Metabolic imaging of patients with intracranial tumors: H-1 MR spectroscopic imaging and PET.

Luyten, Peter R.; Mariën, Ad J. H.; Heindel, Walter; Gerwen, P H van; Herholz, K.; Hollander, Jan A. den; Friedmann, Georges; Heiss, Wolf Dieter

doi:10.1148/radiology.176.3.2389038

Cited by 237 publications

(81 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In previous studies it was hypothesized that malignant tumours have a high metabolic rate (41). Additionally, some reports showed correlation between glucose consumption rate and lactate levels for gliomas, suggesting alterations in glycolysis in brain tumours (42). However, we did not find a statistically significant correlation between lactate levels and tumour grade.…”

Section: Resultscontrasting

confidence: 81%

Comparative metabolic profiling of paediatric ependymoma, medulloblastoma and pilocytic astrocytoma

Cuellar-Baena

Morales²,

Martinetto³

et al. 2010

Int J Mol Med

View full text Add to dashboard Cite

Abstract. Brain tumours are the most common solid tumours in children and a major cause of childhood mortality. The most common paediatric brain tumours include ependymomas, cerebellar astrocytomas and medulloblastomas. These brain tumours are highly heterogeneous regarding their histology, prognosis and therapeutic response. Subtle biochemical changes can be detected in intact tissues by High-Resolution Proton Magnetic Angle Spinning Spectroscopy (HR-MAS) revealing the status of tumour microheterogeneity and metabolic alterations before they are morphologically detectable. In this study, we present metabolic profiles by HR-MAS of 20 intact tissue samples from paediatric brain tumours. Tumour types include ependymoma, medulloblastoma and pilocytic astrocytoma. The metabolic characterization of paediatric brain tumour tissue by HR-MAS spectroscopy provided differential patterns for these tumours. The metabolic composition of the tumour tissue was highly consistent with previous in vivo and ex vivo studies. Some resonances detected in this work and not previously observed by in vivo spectroscopy also show potential in determining tumour type and grade (fatty acids, phenylalanine, glutamate). Overall, this work suggests that the additional information obtained by NMR metabolic profiling applied to tissue from paediatric brain tumours may be useful for assessing tumour grade and determining optimum treatment strategies.

show abstract

Section: Resultscontrasting

confidence: 81%

Comparative metabolic profiling of paediatric ependymoma, medulloblastoma and pilocytic astrocytoma

Cuellar-Baena

Morales²,

Martinetto³

et al. 2010

Int J Mol Med

View full text Add to dashboard Cite

show abstract

“…The use of the Cho/Cr ratio in the evaluation of neoplastic lesions has already been described in the literature as Cho is an important constitute of cell membranes with increases occurring when there are increases in cell synthesis and conversion to carcinogenic cells, while creatine is generally stable 8,9 . NAA is found in normal neurons and when altered, reductions occur both in tumors and in inflammatory lesions thereby indicating neuronal loss.…”

Section: Discussionmentioning

confidence: 99%

Application of magnetic resonance spectroscopy in the differentiation of high-grade brain neoplasm and inflammatory brain lesions

Ferraz-Filho

Santana-Netto

Rocha-Filho

et al. 2009

Arq. Neuro-Psiquiatr.

View full text Add to dashboard Cite

-This study aims at evaluating the application of magnetic resonance spectroscopy (MRS) in the differential diagnosis of brain tumors and inflammatory brain lesions. The examinations of 81 individuals, who performed brain MRS and were retrospectively analyzed. The patients with ages between 10 and 80 years old, were divided into two groups. Group A consisted of 42 individuals with diagnoses of cerebral toxoplasmosis and Group B was formed of 39 individuals with diagnosis of glial neoplasms. On analyzing the ROC curve, the discriminatory boundary for the Cho/Cr ratio between inflammatory lesions and tumors was 1.97 and for the NAA/Cr ratio it was 1.12. RMS is an important method useful in the distinction of inflammatory brain lesions and high-degree tumors when the Cho/Cr ratio is greater than 1.97 and the NAA/Cr ratio is less than 1.12. And so this method is important in the planning of treatment and monitoring of the therapeutic efficiency.Key WORdS: magnetic resonance image, spectroscopy, brain, neoplasm, inflammatory lesion. Aplicação da espectroscopia por ressonância magnética na diferenciação de lesões expansivas encefálicas neoplásicas e inflamatóriasresumo -O presente estudo tem como objetivo avaliar a aplicação da espectroscopia por ressonância magnética (eRM) no diagnóstico diferencial entre lesões expansivas encefálicas inflamatórias e neoplásicas. Foram analisados retrospectivamente 81 indivíduos que realizaram exames de eRM com idade entre 10 a 18 anos, divididos em dois grupos. O grupo A foi formado por 42 indivíduos com diagnóstico de neurotoxoplasmose e o grupo B foi formado por 39 indivíduos com diagnóstico de neoplasias gliais. Após análise da curva ROC observou-se que o valor discriminatório da relação Co/Cr entre lesões inflamatórias e neoplásicas foi de 1,97 e da relação Naa/Cr foi de 1,12. A espectroscopia por RM é um método útil na distinção de lesões expansivas inflamatórias e neoplasias de alto grau quando a relação Co/Cr é maior que 1,97 e a relação Naa/Cr é menor que 1,12, o que torna este método importante no planejamento do tratamento e monitorização da eficácia terapêutica.PAlAvRAS-ChAve: ressonância magnética, espectroscopia, encéfalo, neoplasia, lesão inflamatória. Magnetic resonance spectroscopy (MRS) is a relatively fast, non-invasive method that provides metabolic/ biochemical information of the normal brain parenchyma and of pathological processes 1,2 . Spectroscopy utilizes the same physical principles as conventional magnetic resonance, but differs in the way that the data are processed and presented;instead of images, amplitude by frequency plots are obtained 1 .There are few published studies concerning the differentiation between inflammatory lesions and brain tumors employing MRS and all that exist are related to the differential diagnosis of lymphoma and inflammatory lesions in

show abstract

“…Using arguments similar to those of Eqs. [2] and [4], they found that the SNRs of the two methods were indistinguishable when the TRs were the same, or when the TR was Ͻ T 1 and an Ernst angle was used. While both conditions can be met in MRI, where T C Ͻ Ͻ T 1 , neither is practical in MRS in general, especially for 3D 1 H-MRS.…”

Section: Fig 4 Topmentioning

confidence: 99%

“…This technique (see Fig. 1a), which is known as MRS imaging (MRSI) and was first described for 1 H by Luyten et al (4), yields much more spatial information at equal SNR (5), as determined by the voxel size and acquisition time (6). To reduce SNR loss from incomplete longitudinal relaxation, T 1 , the TR is extended beyond the actual acquisition-cycle, T C , the time needed to prepare and acquire one transient, as determined primarily by the desired spectral resolution.…”

mentioning

confidence: 99%

Optimizing the efficiency of high‐field multivoxel spectroscopic imaging by multiplexing in space and time

Goelman

Liu

Hess

et al. 2006

Magnetic Resonance in Med

View full text Add to dashboard Cite

A new strategy to yield information from the maximum number of voxels, each at the optimum signal-to-noise ratio (SNR) per unit time, in MR spectroscopic imaging (MRSI) is introduced. In the past, maximum acquisition duty-cycle was obtained by multiplexing in time several single slices each repetition time (TR), while optimal SNR was achieved by encoding the entire volume of interest (VOI) each TR. We show that optimal SNR and acquisition efficiency can both be achieved simultaneously by multiplexing in space and time several slabs of several slices, each. Since coverage of common VOIs in 3D proton MRSI in the human brain typically requires eight or more slices, at 3 T or higher magnetic fields, two or more slabs can fit into the optimum TR (ϳ1.6 s). Since metabolite concentrations in the brain are lower than tissue water by orders of magnitude, magnetic resonance spectroscopy (MRS) has been beset by inferior signal-to-noise ratio (SNR) per unit time compared to MRI. To partially compensate for this, MRS voxels are typically more than ϫ10 3 larger (cm 3 vs. mm 3 ), and acquisition times are ϫ10 2 -10 3 longer (many minutes vs. a few seconds) than MRI (1). It is not surprising, therefore, that substantial technical and methodological efforts have been made to improve the SNR and reduce the acquisition time of MRS, especially its most prevalent proton ( 1 H) variants. These efforts have progressed along two main paths. The first method involved multiplexing in space, i.e., increasing the spatial coverage from a single-to a simultaneous multivoxel acquisition (2,3). This technique (see Fig. 1a), which is known as MRS imaging (MRSI) and was first described for 1 H by Luyten et al. (4), yields much more spatial information at equal SNR (5), as determined by the voxel size and acquisition time (6). To reduce SNR loss from incomplete longitudinal relaxation, T 1 , the TR is extended beyond the actual acquisition-cycle, T C , the time needed to prepare and acquire one transient, as determined primarily by the desired spectral resolution. Since the system "recovers" for (TR-T C ), its duty cycle (DC) is an inherently suboptimal Ͻ100%. The second approach, introduced for 1 H-MRSI by Duyn and Moonen (7), was to maximize the amount of information per unit time by increasing the DC. This was achieved by multiplexing in time, acquiring several T C 's every TR, each from a different slice, as shown in Fig. 1b (8). The problem with this approach is that in order to satisfy spatial coverage and spectral resolution requirements, TR must be longer than the optimum, TR opt , and consequently the SNR is suboptimal.In this paper we extend the approach of 3D-multislab MRI (9) to 1 H-MRSI by multiplexing in space and time, as shown in Fig. 1c, and derive expressions for its gains in the DC and SNR over the current state of the art. We demonstrate that when more than one T C fits into TR opt , slab interleaving is more efficient than either the multislice approach (7) or whole volume of interest (VOI) per TR opt coverage (2,3,10 -15). W...

show abstract

Metabolic imaging of patients with intracranial tumors: H-1 MR spectroscopic imaging and PET.

Cited by 237 publications

References 0 publications

Comparative metabolic profiling of paediatric ependymoma, medulloblastoma and pilocytic astrocytoma

Comparative metabolic profiling of paediatric ependymoma, medulloblastoma and pilocytic astrocytoma

Application of magnetic resonance spectroscopy in the differentiation of high-grade brain neoplasm and inflammatory brain lesions

Optimizing the efficiency of high‐field multivoxel spectroscopic imaging by multiplexing in space and time

Contact Info

Product

Resources

About