3T MR of the prostate: reducing susceptibility gradients by inflating the endorectal coil with a barium sulfate suspension.
Most prostate MRI/MRS examinations are performed with an endorectal coil inflated with air, leading to an air-tissue interface that induces magnetic susceptibility gradients within the gland. Inflation of the coil with a barium sulfate suspension is described and compared to inflation with air or liquid perfluorocarbon (PFC). The B(0) field in the prostate gland was mapped for five healthy volunteers when the endorectal coil was inflated with each of the three agents. A marked decrease in the posterior-anterior (P-A) field gradient and a significant improvement in field homogeneity were evident in the presence of a barium suspension and PFC relative to air. MRS data acquired from the prostate gland in the presence of air, PFC, and a barium suspension in the endorectal coil showed similar trends, demonstrating improvement in line-widths and spectral resolution when the barium suspension or the PFC were inflating the endorectal coil. On this basis we conclude that a barium suspension provides an available, cheap, and safe alternative to PFC, and we suggest that inflating the endorectal coil with a barium suspension should be considered for prostate MR studies, especially at high field strengths (such as 3T).
Rosen
Yael
Y
Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
Bloch
B Nicolas
BN
Lenkinski
Robert E
RE
Greenman
Robert L
RL
Marquis
Robert P
RP
Rofsky
Neil M
NM
D000328:Adult; D000388:Air; D001466:Barium Sulfate / Q000008:administration & dosage*; D003287:Contrast Media / Q000008:administration & dosage*; D005466:Fluorocarbons; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000033:anatomy & histology*; D018709:Statistics, Nonparametric
D003287:Contrast Media; D005466:Fluorocarbons; D001466:Barium Sulfate