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Please see the Editorial Comment by Brian M. Haas discussing this article. BACKGROUND. Acute exacerbation (AE) is a life-threatening complication of inter-stitial pneumonia (IP). Thoracic surgery m...

Purpose Detecting bladder cancer (BC) in routine CT images is important but is sometimes difficult when cancer is small. We evaluated the ability of 40-keV advanced monoenergetic images to depict BC. Materials and methods Fifty-two patients with a median age of 74 years (range 45–92) who were diagnosed as BC with transurethral resection or cystectomy, were included. They were examined with contrast-enhanced dual-energy CT (DE-CT) and advanced virtual monoenergetic images (40 keV) were reconstructed. For evaluating depictability of BC on 40-keV or virtual-120-kVp images, the difference in CT number between the cancer and bladder wall (BC–BW value) were calculated. We also subjectively assessed depictability of BC in virtual-120-kVp and 40-keV images using a 4-grade Likert scale (3: clear, 0: not visualized). Results In 42 of 52 patients, BC–BW values could be calculated because BC was detected on CT images. The mean BC–BW value at 40 keV was significantly higher than that of virtual 120 kVp [80.5 ± 54 (SD) vs. 11.4 ± 12.5 HU, P P Conclusion The advanced monoenergetic reconstruction technique reconstructed using DE-CT image is useful to depict BC.

We prospectively evaluated thin-slice coronal turbo spin-echo (TSE) diffusion-weighted imaging (DWI) covering a larger area with the recently-developed techniques on a 3T MRI scanner, compared with echo-planar imaging (EPI)-DWI in patients undergoing routine hand MRI. Visual score assessment and apparent diffusion coefficient (ADC) measurement were performed for patients with suspected hand tumors. TSE-DWI was superior to EPI-DWI, with less image distortion. The visual score and ADC comparison assessments proved that the image noise of TSE-DWI was acceptable.

BACKGROUND AND PURPOSE: The signal intensity of the thyroid in neonates is high on T1WI. It is affected by gestational and postnatal ages. However, the extent of the influence of these ages is unknown. This study investigated the relationship of signal intensities of the infant thyroid with postnatal and gestational ages and anterior pituitary using 3D gradient-echo T1WI. MATERIALS AND METHODS: This retrospective study included 183 T1-weighted images from 181 infants. Using a multiple linear regression analysis, we evaluated the effects of postnatal and gestational ages on the thyroid–muscle signal intensity ratio. The relationship between the thyroid and anterior pituitary signal intensities on T1WI and the age of the infants was evaluated. RESULTS: Multiple linear regression analysis showed that the thyroid signal intensity was affected negatively by postnatal age at examination and positively by gestational age at birth (P < .01 and P = .04, respectively). According to the standardized partial regression coefficients, the influence of postnatal age at examination was stronger than that of gestational age at birth (−0.72 and 0.13, respectively). The thyroid and anterior pituitary signal intensities reached constant values at 12 weeks' postnatal age, and the mean thyroid–anterior pituitary signal intensity ratios were almost 1 throughout the entire period. CONCLUSIONS: The signal intensity of the infant thyroid on T1WI was more strongly influenced by the postnatal age at examination than the gestational age at birth, and it was almost equal to that of the anterior pituitary.

To evaluate the usefulness of the advanced monoenergetic imaging (AMI) reconstruction technique for dual-energy computed tomography to evaluate endoleaks after endovascular stent-graft placement. Ninety-five dual-phase (early and delayed phases) enhanced CT examinations were performed for 60 patients who underwent endovascular stent-graft placement. AM images were reconstructed at 40 keV and compared with the standard 120-kVp images (SI). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of the aorta and endoleak were measured. Two radiologists subjectively assessed endoleak delineation and contrast enhancement conditions using a 5-point Likert scale (1: poor—5: excellent). Mean SNRs of the aorta were higher by AMI (early; 34.7 ± 10.2 [SD], delay; 11.4 ± 3.2) than by SI (early; 23.1 ± 6.3, delay; 8.6 ± 2.2) (P

An 11-year-old male was admitted to our hospital with the acute exacerbation of chronic heart failure. A peripherally inserted central catheter (PICC) was inserted from the left forearm. Ten days after its insertion, the withdrawal of PICC was attempted because of occlusion. However, it was not possible to remove PICC because a fibrin sheath had attached around its tip. A color Doppler and probe compression technique revealed the presence of a fibrin sheath, which could not be detected by gray-scale (real-time B-mode) ultrasonography. This case demonstrated that the color Doppler and probe compression technique is useful for detecting a fibrin sheath. Keywords: Peripherally inserted central catheter, Fibrin sheath, Ultrasonography, Probe compression technique

Distinguishing between focal atelectasis (FA) and pleural dissemination (PD) is important for determining the optimal therapeutic strategy for thymic epithelial tumors (TET). This study aimed to identify useful computed tomography (CT) features for distinguishing between these two conditions.We retrospectively analyzed preoperative CT images of 27 TET, which included 40 PD and 40 FA lesions. Two radiologists independently interpreted the pleural lesions without knowing the final diagnosis. The CT images were evaluated to assess the lesion location, size, and shape, presence of a spinous shadow and ground glass opacities (GGO) near to the lesion, and the shortest distance from the lesion to the nearest peripheral pulmonary artery (PA).FA lesions tended to occur on the dorsal side (90%, P = 0.024); have shorter major and minor axes (P 0.001), a triangular shape (43%, P = 0.002), a spinous shadow (45%, P = 0.001) and GGO (28%, P = 0.006); and be close to a peripheral PA (P = 0.007). Ninety percent of PD lesions were located in the left thorax, and all of them were ipsilateral to the tumor (both P 0.001). The 9 examined factors exhibited sensitivity, specificity, positive predictive, and negative predictive values of 85%, 95%, 94%, and 86%, respectively, for diagnosing FA (when ≥3 factors were present), and 90%, 48%, 63%, and 83%, respectively, for diagnosing PD (when ≥4 factors were present).The site, size, and shape of a lesion; the presence of a spinous shadow/GGO; and the distance to the nearest PA are useful for distinguishing between PD and FA.

Children with congenital heart diseases (CHDs) may need to be followed up with contrast-enhanced CT following the Fontan operation because complications such as the occlusion of conduits may occur. The purpose of the present study was to develop an adequate contrast-enhanced CT protocol for children with CHD following the Fontan operation. Between July 2012 and July 2017, 29 CT examinations for 26 patients aged 2–11 years (median 5 years) with CHD following the Fontan operation were performed using dual-source CT. A non-ionized contrast medium was injected through the dorsum manus vein. Scanning began 60 or 70 s after the start of the injection. The delayed phase was randomly selected to be 60 s in 14 cases and 70 s in 15 cases. We evaluated the enhancement of conduits following the Fontan operation at delayed phases. The CT numbers of conduits at 60 and 70 s were 185 ± 46 and 185 ± 31 HU, respectively (P = 0.97). In contrast-enhanced CT for children after the Fontan operation, both of the delayed phases (60 and 70 s) appeared to be adequate for evaluating intraconduit patency.

Calcifying aponeurotic fibroma (CAF) is a rare benign tumor that typically develops in the fascia and tendons. On MRI, CAF usually shows isointensity on T1WI and heterogeneous high intensity on T2WI. We report a case of 17-month-old girl with CAF on her right ankle. MRI showed an usual signal intensity for CAF. At 3 years and 4 months of age, MRI revealed hyperintense nodules on T1WI and T2WI inside of the CAF. These fatty areas corresponded to coarse calcified nodules on CT. Radiologists should be aware of the fact that fat-like signals can appear in CAF on MRI.

A 6-year-old girl was admitted to our hospital due to discharging the strobila of a tapeworm (Diphyllobothrium nihonkaiense) from her anus. Before excreting the tapeworm completely with anthelmintics, ultrasonography was performed. The tapeworm was shown as a slightly high echoic strand-like lesion on ultrasonography in the terminal ileum. In this strand-like lesion, some high echoic spots were detected. This finding was considered as a characteristic of Diphylloborthriasis. Keywords: Ultrasonography, Diphyllobothrium nihonkaiense, Pediatric

This short report clarifies the heterogeneity of structural magnetic resonance imaging (MRI) findings in seven demented patients due to pathologically accumulated TAR DNA-binding protein-43 (TDP-43) protein using visual analyses including visual rating scales (i.e., global cortical atrophy and medial temporal atrophy scales). In addition to the well-known frontotemporal lobar atrophy, structural MRI has revealed multifaceted imaging findings including asymmetric atrophy of the frontoparietal lobe and cerebral peduncle, midbrain atrophy, and localized or diffuse white matter T2 hyperintensity. Understanding of these multifaceted neuroimaging findings is important for the precise antemortem diagnosis of TDP-43 proteinopathy.

BackgroundIn adrenal vein sampling, selecting the right adrenal vein is technically difficult and it is important to evaluate the right adrenal vein anatomy before adrenal vein sampling. The advanced monoenergetic reconstruction technique has recently become available and we hypothesized that this technique may be useful.PurposeTo evaluate the usefulness of the advanced monoenergetic reconstruction technique in dual-energy computed tomography (CT; advanced monoenergetic images) for evaluation of vascular anatomy before adrenal vein sampling.Material and MethodsTwenty-one patients underwent three-phase (20, 30, and 70 s) contrast-enhanced CT before adrenal vein sampling. Advanced monoenergetic images were reconstructed at 40 keV and analyzed objectively and subjectively in comparison with the standard 120-kVp images. As objective evaluation, the signal-to-noise ratio and contrast-to-noise ratio of the right adrenal vein were assessed. As subjective evaluation, two radiologists assessed the delineation of the right adrenal vein using a 5-point Likert scale (1 = poor, 5 = excellent). Furthermore, the technical success rate of adrenal vein sampling and procedure time were also evaluated.ResultsThere was no difference in the signal-to-noise ratio between the two groups. The contrast-to-noise ratios of the right adrenal vein of advanced monoenergetic images were higher than those of the standard images ( P ConclusionAdvanced monoenergetic imaging appears to be useful in the delineation of the right adrenal vein before adrenal vein sampling.

The purpose of this study is to clarify the characteristic structural magnetic resonance imaging (MRI) findings in demented patients with pathologically confirmed argyrophilic grain disease (AGD). Nine pathologically confirmed AGD patients with cerebral three-dimensional T1-weighted MRI were evaluated in this study. In addition to visual rating scales of atrophic and asymmetric changes in the limbic and temporal lobes, voxel-based morphometry (VBM) was performed to assess group difference between pathologically confirmed AGD and Alzheimer’s disease (AD) patients. On visual analyses of AGD patients, the medial temporal, anterior temporal, and posterior temporal atrophy scores were 3.3 ± 0.7, 1.7 ± 0.5, and 1.0 ± 0.7, respectively. Asymmetric scores of the hippocampus and parahippocampal gyrus, amygdala and ambient gyrus, anterior temporal, and posterior temporal lobes were rated as 1.1 ± 0.7, 1.6 ± 0.5, 1.3 ± 0.8, and 0.4 ± 0.7, respectively. In spite of no statistical differences in atrophic scores, AGD patients showed the higher score and proportion of anterior temporal asymmetric score than AD (p = 0.03 and 0.02). Compared with controls, VBM analysis revealed left dominant asymmetric atrophy predominantly in the limbic and anterior temporal lobe in AGD patients. By contrast, there was no significant gray matter reduction between AGD and AD patients. Asymmetric atrophy relatively localized to the anterior temporal and limbic lobes including the amygdala and ambient gyrus is a characteristic MRI finding of AGD. For the precise antemortem diagnosis, especially to differentiation from AD, it is important to pay attention to this asymmetric change.

Background Thymoma exhibits a range of histological and biological features and their imaging findings varies. Purpose To evaluate the associations between CT findings of thymomas and their classification according to the Masaoka staging system and World Health Organization (WHO) classification. Material and Methods Eighty-four patients with thymoma were evaluated. Comparisons between the CT findings of Masaoka stage I/II and III/IV lesions, and the WHO type A-B1 (low risk) and B2/B3 (high risk) lesions were performed. Results Stage III/IV thymomas (mean size, 60 mm) were significantly larger than stage I/II (45 mm) lesions and had more irregular shape and contour. Necrosis and calcification were observed in 16 (59%) and nine (33%) stage III/IV thymomas, and 16 (28%) and seven (12%) stage I/II lesions, respectively. Regarding the WHO classification, the high-risk thymomas displayed irregular shape and contour more often than low-risk lesions. There were significant differences between the patterns of mediastinal invasion seen in high- and low-risk groups; 21 (68%) vs. six (12%) lesions demonstrated mediastinal fat invasion, seven (23%) vs. two (4%) lesions exhibited great vessel invasion, five (16%) vs. 0 (0%) lesions displayed pericardial invasion, and 18 (58%) vs. 10 (20%) lesions invaded the lungs, respectively. Conclusion Masaoka stage III/IV thymomas were larger in size, had more irregular shape and contour, and exhibited necrosis and calcification more often than the stage I/II lesions. In the WHO classification, high-risk thymomas demonstrated more irregular shape and contour than low-risk thymomas.

Purpose Various magnetic resonance imaging (MRI) techniques including T2*-weighted imaging, susceptibility-weighted imaging, and MR relaxometry had been performed to evaluate different patterns of brain iron depositions in Parkinsonian syndrome. The aim of the present study was to evaluate the diagnostic value of a volume of interest (VOI) analysis on the principles of echo shifting with a train of observations (PRESTO) imaging using the statistical parametric mapping (SPM) 8 and the WFU PickAtlas program for the diagnosis of Parkinsonian syndrome.,Methods: Fifty subjects, including 13 with the Parkinsonian variant of multiple system atrophy (MSA-P), 12 with progressive supranuclear palsy (PSP), 12 with Parkinson's disease (PD) and 13 controls were evaluated in this study. After the spatial normalization of PRESTO images on SPM8, the WFU PickAtlas program was performed to create target VOIs in the putamen, red nucleus, substantia nigra, subthalamic nucleus, and dentate nucleus. The signal intensity ratio (SIR) was calculated by normalizing the signal of each VOI to that of the cerebrospinal fluid space. These SIRs were used as determinants in receiver operating characteristic (ROC) analyses. Results SIR of the putamen was significantly lower in MSA-P than in PSP (P = 0.0051) and controls (P = 0.0004). In contrast, SIR of the red nucleus was significantly lower in PSP than in MSA-P (P = 0.0003), PD (P = 0.0029), and controls (P = 0.0011). In ROC analyses, SIR of the putamen exhibited the highest areas under the curves (AUCs) of 0.83 (vs. PSP) and 0.91 (vs. controls) in the diagnosis of MSA-P. On the other hand, SIR of the red nucleus exhibited the highest AUCs of 0.87 (vs. MSA-P), 0.90 (vs. PD), and 0.89 (vs. controls) in the diagnosis of PSP. Conclusions The VOI analysis based on spatially normalized PRESTO images may be useful for depicting hypointensity, indicative of abnormal iron depositions, of the putamen and red nucleus in the diagnosis of MSA-P and PSP.

Background Preoperative transcatheter arterial embolization for hypervascular bone and soft tissue tumors plays an important role in reducing intraoperative blood loss (IBL). Purpose To evaluate the use of a gelatin sponge in preoperative transcatheter arterial embolization for hypervascular bone and soft tissue tumors in the pelvis or extremities. Material and Methods Thirty-seven patients (21 men, 16 women; median age, 61 years; age range, 23–79 years) underwent preoperative transcatheter arterial embolization between April 2004 and January 2015. Medical records and images were reviewed, and the technical success rate, clinical success rate, and complications were evaluated. Technical success was defined as a devascularization rate of 75% or higher, and clinical success was defined as intraoperative blood loss (IBL) Results Tumor sizes were in the range of 2.0–13.0 cm (median, 5.0 cm). The devascularization rate was decreased by >75% at follow-up angiography in all cases, and the technical success rate was 100 % (37/37). The median IBL was 491 mL (range, 30–3800 mL), and the clinical success rate was 89% (33/37). The minor complication of local pain was observed in 13 out of 37 cases (35%) during or after embolization, but was controllable by an analgesic. Conclusion Preoperative transarterial embolization using a gelatin sponge appears to be feasible and safe, and may contribute to decreasing IBL.

To evaluate the efficacy and safety of transcatheter arterial embolization (TAE) for renal angiomyolipoma (AML) using a micro-balloon catheter and a mixture of ethanol and lipiodol. Twelve consecutive patients with 15 AMLs, 9 females and 3 males, with a median age of 44 years (range, 11–81), underwent this procedure between 2011 and 2016. In all procedures, a micro-balloon catheter was advanced to the feeding artery of the AML and TAE was performed with a mixture of ethanol and lipiodol under balloon inflation. We reviewed medical records and images, and evaluated the technical success rate, clinical success rate, and complications. Technical success was defined as completion of TAE using the micro-balloon catheter and the mixture of ethanol and lipiodol. Clinical success was defined as reduction of tumor size on CT, which was performed before and after TAE. In 14 of 15 AMLs, the micro-balloon catheter could be advanced to the feeding artery, and TAE was performed successfully. Thus, the technical success rate was 93%. Among these 14 AMLs of 11 patients, 13 AMLs of 10 patients could be followed and tumor shrinkage was confirmed in all. Thus, the clinical success rate was 100%. Four patients had mild symptoms after TAE; the minor complication rate was 33% (4/12), and the major complication rate was 0%. TAE for renal AML using the micro-balloon catheter and mixture of ethanol and lipiodol appears to be effective and safe.

Objective: The purpose of our study was to evaluate the visibility of the hilar lymph nodes (LNs) using advanced virtual monoenergetic low-keV images compared with early-phase contrast-enhanced CT. Methods: Dual energy contrast-enhanced CT was performed for pre-operative evaluation of lung cancer at 20 and 60 s after administration of contrast media in 50 patients (32 males and 18 females; mean age, 69 years). Five kinds of images (A: 20 s/120 kV; B: 60 s/40 keV; C: 60 s/50 keV; D: 60 s/120 kV; E: 60 s/100 kV) were reconstructed. We measured the CT number of the bilateral main pulmonary arteries (PAs), pulmonary veins (PVs) and hilar LNs, and evaluated the differences in CT number (Hounsfield units, HUs) between the PA/PV and LNs (PA–LN and PV–LN contrast). Artifacts from the superior vena cava (SVC) were also evaluated. Results: The mean PA–LN contrast (HU) was 415 in image group A, 299 in B, 180 in C, 80 in D, and 100 in E. The mean PV–LN contrasts in each group were 306, 287, 177, 78, and 99, respectively. Image group B showed the second highest PA–LN contrast following image group A. There was no significant difference in the PV–LN contrast between image groups A and B. The PA–LN and PV–LN contrasts of image groups B and C were significantly higher than those of E. SVC artifacts were lower in the delayed-phase images (Group B–E) than in Group A. Conclusion: To evaluate the hilar LNs with a single image series, advanced virtual monoenergetic 40-keV imaging at the delayed 60-s phase seems to be the most valuable. Advances in knowledge: Advanced virtual monoenergetic image is useful for evaluation of both hilar LNs and tumors in the delayed phase without artifact derived from the streak artifact from dense contrast media in the SVC.

Recently, it has been recognized that pathologically proven progressive supranuclear palsy (PSP) cases are classified into various clinical subtypes with non-uniform symptoms and imaging findings. This article reviews essential imaging findings, general information, and advanced magnetic resonance imaging (MRI) techniques for PSP and presents these MRI findings of pathologically proven typical and atypical PSP cases for educational purposes. With the review of literatures, notably including atypical pathologically proven PSP cases, MRI and clinical information of 15 pathologically proven typical and atypical PSP cases were retrospectively evaluated. In addition to typical symptoms, PSP patients can exhibit atypical symptoms including levodopa-responsive parkinsonism, pure akinesia, non-fluent aphasia, corticobasal syndrome, and predominant cerebellar ataxia. As well as clinical symptoms, the degree of midbrain atrophy, a well-known imaging hallmark, is not consistent in atypical PSP cases. This fact has important implications for the limitation of midbrain atrophy as a diagnostic imaging biomarker of PSP pathology. Additional evaluation of other imaging findings including various regional atrophies of the globus pallidus, frontal lobe, cerebral peduncle, and superior cerebellar peduncle is essential for the diagnosis of atypical PSP cases. It is necessary for radiologists to recognize the wide clinical and radiological spectra of typical and atypical PSP cases.

To assess the usefulness of transcatheter arterial embolization (TAE) for the hepatic arterial injury related to percutaneous transhepatic portal intervention (PTPI). Fifty-four patients, 32 males and 22 females with a median age of 68 years (range 43–82 years), underwent PTPI. The procedures consisted of 33 percutaneous transhepatic portal vein embolizations, 19 percutaneous transhepatic variceal embolizations, and 2 percutaneous transhepatic portal venous stent placements. Two patients with gastric varices underwent percutaneous transhepatic variceal embolization twice because of recurrence. Therefore, the total number of procedures was 56. Among them, hepatic arterial injury occurred in 6 PTPIs in 5 patients, and TAE was performed. We assessed technical success, complications related to TAE, and clinical outcome. Technical success was defined as the disappearance of findings due to hepatic arterial injury on digital subtraction angiography. As hepatic arterial injuries, 4 extravasations and 2 arterioportal shunts developed. All TAEs were performed successfully. The technical success rate was 100 %. Complication of TAE occurred in 5 of 6 TAEs; 3 were focal liver infarction, not requiring further treatment, and 2 were biloma that required percutaneous drainage. Five TAEs in 4 patients were performed immediately after the PTPI, and these 4 patients were alive. However, one TAE was performed 10 h later, and the patient died due to multiple organ failure 2 months later although TAE was successful. TAE is a useful treatment for hepatic arterial injury related to PTPI. However, it should be performed at an early stage.

Congenital abdominal wall defects include several entities such as gastroschisis, omphalocele, and cloacal exstrophy. It is important for perinatal management and parental counseling to understand the magnetic resonance (MR) imaging features essential for correctly diagnosing the clinical condition and predicting the prognosis of fetal patients. The purpose of this pictorial review is to demonstrate the MR imaging features of fetal cases with an abdominal wall defect and the pitfalls of image findings.

Background Transcatheter arterial chemoembolization (TACE) has been widely performed for inoperable hepatocellular carcinoma (HCC). Super-selective TACE is preferable to non-selective therapy and it is important to advance the catheter tip as close to the tumor as possible in the feeding artery. A new microcatheter with a 1.9-Fr non-tapered tip has recently become available and this new microcatheter can be inserted into a 2.7-Fr. microcatheter. It is called the triple co-axial (triaxial) system. Purpose To evaluate the clinical usefulness of super-selective TACE for HCC using the triaxial system. Material and Methods We evaluated 63 HCCs that underwent super-selective TACE. Requirements for inclusion in this study were: (a) HCCs 3 cm or less in diameter; (b) TACE performed by a single operator; and (c) no additional treatment in the absence of local progression. All patients were followed for more than 1 year after TACE. The median follow-up period for surviving patients was 20 months (range, 17–31 months). The conventional system was used in 35 HCCs (control group), and the triaxial system was used in 28 (triaxial group). We reviewed angiographies at TACE and follow-up CT, and then evaluated local tumor status in the two groups. Results Local tumor control rates at 3, 6, and 18 months were 64%, 36%, and 29%, respectively, in the triaxial group, and 40%, 14%, and 8.6%, respectively, in the control group ( P = 0.0086). There were no major complications in either group. Conclusion The triaxial system appears to be useful for super-selective TACE and may contribute to achieving higher local control rates for HCC.

Background: The accuracy of 18F-2-deoxy-fluoro-D-glucose positron emission tomography (FDG-PET) for diagnosing nodal status in patients with lung cancer was initially reported as excellent, but, with increasing experience, the problem of false-positive and false-negative assessments has been observed. Purpose: To evaluate the accuracy of FDG-PET for diagnosing nodal status in lung cancer patients with pathologically proven N2 lymph nodes and compare it with that of computed tomography (CT). Material and Methods: Nineteen pN2 patients (13 males and six females) with primary lung cancer undergoing preoperative CT and FDG-PET were investigated. Lymph nodes were considered to be positive when uptake higher than the surrounding mediastinal level was visually observed. Slight symmetrical mediastinal uptake was considered to be negative, representing benign physiological accumulation. Radiological and pathological correlation was investigated, and the association between FDG accumulation and the size of metastatic lymph nodes and metastatic lesions was evaluated. Results: Of the 19 patients, nodal stage determined by using FDG-PET was cN0 in four (21%) cases, cN1 in three (16%), cN2 in nine (47%), and cN3 in three (16%). On CT, nodal stage was cN0 in three (16%) cases, cN1 in seven (37%), cN2 in eight (42%), and cN3 in one (5%). Thus, FDG-PET provided correct N-staging in 47%, under-staging in 37%, and overstaging in 16%. CT staging was correct in 42%, underestimated in 53%, and overestimated in 5%. The maximum area of metastatic foci was 15.8 ±21.3 mm2 (mean ± SD) in false-negative nodes and 75.0±56.3 mm2 in true-positive nodes ( P Conclusion: Diagnostic accuracy of FDG-PET (47%) was low and similar to that of CT (42%). The possibility of false-negative as well as false-positive findings should be recognized in interpreting PET images. Micrometastasis appeared to be the greatest cause of false-negative findings.

Bronchogenic cysts occur most frequently in the middle mediastinum; almost all the remainder is present in the lungs. In this report, we describe 2 cases of bronchogenic cysts, which arose from the parietal and visceral pleura. Pathologically, each cyst showed an attachment with a small stalk to the parietal or visceral pleura. We suggest that bronchogenic cyst should be included in the differential diagnosis of cystic lesions in the pleural cavity.

A case of acute necrotizing pancreatitis due to Mycoplasma pneumoniae infection was treated in an 8-year-old girl. She experienced acute pancreatitis during treatment for M. pneumoniae. Contrast-enhanced computed tomographic scan revealed necrotizing pancreatitis. The computed tomographic severity index was 8 points (grade E). A protease inhibitor, ulinastatin, was provided via intravenous infusion but was ineffective. Continuous regional arterial infusion therapy was provided with gabexate mesilate (FOY-007, a protease inhibitor) and meropenem trihydrate, and the pancreatitis improved. This case suggests that infusion therapy is safe and useful in treating necrotizing pancreatitis in children.

We evaluated the ability of dual source CT (DSCT) with ECG-triggered high-pitch spiral acquisition (Flash Spiral Cardio mode) to depict the morphological features of ventricles in pediatric patients with congenital heart defects (CHD). Between July 2013 and April 2015, 78 pediatric patients with CHD (median age 4 months) were examined using DSCT with the Flash Spiral Cardio mode. The types of ventricular abnormalities were ventricular septal defect (VSD) in 42 (the malaligned type in 11, perimembranous type in 23, supracristal type in 2, atrioventricular type in 2, and muscular type in 4), single ventricle (SV) in 11, and congenital corrected transposition of the great arteries (ccTGA) in 4. We evaluated the accuracy of the diagnosis of the VSD type. In cases of SV and ccTGA, we assessed the detectability of the anatomical features of both ventricles for a diagnosis of ventricular situs. DSCT confirmed the diagnoses for all VSDs. The type of defect was precisely diagnosed for all patients. The anatomical features of both ventricles were also depicted and ventricular situs of SV and ccTGA was correctly diagnosed. The results suggest that DSCT has the ability to clearly depict the configuration of ventricles.

OBJECTIVE: The aim of the present study was to assess the technical feasibility and safety of the unilateral pulmonary artery occlusion (UPAO) test in pre-operative evaluation of pneumonectomy or pleuropneumonectomy for lung or pleural tumours. METHODS: The UPAO test was performed on 91 patients who were scheduled to undergo or were being considered for pneumonectomy or pleuropneumonectomy between June 2003 and July 2016. There were 74 males and 17 females, with a median age of 65 years (range, 23–80). The technical success rate, procedure time and complication rate were evaluated. Technical success was defined as completion of the UPAO test. RESULTS: The diagnoses of the 91 patients were as follows: lung cancer in 63, malignant pleural mesothelioma in 21, thymoma in 5, lung metastasis in 1 and lung carcinoid in 1. The UPAO test was performed successfully on 88 out of 91 patients (technical success rate: 97%). The median procedure time was 57 min (range, 34–120). Cardiac arrest due to migration of the balloon catheter to the pulmonary trunk occurred in 1 patient (complication rate: 1.1%). CONCLUSION: The UPAO test in pre-operative evaluation of pneumonectomy or pleuropneumonectomy for lung or pleural tumours appears to be technically feasible. However, it needs to be performed with care in order to avoid severe complications. ADVANCES IN KNOWLEDGE: The UPAO test can be safely performed and is helpful in evaluating patients for pneumonectomy or pleuropneumonectomy.

Purpose To assess reperfusion rates after coil embolization for pulmonary arteriovenous malformations (PAVMs) using time-resolved magnetic resonance (MR) angiography or pulmonary angiography. Materials and Methods Patients with PAVMs who underwent embolization and met the following inclusion criteria were included: ( a ) embolization was performed using bare or fibered platinum microcoils or both, ( b ) the complete cessation of flow was confirmed by digital subtraction angiography, and ( c ) follow-up examinations were conducted with time-resolved MR angiography or pulmonary angiography. Coil embolization was performed in 16 patients with 24 untreated or reperfused PAVMs. Sac embolization was performed for 12 untreated PAVMs. Feeding artery embolization was performed as primary embolization in each of the 12 reperfused PAVMs. Five PAVMs were treated 2 to 4 times because of reperfusion. The study included 32 coil embolizations. Follow-up images were reviewed, and reperfusion rates were assessed. The relationships between reperfusion and the location of PAVM, size of PAVM (feeding artery and venous sac), coils (number and total length), timing of embolization (primary or repeat embolization), and types of coils used (with or without fibered coils) were examined. Results Reperfusion rates at 3, 6, 12, and 24 months were 8%, 27%, 36%, and 49%, respectively, for the 12 untreated PAVMs (primary embolization) and 50%, 50%, 92%, and 100%, respectively, for the 12 reperfused PAVMs (repeat embolization) ( P = .0062). No significant differences were observed in the other parameters measured. Conclusions When evaluated with time-resolved MR angiography or pulmonary angiography, reperfusion rates after coil embolization for PAVM were considerably high, particularly with repeat embolization.

Although a correct diagnosis is important for appropriate management, accurately differentiating between multiple system atrophy with predominant parkinsonism (MSA-P) and Parkinson’s disease (PD) is often difficult because of similarities in the early-stage symptoms. The aim of this study was to evaluate the diagnostic value of cerebral perfusion single photon emission computed tomography (SPECT) and voxel-based analysis for diagnosing MSA-P patients. Thirty-eight subjects (9 with early-stage MSA-P, 11 with PD, and 18 controls) were included in this study. Z-scores suggestive of hypoperfusion were calculated between patients and controls using statistical parametric mapping (SPM) 8 and easy Z-score imaging system (eZIS) programs. A voxel-based stereotactic extraction estimation (vbSEE) program was performed to determine the target volumes of interest (VOIs) in the putamen, pons, and cerebellum, and quantify Z-scores as “extent” (the rate of voxels with a Z-score >2.0 in these VOIs) and “severity” (average Z-scores in these VOIs). These parameters were used as the determinant in receiver operating characteristic (ROC) analyses. The extent and severity of the cerebellar VOIs were higher in MSA-P patients than in PD patients. In ROC analyses, the extent and severity of the cerebellar VOI exhibited the highest areas under the curves of 0.86 and 0.84, and accuracies of 90 and 90 %, respectively. The diagnostic value of significant cerebellar hypoperfusion was the highest for differentiating MSA-P from PD. This voxel-based analysis of cerebral perfusion SPECT using the SPM8, eZIS, and vbSEE programs is useful for clinically diagnosing MSA-P.

Background Lower tube voltage has advantages for CT angiography, such as improved contrast Objective To evaluate the image quality of low-voltage (70 kV) CT for congenital heart disease and the ability of sinogram-affirmed iterative reconstruction to improve image quality. Materials and methods Forty-six children with congenital heart disease (median age: 109 days) were examined using dual-source CT. Scans were performed at 80 kV and 70 kV in 21 and 25 children, respectively. A nonionic iodinated contrast medium (300 mg I/ml) was used for the 80-kV protocol. The contrast medium was diluted to 75% (225 mgI/mL) with saline for the 70-kV protocol. Image noise was measured in the two protocols for each group by extracting the standard deviations of a region of interest placed on the descending aorta. We then determined whether sinogram-affirmed iterative reconstruction reduced the image noise at 70 kV. Results There was more noise at 70 kV than at 80 kV (29 ± 12 vs 20 ± 4.8; P

Laparoscopic transverse colectomy is challenging owing to technical difficulties in identifying an adequate dissection plane, ligating and dissecting lymph nodes around the middle colic vessels. One of the reasons for the technical difficulties is the complex relationship between the middle colic vein (MCV) and its tributary. So, defining the venous anatomy around the MCV before laparoscopic surgery seems important to avoid massive bleeding. The purpose of this study was to evaluate the depiction rate and variation of the MCV and its tributaries on three-dimensional CT angiography (3DCTA).This study included 331 patients (203 males and 128 females) scheduled for laparoscopic surgery between June 2010 and April 2012. Most of the patients had gastric or colorectal cancer. Patients who needed emergency surgeries for obstruction or perforation were excluded. 3DCTA with an i.v. contrast medium was performed immediately following the administration of effervescent granules or room air insufflation. We assessed variations of the MCV tributaries using transaxial, multiplanar reconstructed images and volume-rendering images.The MCV could be identified in all patients. The MCVs drained into the superior mesenteric vein in 62.5% of patients, gastrocolic trunk of Henle in 29.3% of patients, inferior mesenteric vein in 4.8% of patients, splenic vein in 2.7% of patients and jejunal vein in 0.6% of patients.3DCTA is useful in evaluating the anatomic variants of the MCV in pre-operative planning for laparoscopic surgery.Use of 3DCTA for the recognition of the anatomic complexity around the MCV and its tributary plays an important role in pre-operative planning for optimal patient outcome.

Aim To investigate the clinical and radiological features of meningitis with subarachnoid diffusion-weighted imaging (DWI) hyperintensity. Materials and methods The clinical features, laboratory data, and radiological findings, including the number and distribution of subarachnoid DWI hyperintense lesions and other radiological abnormalities, of 18 patients seen at five institutions were evaluated. Results The patients consisted of eight males and 10 females, whose ages ranged from 4 months to 82 years (median 65 years). Causative organisms were bacteria in 15 patients, including Haemophilus influenzae, Streptococcus pneumoniae, Streptococcus agalactiae, Staphylococcus aureus, Klebsiella pneumoniae, and Listeria monocytogenes. The remaining three were fungal meningitis caused by Cryptococcus neoformans. Subarachnoid DWI hyperintense lesions were multiple in 16 of the 18 cases (89%) and predominantly distributed around the frontal lobe in 16 of the 18 cases (89%). In addition to subarachnoid abnormality, subdural empyema, cerebral infarction, and intraventricular empyema were found in 50, 39, and 39%, respectively. Compared with paediatric patients, adult patients with bacterial meningitis tended to have poor prognoses (7/10 versus 1/5; p = 0.1). Conclusion Both bacterial and fungal meningitis could cause subarachnoid hyperintensity on DWI, predominantly around the frontal lobe. This finding is often associated with poor prognosis in adult bacterial meningitis.

Improved time resolution using dual-source computed tomography (DSCT) enabled adaptation of electrocardiography (ECG)-gated cardiac CT for children with a high heart rate. In this study, we evaluated the ability of ECG-gated DSCT (ECG-DSCT) to depict the morphological ventricular features in patients with congenital heart disease (CHD).Between August 2006 and March 2010, a total of 66 patients with CHD (aged 1 day to 9 years, median 11 months) were analyzed using ECG-DSCT. The type of anomaly was ventricular septal defect (VSD) in 32 (malaligned type in 20, perimembranous type in 7, supracristal type in 3, muscular type in 2), single ventricle (SV) in 11, and corrected transposition of the great arteries (cTGA) in 3. All patients underwent ECG-DSCT and ultrasonography (US). We evaluated the accuracy of diagnosing the type of VSD. For the cases with SV and cTGA, we evaluated the ability to depict anatomical ventricular features.In all 32 cases of VSD, DSCT could confirm the VSD defects, and the findings were identical to those obtained by US. Anatomical configurations of the SV and cTGA were correctly diagnosed, similar to that on US.Our study suggests that ECG-DSCT can clearly depict the configuration of ventricles.

The optimal conditions for abdominal contrast-enhanced (CE) CT, especially with respect to depiction of the hepatic veins (HVs), have not been well studied in small children. We compared the depiction of the HVs in small children using scan delay times of 50 s and 60 s and a power injector. The degree of contrast enhancement of the HVs according to body weight was also evaluated. A total of 50 CT studies in 31 children ages 2 days to 3 years 4 months (median 12 months) with a body weight less than 15 kg were prospectively evaluated. Nonionic contrast medium (300 mgI/ml) at a dose of 2 ml/kg and an injection rate calculated as (body weight in kilograms × 0.1) ml/s was injected through a 24-gauge intravenous catheter. Scan delay time was randomly chosen at 50 s or 60 s (25 times each). Subjective assessment of HV depiction was performed and the difference in CT number between the HV and hepatic parenchyma (HV−HP value) was calculated. In all cases, subjective assessment of HV depiction was good and the HV−HP value was greater than 20 HU. The mean±SD HV−HP value was 47.7±13.2 HU. There were no differences in the mean HV−HP values between scan delay times of 50 s and 60 s (P=0.58). For small children, this protocol for pediatric abdominal CECT resulted in good depiction of the HVs with no difference between scan delay times of 50 s and 60 s.

Solitary pulmonary papillomas are rare benign tumors in adults. Glandular papilloma is the rarest subtype among them. In this report, we describe a case of glandular papilloma that showed unique computed tomography features. It was a round nodule containing air spaces encapsulated with a smooth and thin wall, which suggested its endobronchial origin and a secondary change owing to air trapping.

Purpose To characterize the imaging features of thoracic hemangioma, including findings on computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) using 18F-fluoro-2-deoxy-D-glucose (FDG). Methods Six patients with thoracic wall hemangioma and 2 patients with mediastinal hemangioma were included in this study. Preoperative evaluation was performed using CT (n=7), MRI (n=8), and FDG-PET (n=2). Five cases were pathologically confirmed by surgery and the remaining 3 cases were diagnosed clinically. Results On CT, characteristic finding of phleboliths were depicted in 5 of 7 cases (71%). Fat component was demonstrated in 3 of 7 cases with CT (3/7-43%) and 5 of 8 cases with MRI (5/8-63%). On MRI, characteristic finding of high intensity on T2-weighted images was demonstrated in all 8 cases and the high signal intensity was emphasized in all 4 cases on fat-suppression T2-weighted images. Both of two PET scans showed mildly elevated accumulation of FDG. Conclusions Phleboliths, fat component, and high intensity on T2-weighted and fat-suppression T2-weighted image were thought to be characteristic findings reflecting the histologic findings. It might be useful to recognize these findings for differentiating hemangiomas from other soft tissue tumors, particularly malignant neoplasms.

The pulmonary artery (PA) is involved in most congenital heart diseases; and in these patients it is necessary to evaluate precisely the PA configuration and development. The accuracy of 16 multidetector row computed tomography (16-MDCT) in evaluating the central PA was evaluated. 16-MDCT and angiocardiography (ACG) were performed in 26 patients with various congenital heart diseases aged 7 days to 9 years (median 1.2 years). We reconstructed coronal oblique images along the long axis of the right and left PAs and measured the PA diameter and Nakata’s PA index, which were compared with those obtained by ACG. Correlations between PA diameters [R 2 = 0.80, standard error of the estimate (SEE) = 1.3, n = 52] and PA indices (R 2 = 0.81, SEE = 42, n = 26) obtained from coronal oblique images and ACG were excellent. Bland-Altman plots showed a mean ± SD difference of −0.3 ± 1.3 mm for the PA diameter and ±15.1 ± 41.5 for the PA index. 16-MDCT might be useful for evaluating the central PA in patients with congenital heart disease.

In this report, we describe a case of thymic lymphoid follicular hyperplasia that was incidentally found as a small thymic nodule in the health screening program including a low-dose chest CT. The CT and MRI findings of the nodule were similar to those of thymoma, and it was difficult to differentiate the lesion from thymoma.

The application of bronchial artery embolization (BAE) using N-butyl-2-cyanoacrylate (NBCA) for haemoptysis was recently reported to be useful. A triple co-axial (triaxial) system consisting of a 4-Fr catheter, 2.7-Fr microcatheter and 1.9-Fr no-taper microcatheter has been developed. The aim of the present study was to evaluate the usefulness of the triaxial system in BAE using NBCA.12 patients with haemoptysis, 8 males and 4 females with a median age of 64 years (range, 49-88 years), underwent BAE between August 2012 and October 2014. Medical records and images were reviewed, and the technical success rate, clinical success rate, haemoptysis-free rate and complications were evaluated. Technical success was defined as the complete cessation of the target artery as confirmed by digital subtraction angiography, whereas clinical success was defined as the cessation of haemoptysis within 24 h of BAE. Recurrent haemoptysis was defined as a total of30 ml of bleeding per day.The target artery was embolized successfully in all patients, and the technical success rate was 100% (12/12). The cessation of haemoptysis was achieved in 11 out of 12 patients within 24 h, and thus, the clinical success rate was 92% (11/12). The 6-, 12- and 24-month haemoptysis-free rates were 89%, 89% and 76%, respectively. No patients exhibited any signs of complications such as spinal ischaemia.BAE using the triaxial system and NBCA appears to be a useful and safe procedure for haemoptysis.The triaxial system contributes to safe and effective BAE using NBCA.