Diagnostic Value Of Diffusion-weighted Imaging Research Articles

The Significance of Diffusion-Weighted Imaging and Apparent Diffusion Coefficient in the Diagnosis of Early Acute Interstitial Edematous Pancreatitis.

The study assessed the diagnostic value of diffusion-weighted imaging (DWI) and mean apparent diffusion coefficient (ADC) in early acute interstitial edematous pancreatitis (AIEP). Fifty-six AIEP patients and 60 healthy controls underwent an upper abdominal magnetic resonance (MR) examination. The pancreas diameter and ADC values were measured and analyzed across age and gender groups. Results showed that the pancreas diameter varied with sex and age, with smaller diameters in females and the elderly. Mean ADC values were not significantly affected by age or sex. Signal changes were observed in AIEP patients' images, with DWI showing a higher positive rate than T1WI and T2WI. Comparing the control and AIEP groups, the pancreas diameter was significantly larger in AIEP patients, particularly the pancreatic tail in males. ADC values were significantly lower in AIEP patients, and the difference was more pronounced at b=800 s/mm² compared to b=500 s/mm². Mean ADC exhibited good diagnostic potential for early AIEP, with higher sensitivity and specificity values than serum amylase levels. The area under the receiver operating characteristic (ROC) curve (AUC) indicated that the diagnostic value was better at b=800 s/mm² than at b=500 s/mm². In conclusion, the study found that normal pancreas diameter is influenced by sex and age, with smaller diameters in females and the elderly. Mean ADC values were not affected by these factors. Early AIEP could not be diagnosed solely based on pancreas diameter changes. DWI combined with Mean ADC demonstrated high diagnostic value for early AIEP.

Distribution pattern of medial group retropharyngeal lymph nodes and its implication in optimizing clinical target volume in nasopharyngeal carcinoma.

This study aimed to determine the diagnostic value of diffusion-weighted imaging (DWI) and to elucidate the clinical characteristics of medial group retropharyngeal lymph nodes (RLNs) based on multi-modal imaging. Also, we intended to explore the feasibility of optimizing the CTV60 boundary based on the characteristics of medial group RLNs. A total of 549 patients with nasopharyngeal carcinoma received magnetic resonance imaging (MRI), DWI, and contrast-enhanced computed tomography (CT) to detect and evaluate clinical characteristics of medial group RLNs. [18F]Fluorodeoxyglucose positron emission tomography/computed tomography was utilized to identify fluorodeoxyglucose uptaking and contrast-enhanced CT to ensure the reliability of CTV optimization during radiotherapy. The DESdC (Drinking, Eating, Swallowing Difficulties, and Coughing while Eating or Drinking) score was utilized to evaluate swallowing disability. Fourteen of 549 patients had medial group RLNs with a transverse diameter of 2.0-19.0 mm, which distributed between the upper margin of 1st cervical vertebra (C1) and the upper one-third of C3. Lasso regression and Pearson chi-square test suggested that its occurrence was associated with stage N, bilateral cervical lymph node metastases, especially when the transverse diameter of cervical lymph nodes was > 3cm. The sensitivity of DWI, T2 STIR, and contrast-enhanced CT was 100%, 57.1%, and 21.4%, respectively. We optimized CTV60 of medial group RLNs from the base of skull to the upper edge of C2 excluding specific cases. For patients with CTV60 optimization, radiation dose and volume of swallowing structures decreased obviously. Based on our radiotherapy strategy on CTV60, acute toxicities of enrolled patients were well tolerated. Ninety-six of 549 patients had scores with DESdC score. Eighty-three patients scored 1, seven patients scored 2, one patient scored 3, and three patients scored 4. The median interval from the onset of symptoms was 72 (4-114) months. The 5-year overall survival, progression-free survival, local recurrence-free survival, and distant metastasis-free survival were 87%, 80%, 93%, and 85%, respectively. None of the patients with regional recurrence happened in the optimized region. DWI possesses superiorities in displaying lymph nodes. Based on the low incidence of the medial RLNs, CTV60 of medial group RLNs from the base of skull to the upper edge of C2 is feasible and has dosimetric advantages for protecting swallowing structures.

Using MRI appendicitis scale and DWI for the diagnosis of acute appendicitis in pregnant women.

To assess the performance of MRI scale for the diagnosis of acute appendicitis in pregnant women and to determine the added diagnostic value of diffusion-weighted imaging (DWI). From January 2018 to December 2020, 80 patients were included. All MRI were performed with a 1.5-Tesla scanner with anterior array body coil. This analysis included (1) T2-weighted imaging (T2WI), (2) fat-saturated T2WI, and (3) DWI. Two radiologists blinded to the diagnosis recorded their assessment of four findings: appendiceal diameter, appendiceal wall thickness, luminal mucus, and periappendiceal inflammation. The MRI scale of acute appendicitis which ranged from 0 to 4 was determined from these factors. An additional one point was added to the MRI appendicitis scale in those patients with evidence of appendiceal restricted diffusion on DWI. The diagnostic values and predictive factors were computed. Multivariate analysis demonstrated that the calculated MRI appendicitis scale was a significant independent predictor of acute appendicitis with a sensitivity of 96.6%, specificity of 90.2%, and PPV of 84.8%. The odds ratio of appendicitis is increased by 22.3 times for every increase in one point on the MRI appendicitis scale. Therefore, the addition of one point for restricted diffusion in the appendix on DWI imaging can add substantial value, both positive and negative predictive value, towards making an accurate diagnosis of acute appendicitis. MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. Incorporation of diffusion weighted imaging to MRI can improve diagnosis of acute appendicitis. MRI appendicitis scale is an objective and significant independent predictor of acute appendicitis in pregnant women. Incorporation of DWI/ADC map to MRI examinations can improve diagnosis of acute appendicitis in pregnant women. • MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. • The odds ratio of appendicitis can be increased by 22.3 times for every increase of one unit in MRI scale. • Incorporation of diffusion-weighted imaging to MRI examinations can add value to the scale (4.2 ± 0.7 vs. 0.7 ± 1.1; p < 0.001) among pregnant women with appendicitis versus pregnant women without appendicitis.

Diagnostic Value of Diffusion-Weighted Imaging with Background Body Signal Suppression (DWIBS) for the Pre-Therapeutic Loco-Regional Staging of Cervical Cancer: A Feasibility and Interobserver Reliability Study.

(1) Background: cervical cancer is one of the leading causes of cancer-related deaths and the fourth most common cancer among women worldwide. Magnetic resonance imaging (MRI) is the modality of choice for loco-regional staging of cervical cancer in the primary diagnostic workup beginning with at least stage IB. (2) Methods: we retrospectively analyzed 16 patients with histopathological proven cervical cancer (FIGO IB1−IVA) for the diagnostic accuracy of standard MRI and standard MRI with diffusion-weighted imaging with background body signal suppression (DWIBS) for the correct pre-therapeutic assessment of the definite FIGO category. (3) Results: In 7 out of 32 readings (22%), DWIBS improved diagnostic accuracy. With DWIBS, four (13%) additional readings were assigned the correct major (I−IV) FIGO stages pre-therapeutically. Interobserver reliability of DWIBS was weakest for parametrial infiltration (k = 0.43; CI-95% 0.00−1.00) and perfect for tumor size <2 cm, infiltration of the vaginal lower third, infiltration of adjacent organs and loco-regional nodal metastases (k = 1.000; CI-95% 1.00−1.00). (4) Conclusions: the pre-therapeutic staging of cervical cancer has a high diagnostic accuracy and interobserver reliability when using standard MRI but can be further optimized with the addition of DWIBS sequences when reporting is performed by an experienced radiologist.

Diffusion-Weighted Imaging Combined with Cervical Vascular Ultrasound in the Elderly Patients with Multiple Cerebral Infarction.

Objective This study is aimed at evaluating the diagnostic value of diffusion-weighted imaging combined with cervical vascular ultrasound in the elderly patients with multiple cerebral infarctions and at demonstrating whether the diagnostic value is affected by the history of diabetes. Methods From January 2020 to November 2021, the case data of 30 elderly patients with multiple cerebral infarction diagnosed in our hospital were included. Diffusion-weighted magnetic resonance imaging (DWI) and cervical vascular ultrasound (CAU) were performed, respectively. The diagnosis rates of the simple diffusion-weighted imaging group, the simple cervical vascular ultrasound group, and the diffusion-weighted imaging combined with cervical vascular ultrasound group were compared. Results The median onset time of 30 patients was 26.5 (4.75, 43.0) hours. There were 10 hyperacute patients and 20 acute patients. The proportion of diagnosable patients in the diffusion-weighted imaging group was 83.8% (25/30), which was lower than the proportion of diagnosable patients in the diffusion-weighted imaging combined with cervical vascular ultrasound group, which was 90% (27/30). The difference was statistically significant (χ2 = 16.667; P < 0.001). The ratio of diagnosable patients in the cervical vascular ultrasound group alone was 66.7% (20/30), which was lower than 90% (27/30) in the diffusion-weighted imaging combined with cervical vascular ultrasound group. The difference was statistically significant (χ2 = 6.7; P = 0.010). In the hyperacute phase, the proportion of diagnosable patients in the diffusion-weighted imaging combined with cervical vascular ultrasound group was higher than that in the diffusion-weighted imaging group alone (χ2 = 5.833; P = 0.016) and the cervical vascular ultrasound group alone (χ2 = 2.500; P = 0.004). In the acute phase, the proportion of diagnosable patients in the diffusion-weighted imaging combined with cervical vascular ultrasound group was also higher those that in the diffusion-weighted imaging group alone (χ2 = 9.474; P = 0.002) and the cervical vascular ultrasound group alone (χ2 = 3.158; P = 0.006). The diagnostic accuracy of diffusion-weighted imaging combined with cervical vascular ultrasound was not significantly different between patients with history of diabetes and without history of diabetes (χ2 = 1.014; P = 0.314) Conclusion The combined application of diffusion-weighted imaging and cervical vascular ultrasound has important value in improving the diagnosis rate of multiple cerebral infarction in the elderly, regardless of diabetes history, and it is worthy of clinical application.

Multiparametric Framework Magnetic Resonance Imaging Assessment of Subtypes of Intracranial Germ Cell Tumors Using Susceptibility Weighted Imaging, Diffusion-Weighted Imaging, and Dynamic Susceptibility-Contrast Perfusion-Weighted Imaging Combined With Conventional Magnetic Resonance Imaging.

Intracranial germ cell tumors (iGCTs) are classified into two pathological subtypes (germinomas [GEs] and nongerminomatous germ cell tumors [NGGCTs]), with distinct treatment strategy and prognosis. Accurate preoperative determination of iGCT subtypes is essential to guide clinical decision-making and prognosis assessment. To investigate the diagnostic value of diffusion-weighted imaging (DWI), susceptibility weighted imaging (SWI), and dynamic susceptibility-contrast perfusion-weighted imaging (DSC-PWI) combined with conventional magnetic resonance imaging (cMRI) in finding subtypes of iGCTs. Retrospective. A total of 40 patients (45% male and 55% female) with iGCTs. A 3 T; &lt;T1WI, T2WI, T1WI + C, DWI, SWI, DSC-PWI&gt;. The parameters of DWI and DSC-PWI were calculated based on extracted parameters of multiparametric MRIs. The characteristics of SWI and cMRI were also compared in GEs and NGGCTs. The diagnostic efficacy of the minimum apparent diffusion coefficient (ADCmin), time-to-peak (TTP), relative mean transit time (rMTT), relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV) maps, and cMRI features in iGCT classification was evaluated by receiver operating characteristic curve (ROC) analyses. We calculated the sensitivity, specificity, AUC, and Youden index of the hybrid MR evaluation methods. A prospective cohort (five GEs and five NGGCTs) was designed as a simulation set to test the model. The significance threshold was set at P &lt; 0.01. The ADCmin (1039.100 ± 453.830 vs. 1400.050 ± 394.650), rCBF values (20.650 ± 6.260 vs. 51.170 ± 6.570), and TTP values (24.450 ± 3.160 vs. 28.950 ± 5.120) were significantly lower in GEs than in NGGCTs. The combination of ADCmin, DSC-PWI, and cMRI showed the heights AUC (AUC=0.962). The iGCT multiparametric framework showed the AUC was 0.958 in the simulation set. The iCGT multiparametric framework might be an effective diagnostic approach of iGCT subtype. The application of cMRI (T1WI, T2WI, and Gd-T1WI) with advanced imaging modalities (DWI, SWI, and PWI) had the best performance for classifying iGCT subtypes. 3 TECHNICAL EFFICACY: Stage 2.

Diagnostic value of diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) in differentiation between normal and abnormally thickened endometrium: prospective study

BackgroundDiffusion tensor imaging (DTI) can be beneficial to differentiate between endometrium and other uterine layers. It is believed that it can be used to differentiate between normal and abnormally thickened endometrium. The purpose of this study was to find out the diagnostic value of DTI as an extension of DWI in characterization of abnormally thickened endometrium and differentiate it from normal.ResultsThis study included 68 females, results of 3 of them were excluded (unable to complete the study), so the final number was 65 females subdivided into 2 groups; (A) control: 24 (13 premenopausal and 11 asymptomatic postmenopausal), (B) pathological thickened endometrium: 41 (11 premenopausal and 30 postmenopausal): benign (21 patients) and malignant (20 patients). The collected data was correlated to the histopathological results (as the gold standard) in cases of endometrial pathologies. The mean DW-ADC values for normal, benign, and malignant patients were 1.43 ± 0.13, 1.56 ± 0.17, and 0.86 ± 0.16 respectively and with significant statistical difference between normal and benign endometrial lesions (P value = 0.006), and between normal and malignant endometrial lesions, and between benign and malignant endometrial lesions (P value ˂ 0.001).The DTI-FA mean values for normal, benign, and malignant patients were 0.349 ± 0.08, 0.29 ± 0.09, and 0.299 ± 0.08 respectively and with significant statistical difference between normal and benign endometrial lesions (P value = 0.02), but there is no significant statistical difference regarding DTI-FA values between normal and malignant endometrial lesions or between benign and malignant endometrial lesions (P value ˃ 0.05). Also, there is a significant statistical difference regarding DTI-MD mean values between normal (1.59 ± 0.06) and benign (1.37 ± 0.09), normal and malignant (0.71 ± 0.25), and between benign and malignant endometrial lesions (P value ˂ 0.001). The DT-MD had a higher sensitivity, specificity, and accuracy than both DW-ADC and DT-FA in differentiating normal, benign, and malignant endometrial pathologies.ConclusionDTI (added to DWI) is a valuable non-invasive tool that can increase the accuracy in differentiating normal, benign, and malignant endometrial conditions, helping early management, and decrease the possibility of misdiagnosis.

Diagnostic value of diffusion-weighted imaging and conventional magnetic resonance imaging in testicular tumor

Apparent diffusion coefficient(ADC) of magnetic resonance imaging≤0.90×10-3 mm2/s and T2-hypointensity, intratuminal septa, and peritumoral infiltration could achieve best diagnostic efficiency. ADC values and cyst or necrosis were independent predictors for the differential diagnosis of nonseminomatous germ cell tumor versus seminoma and nonseminomatous germ cell tumor versus lymphoma. ADC value and intratuminal septa were independent predictors for the differential of seminoma versus lymphoma.

MRI-based predictive factors of axillary lymph node status in breast cancer.

To evaluate the diagnostic value of diffusion-weighted imaging (DWI) in combination with conventional MRI in predicting metastatic axillary lymph nodes (ALN) in breast cancer (BC). We reviewed pathological findings and clinical breast MRI examinations of 169 patients with invasive BC who were evaluated at the Hôtel-Dieu de France Hospital in 2009-2015. Morphological parameters and apparent diffusion coefficient (ADC) value were compared with pathological nodal status. Independent t-test/chi-square test and a Pearson correlation analysis were used. With pathological diagnosis as reference, MRI-based interpretations were 87.5% specific and 70.3% sensitive. On conventional MRI, the round shape of lymph nodes (LNs), loss of fatty hilum, irregular margins and hypo-intensity/heterogeneous intensity on T2-weighted sequence were statistically significantly different between metastatic and nonmetastatic groups (P<.001, each). Mean size of metastatic ALN was larger compared with negative ALN (13.9mm vs. 10.9mm, P<.001). LNs≥12mm were associated with higher risk of metastasis (P<.001). ADC value was not significantly different between both groups (P=.862). Conventional MRI using the ALN shape, signal intensity in T2-weighted sequences, loss of fatty hilum, regularity of the margins and size of the LNs can evaluate the axilla with high specificity. ADC value could not be used as a reliable parameter.

Diagnostic value of diffusion-weighted imaging with synthetic b-values in breast tumors: comparison with dynamic contrast-enhanced and multiparametric MRI

ObjectivesTo assess DWI for tumor visibility and breast cancer detection by the addition of different synthetic b-values.MethodsEighty-four consecutive women who underwent a breast-multiparametric-MRI (mpMRI) with enhancing lesions on DCE-MRI (BI-RADS 2–5) were included in this IRB-approved retrospective study from September 2018 to March 2019. Three readers evaluated DW acquired b-800 and synthetic b-1000, b-1200, b-1500, and b-1800 s/mm2 images for lesion visibility and preferred b-value based on lesion conspicuity. Image quality (1–3 scores) and breast composition (BI-RADS) were also recorded. Diagnostic parameters for DWI were determined using a 1–5 malignancy score based on qualitative imaging parameters (acquired + preferred synthetic b-values) and ADC values. BI-RADS classification was used for DCE-MRI and quantitative ADC values + BI-RADS were used for mpMRI.ResultsSixty-four malignant (average = 23 mm) and 39 benign (average = 8 mm) lesions were found in 80 women. Although b-800 achieved the best image quality score, synthetic b-values 1200–1500 s/mm2 were preferred for lesion conspicuity, especially in dense breast. b-800 and synthetic b-1000/b-1200 s/mm2 values allowed the visualization of 84–90% of cancers visible with DCE-MRI performing better than b-1500/b-1800 s/mm2. DWI was more specific (86.3% vs 65.7%, p < 0.001) but less sensitive (62.8% vs 90%, p < 0.001) and accurate (71% vs 80.7%, p = 0.003) than DCE-MRI for breast cancer detection, where mpMRI was the most accurate modality accounting for less false positive cases.ConclusionThe addition of synthetic b-values enhances tumor conspicuity and could potentially improve tumor visualization particularly in dense breast. However, its supportive role for DWI breast cancer detection is still not definite.Key Points• The addition of synthetic b-values (1200–1500 s/mm2) to acquired DWI afforded a better lesion conspicuity without increasing acquisition time and was particularly useful in dense breasts.• Despite the use of synthetic b-values, DWI was less sensitive and accurate than DCE-MRI for breast cancer detection.• A multiparametric MRI modality still remains the best approach having the highest accuracy for breast cancer detection and thus reducing the number of unnecessary biopsies.

Clinical suspicion of spondylodiscitis with equivocal MRI findings: does diffusion-weighted imaging prove helpful here?

Despite the high sensitivity of magnetic resonance imaging (MRI), early detection of spondylodiscitis (SpD) remains challenging due to its low specificity. To assess the diagnostic value of diffusion-weighted imaging (DWI) in suspected cases of SpD with ambiguous early MRI findings in the differentiation of degenerative disorders (DD). In this prospective study, 52 patients suspected of having SpD underwent a whole-spine 3-T MRI scan comprising sagittal DWI. Of 58 conspicuous, T2-weighted, signal increased discs, 39 were successfully evaluated using DWI. Apparent diffusion coefficient (ADC) values and ADC maps were blindly analyzed using the region of interest of the conspicuous disc and a normal adjacent reference disc. Intraindividual ratios (conspicuous disc: reference disc) were calculated. All conspicuous discs showed increased absolute ADC values, which did not differ significantly between SpD (n = 22) and DD (n = 17). However, ADC ratio was significantly higher in SpD vs. DD (P < 0.05). In receiver operating characteristic curve analysis, an ADC ratio threshold of 1.6 resulted in 45% sensitivity and 88% specificity (area under the curve = 0.69) for SpD diagnosis. The absolute ADC value does not provide a reliable diagnosis of SpD. Increased diffusivity can be an indication of infection but should always be discussed in the context of existing disc degeneration.

The diagnostic value of diffusion-weighted imaging in differentiating benign from malignant hepatic lesions

BackgroundDiffusion-weighted imaging (DWI) is a novel imaging technique with growing application in onco-imaging. This modality evaluates the diffusion of water molecules in various tissues, which is restricted in hyper cellular regions such as malignant tissue. Apparent diffusion co-efficient (ADC) is a method which can quantify the degree of restriction in tissues and can have diagnostic roles in characterization of hepatic lesions. In this study, 93 patients with proven hepatic lesions were included. These patients had undergone initial evaluation via ultrasonography and dynamic CT scan, and had a definite diagnosis confirmed by biopsy. These patients underwent DW imaging and ADC values of their lesions were calculated. Patients were divided into two groups, benign and malignant groups, based on their biopsy results; and ADC values of hepatic lesions were compared in the two groups.ResultsThe two groups were gender matched. There was a significant difference in the age distribution between the two groups. Mean ADC values for benign and malignant hepatic lesions were 1.58 ± 0.35 (10-3 mm2/s) and 0.87 ± 0.16 (10-3 mm2/s), respectively. There was a statistically significant differences between benign and malignant hepatic lesions (p value < 10-3). DW imaging had a sensitivity of 97.6% and specificity of 98.7% in detecting malignant hepatic lesions from benign ones (p = 0.0001, AUC = 0.99).ConclusionDW MRI imaging can differentiate malignant and benign liver lesions with high sensitivity and specificity using ADC values generated; furthermore, each subgroup of hepatic lesions could be determined based on ADC values.

Differentiation among Glioblastomas, Primary Cerebral Lymphomas, and Solitary Brain Metastases Using Diffusion-Weighted Imaging and Diffusion Tensor Imaging: A PRISMA-Compliant Meta-analysis

Previous studies showed a high diagnostic value of diffusion-weighted imaging (DWI) and diffusion tensor imaging (DTI) in differentiation among glioblastomas, primary cerebral lymphomas (PCLs), and solitary brain metastases, whereas other studies reported a low or no diagnostic value of DWI and DTI in differentiation among the three types of brain malignant tumors. In order to enhance the strength of evidence, meta-analysis was conducted to summarize results of studies evaluating the diagnostic values of DWI or DTI in differentiation among the three types of brain malignant tumors. Articles evaluating the diagnostic values of DWI or DTI in differentiation among the three types of tumors and published before December 2019 were searched in databases (PubMed, Medline, Web of Science, EMBASE, and Google Scholar). A summary of sensitivity, specificity, positive likelihood ratios (PLR), negative likelihood ratios (NLR), and diagnostic odds ratio (DOR) were calculated from the true positive (TP), true negative (TN), false positive (FP), and false negative (FN) of each study using STATA 12.0 software and Meta-Disc Version 1.4. In addition, the summary receive-operating characteristic (SROC) curve was constructed. Ultimately, we included 19 diagnostic studies (including 735 glioblastomas patients, 31 PCLs patients, and 792 patients with solitary brain metastases). Regarding differentiation between glioblastomas and solitary brain metastases using DWI or DTI, the calculated pooled parameters were as follows: sensitivity, 0.84 [95% confidence interval (CI): 0.78-0.89]; specificity, 0.88 (95% CI: 0.83-0.92); PLR, 7.2 (95% CI: 4.6-11.3); NLR, 0.18 (95% CI: 0.12-0.27); and DOR, 41 (95% CI: 18-93). The analysis showed a significant heterogeneity (sensitivity, I2 = 91.31%, p < 0.01; specificity, I2 = 89.24%, p < 0.01). In conclusion, DWI and DTI showed a moderate diagnostic value for differentiating glioblastomas from solitary brain metastasis. Additionally, large-scale prospective studies are essential to explore differentiation between PCLs and solitary brain metastases using DWI or DTI.

Added value of diffusion-weighted images and dynamic contrast enhancement in multiparametric magnetic resonance imaging for the detection of clinically significant prostate cancer in the PICTURE trial.

To determine the additional diagnostic value of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced imaging (DCE) in men requiring a repeat biopsy within the PICTURE study. PICTURE was a paired-cohort confirmatory study in which 249 men who required further risk stratification after a previous non-magnetic resonance imaging (MRI)-guided transrectal ultrasonography-guided biopsy underwent a 3-Tesla (3T) multiparametic (mp)MRI consisting of T2-weighted imaging (T2W), DWI and DCE, followed by transperineal template prostate mapping biopsy. Each mpMRI was reported using a LIKERT score in a sequential blinded manner to generate scores for T2W, T2W+DWI and T2W+DWI+DCE. Area under the receiver-operating characteristic curve (AUROC) analysis was performed to compare the diagnostic accuracy of each combination. The threshold for a positive mpMRI was set at a LIKERT score ≥3. Clinically significant prostate cancer was analysed across a range of definitions including UCL/Ahmed definition 1 (primary definition), UCL/Ahmed definition 2, any Gleason ≥3 + 4 and any Gleason ≥4 + 3. Of 249 men, sequential MRI reporting was available for 246. There was a higher rate of equivocal lesions (44.6%) using T2W alone compared to the addition of DWI (23.9%) and DCE (19.8%). Using the primary definition of clinically significant disease, there was no significant difference in the overall accuracy between T2W, with an AUROC of 0.74 (95% confidence interval [CI] 0.68-0.80), T2W+DWI at 0.76 (95% CI 0.71-0.82), and T2W+DWI+DCE, with an AUROC of 0.77 (95% CI 0.71-0.82; P = 0.55). The AUROC values remained comparable using other definitions of clinically significant disease including UCL/Ahmed definition 2 (P = 0.79), Gleason ≥3 + 4 (P = 0.53) and Gleason ≥4 + 3 (P = 0.53). Using 3T MRI, a high level of diagnostic accuracy can be achieved using T2W as a single parameter in men with a prior biopsy; however, such a strategy can lead to a higher rate of equivocal lesions.

Application value of diffusion-weighted imaging signal pattern in the qualitative diagnosis of renal lesions with T(2)WI hypointensity

Objective: To analyze the diagnostic value of diffusion-weighted imaging (DWI) signal pattern in renal lesions with T(2)WI hypointensity. Methods: Retrospective analysis was performed on DWI imaging datasets of 135 renal lesions with hypointentsity on T(2)WI confirmed by surgery, biopsy, or follow-up in the First Medical Center of Chinese PLA General Hospital from February 2016 to February 2017.One hundred and thirty-five renal lesions,43 benign lesions(age from 28 to 70 years,mean age was 43.5 years, male 18 lesions and female 25 lesions) and 92 malignant lesions (age from 17 to 86 years, mean age was 54.1 years, male 62 lesions and female 30 lesions). DWI signal pattern was classified into six categories: homogeneously high signal, homogeneously low signal, heterogeneously high signal, high halo signal, high halo and nodular signal, and high nodular signal. The agreement between two observers were tested using kappa statistic. The statistical difference between DWI signal characteristics in benign and malignant lesions was analyzed with Chi-Square test. Diagnostic efficacy in differentiation of benign and malignant renal lesions using DWI signal pattern were calculated. Results: One hundred and thirty-five lesions were detected in 135 cases with T(2)WI hypointensity. There were 43 benign lesions and 92 malignant lesions. The agreement between two observers was very good (kappa value=0.878 6). In renal T(2)WI hypointensity lesions, the proportion of DWI homogeneous high signal, homogeneous low signal, heterogeneous high signal, high halo signal, high halo and nodular signal, high nodular signal was 4.7% (2/43), 25.6% (11/43), 30.2% (13/43), 18.6% (8/43), 11.6% (5/43), 9.3% (4/43), respectively. The proportion of malignant lesions was 10.9% (10/92), 0 (0/92), 17.4% (16/92), 13.0% (12/92), 56.5% (52/92) and 2.2% (2/92), respectively. The difference of high halo and nodules signal and homogeneous low signal was statistically significant (all P<0.01). The sensitivity, specificity, positive prediction value (PPV) and negative prediction value (NPV) of high halo and nodular signal for malignancy were 56.5% (52/92), 88.4%(38/43), 91.2% (52/57) and 48.7%(38/78), respectively and homogeneous low signal for benign lesions were 25.6% (11/43), 100.0% (92/92), 100.0% (11/11) and 74.2% (92/124), respectively. Conclusions: DWI signal features may facilitated the accurate diagnosis of renal lesions with T(2)WI hypointensity. Malignant lesions exhibit a higher propensity with high halo and nodular signal on DWI while benign lesions with homogeneous low signal.

Meta-analysis of diffusion-weighted imaging in the differential diagnosis of renal lesions

PurposeTo assess the diagnostic value of diffusion-weighted imaging (DWI) in distinguishing between renal malignant and benign lesions. Materials and methodsElectronic databases were systematically searched to identify original studies evaluating DWI findings on renal lesions from January 2000 through January 2018. Pooled weighted estimates of sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. A summary receiver operator characteristic (sROC) curve was constructed to calculate the area under the sROC curve (AUC). Publication bias was assessed by using Deeks' asymmetry test. ResultsA total of 15 studies including 1386 renal lesions were eligible in the meta-analysis. The pooled sensitivity and specificity with a corresponding 95% confidence interval (CI) were 0.83 (95% CI: 0.80–0.86) and 0.74 (95% CI: 0.71–0.78), respectively. The PLR, NLR, and DOR were 3.21 (95% CI: 2.39–4.32), 0.24 (95% CI: 0.18–0.30), and 15.95 (95% CI: 11.19–22.71), respectively. The AUC was 0.87 (95% CI: 0.84–0.90). Significant heterogeneity was observed between the included studies. Reference standard, country, and gradient factor were identified as the most important variable sources. No evidence of notable publication bias was reported. ConclusionsDWI is an informative MRI modality in discriminating benign and malignant lesions and exhibits moderately high diagnostic accuracy. However, it remains inconclusive and limited in the absence of an optimal b value and ADC cutoff value. High-quality prospective studies regarding DWI have yet to be conducted to explore optimal imaging parameters and diagnostic thresholds.

Diagnostic value of diffusion-weighted imaging and 18F-FDG-PET/CT for the detection of unknown primary head and neck cancer in patients presenting with cervical metastasis

Background and purposeHead and neck squamous cell carcinoma (HNSCC) may present with cervical metastases without an apparent primary tumor. Detecting the primary tumor results in more targeted treatment. Acquisition of DWI is improving with less artifacts and image distortion. We assessed the diagnostic value of DWI and 18F-FDG-PET/CT for detecting primary tumors in patients presenting with nodal metastasis of an unknown primary HNSCC. Materials and methodsFor this retrospective study we included 31 patients (male/female ratio = 23/8, median age = 66 years, age range = 40–80 years) who presented with a pathologically proven cervical nodal metastasis from HNSCC without overt primary tumor location between January 2013 and November 2016 and underwent both DWI and 18F-FDG-PET/CT. Both modalities were assessed qualitatively and quantitatively. With ROC analysis we determined the optimal cut-off for imaging parameters in separating occult malignancy from benign tissue. ResultsQualitative analysis of MRI including DWI resulted in a sensitivity of 81.3% (95%CI) = 53.7–95.0) and specificity of 73.3% (95%CI = 44.8–91.1). With qualitative scoring of 18F-FDG-PET/CT a sensitivity and specificity of 93.8% (95%CI = 67.8–99.7) and 73.3% (95%CI = 44.8–91.1) were found. With quantitative analysis sensitivity and specificity of SUVmax were 81.3% (95%CI = 53.6–95.0) and 93.3% (95%CI = 66.0–99.7), respectively. Combining DWI and 18F-FDG-PET/CT resulted in a sensitivity of 93.8% (95%CI = 67.7–99.7%) and specificity of 60.0% (95%CI = 32.9–82.5%). ConclusionIn this study on HNSCC patients presenting with clinically UP lesions the diagnostic accuracy of qualitative analysis with DWI and 18F-FDG-PET/CT and quantitative analysis of 18F-FDG-PET/CT using SUVmax were high. Adding DWI did not improve the accuracy of 18F-FDG-PET/CT.

Value of Diffusion-Weighted Imaging Combined with Susceptibility-Weighted Imaging in Differentiating Benign from Malignant Parotid Gland Lesions.

BackgroundThe aim of this study was to investigate the diagnostic value of diffusion-weighted imaging (DWI) in combination with susceptibility-weighted imaging (SWI) for differentiating benign parotid gland lesions from malignant ones.Material/MethodsThis retrospective study was approved by the Ethics Committee of our hospital. A total of 36 patients (26 benign cases and 10 malignant cases) were confirmed by surgical pathology. The apparent diffusion coefficient (ADC), normalized ADC (ADCNormalized), intratumoral susceptibility signals (ITSS), and morphological characteristics were analyzed with SPSS 19.0 software.ResultsThe mean ADC values of parotid gland lesions was not different between malignant and benign lesions (P=0.07), while the differences between ADCNormalized (P=0.026) and ITSS grading (P=0.014) were statistically significant. Logistic regression analysis identified use of ADCNormalized and ITSS as the only independent predictor of malignant lesions (odds ratio 0.038; 95% confidence interval 0.001~0.988; P=0.011) and (odds ratio 4.867; 95% confidence interval 1.442~16.423; P=0.049), respectively. The optimum threshold of the ADCNormalized values was –0.45%, ITSS grade was 2, the corresponding areas under the receiver operating characteristic curve (AUC) were 0.750 and 0.787 respectively, and the combination of the 2 was 0.846.ConclusionsDWI integrated with SWI can significantly improve the diagnostic efficacy in distinguishing benign from malignant parotid lesions.

Added value of diffusion-weighted imaging in hepatic tumors and its impact on patient management

BackgroundTo investigate the added diagnostic value of diffusion-weighted imaging (DWI) of the liver and its impact on therapy decisions in patients with hepatic malignancy.MethodsInterdisciplinary gastrointestinal tumorboard cases concerning patients with hepatic malignancies discussed between 11/2015 and 06/2016 were included in this retrospective, single-center study. Two radiologists independently reviewed the respective liver MR-examination first without, then with DWI. The readers were blinded regarding number, position and size of hepatic malignancies. Cases in which DWI revealed additional findings concerning the hepatic tumor status as compared to conventional sequences alone were presented to experienced members of the interdisciplinary tumor board. In this retrospective setting changes in treatment decisions based on these additional findings in the DWI sequences were recorded.ResultsA total of 87 patients were included. DWI revealed additional findings in 12 patients (13,8%). These new findings had a direct effect on the therapy in 8 patients (9,2%): In 6 patients (6,9%) the surgical/interventional treatment was adapted (n = 5: extended resection, n = 1: with transarterial chemoembolization of a single hepatocellular carcinoma only detectable in DWI); 2 patients (2,3%) received systemic therapy (n = 1: neo-adjuvant, n = 1: palliative) based on the additional findings in DWI. In 4 patients (4.6%) additional DWI findings did not affect the therapeutic decision.ConclusionsDWI is a relevant diagnostic tool in oncologic imaging of the liver. By providing further information regarding tumor load in hepatic malignancies it can lead to a significant change in treatment.

Value of diffusion-weighted imaging in differentiating sellar malignant germ cell tumors from raniopharyngioma

Objective: To investigate the diagnostic value of diffusion-weighted imaging (DWI) and apparent diffusion coefficient(ADC) values in the differentiation of sellar malignant germ cell tumors and raniopharyngioma. Methods: This retrospective study included 36 patients(14 cases of malignant germ cell tumor and 22 patients with raniopharyngioma) with histopathologically-confirmed sellar tumors from January 2013 to April 2017 in the First Affiliated Hospital of Zhengzhou University.All patients underwent conventional MRI and DWI before the treatment. ADC maps were reconstructed, and ADC values of the sellar lesions were calculated and compared between the groups. Diagnostic value of ADC was evaluated by receiver operating characteristic(ROC) curves. Results: The mean ADC values of malignant germ cell tumors were significantly lower than that in raniopharyngioma[(0.93±0.23)×10(-3) mm(2)/s vs (1.69±0.21)×10(-3) mm(2)/s, t=-10.19, P<0.01]. The area under the ROC curves of ADC values diagnosing malignant germ cell tumors and raniopharyngioma was 0.987. The optimal cutoff values of ADC for differential diagnosis of malignant germ cell tumors and raniopharyngioma was 1.52×10(-3) mm(2)/s, the sensitivity, specificity and accuracy was 81.2%, 100%, 88.9%, respectively. ADC value had a high consistency with pathological results (Kappa value was 0.887). Conclusion: Malignant germ cell tumors and raniopharyngioma have different ADC value, which can improve the diagnostic accuracy.