Spatially localized two-dimensional spectroscopy. SLO-COSY and SLO-NOESY

Blackband, Stephen J.; McGovern, Kathy Ann; McLennan, Ian J.

doi:10.1016/0022-2364(88)90337-x

Cited by 10 publications

(16 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Earlier studies used the localized and nonlocalized versions of 2D MRS techniques on animal MRI scanners, showing applications using phantom solutions, rat brain and rabbit kidney. [8][9][10][11][12] Dreher et al recorded 4.7 T brain spectra and also demonstrated the possibility of recording homonuclear decoupled spectra in rat brain in vivo using 2D J-resolved spectroscopy. 13 Doddrell and coworkers implemented a localized version of a 2D correlated spectroscopic sequence, namely VOSY-COSY, on a 2 T MRI/MRS scanner to record brain COSY spectra.…”

Section: Introductionmentioning

confidence: 96%

Evaluation of two‐dimensional L‐COSY and JPRESS using a 3 T MRI scanner: from phantoms to human brain in vivo

et al. 2003

View full text Add to dashboard Cite

Localized versions of two-dimensional (2D) magnetic resonance spectroscopic (MRS) sequences, namely JPRESS and L-COSY, have been implemented on a whole-body 3T MRI/MRS scanner. Volume selection was achieved using three slice-selective radio-frequency (RF) pulses: 90 degrees-180 degrees-180 degrees in JPRESS and 90 degrees-180 degrees-90 degrees in L-COSY with a CHESS sequence prior to voxel localization for global water suppression. The last 180 degrees RF pulse was used for resolving the J-coupled cross peaks in JPRESS, whereas the last 90 degrees RF pulse was used for coherence transfer between J-coupled metabolites in L-COSY. A head MRI coil for 'transmission' and a 4 inch receive surface coil for 'reception' or a head coil transmit/receive were used. A total of 16 healthy volunteers were investigated using these 2D MRS sequences. Voxel sizes of 18 and 27 ml were localized in the occipito-parietal gray and white matter regions and the total duration for each 2D signal acquisition was typically 35 min. Compared with 2D L-COSY, reduced spectral width along the second spectral dimension and shorter 2D spectral acquisition were the major advantages of 2D JPRESS. In contrast, increased spectral width along the new spectral dimension in L-COSY resulted in an improved spectral dispersion enabling the detection of several brain metabolites at low concentrations that have not been resolved using the conventional one-dimensional (1D) MRS techniques. Due to increased sampling rate, severe loss of metabolite signals due to T2 during t1 was a major drawback of 2D JPRESS in vivo.

show abstract

Section: Introductionmentioning

confidence: 96%

Evaluation of two‐dimensional L‐COSY and JPRESS using a 3 T MRI scanner: from phantoms to human brain in vivo

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Single shot localization methods are potentially not limited in the same way as only one acquisition is required per t 1 increment. However all previously reported single shot 2D methods 5,6,8,9,11 have required both phase cycling of the the excitation pulses to remove unwanted coherences and signal averaging to improve signal to noise ratio, again limiting the number of t 1 increments that can be realized.…”

Section: Technical Considerationsmentioning

confidence: 98%

“…A number of techniques have previously been proposed for localized 2D acquisitions, 5,6,8,9,11,44 but only a few have demonstrated useful data in vivo. 6,8,11 Single shot localization methods have generally been employed.…”

Section: Technical Considerationsmentioning

confidence: 98%

“…[5][6][7][8][9][10][11] A common feature in all of these previously described sequences is the use of echo formation (either spin-or stimulated-echoes) for signal localization. With the exception of the CT-PRESS technique of Dreher et al 10 these approaches all suffer from modulation of the signal from J-coupled protons as a function of the echo time, leading to intensity and lineshape distortion and baseline roll.…”

Section: Introductionmentioning

confidence: 97%

“…With the exception of the CT-PRESS technique of Dreher et al 10 these approaches all suffer from modulation of the signal from J-coupled protons as a function of the echo time, leading to intensity and lineshape distortion and baseline roll. In those sequences based on stimulated echo localization [5][6][7][8] there is also an additional intrinsic loss of half of the available signal.…”

Section: Introductionmentioning

confidence: 98%

See 2 more Smart Citations

In vivo monitoring of rat brain metabolites during vigabatrin treatment using localized 2D‐COSY

et al. 2003

View full text Add to dashboard Cite

A two-dimensional COSY-based localization sequence was designed to allow the in vivo monitoring of proton metabolites in rat brain [particularly gamma-aminobutyric acid (GABA), glutamine, taurine and myo-inositol]. The sequence incorporated OSIRIS signal localization, B1-insensitive water suppression and phase-sensitive COSY acquisition. The method was used to study the effects of the GABA-transaminase inhibitor vigabatrin on rat brain metabolite concentrations. Wistar rats were treated daily for 3 days with an oral dose of vigabatrin (200 mg/kg, n = 4). Localized COSY spectra were obtained during a 120 min acquisition from a 270 microl central brain voxel and compared with nine untreated control animals. Significant elevations were observed in GABA (267% of control, p < 0.005, Mann-Witney test), glutamine (130% of control, p < 0.005) and taurine (113% of control, p < 0.05). Changes in GABA and taurine were consistent with previous data on the action of Vigabatrin, and support a previously hypothesized link between these compounds. The increase in glutamine was more surprising and may reflect the balance between the level and/or site of GABA-transaminase inhibition and downregulation of GABA synthesis.

show abstract

Fast echo planar based correlation-peak imaging: Demonstration on the rat brain in vivo

2000

View full text Add to dashboard Cite

Spatially localized two-dimensional spectroscopy. SLO-COSY and SLO-NOESY

Cited by 10 publications

References 14 publications

Evaluation of two‐dimensional L‐COSY and JPRESS using a 3 T MRI scanner: from phantoms to human brain in vivo

Evaluation of two‐dimensional L‐COSY and JPRESS using a 3 T MRI scanner: from phantoms to human brain in vivo

In vivo monitoring of rat brain metabolites during vigabatrin treatment using localized 2D‐COSY

Fast echo planar based correlation-peak imaging: Demonstration on the rat brain in vivo

Contact Info

Product

Resources

About