Magnetic Resonance Imaging of Black Widow Spider.

Gradient echo (GRE)-MRI images of a black widow spider (Fig. 1A) were collected using an 18.8T magnet (800 MHz) with a Varian VNMRS console and Doty Scientific 12 mm ID triple axis MRI gradient probe capable of producing up to 300 Gs/cm PFG along each axis. GRE-MRI images with 40 µm × 40 µm in plane resolution and 300-µm slice thickness were collected using a 4-ms echo time and 50-ms repetition time. Localized spectra utilized the STEAM2, a stimulated echo acquisition mode localization scheme, with an echo time of 2.3 ms, a mixing time of 4.5 ms, and a repetition time of 2 s. Additionally, outer voxel suppression pulses and variable power radiofrequency pulses with optimized relaxation delays (VAPOR) water suppression was employed (47). A 1.6-μL volume of interest was selected in the interior of the MA gland using pilot gradient echo images.