Noninvasive High Field MRI Brain Imaging of the Garter Snake (Thamnophis sirtalis)
This report documents the application of high field magnetic resonance imaging to viewing the central nervous system of garter snakes (12–43 g) with emphasis on the vomeronasal and olfactory systems. Slices in all three planes were taken in lightly sedated snakes showing many major neural structures with resolution down to less than 60 µm. The images were obtained as 8 or 16 serial slices with slice spacings of 0.25 mm and 0.25 mm thick and were processed to a 256 × 256 matrix with a field of view (FOV) of 14 or 25 mm. The vomeronasal organs, main and accessory olfactory bulbs, telencephalon, cortex, tectum, medulla, cerebellum, spinal cord, and other major features of the brain are clearly defined in the images. The value of noninvasive neural imaging in comparative and experimental studies of squamate reptiles will become increasingly recognized as the technology is further developed but can be effectively employed at present.Abstract
A graphical representation of the SEMS pulse sequence used in these studies
A multislice dorsal image of garter snake 6077. Structure labels in Table 1
Two sagittal views of garter snake 6076. Structure labels in Table 1
A higher resolution sagittal view of the olfactory bulb and the vomeronasal organ in garter snake 1686H. Structure labels in Table 1