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1.
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
2.
We evaluated the diagnostic ability of diffusion-weighted imaging for the differentiation between lymphomas and carcinomas
in the pharynx and between carcinomas with different histological types in the pharynx. T1-weighted, fat-suppressed T2-weighted,
and diffusion-weighted MR imaging was performed on 14 patients with pharyngeal lymphomas, 26 patients with carcinomas of the
pharynx, 5 patients with adenoidal hypertrophy, and 22 patients with normal tonsils. Apparent diffusion coefficients (ADCs)
were determined by using two b factors (500 and 1,000 s/mm2). The ADCs of lymphomas were significantly smaller (0.454 ± 0.075 × 10−3 mm2/s) than those of carcinomas (0.863 ± 0.238 × 10−3 mm2/s). The ADCs of poorly differentiated and undifferentiated carcinomas (0.691 ± 0.149 × 10−3 mm2/s) were significantly smaller than those of moderately differentiated and well-differentiated carcinomas (0.971 ± 0.221 × 10−3 mm2/s), but were significantly larger than those of lymphomas. When an ADC smaller than 0.560 × 10−3 mm2/s was used for predicting lymphomas, we obtained the highest accuracy of 96%, with 100% sensitivity and 94% specificity,
86% positive predictive value, and 100% negative predictive value. Therefore, ADC measurements effectively differentiate lymphomas
from carcinomas in the pharynx and could be a useful adjunct to biopsy-based development of treatment planning. 相似文献
3.
Aine Sakurada Taro Takahara Thomas C. Kwee Tomohiro Yamashita Seiji Nasu Tomohiko Horie Marc Van Cauteren Yutaka Imai 《European radiology》2009,19(6):1461-1469
The purpose of this study was to assess the value of diffusion-weighted magnetic resonance imaging (DWI) in detecting esophageal
cancer and assessing lymph-node status, compared with histopathological results. DWI was prospectively performed in 24 consecutive
patients with esophageal cancer, using the diffusion-weighted whole-body imaging with background body signal suppression (DWIBS)
sequence. DWIBS images were fused with T2-weighted images, and independently and blindly evaluated by three board-certified
radiologists, regarding primary tumor detectability and lymph-node status. Apparent diffusion coefficients (ADCs) of the primary
tumor and lymph nodes were also measured. Average primary tumor detection rate was 49.4%, average patient-based sensitivity
and specificity for the detection of lymph-node metastasis were 77.8 and 55.6%, and average lymph-node group-based sensitivity
and specificity were 39.4 and 92.6%. There were no interobserver differences among the three readers (P < 0.0001). Mean ADC of detected primary tumors was 1.26 ± 0.29×10−3 mm2/s. Mean ADC of metastatic lymph nodes (1.46 ± 0.35×10−3 mm2/s) was significantly higher (P < 0.0001) than that of nonmetastatic lymph nodes (1.15 ± 0.24 mm2/s), but ADCs of both groups overlapped. In conclusion, this study suggests that DWI only has a limited role in detecting
esophageal cancer and nodal staging. 相似文献
4.
Troost EG Laverman P Philippens ME Lok J van der Kogel AJ Oyen WJ Boerman OC Kaanders JH Bussink J 《European journal of nuclear medicine and molecular imaging》2008,35(10):1803-1811
Purpose Tumour cell hypoxia is a common feature in solid tumours adversely affecting radiosensitivity and chemosensitivity in head
and neck squamous cell carcinomas. Positron emission tomography (PET) using the tracer [18F]fluoromisonidazole ([18F]FMISO) is most frequently used for non-invasive evaluation of hypoxia in human tumours. A series of ten human head and neck
xenograft tumour lines was used to validate [18F]FMISO as hypoxia marker at the microregional level.
Methods Autoradiography after injection of [18F]FMISO was compared with immunohistochemical staining for the hypoxic cell marker pimonidazole in the same tumour sections
of ten different human head and neck xenograft tumour lines. The methods were compared: first, qualitatively considering the
microarchitecture; second, by obtaining a pixel-by-pixel correlation of both markers at the microregional level; third, by
measuring the signal intensity of both images; and fourth, by calculating the hypoxic fractions by pimonidazole labelling.
Results The pattern of [18F]FMISO signal was dependent on the distribution of hypoxia at the microregional level. The comparison of [18F]FMISO autoradiography and pimonidazole immunohistochemistry by pixel-by-pixel analysis revealed moderate correlations. In
five tumour lines, a significant correlation between the mean [18F]FMISO and pimonidazole signal intensity was found (range, r
2 = 0.91 to r
2 = 0.99). Comparison of the tumour lines with respect to the microregional distribution pattern of hypoxia revealed that the
correlation between the mean signal intensities strongly depended on the microarchitecture. Overall, a weak but significant
correlation between hypoxic fractions based on pimonidazole labeling and the mean [18F]FMISO signal intensity was observed (r
2 = 0.18, p = 0.02). For the three tumour models with a ribbon-like microregional distribution pattern of hypoxia, the correlation between
the hypoxic fraction and the mean [18F]FMISO signal intensity was much stronger and more significant (r
2 = 0.73, p < 0.001) than for the tumours with a more homogenous, patchy, microregional distribution pattern of hypoxia.
Conclusion Different patterns of [18F]FMISO accumulation dependent on the underlying microregional distribution of hypoxia were found in ten head and neck xenograft
tumours. A weak albeit significant correlation was found between the mean [18F]FMISO signal intensity and the hypoxic fraction of the tumours. In larger clinical tumours, [18F]FMISO–PET provides information on the tumour oxygenation status on a global level, facilitating dose painting in radiation
treatment planning. However, caution must be taken when studying small tumour subvolumes as accumulation of the tracer depends
on the presence of hypoxia and on the tumour microarchitecture.
An erratum to this article can be found at 相似文献
5.
Raya JG Dietrich O Birkenmaier C Sommer J Reiser MF Baur-Melnyk A 《European radiology》2007,17(11):2872-2879
The feasibility of a diffusion-weighted single-shot fast-spin-echo sequence for the diagnostic work-up of bone marrow diseases
was assessed. Twenty healthy controls and 16 patients with various bone marrow pathologies of the spine (bone marrow edema,
tumor and inflammation) were examined with a diffusion-weighted single-shot sequence based on a modified rapid acquisition
with relaxation enhancement (mRARE) technique; four diffusion weightings (b-values: 50, 250, 500 and 750 s/mm2) in three orthogonal orientations were applied. Apparent diffusion coefficients (ADCs) were determined in the bone marrow
and in the intervertebral discs of healthy volunteers and in diseased bone marrow. Ten of the 20 volunteers were repeatedly
scanned within 30 min to examine short-time reproducibility. Spatial reproducibility was assessed by measuring ADCs in two
different slices including the same lesion in 12 patients. The ADCs of the lesions exhibited significantly higher values,
(1.27 ± 0.32)×10−3 mm2/s, compared with healthy bone marrow, (0.21 ± 0.10)×10−3 mm2/s. Short-time and spatial reproducibility had a mean coefficient of variation of 2.1% and 6.4%, respectively. The diffusion-weighted
mRARE sequence provides a reliable tool for determining quantitative ADCs in vertebral bone marrow with adequate image quality. 相似文献
6.
Balassy C Kasprian G Brugger PC Csapo B Weber M Hörmann M Bankier A Bammer R Herold CJ Prayer D 《European radiology》2008,18(4):700-706
To quantify apparent diffusion coefficient (ADC) changes in fetuses with normal lungs and to determine whether ADC can be
used in the assessment of fetal lung development. In 53 pregnancies (20–37th weeks of gestation), we measured ADC on diffusion-weighted
imaging (DWI) in the apical, middle, and basal thirds of the right lung. ADCs were correlated with gestational age. Differences
between the ADCs were assessed. Fetal lung volumes were measured on T2-weighted sequences and correlated with ADCs and with
age. ADCs were 2.13 ± 0.44 μm2/ms (mean ± SD) in the apex, 1.99 ± 0.42 μm2/ms (mean ± SD) in the middle third, and 1.91 ± 0.41 μm2/ms (mean ± SD) in the lung base. Neither the individual ADC values nor average ADC values showed a significant correlation
with gestational age or with lung volumes. Average ADCs decreased significantly from the lung apex toward the base. Individual
ADCs showed little absolute change and heterogeneity. Lung volumes increased significantly during gestation. We have not been
able to identify a pattern of changes in the ADC values that correlate with lung maturation. Furthermore, the individual,
gravity-related ADC changes are subject to substantial variability and show nonuniform behavior. ADC can therefore not be
used as an indicator of lung maturity. 相似文献
7.
Correlation of apparent diffusion coefficients measured by 3T diffusion-weighted MRI and SUV from FDG PET/CT in primary cervical cancer 总被引:1,自引:0,他引:1
Ho KC Lin G Wang JJ Lai CH Chang CJ Yen TC 《European journal of nuclear medicine and molecular imaging》2009,36(2):200-208
Purpose Diffusion-weighted magnetic resonance imaging (DWI) and fluorodeoxyglucose positron emission tomography/computed tomography
(FDG PET/CT) are oncological feasible techniques. Currently, apparent diffusion coefficient (ADC) measured by DWI and standard
uptake value (SUV) from FDG PET/CT have similar applications in clinical oncology. The aim of this study was to assess the
correlation between ADC and SUV in primary cervical cancer.
Materials and methods Patients with documented primary cervical cancer were recruited. All participants underwent abdominopelvic DWI at 3T and FDG
PET/CT within 2 weeks. For the primary tumor, ADC was measured as minimum ADC (ADCmin) and mean ADC (ADCmean) within the whole tumor by DWI. Maximum SUV (SUVmax) and mean SUV (SUVmean) were measured by FDG PET/CT.
Results A total of 33 patients were included. There was no significant correlation either between ADCmin and SUVmax or between ADCmean and SUVmean. The relative ADCmin (rADCmin) defined as ADCmin/ADCmean ratio was significantly inversely correlated with the relative SUVmax (rSUVmax) defined as SUVmax/SUVmean ratio (r = –0.526, P = 0.0017) in all study patients. A significantly inverse correlation between rADCmin and rSUVmax was observed in patients with adenocarcinoma/adenosquamous carcinoma (r = –0.685, P = 0.0012) and those with well-to-moderate differentiated tumor (r = –0.631, P = 0.0050). No significant correlation was demonstrated in patients with squamous cell carcinoma or poorly differentiated
tumor.
Conclusions The significantly inverse correlation between rADCmin and rSUVmax in primary cervical tumor suggests that DWI and FDG PET/CT might play a complementary role for the clinical assessment of
this cancer type. 相似文献
8.
Lung carcinoma: diffusion-weighted mr imaging--preliminary evaluation with apparent diffusion coefficient 总被引:9,自引:0,他引:9
PURPOSE: To prospectively evaluate diffusion-weighted (DW) magnetic resonance (MR) imaging with a split acquisition of fast spin-echo signals for diffusion imaging (SPLICE) sequence for tissue characterization of lung carcinomas by using apparent diffusion coefficients (ADCs). Materials and METHODS: An institutional review board approved this study; informed consent was obtained from patients. Thirty patients (nine women, 21 men; mean age, 68.0 years) with lung carcinoma underwent DW MR imaging with the SPLICE sequence. ADC of each lung carcinoma was calculated from DW MR images obtained with low and high b values. ADCs of lung carcinomas were statistically compared among histologic types. Nine surgically excised lung carcinomas were evaluated for correlation between ADCs and tumor cellularities. Analysis of variance was used to determine changes in ADCs and histologic lung carcinoma types. Spearman rank correlation was calculated between ADCs and tumor cellularities. RESULTS: ADCs for lung carcinomas were 1.63 x 10(-3) mm(2)/sec +/- 0.5 (mean +/- standard deviation) for squamous cell carcinoma, 2.12 x 10(-3) mm(2)/sec +/- 0.6 for adenocarcinoma, 1.30 x 10(-3) mm(2)/sec +/- 0.4 for large-cell carcinoma, and 2.09 x 10(-3) mm(2)/sec +/- 0.3 for small-cell carcinoma. ADC of adenocarcinoma was significantly higher than that of squamous cell carcinoma and large-cell carcinoma (P < .05). ADCs were 1.59 x 10(-3) mm(2)/sec +/- 0.5 and 1.70 x 10(-3) mm(2)/sec +/- 0.4 for moderately and poorly differentiated squamous cell carcinoma, respectively. ADCs were 2.52 x 10(-3) mm(2)/sec +/- 0.4 and 1.44 x 10(-3) mm(2)/sec +/- 0.3 for well- and poorly differentiated adenocarcinoma, respectively. ADC of well-differentiated adenocarcinoma was significantly higher than that of moderately and poorly differentiated squamous cell carcinoma and poorly differentiated adenocarcinoma (P < .05). With the Spearman rank test, ADCs of lung carcinomas correlated well with tumor cellularities (Spearman coefficient, -0.75; P < .02). CONCLUSION: ADCs of lung carcinomas overlap, but ADCs of well-differentiated adenocarcinoma appear to be higher than those of other histologic lung carcinoma types. 相似文献
9.
Introduction We describe the magnetic resonance (MR) imaging characteristics of dysembryoplastic neuroepithelial tumors (DNT) and discuss
their differential diagnosis.
Material and methods Proton MR spectroscopy (TE 30 and 136 ms), diffusion-weighted and perfusion images were retrospectively evaluated in 22 patients
with pathologically proven DNT (17 male and 5 female, mean age 18.7 years) and 14 control subjects (10 male and 4 female,
mean age 16.9 years). The results from the DNT patients and from the control subjects were compared using an independent sample
t-test and the degree of correlation was tested by Pearson’s correlation.
Results All DNTs were solitary and in a supratentorial cortical or subcortical location (ten temporal, eight frontal and four parietal).
They had low-signal on T1-weighted images and high-signal on T2-weighted images without a prominent mass effect. Additionally
a cystic appearance (six patients, 27.3%), cortical dysplasia (six patients, 27.3%) and contrast enhancement (four patients,
18.2%) were also noted. No significant differences were detected in NAA/Cho, NAA/Cr, NAA/Cho+Cr or Cho/Cr ratios between DNT
and normal brain. DNTs had a significantly higher mI/Cr ratio and apparent diffusion coefficient (ADC) values and lower cerebral
blood values than normal parenchyma (P < 0.001). ADC had the highest correlation with the diagnosis of DNT (r = 0.996) followed by relative cerebral blood volume (rCBV) (r = −0.883) and mI/Cr ratio (r = 0.663).
Conclusion Proton MR spectroscopy, diffusion-weighted and perfusion imaging characteristics of DNTs provide additional information to
their MR imaging findings. The MR spectrum showing a slight increase in mI/Cr ratio, and higher ADC and lower rCBV values
than normal parenchyma help to differentiate DNTs from other cortical tumors, which had higher rCBV and lower ADC values than
DNTs.
This work was presented at the ASNR 45th Annual Meeting 2007. 相似文献
10.
A. C. Heide T. L. Richards E. C. Alvord J. Peterson L. M. Rose 《Magnetic resonance in medicine》1993,29(4):478-484
Diffusion-weighted magnetic resonance imaging (MRI) was compared with T2-weighted MRI in longitudinal studies of experimental allergic encephalomyelitis (EAE), an animal model of multiple sclerosis, in five monkeys (Macaca fascicularis). In a region of the brain that had highly directional myelinated fibers (internal capsule) sequential changes were identified on diffusion-weighted images on and before the day these changes were detected on conventional T2-weighted images. Changes were also identified on diffusion-weighted images in brain areas that did not develop T2-weighted abnormalities. This result suggests that diffusion-weighted image intensities are sensitive to pathologic conditions of the brain that can not be seen on T2-weighted images. 相似文献
11.
R. B. J. de Bondt M. C. Hoeberigs P. J. Nelemans W. M. L. L. G. Deserno C. Peutz-Kootstra B. Kremer R. G. H. Beets-Tan 《Neuroradiology》2009,51(3):183-192
Introduction The aim was to determine the diagnostic accuracy and additional value of diffusion-weighted imaging for detection of malignant
lymph nodes in head and neck squamous cell carcinoma.
Methods Two hundred nineteen lymph nodes, predominantly smaller than 10 mm (95.4%), in 16 consecutive patients were evaluated at 1.5 T.
Lymph nodes were evaluated for maximum short axial diameter, morphological criteria, and apparent diffusion coefficient (ADC)
values (b = 0 and b = 1,000 s/mm2). Sensitivity, specificity, positive and negative predictive values as well as diagnostic odds ratios (DORs) and areas under
the curves (AUCs) of ROC curves were calculated for the various magnetic resonance imaging (MRI) criteria individually and
in combination. Histological examination of lymph nodes in the neck dissection specimen was the gold standard to determine
malignant involvement.
Results The optimal ADC threshold was 1.0 × 10−3 mm2/s. Using this cutoff point, sensitivity and specificity were 92.3% and 83.9%, respectively. When used in combination with
size and morphological criteria, ADC value <1.0 × 10−3 mm2/s was the strongest predictor of presence of metastasis (DOR = 97.6). A model which added ADC values to the other MRI criteria
performed significantly better than a model without ADC values: AUC = 0.98 versus AUC = 0.91 (p = 0.036).
Conclusion In this study, with predominantly small lymph nodes, the ADC criterion is the strongest independent predictor of presence
of metastasis. The use of ADC values in combination with the other MRI criteria significantly improves the discrimination
between malignant and benign lymph nodes. 相似文献
12.
Hoebers FJ Kartachova M de Bois J van den Brekel MW van Tinteren H van Herk M Rasch CR Valdés Olmos RA Verheij M 《European journal of nuclear medicine and molecular imaging》2008,35(3):509-518
Purpose The purpose of this study was to determine the value of 99mTc Hynic-rh-Annexin-V-Scintigraphy (TAVS), a non-invasive in vivo technique to demonstrate apoptosis in patients with head
and neck squamous cell carcinoma.
Methods TAVS were performed before and within 48 h after the first course of cisplatin-based chemoradiation. Radiation dose given
to the tumour at the time of post-treatment TAVS was 6–8 Gy. Single-photon emission tomography data were co-registered to
planning CT scan. Complete sets of these data were available for 13 patients. The radiation dose at post-treatment TAVS was
calculated for several regions of interest (ROI): primary tumour, involved lymph nodes and salivary glands. Annexin uptake
was determined in each ROI, and the difference between post-treatment and baseline TAVS represented the absolute Annexin uptake:
Delta uptake (ΔU).
Results In 24 of 26 parotid glands, treatment-induced Annexin uptake was observed. Mean ΔU was significantly correlated with the mean radiation dose given to the parotid glands (r = 0.59, p = 0.002): Glands that received higher doses showed more Annexin uptake. ΔU in primary tumour and pathological lymph nodes showed large inter-patient differences. A high correlation was observed on
an inter-patient level (r = 0.71, p = 0.006) between the maximum ΔU in primary tumour and in the lymph nodes.
Conclusions Within the dose range of 0–8 Gy, Annexin-V-scintigraphy showed a radiation-dose-dependent uptake in parotid glands, indicative
of early apoptosis during treatment. The inter-individual spread in Annexin uptake in primary tumours could not be related
to differences in dose or tumour volume, but the Annexin uptake in tumour and lymph nodes were closely correlated. This effect
might represent a tumour-specific apoptotic response. 相似文献
13.
Loose D Vermeersch H De Vos F Deron P Slegers G Van de Wiele C 《European journal of nuclear medicine and molecular imaging》2008,35(1):47-52
Purpose The purpose of the study was to report on the prognostic value of 99mTc-hydrazinonicotinamide (HYNIC) Annexin-V single-photon emission computed tomography (SPECT) imaging in patients suffering
from primary squamous cell carcinoma of the head and neck.
Methods Twenty-nine patients diagnosed with a primary untreated head and neck squamous cell carcinoma were included in this study.
In all patients, 99mTc-HYNIC Annexin-V scintigraphy SPECT was performed before treatment instigation. Tumour-to-background ratios (T/N) of the
primary tumour, derived from reconstructed images, as well as clinical variables were obtained in all patients and related
to patient outcome. Median follow-up was 22.6 months (range 4.1–55.8 months).
Results On univariate as well as multivariate analysis, only the 99mTc-HYNIC Annexin-V T/N ratio dichotomized using the group median as cutoff value (T/N ratio of 2) was predictive of recurrence-free
survival (respectively, p = 0.0000 and 0.000). On univariate analysis, only lymph node status dichotomized according to N0 vs N1–N2–N3 disease and
the 99mTc-HYNIC Annexin-V T/N ratio dichotomized using the group median as cutoff value (T/N ratio of 2) were predictive of overall
survival (p = 0.0051 and 0.0000). When both factors were included in the multivariate model, both N status and the 99mTc-HYNIC Annexin-V T/N ratio showed an independent association with overall survival (p = 0.001 for lymph node status and 0.000 for dichotomized 99mTc-HYNIC Annexin-V T/N ratio).
Conclusion
99mTc-HYNIC Annexin-V T/N ratios derived from SPECT provides independent prognostic information on disease-free survival and
overall survival. 相似文献
14.
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
15.
Head and neck lesions: characterization with diffusion-weighted echo-planar MR imaging 总被引:32,自引:0,他引:32
Wang J Takashima S Takayama F Kawakami S Saito A Matsushita T Momose M Ishiyama T 《Radiology》2001,220(3):621-630
PURPOSE: To evaluate whether apparent diffusion coefficients (ADCs) calculated from diffusion-weighted echo-planar magnetic resonance (MR) images can be used to characterize head and neck lesions. MATERIALS AND METHODS: Diffusion-weighted echo-planar MR imaging was performed with a 1.5-T MR unit in 97 head and neck lesions in 97 patients. Images were obtained with a diffusion-weighted factor, factor b, of 0, 500, and 1,000 sec/mm(2), and an ADC map was constructed. The ADCs of lesions, cerebrospinal fluid, and spinal cord were calculated. RESULTS: Acceptable images for ADC measurement were obtained in 81 (84%) patients. The mean ADC of malignant lymphomas, (0.66 +/- 0.17[SD]) x 10(-3) mm(2)/sec (n = 13), was significantly smaller (P <.001) than that of carcinomas. The mean ADC of carcinomas, (1.13 +/- 0.43) x 10(-3) mm(2)/sec (n = 36), was significantly smaller (P =.002) than that of benign solid tumors. The mean ADC of benign solid tumors, (1.56 +/- 0.51) x 10(-3) mm(2)/sec (n = 22), was significantly smaller (P =.035) than that of benign cystic lesions, (2.05 +/- 0.62) x 10(-3) mm(2)/sec (n = 10). No significant differences were seen in the mean ADC of cerebrospinal fluid and of spinal cord among four groups of lesions. When an ADC smaller than 1.22 x 10(-3) mm(2)/sec was used for predicting malignancy, the highest accuracy of 86%, with 84% sensitivity and 91% specificity, was obtained. CONCLUSION: Measurement of ADCs may be used to characterize head and neck lesions. 相似文献
16.
Bisdas S Medov L Baghi M Konstantinou GN Wagenblast J Thng CH Vogl TJ Koh TS 《European radiology》2008,18(4):843-850
Our aim was to compare the perfusion [blood flow (BF)] values obtained by first-pass dynamic contrast-enhanced (DCE) T2-weighted
magnetic resonance (MR) and computed tomography (CT) imaging of squamous cell carcinoma (SCC) in the upper aerodigestive tract
in the same patient population. Seventeen patients with histologically proven primary SCC of the upper aerodigestive tract
were prospectively evaluated. The perfusion CT studies were obtained using a 16-row multi-slice CT scanner running a commercial
software package with a deconvolution-based technique; while the perfusion MR studies (1.5 T) were analysed with in-house-written
MR perfusion software based also on a deconvolution technique. The mean perfusion values of SCC assessed by perfusion CT and
MR imaging were 68.93 ± 31.61 and 81.56 ± 49.25 ml/min/100 g, respectively. The Bland-Altman graph showed a proportional error
in the perfusion values measured by DCE-CT and -MR imaging; however, the degree of agreement was acceptable (95% limits of
agreement: −66.1 to 40.8). Regression analysis of the perfusion values demonstrated significant correlation between the modalities:
BFMR = 1.34 × BFCT – 10.93 (P < 0.0005, r
2 = 0.74). The parametric maps generated by both modalities provided insights into the tumour perfusion, while analysis of
the obtained perfusion values demonstrated that both modalities may be used interchangeably in SCC in the upper aerodigestive
tract. 相似文献
17.
Ahmet Mesrur Halefoglu Evren Yildiz Sen Orhan Tanriverdi Fikriye Yilmaz 《Clinical imaging》2013,37(6):1077-1083
BackgroundThe purposes of our study were to investigate the feasibility of diffusion-weighted imaging in the detection of malignant bladder tumors, with comparison to the high-resolution thin-section fast spin-echo (FSE) T2-weighted MRI, and also to compare the apparent diffusion coefficient (ADC) values of the bladder tumors with the surrounding structures.Material and MethodsFifty-three consecutive patients consisting of 44 males and 9 females who presented with a bladder mass were prospectively enrolled in this study. Mean age was 62.53±12.03 (age range, 33–86 years). These patients were evaluated by high-resolution thin-section FSE T2-weighted and diffusion-weighted MRI for the detection of bladder masses. Following MRI, within 2 weeks, all patients were subjected to either surgery or cystoscopic biopsy, and the obtained histopathological proofs were used as the reference standard. Furthermore, ADC values of the bladder tumors, urine, the normal bladder wall, the central and peripheral zones of the prostate, the seminal vesicule, and the uterus outer myometrium were also calculated. ADC values of the bladder carcinomas and the related surrounding structures were compared as to whether a statistically significant difference was present or not.ResultsIn a total of 47 patients, consisting of 39 males and 8 females, bladder carcinomas were clearly shown as having conspicuous high and intermediate signal intensity masses, relative to the surrounding structures on diffusion-weighted and T2-weighted images, respectively. An 89% sensitivity and a 100% positive predictive value were obtained for both FSE T2-weighted and diffusion-weighted MRI in the diagnosis of bladder carcinoma. Mean ADC values and standard deviations of the bladder tumors and the surrounding structures were as follows: bladder carcinomas (n= 47): 1.28±0.31, normal bladder wall (n= 47): 1.98±0.41, urine (n= 47): 3.12±0.24, seminal vesicle (n= 39): 1.82±0.33, peripheral zone of prostate (n= 39): 1.80±0.29, central zone of prostate (n= 39): 1.55±0.33, and uterus outer myometrium (n= 8): 1.53±0.19. It can be clearly seen that the mean ADC values of the bladder carcinomas were significantly lower than the surrounding structures (P< .05).Conclus?onHigh-resolution thin-section FSE T2 and diffusion-weighted MRI show high diagnostic performance and are comparable in the detection of bladder tumors. Diffusion-weighted MRI provides high quality images of the malignant bladder tumors against a suppressed background signal. Diffusion-weighted MRI using ADC measurements may be useful in the evaluation of tumor invasion to the adjacent organs. 相似文献
18.
Oto A Schmid-Tannwald C Agrawal G Kayhan A Lakadamyali H Orrin S Sethi I Sammet S Fan X 《Emergency radiology》2011,18(6):515-524
This study was conducted to determine the incremental value of diffusion-weighted MR imaging (DW-MRI) over T2-weighted imaging
diagnosing abdominopelvic abscesses and compare apparent diffusion coefficient (ADC) values of abscesses and non-infected
ascites. In this IRB-approved, HIPAA-compliant study, two radiologists retrospectively compared T2-weighted, T2-weighted + DW-MRI
and T2-weighted + contrast enhanced MR images of 58 patients (29 with abscess, 29 with ascites) who underwent abdominal MRI
for abscess detection. Confidence and sensitivity was compared using McNemar’s test. ADC of abscesses and ascites was compared
by t test, and a receiver operating characteristic (ROC) curve was constructed. Detection of abscesses and confidence improved
significantly when T2-weighted images were combined with DW-MRI (sensitivity: observer 1—100%, observer 2—96.6%) or contrast
enhanced images (sensitivity: both observers—100%) compared to T2-weighted images alone (sensitivity: observer 1—65.5%, observer
2—72.4%). All abscesses showed restricted diffusion. Mean ADC of abscesses (observer 1—1.17 ± 0.42 × 10−3 mm2/s, observer 2—1.43 ± 0.48 × 10−3 mm2/s) was lower than ascites (observer 1—3.57 ± 0.68 × 10−3 mm2/s, observer 2—3.42 ± 0.67 × 10−3 mm2/s) (p < 0.01). ROC analysis showed perfect discrimination of abscess from ascites with threshold ADC of 2.0 × 10−3 mm2/s (Az value 1.0). DW-MRI is a valuable adjunct to T2-weighted images diagnosing abdominopelvic abscesses. ADC measurements
may have the potential to differentiate abdominal abscesses from ascites. 相似文献
19.
Goshima S Kanematsu M Kondo H Yokoyama R Kajita K Tsuge Y Shiratori Y Onozuka M Moriyama N 《European journal of radiology》2009,70(2):325-330
Purpose
To correlate hepatic hemangioma enhancement types in gadolinium-enhanced magnetic resonance (MR) images with diffusion-weighted MR findings and apparent diffusion coefficients (ADCs).Materials and methods
Respiratory-triggered diffusion-weighted MR images (TR/TE, 2422/46 ms; parallel imaging factor, 2; b factor, 500 s/mm2; number of averaging, 6) obtained in 35 patients with 44 hepatic hemangiomas diagnosed by gadolinium-enhanced MR and by follow-up imaging were retrospectively evaluated. Hemangiomas were classified into three enhancement types based on gadolinium-enhanced MR imaging findings: type I, early-enhancement type; type II, peripheral nodular enhancement type; type III, delayed enhancement type. Two blinded readers qualitatively assessed lesion sizes and signal intensities on T2-weighted turbo spin-echo and diffusion-weighted images. The ADCs of hemangiomas were also measured.Results
No significant difference was observed between the three enhancement types in terms of signal intensities on T2-weighted images. Signal intensities on diffusion-weighted images were lower in the order type I to III (P < .01), and mean ADCs were 2.18 × 10−3, 1.86 × 10−3, and 1.71 × 10−3 mm2/s for types I, II, and III, respectively (P < .01). No correlation was found between lesion sizes and ADCs.Conclusion
Hepatic hemangiomas were found to have enhancement type dependent signal intensities and ADCs on diffusion-weighted MR images. Further studies will have to substantiate that these diffusion patterns might reflect intratumoral blood flow or perfusion. 相似文献20.
Isabelle Thomassin-Naggara Emile Daraï Charles A. Cuenod Laure Fournier Irwin Toussaint Claude Marsault Marc Bazot 《European radiology》2009,19(6):1544-1552
The purpose of this study was to prospectively assess the contribution of diffusion-weighted MR imaging (DWI) for characterizing
complex adnexal masses. Seventy-seven women (22–87 years old) with complex adnexal masses (30 benign and 47 malignant) underwent
MR imaging including DWI before surgery. Conventional morphological MR imaging criteria were recorded in addition to b
1,000 signal intensity and apparent diffusion coefficient (ADC) measurements of cystic and solid components. Positive likelihood
ratios (PLR) were calculated for predicting benignity and malignancy. The most significant criteria for predicting benignity
were low b
1,000 signal intensity within the solid component (PLR = 10.9), low T2 signal intensity within the solid component (PLR = 5.7),
absence of solid portion (PLR = 3.1), absence of ascites or peritoneal implants (PLR = 2.3) and absence of papillary projections
(PLR = 2.3). ADC measurements did not contribute to differentiating benign from malignant adnexal masses. All masses that
displayed simultaneously low signal intensity within the solid component on T2-weighted and on b
1,000 diffusion-weighted images were benign. Alternatively, the presence of a solid component with intermediate T2 signal and high b
1,000 signal intensity was associated with a PLR of 4.5 for a malignant adnexal tumour. DWI signal intensity is an accurate tool
for predicting benignity of complex adnexal masses. 相似文献