Rectal carcinoma: MRI with histologic correlation before and after chemoradiation therapy.

Objective: The purpose of this study was to use MRI to compare the morphologic features of rectal cancer before and 6 weeks after chemotherapy and radiation treatment to correlate the posttreatment MRI appearances with the histologic findings in resected tumors.

Materials And Methods: High-resolution T2-weighted MRI was performed before and immediately after a standardized 5-week course of chemoradiation therapy in the care of 30 patients with locally advanced adenocarcinoma of the rectum. Changes in morphologic features were evaluated with respect to primary tumor and nodal downstaging.

Localized COSY and DQF-COSY 1H-MRS sequences for investigating human tibial bone marrow in vivo and initial application to patients with acute leukemia.

Purpose: To develop 2D 1H-MRS measurement sequences for the evaluation of bone marrow lipids, and to assess these measurement sequences in healthy and diseased bone marrow.

Materials And Methods: Single-voxel localized variants of COSY and DQF-COSY 2D 1H-MRS sequences were developed for use at 1.5 T to investigate the biochemical composition of human bone marrow in vivo.

Identification of biliary metabolites of ifosfamide using 31P magnetic resonance spectroscopy and mass spectrometry.

Biliary excretion is a significant component in the metabolism of many drugs, but remains difficult to detect and characterise non-invasively. A previous publication recently described the detection of metabolites of ifosfamide in gall bladder in a guinea pig model using in vivo 1H-decoupled 31P 3-D magnetic resonance spectroscopic imaging and a clinical 1.5 T MR scanner.

Quantitative assessment of the hepatic pharmacokinetics of the antimicrobial sitafloxacin in humans using in vivoF magnetic resonance spectroscopy.

Aims: To measure hepatic concentrations of the fluorine-containing antimicrobial, sitafloxacin, using in vivo(19)F magnetic resonance spectroscopy (MRS).

Methods: Data were acquired from eight healthy subjects at 2, 5, 8 and 24 h following doses of 500 mg day(-1) for 5 days using a (1)H/(19)F surface coil in a 1.5T clinical MR system.

Human gallbladder bile: noninvasive investigation in vivo with single-voxel 1H MR spectroscopy.

Proton (hydrogen 1) magnetic resonance (MR) spectroscopy was used to study model and porcine bile in vitro. The method was subsequently developed to facilitate the acquisition of in vivo 1H MR spectra from the gallbladder bile of 10 human volunteers. Signals attributable to phosphotidylcholine and conjugated bile acid protons were observed in eight of the 10 volunteers.

Ifosfamide pharmacokinetics and hepatobiliary uptake in vivo investigated using single- and double-resonance 31P MRS.

MRS has considerable potential for the measurement of drug pharmacokinetics in vivo. In this study single- and double-resonance (31)P MRS was used to investigate the biodistribution, pharmacokinetics, and metabolism of ifosfamide following administration of 500 mg/kg ifosfamide in guinea pigs. (1)H-decoupling was found to nearly double the signal of detected peaks.

The effect of Gd-DTPA on T(1)-weighted choline signal in human brain tumours.

The influence of Gd-DTPA on T(1)-weighted (T(1)W) proton MR spectra has been investigated in 19 patients with histologically verified low (n = 13) or high-grade (n = 6) gliomas. Repeat measurements were performed on 9 patients (7 low-grade and 2 high-grade), with 28 examinations performed in total. Comparison of spectra obtained before and after 0.