A two-dimensional (2D) chemical shift correlated MR spectroscopic (COSY) sequence integrated into a new volume localization technique (90°-180°-90°) is proposed for whole-body MR spectroscopy (MRS).Due to the recent improvements in the design of B 0 gradient and RF coils, 1 H MR spectra have been recorded in human brain with excellent water suppression using short TE, as short as 15 ms, and several cerebral metabolites have been identified (1-4). During the past decade alterations in several metabolites, namely, N-acetylaspartate (NAA), glutamate/glutamine (Glx), choline (Ch), creatine (Cr), myo-inositol (mI), and ␥-aminobutyrate (GABA) have been reported in different pathologic states involving the central nervous system (CNS) (5-10). Absolute quantitation of cerebral metabolites in vivo has also been reported for only a few metabolites, albeit with limited success (11-13). Due to severe overlap of these metabolites, an unambiguous assignment of J-coupled metabolite multiplets is severely hindered at 1.5 T field strength.One-dimensional (1D) MR spectral editing techniques to unravel the overlapping resonances rely on J-coupled proton metabolites that have well-separated multiplets. A technique based on subtraction methodology is very sensitive to motion artifacts leading to subtraction errors. An additional drawback is that only one metabolite can be identified at a time. Successful attempts in editing GABA and glutamate using whole-body MRI/MRS scanners have been presented by other researchers (13,14). Single-shotbased multiple-quantum filtered MR spectroscopic sequences have also been implemented on whole-body scanners, but a severe signal loss associated with various coherence transfer pathways made it less attractive to human applications (15)(16)(17).A localized version of a two-dimensional (2D) J-resolved MR spectroscopic (JPRESS) sequence using the PRESS sequence for volume localization was recently proposed (18 -20). Even though the JPRESS sequence retains 100% of the magnetization from a localized volume of interest (VOI), the strong coupling effect inherent at 1.5 T field strength resulted in a complex 2D cross-peak pattern for NAA, glutamate/glutamine, GABA, and other cerebral metabolites (19). Also, some of the 2D cross-peaks were heavily T 2 -weighted during the long incremental delays necessitated by the second dimension of the JPRESS spectrum. An oversampled J-resolved sequence has also been proposed recently (21).Compared to the 2D J-resolved spectra, a COSY spectrum produces a better dispersion of J-cross-peaks, although it requires a larger spectral window to be sampled during the evolution period (22). Different versions of the localized COSY sequence have been implemented by other researchers (23-33). McKinnon and Bosiger (23) proposed a conventional COSY sequence with hard RF pulses (90°-t 1 -90°) followed by three volume selective 180°RF pulses. Haase et al. (24) implemented a COSY combined with an outer volume suppressing sequence, namely, LOCUS. Many previous attempts to develop localiz...

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OBJECTIVE.: To analyze the risk factors for new-onset diabetes mellitus (NODM) in liver transplant recipients using the Organ Procurement and Transplant Network/United Network for Organ Sharing database. METHODS.: Among 20,172 primary liver recipients (age > or =18 years) transplanted between July 2004 and December 2008 in Organ Procurement and Transplant Network/United Network for Organ Sharing databases, 15,463 recipients without pretransplant diabetes were identified. Risk factors for NODM were examined using multivariate Cox regression analysis. RESULTS.: NODM was reported in 26.4% of recipients (median follow-up, 685 days). Independent predictors of NODM development included recipient age (> or = 50 vs. <50 years, hazard ratio [HR]=1.241), African American race (HR=1.147), body mass index (> or = 25 vs. <25, HR=1.186), hepatitis C (HR=1.155), recipient cirrhosis history (HR=1.107), donor age (> or = 60 vs. <60 year, HR=1.152), diabetic donor (HR=1.151), tacrolimus (tacrolimus vs. cyclosporine, HR=1.236), and steroid at discharge (HR=1.594). Living donor transplant (HR=0.628) and induction therapy (HR=0.816) were associated with a decreased risk of NODM. CONCLUSION.: The incidence of NODM was 26.4% in liver recipients with a median follow-up time of 685 days. Identified risk factors for NODM in liver transplantation were similar to that in kidney transplantation. Some of the identified factors are potentially modifiable, including obesity and the choice of immunosuppressive regimens.

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