Proton MR spectroscopy in gliomatosis cerebri

Two cases of gliomatosis cerebri are presented in which there was markedly decreased N-acetyl aspartate and an elevated lactate-lipid area in the MR proton spectra. Received: 6 September 1999 Accepted: 10 December 1999     

Multivoxel magnetic resonance spectroscopy in gliomatosis cerebri

Gliomatosis cerebri is a rare entity with non-specific clinical and conventional magnetic resonance imaging (MRI) findings; accurate diagnosis is a differential diagnostic challenge. MR spectroscopy has recently been introduced as a useful diagnostic tool for detection of this entity. We present a gliomatosis cerebri case in which we made the radiological diagnosis using the MR spectroscopy findings; the diagnosis was confirmed by subsequent biopsy and histopathologic evaluation. Multivoxel spectroscopy (CSI, PRESS, 1500/135) shows a marked increase in Cho/NAA (6.6), normal to mild increase in Cho/Cr (1.2), and marked decrease in NAA/Cr (0.2) compared with the normally appearing contralateral side (Cho/NAA: 0.8, Cho/Cr: 0.9, NAA/Cr: 1.2).     

Fluid-attenuated inversion-recovery MR imaging of gliomatosis cerebri

Magnetic resonance imaging has been shown to be the most sensitive imaging modality in the assessment of gliomatosis cerebri. Recent studies have shown that fluid-attenuated inversion-recovery (FLAIR) is a valuable MR sequence in the delineation of cerebral pathologies including intra-axial tumors. However, no data are available about the role of this novel technique in the assessment of gliomatosis lesions. The purpose of this study was therefore to evaluate the diagnostic potential of FLAIR MR imaging in patients with suspected gliomatosis cerebri. Seven patients suspected of having lesions of gliomatosis cerebri were examined by T1-weighted spin echo (SE), T2-weighted fast spin echo (FSE), and FLAIR MR imaging with identical slice parameters. T1 and FLAIR were repeated after contrast media administration. Delineation and extent of gliomatosis were the primary parameters of the image analysis. The FLAIR imaging clearly delineated the extent of gliomatosis lesions in all patients. Due to the suppression of cerebrospinal fluid, the delineation was superior to conventional T2-weighted FSE images. Especially the detection and delineation of cortical spread and the infiltration of the corpus callosum was best seen on FLAIR images. The FLAIR MR imaging is a valuable diagnostic modality in the assessment of patients with gliomatosis cerebri. Due to its better delineation of tumor spread, it was found to be the imaging method of choice and should therefore be integrated into the MR imaging protocol of these patients. Received: 28 February 2000/Revised: 16 June 2000/Accepted: 19 June 2000     

Value of diagnosis and differential diagnosis of MRI and MR spectroscopy in gliomatosis cerebri

PURPOSE: The purpose of this study was to characterize gliomatosis cerebri on magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), and to analyze the value of these two techniques in diagnosis and differential diagnosis of gliomatosis cerebri. MATERIALS AND METHODS: MR images of 14 patients with gliomatosis cerebri were reviewed retrospectively; seven of the patients also underwent MRS (single-voxel point-resolved spectroscopy, and chemical-shift imaging point-resolved spectroscopy). Tumorous were confirmed by surgery and biopsy. The distribution, extension and signal features of lesions were assessed, and the MR spectroscopy results were analyzed. RESULTS: Tumors involved at least two lobes of the brain in all patients. Widespread invasion with isointensity or hypointensity on T1-weighted MR images and hyperintensity on T2-weighted images were found while no prominent necrosis, hemorrhage or contrast enhancement was found. All patients who underwent MRS showed elevated Cho/Cr and Cho/NAA levels as well as decreased NAA/Cr ratios in the abnormal areas on T2-weighted images, three of which showed a lactate doublet. Anaplastic lesions had higher Cho/NAA levels in three cases. Abnormality of metabolism was also seen in the margin of the lesion that was normal on T2-weighted images. CONCLUSION: MRI and MRS are valuable techniques for diagnosis and differential diagnosis of gliomatosis cerebri. Combining clinical information and MRI findings, as well as MRS, is crucial for making a definitive diagnosis.     

Proton MR spectroscopy of gliomatosis cerebri: case report of elevated myoinositol with normal choline levels

A 69-year-old woman presented with clinical and imaging findings suspicious for gliomatosis cerebri, later confirmed by biopsy (moderately cellular, infiltrating glioma). Single voxel proton MR spectroscopy (TE 20 and TE 135) and spectroscopic imaging (TE 135) performed at admission showed normal choline, decreased N-acetyl, and elevated myo-inositol levels relative to creatine. The primary conclusion is that in suspected cases of gliomatosis cerebri, myo-inositol/creatine and myo-inositol/N-acetyl should be determined because they may provide evidence of tumor, even though choline/creatine is normal. A corollary to this conclusion is that choline/creatine may be misleading if used to demarcate infiltrating glioma from edema.     

Dynamic contrast-enhanced T2*-weighted MR imaging of gliomatosis cerebri

BACKGROUND AND PURPOSE: MR imaging characteristics of gliomatosis cerebri reiterate the diffuse nature of this tumor but are nonspecific and thus may pose a diagnostic challenge. Because perfusion MR imaging can provide a physiologic map of the microcirculation, we compared the measured relative cerebral blood volume (rCBV) at perfusion imaging with histopathologic findings in gliomatosis cerebri. MR spectroscopic findings were also reviewed. METHODS: Retrospective analysis was performed of conventional and perfusion MR images from seven patients with proved gliomatosis cerebri. The conventional MR images were evaluated for the presence or absence of contrast enhancement, necrosis, and extent of T2-weighted signal intensity abnormality. Dynamic contrast-enhanced T2*-weighted gradient-echo echo-planar images were acquired during the first pass of a bolus injection of gadopentetate dimeglumine. The rCBV was calculated by using nondiffusible tracer kinetics and expressed relative to normal-appearing white matter. Pathologic findings were reviewed in all patients and compared with the MR perfusion data. Multivoxel 2D chemical shift imaging proton MR spectroscopic data were available for three patients and single-voxel data for one patient. RESULTS: Conventional MR images showed diffuse abnormality in all cases and absence of contrast enhancement in all but one case. Average rCBV range was 0.75-1.26 (mean, 1.02 +/- 0.42 [SD]). MR spectroscopic data revealed spectra consistent with presence of tumoral disease. Histopathologic review showed absence of vascular hyperplasia in all specimens. CONCLUSION: The low MR rCBV measurements of gliomatosis cerebri are in concordance with the lack of vascular hyperplasia found at histopathologic examination; thus, perfusion MR imaging provides useful adjunctive information that is not available from conventional MR imaging techniques.     

Computed tomography of gliomatosis cerebri

Gliomatosis cerebri, a rare diffusely infiltrating astrocytoma, was discovered on the postmortem examination of a 22-year-old woman with a 13 year history of seizures. Computed tomography of the brain revealed bifrontal white matter low density changes that were most consistent with a demyelinating or dysmyelinating disorder.     

MR and positron emission tomography with fludeoxyglucose F 18 in gliomatosis cerebri.

A 16-year-old girl presented with a unilateral third nerve palsy and predominant gray matter involvement on MR and positron emission tomography with fludeoxyglucose F 18. These findings were manifestations of gliomatosis cerebri. The antemortem diagnosis was made by partial temporal lobectomy.     

A difficult diagnosis of gliomatosis cerebri

Gliomatosis cerebri, a rare condition, requires clinical, radiological and pathological correlation for diagnosis. Mental and personality changes are the most common presenting symptoms with or without focal neurological signs. The widespread nature of the disease is revealed by CT or MRI. The shape of the brain may be maintained and pathological gross examination may be unremarkable or show hypertrophy without evident tumour. Microscopic examination reveals infiltration of the brain by variably differentiated neoplastic glial cells. We present a patient with gliomatosis cerebri in whom we experienced difficulties with diagnosis. The literature is reviewed and the diagnostic features summarised.     

大脑胶质瘤病磁共振成像结合磁共振波谱成像的诊断价值

目的：探讨磁共振成像（MRI）结合磁共振波谱成像（MRS）对大脑胶质瘤病的诊断价值。方法对15例经活体组织检查或手术病理证实的大脑胶质瘤病患者的临床表现及MRI平扫、增强,MRS影像学资料进行回顾性分析。MRI常规行T1WI、T2WI及FLAIR序列,采用时间飞跃法（TOF）的磁共振血管成像（MRA）,T1WI增强扫描。氢质子MRS采用单体素STEAM序列,并分析N-乙酰天门冬氨酸（NAA）、肌酸（Cr）、胆碱复合物（Cho）等物质峰值改变。结果所有病例均侵犯2个或2个以上脑叶,以颞叶、枕叶、胼胝体、基底节和丘脑等部位侵犯受累常见。病变区T1WI呈低或等低信号、T2WI呈高或混杂高信号、FLAIR上为高信号,未见明显坏死、钙化,受累区域脑组织肿胀,占位效应轻。注射钆喷酸葡胺增强扫描示10例无明显强化、3例斑片状强化、1例结节状强化、1例线状轻度强化。病变区域MRS表现为不同程度NAA降低,NAA/Cr比值降低;Cho上升,Cho/Cr和Cho/NAA的比值上升。结论 MRI结合MRS对大脑胶质瘤病的诊断及鉴别诊断具有临床价值,是目前诊断大脑胶质瘤病的首选影像学方法。     

Magnetic resonance imaging determination of gliomatosis cerebri

Summary Gliomatosis cerebri is a rare condition characterized by diffuse overgrowth of large portions of the brain and spinal cord by glial cells in varying stages of differentiation. The tumor process is primarily an infiltrative, rather than a destructive one. Hence, pre-operative diagnosis by traditional imaging studies, including computed tomography (CT), has been difficult. Magnetic resonance imaging (MRI), with its unique sensitivity for cerebral pathology, is an ideal modality for demonstrating this lesion. We present three cases of gliomatosis cerebri in which high-field MRI clearly delineates the extent of the pathologic process.     

MRI对脑胶质瘤病的诊断价值

目的：探讨MRI对脑胶质瘤病的诊断价值。方法：分析7例脑胶质瘤病的MRI表现。结果：7例胶质瘤病均侵犯2个脑叶或以上，5例侵及大脑深部结构，病变均呈长T1、长T2信号，占位效应不明显，未见明显强化，DWI示部分病灶呈高信号，ADC图呈低信号，且ADC值低于正常脑实质值，MRS波谱示病变区NAA峰明显降低，2例CHO峰明显升高，未见明显LAC峰，病理证实为脑胶质瘤病。结论：MRI是目前诊断脑胶质瘤病的首选影像学诊断方法。     

MR imaging of pseudotumor cerebri

Eleven obese young women with idiopathic pseudotumor cerebri were studied with high-field-strength (1.5 T) MR imaging to demonstrate increased water content in the brains of such patients. Heavily T2-weighted studies were obtained for 10 patients, and balanced (long TRs, short TEs, spin density, proton density) pulse sequences were obtained for four patients. We examined the studies of morphologically normal periventricular white matter and developed a white matter water index to determine if a slight increase in signal was present that could be ascribed to low levels of edema. Comparison was made to an age-matched control group. We also examined five patients with sodium MR imaging. Two of the 11 patients had focal areas of increased signal in their periventricular white matter. Presumably, these are areas of increased edema above the background that could not be detected on the CT scan. The white matter water index for the normal controls was an average of 0.479 (+/- 0.015), while that of the pseudotumor cerebri group was 0.520 (+/- 0.016). This indicates an increase in the white matter water signal. We believe this represents a diffuse low level of edema. These findings are consistent with previous estimates of the increase in brain water in patients with idiopathic pseudotumor cerebri. The patients with focally abnormal proton studies demonstrated similar abnormalities on their sodium studies.     

Diffusion tensor tractography of gliomatosis cerebri: fiber tracking through the tumor

In previous reports, tracts obtained by diffusion tensor (DT) fiber tracking were terminated or deviated by the brain tumors or surrounding edema. There has been no report showing diffusion tensor tractography penetrating through the tumor. A case of glioma is reported, whose DT fiber tract passing through the tumor was observed by changing the threshold of fractional anisotropy.     

Oligodendroglial gliomatosis cerebri: 1H-MRS suggests elevated glycine/inositol levels

Oligodendroglial gliomatosis cerebri is very rare. We describe 42-year-old woman who had low-grade oligodendroglial gliomatosis cerebri confirmed on stereotactic biopsy. The diffuse nature of the tumour was apparent clinically, neurophysiologically, on MRI and on proton magnetic resonance spectroscopy (MRS). She also had an isolated, false-localising partial seventh nerve palsy. MRS, of which there are no previous reports, suggested elevated glycine/inositol levels. This might be explained by the cell lineage from which the tumour arose. Received: 5 January 1999 Accepted: 25 January 1999     

Role of proton magnetic resonance spectroscopy in the diagnosis of gliomatosis cerebri: a unique pattern of normal choline but elevated Myo-inositol metabolite levels

A patient with histologically proven gliomatosis cerebri presented with a normal choline level but a markedly abnormal elevated myo-inositol level on magnetic resonance (MR) spectroscopy. We describe the case presentation, imaging findings (in particular, the unique MR spectroscopic pattern), and their significance regarding the diagnosis of this relatively rare neoplasm.