Correlation Of Apparent Diffusion Coefficient Research Articles

Correlation of Apparent Diffusion Coefficient With Proliferation and Apoptotic Indexes in a Murine Model of Fibrosarcoma: Comparison of Four Methods for MRI Region of Interest Positioning.

Diffusion-weighted imaging (DWI) has demonstrated great potential in predicting the expression of tumor cell proliferation and apoptosis indexes. To evaluate the impact of four region of interest (ROI) methods on interobserver variability and apparent diffusion coefficient (ADC) values and to examine the correlation of ADC values with Ki-67, Bcl-2, and P53 labeling indexes (LIs) in a murine model of fibrosarcoma. Prospective, animal model. A total of 22 female BALB/c mice bearing intramuscular fibrosarcoma xenografts. A 3.0 T/T1-weighted fast spin-echo (FSE), T2-weighted fast relaxation fast spin-echo, and DWI PROPELLER FSE sequences. Four radiologists measured ADC values using four ROI methods (oval, freehand, small-sample, and whole-volume). Immunohistochemical assessment of Ki-67, Bcl-2, and P53 LIs was performed. Interclass correlation coefficient (ICC), one-way analysis of variance followed by LSD-t post hoc analysis, and Pearson correlation test were performed. The statistical threshold was defined as a P-value of <0.05. All ROI methods for ADC measurements showed excellent interobserver agreement (ICC range, 0.832-0.986). The ADC values demonstrated significant differences among the four ROI methods. The ADC values for oval, freehand, small-sample, and whole-volume ROI methods showed a moderately negative correlation with Ki-67 (r=-0.623; r=-0.629; r=-0.642, and r=-0.431) and Bcl-2 (r=-0.590; r=-0.597; r=-0.659, and r=-0.425) LIs, but no correlation with P53 LI (r=0.364, P=0.104; r=0.350, P=0.120; r=0.379, P=0.091; r=0.390, P=0.080). The ADC value can be used to evaluate cell proliferation and apoptosis indexes in a murine model of fibrosarcoma, employing the small-sample ROI as a reliable method. 1 TECHNICAL EFFICACY: Stage 3.

Correlation of Apparent Diffusion Coefficient with Gleason Score, TNM Staging, and PI-RADSv2 of Prostate Cancer at 3 Tesla

Correlation of Apparent Diffusion Coefficient with Gleason Score, TNM Staging, and PI-RADSv2 of Prostate Cancer at 3 Tesla

Effect of the Mn/V ratio to optimize the kinetic properties of Na3+xMnxV1-xCr(PO4)3 positive electrode for sodium-ion batteries

Several samples of the Na3+xMnxV1-xCr(PO4)3 series, in which the Mn/V ratio was allowed to vary from 0 to 1, are structural, chemical, and morphologically characterized using helpful solid-state techniques such as XRD diffraction, electron microscopy, and Raman and XPS spectroscopies. These cathode materials are tested by both galvanostatic and voltammetric methods to unveil their electrochemical response. The intermediate compositions showed a biphasic transition and a combination of the profiles belonging to the end member of the series: V4+/V3+ Mn3+/Mn2+ and Mn 4+/ Mn 3+ redox couples. The correlation of apparent diffusion coefficients and the cell internal resistance allowed us to conclude the beneficial effect of intermediate Mn-V composition (x = 0.4) to optimize the electrochemical performance and kinetic properties in sodium-ion cells.

Magnetic resonance imaging texture analyses in lower-grade gliomas with a commercially available software: correlation of apparent diffusion coefficient and T2 skewness with 1p/19q codeletion.

Preoperative prediction of molecular information of lower-grade gliomas (LrGGs) helps to determine the overall treatment strategy as well as the initial surgical strategy. This study aimed to detect magnetic resonance imaging (MRI) texture parameters to predict the molecular signature of LrGGs using a commercially available software and routine MR images. Forty-three patients treated at Keio University Hospital who had World Health Organization grade II or III gliomas were included. All patients having preoperative T1- and T2-weighted, fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted (DW) images were also included. Texture analyses of T2, FLAIR, and apparent diffusion coefficient (ADC) histograms were performed using a commercially available software. Texture parameters including kurtosis, skewness, and entropy were investigated to determine any correlation with the presence or absence of isocitrate dehydrogenase (IDH) mutations, 1p/19q codeletion, and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation. ADC skewness and T2 skewness were significantly associated with 1p/19q codeletion status. ADC skewness of ≥ 0.25 predicted 1p/19q codeletion with a sensitivity and specificity of 80% and 65.2%, respectively (AUC = 0.728). T2 skewness of ≥ - 0.11 predicted 1p/19q codeletion with a sensitivity and specificity of 80% and 91.3%, respectively, (AUC = 0.866). None of the texture parameters were associated with IDH mutation and MGMT promoter methylation. MRI texture analysis using a commercially available software demonstrated that T2 skewness could predict 1p/19q codeletion with high sensitivity and specificity, suggesting a clinical utility.

Apparent diffusion coefficients are closely related with high-risk human papilloma virus infection in cervical squamous cell carcinoma patients.

BackgroundDiffusion-weighted imaging (DWI) is a functional modality that indirectly represents the biological characteristics of cancer. However, the correlation of apparent diffusion coefficients ...

Correlating Placental ADC Values with Gestational Age and Grannum Class in Normal Placentas

Background: Recently there have been attempts to link fetal growth retardation to placental morphology as well as apparent-diffusion coefficient (ADC) values. Objectives: The purpose of this study was to investigate the possible correlation of apparent diffusion coefficient (ADC) values of normal placentas with different gestational ages and various Grannum grades (Gg). Patients and Methods: Thirty-eight women were included in this study. All women with singleton pregnancies referred for fetal MRI who were proven normal in pre/postnatal follow-up were included in the study. All placentas were evaluated by ultrasound trans-abdominally. The placenta was assessed for maximal thickness, subjective shape, presence of possible infarcts, sub-placental, and subchorionic hemorrhage. Placentas were also evaluated for G-grading and signal intensities in T2 half-fourier acquisition single-shot turbo spin-echo (HASTE) images. Diffusion weighted imaging (DWI) images were done using two b-value sets (0, 1000 and 50, 400, 800). Largest possible regions of interest (ROI) were drawn over the placenta and ADC values were correlated with gestational-age and Gg using linear regression and Kruskal-Wallis, respectively. Results: There were 11, 18, 9, 0 patients with normal looking placentas with Gg of 0, 1, 2, and 3 respectively. ADC values obtained from b values of 0, and 1000 show a significant correlation with gestational-age (R2 = 0.60, P = 0.000) and Gg (P = 0.004) respectively, while ADC values obtained from b values of 50, 400, and 800 did not show significant correlation with gestational age (R2 = 0.087, P = 0.073) or Gg (P = 0.236). Conclusion: ADC values which were obtained from sets of b values of 0 and 1000 correlated with placental maturity (both gestational age (GA) and Grannum grades). This can be attributed to lower b-values covering the microperfusion in addition to diffusion characteristics of the tissue.

Can Apparent Diffusion Coefficient Values Assist PI-RADS Version 2 DWI Scoring? A Correlation Study Using the PI-RADSv2 and International Society of Urological Pathology Systems.

The purposes of this study were to assess correlation of apparent diffusion coefficient (ADC) and normalized ADC (ratio of tumor to nontumor tissue) with the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) and updated International Society of Urological Pathology (ISUP) categories and to determine how to optimally use ADC metrics for objective assistance in categorizing lesions within PI-RADSv2 guidelines. In this retrospective study, 100 patients (median age, 62 years; range, 44-75 years; prostate-specific antigen level, 7.18 ng/mL; range, 1.70-84.56 ng/mL) underwent 3-T multiparametric MRI of the prostate with an endorectal coil. Mean ADC was extracted from ROIs based on subsequent prostatectomy specimens. Histopathologic analysis revealed 172 lesions (113 peripheral, 59 transition zone). Two radiologists blinded to histopathologic outcome assigned PI-RADSv2 categories. Kendall tau was used to correlate ADC metrics with PI-RADSv2 and ISUP categories. ROC curves were used to assess the utility of ADC metrics in differentiating each reader's PI-RADSv2 DWI category 4 or 5 assessment in the whole prostate and by zone. ADC metrics negatively correlated with ISUP category in the whole prostate (ADC, τ = -0.21, p = 0.0002; normalized ADC, τ = -0.21, p = 0.0001). Moderate negative correlation was found in expert PI-RADSv2 DWI categories (ADC, τ = -0.34; normalized ADC, τ = -0.31; each p < 0.0001) maintained across zones. In the whole prostate, AUCs of ADC and normalized ADC were 87% and 82% for predicting expert PI-RADSv2 DWI category 4 or 5. A derived optimal cutoff ADC less than 1061 and normalized ADC less than 0.65 achieved positive predictive values of 83% and 84% for correct classification of PI-RADSv2 DWI category 4 or 5 by an expert reader. Consistent relations and predictive values were found by an independent novice reader. ADC and normalized ADC inversely correlate with PI-RADSv2 and ISUP categories and can serve as quantitative metrics to assist with assigning PI-RADSv2 DWI category 4 or 5.

Correlation of Apparent Diffusion Coefficient to cognitive impairment in Relapsing remittent multiple sclerosis (plaque, peri-plaque and Normal appearing white matter)

The purpose of this study was to determine diffusion coefficient (ADC) in plaque, peri-plaque and normal-appearing white matter (NAWM) in multiple sclerosis (MS), compare them with the control and correlate findings with cognitive state. Subjects and methodsSixty-five participants were included and categorized into MS patients with normal cognition (n=25); MS with mild cognitive impairment (n=20) and control group (no MS and normal cognition; n=20). The Montreal Cognitive Assessment was used to determine cognitive state. Mean ADC was measured in plaque, peri-plaques and NAWM, compared with ADC from corresponding white matter in control and correlated with cognitive scores. Chi Square and Pearson correlation coefficient were used. ResultsThe mean ADC of peri-plaque and NAWM in MS group with cognitive impairment was significantly higher than MS group with normal cognition (p<0.001) and control group (p<0.05) respectively. In MS patients with impaired cognition, the mean ADC in peri-plaque and NAWM demonstrated inverse correlations with cognitive state (r=−0.64, p<0.001) and (r=−0.56, p=0.01) respectively. ConclusionsADC values in peri-plaque and NAWM have an inverse correlation with cognition in MS. The ADC is useful for detecting subtle abnormalities in white matter and can be used as a predictor of cognitive state.

Abstract P5-01-10: Correlation of apparent diffusion coefficient with standardized uptake value in invasive lobular carcinoma of breast using in hybrid 18F-FDG PET/MR

Abstract Purpose: To compare the apparent diffusion coefficient (ADC) with maximum standardized uptake values (SUV) derived from combined 18F-FDG PET/MRI in invasive lobular carcinoma (ILC) patients. Methods: From 2012 Aug to 2015 Feb, 53 women with histologically proven ILC (mean age, 50.3 ± 7.7 y-o) underwent hybrid 18F-FDG PET/MR (Siemens Biograph mMR) scan for preoperative assessment. During PET acquisition, simultaneous diffusion-weighted imaging (DWI, b values: 0, 400, 800 s/mm2) was performed using breast coil. ILC over than 2 Cm in size were analyzed. Regions of interest (ROI) were drawn covering the entire ILC on the attenuation-corrected PET-image and the monoexponential ADC-map on PET/MR workstation. All the patients were received surgical treatment within 3 weeks after scan. Spearman rank correlation coefficient (ρ) was calculated to examine the correlation between SUVmax and ADC value. Results: Total 25 ILC (5.4±1.3 cm; 2.1-6.3 cm) of 22 women were enrolled. 24 ILC showed ER (+)/PR (+) and all ILC showed HER2 (-). 15 patients were confirmed metastatic axillary lymph nodes. The mean of SUVmax was 2.14 ± 2.2 (0.91-11.9) and mean of ADC was 1.02 ×10-3 (0.82 -1.31 ×10-3) mm2/s. Higher histologic grade was correlated with higher SUV (ρ = -0.6, p=0.001). And SUV showed inverse correlation with ADC (ρ = -0.48, p=0.016). Conclusion: The present data show inverse correlation between increased glucose-metabolism and cellularity in ILC patients. 18F-FDG PET and DWI thus may offer complementary information for the evaluation of treatment response in ILC. Citation Format: Choi JE, Kang SH, Lee SJ, Kong EJ. Correlation of apparent diffusion coefficient with standardized uptake value in invasive lobular carcinoma of breast using in hybrid 18F-FDG PET/MR. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-01-10.

Diffusion-Tensor Imaging of Thigh Muscles in Duchenne Muscular Dystrophy: Correlation of Apparent Diffusion Coefficient and Fractional Anisotropy Values With Fatty Infiltration.

The purpose of this study is to investigate the correlation of apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values with fatty infiltration in the thigh muscles of patients with Duchenne muscular dystrophy (DMD) using diffusion-tensor imaging (DTI). Twenty-one boys with DMD were recruited. The grade of fatty infiltration and the ADC and FA values of four thigh muscles (rectus femoris, semitendinosus, sartorius, and gracilis) were measured, and the FA and ADC values were compared with the grade of fatty infiltration. Twenty age-matched healthy boys were enrolled as the control group. The differences in the ADC and FA values of the thigh muscles between patients with DMD and the control group were compared. The patients with DMD showed lower FA values and higher ADC values in all measured muscles when compared with the control group. The FA and ADC values were correlated with the grade of fatty infiltration. For the rectus femoris muscle, r = -0.753 and p = 0.007 for FA, and r = 0.685 and p = 0.001 for ADC. For the semitendinosus muscle, r = -0.621 and p = 0.041 for FA, and r = 0.705 and p = 0.021 for ADC. For the sartorius muscle, r = -0.662 and p = 0.027 for FA, and r = 0.701 and p = 0.017 for ADC. For the gracilis muscle, r = -0.618 and p = 0.043 for FA, and r = 0.695 and p = 0.022 for ADC. Damage to the thigh muscles in patients with DMD can be detected by ADC and FA values using DTI. DTI can be used to assess the severity of the disease.

Endometrial cancer: correlation of apparent diffusion coefficient (ADC) with tumor cellularity and tumor grade.

Diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) are widely used for detecting uterine endometrial cancer. The relationships between ADC values and pathological features of endometrial cancer have not yet been established. To investigate whether ADC values of endometrial cancer vary according to histologic tumor cellularity and tumor grade. We retrospectively reviewed 30 pathologically confirmed endometrial cancers. All patients underwent conventional non-enhanced magnetic resonance imaging (MRI) and DWI procedures, and ADC values were calculated. Tumor cellularity was evaluated by counting cancer cells in three high-power ( × 400) fields. The correlation between ADC values and tumor cellularity was assessed using Pearson's correlation coefficient test for statistical analysis. The mean ± standard deviation (SD) ADC value ( ×10(-3) mm(2)/s) of endometrial cancer was 0.85 ± 0.22 (range, 0.55-1.71). The mean ± SD tumor cellularity was 528.36 ± 16.89 (range, 298.0-763.6). ADC values were significantly inversely correlated with tumor cellularity. No significant relationship was observed between ADC values and tumor grade (mean ADC values: G1, 0.88 ± 0.265 × 10(-3) mm(2)/s; G2, 0.80 ± 0.178 × 10(-3) mm(2)/s; G3, 0.81 ± 0.117 × 10(-3) mm(2)/s). There is a significant inverse relationship between ADC values and tumor cellularity in endometrial cancer. No significant differences in average ADC value were observed between G1, G2, and G3 tumors. However, the lower the tumor grade, the wider the SD.

Correlation of apparent diffusion coefficients (ADCs) on diffusion-weighted (DW) magnetic resonance (MR) imaging with lesion size and prostate cancer risk.

48 Background: A negative correlation between ADC values and Gleason risk of prostate cancer (CaP) has been reported by the NIH. We correlate ADC values on DW MR imaging with lesion size and risk stratification of CaP. Methods: Men with abnormal DRE or PSA underwent a 3T MP-MRI (T2, DWI, and DCE) with an endorectal coil. ADC maps were calculated using b values of 0, 500, 1,000 and 1,500; additional b 2000 images were obtained separately. Three radiologists (EB, RV, AR) reviewed and graded all lesions using the 5-point Likert scale and PI-RADS score. A total of 268 men with suspicious lesion (s) on MRI were prospectively enrolled. The UroNav system (Invivo, Florida) was used to perform MR/TRUS fusion-guided prostate biopsies, obtaining one biopsy core in axial and sagittal planes from each lesion. Our institution’s pathologist reviewed all biopsies. Lowest ADC values of suspicious lesions were correlated against lesion size and Gleason risk stratification. Results: The median age and PSA were 65.0 years and 7.4 ng/mL respectively. An average of 1.5 (378/256) suspicious lesions per patient was identified on the MP-MRI. Median volume of MRI target lesions was 0.36 cm3. The cancer detection rate of fusion biopsy on lesion level analysis was 45.2 % (171/378). The mean ± SD ADC values (x 10-6 mm2/sec) for lesions negative and positive for CaP were 1022 ± 260 and 724 ± 223 respectively (p &lt;0.0001). The mean ± SD ADC values (x 10-6 mm2/sec) for lesion size &lt; 0.2 cm3, 0.2 – 0.5 cm3, 0.5 – 1.0 cm3, and &gt; 1 cm3 were 771 ± 246, 677 ± 206, 629 ± 119, and 500 ± 86respectively. Higher risk CaP was associated with lower ADC values with AUC of 0.77 (p=0.0001). The mean ± SD ADC values (x 10-6 mm2/sec) for low (≤6), intermediate (7), and high (8-10) Gleason grade CaP were 845 ± 285, 687± 195, and 628 ± 145 respectively. Conclusions: The ADC value of suspicious lesions on MRI has an inverse correlation with lesion size and prostate cancer risk. It may be a useful in predicting CaP and its clinical significance. Further studies are needed to determine its value in stratifying patients for prostate biopsy, active surveillance and/or treatment.

The correlation of apparent diffusion coefficient values with gender and age in normal adult pancreas

Objective To investigate the effect of gender and age on the apparent diffusion coefficient (ADC) of normal adult pancreas. Methods A total of 383 patients with normal pancreas (290 male,93 female,range from 21 to 78 years of age) were enrolled in this study.The subjects were divided into four groups based on different age (≤40 years,41-50 years,51-60 years and>60 years) with patient number of 56,108,139 and 80,respectively.Breath-hold single-shot echo-planar DWI (b value=0,500 s/mm2) was performed to determine ADCs on all patients.The average ADCs was calculated by four ADCs measured from the head to tail part of the pancreas in each patient.Patients with different age or gender were analyzed by independent-samples t test.Effect of gender on ADCs was analyzed using the Mann-Whitney U test.Relationship between ADCs and age was analyzed using Spearman rank-order correlation test,and Kruskal-Wallis H test was used to compare the ADCs among 4 age groups. Results The median pancreatic ADC values in female group (n=93) [1.60×10-3mm2/s (1.47×10-3-1.77×10-3) mm2/s] was higher than that in male group (n=290) [1.57×10-3mm2/s (1.41×10-3-1.74×10-3) mm2/s].Mann-Whitney U test results showed the mean ADCs was similar between the two groups (Z=1.335,P=0.182).The age distribution was similar between the male[ (52±10) years of age]and female[ (51±11) years of age] groups (t=0.267,P=0.790).The age spectrum showed that there was no correlation between the average ADC values and age (r=0.016,P=0.752).The median ADC values of the four age groups were 1.58×10-3,1.54×10-3,1.59×10-3and 1.57×10-3mm2/s,respectively.Kruskal-Wallis H test showed no significant difference of mean ADCs among the age groups (χ2=2.15,P=0.542). Conclusion There is no correlation of ADCs between age and gender in normal adult pancreas. Key words: Pancreas; Diffusion magnetic resonance imaging; Age factors; Sex factors

Response to chemotherapy in gastric adenocarcinoma with diffusion‐weighted MRI and 18F‐FDG‐PET/CT: Correlation of apparent diffusion coefficient and partial volume corrected standardized uptake value with histological tumor regression grade

To assess whether changes in diffusion-weighted MRI (DW-MRI) and (18) F-fluoro-2-deoxyglucose positron emission tomography/computed tomography ((18) F-FDG PET/CT), correlate with treatment response to neoadjuvant therapy (NT), as expressed by tumor regression grade (TRG), from locally advanced gastric adenocarcinoma (GA). Seventeen patients underwent both DW-MRI and (18) F-FDG-PET/CT scans before and after the end of NT. Apparent diffusion coefficient (ADC) and mean standardized uptake value (SUV) corrected for partial volume effect (PVC-SUVBW-mean ) were evaluated and compared with histopathological TRG. Pre- and post-NT and percentage changes for ADC and PVC-SUVBW-mean were assessed. Post-NT ADC and ΔADC showed a significant inverse correlation with TRG (r = -0.71; P = 0.0011 and r = -0.78; P = 0.00020, respectively) and significant differences in their mean values were found between responders (TRG 1-2-3) and nonresponders (TRG 4-5) (P = 0.0009; P = 0.000082, respectively). No correlations with TRG were found for pre-NT ADC and for all PVC-SUVBW-mean values as well as between ΔADC and Δ PVC-SUVBW-mean . DW-MRI seems more accurate than (18) F-FDG-PET/CT and ADC modifications may represent a reproducible tool to assess tumor response for GA.

Correlation of apparent diffusion coefficient with histologic type and grade of lung cancer

背景与目的肺癌的组织学类型和分化程度对于评估肿瘤的生物学行为、预后及选择治疗方式具有重要意义。本研究旨在探讨表观扩散系数（apparent diffusion coefficient, ADC）与肺癌组织学类型和分化程度的相关性。方法符合纳入标准的连续肺癌患者115例，行DWI检查（b=500 s/mm2）并测量病变的ADC值，用t检验及单因素方差分析分析不同组织学类型及不同分化程度间ADC值的差异，用Spearman相关系数分析ADC值与不同分化程度之间的相关性。结果小细胞肺癌（small cell lung cancer, SCLC）与非小细胞肺癌（non-small cell lung cancer, NSCLC）的ADC值差异有统计学意义（P=0.017），且SCLC与鳞癌、腺癌的ADC值差异均有统计学意义（P分别为0.011、0.001）。肺癌不同分化程度间的ADC值差异有统计学意义（P=0.003），且ADC值与病变不同分化程度存在相关性（rs=-0.272, P=0.003）。结论ADC值对术前判断肺癌的组织学类型及分化程度有一定意义：小细胞肺癌的ADC值低，分化程度低的肿瘤的ADC值低。

Correlation of apparent diffusion coefficient with Ki-67 in the diagnosis of gliomas.

To study the correlation between apparent diffusion coefficient (ADC) and Ki-67, a marker of tumor activity, in the diagnosis of gliomas. Conventional magnetic resonance imaging (MRI), enhanced scanning, and diffusion-weighted imaging were performed in 76 patients with pathologically confirmed gliomas. The ADC values were measured at tumor parenchyma and the corresponding contralateral normal brain. The relatively ADC (rADC) values of the tumor parenchyma were calculated. The correlation of the ADC values with tumor grades was analyzed. The expression of Ki-67 was detected by immunohistochemical staining. The correlation between ADC value and Ki-67 in the diagnosis of gliomas was analyzed. The ADC values and rADC values of high-grade gliomas were significantly lower than those of low-grade gliomas. The ADC values of tumor parenchyma were inversely associated with the degree of malignancy of the gliomas (r=-0.898, r=-0.868; P<0.01). The expression of Ki-67 was significantly higher in high-grade gliomas than that in low-grade gliomas. The Ki-67 labeling index in grade 3 and 4 gliomas were (29.48 ± 19.78)% and (31.21 ± 17.50)%, respectively. Both of them were significantly higher than Ki-67 labeling index in low-grade (grade 1 and 2) gliomas [(2.33 ± 2.20)%] (P<0.01). Nevertheless, the Ki-67 labeling index showed no significant difference between grade 3 and 4 gliomas (P>0.05). The expression of Ki-67 was negatively correlated with the ADC values and rADC values in tumor parenchyma (r=-0.627, r=-0.607; P<0.01). The ADC and rADC values of tumor parenchyma can indirectly reflect the proliferation and malignancy of gliomas and therefore can be useful for the grading of glioma.

Role of diffusion weighted magnetic resonance imaging and spectroscopy in the diagnosis and follow-up of hepatolenticular degeneration.

To explore the changes of different brain metabolites during hepatolenticular degeneration using diffusion weighted magnetic resonance imaging (DWI) and magnetic resonance spectroscopy (MRS) in patients with hepatolenticular degeneration and study the correlation of apparent diffusion coefficient(ADC) values and MRS with the different pathological changes. Totally 53 patients with hepatolenticular degeneration were enrolled in this study and divided into DWI high-signal group (n=31) and DWI low-signal group (n=22). Magnetic resonance scan, DWI, and spectroscopy were performed before treatment and 4 months after treatment. The changes of ADC value, N-acetyl aspartate (NAA)/creatine (Cr) ratio, and choline (Cho)/Cr ratio were recorded. Before treatment, the NAA/Cr ratio was significantly higher in the DWI high-signal group than in DWI low-signal group (P=0.002), whereas ADC value and NAA/Cr ratio were significantly lower (P=0.004, P=0.014, respectively). After treatment, the NAA/Cr ratio was still significantly higher in the DWI high-signal group (P=0.036), while the differences of ADC value and Cho/Cr ratio showed no statistical deference (P>0.05). In the DWI high-signal group, the ADC value and NAA/Cr ratio were significantly elevated after treatment (P=0.006, P=0.008), whereas the Cho/Cr ratio showed no significant change (P>0.05). In the DWI low signal group, NAA/Cr ratio was significantly increased after treatment (P=0.015), while the ADC value and Cho/Cr ratio showed no significant change (P>0.05). DWI combined MRS imaging can be used to evaluate the microscopic structure and metabolic changes during copper deposition and thus, compared with the conventional magnetic resonance imaging provide more information on metabolism. Therefore, they can be useful tools in the early diagnosis and efficacy evaluation of hepatolenticular degeneration.

Correlation of apparent diffusion coefficients measured by diffusion-weighted MR imaging and standardized uptake values from FDG PET/CT in metastatic neck lymph nodes of head and neck squamous cell carcinomas

Both diffusion-weighted magnetic resonance imaging and fluorodeoxyglucose positron emission tomography/computed tomography are oncological imaging techniques. The aim of this study was to assess any correlation between apparent diffusion coefficients and standardized uptake value in metastatic neck lymph nodes of head and neck squamous cell carcinomas.

Correlation of apparent diffusion coefficient measured by diffusion‐weighted MRI and clinicopathologic features in pancreatic cancer patients

The aim of this study was to evaluate the clinical usefulness of diffusion-weighted magnetic resonance imaging (DWI) in patients with pancreatic cancer by comparing the apparent diffusion coefficient (ADC) value with clinicopathologic features. Twenty-two consecutive patients (12 men, 10 women; mean age 64.4 years) with pancreatic cancer underwent DWI before surgery. We retrospectively investigated the correlations between tumor ADC value and clinicopathologic features. Apparent diffusion coefficient value was significantly lower for pancreatic cancer than for noncancerous tissue (P < 0.001). Receiver operating characteristic analysis yielded an optimal ADC cutoff value of 1.21 × 10(-3) mm(2)/s to distinguish pancreatic cancer from noncancerous tissue. There was a significant negative correlation between ADC value and tumor size (r = -0.59, P = 0.004) and between ADC value and number of metastatic lymph nodes (r = -0.56, P = 0.007). Tumors with low ADC value had a significant tendency to show high portal venous system invasion (P = 0.02) and extrapancreatic nerve plexus invasion (P = 0.01). Apparent diffusion coefficient value appears to be a promising parameter for detecting pancreatic cancer and evaluating the degree of malignancy of pancreatic cancer.

Correlation of apparent diffusion coefficient at 3T with prognostic parameters of retinoblastoma.

Pathologic prognostic parameters for retinoblastoma have been defined. Our purpose was to correlate ADC values at 3T with prognostic parameters of retinoblastoma. This study included 72 children (30 boys and 42 girls, mean age 19 ± 2.6 months) with retinoblastoma. Pretreatment diffusion-weighted MR imaging was performed on a 3T scanner with b factors of 0, 500, and 1000 seconds/mm(2). ADC values were calculated and pathologic specimens were analyzed. ADC values of the tumors were then correlated with prognostic parameters, including degree of histologic differentiation, tumor size, bilaterality, choroidal invasion, and optic nerve extension. The mean ADC value of retinoblastoma was 0.49 ± 0.12 × 10(-3) mm(2)/s. The ADC values of well- and moderately differentiated tumors were significantly different (P = .007) from poorly and undifferentiated retinoblastoma. There was also a significant difference in the ADC value among small, medium, and large tumors (P = .015), as well as between unilateral and bilateral retinoblastoma (P = .001), and this was independent of the degree of differentiation. The ADC value was also significantly lower (P = .003) when optic nerve invasion was present. There was no correlation of ADC value with growth pattern or choroidal invasion (P = .640 and 0.661, respectively). The ADC value of retinoblastoma was well correlated with the degree of differentiation of the tumor (r = 0.87, P = .007) and inversely correlated with the size of the tumor (r = -0.68, P = .015). ADC correlated with some of the accepted parameters of poor prognosis for retinoblastoma and may serve as a noninvasive prognostic parameter for assessment of newly diagnosed retinoblastoma.