Diffusion-weighted Whole-body Imaging With Background Body Signal Suppression Research Articles

Basic MRI Study in the Imaging Direction of a Diffusion-weighted Whole Body Imaging with Background Body Signal Suppression

A diffusion-weighted whole body imaging with background body signal suppression (DWIBS) is usually imaged as a whole body with Transverse (Tra). However, Tra has a large number of stations and a larger number than Coronal (Cor), so the scan time is longer. There are also drawbacks, such as signal unevenness between series. It is known that the effect of distortion is large in Cor. There is no report on it in Sagittal (Sag). Therefore, in this study, we focused on Sag and examined the imaging time, image distortion, fat suppression effect, and continuity between stations. In the examination by the phantom, the scan time was the shortest for Cor and the longest for Sag. In the strain evaluation, the effect of strain could be suppressed compared to Cor by using a rectangle field of view (FOV) in the anterior to posterior (AP) direction in Tra and Sag. There was no difference in the fat suppression effect depending on the imaging direction. Similar results were obtained in a study of 10 healthy volunteers, with Sag having the best continuity between stations.

Clinical Value of Diffusion-Weighted Whole-Body Imaging with Background Body Signal Suppression (DWIBS) for Staging of Patients with Suspected Head and Neck Cancer.

(1) Background: To determine the importance of diffusion-weighted whole-body MRI with background body signal suppression (DWIBS) in the staging process of patients with suspected head and neck carcinomas. (2) Methods: A total of 30 patients (24 male, 6 female) with a median age of 67 years with clinically suspected head and neck carcinoma with pathologic cervical nodal swelling in ultrasound underwent the staging procedure with computed tomography (CT) and whole-body MRI including DWIBS. (3) Results: In a total of 9 patients, abnormalities in the routine work-up of pretherapeutic staging were found. Five cases of either secondary cancer or distant metastases were only visible in DWIBS, while being missed on CT. One diagnosis was only detectable in CT and not in DWIBS, whereas three diagnoses were recognizable in both modalities. (4) Conclusions: DWIBS in addition to a standard neck MRI in cervical lymphadenopathy suspicious for head and neck cancer yielded additional clinically relevant diagnoses in 17% of cases that would have been missed by current staging routine procedures. DWIBS offered a negative predictive value of 98.78% for ruling out distant metastases or secondary malignancies.

Comparison between diffusion-weighted magnetic resonance and positron-emission tomography in the evaluation of treated lymphomas with mediastinal involvement

BackgroundThe persistence of residual tissue after treatment is frequent in patients with mediastinal lymphomas and it is often characterized by 18F-Flurodeoxyglucose Positron Emission Tomography (18F-FDG PET) uptake. This study aims to investigate the usefulness of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) sequence in residual tissues of treated mediastinal lymphomas and to compare it with 18F-FDG PET-CT.ResultsWe included 21 patients with mediastinal Hodgkin and non-Hodgkin lymphomas who showed residual masses on PET-CT imaging at end of treatment and underwent DWIBS-Magnetic Resonance Imaging (MRI). SUVmax and Apparent Diffusion Coefficient (ADC) values of residual masses were assessed quantitatively, including measurement of mean ADC. 15 patients showed radiotracer uptake at 18F-FDG PET-CT, among them only 3 had positive DWIBS-MRI with low ADC values (median value: 0.90 mm2/s). The mediastinal biopsy in these 3 “double positive” patients confirmed pathological residual tissue. All the patients with positive 18F-FDG PET-CT but negative DWIBS-MRI (n = 18) with high ADC values (median value: 2.05 mm2/s) were confirmed negative by biopsy.ConclusionsDWIBS-MRI examination combined with ADC measurement allowed to discriminate pathological and non-pathological residual tissue in patients with treated mediastinal lymphoma. These preliminary results seem to pave the way for a leading role of the MRI which could be a useful alternative to the 18F-FDG PET/CT.

Feasibility of accelerated whole-body diffusion-weighted imaging using a deep learning-based noise-reduction technique in patients with prostate cancer

PurposeTo assess the possibility of reducing the image acquisition time for diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) by denoising with deep learning-based reconstruction (dDLR). MethodsSeventeen patients with prostate cancer who underwent DWIBS by 1.5 T magnetic resonance imaging with a number of excitations of 2 (NEX2) and 8 (NEX8) were prospectively enrolled. The NEX2 image data were processed by dDLR (dDLR-NEX2), and the NEX2, dDLR-NEX2, and NEX8 image data were analyzed. In qualitative analysis, two radiologists rated the perceived coarseness, conspicuity of metastatic lesions (lymph nodes and bone), and overall image quality. The contrast-to-noise ratios (CNRs), contrast ratios, and mean apparent diffusion coefficients (ADCs) of metastatic lesions were calculated in a quantitative analysis. ResultsThe image acquisition time of NEX2 was 2.8 times shorter than that of NEX8 (3 min 30 s vs 9 min 48 s). The perceived coarseness and overall image quality scores reported by both readers were significantly higher for dDLR-NEX2 than for NEX2 (P = 0.005–0.040). There was no significant difference between dDLR-NEX2 and NEX8 in the qualitative analysis. The CNR of bone metastasis was significantly greater for dDLR-NEX2 than for NEX2 and NEX8 (P = 0.012 for both comparisons). The contrast ratios and mean ADCs were not significantly different among the three image types. ConclusionsdDLR improved the image quality of DWIBS with NEX2. In the context of lymph node and bone metastasis evaluation with DWIBS in patients with prostate cancer, dDLR-NEX2 has potential to be an alternative to NEX8 and reduce the image acquisition time.

Can whole-body MRI replace CT in management of metastatic testicular cancer? A prospective, non-inferiority study.

Concerns of imaging-related radiation exposure in young patients with high survival rates have increased the use of magnetic resonance imaging (MRI) in testicular cancer (TC) stage I. However, computed tomography (CT) is still preferred for metastatic TC. The purpose of this study was to compare whole-body MRI incl. diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) with contrast-enhanced, thoracoabdominal CT in metastatic TC. A prospective, non-inferiority study of 84 consecutive patients (median age 33years) with newly diagnosed metastatic TC (February 2018-January 2021). Patients had both MRI and CT before and after treatment. Anonymised images were reviewed by experienced radiologists. Lesion malignancy was evaluated on a Likert scale (1 benign-4 malignant). Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were calculated on patient and lesion level. The primary outcome was demonstrating non-inferiority regarding sensitivity of MRI compared to CT. The non-inferiority margin was set at 5%. ROC curves and interobserver agreement were calculated. On patient level, MRI had 98% sensitivity and 75% specificity compared to CT. On lesion level within each modality, MRI had 99% sensitivity and 78% specificity, whereas CT had 98% sensitivity and 88% specificity. MRI sensitivity was non-inferior to CT (difference 0.57% (95% CI -1.4-2.5%)). The interobserver agreement was substantial between CT and MRI. MRI with DWIBS was non-inferior to contrast-enhanced CT in detecting metastatic TC disease. www. gov NCT03436901, finished July 1st2021.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in detection and characterization of neoplastic breast lesions

Abstract Background Breast cancer is a major health problem in women and early detection is of prime importance. Objective We aimed to evaluate the role of diffusion-weighted imaging with background body signal suppression (DWIBS) in detection of breast lesions and characterization of these detected lesions. Patients and methods 40 female patients with suspicious 50 breast lesions detected by sonomammography, in addition to the routine protocol that includes T1Wi's, T2Wi's, STIR, DCE-MRI and DWI sequences (with ADC maps) all participants underwent DWIBS sequence (with ADC maps). The histopathology served as reference standard. First, we compared the detectability of breast lesions on DWIBS with that of the DWI. We then compared the ADCs of the malignant lesions (n = 35) to that of the benign lesions (n = 15) in both DWI and DWIBS. Results Thirty seven lesions were detected via DWIBS (detectability of 74.0%) which was less than that of DWI (detectability of 78.0%). In DWIBS, the mean ADC value of the malignant lesions (0.80 ± 0.27 × 10-3mm2/s) was significantly lower than that of the benign lesions (1.40 ± 0.41 × 10-3mm2/s). With a cut-off value of 1.3 × 10-3mm2/s for ADC, DWIBS achieved 85.7% sensitivity and 80% specificity for differentiating between benign and malignant lesions. Conclusion Although it showed lower detectability for breast lesions than DWI, our study suggests that DWIBS is superior to DWI in the characterization of malignant breast lesions.. Also based on ADC, DWIBS provides additional information that may further increase the specificity of breast lesion characterization.

Differentiation of Diffuse Infiltration Pattern in Multiple Myeloma From Hyperplastic Hematopoietic Bone Marrow: Qualitative and Quantitative Analysis Using Whole-Body MRI.

The visual assessment used for diffuse infiltration of multiple myeloma (MM) is inadequate. It can be difficult to differentiate MM from hyperplastic hematopoietic bone marrow (HHBM) because the MRI signal characteristics overlap. To analyze the bone marrow diffuse signal changes on whole-body MRI caused by MM and HHBM. Retrospective. Thirty Four patients with MM (21 men and 13 women), 22 patients with HHBM (9 men and 13 women), and 15 healthy controls (9 men and 6 women). A 3.0 T MRI; diffusion-weighted whole-body imaging with background body signal suppression (DWIBS), modified Dixon T1 fast field echo, and T2 STIR. Three radiologists analyzed the whole-body MRI alone and in combination with apparent diffusion coefficient (ADC) and fat fraction (FF) with qualitative and quantitative analysis. Normalized T1 and T2 signal intensities (nT1 and nT2) and signal-to-noise ratio (SNR) were obtained. Kruskal-Wallis and chi-square tests. The MM group had significantly higher ADC and significantly lower FF than HHBM and control groups. There was no significant difference in nT1, nT2 or SNR between MM and HHBM (P=0.932, P=0.097, and P=0.110, respectively). Receiver operating characteristic (ROC) analysis using ADC and FF cut-off values of 0.47 × 10-3 mm2 /sec and 20.63%, respectively. The AUC was 0.866 for ADC and 0.886 for FF. The quantitative analysis yielded better specificity (observer 1: 81.8% vs. 27.3%; observer 2: 68.2% vs. 22.7%; and observer 3: 72.7% vs. 18.2%) and a higher diagnostic accuracy (observer 1: 82.1% vs. 51.8%; observer 2: 80.4% vs. 50.0%; observer 3: 76.8% vs. 44.6%) than the qualitative analysis. Whole-body MRI combined with DWIBS and mDIXON could be used to differentiate between MM and HHBM. Combining the quantitative ADC and FF with the whole-body MRI improved the specificity and accuracy in differentiating these conditions. 3 TECHNICAL EFFICACY: Stage 2.

Evaluation of Diffuse Bone Marrow Infiltration Pattern in Monoclonal Plasma Cell Diseases by Quantitative Whole-body Magnetic Resonance Imaging

To analyze diffuse infiltration pattern in monoclonal plasma cell diseases by diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) and quantitative chemical-shift encoded MRI. Ninety-nine patients with monoclonal plasma cell diseases and 15 healthy control subjects were retrospectively analyzed. All patients underwent whole-body MRI (including DWIBS and mDIXON Quant) and were divided into three groups: monoclonal gammopathy of undetermined significance (MGUS), smoldering multiple myeloma (SMM), and multiple myeloma (MM). Apparent diffusion coefficient (ADC), fat fraction (FF), and T2* values for each group were calculated then analyzed by one-way ANOVA and receiver operating characteristic curve. Correlations of ADC, FF, and T2* with clinical indices were analyzed with Spearman correlation test. The ADC and T2* values of MM were significantly higher than those of the healthy control, MGUS and SMM (ADC: p=0.003, p=0.003, and p=0.042; T2*: all with p < 0.001). The FF values of MM were significantly lower than those of the healthy control, MGUS and SMM (p < 0.001, p < 0.001 and p=0.034). The ADC, FF, and T2* thresholds for recognizing MM and MGUS+SMM were 0.51×10-3 mm2/s, 31.14%, and 10.53 ms, respectively. The ADC, FF, and T2* values were identified to be significantly associated with bone marrow plasma cells and hemoglobin in patients (all with p < 0.001). ADC, FF, and T2* were significantly correlated with clinical indices related to monoclonal plasma cell diseases. MM with the diffuse infiltration pattern can be distinguished more objectively from MGUS and SMM by quantitative functional MRI parameters.

Quantitative whole-body MR imaging for assessment of tumor burden in patients with multiple myeloma: correlation with prognostic biomarkers.

To assess the quantification of tumor burden in multiple myeloma (MM) patients using whole-body magnetic resonance imaging (MRI) and to identify the correlation between MRI parameters and prognostic biomarkers. We retrospectively analyzed 95 newly diagnosed MM patients treated at our hospital from June 2018 to March 2020. All patients underwent whole-body MRI examination, including diffusion-weighted whole-body imaging with background body signal suppression (DWIBS), modified Dixon chemical-shift imaging (mDIXON), and short TI inversion recovery (STIR) sequences. The MRI presentation was used to determine MM infiltration patterns and calculate apparent diffusion coefficient (ADC) and a fat fraction (FF). The one-way ANOVA and Kruskal-Wallis test were used to compare the differences of these values between DS, ISS, and R-ISS stages in different MM infiltration patterns. Spearman correlation test was used for correlation analysis of ADC and FF against prognostic biomarkers, and two independent sample t-test was used to evaluate the differences of ADC and FF in different free light-chain ratio groups. The MRI presentation was classified into normal pattern (36 patients; 37.9%), diffuse (27 patients; 28.4%), and focal (32 patients; 33.7%) infiltration patterns. Statistically significant ADC and FF differences between different DS, ISS, and R-ISS stages were observed in normal/diffuse infiltration patterns but not in focal infiltration patterns. The ADC and FF of the normal/diffuse infiltration pattern showed correlations with hemoglobin, β2-microglobulin, bone marrow plasma cells, flow cytometry of bone marrow cells, and serum monoclonal protein. In contrast, ADC in focal infiltration patterns was negatively correlated with β2-microglobulin and C-reactive protein. The FF of patients with a normal/diffuse infiltration pattern was higher in the low free light-chain ratio group than that in the high free light-chain ratio group (P=0.023). Our observations indicate that quantitative whole-body functional MRI examination may serve as an effective complement to imaging diagnosis based on morphology and provide further information on the tumor burden of patients with MM.

Whole-body magnetic resonance imaging (WB-MRI) with diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) in prostate cancer: Prevalence and clinical significance of incidental findings.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) is now recommended as a first-line staging modality in prostate cancer patients, and the widespread use of DWIBS may lead to an increased frequency of incidental findings. The aim of this study was to evaluate the prevalence and clinical significance of incidental findings on whole-body magnetic resonance imaging (WB-MRI) with DWIBS. Data from 124 patients with prostate cancer (age, 76.5 ± 5.6 years), who underwent 1.5 T WB-MRI with STIR, TSE-T2, TSE-T1, In/Out GRE, and DWIBS sequences, were retrospectively analyzed. Findings unrelated to prostate cancer were considered as incidental findings and categorized into two groups based on their clinical implications as follows: imaging follow-up or additional examinations was required (significant incidental findings) and no need to additional work-up (non-significant incidental findings). A chi-square test was performed to compare the differences in the prevalence of significant incidental findings based on age (≤75 and>75 years old). A total of 334 incidental findings were found with 8.1% (n = 27) as significant incidental findings. Significant incidental findings were more frequent in patients over 75 years old than those of 75 years old or younger (28.6% vs 11.1%, p = 0.018). Clinically significant incidental findings, which required imaging follow-up or additional examinations, were commonly observed in prostate cancer patients on WB-MRI/DWIBS. Some incidental findings were clinically significant that may lead to changes in treatment strategy. Checking the entire organ carefully for abnormalities and reporting any incidental findings detected are important.

Accuracy and diagnostic value of diffusion-weighted whole body imaging with background body signal suppression (DWIBS) in metastatic breast cancer

BackgroundBreast cancer is the most common malignant tumor among women. The mortality of the patients could be mainly attributed to metastasis and spread of breast cancer to distant sites. The objective of the current study is to evaluate and express the role of diffusion-weighted whole body imaging with background body signal suppression (DWIBS) in detection of osseous and soft tissue metastatic lesions in patients with cancer breast.ResultsThe current prospective study included 50 female patients with pathologically proven breast cancer. The overall sensitivity of DWIBS and STIR were 97.5% and 92.5%, respectively. DWIBS was the most sensitive sequence with highest negative predictive values. DWIBS and STIR were the most sensitive with the highest negative predictive value. Both DWIBS and STIR detected more vertebral metastatic deposits (100% and 97.8%, respectively) and more soft tissue lesions (94.4% for both) than WB DWI and T1WI.ConclusionDWIBS MRI sequence is an effective method for detection of solid organ, bone and lymph node metastasis but not specific for characterization of lesions.

PF315 CLINICAL VALUE OF DIFFUSION‐WEIGHTED WHOLE‐BODY IMAGING WITH BACKGROUND BODY SIGNAL SUPPRESSION IN NEWLY DIAGNOSED LYMPHOMA PATIENTS

Background:18F‐fluoro‐2‐deoxyglucose positron emission tomography/computed tomography (18F‐FDG PET/CT) is the widely used functional imaging method in lymphoma. Although 18F‐FDG PET/CT shows a higher sensitivity for detecting lesions, it has the disadvantage of associated substantial dose of ionizing radiation and may cause radiation‐induced secondary malignancies. Diffusion‐weighted whole‐body imaging with background body signal suppression (DWIBS), a noninvasively functional magnetic resonance imaging (MRI) technique that can probe random microscopic motion of water molecules in the body.Aims:In this study, we evaluate clinical value of DWIBS by comparing the accuracy of DWIBS and 18F‐FDG PET/CT in the staging of newly diagnosed lymphoma patients. Further to investigate the correlation between the minimum apparent diffusion coefficient (ADCmin) and maximum standard uptake value (SUVmax), Ki‐67, international prognostic index (IPI), clinical stages, serum lactate dehydrogenase (LDH) and β2‐microglobulin (β2‐MG).Methods:Fifty‐four newly diagnosed lymphoma patients prospectively underwent both DWIBS and 18F‐FDG PET/CT. Staging was performed with WB‐DWI and 18F‐FDG PET/CT respectively according to the Ann Arbor stage system. For each patient, the ADCmin of the lesion was measured on the ADC map and SUVmax was measured in the lesion with high FDG uptake. The mean value of ADCmin for all measurable lesions per patient was indicated by ADCmean. Pathological specimens were immunohistochemically stained to obtain Ki‐67 positive rates. Serum LDH and β2‐MG level results were collected.Results:A total of 273 lesions, 222 nodal lesions and 51 extra‐nodal lesions, were detected by DWIBS. 18F‐FDG PET/CT showed a total of 271 lesions involved, 207 nodal lesions and 64 extra‐nodal lesions. The agreement of detecting nodal lesions between the two imaging methods was excellent (к = 0.828, p &lt; 0.001). The agreement of detecting extra‐nodal lesions between the two imaging methods was good (к = 0.674, p &lt; 0.001). The agreement of detecting overall lesions (nodal lesions and extra‐nodal lesions) between the two imaging methods was good (к = 0.755, p &lt; 0.001). The two methods were concordant in the staging in 45 (83.3%) patients (к = 0.755, p &lt; 0.001). DWIBS staging and clinical staging were concordant in 45 (83.3%) patients (к = 0.757, p &lt; 0.001). 18F‐FDG PET/CT staging and clinical staging were concordant in 47 (87.0%) patients(к = 0.809, p &lt; 0.001). One hundred and ninety lesions simultaneously obtained ADCmin and SUVmax. Based on 190 lesions, ADCmin and SUVmax were inversely correlated (r = −0.222, p = 0.002). There was no statistically significant difference in ADCmean between different stages and different IPI scores. There were no correlations between ADCmeanand IPI, clinical staging, LDH, β2‐MG. Among 42 patients with biopsy, a significant inversely correlation was observed between ADCmin and Ki‐67 of the biopsy lesions (r = −0.401 p = 0.009).Summary/Conclusion:Our results showed good agreement between DWIBS and PET/CT in staging of newly diagnosed lymphoma patients, and an inversely correlation between ADCmin and SUVmax, ADCmin and the proliferation index Ki‐67. Although the concordance rate between DWIBS staging and clinical staging was slightly lower than that of between PET/CT staging and clinical staging, DWIBS has the advantages of safe and efficient, affordable and non‐ionization radiation. Therefore, DWIBS in the clinical application of lymphoma is still promising.image

Detection of bone metastases through diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) compared with PET/CT 18F-NaF.

e23086 Background: To evaluate a diagnostic test which can allow the comparison between Diffusion-weighted imaging with background suppression (DWIBS) the novel diagnostic modality versus PET/CT 18F-NaF, the gold standard for the diagnosis of bone metastases (BM). Methods: University bioethics committee authorized the protocol. Patients with solid cancer and suspicion of BM (by clinical findings, imaging, and tumor biomarkers), who met inclusion criteria were included and provided their signed informed consent. The DWIBS in a MR 3.0 T was performed first and then the PET/CT 18F-NaF. Each study was interpreted blinded. Statistics to evaluate a diagnostic test were performed. Results: From April 2014 to April 2016, 91 patients (100%) were interviewed, 88 (93.4%) met the inclusion criteria. Nine patients (8%) were excluded: death 3, respiratory failure 2, refused participating 2, pacemaker 1, claustrophobia 1. Seventy-nine patients (86.8%) were included, of which 81.0% (64/79) were women. Primary cancer was: a) breast 73.4 b) prostate 15.2%; c) Non-Hodgkin lymphoma 2.5%; d) cervical 2.5%; e) thyroid 2.5%; f) lung 1.3%; g) colon 1.3%; and h) testicular 1.3%. Diagnostic performance of DWIBS compared to PET/CT 18F-NaF, sensitivity 88.1% (Confidence Interval [CI95%, 73.3-96.0), specificity of 48.7% (CI 95%, 31.9-65.6), PPV of 66.0% (CI 95%, 58.2-73.1), NPV of 78.3% (CI 95%, 59.7-89.7), PLR 1.7 (CI 95%, 1.2-2-4), NLR 0.2 (CI 95%, 0.1-0.6) and prevalence of 53.1% (CI 95%, 41.6-54.5). Results were stratified in quartiles (excellent, good, fair, and poor). Conclusions: DWIBS has excelent sensibility, fair specificity, good PPV, and excellent NPV. These data suggest DWIBS could be used as a proxy of PET/CT 18F-NaF.

Feasibility of diffusion-weighted imaging with DWIBS in staging Hodgkin lymphoma in pediatric patients: comparison with PET/CT

ObjectiveThe aim of the study was to evaluate feasibility of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) method in diagnosing Hodgkin lymphoma in pediatric patients and to compare it with 18F-FDG PET/CT as a gold standard.Materials and methodsEleven patients (median age 14) with newly diagnosed Hodgkin lymphoma were examined with 18F-FDG PET/CT and MRI including whole-body DWIBS sequence (b = 0, 800 s/mm2), before the oncologic treatment. About 26 locations of lymphatic tissues were evaluated visually and quantitatively using ADCmean (DWIBS) and SUVmax (18F-FDG PET/CT), respectively.ResultsAll affected lymph node regions (n = 134) diagnosed in 18F-FDG PET/CT were found with DWIBS, presenting decreased diffusion. Significant correlation was found between ADC and SUV values (R2 = − 0.37; p = 0.0001). Nevertheless, additional 33 regions were recognized only by DWIBS. They were significantly smaller than regions diagnosed by both methods.DiscussionAgreement between DWIBS and 18F-FDG PET/CT for detection and staging of malignant lymphoma is high. DWIBS can be used for the evaluation of pediatric Hodgkin lymphoma.

Application of DWIBS in malignant lymphoma: correlation between ADC values and Ki-67 index.

We investigated the correlation between the apparent diffusion coefficient (ADC) and Ki-67 index using diffusion-weighted whole-body imaging with background body signal suppression (DWIBS), and their utility in evaluating malignant lymphoma cell proliferation. Seventy-four patients with malignant lymphoma underwent DWIBS within 1 week before pathological confirmation. The ADC value was measured at the site of the pathological examination, and specimens were also stained with Ki-67. The ADC values and Ki-67 indices in aggressive non-Hodgkin's lymphoma (NHL), indolent NHL, and Hodgkin's lymphoma (HL) were compared using Spearman's rank correlation coefficient and the Kruskal-Wallis test. The Ki-67 indices and ADC values were inversely correlated (r = -0.289, p = 0.0125); the differences in the Ki-67 index between aggressive NHL, indolent NHL, and HL were significant (p < 0.001); this was confirmed by the Nemenyi test except for indolent NHL vs. HL. The ADC values were significantly different between the types of lymphoma (p = 0.013); the Nemenyi test showed a significant difference only between aggressive NHL and HL. The Ki-67 indices and ADC values are inversely correlated in patients with lymphoma, combining DWIBS and ADC values can evaluate the proliferation level of malignant lymphoma cells noninvasively. • By using DWIBS, malignant lymphoma cell proliferation can be assessed noninvasively. • The ADC value and Ki-67 index are significantly and inversely correlated. • The ADC values were lower in aggressive NHL than in HL. • The ADC values of aggressive and indolent NHL were not significantly different.

Diagnostic accuracy of diffusion-weighted whole-body imaging with background body signal suppression/T2-weighted image fusion for the detection of abdominal solid cancer.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) images show significant contrast for cancer tissues against non-cancerous tissues. Fusion of a DWIBS and a T2-weighted image (DWIBS/T2) can be used to obtain functional, as well as anatomic, information. In the present study, the performance of DWIBS/T2 in the diagnosis of abdominal solid cancer was evaluated. The records of 14 patients were retrospectively analyzed [5 patients with hepatocellular carcinoma (HCC), 4 with metastatic liver cancer, 3 with pancreatic cancer, 1 with renal cellular carcinoma and 1 with malignant lymphoma of the para-aortic lymph node]. T1WI and T2WI scans did not detect pancreatic cancer in certain cases, whereas DWIs and DWIBS/T2 clearly demonstrated pancreatic cancer in all cases. In addition, metastatic liver cancer and HCC were successfully detected with abdominal US and CECT; however, US did not detect pancreatic cancer in 1 case, while CECT and DWIBS/T2 detected pancreatic cancer in all cases. In conclusion, the diagnostic performance of DWIBS/T2 was the same as that of abdominal US and CECT in detecting primary and metastatic liver cancer. DWIBS/T2 enabled the diagnosis of pancreatic cancer in cases where it was not detected with US, T1WI or T2WI.

MR neurography for the evaluation of CIDP.

To visualize peripheral nerves in patients with chronic inflammatory demyelinating polyneuropathy (CIDP), we used MR imaging. We also quantified the volumes of the brachial and lumbar plexus and their nerve roots. Thirteen patients with CIDP and 12 healthy volunteers were enrolled. Whole-body MR neurography based on diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) was performed. Peripheral nerve volumes were calculated from serial axial MR images. The peripheral nervous system was visualized with 3-dimensional reconstruction. Volumes ranged from 8.7 to 49.5 cm3 /m2 in the brachial plexus and nerve roots and from 10.2 to 53.5 cm3 /m2 in the lumbar plexus and nerve roots. Patients with CIDP had significantly larger volumes than controls (P < 0.05), and volume was positively correlated with disease duration. MR neurography and the measurement of peripheral nerve volume are useful for diagnosing and assessing CIDP. Muscle Nerve 55: 483-489, 2017.

Diffusion-weighted whole-body imaging with background body signal suppression/T2-weighted image fusion of gastrointestinal cancers.

Diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) yields positive results for cancer against the surrounding tissues. The combination of DWIBS and T2-weighted images (DWIBS/T2) in the diagnosis of gastrointestinal tract cancers was retrospectively analyzed in the present study. Patients were subjected to magnetic resonance imaging after cancer was diagnosed through specimens obtained via biopsy or endoscopic mucosal resection. Sixteen patients were assessed between July, 2012 and June, 2013 and the correlation between detection with DWIBS/T2 and T staging was analyzed. Regarding patients who underwent surgery, the correlation between detection with DWIBS/T2 and the diameter or depth of invasion was analyzed. All cancers that had advanced to >T2 stage were detectable by DWIBS/T2, whereas all cancers staged as <T1 were not (P<0.0001). Tumors that were undetected by DWIBS/T2 had a mean diameter of 1.53±0.25 cm, whereas those detected had a mean diameter of 3.63±1.88 cm; however, the difference was not statistically significant (P=0.1053). Cancers invading beyond the muscularis propria were detectable by DWIBS/T2, while those which had not invaded the mucosa were not (P=0.0476). In conclusion, DWIBS/T2 was able to positively identify gastrointestinal tract cancers at an advanced stage (>T2) or invading beyond the muscularis propria.

Negative signals for adenomyomatosis of the gallbladder upon diffusion-weighted whole body imaging with background body signal suppression/T2-weighted image fusion analysis.

Differentiation between adenomyomatosis (ADM) and cancer of the gallbladder is necessary during diagnosis. Diffusion-weighted whole body imaging with background body signal suppression (DWIBS) images are able to indicate cancer and inflammation. The fusion of a DWIBS with a T2 weighted image (DWIBS/T2) facilitates both functional and anatomical investigations. In the present study, patient records and images from patients with surgically confirmed ADM from April 2012 to October 2014 were analyzed retrospectively. The enrolled patients, including 6 men (64.2±13.1 years) and 4 women (57.3±12.4 years) were subjected to DWIBS/T2 during routine clinical practice. The diagnosis of ADM was based on magnetic resonance cholangiopancreatography, transabdominal ultrasonography, and endoscopic ultrasonography; ADM was diagnosed definitively when cystic lesions were observed, indicating the Rokitansky-Aschoff sinus. A single patient was indicated to be positive by DWIBS/T2 imaging. The Rokitansky-Aschoff sinus revealed a relatively high signal intensity; however, it was not as strong as that of the spleen. The signal intensity was also high on an apparent diffusion coefficient map, suggesting T2 shine-through. The thickened wall displayed low signal intensity. The aforementioned results indicate that ADM may be negative upon DWIBS/T2 imaging; one false positive case was determined to be ADM, accompanied by chronic cholecystitis. The majority of patients with ADM displayed negative findings upon DWIBS/T2 imaging, and chronic cholecystitis may cause false positives.

Diagnostic Value of Diffusion-Weighted Whole-Body Imaging with Background Body Signal Suppression for the Detection of Acute Pyelonephritis in Children: Case-Control Study

Background: The objective of this study was to investigate the accuracy of diffusion-weighted whole-body imaging with background body signal suppression (DWIBS) as a diagnostic test for acute pyelonephritis (APN) in children. Methods: Among inpatients under 15 years of age in a primary care setting, we retrospectively reviewed the medical records for 29 febrile children subjected to DWIBS to confirm or exclude APN. To assess the diagnostic value of DWIBS, the subjects were divided into 13 patients clinically diagnosed with APN and 16 non-APN patients. DWIBS findings were divided into positive, indeterminate, and negative based on visual observation. Results: Likelihood ratios for positive, indeterminate, and negative prediction were 6.15 (95% CI, 1.90–19.97), 0.49 (95% CI, 0.13–1.83) and 0.14 (95% CI, 0.03–0.65), respectively. Conclusions: This study is the first to estimate the accuracy of DWIBS for the detection of APN. Initial DWIBS is a sensitive method for the diagnosis of APN and can improve diagnostic performance.