Functional connectivity fMRI in mouse brain at 7T using isoflurane.

Although many resting state fMRI human studies have been published, the number of such rodent studies is considerably less. The reason for this is the severe technical challenge of high magnetic field small rodent imaging. Local magnetic field susceptibility changes at air tissue boundaries cause image distortion and signal losses. The current study reports measures of functional connectivity in mice using only isoflurane for the anesthetic. Because all anesthetic agents will alter cerebral blood flow and cerebral metabolism, the impact these changes have on neuronal connectivity has yet to be fully understood, however this work reports for the first time that reliable functional connectivity measures in mouse brain can be obtained with isoflurane.