortical Spreading Depression - drug effects; Cortical Spreading Depression - physiology; Female; Headache; ICA; independent component analysis; Magnetic Resonance Imaging - methods; Medical sciences; Migraine; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Serotonin 5-HT1 Receptor Agonists; Spreading depression; Sumatriptan - pharmacology; Technology. Biomaterials. Equipments. Material. Instrumentation
• ISSN: 0730-725X; 1873-5894
• DOI: 10.1016/S0730-725X(03)00199-1

An application of independent component analysis to blood oxygenation level- dependent MRI (BOLD-MRI) results was used to detect cerebrovascular changes that followed the initiation of cortical spreading depression (CSD) in feline brain. The cortical images were obtained from a horizontal plane at 28 s intervals before, and for 1.4–1.75 h after, KCl dissolved in agar (KCl/agar) had been directly applied to the left suprasylvian gyrus of 13 anesthetized cats for 10 min. It successfully resolved, for the first time, a novel class of prolonged, and delayed, biphasic BOLD waveforms. These were larger in amplitude (∼20%), longer lasting and more delayed in onset (13–33 min) than the brief propagating (90 s) BOLD increase (∼4%) already known to be associated with CSD on earlier occasions. Furthermore, such changes occurred in localized regions on the hemisphere ipsilateral to the site of stimulus application in 4 out of 5 control subjects rather than themselves generating propagating waves. Finally, the biphasic waveforms were consistently abolished in the 4 experimental animals studied following the i.v. administration of sumatriptan (0.3 mg kg −1), an antimigraine 5-HT 1B/1D agonist, 15 min before the application of the transient stimulus. They were abolished in 2 out of 4 animals following the intraperitoneal (i.p.) administration of SB-220453 (tonabersat: 10 mg kg −1, 90 min before stimulus application), a novel anticonvulsant that has recently been reported to inhibit CSD. ICA has thus been successful in detecting a novel localized, as opposed to propagating, signal of potential physiological significance hidden in complex BOLD- MRI data, whose sensitivity to sumatriptan may relate it to the cerebrovascular changes reported in the headache phase of migraine.