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1.
PurposeTo evaluate whether diffusion tensor imaging (DTI) can be used to differentiate malignant parotid gland tumors from the benign ones.Materials and methodsThe study population comprised 59 parotid gland tumors (24 Warthin’s tumors, 19 pleomorphic adenomas, seven other benign tumors, and nine malignant tumors). Single-shot echo-planar DTI was performed with motion-probing gradients along 30 noncollinear directions (b = 1000 s/mm2) at 3.0 T. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values for benign and malignant tumors were compared using the Mann–Whitney U test. Receiver-operating characteristic (ROC) curve analysis was performed to assess the ability of the ADC and FA values to differentiate malignant tumors from the benign ones.ResultsADC values showed no significant difference between malignant (0.93 ± 0.21 × 10−3 mm2/s) and benign tumors (1.19 ± 0.50 × 10−3 mm2/s) (p = 0.225). FA values of malignant tumors were significantly higher than those of benign tumors (0.26 ± 0.06 vs. 0.17 ± 0.05, p < 0.001). The area under the ROC curve of FA was significantly greater than that under the curve of ADC (0.884 vs. 0.628, p = 0.010).ConclusionsDTI, particularly FA, can help differentiate malignant parotid gland tumors from the benign ones. 相似文献
2.
Ahmed Elsammak S.M Shehata Mona Abulezz Ghada Gouhar 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(3):751-759
Objectives
To assess the role of DW-MRI and ADC values in distinguishing benign from malignant endometrial disorders.Patients and methods
Pelvic ultrasound, conventional MRI, DW-MRI and histopathologic examinations were done for 42 female patients with abnormal vaginal bleeding. Mean ADC values of endometrial lesions were calculated and compared.Results
Endometrial malignancies showed significant low ADC values (0.82 + 1.09 × 10?3 mm2/s) compared to benign lesions (1.44 + 0.15 × 10?3 mm2/s) (p: 0.000). Using 1.19 × 10?3 mm2/s as cut-off value for distinguishing malignant from benign lesions achieved 88.9% sensitivity and 100% specificity.Conclusion
DW-MRI is useful in distinguishing malignant from benign endometrial lesions and tumor staging as well. 相似文献3.
Mai E.M. Khamis Ayman F. Ahmed Eman I. Ismail Mohamed F. Bayomy Mohammad W. El-Anwar 《The Egyptian Journal of Radiology and Nuclear Medicine》2018,49(2):358-367
Objective
To detect the diagnostic performance of apparent diffusion coefficient (ADC) value and Cho/Cr ratio in distinguishing various pathological subtypes of parotid gland tumors.Patients and Methods
This study included 30 patients (14 males and 16 females; age ranged from 25 to 70?years; mean age 50?±?12.5?years) with 31 parotid gland masses. Diffusion weighted imaging and MR spectroscopy were performed in all patients. ADC values and Cho/Cr ratios were measured for each parotid mass and compared with pathology. The diagnostic performance of ADC value, Cho/Cr ratio, ADC?+?Cho/Cr ratio and ADC?×?Cho/Cr ratio for differentiating pathological subtypes were assessed.Results
Pleomorphic adenomas had highest ADC values and Warthin tumors had highest Cho/Cr ratios. ADC value had the best diagnostic performance in differentiating pleomorphic adenomas from Warthin tumors by using cutoff value 1.12?×?10?3?mm2/sec with sensitivity, specificity, PPV, NPV and accuracy 100% for each. ADC value?×?Cho/Cr ratio had the best diagnostic performance in differentiating malignant from benign tumors, malignant tumors from pleomorphic adenoma and malignant from Warthin’s tumors by using cutoff value 2.37 at which sensitivity, specificity, PPV, NPV and accuracy all were 100%. Conclusion: ADC value and Cho/Cr ratio are useful in differentiating different pathological subtypes of parotid tumors. 相似文献4.
Ghada K. Gouhar Mona A. El-Hariri Wael E. Lotfy 《The Egyptian Journal of Radiology and Nuclear Medicine》2011,42(3-4):451-460
PurposeTo evaluate the correlation of the apparent diffusion coefficient (ADC) using diffusion weighted imaging (DWI) and early/delayed enhancement (E/D) ratio using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) with histological grading in malignant breast lesions.Material and methodsThirty-one women with 34 histopathologically proved malignant breast lesions underwent MRI within 2 weeks prior to surgery. MRI examination included T1 and T2 W sequences, DWI and DCE-MRI. ADC values and E/D ratios are correlated with the histological grades.ResultsThe mean ADC of the malignant lesions was 0.85 ± 0.12 × 10?3 mm2/s. The mean ADC values of grade I, II and III were 0.96 ± 0.12 × 10?3 mm2/s, 0.87 ± 0.07 × 10?3 mm2/s and 0.75 ± 0.12 × 10?3 mm2/s, respectively. Tumours with higher grade showed significantly lower ADC value (p = 0.0001) compared with lower grade and there is an inverse correlation between ADC value and histological grade (r = ?0.62, p-value = 0.0001). The mean E/D ratio for grade I, II and III tumours were 0.98 ± 0.04, 1.01 ± 0.05 and 1.07 ± 0.08, respectively. Tumours with higher grade showed significantly higher E/D ratio (p = 0.005) compared with lower grade and there was a direct correlation between E/D ratio and histological grade (r = 0.44, p = 0.008).ConclusionDWI is a useful diagnostic parameter with significantly higher correlation with the histological grade of breast cancer than DCE MRI, which is an important factor for proper treatment selection. 相似文献
5.
PurposeTo study the diagnostic performance of diffusion weighted MR imaging in differentiation of diabetic osteoarthropathy and osteomyelitis in diabetic foot.Patients and methodsThis prospective study was carried out on 41 patients with diabetic foot, 22 males and 19 females with mean age of 51 years. They underwent diffusion-weighted MR imaging of the foot. The apparent diffusion coefficient (ADC) values of the bony lesions were calculated by two reviewers and correlated with the surgical findings or biopsy. The kappa statistic (k) was used to estimate the proportion of inter-observer agreement of two reviewers.ResultsThe mean ADC of acute diabetic osteoarthropathy was 1.27 ± 0.19 × 10−3 mm2/s for reviewer 1 and 1.26 ± 0.21 × 10−3 mm2/s for reviewer 2. The mean ADC value in diabetic osteomyelitis was 0.86 ± 0.11 × 10−3 mm2/s for reviewer 1 and 0.85 ± 0.12 × 10−3 mm2/s for reviewer 2. There was excellent inter-observer agreement of ADC value of bony lesions in diabetic foot by both reviewers (K = 0.93). There was statistically significant difference in the ADC values of both groups (P = 0.001). The cut-off point of ADC value of both reviewers used in differentiating acute diabetic osteoarthropathy and osteomyelitis were 0.98 × 10−3 mm2/s and 1.04 × 10−3 mm2/s with an accuracy of 94% and 93% and area under the curve of 0.94 and 0.93 respectively.ConclusionWe conclude that the ADC value is a non-invasive imaging parameter that can help in differentiation of diabetic osteoarthropathy from osteomyelitis with excellent inter-observer agreement. 相似文献
6.
Background and purposeThere is no early predictor of treatment response after lung stereotactic body radiotherapy (SBRT). We conducted this pilot study to evaluate whether serial diffusion weighted magnetic resonance imaging (DW-MRI) or positron emission tomography (PET) could predict response after SBRT.Material and methodsEarly stage non-small cell lung cancer patients who received SBRT were eligible. DW-MRI and PET were undertaken pretreatment and every 3 months after SBRT in the first year. Patients with <1 year of follow-up were excluded from the analysis. The apparent diffusion coefficient (ADC) value and maximum standardized uptake value (SUVmax) of tumors were measured and compared between groups with or without local recurrence (LR).ResultsFifteen patients were enrolled and the data of 14 patients were analyzed. The median ADC value was significantly lower in patients with LR (n = 3) than in those without LR (n = 11) at 3 and 6 months (1.11 vs. 1.54 and 0.98 vs. 1.69 [×10−3 mm2/s]; p = 0.039 and 0.012, respectively) while there was no significant difference pretreatment and at 9 and 12 months after treatment. No significant difference was observed in the SUVmax at any time point.ConclusionsDW-MRI could be an early predictor of treatment response after lung SBRT. 相似文献
7.
PurposeTo explore the correlation between intravoxel incoherent motion (IVIM) magnetic resonance (MR) parameters and MR nodular grade of parotid glands in patients with Sjögren’s syndrome (SS).Materials and methodsA total of 31 consecutive patients with SS and 28 gender- and age-matched healthy volunteers underwent bilateral parotid 3.0T MR examination including the IVIM sequence (9 b values, 0–800 s/mm2). The apparent diffusion coefficient (ADC), diffusion coefficient D, pseudo-diffusion coefficient D*, and perfusion fraction f of bilateral parotid glands were obtained, and the nodular grade of each parotid gland was evaluated according to the MR morphological appearance.ResultsSixty-two parotid glands in 31 patients with SS consisted of 32, 14, 8, and 8 parotid glands at MR nodular grades 0, 1, 2, and 3, respectively. In parotid glands of grade 0, 1, 2, 3 and healthy volunteers, the ADC values were (1.13 ± 0.25, 1.11 ± 0.17, 1.05 ± 0.24, 0.89 ± 0.04 and 1.00 ± 0.21) × 10−3 mm2/s, D values were (0.92 ± 0.13, 0.90 ± 0.19, 0.90 ± 0.03, 0.67 ± 0.03, 0.81 ± 0.03) × 10−3 mm2/s, f values were 0.20 ± 0.04, 0.18 ± 0.02, 0.15 ± 0.01, 0.11 ± 0.01, 0.15 ± 0.06, and D*values were (53.89 ± 28.26, 41.78 ± 16.35, 51.24 ± 18.69, 31.83 ± 18.03, 36.83 ± 16.14) × 10−3 mm2/s respectively. The ADC, D, f, and D* values of parotid glands in patients with SS at grade 0 were significantly higher than those in healthy volunteers (all P < 0.05). Significant differences were observed in the D and f values of parotid glands in patients with SS among different grades (P = 0.003, < 0.001, respectively). The IVIM parameters (D, f) of parotid glands at early (grades 0–1) and advanced (grades 2–3) stages in patients with SS were significantly higher and lower, respectively, than those in healthy volunteers (all P < 0.05). The D and f values inversely correlated with MR nodular grades significantly (r = − 0.297, P = 0.019; r = − 0.653, P < 0.001, respectively)ConclusionThe parotid glands with different MR nodular grades in patients with SS showed different IVIM parameters, reflecting different pathophysiological characteristics of parotid glands at different stages. 相似文献
8.
Esam M. Hemat 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(1):115-123
Objective
To assess DWI and ADC value in characterization of orbital masses (differentiation of benign, inflammatory and malignant orbital masses).Patients & methods
Cross-sectional study included 38 patients, and diagnosed histopathologically, clinically and radiologically 26 with benign and inflammatory masses and 12 with malignant masses. Their ages ranged from 15 to 63 years. They were examined using 1.5 T MR machine.Results
There was a significant difference in ADC value of malignant and benign orbital masses. Malignant masses have a lower ADC values and restricted diffusion, compared with benign masses. Using 0.93 × 10?3 mm2/s as a cutoff value, in differentiating malignant from benign lesions, resulted in a total of 80% sensitivity, 83.3% specificity and 82% accuracy. Lesions with ADC values less than 0.87 × 10?3 mm2/s, had 90% likely to be of malignant nature. Lesions with ADC greater than 1.1 × 10?3 mm2/s, had 90% likely to be of benign nature. In between these two values, lesions are indeterminate.Conclusion
Diffusion weighted imaging with ADC value, can help in differentiating malignant from benign orbital masses. Malignant orbital masses have a significant lower ADC value than benign masses. We can use ADC cutoff value between malignant and benign masses. 相似文献9.
Moh Salah Ibrahim Tantawy Mohamed M. Elrakhawy Ahmad El-Morsy Gehad Ahmad Saleh 《The Egyptian Journal of Radiology and Nuclear Medicine》2018,49(3):878-883
Objective
To define the role of diffusion-weighted imaging & apparent diffusion coefficient (ADC) in characterizing complex ovarian masses, with particular concern to differentiating benign versus malignant masses.Materials and methods
We enrolled in this prospective study 30 patients with complex cystic ovarian masses between June 2014 and July 2015. Pelvic MRI and diffusion weighted images at b value of 0, 500, 1000 and 1500?s/mm2 at 1.5?T unit were performed for all patient. The mean ADC values were calculated for both solid & cystic component of the masses. The final diagnoses were confirmed by either pathological examination or culture of aspiration material.Results
Included masses proved benign in 17 (56%) and malignant in 13 (44%). ADC of solid component of malignant showing no statistically significant difference from that of the benign lesions, while ADC values of cystic component in malignant masses were significantly higher than those in benign masses (p?<?0.05). The Receiver operator characteristic (ROC) analysis indicated that a cutoff ADC value of 1.97?×?10?3?mm2/s may be the optimal one for differentiating between benign and malignant masses.Conclusion
The combination of DWI with ADC value measurement and conventional MRI is useful for differentiating benign and malignant ovarian masses. 相似文献10.
PurposeTo describe the diffusion-weighted imaging (DWI) appearance of gestational trophoblastic disease (GTD) and to determine its apparent diffusion coefficient (ADC) values. To evaluate the feasibility of DWI to predict progression of hydatidiform mole (HM) to persistent disease.MethodsDuring a period of 6 months, women with preliminary diagnosis of GTD, based on ultrasound and ßhCG levels, underwent 1.5T MRI (T2 high-resolution and DWI; b values 50, 400, 800; sagittal and perpendicular to the endometrium; and T1, T2 Turbo Spin Echo [TSE] axial images). Patients were followed for 6–12 months to monitor progression to persistent form of the disease. ADC values and image characteristics were compared between HM and persistent neoplasia and between GTD and non-molar pregnancy using Mann–Whitney U and Fisher’s exact tests, respectively.ResultsAmong the 23 studied patients, 19 (83%) were classified as molar and 4 (17%) as non-molar, based on pathology reports. After 6–12 months of follow-up, 5 (26%) cases progressed to persistent disease and 14 (74%) cases were benign HM. There was no significant difference between ADC values for HM (1.93 ± 0.33 × 10−3 mm2/s) and persistent neoplasia (2.03 ± 0.28 × 10−3 mm2/s) (P = 0.69). The ADC of non-molar pregnancies was (0.96 ± 0.46 × 10−3 mm2/s), which was significantly different from GTD (1.96 ± 0.32 × 10−3 mm2/s) (P = 0.001). Heterogeneous snowstorm appearance, focal intratumoral hemorrhage, myometrial contraction, and prominent myometrial vascularity were more common in GTD compared to non-molar pregnancy (P < 0.05).ConclusionHeterogeneous snowstorm appearance, focal intratumoral hemorrhage, myometrial contraction, and prominent myometrial vascularity are among the imaging characteristics of GTD. We cannot use ADC values to predict progression to persistent disease. 相似文献
11.
PurposeThe purpose of the study was to correlate the apparent diffusion coefficient (ADC) values of diffusion-weighted MR imaging (DW-MRI) by 3T device with the histological tumour regression grading (TRG) analysis of colorectal liver metastases after preoperative chemotherapy.Materials and methodsOur study included thirty-five patients with colorectal liver metastases who had undergone MRI by 3T device (GE DISCOVERY MR750; GE Healthcare) after preoperative chemotherapy. DW-MRI was performed using a single-shot spin-echo echo-planar sequence with multiple b-values (0, 150, 500, 1000, 1500 s/mm2), thus obtaining an ADC map. For each liver lesion (more than 1 cm in diameter) the fitted ADC values were calculated by two radiologists in conference and three ROIs were drawn: around the entire tumour (ADCe), at the tumour periphery (ADCp) and at the tumour center (ADCc). All ADC values were correlated with histopathological findings after surgery. Hepatic metastases were pathologically classified into five groups on the basis of TRG. Statistical analysis was performed on a per-lesion basis utilizing the one-way analysis of variance (ANOVA). This retrospective study was approved by our institutional review board; written informed consent was obtained from all patients.ResultsA total of 106 colorectal liver metastases were included for image analysis. TRG1, TRG2, TRG3, TRG4 and TRG5 were observed in 4, 14, 36, 35 and 17 lesions, respectively. ADCe and ADCp values were significantly higher in lesions classified as TRG1 (2.40 ± 0.12 × 10−9 m2/s and 2.28 ± 0.26 × 10−9 m2/s, respectively) and as TRG2 (1.40 ± 0.31 × 10−9 m2/s and 1.44 ± 0.35 × 10−9 m2/s), compared to TRG3 (1.16 ± 0.13 × 10−9 m2/s and 1.01 ± 0.18 × 10−9 m2/s), TRG4 (1.10 ± 0.26 × 10−9 m2/s and 0.97 ± 0.24 × 10−9 m2/s), and TRG5 (0.93 ± 0.17 × 10−9 m2/s and 0.82 ± 0.28 × 10−9 m2/s). ADCe, ADCp and ADCc values were significantly different in TRG classes (p < 0.0001). Statistical correlations were found between the ADCe, ADCp, ADCc values and the TRG classes (Spearman correlation coefficient were −0.568, −0.542 and −0.554, respectively).ConclusionOur study showed a significant correlation between ADC values of 3T DW-MRI and histological TRG of colorectal liver metastases after preoperative chemotherapy. 相似文献
12.
《European journal of radiology》2009,69(3):493-498
ObjectiveTo evaluate whether diffusion-weighted imaging (DWI) is a reliable technique to quantify microstructural differences between head and neck squamous cell carcinomas (SCC) and tumour-free soft tissue.Materials and methodsDWI was obtained from 20 patients with histologically proven, untreated head and neck SCC. DWI was acquired using a diffusion-weighted, navigated echo-planar imaging sequence with a maximum b-value of 800 s/mm2. For an objective assessment of image quality, the signal-to-noise ratio (SNR) was calculated. Microstructural differences between vital tumour tissue and tumour-free soft tissue were quantified by calculating the apparent-diffusion-coefficients (ADC) on a pixel by pixel method.ResultsEcho-planar DWI provided good image quality in all patients (mean SNR 18.4). The mean ADC of SCC, (0.64 ± 0.28 × 10−3 mm2/s), was significantly (P < 0.0001) lower than that of the tumour-free soft tissue, (2.51 ± 0.82 × 10−3 mm2/s).ConclusionDWI is a reliable diagnostic tool to quantify the microstructural differences between vital tumour tissue and tumour-free soft tissue in patients with head and neck SCC. 相似文献
13.
Jehan A. Mazroa Sabry A. Elmogy 《The Egyptian Journal of Radiology and Nuclear Medicine》2011,42(3-4):357-365
The aim of this work was to evaluate the ability of Diffusion MRI using different b values in detection and characterization of liver hemangiomas in order to differentiate them from other focal hepatic lesions.Patients and methodsThirty one hemangiomas in 28 patients were examined with diffusion MR using different four b values: 200, 500, 800 and 1000 s/mm2. Hemangiomas were divided into typical and atypical lesions. Lesions were evaluated regarding size, enhancement pattern, signal intensity and ADC maps in conventional and diffusion MR.ResultsAll hemangiomas showed hyperintense signal at diffusion MR with different b values. In typical and atypical hemangiomas, diffusion MR showed hyperintense signal that persisted with increasing b values. Both types showed hyperintense signal or mixed signals in ADC maps. Mean ADC values (for both types) were 2.47, 2.36, 2.31 and 2.10 × 10?3 mm2/s for b 200, 500, 800 and 1000, respectively. Arterial nodular enhancement pattern of atypical hemangiomas showed significant increased ADC value than other types.ConclusionDWI can successfully detect and characterize hepatic hemangiomas, it provides qualitative and quantitative assessment of hemangiomas. The combination of diffusion signal intensity and ADC maps and values successfully differentiates hemangiomas from other focal lesions rather than signal intensity changes in different b values. 相似文献
14.
Can Zafer Karaman Ahmet Tanyeri Recep
zgür Veli Süha
ztürk 《Dento maxillo facial radiology》2021,50(4)
Objectives:The aim of this study was to investigate the relationship between pathological classification of parotid gland tumors and conventional MRI – diffusion-weighted imaging findings and also contribute the possible effect of apparent diffusion coefficient (ADC) to diagnosis.Methods:60 patients with parotid masses diagnosed using histopathology and/or cytology were enrolled in this retrospective study. All patients were evaluated using a 1.5 T MRI. Demographic features, conventional MRI findings, and ADC values (mean, minimum, maximum, and relative) were recorded. MRI findings and ADC values were compared between benign–malignant groups and pleomorphic adenoma vs Warthin’s tumor groups.Results:60 tumors (48 benign, 12 malignant) were evaluated in a total of 60 patients (39 males, 21 females). The mean age was 59 (±14, 18–86) years old; the mean lesion size was 26 (±10, 11–61) mm. On the texture of conventional MRI, T2 dominantly hyperintense/with hypointensity signal was seen in 87% of pleomorphic adenomas and T2 dominantly hypointense/with hyperintesity signal was encountered in 64% of all Warthin’s tumors. Seven (28%) Warthin’s tumors were misdiagnosed as pleomorphic adenomas and two others (8%) as malignant tumors. The commonly used mean ADC value was 1.6 ± 0.6 × 10–3 mm2 s−1 for benign tumors, 0.8 ± 0.3 × 10–3 mm2 s−1 for malign tumors, 1 (0.9–1.8) × 10–3 mm2 s−1 for Warthin’s tumors, and 1.9 ± 0.3 × 10–3 mm2 s−1 for pleomorphic adenomas. There was a statistically significant difference in ADC values between benign-malignant tumors and pleomorphic adenomas-Warthin’s tumors.Conclusions:Warthin’s tumor may occasionally be misdiagnosed as pleomorphic adenoma and malignant tumor because of variable morphologic features. In addition to benign–malignant differentiation, the added ADC measurement may also be useful for differentiating Warthin’s tumors from pleomorphic adenomas. 相似文献
15.
ObjectivesTo compare Apparent Diffusion Coefficient (ADC) measurements in rectal neoplastic lesions before and after lumen distension obtained with sonography transmission gel.MethodsFrom January 2014 to July 2016, 25 patients (average age 63.7, range 41–85, 18 males) were studied for pre-treatment rectal cancer staging using a 1.5 T MRI. Diffusion MRI was obtained using echo-planar imaging with b = 800 value; all patients were studied acquiring diffusion sequences with and without rectal lumen distension obtained using sonography transmission gel. In both diffusion sequences, two blinded readers calculated border ADC values and small ADC values, drawing regions of interest respectively along tumour borders and far from tumour borders. Mean ADC values among readers − for each type of ADC measurement − were compared using Wilcoxon matched pairs signed rank test. Correlation was assessed using Pearson analysis.ResultsBorder ADC mean value for diffusion MR sequences without endorectal contrast was 1.122 mm2/sec, with 95% Confidence Interval (CI) = 1.02–1.22; using gel lumen distension, higher border ADC mean value of 1.269 mm2/s (95% CI = 1.16–1.38) was obtained. Wilcoxon matched pairs signed rank test revealed statistical difference (p < 0.01); a strong Pearson correlation was reported, with r value of 0.69. Small-ADC mean value was 1.038 mm2/s (95% CI = 0.91–1.16) for diffusion sequences acquired without endorectal distension and 1.127 mm2/s (95% CI = 0.98–1.27) for diffusion sequences obtained after endorectal gel lumen distension. Wilcoxon analysis did not show statistical difference (p = 0.13). A very strong positive correlation was observed, with r value of 0.81.ConclusionsADC measurements are slightly higher using endorectal sonographic transmission gel; ROI should be traced far from tumour borders, to minimize gel filled-pixel along the interface between lumen and lesion. Further studies are needed to investigate better reliability of ADC in rectal cancer MRI using sonographic gel intraluminal distension. 相似文献
16.
Hatice Tuba Sanal Sedat Yilmaz Ismail Simsek Muhammet Cinar Hakan Erdem Salih Pay Ayhan Dinc Cem Tayfun 《Clinical imaging》2013,37(4):734-739
AimTo compare apparent diffusion coefficients (ADCs) of sacroiliac joints (SIJs) in ankylosing spondylitis (AS) patients during advanced-active and advanced-nonactive stages.Materials–MethodsAS patients with chronic-active (n= 19), chronic-nonactive (n= 6), and controls with normal SIJs (n= 8) were included. Mean ADCs through 43 subchondral bone marrow edema lesions (SBMELs) were calculated.ResultsMean ADCs were 1.60 +/? 0.32×10–3 mm2/s over SBMELs, 0.57 +/? 0.23×10–3 mm2/s at periphery of SBMELs, 0.57 +/? 0.24×10–3 mm2/s in chronic-nonactive group, and 0.61 +/? 0.19×10–3 mm2/s for controls.ConclusionADCs lower than 0.69×10–3 mm2/s, obtained at subchondral aspect of SIJs of established AS patients with chronic changes, which this number represents the receiver operating characteristic (ROC) best cutoff value, can be considered as normal without possible residual inflammation of concern. 相似文献
17.
Ali H. Elmokadem Ahmed M. Abdel Khalek Rihame M. Abdel Wahab Nehal Tharwat Ghada M. Gaballa Mohamed Abo Elata Talal Amer 《Journal l'Association canadienne des radiologistes》2019,70(3):264-272
PurposeThis study was designed to evaluate the role of multiparametric magnetic resonance imaging (MRI) for differentiation of parotid gland neoplasms.MethodsProspective study was conducted upon 52 consecutive patients (30 men, 22 women; aged 24–78 years; mean, 51 years) with parotid tumours that underwent multiparametric MRI using combined static MRI, dynamic contrast enhanced (DCE) MRI, and diffusion-weighted imaging (DWI). The static MRI parameter, time signal intensity curves (TIC) derived from DCE-MRI, and apparent diffusion coefficient (ADC) values of parotid tumours were correlated with histopathological findings.ResultsStatic MRI revealed a significant difference between both benign and malignant lesions in regards to margin definition (P < .001) and T2 hypointensity (P < .013), with a diagnostic accuracy 95% and 78.33% respectively. Study of the TIC type on DCE-MRI revealed statistically significant difference between benign and malignant lesions (P < .001) and diagnostic accuracy 96.55%. There was no statistically significant difference (P = .181) between the ADC values of benign and malignant lesions. ROC curve analysis revealed that by using ADC cut-off value of 1 × 10?3 mm2/s had accuracy of 84.62% respectively for differentiating Warthin from malignant tumours that could be modified to higher value (94.28%) by excluding lymphoma from malignant lesions. By using cutoff value of 1.3 × 10?3 mm2/s to differentiate pleomorphic adenoma from malignancy, ROC curve analysis had high accuracy of 97.06%.ConclusionMultiparametric MRI can be used for differentiation of malignant from benign parotid tumours and characterization of some benign parotid tumours. 相似文献
18.
《European journal of radiology》2014,83(12):2122-2128
ObjectiveThe purpose of this study was to evaluate the correlations between histological differentiation and Lauren classification of gastric cancer and the apparent diffusion coefficient (ADC) value of diffusion weighted imaging (DWI).Materials and methodsSixty-nine patients with gastric cancer lesions underwent preoperative magnetic resonance imaging (MRI) (3.0T) and surgical resection. DWI was obtained with a single-shot, echo-planar imaging sequence in the axial plane (b values: 0 and 1000 s/mm2). Mean and minimum ADC values were obtained for each gastric cancer and normal gastric walls by two radiologists, who were blinded to the histological findings. Histological type, degree of differentiation and Lauren classification of each resected specimen were determined by one pathologist. Mean and minimum ADC values of gastric cancers with different histological types, degrees of differentiation and Lauren classifications were compared. Correlations between ADC values and histological differentiation and Lauren classification were analyzed.ResultsThe mean and minimum ADC values of gastric cancers, as a whole and separately, were significantly lower than those of normal gastric walls (all p values <0.001). There were significant differences in the mean and minimum ADC values among gastric cancers with different histological types, degrees of differentiation and Lauren classifications (p < 0.05). Mean and minimum ADC values correlated significantly (all p < 0.001) with histological differentiation (r = 0.564, 0.578) and Lauren classification (r = −0.493, −0.481).ConclusionsThe ADC values may be helpful as a noninvasive tool for evaluating the histological features of gastric cancer, such as histological type, degree of differentiation and Lauren classification. 相似文献
19.
ObjectiveTo assess the feasibility of computed diffusion-weighted imaging (cDWI) in comparison with directly acquired DWI for visualizing pancreatic adenocarcinomas.Materials and methodsPatients with pancreatic adenocarcinoma underwent DWI at b-values of 0, 1000 (DWI1000), 1500 (DWI1500) and 2000 (DWI2000) s/mm2. From DWIs at b-values of 0 and 1000 s/mm2, we generated cDWIs at b-values of 1500 (cDWI1500) and 2000 (cDWI2000) s/mm2. DWI findings of pancreatic adenocarcinomas (clear hyperintensity; hyperintensity with an unclear distal border; and isointensity), the image quality and the tumor to pancreas contrast ratio (CR) were compared between directly acquired DWI and cDWI.ResultsAmong the 63 included patients, clear hyperintense tumors were seen in 35 on DWI1000, 50 on DWI1500, 50 on cDWI1500, 53 on DWI2000 and 44 on cDWI2000. Incidence of clear hyperintense tumors was significantly higher on cDWI1500 than on DWI1000 (P = 0.013). There was no significant difference in the incidence of clear hyperintense tumors between DWI1500 and cDWI1500 (P > 0.999), but a lower incidence was seen on cDWI2000 than on DWI2000 (P = 0.028). Image quality was lower on cDWI than on DWI at b-values of 1500 (P = 0.002) and 2000 s/mm2 (P < 0.001). The tumor to distal pancreas CR was significantly higher on cDWI2000 than on cDWI1500 (P < 0.001), and on cDWI1500 than on DWI1000 (P < 0.001). The cDWI showed a significantly higher tumor to distal pancreas CR than DWI at b-values of 1500 (P = 0.004) and 2000 s/mm2 (P < 0.001).ConclusionscDWI1500 generated from b-values of 0 and 1000 s/mm2 should be considered more effective than DWI1000 and at least as effective as DWI1500. 相似文献
20.
Moustafa Abdel Kader Hosny Sayed Abdel Ghani Zienab Moustafa Saad Nilly Helmy Abdalla Eman Abdel Razek 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(4):825-837