Search

To define the radiological arterial anatomy in mature microminipigs as a pre-clinical research animal model in interventional radiology.Five female microminipigs (weighing 20.9 ± 2.9 kg) were used in this study. Under general anesthesia, computed tomography (CT) angiography was performed using a 16-slice CT scanner. CT was performed 12 s after initiation of an intravenous injection of 40 ml of nonionic contrast media at 3.0 ml/second using a power injector. The transverse CT angiography images were evaluated using a digital imaging and communication in medicine viewer, and the diameters of the following 41 arteries were measured.: ascending aorta, descending aorta, thoracoabdominal aorta, abdominal aorta, pulmonary artery trunk, both pulmonary, brachiocephalic artery, short common bicarotid, both common carotid artery, subclavian, bronchial, internal mammary, celiac, common hepatic, left lateral hepatic, middle hepatic, left hepatic, gastroduodenal, cranial duodenopancreatic, splenic, left gastric, cranial mesenteric, ileocolic , bilateral colic artery, caudal mesenteric, cranial rectal, renal, both external iliac arteries, internal iliac common trunk, and both internal iliac and femoral arteries.The microminipigs' vascular anatomy was the same as domestic pig anatomy and similar to human anatomy. The diameter of the aorta (ascending to abdominal) was 17.1-7.0 mm, iliac and femoral arteries (internal iliac common trunk to femoral artery): 5.5-3.8 mm, pulmonary arteries: 9.3-14.7 mm, and major first aortic branches (e.g., celiac or brachiocephalic artery): 2.2-9.2 mm.This study defined the microminipig arterial anatomy in the trunk.

Background Pancreatic juice is constantly activated by contaminated bile in patients with pancreaticobiliary maljunction (PBM). Here, we report a case of laparoscopic distal pancreatectomy for a patient with PBM and sphincterotomized papilla, resulting in fatal pancreatic fistula. Case presentation A 79-year-old man was diagnosed with pancreatic intraductal papillary mucinous neoplasm and common bile duct stones. Endoscopic sphincterotomy was performed prior to surgery. The pancreatic duct was simultaneously visualized when the contrast agent was injected into the common bile duct. Sudden bleeding was observed from the abdominal drain on postoperative day (POD) 6. Emergent stent graft placement and coil embolization were performed for bleeding from the splenic artery. On POD 9, the drainage fluid changed to yellowish in color with bile contamination. For internal drainage of the digestive fluid, endoscopic retrograde biliary tube and pancreatic drainage tube were placed. On POD 24, second emergent coil embolization was performed for bleeding from the left gastric artery. On POD 25, open abdominal drainage was performed. On POD 32, third emergent coil embolization was performed for bleeding from the gastroduodenal artery. Subsequently, remnant pancreatic resection was performed. On POD 39, massive bleeding was again observed from the abdominal drain. Emergency arterial portography revealed bleeding in the right wall of the superior mesenteric vein. The patient died of hemorrhagic shock on the same day. Conclusions The extreme risk of severe pancreatic fistula after distal pancreatectomy should be considered in patients with PBM and sphincterotomized papilla. In this extraordinary situation, surgeons should promptly decide whether to resect the remnant pancreas to prevent losing the patient.

SignificanceThe water and lipid content of normal breast tissue showed mammary gland characteristics with less influence from the chest wall using six-wavelength time-domain diffuse optical spectroscopy (TD-DOS) in a reflectance geometry.AimTo determine the depth sensitivity of a six-wavelength TD-DOS system and evaluate whether the optical parameters in normal breast tissue can distinguish dense breasts from non-dense breasts.ApproachMeasurements were performed in normal breast tissue of 37 breast cancer patients. We employed a six-wavelength TD-DOS system to measure the water and lipid content in addition to the hemoglobin concentration. The breast density in mammography and optical parameters were then compared.ResultsThe depth sensitivity of the system for water and lipid content was estimated to be ∼15 mm. Our findings suggest that the influence of the chest wall on the water content is weaker than that on the total hemoglobin concentration. In data with evaluation conditions, the water content was significantly higher (plt; 0.001) and the lipid content was significantly lower (plt; 0.001) in dense breast tissue. The water and lipid content exhibited a high sensitivity and specificity to distinguish dense from non-dense breasts in receiver-operating-characteristic curve analysis.ConclusionsWith less influence from the chest wall, the water and lipid content of normal breast tissue measured by a reflectance six-wavelength TD-DOS system, together with ultrasonography, can be applied to distinguish dense from non-dense breasts.

Background We investigated the efficacy of superselective intra-arterial infusion of high-dose cisplatin (CDDP) with concomitant radiotherapy (RADPLAT) using three-dimensional conformal radiotherapy (3DCRT) or intensity-modulated radiotherapy (IMRT), and we analyzed the relationship between the total radiation dose and the treatment outcome in localized maxillary sinus cancer. Methods We examined the cases of 58 patients with localized maxillary sinus cancer who were treated with RADPLAT at our institution from March 2004 to November 2020. These 58 patients include 34 who received 3DCRT and 24 who have received IMRT. Results The median follow-up period was 38.4 months. The median prescribed dose to the local lesion was 66 Gy in the 3DCRT group and 70 Gy in the IMRT group. CDDP (100–120 mg/m2) were administered with a median of 6 cycles once a week. The 5-year local control rate and overall survival rate were 69.9% and 72.2%, respectively. The patients who were treated with 70 Gy had significantly higher local control rate (87.7%) than the patients treated with 60 Gy or lower (41.0%) (p = 0.011). Conclusions The patients who had received 70 Gy using IMRT had significantly higher local control rate. The total dose may have an impact on the local control rate in RADPLAT.

Objectives The 9th International Forum for Liver Magnetic Resonance Imaging (MRI) was held in Singapore in September 2019, bringing together radiologists and allied specialists to discuss the latest developments in and formulate consensus statements for liver MRI, including the applications of gadoxetic acid–enhanced imaging. Methods As at previous Liver Forums, the meeting was held over 2 days. Presentations by the faculty on days 1 and 2 and breakout group discussions on day 1 were followed by delegate voting on consensus statements presented on day 2. Presentations and discussions centered on two main meeting themes relating to the use of gadoxetic acid–enhanced MRI in primary liver cancer and metastatic liver disease. Results and conclusions Gadoxetic acid–enhanced MRI offers the ability to monitor response to systemic therapy and to assist in pre-surgical/pre-interventional planning in liver metastases. In hepatocellular carcinoma, gadoxetic acid–enhanced MRI provides precise staging information for accurate treatment decision-making and follow-up post therapy. Gadoxetic acid–enhanced MRI also has potential, currently investigational, indications for the functional assessment of the liver and the biliary system. Additional voting sessions at the Liver Forum debated the role of multidisciplinary care in the management of patients with liver disease, evidence to support the use of abbreviated imaging protocols, and the importance of standardizing nomenclature in international guidelines in order to increase the sharing of scientific data and improve the communication between centers. Key Points • Gadoxetic acid–enhanced MRI is the preferred imaging method for pre-surgical or pre-interventional planning for liver metastases after systemic therapy. • Gadoxetic acid–enhanced MRI provides accurate staging of HCC before and after treatment with locoregional/biologic therapies. • Abbreviated protocols for gadoxetic acid–enhanced MRI offer potential time and cost savings, but more evidence is necessary. The use of gadoxetic acid–enhanced MRI for the assessment of liver and biliary function is under active investigation.

Purpose To determine the optimal combination of gadoxetate disodium-enhanced magnetic resonance imaging (MRI) findings for the diagnosis of hepatocellular carcinoma (HCC) and to compare its diagnostic ability to that of dynamic computed tomography (CT) in patients with chronic liver disease. Methods This multi-institutional study consisted of two parts: Study 1, a retrospective study to determine the optimal combination of gadoxetate disodium-enhanced MRI findings (decision tree and logistic model) to distinguish HCC (n = 199) from benign (n = 81) or other malignant lesions (n = 95) (375 nodules in 269 patients) and Study 2, a prospective study to compare the diagnostic ability of gadoxetate disodium-enhanced MRI to distinguish HCC (n = 73) from benign (n = 15) or other malignant lesions (n = 12) with that of dynamic CT (100 nodules in 83 patients). Two radiologists independently evaluated the imaging findings (Study 1 and 2) and made a practical diagnosis (Study 2). Results In Study 1, rim or whole enhancement on arterial phase images, signal intensities on T2-weighted/diffusion-weighted/portal venous/transitional/hepatobiliary phase images, and signal drop on opposed-phase images were independently useful for differential diagnosis. In Study 2, the accuracy, sensitivity, negative predictive value, and negative likelihood ratio of the CT decision tree (reader 2) were higher than those of MRI Model 2 (P = 0.015-0.033). There were no other significant differences in diagnostic ability (P = 0.059-1.000) and radiologist-made practical diagnosis (P = 0.059-1.000) between gadoxetate disodium-enhanced MRI and CT. Conclusion We identified the optimal combination of gadoxetate disodium-enhanced MRI findings for HCC diagnosis. However, its diagnostic ability was not superior to that of dynamic CT.

Bleeding is a fatal complication after pancreatectomy. Although coil embolization is a widely accepted treatment option, ischemia of the remaining organs should be prevented. This study reports the successful treatment of intra-abdominal hemorrhage following distal pancreatectomy with en bloc celiac axis resection (DP-CAR) using balloon-assisted coil embolization (BACE). A 59-year-old man was diagnosed with locally advanced pancreatic cancer. The tumor involves the common hepatic artery, splenic artery, and celiac artery. After four cycles of treatment with gemcitabine/nab-paclitaxel, the soft-density masses, surrounding the artery, shrunk. DP-CAR and R0 resections were performed. A minor postoperative pancreatic fistula occurred. Six months postoperatively, the computed tomography showed delayed asymptomatic bleeding from an anterior superior pancreaticoduodenal artery (ASPDA) pseudoaneurysm located near the gastroduodenal artery confluence. BACE was performed by placing a microballoon catheter in the region of confluence of the ASPDA and posterior superior pancreaticoduodenal artery (PSPDA) to prevent coil migration. After inserting the microballoon catheter, coil embolization was performed in the ASPDA. Hepatic blood flow was maintained from the PSPDA. BACE is a useful technique to preserve blood flow to the remnant organs when performing coil embolization for bleeding following a distal pancreatectomy, especially following a DP-CAR.

Objectives To investigate neuroendocrine carcinoma (NEC) of the uterine cervix cases for MRI features and staging, as well as pathological correlations and survival. Results FIGO was I in 42, II in 14, III in 1, and IV in 5 patients. T2-weighted MRI showed homogeneous slightly high signal intensity and obvious restricted diffusion (ADC map, low intensity; DWI, high intensity) throughout the tumor in most cases, and mild enhancement in two-thirds. In 50 patients who underwent a radical hysterectomy and lymphadenectomy without neoadjuvant chemotherapy (NAC), intrapelvic T staging by MRI overall accuracy was 88.0% with reference to pathology staging, while patient-based sensitivity, specificity, and accuracy for metastatic pelvic lymph node detection was 38.5%, 100%, and 83.3%, respectively. During a mean follow-up period of 45.6 months (range 4.3-151.0 months), 28 patients (45.2%) experienced recurrence and 24 (38.7%) died. Three-year progression-free and overall survival rates for FIGO I, II, III, and IV were 64.3% and 80.9%, 50% and 64.3%, 0% and 0%, and 0% and 0%, respectively. Materials and methods Sixty-two patients with histologically surgery-proven uterine cervical NEC were enrolled. Twelve received NAC. Clinical data, pathological findings, and pretreatment pelvic MRI findings were retrospectively reviewed. Thirty-two tumors were pure NEC and 30 mixed with other histotypes. The NECs were small cell type (41), large cell type (18), or a mixture of both (3). Conclusions Homogeneous lesion texture with obvious restricted diffusion throughout the tumor are features suggestive of cervical NEC. Our findings show that MRI is reliable for T staging of cervical NEC.

To compare the detectability of pancreatic ductal adenocarcinoma (PDAC) and liver metastases between Gd-EOB-DTPA- and extracellular contrast materials (ECCMs) contrast-enhanced MR imaging contrast. Two hundred seventy-two patients with suspected pancreatic disease underwent Gd-EOB-DTPA-enhanced MR imaging (EOB group, n = 79) or ECCMs-enhanced MR imaging (ECCM group, n = 193). The ECCM group were administered the following contrast agents: Gd-DTPA (n = 158), Gd-BT-DO3A (n = 28), Gd-DOTA (n = 5), and Gd-DTPA-BMA (n = 2). Signal intensities of pancreatic parenchyma, paraspinal muscle, PDAC (if present), and background noise were measured. The signal intensity ratio (SIR) of the pancreas and tumor-to-pancreas contrast-to-noise ratio (CNR) were also calculated. If present, the conspicuity of PDAC was evaluated with the arterial dominant phase images. Liver metastases, if present, were also evaluated for all sequences. Qualitative and quantitative imaging parameters were compared between EOB and ECCM groups. SIR of the pancreas (P

Purpose: To characterize the non-laminar flow dynamics and resultant decreased wall shear stress (WSS) and high oscillatory shear index (OSI) of the infrarenal abdominal aortic dilatation, cardiac phase-resolved 3D phase-contrast MRI (4D-flow MRI) was performed. Methods: The prospective single-arm study was approved by the Institutional Review Board and included 18 subjects (median 67.5 years) with the dilated infrarenal aorta (median diameter 35 mm). 4D-flow MRI was conducted on a 1.5T MRI system. On 3D streamline images, laminar and non-laminar (i.e., vortex or helical) flow patterns were visually assessed both for the dilated aorta and for the undilated upstream aorta. Cardiac phase-resolved flow velocities, WSS and OSI, were also measured for the dilated aorta and the upstream undilated aorta. Results: Non-laminar flow represented by vortex or helical flow was more frequent and overt in the dilated aorta than in the undilated upstream aorta (P < 0.0156) with a very good interobserver agreement (weighted kappa: 0.82–1.0). The WSS was lower, and the OSI was higher on the dilated aortic wall compared with the proximal undilated segments. In mid-systole, mean spatially-averaged WSS was 0.20 ± 0.016 Pa for the dilated aorta vs. 0.68 ± 0.071 Pa for undilated upstream aorta (P < 0.0001), and OSI on the dilated aortic wall was 0.093 ± 0.010 vs. 0.041 ± 0.0089 (P = 0.013). The maximum values and the amplitudes of the WSS at the dilated aorta were inversely proportional to the ratio of dilated/undilated aortic diameter (r = −0.694, P = 0.0014). Conclusion: 4D-flow can characterize abnormal non-laminar flow dynamics within the dilated aorta in vivo. The wall of the infrarenal aortic dilatation is continuously and increasingly affected by atherogenic stimuli due to the flow disturbances represented by vortex or helical flow, which is reflected by lower WSS and higher OSI.

To evaluate the optimal imaging protocol and the feasibility of intranodal dynamic contrast-enhanced computed tomography lymphangiography (DCCTL) in microminipigs. The Committee for Animal Research and Welfare provided university approval. Five female microminipigs underwent DCCTL after inguinal lymph node injection of 0.1 mL/kg of iodine contrast media at a rate of 0.3 mL/min with three different iodine concentrations: group 1, 75 mgI/mL; group 2, 150 mgI/mL; and group 3, 300 mgI/mL. The CT values of the venous angle, thoracic duct (TD), cisterna chyli, iliac lymphatic duct, and iliac lymph node were measured; increases in CT values pre- to post-contrast were assessed as the contrast-enhanced index (CEI). Multi-detector row CT (MDCT) and volume rendering images showing the highest CEI were qualitatively evaluated. The CEI of all lymphatics peaked at 5–10 min. The mean CEI of TD at 10 min of group 2 (193.0 HU) and group 3 (201.5 HU) were significantly higher than that of group 1 (70.7 HU) (p = 0.024). The continuity and overall diagnostic acceptability of all lymphatic system components were better in group 3 (3.6 and 3.0, respectively) than group 1 (2.6 and 1.6) and group 2 (3.0 and 2.6) (p = 0.249 and 0.204). The optimal imaging protocol for intranodal DCCTL could be dual-phase imaging at 5 and 10 min after the injection of 300 mgI/mL iodinated contrast media. DCCTL provided good images of lymphatics and is potentially feasible in clinical settings. • Dynamic contrast-enhanced computed tomography lymphangiography with intranodal injection of water-soluble iodine contrast media showed the highest enhancement of all lymphatics at scan delays of 5 and 10 min. • The optimal iodine concentration for intranodal dynamic contrast-enhanced computed tomography lymphangiography might be 300 mgI/mL. • Intranodal dynamic contrast-enhanced computed tomography lymphangiography provided good images of all the lymphatic system components and is potentially feasible in clinical settings.

Purpose: To compare the diagnostic value of mono-exponential, bi-exponential, and stretched exponential diffusion-weighted imaging (DWI) for differentiating benign and malignant hepatic lesions. Methods: This prospective study was approved by our Institutional Review Board and the patients provided written informed consent. Magnetic resonance imaging was acquired for 56 patients with suspected liver disease. This identified 90 focal liver lesions with a maximum diameter >10 mm, of which 47 were benign and 43 were malignant. Using home-built software, two radiologists measured the DWI parameters of hepatic lesions for three models: the apparent diffusion coefficient (ADC) from a mono-exponential model; the true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) from a bi-exponential model; and the distributed diffusion coefficient (DDC) and water molecular diffusion heterogeneity index (α) from a stretched exponential model. The parameters were compared between benign and malignant hepatic lesions. Results: ADC, D, D*, f, and DDC values were significantly lower for malignant hepatic lesions than for benign lesions (P < 0.0001–0.03). Although logistic regression analysis demonstrated that DDC was the only statistically significant parameter for differentiating benign and malignant lesions (P = 0.039), however, the areas under the receiver operating characteristic curve for differentiating benign and malignant lesions were comparable between ADC (0.98) and DDC (0.98) values. Conclusion: DDC values obtained from the stretched exponential model could be also used as a quantitative imaging biomarker for differentiating benign and malignant hepatic lesions, however, the diagnostic performance was comparable with ADC values.

BackgroundAcute exacerbation of idiopathic interstitial pneumonias (AE-IIPs) induces permanent pulmonary dysfunction and is potentially lethal. The unpredictable occurrence of AE-IIPs remains an important clinical issue in the management of IIPs.MethodsIn this multicentre, retrospective, observational study, a predictive score for AE-IIPs was designed using clinical factors based on multivariate Fine–Gray analysis in patients with IIPs.ResultsBased on multivariate Fine–Gray analysis in an exploratory cohort of 487 patients with IIPs, the predictive score for AE-IIPs was determined as follows: 1 point each was added for honeycombing on high-resolution computed tomography (H), age >75 years (A) and lactate dehydrogenase level >222 U·L−1(L); the total score ranged from 0 to 3 (HAL score). The HAL score discriminated the risk of AE-IIPs with a C-index of 0.62 (95% CI 0.56–0.67); this discrimination was verified in a validation cohort of 402 patients with IIPs with a C-index of 0.67 (95% CI 0.60–0.73). In a combined cohort, the estimated cumulative risks for AE-IIPs at 1, 2, 3, 5 and 10 years were 1.9%, 3.5%, 5.1%, 7.7% and 12.9%, respectively, in the total score 0 group; 4.7%, 8.3%, 12.0%, 17.7% and 28.4%, respectively, in the total score 1 group; and 8.0%, 14.2%, 19.7%, 28.7% and 43.0%, respectively, in the total score ≥2 group. Subgroup analysis revealed that the HAL score was applicable to patients with and without idiopathic pulmonary fibrosis.ConclusionsThe HAL score discriminated the risk of AE-IIPs and could aid in the management of IIPs.

To evaluate the correlation between HeF obtained from gadoxetic acid-enhanced MR imaging and clinical biomarkers for the assessment of liver function. This prospective study was approved by our Institutional Review Board, and written informed consent was obtained from the patients. We recruited 48 patients carrying a known or suspected liver disease to undergo gadoxetic acid-enhanced MR imaging. The new model of the HeF was calculated from ΔR1 values of the liver and spleen. The HeF, quantitative liver-to-spleen contrast ratio (Q-LSC), and ΔT1 value (the reduction rate of the T1 value between the pre- and post-contrast images) were compared with the Child–Pugh and end-stage liver disease (MELD) scores. Among 48 patients, 40 were in Child–Pugh class A and 8 were in class B. The median HeF (P = 0.0001), Q-LSC (P = 0.015), and ΔT1 value (P = 0.0023) in patients in Child–Pugh class A were significantly higher than those in class B. The sensitivities, specificities, and area under the receiver-operating-characteristic curves for differentiating Child–Pugh class A and B were 95.0%, 87.5%, and 0.93 in the HeF; 77.5%, 75.0%, and 0.78 in the Q-LSC; and 57.5%, 100.0%, and 0.84 in the ΔT1 value, respectively. The HeF was significantly correlated with Child–Pugh (r = − 0.58, P

To acknowledge the facts of gadoxetate disodium-related events in Japan and to achieve better MR practice by analyzing large cohort data with various MR parameters. This prospective multi-institutional study included 1993 patients (1201 men, mean age 66.4 ± 12.8 years), who received dynamic MRI with gadoxetate disodium (gadoxetate group, n = 1646) or extracellular gadolinium-based contrast agents (other-GBCAs group, n = 347) between January and November 2016. Recorded data covered adverse reactions including dyspnea, breath-hold failure during acquisition, respiratory artifacts rated with a four-point scale, and MR parameters. We compared data between the two groups in whole cohort and age-, gender-, and institution-matched subcohort using χ2 test (n = 640). Logistic regression model was used to reveal independent associates of substantial artifacts in arterial phase imaging. Transient dyspnea rarely occurred in gadoxetate or other-GBCAs group (both

To evaluate the feasibility of optimized integrated combination of compressed sensing and parallel imaging technique (prototype Compressed SENSE) in gadoxetic acid-enhanced dynamic magnetic resonance (MR) imaging.Sixty-one patients underwent gadoxetic acid-enhanced dynamic imaging using enhanced T1 high-resolution isotropic volume excitation (eTHRIVE) with the Compressed SENSE (CS-eTHRIVE; C SENSE factor, 3.4; acquisition time, 10 s). Results were compared with 61 propensity score-matched patients who underwent conventional eTHRIVE (eTHRIVE; acquisition time, 20 s). For quantitative image analyses, signal intensity ratio (SIR) and signal-to-noise ratio (SNR), coefficient of variation (CV) of liver parenchyma were calculated in each dynamic phase. For qualitative image analyses, two radiologists rated the homogeneity of liver parenchyma, sharpness of liver edge and left external lobe, motion artifacts, and overall image quality in each dynamic phase using a five-point scale.SIRs of liver parenchyma with CS-eTHRIVE were significantly higher than with eTHRIVE in the hepatic arterial phase (HAP) (1.70 vs. 1.52) and transitional phase (TP) (2.18 vs. 2.06) (P ≤ 0.030). SNR of liver parenchyma were comparable between the two sequences in all phases. CV of liver parenchyma in HAP with eTHRIVE (0.079) was significantly higher than with CS-eTHRIVE (0.065) (P 0.001). Motion artifacts were significantly reduced with CS-eTHRIVE compared with eTHRIVE in all phases (P ≤ 0.005). The appearance ratio of extensive motion artifacts in HAP with CS-eTHRIVE (0/61; 0%) were significantly reduced compared with eTHRIVE (4/61; 6.6%) (P = 0.042). Overall image quality with CS-eTHRIVE was significantly better than with eTHRIVE in all phases (P ≤ 0.039).CS-eTHRIVE compared with eTHRIVE effectively reduced the acquisition time and extensive motion artifacts without degradation of image quality.

To assess if intravoxel incoherent motion (IVIM) imaging can be used to predict early response to chemoradiotherapy (CRT) in cervical cancer. IVIM imaging before and during CRT (at doses of 20 and 40 Gy) was performed in 17 patients with cervical squamous cell carcinoma. The percentage changes of IVIM parameters were significantly higher for complete remission (CR) than non-CR groups. IVIM may play a supplementary role for predicting early response to CRT in cervical cancer.

PURPOSE To compare four free-breathing scan techniques for gadoxetic acid-enhanced hepatobiliary phase imaging with conventional breath-hold scans. MATERIALS AND METHODS Gadoxetic acid-enhanced hepatobiliary phase imaging with six image acquisition sets performed in 50 patients. Image acquisition sets included fat-suppressed 3D T1-weighted turbo field echo with free-breathing pseudo-golden-angle radial stack-of-stars (FBRS) acquisition, FBRS with track (FBRST), FBRS with gate and track (FBRSG&T), thin-slice FBRS with gate and track (thin-slice FBRSG&T), free-breathing Cartesian acquisition (CartesianFB), and breath-hold Cartesian acquisition (CartesianBH). Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and image quality compared to the six-image acquisition sets. RESULTS Signal-to-noise ratio and CNR were significantly higher in FBRS, FBRST, FBRSG&T, and thin-slice FBRSG&T than in CartesianFB and CartesianBH (P < 0.001). Based on sharpness, motion artifacts, visibility of intrahepatic vessels, and overall image quality, thin-slice FBRSG&T had the highest image quality followed by CartesianBH and FBRSG&T (P < 0.001). Severe motion artifacts were observed in 25 patients in CartesianFB and three patients in CartesianBH, whereas image quality remained above the acceptable range in FBRSG&T, FBRST, FBRS, and thin-slice FBRSG&T in all cases. CONCLUSION Thin-slice FBRSG&T demonstrated excellent image quality compared with conventional CartesianBH in gadoxetic acid-enhanced hepatobiliary phase imaging. It can be apply to supplemental sequences of patients with unstable breath holding.

To evaluate the diagnostic performance of MRI-based radiomics model for differentiating phyllodes tumors of the breast from fibroadenomas.This retrospective study included 88 patients (32 with phyllodes tumors and 56 with fibroadenomas) who underwent MRI. Radiomic features were extracted from T2-weighted image, pre-contrast T1-weighted image, and the first-phase and late-phase dynamic contrast-enhanced MRIs. To create stable machine learning models and balanced classes, data augmentation was performed. A least absolute shrinkage and selection operator (LASSO) regression was performed to select features and build the radiomics model. A radiological model was constructed from conventional MRI features evaluated by radiologists. A combined model was constructed using both radiomics features and radiological features. Machine learning classifications were done using support vector machine, extreme gradient boosting, and random forest. The area under the receiver operating characteristic (ROC) curve (AUC) was computed to assess the performance of each model.Among 1070 features, the LASSO logistic regression selected 35 features. Among three machine learning classifiers, support vector machine had the best performance. Compared to the radiological model (AUC: 0.77 ± 0.11), the radiomics model (AUC: 0.96 ± 0.04) and combined model (0.97 ± 0.03) had significantly improved AUC values (both p 0.01) in the validation set. The combined model had a relatively higher AUC than that of the radiomics model in the validation set, but this was not significantly different (p = 0.391).Radiomics analysis based on MRI showed promise for discriminating phyllodes tumors from fibroadenomas.• The radiomics model and the combined model were superior to the radiological model for differentiating phyllodes tumors from fibroadenomas. • The SVM classifier performed best in the current study. • MRI-based radiomics model could help accurately differentiate phyllodes tumors from fibroadenomas.

We report a time-domain reflectance diffuse optical tomography (TD-RDOT) system for providing three-dimensional images of hemoglobin concentration, tissue oxygen saturation, water and lipid contents of breast cancer from reflectance measurements. A scan area of 5×5 grid points with a 10-mm spacing is marked on the breast surface so that the tumor is just below the center of the area. The breast scan is performed by measuring the temporal profiles of six wavelengths at each grid point using a time-domain diffuse optical spectroscopy (TD-DOS) system and a hand-held probe. The TD-DOS system that we developed is capable of measuring water and lipid contents and hemoglobin concentration. The hand-held probe is designed to measure the breast in reflectance mode with a source-to-detector separation of 20 mm. The three-dimensional distributions of the tissue parameters are restored using an iterative image reconstruction method. As a preliminary clinical demonstration, a breast cancer patient with a tumor size of approximately 20 mm was examined with the TD-RDOT. The reconstructed images show that the breast cancer had high hemoglobin concentration and water content, and low tissue oxygen saturation and lipid content. The results indicate that the TD-RDOT system has the potential to provide diagnostically relevant information on the tissue characteristics of the tumor at the bedside., Event: SPIE BiOS, 2021, Online OnlySPIE Photonics West

Iodine-131 (I-131) radioactive iodine therapy (RAI) after total thyroidectomy is the standard treatment for patients with differentiated thyroid cancer (DTC). We investigated the relationship between the quantitative parameters of the iodine uptake and the disappearance of the accumulation in the thyroid bed in adjuvant therapy using a 1.11 GBq or 3.70 GBq dose of I-131. We retrospectively analyzed the cases of 40 patients with DTC who were treated with RAI at our institution between April 2017 and August 2019. The patients were treated with the I-131 dose of 1.11 GBq (n = 25) or 3.70 GBq (n = 15) after total thyroidectomy. The I-131 whole-body scan and hybrid single-photon emission computed tomography/X-ray computed tomography (SPECT/CT) were performed 3 days after RAI. Using image analysis software, we measured the standardized uptake value (SUV) and absolute radioactivity concentration (kBq/ml) on the target lesions with the highest uptake in the thyroid bed. The median period from RAI to the evaluation of the absence of uptake of the thyroid bed was 6.75 months. After RAI, uptake of the thyroid bed disappeared in 26 of the 40 patients. The disappearance rate was significantly higher in the 3.70 GBq group than in the 1.11 GBq group (86.7% vs. 52.0%, respectively; p = 0.029). However, there were no significant differences in the values of kBq/ml or SUV between the 1.11 GBq group and 3.70 GBq group. On the other hand, the group in which the uptake disappeared after RAI showed significantly higher kBq/ml max and kBq/ml mean values than the group in which the uptake did not disappear after RAI (p = 0.028, p = 0.032, respectively). The SUVmax and SUVmean also tended to be higher in the disappeared-uptake group than the not-disappeared-uptake group, but the differences were not significant (p = 0.166, p = 0.176, respectively). The quantitative evaluation might be useful as one of the predictive indicators of the disappearance of the accumulation of radioactive iodine in the thyroid bed.

To evaluate pancreatic T1 mapping and extracellular volume (ECV) fraction’s feasibility to assess impaired glucose tolerance (IGT) patients. A total of 45 consecutive patients with known or suspected pancreatic disease underwent contrast-enhanced magnetic resonance (MR) imaging, including T1 mapping, using saturation recovery sequence. Patients were classified into three groups based on the American Diabetes Association criteria: no-diabetes subjects, HbA1c

The objective of this study was to evaluate the feasibility of histographic analysis of iodine concentration (IC) and CT number on single-source dual-energy CT (DECT) to assess response to first-line chemotherapy in patients with pancreatic ductal adenocarcinoma (PDAC) who received first-line chemotherapy but not radiation therapy.This prospective study was approved by our institutional review board, and patients gave written informed consent. Sixty consecutive patients with PDAC undergoing first-line chemotherapy underwent DECT during the pancreatic parenchymatous phase (PPP) and the equilibrium phase (EP). The IC and CT number of PDAC were measured using PPP and EP iodine-based material decomposition and monochromatic images (65 keV), respectively. Histographic parameters for the IC and CT number of PDACs were obtained, and differences in mean IC (ΔIC) and CT number (ΔHU) between the PPP and the EP were calculated. These parameters were then compared between the response (partial response or stable disease) and nonresponse (progressive disease) groups.Among the histographic parameters, the kurtosis of IC during the PPP (p = 0.018) and ΔIC (p = 0.0004) were identified as significant for differentiating between the two groups. IC diagnostic factor was calculated using the following coefficients of logistic regression analysis: 0.52 - (1.45 × kurtosis of IC during PPP) + (0.69 × ΔIC). The sensitivity, specificity, and area under the ROC curve for differentiating between the two groups were 97.7%, 70.6%, and 0.889, respectively.The IC diagnostic factor is a potential biomarker for assessing chemotherapeutic response in patients with PDAC.

BACKGROUND Signal intensity on T1 -weighted images (T1 WI) is associated with pancreatic fibrosis and HbA1c levels. PURPOSE To evaluate the feasibility of the pancreatic T1 value for assessment of subjects with normal and impaired glucose tolerance (IGT). STUDY TYPE A prospective single-institution study. POPULATION In all, 95 consecutive patients with a known or suspected pancreatic disease. FIELD STRENGTH/SEQUENCES 3T/fast pancreatic T1 mapping using a modified Look-Locker sequence. ASSESSMENT Following the American Diabetes Association criteria, patients were classified into three groups, as follows: no-diabetes subject, HbA1c < 5.7%; prediabetes, 5.7% ≤ HbA1c < 6.5%; and type 2 diabetes mellitus (T2DM), HbA1c ≥ 6.5%. Pancreatic T1 value and signal intensity ratio (SIR = SIpancreas /SImuscle ) using T1 WI were compared with the HbA1c values. STATISTICAL TESTS Quantitative data were assessed with one-way analysis of variance, Fisher's and Mann-Whitney U tests, and receiver-operating characteristic analysis. RESULTS The pancreatic T1 value was significantly longer in T2DM than in no-diabetes and prediabetes subjects (P

To assess the reliability of a prototype automated supplying artery tracking software (ASATS) using multidetector-row CT (MDCT) images in emergent TAE. Consecutive 53 patients underwent 57 sessions of emergent TAE during 7 months. Twenty-one cases were excluded due to a lack of CT data (n = 12) or negative angiographic findings (n = 9). Remaining 34 sessions of TAE and MDCT images in 32 patients (mean age 62.9 years; age range 37–92 years) were enrolled. ASATS was retrospectively conducted for the identification of supplying arteries which were confirmed with angiography (automated method). Manual modification was added as needed (semi-automated method). Two observers independently reviewed the MDCT images to detect supplying arteries (manual method). Detectability of supplying artery and time to analysis were compared among the automated, semi-automated, and manual methods by both observers. A total of 64 bleeding sites were demonstrated on angiography. The detectability was 28 (43.8%) for automated method, 53 (82.8%) for semi-automated method, 55 (85.9%) for observer 1, and 58 (90.6%) for observer 2. Detectability of semi-automated method was significantly better than of automated method (P = 0.000) and comparable with manual method by both observers (P = 0.193 and 0.081). Average time to analysis was 185.4 s for automated method, 297.2 s for semi-automated method, 186.2 s for observer 1, and 243.7 s for observer 2. ASATS has a sufficient ability to identify supplying arteries of bleeding by adding manual modification as needed and can be used for emergent TAE. Level 4, Case Control Study.

The objective of our study was to assess the preoperative resectability of pancreatic ductal adenocarcinoma (PDAC) using the National Comprehensive Cancer Network (NCCN) guideline, the general rules of the Japan Pancreas Society (JPS), and both of them combined.Eighty-six consecutive patients with PDAC (50 men and 36 women; mean age ± SD, 70.8 ± 9.0 years; age range, 49-86 years) underwent dynamic contrast-enhanced CT. Following the NCCN guideline, the degree of vascular invasion was evaluated to determine the NCCN score: 0 points for absence of vascular invasion, 1 point for tumor contact ≤ 180°, and 2 points for tumor contact180°. Direct invasion to adjacent structures was rated according to the general rules of JPS to determine the JPS score: 0 points for absence and 1 point for presence. The NCCN score, JPS score, and sum of the two scores, which we refer to as the "combined score," were compared with histopathologic or intraoperative findings as well as for the differentiation of R0 resection (negative resection margins) from R1 (microscopic tumor infiltration) and R2 (macroscopic residual tumor) using ROC curve analysis.The sensitivities, specificities, and areas under the ROC curves (AUCs) for the differentiation of R0 from R1 and R2 were 100.0%, 40.0%, and 0.725, respectively, with the NCCN score; 63.9%, 84.0%, and 0.824 with the JPS score; and 86.9%, 68.0%, and 0.874 with the combined score. The AUC of the combined score was significantly greater than that of the NCCN score (p = 0.0059).The assessment of resectability of PDAC based on the combined criteria of the NCCN guideline and general rules of JPS was superior to that based on either criterion alone.

We aimed to evaluate the MR findings of the orbit in patients with Vogt–Koyanagi–Harada disease (VKHD). We included 14 patients with clinically diagnosed VKHD, who underwent orbital MR imaging before treatment between May 2011 and August 2017. The mean duration from initial symptom onset to MR imaging was 16 days (range, 2–36 days). Fat-suppressed gadolinium-enhanced T1-weighted images were obtained in six patients. We retrospectively assessed the choroids and Tenon’s capsules for the presence of thickening on unenhanced images and abnormal enhancement on contrast-enhanced images. Bilateral choroidal thickening was observed in 14 patients (100%) on T1-weighted images and in 12 patients (85.7%) on T2-weighted images. Choroidal thickening showed posterior pole predominance in 11 patients (78.6%) and diffusely distributed in the remaining three patients (21.4%). Bilateral Tenon’s capsule thickening was observed in five patients (35.7%) on T1-weighted images and in 14 patients (100%) on T2-weighted images. On contrast-enhanced images, the choroids and Tenon’s capsules were abnormally enhanced in six patients (100%). MR imaging sensitively detected abnormalities of the choroids and Tenon’s capsules in patients with VKHD. Bilaterality and predominant posterior pole distribution were characteristic of choroidal VKHD.

Background Simultaneous acquisition of magnetic resonance angiography (MRA) and diagnostic images is challenging in contrast-enhanced upper abdominal MRI. Purpose To evaluate the image quality of MRA of the abdomen acquired simultaneously with diagnostic MR images, and to compare the contrast effect, conspicuity of aortic branches, and pancreatic lesions in MRA between gadobutrol and gadoterate meglumine. Study type Prospective. Population Eighty-eight patients with known and suspected upper abdominal disease. Field strength/sequences 3T/4D-eTHRIVE (T1 -weighted fat-suppressed 3D fast gradient echo) for multiarterial phase imaging. Assessment The artery-to-muscle signal intensity ratio (SIR), conspicuity of aortic branches on the axial, maximum intensity projection (MIP), and volume-rendered (VR) images, and conspicuity of focal pancreatic lesions were compared between gadobutrol and gadoterate meglumine. The diameters of aortic branches were measured on axial MRA and computed tomography angiography (CTA) images and then compared. Statistical tests Quantitative and qualitative data were assessed with the Mann-Whitney U-test. The diameters of aortic branches between MRA and CTA were compared with a Spearman rank correlation test. Results View-sharing multiarterial phase imaging was successfully performed in all patients. The SIRs of common hepatic artery (P = 0.0051) and left renal artery (RA) (P = 0.045), vascular conspicuities of right and left hepatic arteries (P = 0.010 and 0.030) and right and left RAs on axial (P = 0.0065 and 0.036), and that of gastroduodenal artery on MIP (P = 0.039) with gadobutrol were significantly higher than those with gadoterate meglumine. The conspicuity of focal pancreatic lesions were comparable between the gadobutrol and gadoterate meglumine (P = 0.73). The vascular diameters on MRA and CTA were strongly correlated in all aortic branches (r = 0.842-0.942, P Data conclusion High-quality MRA of the abdomen was obtained simultaneously with the diagnostic MR images using view-sharing multiarterial phase imaging that also demonstrated comparable image quality between gadobutrol and gadoterate meglumine. Level of evidence 2 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2017.

Purpose To evaluate the value of view-sharing multi-hepatic arterial-phase (mHAP) imaging for diagnosis of hypervascular hepatocellular carcinoma (HCC). Materials and methods Forty-seven consecutive patients with HCC underwent gadoxetic acid-enhanced magnetic resonance (MR) imaging before angiographic and lipiodol CT. Hepatic arterial-phase images were obtained at 5 consecutive phases with shared central k-space of 25%, followed by portal venous, late (2 and 3 min), and hepatobiliary phase imaging. One-hundred-eight HCC nodules (size: 5–88 mm, mean size: 18.2 mm) confirmed on angiographic CT and lipiodol CT were evaluated for LI-RADS category and compared with single arterial-phase and mHAP findings regarding wash out, capsule, corona enhancement, and image quality. Results Twenty-four HCCs (22.2%) (size: 6–19 mm, mean size: 12.3 mm) were categorized as LR-3 based on the single arterial-phase. Capsule appearance (25.9%) and washout (57.4%) were most frequently observed in late phase (2 min). Corona enhancement was observed in 73.1% of all HCCs on mHAP. For the 24 HCCs of LR-3, corona enhancement was observed in 75% on mHAP and contributed to upgrade category. No significant difference was found in the frequency of corona enhancement between mHAP and angiographic CT ( P = 0.11). Image quality was valued as good or excellent in all cases. Conclusion View-sharing mHAP was feasible without compromising image quality and contributed to the improvement in diagnostic confidence for hypervascular HCC in gadoxetic acid-enhance MR imaging.

Purpose To compare diagnostic performance of unenhanced and CTA images (Image set 1) to that of combined unenhanced, CTA, and venous-phase images (Image set 2) for incidentalomas in patients with aortic aneurysm. Methods Preoperative CT Images of consecutive 240 patients were reviewed by two observers for incidentalomas. Diagnostic performance was assessed. Results Sensitivity was higher in Image set 2 than Image set 1 in observer 1 and overall (P = 0.03 and 0.00). AUCs for both observers were higher in Image set 2 than Image set 1 (P = 0.03 and 0.01). Conclusion Addition of venous-phase to CTA significantly improved diagnostic performance of incidentalomas.

Objectives Conventional evaluation of anti-tumor activity on the basis of tumor size is inadequate for immune checkpoint inhibitors (ICIs). We therefore aimed to assess the usefulness of intravoxel incoherent motion magnetic resonance imaging (IVIM-MRI) for evaluation of the therapeutic efficacy of ICIs. Materials and methods A chest IVIM-MRI was performed before and 2, 4, and 8 weeks after administration of ICIs in patients with advanced non-small-cell lung cancer. Apparent diffusion coefficient (ADC), skewness of ADC (ADCskew), kurtosis of ADC (ADCkurt), true diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) were evaluated at each evaluation point and changes from the baseline (Δ). Results Twenty patients were enrolled in this study. An increased ADC 8 weeks and decreased ADCkurt and ΔADCkurt 4 weeks after ICIs was associated with objective responses and longer progression-free survival (PFS). A decreased ΔADCskew at 4 weeks was associated with objective responses, disease control, and longer PFS and overall survival. There was no correlation between the efficacy of ICIs and D, D* and f. All of three patients who had pseudoprogression had decreased ΔADCskew at 4 weeks and two of them had decreased ΔADCkurt at 4 weeks. Inversely, all five patients who had progressive disease (PD) did not have increased ΔADCskew at 4 weeks and only one of them had decreased ΔADCkurt at 4 weeks. Conclusions Changes in histograms of ADC may be useful for predicting long-term efficacy and distinguishing between pseudoprogression and actual PD after ICIs.

Purpose To investigate iodine dose concentration required for adequate hepatic parenchymal enhancement on fast-kilovoltage-switching dual-energy computed tomography (DECT) of the abdomen based on patient body weight. Materials and methods The protocol of this prospective study was approved by the local Institutional Review Board and written informed consent for study participation was obtained from all patients. The study cohort of 204 consecutive patients who underwent whole body single-source DECT to screen for tumor metastases and/or recurrence after surgical resection of malignant tumors were randomly assigned to one of three protocols according to the iodine dose (400, 500, and 600 mgI/kg). For each case, two radiologists quantitatively and qualitatively reviewed three energy levels (65, 70, and 75 kilo electron volt [keV]) of the portal venous phase virtual monochromatic images (VMIs). CT numbers of the liver and the qualitative hepatic parenchymal enhancement were compared among the VMIs with the three protocols and three energy levels. Results Hepatic enhancement (ΔHU > 50HU) was achieved at 65 keV with 400, 500, and 600 mgI/kg, at 70 keV with 500 and 600 mgI/kg, and at 75 keV with 600 mgI/kg. The hepatic parenchymal enhancement was graded as sufficient hepatic enhancement in 97%, 100%, and 99% at 65 keV with 400, 500, and 600 mgI/kg, 88% and 97% at 70 keV with 500 and 600 mgI/kg, and 84% at 75 keV with 600 mgI/kg, respectively. Conclusion The iodine dose can be reduced to 400 mgI/kg at 65 keV or 500 mgI/kg at 70 keV in DECT without compromising hepatic parenchymal enhancement.