TY - CHAP M1 - Book, Section TI - MAGNETIC RESONANCE IMAGING IN OBSTETRICS A1 - Twickler, Diane M. A2 - Fleischer, Arthur C. A2 - Toy, Eugene C. A2 - Lee, Wesley A2 - Manning, Frank A. A2 - Romero, Roberto J. PY - 2015 T2 - Sonography in Obstetrics and Gynecology: Principles & Practice, 7e AB - DefinitionsDiffusion-weighted imaging: an MR sequence that produces images of water diffusion, which reflects hypoxic edema of the brain.MR imaging: modality that uses high field strength magnets, radio frequencies, and a computerized analysis to produce detailed in vivo images of internal anatomy of the body.Orthogonal views: MR views at right angles to each other, typically axial, coronal, and sagittal views of the fetus.Signal void: the appearance of darkness on an image based on low MR signal that helps characterize tissues and fluid on certain sequences.T2-weighted imaging: MR technique that defines fetal anatomy and dysmorphology with specific tissue characteristics based on a specific spin echo sequence using a long repetition time and long echo time.T1-weighted imaging: MR technique that is less sensitive for anatomy but highlights certain characteristics of fat, certain stages of bleeding, liver, and meconium in the colon at later gestations based on a specific spin echo sequence using a short repetition time and short echo time.Volumetry: measurement by volume calculated by areas multiplied by slice thickness. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - obgyn.mhmedical.com/content.aspx?aid=1106711716 ER -