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1.
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
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.
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
4.
Hoda Abdel Kareem Ahmed Abdel Rady 《The Egyptian Journal of Radiology and Nuclear Medicine》2018,49(4):903-907
Background
Early diagnosis is crucial in management of pancreatic malignancy. DWMRI could be used in differentiating pancreatic lesions and judge about tumor aggressiveness.Patients & methods
Fifty patients were included in this prospective study with mean age ±43?years. Histopathology & follow up clinical results revealed 34 malignant and 16 benign lesions. All patients underwent non-contrast MRI examination and DWI at different b-values with ADC value measurements.Results
Conventional MRI poorly diagnosed pancreatic focal lesions with 79% Sensitivity, 68% specificity & 76% accuracy. In DWI with high b-value of 1000, 31/34 malignant lesions showed restricted diffusion with low ADC value (≤1.5?×?10?3?mm2/s) while 14/16 benign lesions showed mixed diffusion with higher ADC values (≥1.7?×?10?3?mm2/s). DWI at high b-value of 1000 with chosen ADC value of 1.5 as a cut-off value revealed high sensitivity (91.18%), 87.5% specificity, 93.84% PPV, 82.35% NPV and 90% accuracy in differentiating benign from malignant pancreatic lesions.Conclusion
DWMRI found to be a simple and non-invasive tool that aid in the diagnosis of pancreatic pathology with recommended high b-value and a cut-off ADC value of 1.5 that approved the highest sensitivity & specificity in differentiating benign from malignant pancreatic focal lesions. 相似文献5.
Quantitative diffusion-weighted MR imaging in the differential diagnosis of breast lesion 总被引:3,自引:0,他引:3
Marini C Iacconi C Giannelli M Cilotti A Moretti M Bartolozzi C 《European radiology》2007,17(10):2646-2655
The role of diffusion-weighted magnetic resonance imaging (DWI) to differentiate breast lesions in vivo was evaluated. Sixty
women (mean age, 53 years) with 81 breast lesions were enrolled. A coronal echo planar imaging (EPI) sequence sensitised to
diffusion (b value=1,000 s/mm2) was added to standard MR. The mean diffusivity (MD) was calculated. Differences in MD among cysts, benign lesions and malignant
lesions were evaluated, and the sensitivity and specificity of DWI to diagnose malignant and benign lesions were calculated.
The diagnosis was 18 cysts, 21 benign and 42 malignant nodules. MD values (mean±SD ×10−3 mm2/s) were (1.48±0.37) for benign lesions, (0.95±0.18) for malignant lesions and (2.25±0.26) for cysts. Different MD values
characterized different malignant breast lesion types. A MD threshold value of 1.1×10−3 mm2/s discriminated malignant breast lesions from benign lesions with a specificity of 81% and sensitivity of 80%. Choosing a
cut-off of 1.31×10−3 mm2/s (MD of malignant lesions -2 SD), the specificity would be 67% with a sensitivity of 100%. Thus, MD values, related to tumor
cellularity, provide reliable information to differentiate malignant breast lesions from benign ones. Quantitative DWI is
not time-consuming and can be easily inserted into standard clinical breast MR imaging protocols. 相似文献
6.
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
7.
E. A. Lassel R. Rao C. Schwenke S. O. Schoenberg H. J. Michaely 《European radiology》2014,24(1):241-249
Objectives
Contrast-enhanced MRI can only distinguish to a limited extent between malignant and benign focal renal lesions. The aim of this meta-analysis is to review renal diffusion-weighted imaging (DWI) to compare apparent diffusion coefficient (ADC) values for different renal lesions that can be applied in clinical practice.Methods
A PubMed search was performed to identify relevant articles published 2004–2011 on renal DWI of focal renal lesions. ADC values were extracted by lesion type to determine whether benign or malignant. The data table was finalised in a consensus read. ADC values were evaluated statistically using meta-regression based on a linear mixed model. Two-sided P value <5 % indicated statistical significance.Results
The meta-analysis is based on 17 studies with 764 patients. Renal cell carcinomas have significant lower ADC values than benign tissue (1.61?±?0.08?×?10-3 mm2/s vs 2.10?±?0.09?×?10-3 mm2/s; P?<?0.0001). Uroepithelial malignancies can be differentiated by lowest ADC values (1.30?±?0.11?×?10-3 mm2/s). There is a significant difference between ADC values of renal cell carcinomas and oncocytomas (1.61?±?0.08?×?10-3 mm2/s vs 2.00?±?0.08?×?10-3 mm2/s; P?<?0.0001).Conclusions
Evaluation of ADC values can help to determine between benign and malignant lesions in general but also seems able to differentiate oncocytomas from malignant tumours, hence potentially reducing the number of unnecessarily performed nephrectomies.Key Points
? This meta-analysis assesses the role of diffusion-weighted MRI in renal lesions. ? ADC values obtained by DW MRI have been compared for different renal lesions. ? ADC values can help distinguish between benign and malignant tumours. ? Differentiating oncocytomas from malignant tumours can potentially reduce inappropriate nephrectomies. 相似文献8.
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
9.
Frank H. Miller MD Nancy Hammond MD Aheed J. Siddiqi MD Sagar Shroff BS Gaurav Khatri MD Yi Wang MD Laura B. Merrick BA Paul Nikolaidis MD 《Journal of magnetic resonance imaging : JMRI》2010,32(1):138-147
Purpose:
To evaluate apparent diffusion coefficient (ADC) values for characterization of a variety of focal liver lesions and specifically for differentiation of solid benign lesions (focal nodular hyperplasia [FNH] and adenomas) from solid malignant neoplasms (metastases and hepatocellular carcinoma [HCC]) in a large case series.Materials and Methods:
A total of 542 lesions in 382 patients were evaluated. ADC values were measured in 166 hemangiomas, 112 hepatomas, 107 metastases, 95 cysts, 10 abscesses, 43 FNH, and nine adenomas. ADCs of 1.5 and 1.6 (×10?3 mm2/second) were selected as threshold values to separate benign and malignant lesions. Sensitivity, specificity, positive, and negative predictive values (PPV, NPV) were calculated. Comparisons were carried out with studentized range test.Results:
There was high interobserver agreement in ADC measurements for all lesion types. The mean ADCs for cysts was 3.40 (×10 ?3 mm2/second), hemangiomas 2.26, FNH 1.79, adenomas 1.49, abscesses 1.97, HCC 1.53, and metastases 1.50. The mean ADC for benign lesions was 2.50 and for malignant lesions was 1.52. Cysts were easily distinguished from other lesions. There was, however, overlap between solid benign and malignant lesions.Conclusion:
Benign lesions have higher mean ADC values than malignant lesions. However, ADC values of solid benign lesions (FNH and adenomas) are similar to malignant lesions (metastases, HCC) limiting the value of diffusion weighted imaging (DWI) for differentiating solid liver masses. J. Magn. Reson. Imaging 2010;32:138–147. © 2010 Wiley‐Liss, Inc.10.
Purpose
This study was done to assess the role of diffusion-weighted magnetic resonance (MR) imaging in assessing malignant versus benign skull lesions.Materials and methods
A retrospective analysis was undertaken of 45 patients (26 male, 19 female; age range 14?C68 years, mean age 39 years) with skull-base lesions. Diffusion-weighted MR images were acquired with a bfactor of 500 and 1,000 s/mm2 using single-shot echoplanar imaging. Apparent diffusion coefficient (ADC) maps were reconstructed, and the ADC value of the lesion was calculated.Results
The mean ADC value of malignant tumours was (1.002±0.21)×10?3 mm2/s and that of benign tumours was (1.63±0.29)×10?3 mm2/s. There was a statistically significant difference (p=0.001) in the ADC value of malignant skull-base tumours versus benign lesions. Selection of (1.3)×10?3mm2/s as a threshold value of ADC for differentiating benign from malignant tumours yielded the best result, with an accuracy of 94%, sensitivity of 94%, specificity of 93%, positive predictive value of 93%, negative predictive value of 94% and area under the curve of 0.932.Conclusions
We conclude that diffusion-weighted MR imaging is a promising, noninvasive approach that can be used to characterise skull-base lesions in that it can help differentiate malignant tumours from benign lesions and evaluate the pathological grading of malignant tumours. 相似文献11.
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12.
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13.
PurposeTo evaluate the efficacy of apparent diffusion coefficient (ADC) calculation in differentiation between malignant and benign thyroid nodules.Methods and materialsA prospective study was conducted in 52 patients. Diffusion-weighted echoplanar imaging was performed and b factors were taken as 0 and 400 s/mm2.ResultsThe mean ADC value for malignant thyroid nodules was 0.829±0.179×10?3 mm2/s and that for benign thyroid nodules was 1.984±0.482×10?3 mm2/s. The mean ADC value for malignant nodules was significantly lower than that for benign nodules (P=.0001).ConclusionADC value calculation is an effective method in differentiation of malignant thyroid nodules from benign ones. 相似文献
14.
The aim of this study was to retrospectively measure and compare pancreatic apparent diffusion coefficient (ADC) in patients
with acute pancreatitis (AP) with aged matched controls who underwent diffusion weighted imaging (DWI). The institutional
review board approved this retrospective Health Insurance Portability and Accountability Act compliant study with a waiver
for informed consent. Pancreatic ADC values from 27 patients with a clinical diagnosis of AP and 38 normal age-matched controls
evaluated with DWI (b = 0 and 800 mm2/s) were retrospectively and independently measured by two radiologists. The ADCs were compared between the groups and between
each of the pancreatic segments in the normal group. Inter-observer reliability was calculated and receiver operating characteristic
analysis was used to determine the sensitivity and specificity of DW imaging in the diagnosis of acute pancreatitis. P < 0.05 was considered statistically significant. The ICC for inter-observer reliability was 0.98 in the control and 0.97
in the AP group. The mean pancreatic ADC in the AP group (1.32 × 10−3 mm2/s ± 0.13) was significantly lower than in the normal group (1.77 × 10−3 mm2/s ± 0.32). There was no significant difference in mean ADCs between each of the pancreatic segments in the controls. A threshold
ADC value of 1.62 × 10–3 mm2/s yielded a sensitivity of 93% and specificity of 87% for detecting acute pancreatitis for b values of 0 and 800 s/mm2. Pancreatic ADCs are significantly lower in patients with AP than normal controls. 相似文献
15.
Irfan Celebi Abdullah Soydan Mahmutoglu Ayhan Ucgul Sıtkı Mert Ulusay Tulay Basak Muzaffer Basak 《Clinical imaging》2013,37(2):232-238
We evaluated the quantitative diffusion-weighted magnetic resonance imaging (DW-MRI) for parotid masses. Seventy-five patients with 81 focal parotid masses were included. Following DW-MRI, 73 masses underwent surgical biopsy/resection, 6 underwent ultrasonography-guided fine-needle aspiration, and 2 underwent both procedures. The mean apparent diffusion coefficient (ADC) of benign tumors (n= 49, 1.72×10? 3 mm2/s) was higher than that of malignant tumors (n= 32, 1.05×10? 3 mm2/s) (P<.001). ADC was 2.15×10? 3 mm2/s for pleomorphic adenomas, which was higher than that for other tumors (P<.001 for all). ADC cutoff was 1.315 for distinguishing between pleomorphic adenomas and others including malignant tumors. Therefore, DW-MRI may be useful for distinguishing between pleomorphic adenomas and other parotid masses. 相似文献
16.
The purpose was to investigate the potential value of apparent diffusion coefficient (ADC) measurement with MRI in the assessment
of cervix cancer. Diffusion-weighted MRI was performed in 47 patients with cervical carcinoma undergoing chemoradiation therapy
and 26 normal controls on a 1.5-T system with a b-value of 600 s/mm2. FIGO stage, tumor volume, nodal status, interstitial fluid pressure (IFP) and oxygen measurements were recorded. Response
was defined as no visible tumor 3–6 months following completion of therapy. The average median ADC (mADC) of cervical carcinomas
(1.09±0.20×10−3 mm2/s) was significantly lower than normal cervix (2.09±0.46×10−3 mm2/s) (P<0.001). There was no correlation between mADC, nodal status, tumor volume, IFP or oxygen measurements. mADC was significantly
lower in FIGO stages T1b/T2a (0.986 × 10−3 mm2/s) compared to T2b (1.21×10−3 mm2/s) and T3/T4 (1.10×10−3 mm2/s) (P<0.001). In patients with squamous carcinomas the 90th percentile of ADC values was lower in responders than non-responders
(P<0.05). Median ADC in cervix carcinoma is significantly lower compared to normal cervix. ADC may have predictive value in
squamous tumors, but further long-term study will determine the ultimate clinical utility. 相似文献
17.
P. Belli M. Costantini E. Bufi A. Magistrelli G. La Torre L. Bonomo 《La Radiologia medica》2010,115(1):51-69
Purpose
The purpose of this study was to investigate the ability of diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) in the detection and characterisation of breast lesions.Materials and methods
From September 2005 to September 2007, 86 patients with breast lesions who underwent magnetic resonance imaging (MRI) in our department were included in our study. MRI was performed with a 1.5-T unit using a standard protocol including DWI sequence. For each breast lesion, the ADC value was calculated and compared with that of normal breast tissue and to the definitive pathological diagnosis. Mann-Whitney U and Kruskal-Wallis tests were used for statistical analysis.Results
A total of 126 breast lesions were detected. Pathology results revealed 100 malignant and 26 benign lesions. Mean diameter of lesions was 26.02 mm (range 4–90 mm), including 52 lesions ≤15 mm in size. Mean ADC value of normal glandular tissue was 1.55×10?3 mm2/s. Mean ADC value of malignant lesions was 0.97×10?3 mm2/s. Mean ADC value for benign lesions was 1.66×10?3 mm2/s. Benign lesions showed ADC values significantly higher than malignant lesions (p<0.0001).Conclusions
DWI provides reliable information to support MRI diagnosis of breast masses. ADC value appears a promising adjunctive parameter in distinguishing malignant from benign breast lesions. 相似文献18.
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
19.
Shintaro Ichikawa MD Utaroh Motosugi MD PhD Tomoaki Ichikawa MD PhD Katsuhiro Sano MD PhD Hiroyuki Morisaka MD Tsutomu Araki MD PhD 《Journal of magnetic resonance imaging : JMRI》2013,37(6):1371-1376
Purpose:
To compare diffusivity values between malignant and benign focal hepatic lesions using the intravoxel incoherent motion model.Materials and Methods:
This study included 84 focal hepatic lesions in 84 patients. Final diagnoses were as follows: hepatocellular carcinoma (n = 45), cholangiocarcinoma (n = 6), metastatic liver tumor (n = 3), cyst (n = 20), hemangioma (n = 5), inflammatory pseudotumor (n = 2), abscess (n = 2), and focal nodular hyperplasia (n = 1). Diffusion‐weighted images at 12 b‐values were used to obtain the diffusion coefficient of pure molecular diffusion (D), diffusion coefficient of microcirculation or perfusion‐related diffusion (D*), and perfusion‐related diffusion fraction (f). Parameters of malignant and benign focal hepatic lesions were compared using the Wilcoxon test. The diagnostic performance for distinguishing between malignant and benign hepatic lesions was also analyzed.Results:
Both the D value (1.15 ± 0.21 × 10?3 mm2/s [mean ± standard deviation]) and D* value (62.7 ±12.7 × 10?3 mm2/s) in malignant lesions was significantly lower than that in benign lesions (D value [2.46 ± 0.45× 10?3 mm2/s], P < 0.0001; D* value [87.6 ± 35.3 × 10?3 mm2/s], P = 0.0008). The f value did not differ significantly between malignant (25.0 15.1 ± 15.1%) and benign lesions (30.1 ± 16.3%).Conclusion:
D* and D values were suppressed in malignant lesions. However, the D value was more reliable for distinguishing between malignant and benign focal hepatic lesions. J. Magn. Reson. Imaging 2013;37:1371–1376. © 2012 Wiley Periodicals, Inc.20.
Ozgur Cakir Arzu Arslan Nagihan Inan Yonca Anık Tahsin Sarısoy Sevtap Gumustas Gur Akansel 《European journal of radiology》2013