Magnetic resonance microscopy of the barramundi (Lates calcarifer) brain.

Magnetic resonance imaging (MRI) is an established technique for morphological imaging of the central nervous system. Despite its prevalent use in a range of taxa, few studies exist on the brains of teleosts. In this study, we present a detailed analysis of a teleost brain using high-resolution MRI. Images were acquired from a Bruker 16.4 T vertical magnet with a three-dimensional flash T(2)*-weighted image sequence. High contrast was obtained using Magnevist® and the following imaging parameters: a flip angle of 30°, a repetition time of 50 ms, an echo time of 14 ms, and an image matrix of 1024 × 400 × 400. The resulting isotropic resolution of 30 μm allowed us to thoroughly describe the architecture of the barramundi (Lates calcarifer) brain, including descriptions of nuclei, fiber tracts, and cellular layers. A good correspondence, both in contrast and morphology, was found between magnetic resonance images and Nissl-stained brain sections, allowing for an analysis of the benefits and drawbacks of MRI and conventional histology.