共查询到20条相似文献,搜索用时 46 毫秒
1.
Reem Hassan Bassiouny Tarek YoussefOlaa Hassan 《The Egyptian Journal of Radiology and Nuclear Medicine》2012
Objective
The purpose of our study was to investigate whether adding diffusion weighted imaging to dynamic contrast-enhanced MRI could improve the diagnostic performance of breast MRI.Materials and methods
This retrospective study included 86 women with 93 primary and postoperative breast lesions detected on DCE-MRI who underwent subsequent biopsy. The diagnostic performance was calculated for DCE-MRI alone, combined DCE-MRI and quantitative DWI, and for quantitative DWI alone.Results
Of the 93 lesions, 42 were benign and 51 malignant (5 DCIS, 41 IDC, 2 ILC, 3 NOS). Both DCIS (mean ADC = 1.17 ± 0.12 × 10−3 mm2/s) and IDC (mean ADC, 0.98 ± 0.14) exhibited lower mean ADC values than benign lesions (ADC value = 1.72 ± 0.36). Applying an ADC cutoff value of 1.33 increased the specificity and PPV of DCE-breast MRI from 59.5% and 75% to 78.5% and 83.3%, respectively. The specificity and PPV for quantitative DW-MRI alone (73.5% and 83.3%) were close to those broken out from the combined use of DCE and quantitative DW-MRI. However, the sensitivity and NPV of DWI remains lower than that of DCE-MRI.Conclusion
DWI shows potential for improving the diagnostic performance of breast MRI and may reduce the number of unnecessary biopsies. 相似文献2.
Sally Emad-Eldin Manal Halim Lamiaa I.A. Metwally Rania Mahmoud Abdel-Aziz 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Purpose
Our aim was to investigate the diffusion-weighted Imaging (DWI) appearance and apparent diffusion coefficient (ADC) values of normal prostatic gland, prostate carcinoma (PCa) and benign prostate hyperplasia (BPH) and to determine the utility of DWI in their characterization.Materials and methods
During a period of 16 months, 40 consecutive patients, with elevated PSA level and 12 healthy volunteers with no clinical symptoms or history of prostate disease were prospectively evaluated with DWI of the prostate. MRI was performed using a 1.5T MR scanner equipped with a pelvic phased array coil. For anatomical imaging, T2W FSE in the three orthogonal planes, and T1WI in axial plane were obtained. DWI with b values of 0, 300, 500 and 800 s/mm2 were performed in axial plane. The results were confirmed by TRUS-guided biopsy or prostatectomy.Results
Patients ranged in age from 45 to 85 years (mean 66.6 ± 7.9 year). Twenty patients were confirmed to have BPH, whereas 20 patients had PCa. The mean and SD of ADC values for the peripheral zone (PZ), central gland (CG), BPH nodules and PCa were 1.839 ± 0.233, 1.469 ± 0.239, 1.359 ± 0.201 and 0.87 ± 0.13 respectively. The mean ADC value of PCa was significantly lower than that of CG, PZ, and BPH nodule, with p value <0.05.Conclusion
DW MR imaging characteristics and ADC values can differentiate PCa and BPH. DWI with ADC may be used as a complementary method to conventional MRI in diagnosis of PCa and BPH. 相似文献3.
Xingchen Wu Hannu Pertovaara Prasun Dastidar Martine Vornanen Lassi Paavolainen Varpu Marjomäki Ritva Järvenpää Hannu Eskola Pirkko-Liisa Kellokumpu-Lehtinen 《European journal of radiology》2013
Purpose
Diffusion-weighted magnetic resonance imaging (DW-MRI) allows quantifying the random motion of water molecules in tissue by means of apparent diffusion coefficient (ADC) measurements. The aim of the study was to determine whether ADC measurements allow discrimination of diffuse large B-cell lymphoma (DLBCL) from follicular lymphoma (FL), and to examine the relationship between cellularity and ADC value of the tumor using DWI.Materials and methods
Thirty-two patients with histologically proven non-Hodgkin lymphoma (21 with DLBCL and 11 with FL, 17 males and 15 females, mean age 62 ± 13 years) underwent conventional MRI and DWI examination before treatment. The ADC values of DLBCL were compared to those of FL. The ADC value of the tumor was also correlated with the tumor tissue cellularity.Results
The mean ADC value of DLBCL was not significantly different from that of FL (0.70 ± 0.16 × 10−3 mm2/s vs. 0.76 ± 0.12 × 10−3 mm2/s, P = 0.21). The cellularity of DLBCL was significantly lower than that of FL (2991 ± 351 cells/view vs. 4412 ± 767 cells/view, P < 0.001). There was no correlation between the ADC value and the tissue cellularity of the tumor in patients with DLBCL and FL.Conclusion
ADC measurements could not differentiate between DLBCL and FL, and there was no correlation between the ADC value and cellularity of the tumor in patients with DLBCL and FL. 相似文献4.
Irene Bargellini Elena Bozzi Daniela Campani Paola Carrai Paolo De Simone Luca Pollina Roberto Cioni Franco Filipponi Carlo Bartolozzi 《European journal of radiology》2013
Purpose
To retrospectively evaluate agreement between modified RECIST (mRECIST) assessed at Computed Tomography (CT) and pathology in a large series of patients with hepatocellular carcinoma (HCC) who were transplanted after transarterial chemoembolization (TACE).Materials and methods
IRB approval was obtained. The study included 178 patients (M/F = 155/23; mean age 55.8 ± 6.3 years) with HCC who were transplanted after TACE from January 1996 to December 2010 and with at least one CT examination before liver transplantation (LT). Two blinded independent readers retrospectively reviewed CT examinations, to assess tumor response to TACE according to mRECIST. Patients were classified in responders (complete and partial response) and non-responders (stable and progressive disease). On the explanted livers, percentage of tumor necrosis was classified as 100, >50 and <50%.Results
The mean interval between latest CT and LT was 57.4 ± 39.8 days. At latest CT examination, the objective response rate was 78.1% (139/178), with 86 cases (48.3%) of complete response (CR). A good intra- (k = 0.75 and 0.86) and inter-observer (k = 0.81) agreement was obtained. On a per-patient basis, agreement between mRECIST and pathology was obtained in 120 patients (67.4%), with 19 cases (10.7%) of underestimation and 39 cases (21.9%) of overestimation of tumor response at CT. CT sensitivity and specificity in differentiating between responders and non-responders were 93 and 82.9%, respectively. Out of 302 nodules, sensitivity and specificity of CT in detecting complete necrosis were 87.5 and 68.9%, respectively.Conclusions
CT can overestimate tumor response after TACE. Nonetheless, mRECIST assessed at CT after TACE are reproducible and reliable in differentiating responders and non-responders. 相似文献5.
Reham M. Osama Ahmed H.K. Abdelmaksoud Sanaa A.M. El Tatawy Mohammed M. Nabeel Lamia I.A. Metwally 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Purpose
The purpose of this study is to evaluate the role of dynamic contrast enhanced and diffusion weighted MRI in the assessment of response and necrosis in the treatment of hepatocelluar carcinoma after transcatheter arterial chemoembolization (TACE).Subjects and methods
Precontrast T1, T2, STIR, Dynamic contrast enhanced and respiratory triggered diffusion weighted MR images (b factor, 500, 1000 s/mm2 obtained in 50 patients with hepatocellular carcinoma who underwent transarterial hepatic chemoembolization). Diffusion-weighted MR images, gadolinium-enhanced MR images after TACE were assigned confidence levels for postoperative HCC recurrence. The sensitivity, specificity, PPV, NPV and overall agreement were calculated for both the dynamic and the DWI images. Apparent diffusion coefficients (ADCs) were calculated searching for a cut off value using the ROC curve.Results
Dynamic MRI had a sensitivity of 90.5%, a specificity of 96.6%, a positive predictive value of 95%, a negative predictive value of 93.3% and an overall agreement of 94% compared to 100%, 65.5%, 67.7%, 100% and 80% respectively of diffusion weighted imaging.The difference between the malignant and benign groups’ ADC variables was statistically significant P value 0.006.The ROC curve showed that the area under the curve is C = 0.728 with SE = 0.075 and 95% CI from 0.582 to 0.874.Conclusion
Diffusion weighted MR imaging has lower specificity compared to dynamic MRI with increased false positives. We suggest that increase is due to intralesional hemorrhage or liquefactive necrosis causing diffusion restriction. Diffusion weighted imaging may act as a supplementary sequence to compensate the dynamic MRI in patients who could not hold their breath adequately. 相似文献6.
Haitham A. Dawood Tamir A. HassanNesreen Mohey 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Purpose
To evaluate the role of real-time sonoelastography (UE) and apparent diffusion coefficient (ADC) value measurement in differentiating benign versus malignant enlarged neck lymph nodes.Materials and methods
This study included 26 patients presented with 32 enlarged neck lymph nodes (LNs), underwent real-time UE and diffusion weighted MRI (DWI). ADC maps are generated from DWI and ADC values were calculated. Both UE and ADC findings were compared with histopathological results.Results
The LNs were 12 benign lymphadenopathy (37.5%, seen in 10 patients), 10 metastatic (31.25% seen in 8 patients) and 10 lymphoma (31.25%, seen in 8 patients) including 4 LNs with Hodgkin’s lymphoma (HL, seen in 3 patients) and 6 LNs with non Hodgkin’s lymphoma (NHL, seen in 5 patients). On UE 10 of the 12 benign LNs had pattern of 1–2 (83.3%) and 18 of 20 neoplastic LNs (90%) had pattern of 4–5. The mean ADC values of the benign, metastases and lymphoma groups were 1.52 ± 0.37, 0.90 ± 0.15 and 0.72 ± 0.12 × 10−3 (mm2/s), respectively.Conclusion
Combined real-time UE and ADC value measurement are non invasive techniques useful for differentiation of enlarged neck lymph. The combination potentially could reduce unnecessary biopsy especially for elasticity pattern 1–2. 相似文献7.
Anup Gupta Shailesh M. Prabhu Jyoti Sureka Geeta Chacko 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Purpose
Atypical and malignant meningiomas are considered to have a higher rate of recurrence and show aggressive behavior compared to benign variety. The purpose of our study was to study the role of diffusion weighted imaging and determination of apparent diffusion coefficient (ADC) values and ADC ratios to differentiate typical meningiomas from atypical/malignant variety at 1.5 and 3T MRI.Materials and methods
A total of 94 adult patients (48 patients at 3T and 46 patients at 1.5T) with pathologically proven meningiomas were retrospectively evaluated on conventional and diffusion weighted MRI. The signal intensity of the lesions on DW imaging was evaluated. ADC values and ADC ratios were calculated from lesion and contralateral normal white matter.Results
94 lesions comprising of 66 benign and 28 atypical meningiomas were evaluated. The mean ADC values at 3T MRI were 0.82 ± 0.12 × 10−3 in benign (typical) meningiomas and 0.68 ± 0.10 × 10−3 in atypical meningiomas. At 1.5T, the mean ADC values of benign meningiomas were 0.83 ± 0.11 × 10−3 and 0.70 ± 0.09 × 10−3 in atypical meningiomas. The mean ADC ratios were 1.08 ± 0.17 and 0.85 ± 0.15 for benign and atypical meningiomas respectively. There was a statistically significant difference between the mean ADC ratios and the mean ADC values of typical and atypical meningiomas (P < 0.001) at both 1.5T and 3T MRI.Conclusion
DWI with calculation of apparent diffusion coefficient (ADC) values and ADC ratios has a potential role in differentiating benign from atypical meningiomas at both 1.5 and 3T MRI. The differences in mean ADC values between benign and atypical meningiomas were similar at both 1.5 and 3T MRI. 相似文献8.
Eman Nasr Ikram Hamed Iman Abbas Nagat M. Khalifa 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Introduction
Ovarian tumors; are the second most common gynecological tumor and are the fifth commonest tumor in women. It is desirable to preoperatively differentiate benign from malignant tumor to decide whether surgery is required, and which type of surgery is appropriate avoiding unnecessary surgery, adding dynamic contrast and diffusion weighted to conventional images can help in differentiation of benign ovarian tumor from malignant. DWI depends on the fact that water molecules can diffuse freely in low cellular environment, while tissue hyper cellularity causes its restriction. As a result, malignant ovarian tumors due to its hypercellular nature show restriction of diffusion, unlike most benign tumors. This study aims at reviewing and emphasizing the role of dynamic contrast enhanced MRI and diffusion-weighted MR in characterization of ovarian lesions.Patients and methods
This study was performed on 30 patients referred to the radiology department from surgical department by ovarian masses. Pelvic MR with DWI was done for all patients, DCE-MR was done for 29 out of 30 patients. Twenty-five patients underwent surgery with pathologic correlation. Five patients were put under regular follow up US for 3 months.Results
The sensitivity of MRI was 99.9% while that of DWI was 100%. The specificity was higher for DWI (75%) compared to conventional MRI (58.3%), as well as the accuracy which was 73.9% for MRI while that of DWI was 86.9%. The mean ADC values for malignant lesions were (0.84 × 10−3 ± 0.1 SD mm2/s), while that for benign lesions were (1.8 × 10−3 ± 0.5 SD mm2/s), with cut off 1.2 × 10−3 and p value = 0.005. Mature teratomas showed restricted diffusion with ADC values 0.8 × 10−3 mm2/s (false positive), due to mixed cellularity of the teratoma. Hemorrhagic cysts and endometriomas showed high signal not only on diffusion images but also on corresponding ADC map and ADC values 1.3–1.4 × 10−3 (T2 Shine-through). Sensitivity of MRI was 99.9% while that of DCE-MRI was 60%. The specificity was higher for DCE 91% compared to conventional MRI sequences 58.3%, as well as the accuracy which was 73.9% for MRI while that of DCE was 77% and so addition of DCE to the MRI is expected to increase the specificity and the accuracy of examination.Conclusion
Combination of DWI and DCE to conventional MRI improves the specificity of MRI and thus increasing radiologist’s confidence in image interpretation which will finally reflect on patients’ outcome and prognosis. 相似文献9.
Role of diffusion-weighted imaging with ADC mapping and in vivo H-MR spectroscopy in thyroid nodules
Mona A. El-Hariri Ghada K. Gouhar Nagwa S. Said Mohamed M. Riad 《The Egyptian Journal of Radiology and Nuclear Medicine》2012
Purpose
To evaluate the role of the combined techniques of apparent diffusion coefficient (ADC) generated from diffusion-weighted magnetic resonance (MR) imaging (DWI) and metabolite spectrum acquired by magnetic resonance spectroscopy (MRS) in differentiating benign from malignant thyroid nodules.Materials and methods
Thirty-seven patients with 56 thyroid nodules were evaluated with conventional MRI (T1- & T2-WI), DWI (b value 0.500 s/mm2; ADC values were calculated for the thyroid nodules), and MRS (for the presence or absence of choline peak). The ADC values and MRS findings were correlated with the histopathological results.Results
The mean ADC of the malignant thyroid nodules (0.89 ± 0.27 × 10−3 mm2/s) was significantly lower than that of the mean ADC of the benign thyroid nodules (1.85 ± 0.24 × 10−3 mm2/s) (p value <0.0001). ADC value of 1.5 × 10−3 mm2/s was used as a cut-off value for differentiation benign from malignant thyroid nodules. The sensitivity, specificity, PPV&NPV of DWI in differentiating benign from malignant thyroid nodules were 94%, 95%, 94% & 95%, respectively (Kappa test 0.84, p value <0.0001), whereas they were 94.7%, 89.2%, 81.8% & 97.1% (Kappa test 0.8, p value <0.0001) with MRS, and 96%, 100%, 100% & 97% (Kappa test 0.96, p value <0.0001) with both DWI and MRS.Conclusion
Both DWI and MRS are useful diagnostic modalities for characterization and differentiation between benign and malignant thyroid nodules. Our preliminary results showed that combination of DWI with calculated ADC values and metabolite spectrum acquired by MRS add more information to MRI and should be considered as an additional and complementary tool to conventional MRI for differentiating benign from malignant thyroid nodules. 相似文献10.
Soo Yeon Hahn Eun Young Ko Boo-Kyung Han Jung Hee Shin Eun Sook Ko 《European journal of radiology》2014
Objective
To investigate whether the addition of diffusion-weighted imaging (DWI) to dynamic contrast-enhanced MRI (DCE-MRI) improves diagnostic performance in predicting pathologic response and residual breast cancer size following neoadjuvant chemotherapy.Materials and methods
A total of 78 consecutive patients who underwent preoperative breast MRI with DWI following neoadjuvant chemotherapy were enrolled. DWI was performed on a 1.5 T system with b values of 0 and 750 s/mm. or on a 3 T system with b values of 0 and 800 or 0 and 1000 s/mm. The images on DCE-MRI alone, DWI alone, and DCE-MRI plus DWI were retrospectively reviewed. We evaluated the diagnostic performances of the three MRI protocols for the detection of residual cancer. The tumor size as predicted by MRI was compared with histopathologic findings. Apparent diffusion coefficient (ADC) values were also compared between the groups with and without residual cancer.Results
Of the 78 patients, 59 (75.6%) had residual cancer. For detection of residual cancer, DCE-MRI plus DWI had higher specificity (80.0%), accuracy (91.0%), and PPV (93.2%) than DCE-MRI or DWI alone (P = 0.004, P = 0.007, and P = 0.034, respectively). The ICC values for residual cancer size between MRI and histopathology were 0.891 for DCE-MRI plus DWI, 0.792 for DCE-MRI, and 0.773 for DWI. ADC values showed no significant differences between residual cancer and chemotherapeutic changes (P = 0.130).Conclusions
The addition of DWI to DCE-MRI significantly improved diagnostic performance in predicting pathologic response and residual breast cancer size after neoadjuvant chemotherapy. 相似文献11.
Enida Bufi Paolo Belli Marialuisa Di Matteo Daniela Terribile Gianluca Franceschini Luigia Nardone Gianluigi Petrone Lorenzo Bonomo 《European journal of radiology》2014
Aim
The estimation of response to neoadjuvant chemotherapy (NAC) is useful in the surgical decision in breast cancer. We addressed the diagnostic reliability of conventional MRI, of diffusion weighted imaging (DWI) and of a merged criterion coupling morphological MRI and DWI. Diagnostic performance was analysed separately in different tumor subtypes, including HER2+ (human epidermal growth factor receptor 2)/HR+ (hormone receptor) (hybrid phenotype).Materials and methods
Two-hundred and twenty-five patients underwent MRI before and after NAC. The response to treatment was defined according to the RECIST classification and the evaluation of DWI with apparent diffusion coefficient (ADC). The complete pathological response – pCR was assessed (Mandard classification).Results
Tumor phenotypes were Luminal (63.6%), Triple Negative (16.4%), HER2+ (7.6%) or Hybrid (12.4%). After NAC, pCR was observed in 17.3% of cases. Average ADC was statistically higher after NAC (p < 0.001) among patients showing pCR vs. those who had not pCR. The RECIST classification showed adequate performance in predicting the pCR in Triple Negative (area under the receiver operating characteristic curve, ROC AUC = 0.9) and in the HER2+ subgroup (AUC = 0.826). Lower performance was found in the Luminal and Hybrid subgroups (AUC 0.693 and 0.611, respectively), where the ADC criterion yielded an improved performance (AUC = 0.787 and 0.722). The coupling of morphological and DWI criteria yielded maximally improved performance in the Luminal and Hybrid subgroups (AUC = 0.797 and 0.761).Conclusion
The diagnostic reliability of MRI in predicting the pCR to NAC depends on the tumor phenotype, particularly in the Luminal and Hybrid subgroups. In these cases, the coupling of morphological MRI evaluation and DWI assessment may facilitate the diagnosis. 相似文献12.
Guoxing Zhou Xiao Chen Jianhua Zhang Jingqi Zhu Genlin Zong Zhongqiu Wang 《European journal of radiology》2014
Background
Diffusion weighted magnetic resonance imaging (DWI) and dynamic contrast-enhanced (DCE) MRI have been considered useful for pathological staging and histological grading in bladder cancer. To our knowledge, no study has combined the two imaging modalities together to assess aggressiveness of bladder cancer.Objective
To assess the clinical aggressiveness of bladder cancer with DCE MRI and DWI at 3.0 T.Materials and methods
A total of 59 patients with 69 pathologically confirmed tumor lesions were included in this study. All patients underwent MR examination at 3.0 T basing on DWI and DCE imaging. Tumor staging and histological grade were evaluated. The aggressiveness of bladder cancer was classified as low-, intermediate-, or high-aggressiveness according to its pathological phenotype. Apparent diffusion coefficient (ADC) value and semi-quantitative parameters (wash-in rate and wash-out rate) were determined. The correlation between clinical aggressiveness and ADC value, wash-in rate and wash-out rate were analyzed. In addition, the diagnostic accuracy of the diffusion and semi-quantitative parameters were estimated using receiver operating characteristic curve (ROC).Results
Aggressiveness of bladder cancer is negatively correlated with ADC value (r = −0.705, p < 0.0001) and wash-out rate (r = −0.719, p < 0.0001). The tumor ADC value is positively correlated with wash-out rate (r = 0.555, p < 0.0001). The diagnostic specificity and accuracy using tumor ADC value and wash-out for the tumor with size <24 mm were better than that tumors with size ≥24 mm. The sensitivity, specificity and accuracy of ADC and wash-out rate in combination in diagnosis of bladder cancer aggressiveness were 96.7%, 94.9% and 95.7%, respectively. ROC curve revealed the diagnostic performance of aggressiveness of bladder cancer using ADC value and wash-out rate were 0.928 (cut-off value: 0.905 × 10−3 mm2/s) and 0.891 (cut-off value: 0.685 min−1), respectively.Conclusion
ADC and wash-out rate derived from DWI and DCE-MRI at 3.0 T have good potential to assess the aggressiveness of bladder cancer and the accuracy was greater for ADC than for semi-quantitative parameters. 相似文献13.
Mohamed I. Yousef Medhat M. Refaat Mohamed H. Faheem 《The Egyptian Journal of Radiology and Nuclear Medicine》2017,48(4):817-824
Aim
To evaluate accuracy of DWI in evaluating HCC response to DEB TACE and compare the results with DCE MRI.Material and methods
42 patients with 59 lesions underwent precontrast abdominal MRI, DWI, ADC map with ADC value measurement and DCE MRI. The qualitative DWI and ADC values were correlated to the DCE MR findings.Results
Comparing the qualitative DWI findings to DCE MRI, showed sensitivity of 83.9%, specificity of 64.3%, positive predictive value of 72.2%, and negative predictive value of 78.3% and overall accuracy of 74.5%. The measured ADC values showed significant difference (P value <0.05) between the ADC values measured in the active tumoral areas and necrotic areas with no significant difference between areas of active tumoral enhancement in the different groups. ROC analysis for ADC values showed area under curve 0.7 and maximum combined sensitivity and specificity of 79% and 69.6% respectively at cutoff ADC value of 1.395?mm2/sec.Conclusion
DWI is useful highly sensitive technique in evaluation of HCC response to DEB TACE, yet it has low specificity related to high number of false positive results preventing using it solely. Also, DWIs is a reliable method in differentiation between active tumor residue/recurrence and benign perilesional enhancement. 相似文献14.
Faten Fawzy Mohamed Ahmed A. Azeem Ismail Doaa Ibrahim Hasan Waleed Elhady Essa 《The Egyptian Journal of Radiology and Nuclear Medicine》2013
Background
Diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) map provide information on MRI about the cellularity of the tumor and have an important role in the pre-operative differentiation of different tumor types.Aim
Is to evaluate the role of ADC value measurement in the differentiation between the most common pediatric posterior fossa tumors which include juvenile pilocytic astrocytoma, ependymoma and medulloblastoma.Patients & methods
Thirty patients were retrospectively included in this study. They were referred from the Neurosurgery Department and all of them suspected to have posterior fossa SOL according to the contrast enhanced CT. All patients were subjected to conventional MRI followed by diffusion MR imaging and calculation of the ADC values.Results
In JPA (group 1, n = 14), ADC values ranged between 2.4 and 1.3 × 10−3 mm2/s, ependymoma (group 2, n = 9), ADC values ranged between 1 and 1.3 × 10−3 mm2/s and medulloblastoma (group 3, n = 7), ADC values ranged between 0.5 and 0.9 × 10−3 mm2/s. Statistically significant difference in ADC value was detected between group1, group 2 and group 3, while no statistically significant difference was detected between group 1 and group 2.Conclusion
The calculation of ADC value in the solid enhancing portion of a tumor is a simple and reliable technique for preoperative differentiation of the most common posterior fossa. 相似文献15.
Klaus M. Friedrich Wolfgang Matzek Stephan Gentzsch Irene Sulzbacher Christian Czerny Andreas M. Herneth 《European journal of radiology》2008
Objective
To 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 methods
DWI 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.Results
Echo-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).Conclusion
DWI 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16.
Background
Diffusion-weighted MRI (DW-MRI) shows the early changes in microscopical movement of water molecules, hence diagnosis of early sacroiliitis which is one of the diagnostic criteria of seronegative spondyloarthropathies.Objective
To determine the value of DW-MRI in detection of signal characteristics of the sacroiliac joints in patients with early ankylosing spondylitis (AS).Patients and methods
Fifteen patients with clinically suspected AS, 20 patients with mechanical low back pain and 20 healthy controls underwent conventional MRI and DWI. Apparent diffusion coefficient (ADC) was measured. In addition ten clinically confirmed AS patients underwent whole body-DWI.Results
Mean ADC values of both sacroiliac joints in AS patients were (0.523 ± 0.15) × 10−3 mm2/s in the ilium and (0.502 ± 0.15) × 10−3 mm2/s in the sacrum. There was no significant difference between mechanical LBP and healthy controls. But there was a significant difference between AS and LBP patients. Mean ADC value of focal lesions of clinically confirmed AS was 0.965 ± 0.25 × 10−3 mm2/s in the sacrum and 0.932 ± 0.31 × 10−3 mm2/s in the ilium.Conclusion
Subchondral bone marrow ADC values of sacroiliac joints allow differentiation between inflammatory and mechanical LBP. Furthermore, it may be helpful in evaluating the efficacy of the treatment and determine disease prognosis. 相似文献17.
Jin Iwazawa Shoichi Ohue Naoko Hashimoto Osamu Muramoto Takashi Mitani 《European journal of radiology》2013
Purpose
To evaluate the clinical utility and limitations of a computer software program for detecting tumor feeders of hepatocellular carcinoma (HCC) during transarterial chemoembolization (TACE).Materials and methods
Forty-six patients with 59 HCC nodules underwent nonselective digital subtraction angiography (DSA) and C-arm computed tomography (CT) in the same hepatic artery. C-arm CT data sets were analyzed using the software to identify potential tumor feeders during each TACE session. For DSA analysis, 3 radiologists were independently assigned to identify tumor feeders using the DSA images in a separate session. The sensitivity of the 2 techniques in detecting tumor feeders was compared, with TACE findings as the reference standard. Factors affecting the failure of the software to detect tumor feeders were assessed by univariate and multivariate analyses.Results
We detected 65 tumor feeders supplying 59 HCC nodules during TACE sessions. The sensitivity of the software to detect tumor feeders was significantly higher than that of the manual assessment using DSA (87.7% vs. 71.8%, P < 0.001). Multivariate analysis showed that a tumor feeder diameter of <1.0 mm (hazard ratio [HR], 56.3; P = 0.003) and lipiodol accumulation adjacent to the tumor (HR, 11.4; P = 0.044) were the significant predictors for failure to detect tumor feeders.Conclusion
The software analysis was superior to manual assessment with DSA in detecting tumor feeders during TACE for HCC. However, the capability of the software to detect tumor feeders was limited by vessel caliber and by prior lipiodol accumulation to the tumor. 相似文献18.
Mohammad Alaa Abusedera Usama Ahmed Arafa Elsayed Mostafa Ali 《The Egyptian Journal of Radiology and Nuclear Medicine》2014
Purpose
To assess the efficacy of intra-arterial Lidocaine on post-procedural pain and on length of hospital stay in hepatocellular carcinoma (HCC) patients undergoing chemoembolization.Materials and methods
Thirty-nine transarterial chemoembolization (TACE) procedures were carried out for 21 consecutive patients (19M, 2F, age range 52–78).This is a prospective randomized controlled study. Lidocaine was used in 20 TACE and normal saline in 19 TACE. Visual analog scoring was used to assess pain (VAS).Results
Patients’ demographic criteria, Child Pugh, tumor size and doses of chemotherapeutic emulsion and amount of used PV particles were not statistically significantly different between both groups. Average periprocedure VAS was 3.2 versus 7.4 for Lidocaine and Placebo groups, respectively (p = 0.0001). Postprocedure VAS in the Lidocaine group was 4.1 ± 1.6 and that for the Placebo group was 6.1 ± 1.3 (P = 0.001). Mean daily dose of Nalbuphine in the Lidocaine group was 8 mg versus 18 for patients in the Placebo group (p = 0.002). Average length of post procedure hospital stay was 3.7 and 3.8 days for Lidocaine and Placebo groups, respectively (P = 0.36).Conclusions
Intra-arterial administration of buffered Lidocaine before infusing the embolization particle of TACE is safe and effective in dose as low as 50 mg for reducing peri and post-procedural pain and dosage of narcotic analgesics in patients with HCC. 相似文献19.
Jeong-Ah Lee Woo Kyoung Jeong Yongsoo Kim Soon-Young Song Jinoo Kim Jeong Nam Heo Choong Ki Park 《European journal of radiology》2013
Objectives
To evaluate the feasibility of diagnosing recurrence of HCC after TACE color-coded iodine CT (CICT) based on arterial phase scans obtained by a dual-energy CT (DECT) scanner.Methods
A CICT scan was acquired from an iodine map after applying material decomposition of the liver tissue and setting a threshold attenuation level for viable tumors. Two radiologists reviewed both conventional and CICT sets in 31 patients who had a history of TACE for HCC. The performances in detecting local tumor progression (LTP) were evaluated by alternative free-response receiver operating characteristics. The rate of uncertain diagnosis and interobserver agreement of the diagnosis were explored. Additionally, the reading time and radiation dose were also investigated.Results
The mean figures of merit of the conventional and CICT sets for LTP were 0.818 and 0.847, respectively (p = 0.459). The rate of uncertain diagnosis was significantly decreased in CICT sets (34.5% vs. 0%), and interobserver agreement was improved (k = 0.527 vs. 0.718). On the CICT set, mean reading time was reduced by 49 s and mean radiation dose was also decreased by 18.3% when replacing the non-contrast CT with CICT.Conclusions
CICT is comparable to conventional liver CT protocol in demonstrating viable HCCs, while it allows a reduction in radiation dose. 相似文献20.
Takeshi Yoshizako Akihiko Wada Taro Takahara Thomas C. Kwee Megumi Nakamura Koji Uchida Shinji Hara Peter R. Luijten Hajime Kitagaki 《European journal of radiology》2012