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In recent years, proton magnetic resonance spectroscopy (MRS) has emerged as a non-invasive technique for measurement of fat content in the liver. The technique is often applied for overweight and obese patients. However, excessively obese patients cannot be examined in most conventional magnetic resonance systems due to limited space. The purpose of this study was to examine the ability of open 1T system to monitor liver fat with proton MRS and to compare hepatic fat fractions (HFFs) obtained using an open 1T system with assessment with 3T proton MRS.The study included 23 children and adolescents up to 20 years of age with a body mass index above the 97th percentile according to age and gender. Proton MRS for each patient was performed in both 1T and 3T using point resolved spectroscopy sequence in a single volume positioned in the right liver lobe.Average T2 relaxation times obtained for an open 1T system (55 ± 7 ms for water and 85 ± 11 ms for fat) were higher than average T2 relaxation times obtained for a 3T system (31 ± 4 ms for water and 66 ± 10 ms for fat). HFFs measured using an open 1T system showed strong correlation with HFFs measured using a 3T system (r = 0.99, P0.0001).Proton MRS measurements of HFF with an open 1T system are feasible. Open 1T system may reliably replace 3T magnetic resonance system for the assessment of liver fat.

MR colonography (MRC) is a non-invasive method of examining the colon, but it is still only used in a few specialized centers on a daily basis. The purpose of this study was to evaluate the performance of MRC with improved fecal tagging vs. conventional colonoscopy (CC). Between March 2006 and February 2007, consecutive patients who received first-time referrals to CC were asked to participate in the study. Two days prior to MRC, a new contrast mixture (barium/ferumoxsil) was ingested together with four meals each day. Standard bowel cleansing was performed before CC. MRC was evaluated by two blinded observers. MRC results were compared with CC. A total of 56 patients were included. The per-polyp sensitivity was 85.7% for polyps 6–10 mm and 81.3% for polyps >10 mm. The per-patient sensitivity/specificity was 100%/80% for polyps >6 mm and 100%/91.4% for polyps >10 mm. MRC showed acceptable per-patient sensitivities, but the per-polyp sensitivities are still compromised by the fecal tagging. MRC may be implemented, but at the present time MRC with fecal tagging is not ready for widespread use, although it remains a very promising diagnostic tool.

MR colonography (MRC) is a promising method of examining the colon, but is limited to a few specialist centres. The purpose of this article was to describe the implementation of MRC with fecal tagging. Patients referred for conventional colonoscopy (CC) were offered MRC with fecal tagging before CC. Two days before MRC patients ingested an oral contrast agent. Before and after MRC and CC a number of questions were addressed. MR images were rated by a blinded investigator. In 6 months, 30 consecutive patients were included. The median time in the MR suite was 44 min, 23 min for the MRC examination and 9 min for the evaluation. The median time for CC was 32 min. Sixty-six percent of the patients preferred MRC as the future method of examination, 10% preferred CC, 21% had no preferences. Of the oral contrast agents, barium sulphate with ferumoxsil was significantly better than barium sulphate alone. The majority of the patients found MRC less unpleasant than CC and a majority would prefer MRC over CC as a future colon examination. MRC also appears to be less time consuming to the patients and medical personnel than CC with post-procedural monitoring.