Vasoactive intestinal peptide increases apoptosis of hepatocellular carcinoma by inhibiting the cAMP/Bcl-xL pathway.

Vasoactive intestinal peptide (VIP) is a modulator of inflammatory responses. VIP receptors are expressed in several tumor types, such as colorectal carcinoma. The study described herein was conducted to confirm the presence of VIP and its receptors (VPAC1 and VPAC2) in surgically resected hepatocellular carcinoma (HCC) tissues and in the HCC cell line Huh7. The mechanism responsible for apoptosis of HCC cells was then examined because VIP treatment (10-10  M) significantly suppressed proliferation of Huh7 cells. In examining apoptosis-related proteins, we found caspase-3 to be significantly increased and Bcl-xL and cyclic AMP (cAMP) response element-binding protein (CREB) to be significantly decreased in Huh7 cells cultured with VIP. Furthermore, the CREB level and phosphorylation were reduced. These effects were reversed by the addition of VIP receptor antagonist or cAMP antagonist Rp-cAMPS. Pretreatment with cAMP analogue blocked the increased apoptosis, suggesting that VIP induces apoptosis via a PKA-independent signaling mechanism. Our data indicate that VIP prevents the progression of HCC by apoptosis through the cAMP/Bcl-xL pathway.

Hepcidin-25/erythroferrone ratio predicts improvement of anaemia in haemodialysis patients treated with ferric citrate hydrate.

BACKGROUND/AIMS: Hepcidin-25 (HEP-25) and erythroferrone (ERFE) are key regulators of iron homeostasis. Correlations among serum ferritin, ERFE and HEP-25 levels and improvements in anaemia have not been evaluated after administration of ferric citrate hydrate (FCH). METHODS: This retrospective observational study investigated 24 patients on haemodialysis with both anaemia (haemoglobin (Hb) < 12 g/dL) and hyperphosphatemia (inorganic phosphorus ≥6 mg/dL). The patients who were administered FCH (1500 mg/day) for 12 consecutive weeks and 12 control patients who were administered a phosphate binder other than FCH were included. Correlations among Hb, HEP-25 and ERFE levels were studied. We then stratified the FCH group into two subgroups using the median baseline values of ferritin, HEP-25, ERFE and HEP-25/ERFE ratio to predict whether these markers could serve as prognostic indicators in the treatment of anaemia. RESULTS: In the FCH group, Hb, transferrin saturation, ferritin, HEP-25 and ERFE levels were all significantly increased, while inorganic phosphorus levels, dosage of erythropoietin-stimulating agent, and erythropoietin resistance index were all significantly decreased after drug administration. A significant inverse correlation was apparent between Hb and HEP-25 levels, and a significant positive correlation was seen between Hb and ERFE levels. A significant inverse correlation was found between HEP-25 and serum ERFE levels. Compared with the high HEP-25/ERFE ratio group, only the low HEP-25/ERFE ratio group exhibited significantly increased Hb levels at 12 weeks. CONCLUSION: HEP-25/ERFE ratio could be a novel prognostic marker for increases in Hb levels following FCH administration.

The renal pathological findings in Japanese HIV-infected individuals with CKD: a clinical case series from a single center.

BACKGROUND: Chronic kidney diseases (CKD) have emerged as a significant cause of morbidity and mortality in patients infected with human immunodeficiency virus (HIV). However, the detailed study of renal pathological findings currently remains unclear in these Japanese patients. METHODS: A retrospective cohort study was undertaken to investigate renal pathological findings between January 1996 and July 2016. Our study included 20 Japanese HIV-infected patients with CKD; 10 cases had undergone renal biopsies, and 10 cases had undergone autopsies, respectively. Moreover, in the 10 biopsied patients, their clinical courses as well as renal outcomes after renal biopsy were also reviewed. RESULTS: All of the patients had received combination antiretroviral therapy (cART). The 10 biopsy cases (mean age, 54 ± 14 years and duration of cART, 8 ± 5 years) included three cases of diabetic nephropathy (DMN), two of IgA nephropathy, two of cART-induced tubulointerstitial nephritis (TIN), one of minimal change disease, one case of only finding intrarenal arterioles, and one case without abnormal findings. Among those patients, their clinical courses were preferable except for in the DMN cases. In the autopsy cases (mean age, 52 ± 10 years and duration of cART, 5 ± 5 years), no distinct mesangial or membranous abnormalities were detected. Mild to moderate tubulointerstitial atrophies were observed in six cases. Intrarenal arteriosclerosis was identified in nine cases, and the proportion of global glomerulosclerosis seen was 8.4 ± 12.5%/100 glomeruli. CONCLUSION: DMN and cART-induced TIN was noted in the biopsy cases. In the autopsy cases, renal arteriosclerosis, global glomerulosclerosis, and tubulointerstitial atrophy were remarkable. Early diagnosis of kidney diseases should be crucial to introduce optimal management, including controlling rigorous comorbidities and appropriate use of cART, to prevent further progression of CKD.

JLCS medical practice guidelines for thymic tumors: summary of recommendations.

The Guideline Committee of the Japan Lung Cancer Society (JLCS) for Thymic Tumors published the Medical Practice Guideline for Thymic Tumors in Japanese as Chapter 3 of the Medical Practice Guidelines for Lung Cancers according to evidence-based medicine in December 2016. This medical practice guideline is the first for thymic epithelial tumors in Japan, and comprises a set of recommendations covering clinical diagnosis, treatment and pathological diagnosis. Thymic epithelial tumors include thymoma, thymic carcinoma and thymic neuroendocrine tumor. The recommendations for clinical diagnosis concern detection of the symptoms, blood and serum tests according to clinical presentation, essential imaging for differential diagnosis and staging, and the necessity and methods of definitive diagnosis. The recommendations for treatment are dependent on tumor stage and recurrence status, and the treatment modalities included surgery, radiation therapy, chemotherapy and multimodality therapy. Those for pathological diagnosis deal with the handing methods of resected specimen and essential reporting contents for pathological diagnosis. Since data from large-scale analyses or clinical studies of thymic epithelial tumor are limited due to its low prevalence, the relevant recommendations and grading were based on available reported evidence and expert opinions as well as diagnostic methods and treatments commonly used in Japan. This report summarizes the recommendations concerning each topic addressed by this JLCS guideline for thymic tumors.

Increased non-HDL-C level linked with a rapid rate of renal function decline in HIV-infected patients.

BACKGROUND: The risk of developing CKD is increased in HIV-infected patients; however, the relationship between renal function decline and lipid abnormalities currently remains unclear in these patients. METHODS: A retrospective cohort study was conducted on 661 HIV-infected patients, whose estimated glomerular filtration rates (eGFRs) were consecutively measured over 6 years. The rate of declines in eGFR per year was calculated, with decreases being evaluated using a linear mixed effect model. The distribution of decreases in eGFR ≥ 30 % from baseline during the follow-up period was compared across quartiles of non-high-density lipoprotein cholesterol (HDL-C) levels using the Cochran-Armitage test. A multivariate logistic regression model was built to examine the relationship between dyslipidemia and decreases in eGFR. RESULTS: The prevalence of CKD increased from 8.5 to 21.2 % during the follow-up. The average of 6 annual eGFR decline rates was 2.01 ± 0.09 ml/min/1.73 m2/year, which was more than 6-fold higher than that of age-matched controls. The distribution of decreases in eGFR significantly increased across the quartiles of non-HDL-C (p value for trend = 0.0359). Non-HDL-C levels greater than the median value of the cohort were identified as a significant risk factor for decreased eGFR [odds ratio (95 % confidence interval), 1.77 (1.07-3.00)]. CONCLUSION: Increased non-HDL-C levels are a risk factor for renal function decline in HIV-infected patients.

Associations between computed tomography features of thymomas and their pathological classification.

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.

Utility of Electrocardiography (ECG)-Gated Computed Tomography (CT) for Preoperative Evaluations of Thymic Epithelial Tumors.

BACKGROUND: Preoperative evaluation of invasion to the adjacent organs is important for the thymic epithelial tumors on CT. The purpose of our study was to evaluate the utility of electrocardiography (ECG)-gated CT for assessing thymic epithelial tumors with regard to the motion artifacts produced and the preoperative diagnostic accuracy of the technique. MATERIAL/METHODS: Forty thymic epithelial tumors (36 thymomas and 4 thymic carcinomas) were examined with ECG-gated contrast-enhanced CT using a dual source scanner. The scan delay after the contrast media injection was 30 s for the non-ECG-gated CT and 100 s for the ECG-gated CT. Two radiologists blindly evaluated both the non-ECG-gated and ECG-gated CT images for motion artifacts and determined whether the tumors had invaded adjacent structures (mediastinal fat, superior vena cava, brachiocephalic veins, aorta, pulmonary artery, pericardium, or lungs) on each image. Motion artifacts were evaluated using a 3-grade scale. Surgical and pathological findings were used as a reference standard for tumor invasion. RESULTS: Motion artifacts were significantly reduced for all structures by ECG gating (p=0.0089 for the lungs and p<0.0001 for the other structures). Non-ECG-gated CT and ECG-gated CT demonstrated 79% and 95% accuracy, respectively, during assessments of pericardial invasion (p=0.03). CONCLUSIONS: ECG-gated CT reduced the severity of motion artifacts and might be useful for preoperative assessment whether thymic epithelial tumors have invaded adjacent structures.

Serum hepcidin-25 level linked with high mortality in patients with non-Hodgkin lymphoma.

Hepatic hepcidin-25 production is stimulated by systemic inflammation, and it interferes with the body's utilization of iron, leading to anemia. A 1-year prospective study was conducted to elucidate an association of serum hepcidin-25 concentration with mortality in anemic patients with non-Hodgkin lymphoma (NHL). Serum hepcidin-25 levels were measured in 50 NHL patients using liquid chromatography-tandem mass spectrometry. The patients were stratified into a high- and a low-hepcidin-25 group according to the median of serum hepcidin-25 concentrations. Factors associated with hemoglobin (Hb) were determined by multivariate regression analysis, incorporating serum hepcidin-25 and inflammatory markers including ferritin and interleukin-6 (IL-6) as covariates. The association between serum hepcidin-25 and mortality was analyzed using both the Kaplan-Meier method and a multivariate proportional hazards regression model. The median of serum hepcidin-25 concentrations was 49.8 (0.6-269) ng/mL, a level approximately nine times greater than the reference value for healthy individuals. Hb level was significantly lower in the high than in the low-hepcidin-25 group. Serum hepcidin-25 was extracted as the significant factor associated with Hb, but neither ferritin nor IL-6 was. The cumulative mortality was significantly greater in the high than in the low-hepcidin-25 group (56.0 vs. 24.0 %; P = 0.0222). The mortality risk for the presence of high hepcidin-25 was four times greater (hazard ratio [95 % confidence interval]: 3.66 [1.12-16.4]). In conclusion, serum hepcidin-25 levels are elevated in anemic NHL patients, and in this study, the group with higher hepcidin-25 levels manifested advanced anemia and poor survival.

MRI for differentiation of renal cell carcinoma with sarcomatoid component from other renal tumor types.

PURPOSE: To investigate the usefulness of MRI for detection of sarcomatoid renal cell carcinoma (SRCC) components within RCC and differentiation from other renal tumors. METHODS: Two observers independently interpreted T2-weighted images of 10 patients with pathologically confirmed RCCs with SRCC and 131 with non-SRCC renal tumors, with special reference to conspicuously low signal intensity (SI) areas (T2LIA) compared to the renal cortex. SRCC probability was classified as (1) definitely non-SRCC, no T2LIA; (2) probably non-SRCC, <1 cm T2LIA; (3) low probability of SRCC, homogeneous tumor with 1-3 cm T2LIA; (4) probably SRCC, heterogeneous tumor with 1-3 cm T2LIA; and (5) definitely SRCC, >3 cm T2LIA, multiple >1 cm T2LIAs, or showing disruption of the pseudocapsule. The observers used chemical shift imaging to exclude the area representing hemorrhage or hemosiderin deposition from T2LIA. Scores of 4/5 were regarded as positive for evaluating the accuracy and area under the receiver operating characteristic curve. The SI ratio of the lowest SI in the tumor to that of the renal cortex in the 1 and ≥2 score groups was compared using Mann-Whitney's U test. RESULTS: Sensitivity, specificity, accuracy, and positive and negative predictive values were 90%, 95%, 94%, 56%, and 99%, respectively, and area under the receiver operating characteristic curve was 0.93. The mean SI ratio of the lowest SI in the tumor to that of the renal cortex was significantly lower in the ≥2 score group (0.58) than in the 1 score group (1.36). CONCLUSIONS: MRI predicted RCC with SRCC with a moderate positive predictive value and a high negative predictive value.

Measurements of procalcitonin facilitate targeting of endotoxin adsorption treatment in febrile neutropenic patients suffering from shock.

Immediate initiation of hemoperfusion treatment with polymixin B immobilized fiber (PMX-DHP) is a potent strategy to improve hemodynamics in septic patients with critical circulatory failure. However, it is often difficult to accurately and rapidly differentiate between bacterial infections and non-infectious causes of shock in acutely critically-ill patients. Procalcitonin (PCT) measurements may assist in the early identification of bacterial infection/sepsis and determination of severity in such patients. We present two febrile neutropenic (FN) patients who developed severe shock after chemotherapy for hematological malignancies. PCT levels were markedly elevated in both patients (≥ 10 ng/ml), suggesting a high likelihood of bacterial infectious etiology as the cause of their shock, and thus they were promptly treated with PMX-DHP. Measurements of PCT may facilitate targeting of PMX-DHP treatment among FN patients suffering from shock, which may lead to better prognosis.

Proteinuria is a simple sign of systemic inflammation that leads to a poor prognosis in individuals affected with non-Hodgkin lymphoma.

BACKGROUND: The clinical significance of proteinuria has not been fully understood among patients who are affected with non-Hodgkin lymphoma (NHL). METHODS: A 1-year prospective cohort study was conducted to ascertain the association between proteinuria and mortality in 46 hospitalized NHL patients. Proteinuria was defined as persistent dipstick test >= 1+, and the urinary protein creatinine ratio (UPCR),as a quantitative index of protein excretion, was measured simultaneously. A multivariable linear regression model was constructed to determine factors associated with UPCR. Statistical associations between proteinuria and time to mortality were analyzed using the Kaplan-Meier method and multivariable proportional hazards regression analysis, adjusted for covariates including disease severity, renal function, and serum interleukin-6(IL-6) concentration. RESULTS: The prevalence of proteinuria was 15.2% in the NHL patients. UPCR was significantly associated with the serum IL-6 level (standardized beta = 0.360, p = 0.0440). The cumulative mortality was significantly higher in proteinuric patients than in non-proteinuric patients, with a graded relationship between the severity of UPCR and mortality. The mortality risk increased with increasing UPCR grade: the hazard ratio (95% confidence interval) was 4.90 (1.29 - 32.3) for UPCR 30 - 300 mg/gand 17.8 (2.84 - 150) for UPCR > 300 mg/g, respectively, when UPCR < 30 mg/g was set as the reference. CONCLUSIONS: Proteinuria is a simple sign of coexisting systemic inflammation due to NHL and a harbinger of a poor prognosis.

Computed tomography radiomic feature analysis of thymic epithelial tumors: Differentiation of thymic epithelial tumors from thymic cysts and prediction of histological subtypes.

PURPOSE: To investigate the value of computed tomography (CT) radiomic feature analysis for the differential diagnosis between thymic epithelial tumors (TETs) and thymic cysts, and prediction of histological subtypes of TETs. MATERIALS AND METHODS: Twenty-four patients with TETs (13 low-risk and 9 high-risk thymomas, and 2 thymic carcinomas) and 12 with thymic cysts were included in this study. For each lesion, the radiomic features of a volume of interest covering the lesion were extracted from non-contrast enhanced CT images. The Least Absolute Shrinkage and Selection Operator (Lasso) method was used for the feature selection. Predictive models for differentiating TETs from thymic cysts (model A), and high risk thymomas + thymic carcinomas from low risk thymomas (model B) were created from the selected features. The receiver operating characteristic curve was used to evaluate the effectiveness of radiomic feature analysis for differentiating among these tumors. RESULTS: In model A, the selected 5 radiomic features for the model A were NGLDM_Contrast, GLCM_Correlation, GLZLM_SZLGE, DISCRETIZED_HISTO_Entropy_log2, and DISCRETIZED_HUmin. In model B, sphericity was the only selected feature. The area under the curve, sensitivity, and specificity of radiomic feature analysis were 1 (95% confidence interval [CI]: 1-1), 100%, and 100%, respectively, for differentiating TETs from thymic cysts (model A), and 0.76 (95%CI: 0.53-0.99), 64%, and 100% respectively, for differentiating high-risk thymomas + thymic carcinomas from low-risk thymomas (model B). CONCLUSION: CT radiomic analysis could be utilized as a non-invasive imaging technique for differentiating TETs from thymic cysts, and high-risk thymomas + thymic carcinomas from low-risk thymomas.

MR imaging of urinary bladder cancer for T-staging: a review and a pictorial essay of diffusion-weighted imaging.

Treatment decisions for bladder cancer patients are mainly based on the depth of bladder wall invasion by the tumor. In this article, we review the conventional MRI and exhibit a recently emerged diffusion-weighted imaging (DWI) of urinary bladder cancer for T-staging. We discuss limitations of conventional MRI, scanning protocols of DWI, normal pelvic findings on DWI, determination of T-stage using DWI, and pitfalls of DWI. DWI provides high contrast between bladder cancer and background tissue because the cancer shows markedly high SI. DWI has high sensitivity for detecting the stalk seen in stage Ta or T1. An inflammatory change or fibrosis surrounding the tumor mimics the invasion of bladder cancer on T2-weighted imaging or enhanced MRI and could lead to over-staging, but DWI could differentiate them clearly because these benign changes do not show high SI on DWI. DWI is also useful for detecting ureteral, urethral, and prostatic extension by means of the urethra. DWI provides more accurate information on the extent of bladder cancer and contributes to determination of the treatment strategy.

S100A12 gene expression is increased in peripheral leukocytes in chronic kidney disease stage 4-5 patients with cardiovascular disease.

BACKGROUND/AIMS: S100A12 induces vascular inflammation contributing to the development of atherosclerosis. Serum S100A12 concentration is shown to be elevated in patients with chronic kidney disease (CKD), however the reason remains unclear. METHODS: Transcriptional levels of S100A12 and RAGE (receptor for advanced glycation end products) were measured in peripheral leukocytes by quantitative real-time RT-PCR. Subjects were 40 patients with CKD stage 4-5, 20 of whom were affected with cardiovascular disease (CVD), and 20 healthy subjects. Serum concentrations of S100A12 and soluble RAGE were measured using enzyme-linked immunosorbent assay. RESULTS: The serum concentration of S100A12 was significantly higher in CKD patients than in healthy subjects (78.5 ± 70.5 vs. 23.7 ± 19.2 ng/ml, p = 0.0035), but that of soluble RAGE was not. The relative quantity of S100A12 mRNA was significantly greater in leukocytes from CKD patients than in those from healthy subjects [mean (95% confidence interval of the mean): 3.1 (2.2-3.9) vs. 1.2 (0.8-1.7), p = 0.0001], however that of RAGE mRNA was not. The serum concentration of S100A12 was significantly correlated with the relative quantity of S100A12 mRNA among uremic CKD patients (r(2) = 0.656, p < 0.0001). Both the serum concentration and gene expression of S100A12 were significantly higher in patients who had CVD than in those who did not. CONCLUSION: Excessive expression of the S100A12 gene in uremic leukocytes is relevant to its increased serum concentration, particularly in those affected with CVD.

A case of IgA nephropathy associated with mycosis fungoides that developed into rapidly progressive glomerulonephritis.

A 53-year-old Japanese male was diagnosed with atopic dermatitis and initiated treatment with a local dermatologist in February 2001. A routine medical check-up revealed proteinuria, microscopic hematuria and slight elevation of serum creatinine level in spring 2006. He was referred to our hospital for nephrology consultation and followup.In December 2009, he developed a sudden high fever of greater than 39 °C with sore throat. In addition, his serum creatinine level greatly increased to 4.6 mg/dl. His prevalent renal illness was thought to be rapidly progressive glomerulonephritis (RPGN). Soon after admission, kidney and skin biopsies were performed. The kidney specimens showed that the glomeruli had proliferative mesangial cells strongly positive for anti-IgA antibody, 75% of which manifested fibrocellular crescentic formation surrounding the Bowman's capsules. His skin disease was pathologically proven to be mycosis fungoides(MF). It is likely that his kidney disease was exacerbated by the upper respiratory tract infection and converted to RPGN. Ash is kidney function rapidly declined, hemodialysis therapy was initiated and he remains on chronic dialysis therapy. This is a serious case of IgA nephropathy associated with MF,which developed into RPGN and subsequent end-stage renal disease.

Segmental multicystic dysplastic kidney in an adult: usefulness of enhanced CT in excretory phase.

We present an adult case of segmental multicystic dysplastic kidney (SMCDK). The patient had a 10 × 6 cm oval-shaped mass consisting of a solid and multilocular cystic component at the right upper renal sinus. The solid component showed gradual and mild enhancement on dual-phase enhanced CT. Excretory-phase CT demonstrated the excretion of contrast medium into the septa and cysts. Dilation of the upper calices and renal pelvis and atretic renal pelvis in the mass were also clearly visualized in the excretory phase. The signal intensity of the solid component was slightly lower than that of the renal parenchyma on T2-weighted images and similar to that of the medulla on diffusion-weighted images. Right nephrectomy showed a multilocular cystic component within the renal sinus and some of the cysts contained blood. The renal pelvis of the upper moiety was blind, as suggested by CT. Microscopically, there were multiple non-communicating small cysts, as shown by CT, and the wall was lined with immature tubule-like cells. In addition, immature tubule-like cells were seen in the septa. Immature mesenchymal cells were seen around the cysts. The solid component mainly consisted of fibroconnective tissue with immature tubule-like cells. The pathological diagnosis was confirmed as SMCDK. Excretion of contrast media into the septum and cystic component might be a characteristic finding of SMCDK in addition to the finding of a multilocular cystic mass in the upper moiety with urinary tract abnormality.

Utility of high-definition FDG-PET image reconstruction for lung cancer staging.

BACKGROUND: High-definition (HD) positron emission tomography (PET) image reconstruction is a new image reconstruction method based on the point spread function system, which improves the spatial resolution of the images. PURPOSE: To compare the utility of HD reconstruction of PET images for staging lung cancer with that of conventional 2D ordered subset expectation maximization + Fourier rebinning (2D) reconstruction. MATERIAL AND METHODS: Thirty-five lung cancer patients (24 men, 11 women; median age, 66 years) who underwent surgery after 18F-2-deoxy-fluoro-D-glucose (FDG)-PET-CT were studied. Their PET data were reconstructed with 2D and HD PET reconstruction algorithms. Two radiologists individually TNM staged both sets of images. They also evaluated the quality of the images and the diagnostic confidence that the images afforded them using 5-point scales. RESULTS: T, N, and M stages were correctly diagnosed on both the 2D and HD reconstructed images in 23 (66%), 25 (71%), and 30 (86%) of 35 cases, respectively. Overall TNM stage was correctly diagnosed on both types of reconstructed images in 23 cases (66%), underestimated in three (9%), and overestimated in nine (26%). No significant difference in T, N, or M stage or overall TNM stage was observed between the two reconstruction methods. However, the HD reconstructed images afforded a significantly higher level of diagnostic confidence during TNM staging than the 2D reconstructed images and were also of higher quality than the 2D reconstructed images. CONCLUSION: Although HD reconstruction of FDG-PET images did not improve the diagnostic accuracy of lung cancer staging compared with 2D reconstruction, the quality of the HD reconstructed images and the diagnostic confidence level they afforded the radiologists were higher than those of the conventional 2D reconstructed images.

Accuracy of iodine removal using dual-energy CT with or without a tin filter: an experimental phantom study.

BACKGROUND: The effects of a tin filter on virtual non-enhanced (VNE) images created by dual-energy CT have not been well evaluated. PURPOSE: To compare the accuracy of VNE images between those with and without a tin filter. MATERIAL AND METHODS: Two different types of columnar phantoms made of agarose gel were evaluated. Phantom A contained various concentrations of iodine (4.5-1590 HU at 120 kVp). Phantom B consisted of a central component (0, 10, 25, and 40 mgI/cm(3)) and a surrounding component (0, 50, 100, and 200 mgI/cm(3)) with variable iodine concentration. They were scanned by dual-source CT in conventional single-energy mode and dual-energy mode with and without a tin filter. CT values on each gel at the corresponding points were measured and the accuracy of iodine removal was evaluated. RESULTS: On VNE images, the CT number of the gel of Phantom A fell within the range between -15 and +15 HU under 626 and 881 HU at single-energy 120 kVp with and without a tin filter, respectively. With attenuation over these thresholds, iodine concentration of gels was underestimated with the tin filter but overestimated without it. For Phantom B, the mean CT numbers on VNE images in the central gel component surrounded by the gel with iodine concentrations of 0, 50, 100, and 200 mgI/cm(3) were in the range of -19-+6 HU and 21-100 HU with and without the tin filter, respectively. CONCLUSION: Both with and without a tin filter, iodine removal was accurate under a threshold of iodine concentration. Although a surrounding structure with higher attenuation decreased the accuracy, a tin filter improved the margin of error.

Changes of fractional anisotropy and apparent diffusion coefficient in patients with idiopathic normal pressure hydrocephalus.

Since ventricular dilation and periventricular abnormal intensities are commonly seen in patients with idiopathic normal pressure hydrocephalus (INPH) on magnetic resonance imaging (MRI), dysfunction of white matter may have an important role in the mechanism causing symptoms of INPH. To clarify the pathophysiology of INPH, we analyzed axonal water dynamics using diffusion tensor MRI. Thirty-six patients with possible INPH were included. Regional fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were measured in several white matter regions before and 24 h after a cerebrospinal fluid tap test (CSF-TT). The patients were divided into two groups: patients who showed significant improvements in neurological status after the CSF-TT (positive, n = ;17) and those with no neurological improvement (negative, n = 19). After CSF-TT, ADC values were significantly decreased in the frontal periventricular region and the body of the corpus callosum in the positive group (p < 0.05), whereas no significant change was shown in the negative group. FA values were significantly increased in the body of the corpus callosum in both groups after CSF-TT (p < 0.05). After CSF-TT, water molecules at the extracellular space could move to the intraventricular space, resulting in decreased ADC values. This suggests that changes of water dynamics in white matter may have a role in the mechanism causing symptoms of INPH.