共查询到20条相似文献,搜索用时 46 毫秒
1.
Holzapfel K Duetsch S Fauser C Eiber M Rummeny EJ Gaa J 《European journal of radiology》2009,72(3):381-387
Purpose
To evaluate echo-planar diffusion-weighted MR imaging (DWI) in the differentiation between benign and malignant cervical lymph nodes.Materials and methods
35 consecutive patients with 55 enlarged (>10 mm) cervical lymph nodes underwent MR imaging at 1.5-T. DWI was performed using a single-shot echo-planar (SSEPI) MR imaging sequence with b values (b: diffusion factor) of 0, 500 and 1000 s/mm2. Apparent diffusion coefficient (ADC) maps were reconstructed for all patients and ADC values were calculated for each lymph node. Imaging results were correlated with histopathologic findings after neck dissection or surgical biopsy, findings in PET/CT or imaging follow-up. Mann-Whitney test was used for statistical analysis and a receiver operating characteristic (ROC) curve analysis was performed.Results
Cervical lymph node enlargement was secondary to metastases from squamous cell carcinomas [n = 25], non-Hodgkin’s lymphoma [n = 6], reactive lymphadenitis [n = 20], cat scratch lymphadenitis [n = 2] and sarcoidosis [n = 2]. The mean ADC values (×10−3 mm2/s) were 0.78 ± 0.09 for metastatic lymph nodes, 0.64 ± 0.09 for lymphomatous nodes and 1.24 ± 0.16 for benign cervical lymph nodes. ADC values of malignant lymph nodes were significantly lower than ADC values of benign lymph nodes. 94.3% of lesions were correctly classified as benign or malignant using a threshold ADC value of 1.02 × 10−3 mm2/s.Conclusion
According to our first experience, DWI using a SSEPI sequence allows reliable differentiation between benign and malignant cervical lymph nodes. 相似文献2.
The utility of diffusion-weighted MR imaging in differentiation of uterine adenomyosis and leiomyoma
Purpose
To investigate the value of diffusion-weighted MR imaging (DWI), especially apparent diffusion coefficient (ADC) in the differentiation of uterine adenomyosis and leiomyoma.Materials and methods
17 patients with uterine leiomyoma and 22 patients with uterine adenomyosis underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values, as well as ADC D-value (defined as the ADC value of high signal intensive foci minus the ADC value of lesion tissues the difference in value), were measured and compared to investigate whether they could help in the differentiation of uterine adenomyosis and leiomyoma. Histopathologic examination was conducted as the golden standard.Results
For high signal intensive foci within the lesions, uterine adenomyosis demonstrated significantly lower mean ADC value than uterine leiomyoma (1.582 vs. 2.122 × 10−3 mm2/s, P = 0.001). For lesion tissues, uterine adenomyosis demonstrated significantly higher mean ADC value than uterine leiomyoma (1.214 vs. 0.967 × 10−3 mm2/s, P = 0.001). However, there was overlap between uterine adenomyosis and leiomyoma in both measurements. Mean ADC D-value was significantly lower in uterine adenomyosis than in uterine leiomyoma (0.369 vs. 1.096 × 10−3 mm2/s, P = 0.000). ADC D-value had no overlap between uterine adenomyosis and leiomyoma.Conclusion
DWI can be applied for the further differentiation of uterine adenomyosis and leiomyoma, in addition to routine MR imaging. ADC D-value may be a more useful tool than ADC value in the differentiation. 相似文献3.
Purpose
To investigate the value of diffusion-weighted MR imaging (DWI) in detection of cervical cancer, and to determine the diagnostic accuracy of apparent diffusion coefficient (ADC) values for evaluating cervical cancer before and after chemoradiotherapy.Materials and methods
Thirty-three patients with cervical squamous carcinoma and 20 patients with other pelvic abnormalities underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging. The ADC values of normal cervical tissue, cervical area before and after chemoradiotherapy were measured and compared. Receiver operating characteristic (ROC) analysis was employed to investigate whether ADC values could help in discrimination among normal cervical tissue, cervical cancer before and after therapy, and to obtain the optimal ADC threshold value.Results
Cervical cancer lesion demonstrated obviously hyperintensity on DWI images. The mean ADC value of cervical carcinoma (1.110 ± 0.175 × 10−3 mm2/s) was significantly lower than that of normal cervical tissue (1.593 ± 0.151 × 10−3 mm2/s) (P < 0.001). The mean ADC value of the cervical area in 22 patients treated by chemoradiotherapy (1.436 ± 0.129 × 10−3 mm2/s) was significantly higher than that before therapy (1.013 ± 0.094 × 10−3 mm2/s) (P < 0.001). The difference of ADC values between normal cervical tissue and cervical area after therapy was statistically significant (P < 0.01). The optimal ADC threshold values for distinguishing between normal cervical tissue and cervical carcinoma was 1.359 × 10−3 mm2/s, between cervical area before and after therapy was 1.255 × 10−3 mm2/s, between normal cervical tissue and cervical area after therapy was 1.525 × 10−3 mm2/s. The sensitivity and specificity were 100% and 84.8%, 95.5% and 100%, 70% and 81.8%, respectively.Conclusion
DWI can be applied for the detection of cervical cancer because of its superior disease contrast with normal tissue. The measurement of the ADC values can be a useful tool to monitor the response to therapy for cervical carcinoma. 相似文献4.
Hazem M. El Shahat Hadeer S. FahmyGhada K. Gouhar 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Purpose
The aim of this study was to determine the role of diffusion-weighted MR imaging (DWI) and the apparent diffusion coefficient (ADC) in characterization of head and neck lesions.Patients and methods
MR imaging including diffusion-weighted sequences was performed on 43 patients presented with head and neck lesions. Images were obtained with a diffusion-weighted factor (b factor) of 100, 500, and 1000 s/mm2. ADC maps were reconstructed, and the ADC value of the lesions was calculated.Results
The mean ADC value of malignant tumors was (1.02 ± 0.22) × 10−3 mm2/s (n = 31). The mean ADC value of benign tumors was (1.62 ± 0.27) × 10−3 mm2/s (n = 12). The mean ADC of lymphomas was significantly lower than that of carcinomas. The difference in the ADC value between the malignant tumors and benign lesions was statistically significant (p < 0.001). Selection of (1.2) × 10−3 mm2/s as a threshold value of ADC for differentiating benign from malignant tumors yielded the best result, with an accuracy of 94%, sensitivity of 95%, specificity of 92%, positive predictive value of 92% and negative predictive value of 94%.Conclusion
DWI and the ADC measurement are promising, non-invasive imaging approach that can be used for characterization of head and neck lesions. It can help differentiate malignant tumors from benign lesions. 相似文献5.
Ahmed Abdel Khalek Abdel Razek Ahmed AbdallaEman Omran Abeer FathyKhaled Zalata 《European journal of radiology》2011,78(1):129-134
Purpose
To evaluate the accuracy of diffusion weighted MR imaging in diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis.Materials and methods
Sixty-three consecutive children (40 boys, 23 girls, median age 9.3 years), with chronic hepatitis and thirty age matched volunteers underwent diffusion weighted MR imaging of the liver using a single shot echoplanar imaging with b-value = 0, 250, and 500 s/mm2. Liver biopsy was obtained with calculation of METAVIR score. The ADC value of the liver was correlated with METAVIR score. Receiver operating characteristic curve was done for diagnosis and grading of hepatic fibrosis.Results
There was statistical difference in the mean ADC value between volunteers and patients with hepatic fibrosis (P = 0.001) and in patients with different grades of METAVIR scores (P = 0.002). There was correlation between the mean ADC value and METAVIR score (r = 0.807, P = 0.001). The cut off point to predict fibrosis (1.7 × 10−3 mm2/s) revealed 83% accuracy, 85% sensitivity, 82% specificity, 83% PPV, and 85% NPV. The area under the curve was 0.91 for F1, 0.85 for F2, 0.86 for F3 and 0.90 for F4.Conclusion
The apparent diffusion coefficient value is a promising quantitative parameter used for diagnosis and quantification of hepatic fibrosis in children with chronic hepatitis. 相似文献6.
Faten Fawzy Mohammad Doaa Ibrahim Hasan Mohamed Gouda Ammar 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Background
MR spectroscopy and diffusion-weighted imaging are useful non invasive imaging modalities used for characterization of different sellar and suprasellar lesions.Patient and methods
We studied 30 cases of suprasellar SOLs (as proved by conventional MRI), MRS and DWI. Our findings were correlated with histopathological analysis after surgical resection.Results
Three false positive cases in which cMRI give diagnosis mismatched with that obtained after adding the MRS findings and ADC values. MR spectrum type IIC is found in macroadenoma, craniopharyngioma, meningioma and germinoma with characteristic broad lipid peak in the second and forth types and elevated alanine peak in meningioma. Glioma had MRS appearance of type IIB. Simple differentiation between tumor types were achieved by the mean ADC values which were statistically significant (p < 0.001) when correlated to the histological diagnosis. When the ADC value of 0.6 × 10−3 mm2/s this strongly points to macroadenoma, ADC value of 1.05 × 10−3 mm2/s in meningiomas, ADC value 1.88 8 × 10−3 mm2/s strongly points to craniopharyngioma, while gliomas and germinoma had ADC values 1.6 × 10−3 mm2/s and 1.0 × 10−3 mm2/s respectively.Conclusion
MR spectroscopy and DWMRI are considered important diagnostic tools complementary to cMRI in pre-surgical evaluation and discrimination between different sellar and suprasellar lesions. 相似文献7.
Nickolas Papanikolaou Spyros Yarmenitis Nicholas Gourtsoyiannis 《European journal of radiology》2010,73(2):305-309
Purpose
To compare two quantification techniques of apparent diffusion coefficient (ADC), both in normal liver parenchyma and focal lesions, and to investigate any potential value of normalization.Materials and methods
Fifty-six consecutive patients underwent MRI examination of the liver, including a single shot spin-echo echo planar imaging diffusion sequence with four b-values (0, 50, 500 and 1000 s/mm2). ADC maps were reconstructed based on a two-point method (b-values: 500 and 1000 s/mm2) and a four-point method (b-values: 0, 50, 500 and 1000 s/mm2). Comparison of absolute ADC measurements of the liver, benign and malignant focal lesions was performed between the two- and four-point techniques. The same analysis was done on normalized ADC values (absolute ADC values divided by spleen ADC values).Results
The difference between mean two-point and four-point ADC values of normal liver (absolute: 1.237 × 10−3, 1.615 × 10−3 mm2/s, normalized: 1.40, 1.52, respectively) was statistically significant (p < 0.0001 and p = 0.0061). Significantly higher absolute ADC values of benign and malignant lesions were recorded with the four-point method (2.860 × 10−3 and 1.307 × 10−3 mm2/s) over the two-point method (2.243 × 10−3, and 1.011 × 10−3 mm2/s) (p < 0.0001 in both) while the same differences in normalized values were proven statistically non-significant for benign lesions (p = 0.788) and statistically significant for malignant lesions (p = 0.015). Both differences in absolute and normalized ADC values of benign versus malignant lesions based on two- and four-point methods were found to be significant (p < 0.0001).Conclusion
ADC quantification of the liver may be performed with a two-point method (b-values of 500 and 1000 s/mm2), while normalization of ADC measurements with the spleen is not further improving lesion characterization. 相似文献8.
Baris Bakir Artur Salmaslio?lu Arzu Poyanl? Izzet Rozanes Bulent Acunas 《European journal of radiology》2010,74(1):214-220
Purpose
The aim of our study is to demonstrate the feasibility of body diffusion weighted (DW) MR imaging in the evaluation of pancreatic islet cell tumors (ICTs) and to define apparent diffusion coefficient (ADC) values for these tumors.Materials and methods
12 normal volunteers and 12 patients with histopathologically proven pancreatic ICT by surgery were included in the study. DW MR images were obtained by a body-phased array coil using a multisection single-shot echo planar sequence on the axial plane without breath holding. In addition, the routine abdominal imaging protocol for pancreas was applied in the patient group. We measured the ADC value within the normal pancreas in control group, pancreatic ICT, and surrounding pancreas parenchyma. Mann-Whitney U-test has been used to compare ADC values between tumoral tissues and normal pancreatic tissues of the volunteers. Wilcoxon Signed Ranks Test was preferred to compare ADC values between tumoral tissues and surrounding pancreatic parenchyma of the patients.Results
In 11 patients out of 12, conventional MR sequences were able to demonstrate ICTs succesfully. In 1 patient an indistinct suspicious lesion was noted at the pancreatic tail. DW sequence was able to demonstrate the lesions in all of the 12 patients. On the DW images, all ICTs demonstrated high signal intensity relative to the surrounding pancreatic parenchyma. The mean and standard deviations of the ADC values (×10−3 mm2/s) were as follows: ICT (n = 12), 1.51 ± 0.35 (0.91-2.11), surrounding parenchyma (n = 11) 0.76 ± 0.15 (0.51-1.01) and normal pancreas in normal volunteers (n = 12), 0.80 ± 0.06 (0.72-0.90). ADC values of the ICT were significantly higher compared with those of surrounding parenchyma (p < 0.01) and normal pancreas (p < 0.001).Conclusion
DW MR imaging does not appear to provide significant contribution to routine MR imaging protocol in the evaluation of pancreatic islet cell tumors. But it can be added to MR imaging protocol to detect the lesion in a limited number of patients with clinical suspicion for pancreatic ICT with negative or suspicious imaging findings. 相似文献9.
Adel El-Badrawy Maha Elzaafarany Tamer F. Youssef Mohammed Kh. El-Badrawy 《The Egyptian Journal of Radiology and Nuclear Medicine》2011,42(2):147-151
Purpose
To determine the role of diffusion weighted MR imaging and apparent diffusion coefficient (ADC) in chest wall masses.Materials and methods
This study included 62 patients with chest wall masses. They underwent routine MR imaging and diffusion MR weighted imaging on a 1.5 T MR unit (Symphony-Siemens). Diffusion MR imaging was done with diffusion factor b value of 0, 500, and 1000 s/mm2. The apparent diffusion coefficient (ADC) map was reconstructed. The signal intensity was visually assessed on ADC maps and ADC value was measured in chest wall lesions. The mean ADC values correlated with histo-pathological results.Results
Adequate ADC maps were obtained in 62 patients. The mean ADC values of chest wall lesions were 1.76 ± 0.08 × 10−3 mm2/s in inflammatory lesion, 3.21 ± 0.05 × 10−3 mm2/s in the cystic lesions, 1.67 ± 0.03 × 10−3 mm2/s in neurofibroma, 2.12 ± 0.07 × 10−3 in haemangioma, and 0.89 ± 0.06 × 10−3 mm2/s in malignant tumors. The mean ADC value of the malignant tumor was significantly different from that of benign chest wall tumors (P < 0.001).Conclusion
Diffusion weighted MR imaging is a new imaging modality for differentiation malignant from benign chest wall masses. In addition, it has a role in characterization of different malignant and benign tumors. 相似文献10.
Nina Gahr Kassa Darge Gabriele HahnBjörn W. Kreher Miriam von BuirenMarkus Uhl 《European journal of radiology》2011,79(3):443-446
Purpose
The purpose of this study was to assess the apparent diffusion coefficient (ADC) of neuroblastic tumours and to evaluate if the ADC can enable differentiation of neuroblastoma and ganglioneuroma/ganglioneuroblastoma.Patients and methods
16 histologically classified tumours (10 neuroblastomas and 6 ganglioneuroma/ganglioneuroblastoma) were investigated in 15 children. Diffusion-weighted echo-planar imaging was performed with a b-value of 800 s/mm2. The contrast of tumour tissue depicted with T2-weighted images and diffusion-weighted images was evaluated by means of region-of-interest (ROI) measurements and a calculation of the ADC by a software tool. The ADC of the psoas-muscle was measured to establish an internal standard, too.Results
The mean ADC of the 10 neuroblastomas was 0.81 × 10−3 mm2/s (SD 0.29 × 10−3 mm2/s, range 0.39-1.47 × 10−3 mm2/s). The mean ADC of the four ganglioneuroma and two ganglioneuroblastoma was 1.6 × 10−3 mm2/s (SD 0.340 × 10−3 mm2/s, range 1.13-1.99) × 10−3 mm2/s. The difference was significant in the t-test (p = 0.01). We found no ganglioneuroma or ganglioneuroblastoma with an ADC below 1.1 × 10−3 mm2/s.Discussion
There is a significant difference of the ADC of neuroblastoma compared to the ADC of ganglioneuroma/ganglioneuroblastoma. These first results suggest that the diffusion-weighted imaging could differentiate neuroblastoma and ganglioneuroma/ganglioneuroblastoma by calculating the ADC. 相似文献11.
Roman Guggenberger Daniel Nanz Lorenz Bussmann Avneesh Chhabra Michael A. Fischer Jürg Hodler Christian W.A. Pfirrmann Gustav Andreisek 《European journal of radiology》2013
Objective
To assess the agreement of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the median nerve on 3.0 T MR scanners from different vendors.Materials and methods
IRB approved study including 16 healthy volunteers (9 women; mean age 30.6 ± 5.3 years). Diffusion tensor imaging (DTI) of the dominant wrist was performed on three 3.0 T MR scanners (GE, Siemens, Philips) using similar imaging protocols and vendor-proprietary hard- and software. Intra-, inter-reader and inter-vendor agreements were assessed.Results
ICCs for intra-/inter-reader agreements ranged from 0.843–0.970/0.846–0.956 for FA, and 0.840–0.940/0.726–0.929 for ADC, respectively.ANOVA analysis identified significant differences for FA/ADC measurements among vendors (p < 0.001/p < 0.01, respectively). Overall mean values for FA were 0.63 (SD ± 0.1) and 0.999 × 10−3 mm2/s (SD ± 0.134 × 10−3) for ADC. A significant negative measurement bias was found for FA values from the GE scanner (−0.05 and −0.07) and for ADC values from the Siemens scanner (−0.053 and −0.063 × 10−3 mm2/s) as compared to the remainder vendorsConclusion
FA and ADC values of the median nerve obtained on different 3.0 T MR scanners differ significantly, but are in comparison to the standard deviation of absolute values small enough to not have an impact on larger group studies or when substantial diffusion changes can be expected. However, caution is warranted in an individual patient when interpreting diffusion values from different scanner acquisitions 相似文献12.
Hidetake Yabuuchi Yoshio Matsuo Taro Setoguchi Hiroyasu Soeda Masamitsu Hatakenaka Eriko Tokunaga Hiroshi Honda 《European journal of radiology》2010,75(1):e126
Purpose
To evaluate the diagnostic accuracy of a combination of dynamic contrast-enhanced MR imaging (DCE-MRI) and diffusion-weighted MR imaging (DWI) in characterization of lesions showing non-mass-like enhancement on breast MR imaging and to find the strongest discriminators between carcinoma and benignancy.Materials and methods
We analyzed consecutive MR images in 45 lesions showing non-mass like enhancement in 41 patients. We analyzed lesion size, distribution, internal enhancement, kinetic curve pattern, and apparent diffusion coefficient (ADC) values. We applied univariate and multivariate analyses to find the strongest indicators for malignancy. In a validation study, 22 non-mass-like enhancement lesions in 21 patients were examined. We calculated diagnostic accuracy when we presume category 4b, 4c, and 5 lesions as malignant or high to moderate suspicion for malignancy, and category 4a and 3 as low suspicion for malignancy or benign.Results
Segmental distribution (P = 0.018), clumped internal enhancement (P = 0.005), and ADC less than 1.3 × 10−3 mm2/s (P = 0.047) were the strongest MR indicators of malignancy. In a validation study, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 87% (13/15), 86% (6/7), 93% (13/14), 75% (6/8) and 86% (19/22), respectively.Conclusion
The combination of DCE-MRI and DWI showed high diagnostic accuracy in characterization of non-mass-like enhancement lesions on breast MR images. 相似文献13.
Mahmoud Abdel Latif Galal El HawaryAdel El Badrawy Hatem El Alfy 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Aim
To determine if focal liver masses could be differentiated as benign or malignant by DWI and ADC maps.Methods and materials
Sixty focal liver lesions were scanned using 1.5 T MRI. DWI was performed with b 0, b 500 and b 1000 gradients with ADC measurements. Comparison of mean ADC values between each benign and malignant lesion was done. Reference standard of diagnosis was obtained by correlating DWI with histopathologic findings and imaging follow-up. The accuracies of DWI and ADC values were assessed with the Student’s t test, and cut-off values were determined with receiver operating characteristic curve analysis.Results
When ADC value of 1.0 × 10−3 mm2/s was used as a threshold value for differentiation of malignant tumors from benign lesions, sensitivity was 90.3%, specificity 78.57% and accuracy 86.7%. The best result was obtained with the use of ADC cut off value (at b 500) of 1.5 × 10−3 mm2/s and ADC cut off value (at b 1000) of 1.0 × 10−3 mm2/s, with 90.3% sensitivity, 92.86% specificity, 91.1% accuracy, 96.6% positive predictive value and 81.3% negative predictive value.Conclusion
DWI and ADC map is a useful tool in differential diagnosis of malignant from benign liver lesions. 相似文献14.
Ali Koçyiğit Recep Bayram Selçuk Yüksel İsmail Yılmaz Nevzat Karabulut 《European journal of radiology》2014
Purpose
The apparent diffusion coefficient (ADC) which obtain from diffusion-weighted magnetic resonance imaging (DWI), is a quantitative parameter representing the renal function and parenchymal damage in some renal disorders. The primary aim of this study was to investigate whether renal tissue alterations associated with vesicoureteral reflux (VUR) can be displayed by DWI. The secondary aim was to assess how ADC values change with age in kidneys with and without VUR.Materials and methods
This prospective study included 46 patients (8 boys, 38 girls; mean age 7.3 ± 4.2; range 1–15 years) with VUR and 54 control subjects (21 boys, 33 girls; mean age 7.7 ± 5.2; range 1–17 years). All subjects underwent DWI of the kidneys using b value of 600 s/mm2 in addition to MR urography. The ADC values of 71 kidneys with VUR were compared with those of 81 kidneys without VUR.Results
The mean ADC values were (1.93 ± 0.36) × 10−3 mm2/s, (1.97 ± 0.24) × 10−3 mm2/s, (1.83 ± 0.37) × 10−3 mm2/s, (1.98 ± 0.20) × 10−3 mm2/s and (2.08 ± 0.42) × 10−3 mm2/s in normal kidneys, and in those with grade 1, grade 2, grade 3 and grade 4 VUR, respectively. There was no significant difference in ADC values between kidneys with and without VUR. There was a significant positive correlation between the age and ADC values both in kidneys with and without VUR (r = 0.79, p < 0.001 and r = 0.82; p < 0.001, respectively).Conclusion
DWI does not reveal probable parenchymal alterations in reflux nephropathy. ADC values increase with age during childhood not only in normal kidneys but also in kidneys with VUR. 相似文献15.
Zheng Yuan Xiao-Dan Ye Sheng Dong Li-Chao Xu Shi-Yuan Liu 《European journal of radiology》2010,75(1):e9
Objective
To investigate the value of hepatocellular carcinoma pretreatment apparent diffusion coefficients (ADCs) and its ADCs changes after treatment in predicting and early monitoring the response after chemoembolization.Materials and methods
Twenty-five responding and nine nonresponding hepatocellular carcinoma lesions were prospectively evaluated with magnetic resonance diffusion-weighted imaging in 24 h before and in 48 h after chemoembolization. Quantitative ADC maps were calculated with images with b values of 0 and 500 s/mm2.Results
Nonresponding lesions had a significantly higher pretreatment mean ADC than did responding lesions (1.726 ± 0.323 × 10−3 mm2/s vs.1.294 ± 0.185 10−3 mm2/s, P ≤ 0.001). The results of receiver operator characteristic (ROC) analysis for identification of nonresponding lesions showed that threshold ADC value of 1.618 × 10−3 mm2/s had 96.0% sensitivity and 77.8% specificity. After transarterial chemoembolization, responding lesions had a significant increase in %ADC values than did nonresponding lesions (32.63% vs. 5.24%, P = 0.025). The results of ROC analysis for identification of responding lesions showed that threshold %ADC value of 16.21% had 72% sensitivity and 100% specificity. No significant change was observed in normal liver parenchyma (P = 0.862) and spleen (P = 0.052).Conclusion
High pretreatment mean ADC value of hepatocellular carcinoma was predictive of poor response to chemoembolization. A significant increase in %ADC value was observed in lesions that responded to chemoembolization. 相似文献16.
Diffusion-weighted MRI in cervical lymph nodes: Differentiation between benign and malignant lesions
Anna PerronePietro Guerrisi Luciano IzzoIlaria D’Angeli Simona SassiLuigi Lo Mele Marina MariniDario Mazza Mario Marini 《European journal of radiology》2011,77(2):281-286
Objective
Purpose of our study was to assess the potential role of diffusion-weighted imaging (DWI) in the differential diagnosis between benign and malignant nodes.Subject and methods
We enrolled 32 subjects: 14 with benign lymphadenopathy, 17 patients with histologically proved malignant disease before beginning treatment and 1 patient with lymphoma after chemotherapeutic treatment.In all patients we used fast spin echo T2-weighted images in axial and coronal planes, fast spin echo T1-weighted images before and after contrast medium of administration in axial and coronal planes.Before contrast administration diffusion sequences were acquired on the axial and coronal plane (b factor of 0.500 and 1000 s/mm2) and then apparent diffusion coefficient (ADC) maps were reconstructed.Results
On diffusion images, 13/14 patients with benign nodes showed low signal intensity and had high signal on ADC maps, whereas all patients with malignant diseases appeared hyperintense on diffusion images and with low signal intensity on ADC maps. Only a patient with tuberculosis showed a low ADC value. The mean ADC value of malignant nodes was about 0.85 × 10−3 mm2/s, the mean value of benign nodes was 1.448 × 10−3 mm2/s; this difference was statistically significant (p < 0.01). The mean ADC value of treated nodes was 1.75 × 10−3 mm2/s. The best threshold value was 1.03 × 10−3 mm2/s, obtaining a sensitivity of 100% and a specificity of 92.9%.Conclusions
Diffusion imaging could be considered an important supportive tool for the diagnosis of enlarged cervical lymphadenopathies. 相似文献17.
Claus Koelblinger Julia Fruehwald-Pallamar Klaus Kubin Mirja Wallner-Blazek Luc van den Hauwe Leonardo Macedo Stefan B. Puchner Majda M. Thurnher 《European journal of radiology》2013
Introduction
The purpose of this study was to evaluate MR imaging characteristics with conventional and advanced MR imaging techniques in patients with IIDL.Methods
MR images of the brain in 42 patients (20 male, 22 female) with suspected or known multiple sclerosis (MS) from four institutions were retrospectively analyzed. Lesions were classified into five different subtypes: (1) ring-like lesions; (2) Balo-like lesions; (3) diffuse infiltrating lesions; (4) megacystic lesions; and (5) unclassified lesions.The location, size, margins, and signal intensities on T1WI, T2WI, and diffusion-weighted images (DWI), and the ADC values/ratios for all lesions, as well as the contrast enhancement pattern, and the presence of edema, were recorded.Results
There were 30 ring-like, 10 Balo-like, 3 megacystic-like and 16 diffuse infiltrating-like lesions were detected. Three lesions were categorized as unclassified lesions.Of the 30 ring-like lesions, 23 were hypointense centrally with a hyperintense rim. The mean ADC, measured centrally, was 1.50 ± 0.41 × 10−3 mm2/s. The mean ADC in the non-enhancing layers of the Balo-like lesions was 2.29 ± 0.17 × 10−3 mm2/s, and the mean ADC in enhancing layers was 1.03 ± 0.30 × 10−3 mm2/s. Megacystic lesions had a mean ADC of 2.14 ± 0.26 × 10−3 mm2/s. Peripheral strong enhancement with high signal on DWI was present in all diffuse infiltrating lesions. Unclassified lesions showed a mean ADC of 1.43 ± 0.13 mm2/s.Conclusion
Restriction of diffusion will be seen in the outer layers of active inflammation/demyelination in Balo-like lesions, in the enhancing part of ring-like lesions, and at the periphery of infiltrative-type lesions. 相似文献18.
Sherif Abdelfattah Khedr Mohamed Abdelfattah Hassaan Naglaa Mohamed Abdelrazek Amr yehia Sakr 《The Egyptian Journal of Radiology and Nuclear Medicine》2012
Purpose
To evaluate the diagnostic impact of echo planar DW imaging in distinguishing benign from malignant musculoskeletal soft-tissue masses using ADC mapping as a quantitative assessment tool.Patients and methods
We evaluated 73 tumors (21 bone tumors and 52 soft-tissue tumors). MR examinations were performed with a 1.5-T system. Diffusion-weighted single-shot EPI images were obtained in all patients. Apparent diffusion coefficients (ADCs) were calculated by using b factors of 0 and 1000 s/mm2. ADC value measurements were compared with the histopathological findings.Results
The average ADC of benign tumors was 1.86 ± 0.67 × 10−3 mm2/s, and that of malignant soft-tissue tumors was 0.97 ± 0.35 × 10−3 mm2/s. ADC value of malignant tumors was significantly lower than that of the benign tumor group (p < 0.0001). The highest ADC value was seen in the case of ganglion cyst (2.8 ± 0.23 × 10−3 mm2/s) and cystic neurofibroma (2.5 ± 0.04 × 10−3 mm2/s), and juxta cortical enchondroma (2.65 ± 0.36 × 10−3 mm2/s) while the lowest one was seen in aggressive fibromatosis (0.37 ± 0.05 × 10−3 mm2/s). For malignant soft-tissue masses, the highest ADC value was seen in mesenchymal chondrosarcoma (2.1 ± 0.32) liposarcoma (intermediate grade) (1.4 ± 0.21) while the lowest ADC value was seen in fibrosarcoma (high grade) (0.78 ± 0.14).Conclusion
MR diffusion provides additional information to the routine MRI sequences rendering it an effective non-invasive tool in differentiating between benign and malignant soft-tissue tumors. 相似文献19.
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20.
Ghada K. Gouhar El-Sayed H. Zidan 《The Egyptian Journal of Radiology and Nuclear Medicine》2011,42(1):93-99