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To compare in vivo 1H magnetic resonance (MR) spectra of preinvasive and invasive cervical lesions with ex vivo magic angle spinning (MAS) spectra of intact biopsies from the same subjects and to establish the effects of tumor load in the tissue sampled on the findings. A total of 51 subjects (nine with normal cervix, 10 with cervical intraepithelial neoplasia [CIN], and 32 with cervical cancer) underwent endovaginal MR at 1.5 T. Single-voxel (3.4 cm3) 1H MR spectra were acquired and voxel tumor load was calculated (tumor volume within voxel as a percentage of voxel volume). Resonances from triglycerides –CH2 and –CH3 and choline-containing compounds (Cho) were correlated with voxel tumor load. Biopsies analyzed by 1H MAS-MR spectroscopy (MRS) had metabolite levels correlated with tumor load in the sample at histology. In vivo studies detected Cho in normal, CIN, and cancer patients with no significant differences in levels (P = 0.93); levels were independent of voxel tumor load. Triglyceride –CH2 and –CH3 signals in-phase with Cho were present in 77% and 29%, respectively, of cancer subjects (but not in normal women or those with CIN), but did not correlate with voxel tumor load. Ex vivo cancer biopsies showed levels of triglycerides –CH2 and –CH3 and of Cho that were significantly greater than in normal or CIN biopsies (P < 0.05); levels were independent of the tumor load in the sample. The presence of –CH2 in vivo predicted the presence of cancer with a sensitivity and specificity of 77.4% and 93.8% respectively, positive (PPV) and negative (NPV) predictive values were 96% and 68.2%; for –CH2 ex vivo, sensitivity was 100%; specificity, 69%; PPV, 82%; and NPV, 100%. Elevated lipid levels are detected by MRS in vivo and ex vivo in cervical cancer and are independent of tumor load in the volume of tissue sampled. J. Magn. Reson. Imaging 2004;19:356–364. © 2004 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The objective of this study was to establish in vivo 1H-magnetic resonance (MR) spectroscopic appearances of cervical cancer using an endovaginal receiver coil and corroborate findings with magic angle spinning (MAS) MR spectroscopy of tissue samples. Fifty-three women (14 controls and 39 with cervical cancer) underwent endovaginal coil MR imaging at 1.5 T with T1- and T2-weighted scans sagittal and transverse to the cervix. Localized 1H MR spectra (PRESS technique, TR 1600 ms, TE 135 ms) were accumulated in all controls and 29 cancer patients whose tumour filled > 50% of a single 3.4 cm3 voxel. Peaks from triglyceride-CH2 and -CH3 were defined as present and in-phase (with the choline resonance), present but out-of-phase, or not present. Peak areas of choline-containing compounds were standardized to the area of unsuppressed tissue water resonance. Comparisons in observed resonances between groups were made using Fisher''s exact test (qualitative data) and a t-test (quantitative data). Biopsies from these women analysed using MAS-MR spectroscopy and normalized to the intensity of an external standard of silicone rubber were similarly compared. Adequate water suppression permitted spectral analysis in 11 controls and 27 cancer patients. In-phase triglyceride-CH2 resonances (1.3 ppm) were observed in 74% of tumours but in no control women (p < 0.001). No differences were observed in the presence of a 2 ppm resonance, choline-containing compounds or creatine in cancer compared with control women. However, ex vivo analysis showed significant differences not only in —CH2, but also in —CH3, a 2 ppm resonance, choline-containing compounds and creatine between tissues from control women and cancer tissue (p < 0.001, = 0.001, = 0.036, < 0.001 and = 0.004 respectively). On in vivo 1H-MR spectroscopy, the presence of positive triglyceride-CH2 resonances can be used to detect and confirm the presence of cervical cancer. However, technical improvements are required before routine clinical use. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To construct an inductively-coupled receiver coil system for use with a magnetic resonance (MR) compatible endoscope, and to evaluate its use in a pilot group of patients with esophageal cancer. An inductively-coupled coil system, comprising a saddle geometry cylindrical receiver coil fitted as a sleeve around the endoscope tip and a pick-up coil housed within a channel of an MR-compatible endoscope, was designed and developed for use at 0.5 T. Twenty-three patients with esophageal cancer were recruited for MR endoscopy. In 17 cases, the endoscopic coil system was used in conjunction with an external surface coil in order to obtain information from the surrounding mediastinum. The examination took 40–50 minutes. MR imaging using the inductively-coupled endoscopic coil was successful in 21 cases (one failed intubation and one artifact from unrelated external source). Image artifact was largely due to respiration and global patient motion in sedated individuals undergoing endoscopy. Inductively-coupled coil systems may be used with endoscopes to allow improved safety through increased patient-system isolation and detachability of coils and electronics for repair or replacement with coils tuned for different frequencies. J. Magn. Reson. Imaging 2003;18:131–135. © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]