孤立性肺结节质子MR波谱的初步研究

目的　研究孤立性肺结节氢质子波谱 (1 H MRS)的特征及其代谢物变化规律 ,探讨MRS在孤立性肺结节诊断中的应用价值。方法　应用SiemensVision 1 5T超导MR机对 6 9例孤立性肺结节行常规MR检查和MRS测量 ,观察记录所有孤立性肺结节MRS特征及各代谢物参数值。 1 0例手术标本行MRS检查 ,其结果并与术前MRS结果对照分析。结果　胆碱 (Cho)含量恶性结节组 (2 86±1 89)明显高于炎性结节 (0 87± 0 74 )、结核球 (0 97± 1 0 9)及错构瘤组 (0 4 2± 0 5 3) (P <0 0 1 )。胆碱与肌酸比值 (Cho/Cr)恶性结节组 (1 34± 1 1 3)亦明显高于其他 3组结节 (炎性结节 0 1 7± 0 1 8;结核球 0 4 7± 0 92 ;错构瘤 0 2 8± 0 1 7) (P <0 0 5 )。乳酸含量 (Lac)恶性结节组显著高于其他 3组结节(恶性结节 1 9 4 3± 9 2 1 ;炎性结节 5 70± 1 86 ;结核球 4 2 5± 1 4 3;错构瘤 4 5 3± 1 5 1 ) (P <0 0 0 1 )。 1 0例手术标本MRS检测结果与术前MRS检测结果行配对t检验 ,二者之间差异无统计学意义 (P >0 0 5 )。结论　活体肺结节MRS检测结果是可靠的。Cho升高、Cho/Cr值的增加和出现异常Lac峰是恶性结节的波谱特征 ,有助于良恶性肺结节的鉴别诊断。     

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     

Childhood neuroborreliosis: clinicoradiological correlation

We report the cranial CT and MRI findings in three children with Lyme disease (neuroborreliosis). The neuroimaging findings in children have been rarely reported. We found cranial MRI far superior to cranial CT. Ring-enhancing lesions have been described in acute disseminating encephalomyelitis and multiple sclerosis but not in neuroborreliosis. Although orther infectious and inflammatory diseases cannot be excluded, Lyme disease should be included in the differential diagnosis and put forward as being the most likely diagnosis in the appropriate clinical setting. Gadopentetate dimeglumine is helpful in assessing the response to antibiotic treatment.     

MR imaging in neuroborreliosis of the cervical spinal cord

The central nervous system is involved in 10–20% of cases in Lyme disease. The neurological symptoms, time course of the disease and imaging findings are multifaceted. We report two patients with cervical radiculitis. Magnetic resonance imaging revealed strong enhancement of the cervical nerve roots on contrast-enhanced T1-weighted images. These imaging patterns of borrelia-associated radiculitis have not been reported before. Knowledge of these imaging features may help to diagnose neuroborreliosis, which presents with non-specific symptoms.     

MR波谱在预测前列腺癌转移中的作用

目的 探讨MR波谱(MRS)在预测前列腺癌转移中的价值.方法 65例超声引导下穿刺活检证实的前列腺癌患者,根据临床分期分为未发生转移组(B期和C期)31例和发生骨和(或)淋巴结转移组(D期)34例,通过MRS测定2组患者癌病灶区(胆碱+肌酸)/枸橼酸盐[(Cho +Cre)/Cit]的比值,并比较其差异.同时利用描绘受试者工作特征(ROC)曲线来初步评价MRS在预测前列腺癌发生转移中的效能.结果 未发生转移组和发生转移组患者的前列腺癌区(Cho+Cre)/Cit比值分别为1.3±0.5和2.2±0.6,差异有统计学意义(t=6.38,P＜0.05).利用癌病灶区(Cho+Cre)/Cit的平均比值对肿瘤是否发生转移进行诊断试验,ROC曲线下面积(Az)值为0.87,最佳临界点为1.53,此时诊断的敏感性为94.12%(32/34),特异性为67.74%(21/31),准确性为81.54%(53/65).结论 MRS作为一种无创的MRS检查方法 ,有可能对肿瘤是否发生转移作出预测.     

新生儿缺氧缺血性脑病的MR波谱研究

目的观察足月新生儿缺氧缺血性脑病（HIE）时的脑代谢改变，并探讨其与临床分度及预后的关系。方法以9例无窒息的正常新生儿作为对照，对临床确诊的46例HIE患儿进行MRI及氢质子MR波谱（^1H—MRS）检查，MRS采用单体素及二维多体素化学位移波谱技术。46例HIE临床分度包括轻度25例、中度11例以及重度10例。观察HIE患儿MRS代谢物变化及其与临床分度和预后的关系。结果（1）HIE的典型表现为：乳酸（Lac）峰增高，谷氨酸及谷氨酰复合物α峰（GLx—α）增高及氮-乙酰天门冬氨酸（NAA）峰降低。（2）GLx—α／肌酸及磷酸肌酸（Cr）比值在对照组及HIE轻、中、重度组分别为0．16、0．21、0．64、1．31，GLx—α／Cr比值在对照组及HIE组差异有统计学意义（t=5．01，P〈0．01），且在HIE各组之间差异亦有统计学意义（F=63．29，P〈0．05）。Lac／Cr比值在对照组及HIE轻、中、重度组分别为0．12、0．14、0．19、0．26，该比值在对照组及HIE组差异有统计学意义（t=2．78，P〈0．05），且在HIE各组之间差异亦有统计学意义（F=11．74，P〈0．05）。GLx—α／Cr及Lac／Cr比值与临床分度呈正相关性（r=0．76及0．59，P均〈0．01）。NAA／Cr比值在HIE重度组明显低于中、轻度组。（3）等级相关分析证明GLx—α／Cr及Lac／Cr比值与HIE预后呈负相关关系，尤其是GLx—α／Cr比值相关性更强（相关系数r=-0．83，P〈0．01），可作为评估HIE预后的有效指标。结论 ^1H—MRS技术可无创观察HIE患儿脑代谢改变，观察脑损伤严重程度及预后评估。HIE患儿基底节区GLx—α／Cr比值升高提示预后不良。     

Proton MR spectroscopy of the prostate

PURPOSE: To summarize current technical and biochemical aspects and clinical applications of proton magnetic resonance spectroscopy (MRS) of the human prostate in vivo. MATERIAL AND METHODS: Pertinent radiological and biochemical literature was searched and retrieved via electronic media (medline, pubmed. Basic concepts of MRS of the prostate and its clinical applications were extracted. RESULTS: Clinical MRS is usually based on point resolved spectroscopy (PRESS) or spin echo (SE) sequences, along with outer volume suppression of signals from outside of the prostate. MRS of the prostate detects indicator lines of citrate, choline, and creatine. While healthy prostate tissue demonstrates high levels of citrate and low levels of choline that marks cell wall turnover, prostate cancer utilizes citrate for energy metabolism and shows high levels of choline. The ratio of (choline+creatine)/citrate distinguishes between healthy tissue and prostate cancer. Particularly when combined with magnetic resonance (MR) imaging, three-dimensional MRS imaging (3D-CSI, or 3D-MRSI) detects and localizes prostate cancer in the entire prostate with high sensitivity and specificity. Combined MR imaging and 3D-MRSI exceed the sensitivity and specificity of sextant biopsy of the prostate. When MRS and MR imaging agree on prostate cancer presence, the positive predictive value is about 80-90%. Distinction between healthy tissue and prostate cancer principally is maintained after various therapeutic treatments, including hormone ablation therapy, radiation therapy, and cryotherapy of the prostate. CONCLUSIONS: Since it is non-invasive, reliable, radiation-free, and essentially repeatable, combined MR imaging and 3D-MRSI of the prostate lends itself to the planning of biopsy and therapy, and to post-therapeutic follow-up. For broad clinical acceptance, it will be necessary to facilitate MRS examinations and their evaluation and make MRS available to a wider range of institutions.     

Proton MR spectroscopy in patients with pyogenic brain abscess: MR spectroscopic imaging versus single-voxel spectroscopy

Purpose

Single-voxel spectroscopy (SVS) has been the gold standard technique to diagnose the pyogenic abssess. Two-dimensional magnetic resonance spectroscopic imaging (MRSI) is able to provide spatial distribution of metabolic concentration, and is potentially more suitable for differential diagnosis between abscess and necrotic tumors. Therefore, the purpose of this study was to evaluate the equivalence of MRSI and SVS in the detection of the metabolites in pyogenic brain abscesses.

Materials and methods

Forty-two patients with pyogenic abscesses were studied by using both SVS and MRSI methods. Two neuroradiologists reviewed the MRS data independently. A κ value was calculated to express inter-reader agreement of the abscesses metabolites, and a correlation coefficient was calculated to show the similarity of two spectra. After consensus judgment of two readers, the binary value of metabolites of pyogenic abscesses (presence or absence) was compared between SVS and MRSI.

Results

The consistency of spectral interpretation of the two readers was very good (κ ranged from 0.95 to 1), and the similarity of two spectra was also very high (cc = 0.9 ± 0.05). After consensus judgment of two readers, the sensitivities of MRSI ranged from 91% (acetate) to 100% (amino acids, succinate, lactate, lipid), and the specificities of MRSI were 100% for detecting all metabolites with SVS as reference.

Conclusion

SVS and MRSI provide similar metabolites in the cavity of pyogenic brain abscess. With additional metabolic information of cavity wall and contralateral normal-appearing brain tissue, MRSI would be a more suitable technique to differentiate abscesses from necrotic tumors.     

恶性胶质瘤的二维氢质子磁共振波谱研究

研究脑恶性胶质瘤的二维氢质子磁共振波谱(2D1H -MRS)特征及其代谢物变化规律。材料和方法 :经病理学证实的恶性胶质瘤14例(男性8例 ,女性6例 ,年龄19～72岁) ,年龄相近正常对照组15例 ,使用1.5TMRI成像仪 ,PRESS序列 ,TR/TE=1000ms/144ms ,多体素相位矩阵 :16×16 ,FOV :24cm。完成扫描后用随机软件包FuncTool进行分析 ,观察正常对照组(作为外参照)、病例组病灶周边、病变区及对侧正常区(内参照)各主要代谢物变化情况。结果 :14例胶质瘤按WHO标准分类Ⅲ级6例 ,Ⅳ级8例 ,肿瘤实体区NAA/Cho、NAA/Cr、NAA/(Cho +Cr)分别为0.39±0.11 ,1.09±0.38 ,0.28±0.06 ,较正常参照区降低且具显著性差异(p<0.05) ;Cho/Cr和Lac/Cr分别为3.05±1.44 ,0.35±0.59 ,均较参照区升高 ,前者p<0.05 ,后者无统计学差异(p>0.05) ;结合多体素波谱图观察提示恶性胶质瘤Cho升高、NAA下降和出现异常Lac峰 ,同时可显示肿瘤周边区域的Cho升高等异常。结论 :Cho升高、NAA下降和出现异常Lac峰是恶性胶质瘤的主要波谱表现。2D 1H -MRS可检测胶质瘤MRI所示病灶以外区域的代谢异常 ,此对鉴别诊断、立体定向活检和制定治疗方案等有较高临床应用价值     

肝细胞急性坏死与凋亡的磁共振波谱研究

 目的 建立大鼠肝细胞坏死和凋亡的动物模型,将不同时间点的MRS检测结果与病理学所见进行对照研究,以评估MRS检测及鉴别肝细胞凋亡和坏死的能力与价值.方法 72只S-D大鼠随机分成假手术对照组、右侧肝动脉与门静脉分支均结扎组(HA+PV组)和单独右侧门静脉分支结扎组(PV组),实验组各分成4个亚组,每个亚组6只,分别于术后3 h、12 h、24 h、72 h行普通MRI和单体素PRESS 35序列MRS,得到肝右叶与左叶各代谢物浓度,以及肝右叶内代谢物相对比值.结果 HA+PV及PV组术后3 h,少量肝细胞发生坏死与凋亡时,肝右叶Lip-Lac较左叶相比即有明显增高,随着凋亡与坏死细胞增多,Lip-Lac增高更加明显.术后12 h肝右叶Cho较左叶相比出现降低,也随时间延长逐渐明显;肝右叶Lip-Lac/Cho比值在HA+PV及PV组术后3 h均有增高,以PV 3 h组增高更显著.结论 凋亡与坏死组织在1H MRS中都有Lip-Lac增加,Cho降低.肝细胞凋亡后早期,Lip-Lac/Cho比值增高较坏死明显,采用Lip-Lac/Cho比值对鉴别早期肝细胞坏死与凋亡具有一定意义.     

Proton MR spectroscopy of cerebral gliomas at 3 T: spatial heterogeneity, and tumour grade and extent

This study aimed to evaluate the usefulness of proton MR spectroscopic imaging ((1)H-MRSI) at 3 T in differentiating high- from low-grade gliomas, and tumour from necrosis, oedema or normal tissue. Forty-four patients with brain gliomas and four with meningiomas were retrospectively reviewed. The normalised metabolites choline (nCho), N-acetylaspartate (nNAA), creatine (nCr) and lactate/lipids (nLL), and the metabolite ratios Cho/NAA, NAA/Cr and Cho/Cr were calculated. Necrotic-appearing areas showed two spectroscopic patterns: "necrosis" with variable nCho and high nLL, and "cystic necrosis" with variable nLL or nonevident peaks. Peri-enhancing oedematous-appearing areas showed three spectroscopic patterns ("tumour" with abnormal Cho/NAA, "oedema" with normal Cho/NAA and "tumour/oedema" with normal nCho and abnormal Cho/NAA) in gliomas, and one ("oedema") in meningiomas. Peri-enhancing or peri-tumour normal-appearing areas showed two patterns ("infiltrated" with abnormal nCho and/or Cho/NAA and "normal" with normal spectra) in gliomas and one ("normal") in meningiomas. Discriminant analysis showed that classification accuracy between high- and low-grade glioma masses was better with normalised metabolites or all parameters together than metabolite ratios and that among peri-enhancing areas was much better with normalised metabolites. The analysis of spatial distribution of normalised metabolites by 3-T (1)H-MRSI helps to discriminate among different tissues, offering information not available with conventional MRI.     

MR spectroscopy in a cervical abscess

Abstract MR spectroscopy (MRS) has been used to analyse noninvasively tissues at a molecular level. Hydrogen and phosphorus MRS have been used for characterisation of intracranial solid and cystic masses, gynaecological tumours and lymph nodes. We report a cystic, tick-walled mass in the soft tissues of the neck. Single-voxel proton MRS revealed a prominent acetate peak at 1.92 ppm and a diagnosis of abscess was suggested. At operation a pyogenic neck abscess was confirmed, with culture of the pus.     

MR波谱分析对前列腺癌诊断效能的研究

目的 以前列腺六分区法为基础,评价MRS对前列腺痛的诊断效能.方法 110例行MR前列腺检查的患者中前列腺癌54例,非前列腺癌56例,以经直肠穿刺活检病理结果作为金标准,计算前列腺MRS各体素内的(且H碱+肌酸)/枸橼酸盐(CC/C)的比值并采用秩和检验进行比较,计算六分区内阳性体素所占的比例(阳性体素比,PVR),采用ROC分析判断单个体素代谢物比值及分区内阳性体素比的诊断效能.结果 来源于癌区的体素1673个,非癌区体素2426个.癌区和非癌区体素的CC/C中位数分别为2.137和0.600,差异有统计学意义(Z-41.7,P<0.01).以单个体素CC/C比值0.911为临界点,诊断前列腺癌的敏感度为81.4%(1362/1673),特异度为83.1%(2018/2426),准确度为82.4%[(1362+2018)/4099].癌区和非癌区的PVR中位数分别为1和0,差异有统计学意义(Z=-11.7,P<0.01).以分区内PVR值0.519为临界点时,诊断前列腺癌的敏感度77.5%(148/191),特异度76.9%(247/321),准确度为77.1%[(148+247)/512].结论 通过确定单个体素CC/C比值及六分区内PVR的临界值,MRS有助于前列腺癌的量化诊断.     

自闭症的常规MRI和1H-MRS表现

目的 探讨常规MR成像和1H MR波谱(MRS)在自闭症诊断中的价值.资料与方法 回顾性分析12例自闭症患者的全脑常规MR扫描及其中8例患者额叶和海马的多体素2D 1H MR波谱扫描表现.结果 常规MR扫描发现3例患者的顶叶白质在FLAIR上出现斑片状高信号.1H MRS分析发现5例患者额叶的NAA/Cho明显下降(NAA/Cho<1),其中1例患者的左侧额叶出现Lac峰;另外有2例患者海马的NAA/Cho出现下降(NAA/Cho<1).结论 常规MR成像和1H MRS可发现部分自闭症患者脑组织异常.     

颅内结核瘤的质子MR波谱研究

目的探讨质子MR波谱(1H-MRS)对颅内结核瘤的诊断价值。资料与方法回顾性分析26例颅内结核瘤患者术前或接受治疗前的1H-MRS表现,1H-MRS采用多体素2D1H-MRS,点分辨表面线圈法(PRESS)。比较结核瘤病灶实质和对侧正常脑组织的胆碱(Cho)、肌酸(Cr)、N-乙酰天门冬氨酸(NAA)、Cho/Cr,Cho/NAA、NAA/Cho差异有无统计学意义,观察有无脂质(Lip)峰或氨基酸峰(AAs)出现。结果颅内结核瘤实质部分Cho较对侧升高,差异无统计学意义(颅内结核瘤和对侧正常脑组织Cho分别为366.7±137.4,325.4±126.4,P>0.05),Cr、NAA、NAA/Cho低于对侧,差异有统计学意义(颅内结核瘤和对侧正常脑组织Cr分别为163.6±74.1,300.1±140.5,P<0.01;NAA分别为239.4±96.6,475.3±244.7,P<0.01;NAA/Cho分别为0.74±0.35,1.56±0.60,P<0.01),Cho/Cr、Cho/NAA高于对侧,差异有统计学意义(颅内结核瘤和对侧正常脑组织Cho/Cr分别为2.05±0.63,1.14±0.38,P<0...     

Proton magnetic resonance spectroscopy of a patient with Gerstmann-Straussler-Scheinker disease

A 23-year-old woman with Gerstmann-Straussler-Scheinker disease (GSS) was investigated by ¹H-magnetic resonance spectroscopy (¹H-MRS). She developed gait ataxic at 22 years. The diagnosis was confirmed by DNA analysis showing a proline-to-leucine point mutation at codon 102 of the prion protein. On ¹H-MRS, she showed a remarkable reduction of the N-acetylaspartate/creatine ratio in the frontal lobe, cerebellar hemisphere and vermis and putamen. MRI revealed mild atrophy of the cerebellar hemispheres and vermis and cerebral cortex, but single-photon emission computed tomography (SPECT) with ^99mHMPAO showed normal perfusion in the cerebellum. The imaging studies suggest that MRS might be superior to MRI or SPECT for detection of early neuronal degeneration. Received: 31 August 1999/Accepted: 10 December 1999     

Proton magnetic resonance spectroscopy in brain tumours: clinical applications

Parallel to the rapid development of clinical MRI, MR spectroscopy (MRS) has, after starting as an analytical tool used in chemistry and physics, evolved to a noninvasive clinical examination. Most common neuroradiological diagnostic indications for MRS are functional inborn errors, neonatal hypoxia, ischaemia, metabolic diseases, white matter and degenerative diseases, epilepsy, inflammation, infections and intracranial neoplasm. Compared to CT and MRI, well-established morphological diagnostic tools, MRS provides information on the metabolic state of brain tissue. We review the clinical impact of MRS in diagnosis of tumours and their differentiation from non-neoplastic lesions. Received: 3 April 2000 Accepted: 1 September 2000     

1H MR spectroscopy of the basal ganglia in childhood: a semiquantitative analysis

Proton MR spectra of the basal ganglia were obtained from 28 patients, 24 male and 14 female, median age 16.3 months (5 weeks to 31 years). They included 17 patients with normal MRI of the basal ganglia without metabolic disturbance (control group) and 11 patients with various metabolic diseases: one case each of high serum sodium and high serum osmolarity, cobalamin C deficiency, Leigh disease, Galloway-Mowat syndrome, Pelizaeus-Merzbacher disease, hemolytic-uremic syndrome and Wilson disease and two cases of Alagille syndrome and methylmalonic acidemia with abnormal MRI of the basal ganglia or blood or urine analysis (abnormal group). The MR spectrum was measured by using STEAM. The MR-visible water content of the region of interest was obtained. Levels of myoinositol, choline, creatine and N -acetylaspartate were measured using a semiquantitative approach, with absolute reference calibration. In the control group, there was a gradual drop of water content over the first year of life; N -acetylaspartate, creatine and myoinositol levels showed no significant change with age, in contrast to the occipital, parietal and cerebellar regions. Choline showed a gradual decrease for the first 2 years of life and then remained fairly constant. In the abnormal group the water content was not significantly different. N -Acetylaspartate was decreased in patients with high serum sodium and high serum osmolarity, cobalamin C deficiency, Leigh disease and one case of methylmalonic acidemia. Decreased creatine was also found in Leigh disease, and decreased choline in Galloway-Mowat syndrome and Wilson disease. Myoinositol was elevated in the patient with abnormally high serum sodium, and decreased in the hemolytic-uremic syndrome. Received: 31 January 1997 Accepted: 31 January 1997     

Proton MR spectroscopy in idiopathic spasmodic torticollis

Single-voxel proton magnetic resonance spectroscopy (¹H-MRS), localised to the basal ganglia, was used to determine changes in metabolite levels in idiopathic spasmodic torticollis (IST). We examined nine patients and 13 healthy subjects. The mean values ( ± SD) of peak area ratios were: IST: N-acetyl-aspartate (NAA)/choline-containing compounds (Cho) 1.79 ± 0.39, NAA/creatine and phosphocreatine compounds (Cr) 1.61 ± 0.38, Cho/Cr 0.91 ± 0.19; controls: NAA/Cho 2.07 ± 0.35, NAA/Cr 1.82 ± 0.31, Cho/Cr 0.89 ± 0.12. Statistical analysis showed that NAA/Cho and NAA/Cr were significantly lower in patients than in controls (P = 0.0304 and 0.0431, respectively). These results indicate a reduction in NAA, and suggest striatal involvement in the pathogenesis IST. Received: 8 October 2000 Accepted: 4 December 2000     

儿童神经元蜡样质脂褐素沉积病的MRI及MRS表现

目的：分析婴儿型和晚期婴儿型神经元蜡样质脂褐素沉积病（NCL）的MRI、磁共振波谱（^1H—MRS）表现。方法：对2例婴儿型和8例晚期婴儿型NCL患儿行磁共振平扫和磁共振波谱检查。总结分析各种特征性影像表现及N-乙酰天门冬氨酸（NAA）、总肌酸（Cr）、胆碱复合物（Cho）、NAA／Or、Cho／Cr比值的变化规律。结果：10例患儿都表现为逐渐进展的脑萎缩,婴儿型以大脑萎缩为早期表现,晚期婴儿型以小脑萎缩为早期表现。2例婴儿型病例及病史4～5年的晚期婴儿型患儿可见大脑半球白质的异常高信号,脑室旁白质最为明显。婴儿型病例见双侧丘脑和基底节核团T2WI低信号。8例发现颅骨板障明显增厚。磁共振波谱显示随着病程延长,晚期婴儿型病例的NAA／Cr比值逐渐降低,Cho／Cr值未见明显变化。婴儿型病例末观测到NAA峰,Cho／Cr水平降低,肌醇（mi）水平明显增高。结论：MRI和^1H—MRS可以敏感地发现婴儿型和晚期婴儿型患儿脑内的异常改变9有助于NCL的诊断和分型,并可以评价疾病的严重程度,监测病情变化。