Journal of neuroscience methods
-
J. Neurosci. Methods · Apr 2011
Intra- and extra-cranial effects of transient blood pressure changes on brain near-infrared spectroscopy (NIRS) measurements.
Brain near-infrared spectroscopy (NIRS) is an emerging neurophysiological tool that combines straightforward activity localization with cost-economy, portability and patient compatibility. NIRS is proving its empirical utility across specific cognitive and emotional paradigms. However, a potential limitation is that it is not only sensitive to haemodynamic changes taking place in the cortex, and task-related cardiovascular responses expressed in the perfusion of extracranial layers may be confounding. ⋯ However when blood pressure was actively manipulated, this effect was absent and replaced by a very large pressure-related response. Our observations demonstrate that blood pressure fluctuations can exert confounding effects on brain NIRS, through expression in extracranial tissues and within the brain itself. We highlight the necessity for continuous blood pressure monitoring alongside brain NIRS, and for further research on methods to correct for physiological confounds.
-
J. Neurosci. Methods · Apr 2011
Ipsilateral, cabled sural nerve for a sciatic nerve defect: an experimental model in the rat.
The 10 mm rat sciatic nerve defect model is commonly used to investigate new strategies to improve functional recovery with segmental nerve defects. However, a lack of standardization makes comparisons between studies difficult. The present study aims to evaluate a standardized experimental model that can minimize the number of animals required for obtaining valid results and simulates a current treatment for human peripheral nerve injury defects. ⋯ The results support functional recovery of the sciatic nerve in all grafted animals. The use of an ipsilateral cabled sural nerve graft technique in the rat sciatic nerve defect model is a viable control group that utilizes a single incision, incurs minimal morbidity, and maintains muscle attachments. We conclude that this rat model can be used in various experimental trials in the field of peripheral nerve regeneration.