Abstract
The feasibility of BOLD fMRI in association with electrical somatosensory stimulation on spontaneously breathing, isoflurane-anesthetized mice was investigated using spin-echo, echo-planar imaging (EPI) on a vertical narrow-bore 9.4 T magnet. Three experiments were performed to derive an optimal fMRI protocol. In Experiment 1 (n = 9), spin-echo BOLD responses to 10% CO 2 challenge under graded isoflurane (0.25-1.25%) ranged from 10 ± 2% to 3.5 ± 0.9%; the optimal BOLD contrast-to-noise ratio peaked at 0.75% isoflurane. In Experiment 2 (n = 6), hindpaw somatosensory stimulations using 1-7 mA under 0.75% isoflurane revealed the optimal BOLD response was at 6 mA. In Experiment 3 (n = 5), BOLD responses to 4 and 6 mA stimulation under 0.75% and 1% isoflurane were evaluated in detail, confirming the optimal conditions in Experiment 2. These results demonstrated that. BOLD fMRI using single-shot, spin-echo EPI in a mouse somatosensory stimulation model could be routinely performed on high-field, vertical, narrow-bore magnets. This protocol might prove useful for fMRI studies of transgenic mice.
Original language | English (US) |
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Pages (from-to) | 430-434 |
Number of pages | 5 |
Journal | Magnetic Resonance in Medicine |
Volume | 52 |
Issue number | 2 |
DOIs | |
State | Published - Aug 2004 |
Externally published | Yes |
Keywords
- High fields
- Hypercapnia
- Isoflurane anesthesia
- Microimager
- Somatosensory stimulation
- Spin-echo
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging