Objective To evaluate proton MR spectroscopy (1H-MRS) for detection of the motor cortex and adjacent brain in amyotrophic lateralsclerosis (ALS) patients with apparent upper motor neuron involvement after olfactory ensheathing cells(OECs) transplantation. Methods From December 2004 to February 2005, 7 patients with clinically definite ALS who could safely undergo MRS were admitted into the perspective study. The neurological status, ALS functional rating scale (ALSFRS), EMG, and 1H-MRS taken before and 2 weeks after operationswere carefully analyzed. The NAA/Cr and Cho/Cr ratios were measured in the cerebral peduncle,genu and posterior limb of the internal capsule, corona radiata and precentral gyrus. Results The ALSFRS in 2 cases mproved obviously whose ALSFRS increased from 30 to 33 and from 29 to 34 respectively. And 5 cases remained stable 2 weeks after OECs transplantation. Statistical analyses for all seven cases showed both theNAA/Cr and Cho/Cr ratios decreased, but in the two cases with ALSFRS improvement the NAA/Cr increased in the certain anatomic position which confirmed the neurological and EMG findings. Conclusion The proton MR spectroscopy is a suitablenoninvasive measure for ALS evaluation. The preliminary study suggests that twoof the seven ALS cases improved apparently shortterm after OECs transplantation. More patients are required for the clinical study and longer followup duration is needed for future research.
Objective To summarize applications and research progress of common magnetic resonance imaging lipid detection techniques in abdomen and pelvis. Method The latest domestic and foreign research literatures related to the applications and research progress of common magnetic resonance imaging lipid detection techniques in the abdomen and pelvis in recent years were collected and reviewed. Results The fat-selective spectral-spatial imaging, 1H-magnetic resonance spectroscopy (1H-MRS), and Dixon & IDEAL are three main magnetic resonance imaging lipid detection techniques, and they can estimate the fat content in the normal tissues and lesions noninvasively and longitudinally, which make the ectopic fat-induced diseases’ early diagnosis, treatment and follow-up possible. Conclusion Magnetic resonance imaging lipid detection techniques have obvious clinical values in quantitative measurement of fat content, and each method gets its own advantage, especially modified Dixon, which is more convenient and accurate and shows an enormous potential in clinical practice.
ObjectiveTo investigate the diagnostic value of spectral saturation inversion recovery, gradient-echo chemical shift MRI， and proton magnetic resonance spectroscopy in quantifying hepatic fat content. MethodsConventional T1-weighted and T2-weighted scanning (without fat saturation and with fat saturation)， gradient-echo T1W in-phase （IP） and opposedphase （OP） images and 1H-MRS were performed in 31 healthy volunteers and 22 patients who were candidates for liver surgery. Signal intensities of T1WI amp; T1WIFS (SInonfat1, SIfat1), T2WI amp; T2WI-FS (SInonfat2, SIfat2), and IP amp; OP (SIin, SIout) were measured respectively, the relative signal intensity one (RSI1), relative signal intensity two (RSI2)， and fat index (FI) were calculated. Peak values and the area under peak of 1H-MRS were measured, and the relative lipid content of liver cells (RLC ) were calculated. Twenty-two patients accepted liver resection and histological examination after MRI scanning, the proportion of fatty degenerative cells were calculated by image analysis software. Results①Hepatic steatosis group showed higher average values of RSI1, FI， and RLC to non-hepatic steatosis group (Plt;0.05), while there was no significant difference in RSI2 between two groups (Pgt;0.05). ②There was a statistical significant difference in RLC among different histopathological grades of hepatic steatosis, and RLC increased in parallel with histopathological grade (Plt;0.05).There was no significant difference in RSI2, RSI1, and FI among different histopathological grades, although the latter two had a tendency of increasing concomitant with histopathological grade (Pgt;0.05). ③The values of FI and RLC were positively correlated with the PFDC （r=0468, P=0.027； r＝0771， Plt;0.000 1）, while they were not in RSI1 and RSI2 (r=0.411, P=0.057； r=0.191, P=0.392). ConclusionsSPIR, Gradient-echo chemical shift MRI and 1H-MRS can help to differentiate patients with hepatic steatosis from normal persons, the latter also can help to classify hepatic steatosis. In quantifying hepatic fat content, 1H-MRS is superior to gradient-echo chemical shift MRI, while SPIR’s role is limited.
Objective To summarize the principle and application of functional MR imaging of pancreatic carcinoma and chronic mass-forming type pancreatitis. Methods Articles about diffusion-weighted imaging (DWI), magnetic resonance spectrum imaging (MRSI) and dynamic contrast-enhanced MR imaging of pancreatic carcinoma and chronic pancreatitis were reviewed and analyzed. Results Functional MR imaging could reflected the differences in molecules diffusion, metabolism and tissue perfusion between pancreatic carcinoma and chronic pancreatitis. Conclusion As a non-invasive protocol, functional MR imaging can provide useful information in differential diagnosis between chronic mass-forming type pancreatitis and pancreatic carcinoma.
ObjectiveTo compare the effectiveness of magnetic resonance spectroscopy (MRS) and Dynamic Contrast-enhancement (DCE-MRI) with 1.5 T MR scanner in diagnosing prostate cancer. MethodsFrom April 2011 to December 2012, based on the results of biopsy, we measured 216 regions of interest (ROIs) in images of MRS and DCE-MRI, comprised of 131 ROIs from cancer zone and 85 ROIs from non-cancer zone. The data were analyzed with statistical methods, including receiver operating characteristic (ROC) curve. ResultsThere were significant differences between the malignant group and the benign group (P<0.05) in Cit integral, Cho integral, CC/Cit ratio, the type of time-signal intensity curve, initial value, enhancement rate and ratio of enhancement. According to ROC curve, the area under curve (AUC) of CC/Cit and enhancement rate was 0.853 and 0.719, respectively. AUC of time to peak, time difference, enhancement rate and Cit integral was lower than 0.400. The optimal operating point (OOP) of CC/Cit was 0.775, with a specificity of 0.85 and a sensitivity of 0.79, and the AUC was 0.853. The OOP of the ratio of enhancement was 60.89, with a specificity of 0.66 and a sensitivity of 0.71, and the AUC was 0.719. ConclusionMRS is more sensitive and specific than DCE-MRI to diagnose prostate cancer when an 1.5 T MR scanner is used. On the other hand, MRS is susceptible to interference, but DCE-MRI can make up for these deficiencies.
ObjectiveTo explore the application value of MRS combined with VEEG on the surgical treatment of temporal lobe epilepsy. MethodsThere were 31 males and 20 females, age between 4 and 62 years.Their illness duration ranged from 4 to 10 years.The clinical manifestations showed complex partial seizure in 10 cases, secondary generalized seizure in 12 and generalized tonic-clonic seizure in 29. Based on their results of clinical manifestations, MRS and VEEG results, all the patients underwent anterior temporal lobectomy(including the most parts of the hippocampus and amydala). ResultsThe follow-up of 1~3 years after the operation showed seizure free in 36 cases(Engle Ⅰ), and significant improvement in 11(Engle Ⅱ), no improvement in 4 cases(Engle Ⅳ). The overall effective rate was 92.16%. ConclusionsMRS combined with VEEG has significant localization value for temporal lobe epilepsy. The prognosis of postoperative result is quiet good to the patient of typical temporal lobe epilepsy after anterior temporal lobectomy.
ObjectiveTo investigate the feasibility of proton magnetic resonance spectroscopy (1H-MRS) imaging, by which to quantitatively analyze liver fat content for therapeutic evaluation of fatty liver at 3.0 T MRI. MethodsTwenty-six patients who diagnosed with fatty liver were examined with proton MRS at Siemens Trio Tim 3.0 T MRI before treatment and 3, 6 months after treatment, respectively. The water peak, fat peak, water peak area, and fat peak area were detected, and the relative lipid content 1 (RLC1) and relative lipid content 2 (RLC2)were calculated. Fatty liver index (FLI) was referred to the standard which was calculated from triglycerides (TG), gammaglutamyl-transferase (GGT), waist circumference, and body mass index. ResultsThere were significantly different differences of RLC1 and RLC2 among before treatment and 3, 6 months after treatment (Plt;0.05). Compared with before treatment, the RLC1 and RLC2 values significantly decreased on month 3 or 6 after treatment (Plt;0.05). There were positive correlation between RLC1 or RLC2 and FLI (r=0.476, Plt;0.00; r=0.475, Plt;0.001). The intraclass correlation coefficient was more than 0.75 before treatment, the repeatability was better. ConclusionsProton MRS can quantitatively measure liver fat content. It can be reliably used for dynamic monitoring the therapeutic effects for fatty liver. Proton MRS is accurate, and has a good clinical application in dynamically monitoring the progression of fatty liver and evaluating the therapeutic effects of various treatments.
摘要:目的: 探讨磁共振波谱(MRS)对鉴别桥小脑角神经鞘瘤与脑膜瘤的价值。 方法 :对8例神经鞘瘤和8例脑膜瘤病例进行MRI平扫和增强扫描,并采用点分辨波谱序列(PRESS,TR/TE=2000/136ms)进行单体素波谱分析。从事磁共振诊断专业的医师根据肿瘤的MRI及MRS表现特征进行鉴别诊断。 结果 :尽管多数神经鞘瘤(5/8)和脑膜瘤(6/8)具有典型的MRI表现特征并仅经MRI即可得到正确鉴别,但部分病例(5/16)为不典型表现者,如脑膜瘤呈长T1长T2信号并伴有囊变,以及神经鞘瘤呈等信号、均匀强化且不伴有囊变或内听道扩大者,鉴别诊断困难。MRS显示脑膜瘤的胆碱/肌酸比值(Cho/Cr)(2.74±1.47)略高于神经鞘瘤(2.70±1.21),但差异无统计学意义。丙氨酸(Ala)在脑膜瘤中的出现率(4/8)显著高于神经鞘瘤(0/8)(Plt;0.05),谷氨酸盐/谷氨酰胺(Glx)在脑膜瘤中的出现率(5/8)也高于神经鞘瘤(2/8);而肌醇(Ins)在神经鞘瘤中的出现率(4/8)高于脑膜瘤(2/8)。结合MRS表现,在MRI上尚难鉴别的病例可被明确诊断,并与最终病理结果相符。 结论 : MRI有助于多数桥小脑角神经鞘瘤与脑膜瘤的鉴别诊断,但对不典型病例有一定局限性;MRS对不典型病例的鉴别具有重要的参考价值。Abstract: Objective: To explore the value of magnetic resonance spectroscopy (MRS) in the differentiation of neurinoma and meningioma in the cerebellopontine angle. Methods : 16 cases, including 8 cases of meningiomas and 8 cases of neurinomas, underwent MRI (plan and gadoliniumenhanced scan) and singlevoxel proton MRS (PRESS series, TR/TE=2000/136ms). MRI and MRS results were reviewed and differential diagnoses were made by professional radiologists. Results : Although most cases (11/16) were typical and clearly classified on MRI, atypical cases were also observed, such as meningioma of long T1/T2 signal intensity with small cystic foci, and neurinoma of isointensity and homogenous enhancement without cystic change or enlargement of internal acoustic meatus. The choline to creatine ratio (Cho/Cr) of meningioma (2.74±1.47) was higher than that of neurinoma (2.70±1.21), however the difference was not significant (Pgt;0.05). Alanine was observed in 4/8 meningiomas but none of neurinomas (Plt;0.05), and glutamine/glutamate was more frequently visualized in meningiomas (5/8) than in neurinomas (2/8), whilemyoinositol was more frequently observed in neurinomas (4/8) than in meningiomas (2/8). With MRS, cases difficult to differentiate were clearly and correctly classified. Conclusion : Although most CPA neurinomas and meningiomas can be diagnosed by MRI, MRS is useful for the differential diagnosis of atypical cases.