共查询到20条相似文献,搜索用时 31 毫秒
1.
《European journal of radiology》2014,83(12):2196-2202
BackgroundThe diffusion tensor imaging (DTI) parameters of the cervical spinal cord (CSC) changes with age. However, previous studies only examined specific CSC areas.ObjectivesTo analyze the DTI parameters in all intervertebral space levels of the whole normal CSC and to study the impact of age on these parameters in a Chinese population.MethodsThirty-six healthy subjects aged 20–77 years were recruited. DTI parameters were calculated for gray matter (GM) and white matter (WM) funiculi in all the CSC intervertebral spaces (C1/2-C6/7). Age-related changes of DTI parameters were analyzed for the GM and WM funiculi.ResultsFractional anisotropy (FA) and mean diffusivity (MD) were lower in GM than in WM. MD and FA values were lower in the WM in the lower CSC compared with the upper CSC (all P < 0.05), but no difference was observed in GM. In ventral funiculi, MD increased with age, while FA decreased (all P < 0.001). In lateral and dorsal funiculi, MD and FA decreased with age (all P < 0.001). In GM, MD and FA decreased with age (all P < 0.001). Significant age-related changes were observed in FA and MD from GM and WM funiculi. FA was correlated with age in all funiculi (ventral: r = −0.733; lateral: r = −0.468; dorsal: r = −0.607; GM: r = −0.724; all P < 0.01).ConclusionImportant changes in MD and FA were observed with advancing age at all levels of CSC in Chinese patients. DTI parameters may be useful to assess CSC pathology, but the influence of age and segments need to be taken into account in diagnosis. 相似文献
2.
Ohgiya Y Oka M Hiwatashi A Liu X Kakimoto N Westesson PL Ekholm SE 《European radiology》2007,17(10):2499-2504
Our purpose was to evaluate the ability of diffusion tensor imaging (DTI) to characterize cervical spinal cord white matter
(WM) in patients with multiple sclerosis (MS). DTI were obtained in 21 MS patients and 21 control subjects (CS). Regions of
interest (ROIs) were placed at C2/3, C3/4, and C4/5 within the right, left, and dorsal (WM) to calculate fractional anisotropy
(FA) and the apparent diffusion coefficient (ADC). Measurements in plaques and normal-appearing white matter (NAWM) of MS
patients were compared with mean FA and ADC of WM in CS. FA was significantly lower in all regions in MS patients than in
CS. ADC was significantly higher in all regions in MS patients than in CS except for in the dorsal WM at C2/3 and the bilateral
WM at C4/5. The mean FA was 0.441 for plaques and 0.542 for NAWM, as compared with 0.739 in CS. The mean ADC was 0.810 × 10−3 mm2/s for plaques and 0.722 × 10−3 mm2/s for NAWM, as compared with 0.640 ×10−3 mm2/s for CS. FA and ADC showed significant differences between plaques, NAWM and control WM(P < 0.01). 相似文献
3.
Sijens PE Irwan R Potze JH Mostert JP De Keyser J Oudkerk M 《European radiology》2005,15(8):1686-1693
Primary progressive multiple sclerosis (ppMS; n=4) patients and controls (n=4) were examined by 1H magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI) in order to map choline (Cho), creatine and N-acetylaspartate (NAA), the fractional anisotropy (FA) and the apparent diffusion constant (ADC). After chemical shift imaging (point-resolved spectroscopy, repetition time/echo time 1,500 ms/135 ms) of a supraventricular volume of interest of 8×8×2 cm3 (64 voxels) MRS peak areas were matched to the results of DTI for the corresponding volume elements. Mean FA and NAA values were reduced in the ppMS patients (P<0.01, both) and the ADC increased (P<0.02). The spatial distribution of NAA showed strong correlation to ADC in both ppMS patients and controls (r =–0.74 and r= –0.70; P<0.00001, both), and weaker correlations to FA (r=0.49 and r=0.41; P<0.00001, all). FA and ADC also correlated significantly with Cho in patients and controls (P<0.00001, all). The relationship of Cho and NAA to the ADC and the FA and thus to the content of neuronal structures suggests that these metabolite signals essentially originate from axons (NAA) and the myelin sheath (Cho). This is of interest in view of previous reports in which Cho increases were associated with demyelination and the subsequent breakdown of neurons. 相似文献
4.
Itaru Adachi Oliver Gaemperli Ines Valenta Tiziano Schepis Patrick T. Siegrist Valerie Treyer Cyrill Burger Koichi Morita Philipp A. Kaufmann 《Journal of nuclear cardiology》2007,14(5):698-705
Background Factor analysis (FA) is an established method for separating myocardium from blood pool by use of oxygen 15-labeled water
and positron emission tomography for analyzing myocardial blood flow (MBF). Conventional FA methods generating images from
sinograms (sinoFA) are time-consuming, whereas FA can be performed on the reconstructed images (reconFA) in a fraction of
time. We validated the MBF values obtained by reconFA versus sinoFA.
Methods and Results In 23 volunteers (mean age, 26.6±3.4 years) MBF was calculated from sinoFA and reconFA and blindly reanalyzed 1 month later
by the same observer. Intraobserver agreement and reconFA-versus-sinoFA agreement were assessed according to Bland and Altman
(BA). Reproducibility proved excellent for global sinoFA (r=0.968; P<.001; BA limits, −0.617 to 0.676 mL·min−1·g−1) and slightly superior for reconFA (r=0.979; P<.001; BA limits, −0.538 to 0.558 mL·min−1·g−1), with wider limits of agreement for segmental MBF from sinoFA (r=0.777; P<.001; BA limits, −1.676 to 1.656 mL·min−1·g−1) and reconFA (r=0.844; P<.001; BA limits, −1.999 to 1.992 mL·min−1·g−1). In addition, sinoFA and reconFA showed excellent correlation (r=0.975, P<.001) and agreement (BA limits, −0.528 to 0.648 mL·min−1·g−1) for global and segmental values (r=0.955; P<.001; BA limits, −1.371 to 1.491 mL·min−1·g−1).
Conclusions Use of reconFA allows rapid and reliable quantitative MBF assessment with O-15-labeled water.
This study was supported by a grant from the Swiss National Science Foundation (professorship grant PP00A-114706). 相似文献
5.
IntroductionTo evaluate the feasibility of testis diffusion tensor imaging (DTI), to determine normative apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values and to assess the efficacy of DTI in characterizing testicular pathology.Materials and methodsFifty-six men underwent MRI of the scrotum, including DTI. Parametric and non-parametric statistical tests were used to compare the ADC and FA between the cranial, middle and lower thirds of normal testis and between the bilateral testicular thirds. Comparison between the ADC and FA of normal testis, malignant and benign testicular lesions was performed.ResultsNo significant differences of the ADC and FA in normal testis between the cranial, middle and lower thirds and between the bilateral testicular thirds were found. ADC was significantly lower in malignancies compared to normal testis (P = 0.006) and benign testicular lesions (P = 0.006). FA was significantly higher both in malignancies (P = 0.001) and benign lesions (P < 0.001) compared to normal testis. FA in malignancies did not differ from FA in benign lesions (P = 0.221)ConclusionsThis study shows the feasibility of testis DTI. Both ADC and FA significantly differ between testicular lesions and normal testis, although FA did not show an incremental diagnostic value compared to ADC in lesion differentiation. 相似文献
6.
Introduction Polymicrogyria (PMG), a neuronal migration disorder, commonly manifests as a seizure disorder. The aim of this study was to look for the abnormalities in the underlying white matter using diffusion tensor imaging (DTI) that appeared normal on conventional magnetic resonance imaging (MRI) in patients with PMG.Methods DTI was performed in three patients with PMG and eight age- and sex-matched healthy controls. Fractional anisotropy (FA) and mean diffusivity (MD) values were calculated for the cortex and adjoining subcortical white matter in both controls and patients.Results We observed a significantly decreased mean FA value with no significant change in the MD value in subcortical white matter underlying polymicrogyric cortex (FA=0.23±0.04, MD=1.0±0.05×10−3 mm2/s) as compared to both contralateral (FA=0.32±0.04, MD=1.0±0.05×10−3 mm2/s) and normal control (FA=0.32±0.04, MD=1.0±0.06×10−3 mm2/s) white matter. Significantly increased MD and decreased FA values were also observed in the polymicrogyric cortex (FA=0.08±0.01, MD=1.2±0.10×10−3 mm2/s) as compared to normal contralateral (FA=0.12±0.04, MD=1.1±0.09×10−3 mm2/s) and normal control (FA=0.12±0.01, MD=1.1±0.09×10−3 mm2/s) cortex.Conclusion Significantly decreased FA values with no change in MD values in the subcortical white matter subjacent to polymicrogyric cortex reflect microstructural changes in the white matter probably due to the presence of ectopic neurons. 相似文献
7.
Huisman TA Loenneker T Barta G Bellemann ME Hennig J Fischer JE Il'yasov KA 《European radiology》2006,16(8):1651-1658
The objectives were to study the “impact” of the magnetic field strength on diffusion tensor imaging (DTI) metrics and also to determine whether magnetic-field-related differences in T2-relaxation times of brain tissue influence DTI measurements. DTI was performed on 12 healthy volunteers at 1.5 and 3.0 Tesla (within 2 h) using identical DTI scan parameters. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were measured at multiple gray and white matter locations. ADC and FA values were compared and analyzed for statistically significant differences. In addition, DTI measurements were performed at different echo times (TE) for both field strengths. ADC values for gray and white matter were statistically significantly lower at 3.0 Tesla compared with 1.5 Tesla (% change between −1.94% and −9.79%). FA values were statistically significantly higher at 3.0 Tesla compared with 1.5 Tesla (% change between +4.04 and 11.15%). ADC and FA values are not significantly different for TE=91 ms and TE=125 ms. Thus, ADC and FA values vary with the used field strength. Comparative clinical studies using ADC or FA values should consequently compare ADC or FA results with normative ADC or FA values that have been determined for the field strength used.This paper was presented at the 21st Annual Scientific Meeting of the ESMRMB, September 9–12, 2004, Copenhagen, Denmark 相似文献
8.
Ozgur Cakir Arzu Arslan Nagihan Inan Yonca Anık Tahsin Sarısoy Sevtap Gumustas Gur Akansel 《European journal of radiology》2013
Purpose
To evaluate the diagnostic efficiency of the diffusion parameters measured by conventional diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) for discrimination of malignant breast lesions from benign lesions and the normal breast.Materials and methods
The study included 52 women with 55 breast lesions (30 malignant, 25 benign). DTI and DWI were performed complementary to dynamic contrast MRI at 3T. Apparent diffusion coefficient (ADC) of DWI, mean diffusivity (MD) and fractional anisotropy (FA) values of DTI were measured for lesions and contralateral breast parenchyma in each patient. We used b factors of 0, 50, 850, 1000 and 1500 s/mm2 for DWI and b 0 and 1000 s/mm2 for DTI. ADC, MD and FA values were compared between malignant and benign lesions, and the normal parenchyma by univariate and multivariate analyses.Results
Diffusion parameters showed no difference according to menopausal status in the normal breast. ADC and MD values of the malignant lesions were significantly lower than benign lesions and normal parenchyma (p = 0.001). The FA showed no statistical significance. With the cut-off values of ≤1.23 × 10−3 mm2/s (b 0–1000 s/mm2) and ≤1.12 × 10−3 mm2/s (b 0–1500 s/mm2), ADC showed 92.85% and 96.15% sensitivity; 72.22% and 73.52% PPV, respectively. With a cut-off value of ≤1.27 × 10−3 mm2/s (b 1000 s/mm2), MD was 100% sensitive with a PPV of 65.90%. Comparing the diagnostic performance of the parameters in DTI with DWI, we obtained similar efficiency of ADC with b values of 0,1000 and 0,1500 s/mm2 and MD with a b value of 0, 1000 s/mm2 (AUC = 0.82 ± 0.07).Conclusion
ADC of DWI and MD of DTI values provide significant discriminative factors for benign and malignant breast lesions. FA measurement was not discriminative. Supported with clinical and dynamic contrast MRI findings, DWI and DTI findings provide significant contribution to the final radiologic decision. 相似文献9.
Gürses B Kabakci N Kovanlikaya A Firat Z Bayram A Uluğ AM Uluo AM Kovanlikaya I 《European radiology》2008,18(4):716-721
The aim of this study was to assess the feasibility of diffusion tensor imaging (DTI) of the prostate and to determine normative
fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of healthy prostate with a 3-Tesla magnetic resonance
imaging (MRI) system. Thirty volunteers with a mean age of 28 (25–35) years were scanned with a 3-Tesla MRI (Intera Achieva;
Philips, The Netherlands) system using a six-channel phased array coil. Initially, T2-weighted turbo spin-echo (TSE) axial
images of the prostate were obtained. In two subjects, a millimetric hypointense signal change was detected in the peripheral
zones on T2-weighted TSE images. These two subjects were excluded from the study. DTI with single-shot echo-planar imaging
(ssEPI) was performed in the remaining 28 subjects. ADC and FA values were measured using the manufacturer supplied software
by positioning 9-pixel ROIs on each zone. Differences between parameters of the central and peripheral zones were assessed.
Mean ADC value of the central (1.220 ± 0.271 × 10−3 mm2/s) was found to be significantly lower when compared with the peripheral gland (1.610 ± 0.347 × 10−3 mm2/s) (P < 0.01). Mean FA of the central gland was significantly higher (0.26), compared with the peripheral gland (0.16) (P < 0.01). This study shows the feasibility of prostate DTI with a 3-Tesla MR system and the normative FA and ADC values of
peripheral and central zones of the normal prostate. The results are compatible with the microstructural organization of the
gland.
An erratum to this article can be found at 相似文献
10.
Introduction We sought to determine whether diffusion-tensor imaging (DTI) can detect in vivo axonal damage in the corticopontocerebellar
pathway of patients with adult-onset ataxic neurodegenerative disease.
Methods Conventional MRI and DTI were performed on 18 patients with adult-onset ataxic neurodegenerative disease and 28 age-matched
control subjects. Fractional anisotropy (FA) and the mean diffusivity (MD) were measured in the ventral, central, and dorsal
pons, middle cerebellar peduncle (MCP) and internal capsule to evaluate corticopontocerebellar projection. Changes in FA and
MD values were compared between patients and controls. Clinical disability was assessed according to the International Cooperative
Ataxia Rating Scale (ICARS). The relationship between DTI measurements and ICARS was studied. Follow-up MRI was performed
in five patients approximately 1 year later.
Results FA values were significantly lower in the ventral and central portions of the pons, MCP, and internal capsules than in these
areas in control subjects (P < 0.05) with the lower FA values correlating with poorer ICARS (r > −0.57, P < 0.05). MD values were elevated in these areas, but the differences were smaller than for the FA values. No relationship
was observed between the MD and ICARS. In the five patients who underwent the follow-up study, there were significant decreases
between the initial study and the follow-up DTI study for FA in the MCP and internal capsule (P < 0.05).
Conclusion DTI can demonstrate a degenerated corticopontocerebellar pathway in patients, and FA values can be correlated with ataxia
severity. DTI may be a clinically useful tool as a quantitative surrogate marker for monitoring disease progression. 相似文献
11.
Ulrike Löbel Jan Sedlacik Daniel Güllmar Werner A. Kaiser Jürgen R. Reichenbach Hans-Joachim Mentzel 《Neuroradiology》2009,51(4):253-263
Introduction The aim of our work was to investigate the process of myelination in healthy patients using the diffusion parameters apparent
diffusion coefficient (ADC), relative anisotropy (RA), fractional anisotropy (FA), and eigenvalues. Age-dependent changes
were assessed using the slope m of the fit functions that best described the data.
Materials and methods Seventy-two patients (3 weeks–19 years) without pathological magnetic resonance imaging findings were selected from all pediatric
patients scanned with diffusion tensor imaging over a 5-year period at our institution. ADC, RA, FA, and eigenvalue maps were
calculated and regions of interest were selected in anterior/posterior pons, genu/splenium of corpus callosum (CC), anterior/posterior
limb of internal capsule (IC), and white matter (WM) regions (frontal, temporal, parietal, occipital WM). Statistical analysis
was performed using Spearman correlation coefficient and regression analysis.
Results Mean values ranged 71.6 × 10−5 to 90.3 × 10−5 mm2/s (pons/parietal WM) for ADC, 0.32–0.94 (frontal WM/CC) for RA, and 0.36–0.81 (frontal WM/splenium) for FA. Logarithmic fit
functions best described the data. Strong age influences were observed for CC, pons, and parietal/frontal WM and changes were
significant for all three eigenvalues, most pronounced for perpendicular eigenvalues. Changes in RA and FA differed depending
on the structure anisotropy.
Conclusions Changes observed for ADC, RA, FA, and eigenvalues with age were consistent with previous findings. Changes detected for RA
and FA varied due to the different scaling of both parameters. We found that the use of the largely linear scaled RA adds
more valuable information for the assessment of age-dependent structural changes as compared to FA. Additionally, we report
normative values for the diffusion parameters studied. 相似文献
12.
Kiroğlu Y Calli C Yunten N Kitis O Kocaman A Karabulut N Isaev H Yagci B 《Neuroradiology》2006,48(12):875-880
Introduction The aim of this study was to evaluate the role of diffusion-weighted imaging (DWI) in the diagnosis of viral encephalitis and its relationship with the stage of the illness.Methods We performed conventional magnetic resonance imaging (MRI) including T1-W, T2-W and fluid attenuated inversion recovery (FLAIR) sequences and DWI in 18 patients with viral encephalitis diagnosed on the basis of laboratory, clinical and radiologic findings. Based on the qualitative and quantitative comparison of the conventional MRI and DWI, the patients were divided into three groups. Apparent diffusion coefficient (ADC) values of the involved and contralateral normal brain tissues were computed and compared for each group. The degree of correlation between the time (TI) from the onset of neurologic symptoms to the MR examination and ADC values was determined.Results In group I (n=11) DWI was superior to conventional MRI in detecting the encephalitic involved sites and in depicting the borders of the encephalitic lesions. In group II (n=4) DWI was similar to conventional MRI. In group III (n=3) conventional MRI was superior to DWI. Mean ADC values of affected versus contralateral normal brain tissues were 0.458±0.161×10−3 versus 0.86±0.08×10−3 in group I, 0.670±0.142×10−3 versus 0.93±0.07×10−3 in group II, and 1.413±0.211×10−3 versus 1.05±0.06×10−3 in group III. Patients in group I had significantly lower ADC values than those in group II, while patients in group III had the highest ADC values (P<0.05). The ADC values were significantly lower in the affected sites than in the unaffected sites of patients in groups I and II, but were significantly higher in the affected sites than in the unaffected sites of patients in group III (P<0.05). There was an excellent correlation between ADC values and duration of the disease (r=0.874, P=0.01).Conclusion DWI is superior to other conventional diagnostic MR sequences in the detection of early viral encephalitic lesions and depiction of the lesion borders and, in combination with other sequences, DWI may contribute to the determination of the disease phase. 相似文献
13.
Yoshikawa T Aoki S Abe O Hayashi N Masutani Y Masumoto T Mori H Satake Y Ohtomo K 《Radiation Medicine》2008,26(8):481-487
Purpose The aim of the study was to estimate the effect of distortion correction with correspondence to numbers of encoding directions
to acquire diffusion tensor imaging (DTI) of improved quality.
Materials and methods Ten volunteers underwent DTI of the head using echo planar imaging with 6, 13, 27, and 55 encoding directions. Fractional
anisotropy (FA) maps and apparent diffusion coefficient (ADC) maps were created before and after distortion correction. Regions
of interest were placed in the corpus callosum on each map, and standard deviations of FA and ADC were calculated. FA maps
were also evaluated visually by experienced neuroradiologists.
Results Dispersion of standard deviations tended to be reduced after distortion correction, with significant differences found in
FA maps with 6 encoding directions, ADC maps with 6 directions, and ADC maps with 13 directions (P < 0.001, P < 0.005, and P < 0.05, respectively). Visual image quality was improved after distortion correction (P < 0.01 for all of the visual comparisons).
Conclusion Distortion correction is effective in providing DTI of enhanced quality, notwithstanding the number of encoding directions.
This article was presented at a Japan Radiological Society meeting in 2002 相似文献
14.
Introduction We prospectively compared the fractional anisotropy (FA) and mean diffusivity (MD) of the peritumoral edema of meningiomas
and metastatic brain tumors with diffusion-tensor magnetic resonance (MR) imaging.
Methods The study protocol was approved by the local ethics committee, and written informed consent was obtained. Preoperative diffusion-tensor
MR imaging was performed in 15 patients with meningiomas and 11 patients with metastatic brain tumors. Regions of interest
(ROI) were placed in the peritumoral edema and normal-appearing white matter (NAWM) of the contralateral hemisphere to measure
the FA and MD. The FA and MD ratios were calculated for each ROI in relation to the NAWM of the contralateral hemisphere.
Changes in peritumoral MD and FA, in terms of primary values and ratios, were compared using a two-sample t-test; P < 0.05 was taken as indicating statistical significance.
Results The mean MD values (×10−3 mm2/s) of the peritumoral edema for metastases and meningiomas, respectively, were 0.902 ± 0.057 and 0.820 ± 0.094, the mean
MD ratios were 220.3 ± 22.6 and 193.1 ± 23.4, the mean FA values were 0.146 ± 0.026 and 0.199 ± 0.052, and the mean FA ratios
were 32.3 ± 5.9 and 46.0 ± 12.1. All the values were significantly different between metastases and meningiomas (MD values
P = 0.016, MD ratios P = 0.006, FA values P = 0.005, FA ratios P = 0.002).
Conclusion The peritumoral edema of metastatic brain tumors and meningiomas show different MD and FA on diffusion-tensor MR imaging. 相似文献
15.
Pasco A Ter Minassian A Chapon C Lemaire L Franconi F Darabi D Caron C Benoit JP Le Jeune JJ 《European radiology》2006,16(7):1501-1508
The distinction between intracellular (ICE) and extracellular edema (ECE) has a crucial prognostic and therapeutic importance
in patients with severe traumatic brain injury (STBI). Indeed, ICE usually leads to cellular death, and maintenance of a cerebral
perfusion pressure (CPP) above 70 mmHg is still under debate since this practice may increase ECE. The purpose of this study
was to describe the ECE and ICE kinetics associated with STBI using quantitative diffusion MRI. Twelve patients were prospectively
studied. The initial ADC in ICE measured on day 1.3±0.7 is significantly reduced compared to normal-appearing parenchyma (0.51±0.12
* 10−3 mm2/s vs. 0.76±0.03 * 10−3 mm2/s, n=12, P<0.0001) and reaches normality on MRI 3 performed on day 14.2±3.3. In patients presenting an extension of ICE on MRI 2 performed
on day 6.7±1.4 (ADCMRI2=0.40±0.11 * 10−3 mm2/s), ADC values in the extension area at the first MRI were slightly, but not significantly reduced compared to normal parenchyma
(0.69±0.05 * 10-3 mm2/s, P=0.29). Normalization occurred equally by day 14. ADC in ECE (1.34±0.22 * 10−3 mm2/s) was elevated and stable with time under CPP therapy. Therefore, ECE is not worsened by CCP therapy, and ICE appears more
relevant than ECE in STBI. 相似文献
16.
Introduction We describe the magnetic resonance (MR) imaging characteristics of dysembryoplastic neuroepithelial tumors (DNT) and discuss
their differential diagnosis.
Material and methods Proton MR spectroscopy (TE 30 and 136 ms), diffusion-weighted and perfusion images were retrospectively evaluated in 22 patients
with pathologically proven DNT (17 male and 5 female, mean age 18.7 years) and 14 control subjects (10 male and 4 female,
mean age 16.9 years). The results from the DNT patients and from the control subjects were compared using an independent sample
t-test and the degree of correlation was tested by Pearson’s correlation.
Results All DNTs were solitary and in a supratentorial cortical or subcortical location (ten temporal, eight frontal and four parietal).
They had low-signal on T1-weighted images and high-signal on T2-weighted images without a prominent mass effect. Additionally
a cystic appearance (six patients, 27.3%), cortical dysplasia (six patients, 27.3%) and contrast enhancement (four patients,
18.2%) were also noted. No significant differences were detected in NAA/Cho, NAA/Cr, NAA/Cho+Cr or Cho/Cr ratios between DNT
and normal brain. DNTs had a significantly higher mI/Cr ratio and apparent diffusion coefficient (ADC) values and lower cerebral
blood values than normal parenchyma (P < 0.001). ADC had the highest correlation with the diagnosis of DNT (r = 0.996) followed by relative cerebral blood volume (rCBV) (r = −0.883) and mI/Cr ratio (r = 0.663).
Conclusion Proton MR spectroscopy, diffusion-weighted and perfusion imaging characteristics of DNTs provide additional information to
their MR imaging findings. The MR spectrum showing a slight increase in mI/Cr ratio, and higher ADC and lower rCBV values
than normal parenchyma help to differentiate DNTs from other cortical tumors, which had higher rCBV and lower ADC values than
DNTs.
This work was presented at the ASNR 45th Annual Meeting 2007. 相似文献
17.
PurposeTo evaluate whether diffusion tensor imaging (DTI) can be used to differentiate malignant parotid gland tumors from the benign ones.Materials and methodsThe study population comprised 59 parotid gland tumors (24 Warthin’s tumors, 19 pleomorphic adenomas, seven other benign tumors, and nine malignant tumors). Single-shot echo-planar DTI was performed with motion-probing gradients along 30 noncollinear directions (b = 1000 s/mm2) at 3.0 T. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values for benign and malignant tumors were compared using the Mann–Whitney U test. Receiver-operating characteristic (ROC) curve analysis was performed to assess the ability of the ADC and FA values to differentiate malignant tumors from the benign ones.ResultsADC values showed no significant difference between malignant (0.93 ± 0.21 × 10−3 mm2/s) and benign tumors (1.19 ± 0.50 × 10−3 mm2/s) (p = 0.225). FA values of malignant tumors were significantly higher than those of benign tumors (0.26 ± 0.06 vs. 0.17 ± 0.05, p < 0.001). The area under the ROC curve of FA was significantly greater than that under the curve of ADC (0.884 vs. 0.628, p = 0.010).ConclusionsDTI, particularly FA, can help differentiate malignant parotid gland tumors from the benign ones. 相似文献
18.
19.
Fujii S Matsusue E Kigawa J Sato S Kanasaki Y Nakanishi J Sugihara S Kaminou T Terakawa N Ogawa T 《European radiology》2008,18(2):384-389
Our purpose is to evaluate the diagnostic accuracy of apparent diffusion coefficient (ADC) measurement in differentiating
malignant from benign uterine endometrial cavity lesions. We retrospectively evaluated 25 uterine endometrial cavity lesions
in 25 female patients: endometrial carcinoma (n = 11), carcinosarcoma (n = 2), submucosal leiomyoma (n = 8), and endometrial
polyp (n = 4). Diffusion-weighted images were performed at 1.5 T with b factors of 0–1,000/mm2. The region of interest was defined within the tumor on T2-weighted EPI image and then manually copied to an ADC map. Thereby,
the ADC value was obtained. We compared ADC values between malignant and benign lesions using Student’s t-test. The mean and
standard deviation of ADC values (×10−3 mm2/s) were as follows: endometrial carcinoma, 0.98±0.21; carcinosarcoma, 0.97±0.02; submucosal leiomyoma, 1.37±0.28; and endometrial
polyp, 1.58±0.45. The ADC values differed significantly between malignant (0.98±0.19) and benign lesions (1.44±0.34) (P < 0.01).
We defined malignant tumors as cases with an ADC value less than 1.15 × 10−3 mm2/s for obtaining the highest accuracy. Sensitivity, specificity, and accuracy were 84.6%, 100%, and 92%, respectively. ADC
measurement can provide useful information in differentiating malignant from benign uterine endometrial cavity lesions. 相似文献
20.
Roman Guggenberger Daniel Nanz Lorenz Bussmann Avneesh Chhabra Michael A. Fischer Jürg Hodler Christian W.A. Pfirrmann Gustav Andreisek 《European journal of radiology》2013