LHFFNet: A hybrid feature fusion method for lane detection.

Lane line images have the essential attribute of large-scale variation and complex scene information, and the similarity between adjacent lane lines is high, which can easily cause classification errors. And remote lane lines are difficult to recognize due to visual angle changes in width. To address this issue, this paper proposes an effective lane detection framework, which is a hybrid feature fusion network that enhances multiple spatial features and distinguishes key features throughout the entire lane line segment. It enhances and fuses lane line features at multiscale to enhance the feature representation of lane line images, especially at the far end. Firstly, in order to enhance the correlation of multiscale lane features, a multi-head self attention is used to construct a multi-space attention enhancement module for feature enhancement in multispace. Secondly, a spatial separable convolutional branch is designed for the jumping layer structure connecting multiscale lane line features. While retaining feature information of different scales, important lane areas in multiscale feature information are emphasized through the allocation of spatial attention weights. Finally, considering that lane lines are elongated areas in the image, and the background information in the image is much more abundant than lane line information, the flexibility of traditional pooling operations in capturing widely existing anisotropic contexts in actual environments is limited. Therefore, before embedding feature output branches, strip pooling is introduced to refine the representation of lane line information and optimize model performance. The experimental results show that the accuracy on the TuSimple dataset reaches 96.84%, and the F1 score on the CULane dataset reaches 75.9%.

Sequential Oxidation/Cyclization of Readily Available Imine Linkages to Access Benzoxazole-Linked Covalent Organic Frameworks.

Benzoxazole-linked covalent organic frameworks (BO-COFs), despite their exceptional chemical stability, are still in their infancy. This is primarily because the current prevalent methods require the use of special ortho-hydroxyl-substituted aromatic amines as monomers. Herein, we report an innovative strategy to access BO-COFs directly from imine-linked COFs (Im-COFs) without pre-embedded OH groups, using a two-step sequential oxidation/cyclization process. The two-step process included the oxidation of Im-COFs into amide-linked COFs, followed by a copper-catalyzed oxidative cyclization. Five representative BO-COFs were synthesized with retained crystallinity and high oxidization efficiency, offering the potential to convert a significant portion of Im-COFs into BO-COFs. The structural advantages of the newly designed BO-COFs were demonstrated through their application to photocatalytic organic transformations.

Embedding Hydrogen Atom Transfer Moieties in Covalent Organic Frameworks for Efficient Photocatalytic C-H Functionalization.

Covalent organic frameworks (COFs) have emerged as efficient heterogeneous photocatalysts for a wide range of relatively simple organic reactions, whereas their application in complex organic transformations, like site-selective functionalization of unactivated C-H bonds, is underexplored, which can be mainly attributed to the lack of highly active organophotocatalytic cores. Herein through bonding oxygen atoms at the N-terminus of quinolines in nonsubstituted quinoline-linked COFs (NQ-COFs), we successfully realized the embedding of active hydrogen atom transfer (HAT) moieties into the skeleton of COFs. This novel designed COF (NQ-COFE5 -O), serving as both an excellent photosensitizer and HAT catalyst, exhibited much higher efficiency in C-H functionalization than the corresponding NQ-COFE5 . Specially, we evaluated the photocatalytic performance of NQ-COFE5 -O on ten different substrates, including quinolines, benzothiazole, and benzoxazole, all of which were transferred to desired products in moderate to high yields (up to 93 %). Furthermore, the as-synthesized NQ-COFE5 -O displayed excellent photostability and could be reused with negligible loss of activity for five catalytic cycles.

Mechanochemical Synthesis of PdO2 Nanoparticles Immobilized over Silica Gel for Catalytic Suzuki-Miyaura Cross-Coupling Reactions Leading to the C-3 Modification of 1H-Indazole with Phenylboronic Acids.

The C-3 modification of 1H-indazole has produced active pharmaceuticals for the treatment of cancer and HIV. But, so far, this transformation has seemed less available, due to the lack of efficient C-C bond formation at the less reactive C-3 position. In this work, a series of silica gel-supported PdO2 nanoparticles of 25-66 nm size were prepared by ball milling silica gel with divalent palladium precursors, and then employed as catalysts for the Suzuki-Miyaura cross-coupling of 1H-indazole derivative with phenylboronic acid. All the synthesized catalysts showed much higher cross-coupling yields than their palladium precursors, and could also be reused three times without losing high activity and selectivity in a toluene/water/ethanol mixed solvent. Although the palladium precursors showed an order of activity of PdCl2(dppf, 1,1'-bis(diphenylphosphino)ferrocene) > PdCl2(dtbpf, 1,1'-bis(di-tert-butylphosphino)ferrocene) > Pd(OAc, acetate)2, the synthesized catalysts showed an order of C1 (from Pd(OAc)2) > C3 (from PdCl2(dtbpf)) > C2 (from PdCl2(dppf)), which conformed to the orders of BET (Brunauer-Emmett-Teller) surface areas and acidities of these catalysts. Notably, the most inexpensive Pd(OAc)2 can be used as a palladium precursor for the synthesis of the best catalyst through simple ball milling. This work provides a highly active and inexpensive series of catalysts for C-3 modification of 1H-indazole, which are significant for the large-scale production of 1H-indazole-based pharmaceuticals.

Induction of antitumor immunity in mice by the combination of nanoparticle-based photothermolysis and anti-PD-1 checkpoint inhibition.

Generation of durable tumor-specific immune response without isolation and expansion of dendritic cells or T cells ex vivo remains a challenge. In this study, we investigated the impact of nanoparticle-mediated photothermolysis in combination with checkpoint inhibition on the induction of systemic antitumor immunity. Photothermolysis based on near-infrared light-absorbing copper sulfide nanoparticles and 15-ns laser pulses combined with the immune checkpoint inhibitor anti-PD-1 antibody (αPD-1) increased tumor infiltration by antigen-presenting cells and CD8-positive T lymphocytes in the B16-OVA mouse model. Moreover, combined photothermolysis, polymeric conjugate of the Toll-like receptor 9 agonist CpG, and αPD-1 significantly prolonged mouse survival after re-inoculation of tumor cells at a distant site compared to individual treatments alone in the poorly immunogenic syngeneic ID8-ip1-Luc ovarian tumor model. Thus, photothermolysis is a promising interventional technique that synergizes with Toll-like receptor 9 agonists and immune checkpoint inhibitors to enhance the abscopal effect in tumors.

Clinical application of diffusion-weighted magnetic resonance imaging in radiotherapy for nasopharyngeal carcinoma.

OBJECTIVE: To explore the clinical application of diffusion-weighted magnetic resonance imaging (DWI) in nasopharyngeal carcinoma (NPC) diagnosis, detection of lymph node metastasis, radiotherapy and prognosis. METHODS: Twenty patients with diagnosed NPC in an early stage of radiotherapy were enrolled in our department between May 2010 and May 2013. T1 and T2 weighted magnetic resonance imaging and DWI of the nasopharynx and neck were performed 1 week before radiotherapy, during radiotherapy at a dose of 60 Gy, and 1 month after radiotherapy. Pertinent measurements and related data were recorded. RESULTS: In comparison with that before radiotherapy, the ADC value of the nasopharyngeal primary lesion increased significantly during radiotherapy at a dose of 60 Gy and at 1 month after radiotherapy (F = 187.160, P = 0.000). When the dose of radiotherapy reached 60 Gy, the DWI signals from both the neck and the retropharyngeal lymph nodes were significantly lower than those before radiotherapy. CONCLUSION: DWI can be used for sensitive and accurate diagnosis of lymph node metastasis in the neck and retropharyngeal space, monitoring of the radiotherapy effect in early stages of NPC and development of new medical treatment strategies.

Short-Term Outcome of Patients with Cirrhosis and Concurrent Portal Cavernoma Presenting with Acute Variceal Bleeding.

Background and Aim: The outcome of cirrhotic patients with main portal vein occlusion and portal cavernoma after the first episode of acute variceal bleeding (AVB) is unknown. We compared short-term outcomes after AVB in cirrhotic patients with and without portal cavernoma. Methods: Between January 2009 and September 2014, 28 patients with cirrhosis and portal cavernoma presenting with the first occurrence of AVB and 56 age-, sex-, and Child-Pugh score-matched cirrhotic patients without portal cavernoma were included. The primary endpoints were 5-day treatment failure and 6-week mortality. Results: The 5-day treatment failure rate was higher in the cavernoma group than in the control group (32.1% versus 12.5%; p = 0.031). The 6-week mortality rate did not differ between the cavernoma and control group (25% versus 12.5%, p = 0.137). Multivariable Cox proportional hazard regression analyses revealed that 5-day treatment failure (HR = 1.223, 95% CI = 1.082 to 1.384; p = 0.001) independently predicted 6-week mortality. Conclusions: Cirrhotic patients with AVB and portal cavernoma have worse short-term prognosis than patients without portal cavernoma. The 5-day treatment failure was an independent risk factor for 6-week mortality in patients with cirrhosis and portal cavernoma.

MicroPET/CT Imaging of AXL Downregulation by HSP90 Inhibition in Triple-Negative Breast Cancer.

AXL receptor tyrosine kinase is overexpressed in a number of solid tumor types including triple-negative breast cancer (TNBC). AXL is considered an important regulator of epithelial-to-mesenchymal transition (EMT) and a potential therapeutic target for TNBC. In this work, we used microPET/CT with 64Cu-labeled anti-human AXL antibody (64Cu-anti-hAXL) to noninvasively interrogate the degradation of AXL in vivo in response to 17-allylamino-17-demethoxygeldanamycin (17-AAG), a potent inhibitor of HSP90. 17-AAG treatment caused significant decline in AXL expression in orthotopic TNBC MDA-MB-231 tumors, inhibited EMT, and delayed tumor growth in vivo, resulting in significant reduction in tumor uptake of 64Cu-anti-hAXL as clearly visualized by microPET/CT. Our data indicate that 64Cu-anti-hAXL can be useful for monitoring anti-AXL therapies and for assessing inhibition of HSP90 molecular chaperone using AXL as a molecular surrogate.

Role of CTGF in Sensitivity to Hyperthermia in Ovarian and Uterine Cancers.

Even though hyperthermia is a promising treatment for cancer, the relationship between specific temperatures and clinical benefits and predictors of sensitivity of cancer to hyperthermia is poorly understood. Ovarian and uterine tumors have diverse hyperthermia sensitivities. Integrative analyses of the specific gene signatures and the differences in response to hyperthermia between hyperthermia-sensitive and -resistant cancer cells identified CTGF as a key regulator of sensitivity. CTGF silencing sensitized resistant cells to hyperthermia. CTGF small interfering RNA (siRNA) treatment also sensitized resistant cancers to localized hyperthermia induced by copper sulfide nanoparticles and near-infrared laser in orthotopic ovarian cancer models. CTGF silencing aggravated energy stress induced by hyperthermia and enhanced apoptosis of hyperthermia-resistant cancers.

Does adding variceal status to the Child-Turcotte-Pugh score improve its performance in predicting mortality in cirrhosis?

The Child-Turcotte-Pugh (CTP) score is widely used worldwide to predict outcomes across a broad spectrum of liver diseases, mainly cirrhosis. Portal hypertension and variceal bleed are significant causes of morbidity and mortality in cirrhotic patients, although the variceal status is not incorporated into the classical CTP score. We sought to determine whether the inclusion of variceal status, specifically the Child-Turcotte-Pugh-Kumar (CTPK) score, would improve the utility of the classical CTP score to predict the clinical outcomes of cirrhotic patients in a single but high-volume center in China.We retrospectively analyzed the records of 253 patients from January 1, 2014 to December 31, 2014 and performed follow-up for at least 12 months. The CTPK score and the CTP score were obtained as soon as possible after the patient's admission. Telephone follow-up was performed to assess survival situations.At 3 and 12 months, the cumulative number of deaths was 9.1% (n = 23) and 13.8% (n = 35), respectively. In the multivariate Cox proportional hazards models, the CTPK score was independently associated with death within 3 and 12 months after adjusting for potential confounders. The predictive ability related to the 2 scores was evaluated by the area under the receiver operating characteristic curve (AUC-ROC) respectively. At 3 months of enrollment, the AUCs of CTPK and CTP were 0.814 and 0.838, respectively. At 12 months of enrollment, the AUCs of CTPK and CTP were 0.825 and 0.840, respectively. No significant difference between time points was observed. Both the CTPK score and the CTP score displayed prognostic value in cirrhotic patients, as the Kaplan-Meier analysis showed that the CTPK score could clearly discriminate patients in the intermediate term (P < 0.001).The CTPK score provides reliable prediction of mortality in Chinese cirrhotic patients for both short-term and medium-term prognoses, although it is not superior to the CTP score. Therefore, the CTP score remains an excellent tool for outcome prediction in patients with cirrhosis, and greater attention to variceal status may be in veins, even for patients with a history of variceal bleed or medium/large varices.

Hepatocellular Carcinoma: Intra-arterial Delivery of Doxorubicin-loaded Hollow Gold Nanospheres for Photothermal Ablation-Chemoembolization Therapy in Rats.

Purpose To determine if combretastatin A-4 phosphate disodium (CA4P) can enhance the tumor uptake of doxorubicin (Dox)-loaded, polyethylene glycol (PEG)-coated hollow gold nanospheres (HAuNS) mixed with ethiodized oil for improved photothermal ablation (PTA)-chemoembolization therapy (CET) of hepatocellular carcinoma (HCC) in rats. Materials and Methods Animal experiments were approved by the institutional animal care and use committee and performed from February 2014 to April 2015. Male Sprague-Dawley rats (n = 45; age, 12 weeks) were inoculated with N1S1 HCC cells in the liver, and 8 days later, were randomly divided into two groups of 10 rats. Group 1 rats received intrahepatic arterial injection of PEG-HAuNS and ethiodized oil alone; group 2 received pretreatment with CA4P and injection of PEG-HAuNS and ethiodized oil 5 minutes later. The gold content of tumor and liver tissue at 1 hour or 24 hours after injection was quantified by using neutron activation analysis (n = 5 per time point). Five rats received pretreatment CA4P, PEG-copper 64-HAuNS, and ethiodized oil and underwent micro-positron emission tomography (PET)/computed tomography (CT). In a separate study, three groups of six rats with HCC were injected with saline solution (control group); CA4P, Dox-loaded PEG-coated HAuNS (Dox@PEG-HAuNS), and ethiodized oil (CET group); or CA4P, Dox@PEG-HAuNS, ethiodized oil, and near-infrared irradiation (PTA-CET group). Temperature was recorded during laser irradiation. Findings were verified at postmortem histopathologic and/or autoradiographic examination. Wilcoxon rank-sum test and Pearson correlation analyses were performed. Results PEG-HAuNS uptake in CA4P-pretreated HCC tumors was significantly higher than that in non-CA4P-pretreated tumors at both 1 hour (P < .03) and 24 hours (P < .01). Mean ± standard deviation of tumor-to-liver PEG-HAuNS uptake ratios at 1 hour and 24 hours, respectively, were 5.63 ± 3.09 and 1.68 ± 0.77 in the CA4P-treated group and 1.29 ± 2.40 and 0.14 ± 0.11 in the non-CA4P-treated group. Micro-PET/CT allowed clear delineation of tumors, enabling quantitative imaging analysis. Laser irradiation increased temperature to 60°C and 43°C in the tumor and adjacent liver, respectively. Mean HCC tumor volumes 10 days after therapy were 1.68 cm3 ± 1.01, 3.96 cm3 ± 1.75, and 6.13 cm3 ± 2.27 in the PTA-CET, CET, and control groups, respectively, with significant differences between the PTA-CET group and other groups (P < .05). Conclusion CA4P pretreatment caused a higher concentration of Dox@PEG-HAuNS to be trapped inside the tumor, thereby enhancing the efficacy of anti-HCC treatment with PTA-CET in rats. © RSNA, 2016 Online supplemental material is available for this article.

[Clinical Characteristics of Wilson's Disease: a Retrospective Analysis of Admission Data among 126 Patients].

OBJECTIVE: To investigate the clinical features of Wilson's disease (WD) for the purpose of avoiding misdiagnosis and therefore improving the prognosis of this rare disease. METHODS: This study enrolled all the patients diagnosed as WD who were admitted to West China Hospital, Sichuan University from Jan 2008 to Dec 2014. Their clinical manifestations, head and abdominal images data were extracted and analyzed. RESULTS: There were a total of 126 patients of WD, male female ratio was 75 : 51, median age was 21-years old. 10.3% (13/126) of them had family history, 87.3% (109/126) patients presented with neuropsychiatric symptoms, 14.3% (18/126) patients manifested as chronic liver disease. All patients had decreased serum ceruloplasmin level < 200 mg/L, 121 (96.9%) patients had serum ceruloplasmin level < 100 mg/L. Magnetic resonance imaging and abdominal ultrasound detected structural abnormalities in 92.7% (102/110) and 88.9% (97/109) patients respectively. Kayser-Fleischer rings on slit-lamp ophthalmologic examination was found in 98.3% (115/117) patients. One patient underwent liver biopsy and the result of rhodanine stain was positive. The time from onset to diagnosis varied from 3 d to 19 years [(1.59 ± 2.66) years]. 20 (15.9%) patients were initially misdiagnosed. CONCLUSION: The patients presenting with neurological signs or unexplained liver disease should be assessed carefully for WD. Serum ceruloplasmin, 24-h urinary copper, Kayser-Fleischer rings and sometimes even liver biopsy could be helpful for the diagnosis.

[Diagnostic value of CT for head and neck pilomatricoma].

OBJECTIVE: To evaluate the CT and pathological features of head and neck pilomatricoma. METHODS: We retrospectively analyzed the CT findings of 13 patients with head and neck pilomatricoma which were pathologically confirmed. Of them 7 patients received plain CT, 2 patients received contrast-enhancement, and 4 patients received plain CT plus contrast-enhancement. RESULTS: All the patients presented with solitary tumors, 9 of them occurred in the parotid gland region, one in the left occipital, one in the right forehead, one in the right parietal, and another one in the left eyelid. The maximal diameter of the tumors ranged from 0.6 to 2.3 cm with a mean of 1.5 cm. All lesions were well-circumscribed, with partial attachment to the overlying skin. Most of lesions were isodense relative to adjacent skeletal muscle on non-enhanced CT scans, sand-like or nodular calcifications within the masses were showed in 8 cases, and no cystic degeneration was found. On contrast-enhanced imaging, mild to moderate homogenous enhancement was showed in 3 cases, heterogeneous moderate enhancement with patchy nonenhancing necrosis area in one case, marked enhancement in one case, and complete calcification with no enhancement in one case. CONCLUSION: Head and neck pilomatricoma presents with certain characteristics on CT, which are useful in the clinical diagnosis and differential diagnosis.

Nogo-B: A potential indicator for hepatic cirrhosis and regulator in hepatic stellate cell activation.

AIM: To evaluate plasma Nogo-B levels in liver cirrhotic patients and declare a novel molecular basis by which Nogo-B modulates hepatic stellate cell (HSC) activation. METHODS: Plasma Nogo-B levels from liver cirrhotic patients were detected by enzyme-linked immunosorbent assay. Rat primary HSC were culture activated or stimulated with transforming growth factor (TGF)-ß. Activated HSC were transfected for 48 h with Nogo-B shRNA to inhibit Nogo-B expression. Gene expressions of Nogo-B, α-smooth muscle actin (SMA), collagen type I, TGF-ß, endoplasmic reticulum (ER) stress key molecules, including C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78), activating transcription factor (ATF)4, ATF6, X-box binding protein 1 (Xbp-1) and calnexin, and the marker of autophagy beclin 1, were detected by quantitative reverse transcription polymerase chain reaction. The protein expressions of Nogo-B, α-SMA, collagen type I, CHOP, GRP78 and the marker of autophagy LC3B were evaluated by western blot. RESULTS: Liver cirrhotic patients showed a much higher level of plasma Nogo-B compared with the healthy controls. Nogo-B expression and ER stress could be induced during the process of cultured HSC activation. TGF-ß treatment increased Nogo-B expression time- and dose-dependently. Knockdown of Nogo-B in HSC reduced the activation of HSC. After Nogo-B gene knockdown, there was a decline of expression of ER stress markers and autophagic markers. Agonist or antagonist of ER stress could regulate autophagy level. CONCLUSION: Circulating Nogo-B may be an effective indicator for liver cirrhosis. Nogo-B inhibition could diminish HSC activation, in which alleviating ER stress may be one of the mechanisms, suggesting a potential approach to interference Nogo-B in liver fibrosis.

Value of diffusion-weighted magnetic resonance imaging on the follow-up of nasopharyngeal carcinoma after radiotherapy.

PURPOSE: To explore the value of diffusion-weighted imaging (DWI) and magnetic resonance imaging (MRI) on the follow-up of nasopharyngeal carcinoma (NPC) after radiotherapy. MATERIAL AND METHODS: Eighty-three NPC patients after radiotherapy were divided into two groups: 4 cases of residual tumor and 33 cases of non-residual within 6 months, the cases of recurrent and non-recurrent were 5 and 41 over 6 months, respectively. MRI and DWI imaging of these cases were closely analyzed, and the apparent diffusion coefficient (ADC) of the nasopharyngeal residual mass and nasopharyngeal wall thickening, skull base destruction and lateral pterygoid muscle were measured. RESULTS: The ADC of the lateral pterygoid muscle was (1.501 ± 0.069) × 10^{ - 3} mm^{2}/s in 83 cases. The ADCs of the non-residual group, residual group, non-recurrent group and recurrent group were (1.843 ± 0.133.4) × 10^{ - 3} mm^{2}/s, (1.097 ± 0.183) × 10^{ - 3} mm^{2}/s, (1.884 ± 0.134) × 10^{ - 3} mm^{2}/s and (0.787 ± 0.067) × 10^{ - 3} mm^{2}/s respectively.The ADCs of the residual group and recurrent group were lower than that of the lateral pterygoid muscle, while the ADCs of the non-residual group and non-recurrent group were higher than that of the lateral pterygoid muscle.The differences were statistically significant (P < 0.05). CONCLUSION: DWI can provide qualitative and quantitative information about the tumor cellular level; it can also identify residual, local fibrosis and recurrence after NPC radiotherapy sensitively and accurately by measuring the ADC of the region of interest.

Detection of uric acid depositing in tophaceous gout using a new dual energy spectral CT technology.

OBJECTIVE: To assess the feasibility and diagnostic value of detecting uric acid depositing among patients with tophaceous gout using a dual energy CT based Gemstone spectral imaging (GSI) technology for qualitative analysis of uric acid. METHODS: Thirty one patients with clinically detectable tophaceous gout and 10 healthy volunteers underwent Discovery CT 750 HD scan with GSI mode. We selected four case groups of tophi, muscles, cortical bone, and cancellous bone. Each has a region of interest (ROI) of 10 mm diameter. We then analyzed and compared the difference of CT imaging spectroscopy quantitative parameters including concentration of uric acid, calcium, and water levels. The univariate analysis of variance and independent samples t-test were applied in data analyses. RESULTS: In case group of tophi base substance, the concentration levels were 1268.8 ± 32.2 mg/cm3 for uric acid (Ca), 19.4 ± 9.5 mg/cm3 for calcium (uric acid), 10.8 ± 9.5 mg/cm3 for calcium (water), and 1171.0 ± 26.8 mg/cm3 for water (calcium), respectively. In cortical bone case group, the four base substance concentration levels changed to 1333.6 ± 83.8 mg/cm3, 271.1 ± 85.0 mg/cm3, 262.6 ± 85.4 mg/cm3, and 1230.8 ± 77.0 mg/cm3. In muscles case group, the four base substance concentration levels were 1143.5 ± 15.7 mg/cm3,12.3 ± 5.0 mg/cm3, 4.4 ± 1.9 mg/cm3, and 1054.1 ± 14.6 mg/cm3. Finally, in cancellous bone case group, the corresponding base substance concentration became 1070.9 ± 26.4 mg/cm3, 85.1 ± 46.9 mg/cm3, 77.4 ± 46.7 mg/cm3, and 988.0 ± 23.4 mg/cm3. Except tophi and muscle differences between Calcium (uric acid) concentration and differences in Calcium (water) concentration, which were not significantly different (p> 0.29), the remaining group pairwise comparisons of the parameters were significantly different (p < 0.05). CONCLUSION: Dual-energy spectral CT can detect gout tophi within the peripheral joints of the patients. The quantitative measurement of the tophi concentration provides a new imaging method for quantitatively monitoring clinical outcomes of tophi.

Correlation between CT attenuation value and iodine concentration in vitro: discrepancy between gemstone spectral imaging on single-source dual-energy CT and traditional polychromatic X-ray imaging.

INTRODUCTION: To assess the relation between CT attenuation value and iodine concentration in vitro, using gemstone spectral imaging (GSI) with single-source dual-energy CT and traditional polychromatic X-ray imaging (TPXI), respectively. METHODS: A polypropylene phantom with eight test tubes in which iodine concentrations of solution were 0.4, 0.7, 2, 5, 10, 20, 30 and 50 mg/mL underwent GSI and traditional polychromatic X-ray scans (80, 100, 120 and 140 kV(p)), using single-source dual-energy spectral CT (Discovery CT750HD; GE Healthcare Technologies, Milwaukee, WI, USA) at the same tube speed of 0.8 s/rotation. All spectral imaging data were analysed with GSI viewer to obtain monochromatic images (50-140 keV, interval of 10 keV). Computed tomography attenuation values of iodine solution were measured with the same size of regions of interest and at the exact same level for both monochromatic and polychromatic images. The relation between CT attenuation value and iodine concentration was examined. RESULTS: A linear correlation was found between CT attenuation value and iodine concentration for both monochromatic and polychromatic images. Moreover, the fitting coefficients for CT attenuation values and iodine concentrations were closer to one with GSI (r(2) = 0.99824-0.99996) than that with TPXI (r(2) = 0.99640-0.99736). CONCLUSIONS: Owing to the better correlation coefficients between CT attenuation value and iodine concentration, GSI may be a preferred method for quantitative measurement compared with TPXI.

A study of CT monochromatic imaging for quantitative detecting hemoglobin levels.

PURPOSE: The purpose of this study was to investigate the value of spectral CT monoenergetic imaging for detecting hemoglobin levels. MATERIAL AND METHODS: Sixty-five hospitalized patients received chest non-contrast CT scan in gemstone spectral imaging (GSI) mode on a GE Discovery CT750 HD. This study was approved by the hospital ethics committee and informed consent was signed by every patient. Raw data were reconstructed at 1.25 mm and then transferred to a AW4.4 workstation. The CT value of the ascending aorta at 40 keV∼140 keV was measured under GSI viewer of AW4.4. Hemoglobin contents were measured biochemically within 24 hrs after CT scan. The SPSS 16.0 software package was used to analyze the correlation between the obtained CT value and hemoglobin level. RESULTS: At 40 keV ∼ 100 keV, the CT value decreased followed by the increase of keV and gradually stabilized at 100 keV ∼ 140 keV with an amplitude variation of 10 HU. The CT values measured at 40 keV ∼ 140 keV were well correlated with hemoglobin levels. The optimal correlation was observed at the monoenergetic level of 70 keV (r=0.633, p=0.000). The relationship between CT value and hemoglobin content could be expressed as CT value=13.015+0.245 × hemoglobin content. At 40 keV ∼ 140 keV, there is strong linear correlation between the CT value of the ascending aorta and hemoglobin content. The optimal linear relationship was observed at 70 keV. CONCLUSION: Spectral CT monoenergetic imaging can be applied for quantitative determination of hemoglobin content within a specified area of the circulatory system.

Hepatic veno-occlusive disease after taking Gynura Rhizome: The value of multidetector computed tomography in diagnosing the disease and evaluating the clinical therapeutic effect.

AIM: We conducted this study to evaluate the role of multidetector computed tomography (MDCT) in diagnosing and differential diagnosis hepatic veno-occlusive disease (HVOD), and as well as assessing the clinical therapeutic effects. METHODS: From 2007 to 2010, 10 inpatients with weight increasing, liver pains, ascites, jaundice and history of taking gynura rhizome before hospitalization were scanned with a 64-MDCT. The data were reconstructed every 0.625 mm and reviewed using multiplanar reconstruction (MPR) and liver CT angiography (CTA) on a GE AW4.2 workstation. Patients were re-scanned with MDCT after medication so that the clinical therapeutic effect could be evaluated before the patients discharging from hospital. RESULTS: In 10 HVOD patients, the diagnoses of MDCT were coincident with clinical results. All patients had ascites and pleural fluid, hepatomegaly except the caudate lobe in MDCT. Failure to view hepatic veins in hepatic 3 phase scans, but portal veins and inferior vena cava were unobstructed. In portal-phase, hepatic enhancements were non-uniform. Three patients were incorrectly diagnosed before hospital admission. All patients improved significantly after hepato-protection and supporting therapy. No ascites, hydrothorax, hepatomegaly and obstruction of hepatic veins were observed by MDCT before patients were discharged from hospital. CONCLUSION: Multidetector computed tomography combined with MPR and liver CTA images are helpful in the diagnosis and differential diagnosis of HVOD and in the evaluation of clinical therapeutic effects.