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1.
Gourtsoyianni S Papanikolaou N Yarmenitis S Maris T Karantanas A Gourtsoyiannis N 《European radiology》2008,18(3):486-492
The purpose of this study was to measure apparent diffusion coefficient values of normal liver parenchyma and focal liver
lesions utilizing a respiratory gated diffusion sequence with multiple b-values and to investigate whether apparent diffusion
coefficient (ADC) measurements may be utilized to characterize and differentiate between malignant and benign focal hepatic
lesions. Thirty-eight consecutive patients underwent MRI of the liver including diffusion-weighted imaging (DWI). A single-shot
echo planar imaging sequence was applied in coronal orientation with multiple b-values (0, 50, 500, 1,000 s/mm2) and respiratory gating. ADC values were recorded on corresponding maps utilizing region of interest measurements in patients
with benign (group A), malignant (group B) focal lesions and liver parenchyma (group C). Statistical analysis was applied
to check whether differences in mean ADC values were significant (p<0.05). No focal lesions were detected in 11 patients,
with a mean ADC value (CI 95%) of liver parenchyma 1.25×10−3 mm2/s (1.21×10−3 mm2/s−1.29×10−3 mm2/s). Differences in mean ADC of liver parenchyma between group A and B were not significant (p=0.054, 1.30×10−3 mm2/s and 1.31×10−3 mm2/s, respectively). Mean ADC value (95% CI) of 22 benign lesions found in 18 patients was 2.55×10−3 mm2/s (2.35×10−3 mm2/s−2.74×10−3 mm2/s), while the mean ADC value (95% CI) of 16 malignant lesions recorded in 9 patients was 1.04×10−3 mm2/s (0.9×10−3 mm2/s−1.17×10−3 mm2/s). The difference between mean ADC values of benign and malignant focal lesions was statistically significant (p<0.0001).
Respiratory gated diffusion-weighted imaging in the liver is technically feasible. Apparent diffusion coefficient measurements
can be useful in differentiating malignant from benign focal liver lesions. 相似文献
2.
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
3.
Aine Sakurada Taro Takahara Thomas C. Kwee Tomohiro Yamashita Seiji Nasu Tomohiko Horie Marc Van Cauteren Yutaka Imai 《European radiology》2009,19(6):1461-1469
The purpose of this study was to assess the value of diffusion-weighted magnetic resonance imaging (DWI) in detecting esophageal
cancer and assessing lymph-node status, compared with histopathological results. DWI was prospectively performed in 24 consecutive
patients with esophageal cancer, using the diffusion-weighted whole-body imaging with background body signal suppression (DWIBS)
sequence. DWIBS images were fused with T2-weighted images, and independently and blindly evaluated by three board-certified
radiologists, regarding primary tumor detectability and lymph-node status. Apparent diffusion coefficients (ADCs) of the primary
tumor and lymph nodes were also measured. Average primary tumor detection rate was 49.4%, average patient-based sensitivity
and specificity for the detection of lymph-node metastasis were 77.8 and 55.6%, and average lymph-node group-based sensitivity
and specificity were 39.4 and 92.6%. There were no interobserver differences among the three readers (P < 0.0001). Mean ADC of detected primary tumors was 1.26 ± 0.29×10−3 mm2/s. Mean ADC of metastatic lymph nodes (1.46 ± 0.35×10−3 mm2/s) was significantly higher (P < 0.0001) than that of nonmetastatic lymph nodes (1.15 ± 0.24 mm2/s), but ADCs of both groups overlapped. In conclusion, this study suggests that DWI only has a limited role in detecting
esophageal cancer and nodal staging. 相似文献
4.
Bruegel M Holzapfel K Gaa J Woertler K Waldt S Kiefer B Stemmer A Ganter C Rummeny EJ 《European radiology》2008,18(3):477-485
The aim of this study was to determine apparent diffusion coefficients (ADCs) of focal liver lesions on the basis of a respiratory
triggered diffusion-weighted single-shot echo-planar MR imaging sequence (DW-SS-EPI) and to evaluate whether ADC measurements
can be used to characterize lesions. One hundred and two patients with focal liver lesions [11 hepatocellular carcinomas (HCC),
82 metastases, 4 focal nodular hyperplasias (FNH), 56 hemangiomas and 51 cysts; mean size, 16.6 mm; range 5–92 mm] were examined
on a 1.5-T system using respiratory triggered DW-SS-EPI (b-values: 50, 300, 600 s/mm2). Results were correlated with histopathologic data and follow-up imaging. The ADCs of different lesion types were compared,
and lesion discrimination using optimal thresholds for ADCs was evaluated. Mean ADCs (×10−3mm2/s) were 1.24 and 1.04 for normal and cirrhotic liver parenchyma and 1.05, 1.22, 1.40, 1.92 and 3.02 for HCCs, metastases,
FNHs, hemangiomas and cysts, respectively. Mean ADCs differed significantly for all lesion types except for comparison of
metastases with HCCs and FNHs. Overall, 88% of lesions were correctly classified as benign or malignant using a threshold
value of 1.63 × 10−3mm2/s. Measurements of the ADCs of focal liver lesions on the basis of a respiratory triggered DW-SS-EPI sequence may constitute
a useful supplementary method for lesion characterization. 相似文献
5.
Savannah C. Partridge PhD Wendy B. DeMartini MD Brenda F. Kurland PhD Peter R. Eby MD Steven W. White BS Constance D. Lehman MD PhD 《Journal of magnetic resonance imaging : JMRI》2010,31(3):562-570
Purpose:
To investigate the diagnostic performance of diffusion‐weighted imaging (DWI) for mammographically and clinically occult breast lesions.Materials and Methods:
The study included 91 women with 118 breast lesions (91 benign, 12 ductal carcinoma in situ [DCIS], 15 invasive carcinoma) initially detected on dynamic contrast‐enhanced magnetic resonance imaging (DCE‐MRI) and assigned BI‐RADS category 3, 4, or 5. DWI was acquired with b = 0 and 600 s/mm2. Lesion visibility was assessed on DWI. Apparent diffusion coefficient (ADC) values were compared between malignancies, benign lesions, and normal (no abnormal enhancement on DCE‐MRI) breast tissue, and the diagnostic performance of DWI was assessed based on ADC thresholding.Results:
Twenty‐four of 27 (89%) malignant and 74/91 (81%) benign lesions were hyperintense on the b = 600 s/mm2 diffusion‐weighted images. Both DCIS (1.33 ± 0.19 × 10?3 mm2/s) and invasive carcinomas (1.30 ± 0.27 × 10?3mm2/s) were lower in ADC than benign lesions (1.71 ± 0.43 × 10?3mm2/s; P < 0.001), and each lesion type was lower in ADC than normal tissue (1.90 ± 0.38 × 10?3mm2/s, P ≤ 0.001). Receiver operating curve (ROC) analysis showed an area under the curve (AUC) of 0.77, and sensitivity = 96%, specificity = 55%, positive predictive value (PPV) = 39%, and negative predictive value (NPV) = 98% for an ADC threshold of 1.60 × 10?3mm2/s.Conclusion:
Many mammographically and clinically occult breast carcinomas were visibly hyperintense on diffusion‐weighted images, and ADC enabled differentiation from benign lesions. Further studies evaluating DWI while blinded to DCE‐MRI are necessary to assess the potential of DWI as a noncontrast breast screening technique. J. Magn. Reson. Imaging 2010;1:562–570. © 2010 Wiley‐Liss, Inc.6.
Objective
To assess the role of DWI and ADC in differentiating between benign and malignant breast lesions.Materials and methods
51 patients (age range 24–66 years; mean age 48 years) were included in our study. MRI was done using bilateral fat-suppressed T2- weighted fast spin-echo, STIR, axial T1-weighted fast spin-echo. DWI series were acquired using echo planar imaging pulse sequences incorporated with diffusion gradients and finally dynamic contrast enhancement study was done.Results
Sixty three lesions were detected in 51 patients included in our study. Twenty one lesions were malignant, three lesions were intermediate and twenty two lesions were fibroadenoma according to the final histopathological study and seventeen lesions were breast cysts. A total of 21 lesions showed lower ADC values than benign lesions and were in the range of 0.76–1.29 × 10−3 mm2/s and were diagnosed as malignant breast lesions. The sensitivity and specificity for DWI in the differentiating malignant from benign breast lesions were calculated and showed 95.4% and 97.5%, respectively.Conclusion
DWI is easy to obtain in short scan time and easy to evaluate, and ADC values can differentiate between benign and malignant breast lesions with high sensitivity and specificity. 相似文献7.
Chunling Liu Changhong Liang Zaiyi Liu Shuixing Zhang Biao Huang 《European journal of radiology》2013
Objectives
To obtain perfusion as well as diffusion information in normal breast tissues and breast lesions from intravoxel incoherent motion (IVIM) imaging with biexponential analysis of multiple b-value diffusion-weighted imaging (DWI) and compare these parameters to apparent diffusion coefficient (ADC) obtained with monoexponential analysis in their ability to discriminate benign lesions and malignant tumors.Materials and methods
In this prospective study, informed consent was acquired from all patients. Eighty-four patients with 40 malignant tumors, 41 benign lesions, 30 simple cysts and 39 normal breast tissues were imaged at 1.5 T utilizing contrast-enhanced magnetic resonance imaging (MRI) and DWI using 12 b values (range: 0–1000 s/mm2). Tissue diffusivity (D), perfusion fraction (f) and pseudo-diffusion coefficient (D*) were calculated using segmented biexponential analysis. ADC (b = 0 and 1000 s/mm2) was calculated with monoexponential fitting of the DWI data. D, f, D* and ADC values were obtained for normal breast tissues, simple cysts, benign lesions and malignant tumors. Receiver operating characteristic analysis was performed for all DWI parameters.Results
There was good interobserver agreement on the measurements between the 2 observers. D values were significantly different among malignant tumors, benign lesions, simple cysts and normal breast tissues (P = 0.000) and it was the same result for f, D* and ADC values. Further comparisons of these 4 parameters between every single pair were as the following. D and ADC values of malignant tumors were significantly smaller than those of benign lesions, simple cysts and normal tissues (P = 0.000, respectively). The f value of malignant tumors was significantly higher than that of benign lesions, simple cysts and normal breast tissues (P = 0.001, P = 0.000, and P = 0.000). D and ADC values demonstrated higher sensitivity and specificity in differentiating benign lesions and malignant tumors, with area under the curve (AUC) of 0.952 and 0.945, respectively, while f and D* with the lower AUC of 0.723 and 0.630, respectively. Combining f and D values had a sensitivity up to 98.75%.Conclusion
DWI response curves in malignant tumors, benign lesions and normal fibroglandular tissues are found to be biexponential fit in comparison with the monoexponential fit for simple cysts. IVIM provides separate quantitative measurement of D for cellularity and f and D* for vascularity and is helpful for differentiation between benign and malignant breast lesions. 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.
Luísa Nogueira Sofia Brandão Eduarda Matos Rita Gouveia Nunes Joana Loureiro Isabel Ramos Hugo Alexandre Ferreira 《European radiology》2014,24(6):1197-1203
Objectives
To evaluate diffusion-weighted imaging (DWI) and diffusion kurtosis imaging (DKI) in the differentiation and characterisation of breast lesions.Methods
Thirty-six women underwent breast magnetic resonance imaging (MRI) including a DWI sequence with multiple b-values (50–3,000 s/mm2). Mean values for apparent diffusion coefficient (ADC), mean diffusivity (MD) and mean kurtosis (MK) were calculated by lesion type and histological subtype. Differences and correlation between parameters were determined.Results
Forty-four lesions were found. There were significant differences between benign and malignant lesions for all parameters (ADC, p?=?0.017; MD, p?=?0.028; MK, p?=?0.017). ADC and MD were higher for benign (1.96?±?0.41?×?10?3 and 2.17?±?0.42?×?10?3 mm2/s, respectively) than for malignant lesions (1.33?±?0.18?×?10?3 and 1.52?±?0.50?×?10?3 mm2/s). MK was higher for malignant (0.61?±?0.27) than benign lesions (0.37?±?0.18). We found differences between invasive ductal carcinoma (IDC) and fibroadenoma (FA) for all parameters (ADC, MD and MK): p?=?0.016, 0.022 and 0.016, respectively. FA and fibrocystic change (FC) showed differences only in MK (p?=?0.016).Conclusions
Diffusion in breast lesions follows a non-Gaussian distribution. MK enables differentiation and characterisation of breast lesions, providing new insights into microstructural complexity. To confirm these results, further investigation in a broader sample should be performed.Key Points
? The diffusion kurtosis model provides new information regarding breast lesions ? MD and MK are valid parameters to characterise tissue microstructure ? MK enables improved lesion differentiation ? MK is able to differentiate lesions that display similar ADC values 相似文献10.
Reham Ali Abd El-Aleem Eman Abo El-Hamd Hosam A. Yousef Moustafa E.M. Radwan Rabab Ahmed A. Mohammed 《The Egyptian Journal of Radiology and Nuclear Medicine》2018,49(1):272-280
Objective
To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) with calculation of the apparent diffusion coefficient (ADC) value in characterizing benign and malignant breast lesions.Patients and methods
The imaging data of thirty-nine female patients (mean age 48 years) who underwent breast MRI using conventional pulse sequences. DW-MRI and dynamic contrast enhanced (DCE) study were all analyzed and correlated with the results of histopathological evaluation.Results
Forty-six breast lesions were detected in the thirty-nine patients of the study. According to the histopathological analysis, there were 27 malignant lesions (58.69%) and 19 benign lesions (41.31%). The malignant lesions showed a mean ADC value of 0.93?±?0.42?×?10?3?mm2/s. and the benign lesions showed a mean ADC value of 1.54?±?0.43?×?10?3?mm2/s. The receiver operating characteristic (ROC) curve could identify an ADC 1.26?×?10?3?mm2/s as a cut-off value to differentiate between benign and malignant lesions with sensitivity and specificity of 89% and 94.7% respectively.Conclusion
DW-MRI is useful for differentiating malignant and benign breast lesions, increasing the specificity of breast MRI. DW-MRI doesn't cause significant increase in the total examination time and is recommended to be incorporated in the standard breast MRI protocol. 相似文献11.
Diffusion-weighted MRI in cystic or necrotic intracranial lesions 总被引:11,自引:2,他引:9
Our purpose was to investigate the signal intensities of cystic or necrotic intracranial lesions on diffusion-weighted MRI
(DWI) and measure their apparent diffusion coefficients (ADC). We examined 39 cystic or necrotic intracranial lesions in 33
consecutive patients: five malignant gliomas, seven metastases, two other necrotic tumours, a haemangioblastoma, three epidermoids,
an arachnoid cyst, seven pyogenic abscesses, 12 cases of cysticercosis and one of radiation necrosis. DWI was performed on
a 1.5 T unit using a single-shot echo-planar spin-echo pulse sequence with b 1000 s/mm2. The signal intensity of the cystic or necrotic portion on DWI was classified by visual assessment as markedly low (as low
as cerebrospinal fluid), slightly lower than, isointense with, and slightly or markedly higher than normal brain parenchyma.
ADC were calculated in 31 lesions using a linear estimation method with measurements from b of 0 and 1000 s/mm2. The cystic or necrotic portions of all neoplasms (other than two metastases) gave slightly or markedly low signal, with
ADC of more than 2.60 × 10−3 mm2/s. Two metastases in two patients showed marked high signal, with ADC of 0.50 × 10−3 mm2/s and 1.23 × 10−3 mm2/s, respectively. Epidermoids showed slight or marked high signal, with ADC of less than 1.03 × 10−3 mm2/s. The arachnoid cyst gave markedly low signal, with ADC of 3.00 × 10−3 mm2/s. All abscesses showed marked high signal, with ADC below 0.95 × 10−3 mm2/s. The cases of cysticercosis showed variable signal intensity; markedly low in five, slightly low in three and markedly
high in four.
Received: 17 November 1999/Accepted: 3 February 2000 相似文献
12.
Reiji Sugita Tetsuro Yamazaki Akemi Furuta Kei Itoh Naotaka Fujita Shoki Takahashi 《European radiology》2009,19(7):1794-1798
The aim of this preliminary study was to retrospectively evaluate the usefulness of high b-value diffusion-weighted MR imaging
(DWI) in the detection of gallbladder carcinoma. Fifteen patients with gallbladder carcinoma and 14 other patients were included
in this study. All patients and subjects underwent DWI, and images were evaluated by two radiologists. The area under the
receiver operating characteristic curve (AUC), apparent diffusion coefficient (ADC) measurement, sensitivity and specificity
were calculated. An AUC yielded 0.980 (95% CI, 0.850–0.999) and 0.941 (95% CI, 0.791–0.990) for the two radiologists. The
mean sensitivity and specificity were 83.3% and 100%, respectively. The mean ADC value of gallbladder carcinoma was (1.28 ± 0.41)×10−3 mm2/s and that of control gallbladder lesions was (1.92 ± 0.21)×10−3 mm2/s (P < 0.01). According to the results of our preliminary study, high b-value DWI might be a useful tool for detecting gallbladder
carcinoma by measuring the ADC value and direct visual assessment. 相似文献
13.
Introduction Epidural spinal cord compression is one of the most critical emergency conditions requiring medical attention and requires
prompt and adequate treatment. The aim of our study was to assess the role of diffusion-weighted magnetic resonance (MR) imaging
(DWI) in the diagnosis and differentiation of epidural spinal lesions.
Methods Three patients with epidural lymphoma, two with sarcoma and three with epidural metastatic disease were imaged on a 1.5T MRI
unit. DWI was performed using navigated, interleaved, multi-shot echo planar imaging (IEPI). Three region of interest (ROI)-measurements
were obtained on corresponding apparent diffusion coefficient (ADC) maps, and the mean ADC value was used for further analysis.
The cellularity of tumors was determined as the N/C ratio (nucleus/cytoplasma ratio) from histological samples. The ADC values
and N/C ratios of lesions were compared using a Kruskal-Wallis test.
Results The mean ADC of the lymphomas was 0.66 × 10−3 mm2/s, that of the sarcomas was 0.85 × 10−3 mm2/s and the ADC of the metastatic lesions was 1.05 × 10−3 mm2/s; however, the differences were not statistically significant. Mean N/C ratios in the lymphoma, sarcomas and metastases
were 4:1, 2:1, and 2.6:1, respectively, with a statistically significant difference between the groups (p < 0.025).
Conclusion Although not statistically significant due to the small patient sample, our results clearly show a tendency toward decreased
diffusivity in neoplastic lesions with higher cellularity. The data from our study suggest that DWI is a feasible and potentially
useful technique for the evaluation of epidural lesions that cause spinal cord compression on a per-patient basis. 相似文献
14.
Abdel Razek AA Gaballa G Elhawarey G Megahed AS Hafez M Nada N 《European radiology》2009,19(1):201-208
We aimed to assess the clinical usefulness of the ADCs calculated from diffusion-weighted echo-planar MR images in the characterization
of pediatric head and neck masses. This study included 78 pediatric patients (46 boys and 32 girls aged 3 months–15 years,
mean 6 years) with head and neck mass. Routine MR imaging and diffusion-weighted MR imaging were done on a 1.5-T MR unit using
a single-shot echo-planar imaging (EPI) with a b factor of 0.500 and 1,000 s mm−2. The ADC value was calculated. The mean ADC values of the malignant tumours, benign solid masses and cystic lesions were
(0.93 ± 0.18) × 10−3, (1.57 ± 0.26) × 10–3 and (2.01 ± 0.21 )× 10–3 mm2 s−1, respectively. The difference in ADC value between the malignant tumours and benign lesions was statistically significant
(p < 0.001). When an apparent diffusion coefficient value of 1.25 × 10–3 mm2 s−1 was used as a threshold value for differentiating malignant from benign head and neck mass, the best results were obtained
with an accuracy of 92.8%, sensitivity of 94.4%, specificity of 91.2%, positive predictive value of 91% and negative predictive
value of 94.2%. Diffusion-weighted MR imaging is a new promising imaging approach that can be used for characterization of
pediatric head and neck mass. 相似文献
15.
Tomohiro Namimoto Yasuyuki Yamashita Kazuo Awai Takeshi Nakaura Yumi Yanaga Toshinori Hirai Tetsuo Saito Hidetaka Katabuchi 《European radiology》2009,19(11):2756-2764
The objective of our study was to compare diffusion-weighted imaging (DWI) alone and DWI combined with T2-weighted MRI for
the differentiation of uterine sarcomas from benign leiomyomas. T2-weighted imaging and DWI were performed in 103 patients
with 103 myometrial tumours, including 8 uterine sarcomas and 95 benign leiomyomas on 3-T MR imaging. The signal intensity
(SI) of the tumour on T2-weighted images was quantified as the tumour–myometrium contrast ratio (TCR) by using the following
formula: (SItumour − SImyometrium)/SImyometrium. The TCR or apparent diffusion coefficient (ADC) value alone and then the ADC value combined with T2-weighted imaging were
evaluated for differentiation between sarcomas and leiomyomas. The mean ADC value of sarcomas was 0.86 ± 0.11 × 10−3 m2/s, which was significantly lower than that of leiomyomas 1.18 ± 0.24 × 10−3 m2/s; however, there was a substantial overlap. The mean TCR of sarcomas was 0.66 ± 0.71, which was significantly higher than
that of the leiomyomas, –0.37 ± 0.34; however, again, there was a considerable overlap. When ADC was less than 1.05 × 10−3 mm2/s and TCR was greater than 0 this condition was considered to confirm a sarcoma; a combination of ADC and TCR achieved a
significant improvement without any overlap between sarcomas and leiomyomas (sensitivity 100%, specificity 100%). Our preliminary
results indicate that combined DWI and T2-weighted MR imaging is better than DWI alone in the differentiation of uterine sarcomas
from benign leiomyomas. 相似文献
16.
Role of diffusion-weighted imaging in prediction of nipple-areolar complex invasion by breast cancer
The aim of this workThe aim of this work was to estimate the role of diffusion-weighted imaging (DWI) in predicting malignant invasion of the nipple-areolar complex (NAC) by underlying breast cancer.Material and methodsThis prospective study included 70 female patients with breast cancer with a mean age of 45.8 years (range: 28–68). DWI of the breast was done for all patients. Apparent diffusion coefficient (ADC) maps were automatically constructed. The mean ADC values of NAC were independently measured by two observers who are experts in breast imaging and correlated with the results of histopathological examinations.ResultsBoth observers found a significantly lower ADC value of malignant NAC invasion (n = 18) when compared with free NAC (n = 52), with mean ADC value for malignant NAC invasion was 0.86 ± 0.35 × 10−3 mm2/s and 0.84 ± 0.08 × 10−3 mm2/s for observer one and two respectively versus mean ADC value of 1.34 ± 0.25 × 10−3 mm2/s and 1.4 ± 0.26 × 10−3 mm2/s for free NAC by observer one and two respectively (P-value =0.001). Observer one found that a cutoff ADC value of 1.05 × 0−3 mm2/s can predict malignant NAC invasion with 0.975 AUC, 92.8% accuracy, 94.4% sensitivity, and 92.3% specificity. Observer two found that a cutoff ADC value of 0.95 × 10−3 mm2/s can predict malignant NAC invasion with 0.992 AUC, 95.7% accuracy, 88.9% sensitivity, and 98.1% specificity.ConclusionDWI can predict malignant NAC invasion in patients with breast cancer. 相似文献
17.
Cosottini M Tavarelli C Del Bono L Doria G Giannelli M De Cori S Michelassi MC Bartolozzi C Murri L 《European radiology》2008,18(5):1024-1030
Progressive multifocal leukoencephalopathy (PML) is a severe demyelinating disease of the central nervous system due to JC
polyoma virus infection of oligodendrocytes. PML develops in patients with impaired T-cell function as occurs in HIV, malignancy
or immunosuppressive drugs users. Until now no imaging methods have been reported to correlate with clinical status. Diffusion-weighted
imaging (DWI) is a robust MRI tool in investigating white matter architecture and diseases. The aim of our work was to assess
diffusion abnormalities in focal white matter lesions in patients with PML and to correlate the lesion load measured with
conventional MRI and DWI to clinical variables. We evaluated eight patients with a biopsy or laboratory-supported diagnosis
of PML. All patients underwent MRI including conventional sequences (fluid attenuated inversion recovery-FLAIR) and DWI. Mean
diffusivity (MD) maps were used to quantify diffusion on white matter lesions. Global lesion load was calculated by manually
tracing lesions on FLAIR images, while total, central core and peripheral lesion loads were calculated by manually tracing
lesions on DWI images. Lesion load obtained with the conventional or DWI-based methods were correlated with clinical variables
such as disease duration, disease severity and survival. White matter focal lesions are characterized by a central core with
low signal on DWI images and high MD (1.853 × 10−3 mm2/s), surrounded by a rim of high signal intensity on DWI and lower MD (1.1 × 10−3 mm2/s). The MD value of normal-appearing white matter is higher although not statistically significant (0.783 × 10−3 mm2/s) with respect to control subjects (0.750 × 10−3 mm2/s). Inter-rater correlations of global lesion load between FLAIR (3.96%) and DWI (3.43%) was excellent (ICC =0.87). Global
lesion load on FLAIR and DWI correlates with disease duration and severity (respectively, p = 0.037, p = 0.0272 with Karnofsky
scale and p = 0.0338 with EDSS on FLAIR images; p = 0.043, p = 0.0296 with Karnofsky scale and p = 0.0365 with EDSS on DW
images). Central core lesion load on DWI correlates with disease duration and severity (respectively p = 0.043, p = 0.0103
with Karnofsky scale and p = 0.0112 with EDSS), while peripheral lesion load does not correlate with any clinical variable.
The global lesion load in PML correlates with disease duration and severity. DWI images, which can distinguish within lesions
a central core from a peripheral rim, reveal that a larger central core component correlates to a worsened clinical status
and longer disease duration. On the other hand the peripheral rim lesion load visualized on DWI images does not correlate
with clinical variables and does not achieve obtaining further prognostic information with respect to conventional imaging. 相似文献
18.
Role of diffusion-weighted MR imaging in cervical lymphadenopathy 总被引:21,自引:0,他引:21
Abdel Razek AA Soliman NY Elkhamary S Alsharaway MK Tawfik A 《European radiology》2006,16(7):1468-1477
The role of diffusion-weighted magnetic resonance imaging (MRI) for differentiation between various causes of cervical lymphadenopathy
was evaluated. In a prospective study, 31 untreated patients (22 males and nine females, aged 5–70 years) with 87 cervical
lymph nodes underwent diffusion-weighted MRI before performance of neck dissection (n=14), surgical biopsy (n=9) or core biopsy (n=8). Diffusion-weighted MR images were acquired with a b factor of 0 and 1,000 s/mm2 using single-shot echo-planar sequence. Apparent diffusion coefficient (ADC) maps were reconstructed for all patients. The
signal intensity of the lymph nodes was assessed on images obtained at b=0 or 1,000 s/mm2 and from the ADC maps. The ADC value of lymph nodes was also calculated. On the ADC map, malignant nodes showed either low
(n=52) or mixed (n=20) signal intensity and benign nodes revealed high (n=13) or low (n=2) signal intensity. The mean ADC value of metastatic (1.09±0.11×10−3 mm2/s) and lymphomatous (0.97±0.27×10−3 mm2/s) lymph nodes was significantly lower than that of benign (1.64±0.16×10−3 mm2/s) cervical lymph nodes (P<0.04). When an ADC value of 1.38×10−3 mm2/s was used as a threshold value for differentiating malignant from benign lymph nodes, the best results were obtained with
an accuracy of 96%, sensitivity of 98%, specificity of 88%, positive predictive value of 98.5% and negative predictive value
of 83.7%. The smallest detected lymph node was 0.9 cm. In conclusion, diffusion-weighted MRI with ADC mapping is a new promising
technique that can differentiate malignant from benign lymph nodes and delineate the solid viable part of the lymph node for
biopsy. This technique provides additional useful physiological and functional information regarding characterization of cervical
lymph nodes. 相似文献
19.
Takao Taniguchi Hisato Kobayashi Koji Nishikawa Etsushi Iida Yoshihiro Michigami Emiko Morimoto Rikiya Yamashita Ken Miyagi Motozumi Okamoto 《Japanese journal of radiology》2009,27(3):138-142
Purpose The aim of this study was to investigate the usefulness of diffusion-weighted magnetic resonance imaging (DWI MRI) for the
diagnosis and evaluation of autoimmune pancreatitis (AIP).
Materials and methods A total of 4 consecutive patients with AIP, 5 patients with chronic alcoholic pancreatitis (CP), and 13 patients without pancreatic
disease (controls) were studied. DWI was performed in the axial plane with spin-echo echo-planar imaging single-shot sequence.
Apparent diffusion coefficients (ADCs) were measured in circular regions of interest in the pancreas. In AIP patients, abdominal
MRI was performed before, and 2–4 weeks after steroid treatment. Follow-up study was performed chronologically for up to 11
months in two patients. The correlation between ADCs of the pancreas and the immunoglobulin G4 (IgG4) index (serum IgG4 value/serum
IgG4 value before steroid treatment) was evaluated.
Results In the AIP patients, DWI of the pancreas showed high signal intensity, and the ADCs of the pancreas (mean ± SD: 0.97 ± 0.18
× 10−3 mm2/s) were significantly lower than those in patients with CP (1.45 ± 0.10 × 10−3 mm2/s) or the controls (1.45 ± 0.16 × 10−3 mm2/s) (Mann-Whitney U-test, P < 0.05). In one AIP patient with focal swelling of the pancreas head that appeared to be a mass, DWI showed high signal intensity
throughout the pancreas, indicating diffuse involvement. The ADCs of the pancreas and IgG4 index were significantly inversely
correlated (Spearman’s rank correlation coefficient, r
s = −0.80, P < 0.05).
Conclusion Autoimmune pancreatitis showed high signal intensity on DWI, which improved after steroid treatment. ADCs reflected disease
activity. Thus, diffusion-weighted MRI might be useful for diagnosing AIP, determining the affected area, and evaluating the
effect of treatment.
T. Taniguchi and H. Kobayashi contributed equally to this study 相似文献
20.
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