Exploration of anatomical distribution of brain metastasis from breast cancer at first diagnosis assisted by artificial intelligence.

Objectives: This study aimed to explore the spatial distribution of brain metastases (BMs) from breast cancer (BC) and to identify the high-risk sub-structures in BMs that are involved at first diagnosis. Methods: Magnetic resonance imaging (MRI) scans were retrospectively reviewed at our centre. The brain was divided into eight regions according to its anatomy and function, and the volume of each region was calculated. The identification and volume calculation of metastatic brain lesions were accomplished using an automatically segmented 3D BUC-Net model. The observed and expected rates of BMs were compared using 2-tailed proportional hypothesis testing. Results: A total of 250 patients with BC who presented with 1694 BMs were retrospectively identified. The overall observed incidences of the substructures were as follows: cerebellum, 42.1 %; frontal lobe, 20.1 %; occipital lobe, 9.7 %; temporal lobe, 8.0 %; parietal lobe, 13.1 %; thalamus, 4.7 %; brainstem, 0.9 %; and hippocampus, 1.3 %. Compared with the expected rate based on the volume of different brain regions, the cerebellum, occipital lobe, and thalamus were identified as higher risk regions for BMs (P value ≤ 5.6*10-3). Sub-group analysis according to the type of BC indicated that patients with triple-negative BC had a high risk of involvement of the hippocampus and brainstem. Conclusions: Among patients with BC, the cerebellum, occipital lobe and thalamus were identified as higher-risk regions than expected for BMs. The brainstem and hippocampus were high-risk areas of the BMs in triple negative breast cancer. However, further validation of this conclusion requires a larger sample size.

Radiological distribution of brain metastases and its implication for the hippocampus avoidance in whole brain radiotherapy approach.

OBJECTIVE: Hippocampus avoidance in whole brain radiotherapy (HA-WBRT) offers the feasibility of less-impaired cognitive function than conventional WBRT. The study aims to assess the radiological distribution of brain metastases (BMs) with relation to the hippocampus and peri-hippocampus region as defined by the RTOG 0933 for better understanding of margin definition in HA-WBRT treatment planning. METHODS: Consecutive patients with diagnosis of BM from enhanced MRI between March 2011 and July 2016 were analysed. The pre-treatment T1 weighted, T2 weighted, T2 flair, three-dimensional spoiled gradient axial and contrast-enhanced axial cranial MR images of 226 patients are examined. The closest distances between the edge of hippocampus and the margin of tumours on different planes were measured. RESULTS: A total of 226 patients with 1080 visible metastatic sites were reviewed. The origin of the primary tumors was in 72.6% lung (n = 164), in 45 cases (19.9%) breast cancer and in 7.5% other malignancies (n = 17). There were 758 (70.2%) lesions situated beyond the tentorium. The median size of single lesion was 13.9 ± 14.7 mm. Impossible, it seems that more of the patients are with only one lesion, to verify. The hippocampus involvement was found in 3.1% (n = 7, 95% CI 0.01-0.05) within 5 mm, 5.7% (n = 13, 95% CI 0.03-0.09) within 10mm and 8.4% (n = 19, 95% CI 0.05-0.12) within 20 mm. In multivariate analysis, the number 6 BM or higher was found to be an independent risk factor for hippocampal involvement (HI) (OR: 5.2, 5.38 and 3.84 in 5, 10 and 20 mm). CONCLUSION: This radiological study found that the incidence of hippocampus involvement is low in patients with BM. HA-WBRT can be delivered under the context of complete radiological diagnosis after careful delineation, proper margin definition and individual planning optimization. Advances in knowledge: The incidence of HI in patients with initial diagnosis of BM from solid tumours impacts the radiotherapeutic decision. Our radiological data analysed the incidence of HI not only to the conventional 5 mm margin definition, but also expanded to wider margins as 10 and 20 mm from hippocampus, which will help the treatment planning optimization with different technique.

Three-dimensional Contrast-enhanced Ultrasound in Response Assessment for Breast Cancer: A Comparison with Dynamic Contrast-enhanced Magnetic Resonance Imaging and Pathology.

To compare the capabilities of three-dimensional contrast enhanced ultrasound (3D-CEUS) and dynamic contrast-enhanced magnetic resonance (DCE-MRI) in predicting the response to neoadjuvant chemotherapy (NAC) among breast cancer patients, 48 patients with unilateral breast cancer were recruited for 3D-CEUS and DCE-MRI examinations both before and after NAC; pathology was used to validate the results. This study was approved by the institutional review board, and written informed consent was obtained from each patient. Imaging feature changes and pathological vascularity response, including microvessel density (MVD) and vascular endothelial growth factor (VEGF), were calculated. Pathological complete response (pCR) and major histological response (MHR) were used as references. The 3D-CEUS score, DCE-MRI score, MVD and VEGF significantly decreased (P < 0.0001) after NAC. The correlations between Δ3D-CEUS and ΔDCE-MRI with pCR (r = 0.649, P < 0.0001; r = 0.639, P < 0.0001) and MHR (r = 0.863, P < 0.0001; r = 0.836, P < 0.0001) were significant. All scores showed significant differences between the pCR and non-pCR groups with folder changes of 0.1, 0.1, 2.4, and 2.3, respectively (P = 0.0001, <0.0001, <0.0001 and <0.0001). In conclusion, 3D-CEUS is effective in assessing the response of breast cancer patients undergoing NAC.

Molecular evaluation of thrombosis using X-ray phase contrast imaging with microbubbles targeted to P-selectin in mice.

OBJECTIVES: X-ray phase contrast imaging (PCI) provides excellent image contrast by utilizing the phase shift. The introduction of microbubbles into tissues can cause a phase shift to make microbubbles visibly identified on PCI. In this study, we assessed the feasibility of targeted microbubble-based PCI for the detection of thrombosis. METHODS: The absorption and phase contrast images of P-selectin-targeted microbubbles (MBP) were obtained and compared in vitro. MBP, control IgG-targeted microbubbles (MBC), and unbound microbubbles (MBU) were tested for binding specificity on thrombi expressing P-selectin. MBP were used as molecular PCI probes to evaluate P-selectin expression in a mouse model of arteriovenous shunt thrombosis that was created using PE tubes in the bypass outside of the mouse body. RESULTS: PCI clearly showed the microbubbles not viewable via absorption contrast imaging (ACI). In vitro attachment of MBP (91.60 ± 11.63) to thrombi was significantly higher than attachment of MBC (17.80 ± 4.02, P < 0.001) or MBU (9.80 ± 2.59, P < 0.001). In the mouse model of arteriovenous shunt thrombosis, the binding affinity of MBP (15.50 ± 6.25) was significantly greater than that of MBC (0.50 ± 0.84, P < 0.001) or MBU (0.33 ± 0.52, P < 0.001). CONCLUSIONS: Our results indicate that molecular PCI may be considered as a novel and promising imaging modality for the investigation of thrombosis. KEY POINTS: • Small thrombi are rarely detected by conventional radiography. • Phase contrast imaging (PCI) provides higher contrast and spatial resolution than conventional radiography. • P-selectin targeted microbubbles detected by PCI may suggest early thrombosis.

A novel imaging tool for hepatic portal system using phase contrast technique with hydrogen peroxide-generated O2 gas.

The objective of this study was to investigate the potential of hydrogen peroxide-generated oxygen gas-based phase contrast imaging (PCI) for visualizing mouse hepatic portal veins. The O2 gas was made from the reaction between H2O2 and catalase. The gas production was imaged by PCI in real time. The H2O2 was injected into the enteric cavity of the lower sigmoid colon to produce O2 in the submucosal venous plexus. The generated O2 gas could be finally drained into hepatic portal veins. Absorption contrast imaging (ACI) and PCI of O2-filled portal veins were performed and compared. PCI offers high resolution and real-time visualization of the O2 gas production. Compared with O2-based ACI, O2-based PCI significantly enhanced the revealing of the portal vein in vivo. It is concluded that O2-based PCI is a novel and promising imaging modality for future studies of portal venous disorders in mice models.

Dual-Energy CT for Patients Suspected of Having Liver Iron Overload: Can Virtual Iron Content Imaging Accurately Quantify Liver Iron Content?

PURPOSE: To prospectively assess the feasibility of using virtual iron content (VIC) imaging at dual-energy computed tomography (CT) to evaluate the liver iron content (LIC) in patients suspected of having liver iron overload and to compare the LIC grading performance of VIC imaging and magnetic resonance (MR) imaging. MATERIALS AND METHODS: This study was approved by the institutional review board, and informed consent was obtained from all patients. Fifty-six patients suspected of having liver iron overload (serum ferritin concentrations >500 µg/L) underwent unenhanced dual-energy CT and MR imaging of the liver. MR imaging-measured LICs were obtained in 34 of the 56 patients. VIC images were generated with dual-energy analysis. R2* and MR-measured LIC were obtained with gradient-echo and spin-echo sequences, respectively. Correlations between CT and MR measurements were analyzed. The diagnostic performance of VIC and R2* in the differentiation of different LIC thresholds were evaluated with receiver operating characteristic (ROC) analysis. RESULTS: Hepatic VIC showed significant correlation with R2* and MR-measured LIC (r = 0.885 and 0.871, respectively; P < .0001). To differentiate among different LIC thresholds of 1.8, 3.2, 7.0, and 15.0 mg of iron per gram of dry tissue, the corresponding optimal cutoff values for VIC were 2.50, 5.13, 8.93, and 17.97 HU, respectively. At a LIC threshold of 7.0 mg of iron per gram of dry tissue or higher, 100% sensitivity (15 of 15 patients) and 100% specificity (19 of 19 patients) were obtained for VIC. There was no significant difference between VIC and R2* (area under the ROC curve, 0.964 vs 0.993, respectively; P = .299) in grading LIC levels at a LIC threshold of 3.2 mg of iron per gram of dry tissue or higher. Conclusion Hepatic VIC is a potential index for accurately evaluating and grading clinically significant liver iron accumulation, with a diagnostic performance similar to that of MR imaging.

Virtual iron concentration imaging based on dual-energy CT for noninvasive quantification and grading of liver iron content: An iron overload rabbit model study.

OBJECTIVES: To assess the accuracy of liver iron content (LIC) quantification and grading ability associated with clinical LIC stratification using virtual iron concentration (VIC) imaging on dual-energy CT (DECT) in an iron overload rabbit model. METHODS: Fifty-one rabbits were prepared as iron-loaded models by intravenous injection of iron dextran. DECT was performed at 80 and 140 kVp. VIC images were derived from an iron-specific algorithm. Postmortem LIC assessments were conducted on an inductively coupled plasma (ICP) spectrometer. Correlation between VIC and LIC was analyzed. VIC were stratified according to the corresponding clinical LIC thresholds of 1.8, 3.2, 7.0, and 15.0 mg Fe/g. Diagnostic performance of stratification was evaluated by receiver operating characteristic analysis. RESULTS: VIC linearly correlated with LIC (r = 0.977, P < 0.01). No significant difference was observed between VIC-derived LICs and ICP (P > 0.05). For the four clinical LIC thresholds, the corresponding cutoff values of VIC were 19.6, 25.3, 36.9, and 61.5 HU, respectively. The highest sensitivity (100%) and specificity (100 %) were achieved at the threshold of 15.0 mg Fe/g. CONCLUSIONS: Virtual iron concentration imaging on DECT showed potential ability to accurately quantify and stratify hepatic iron accumulation in the iron overload rabbit model. KEY POINTS: • Virtual iron concentration (VIC) linearly correlates with liver iron content (LIC). • VIC accurately quantifies LIC. • VIC accurately grades LIC based on clinical LIC stratification.

Three-dimensional contrast enhanced ultrasound score and dynamic contrast-enhanced magnetic resonance imaging score in evaluating breast tumor angiogenesis: correlation with biological factors.

OBJECTIVE: To explore the clinical value of three-dimensional contrast enhanced ultrasound (3D-CEUS) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) score systems in evaluating breast tumor angiogenesis by comparing their diagnostic efficacy and correlation with biological factors. METHODS: 3D-CEUS was performed in 183 patients with breast tumors by Esaote Mylab90 with SonoVue (Bracco, Italy), DCE-MRI was performed on a dedicated breast magnetic resonance imaging (DBMRI) system (Aurora Dedicated Breast MRI Systems, USA) with a dedicated breast coil. 3D-CEUS and DCE-MRI score systems were created based on tumor perfusion and vascular characteristics. Microvessel density (MVD), vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP-2, MMP-9) expression were measured by immunohistochemistry. RESULTS: Pathological results showed 35 benign and 148 malignant breast tumors. MVD (P=0.000, r=0.76), VEGF (P=0.000, r=0.55), MMP-2 (P=0.000, r=0.39) and MMP-9 (P=0.000, r=0.41) expression were all significantly different between benignity and malignancy. Regarding 3D-CEUS 4 points as cutoff value, the sensitivity, specificity and accuracy were 85.1%, 94.3% and 86.9%, respectively, and correlated well with MVD (P=0.000, r=0.50), VEGF (P=0.000, r=0.50), MMP-2 (P=0.000, r=0.50) and MMP-9 (P=0.000, r=0.66). Taking DCE-MRI 5 points as cutoff value, the sensitivity, specificity and accuracy were 86.5%, 94.3% and 88.0%, respectively and also correlated well with MVD (P=0.000, r=0.52), VEGF (P=0.000, r=0.44), MMP-2 (P=0.000, r=0.42) and MMP-9 (P=0.000, r=0.35). CONCLUSIONS: 3D-CEUS score system displays inspiring diagnostic performance and good agreement with DCE-MRI scoring. Moreover, both score systems correlate well with MVD, VEGF, MMP-2 and MMP-9 expression, and thus have great potentials in tumor angiogenesis evaluation.

Detection of small hepatocellular carcinoma using gadoxetic acid-enhanced MRI: Is the addition of diffusion-weighted MRI at 3.0T beneficial?

OBJECTIVE: To determine whether adding diffusion-weighted imaging (DWI) to gadoxetic acid-enhanced 3.0T magnetic resonance imaging (MRI) can improve the detection of hepatocellular carcinoma (HCC), particularly for small lesions (≤2 cm) in patients with liver cirrhosis. METHODS: Data of patients diagnosed with focal liver lesions who had undergone gadoxetic acid-enhanced 3.0T MRI and DWI were retrospectively reviewed. Two radiologists (the observers) reviewed independently MRI images in two reading sessions, that is, gadoxetic acid-enhanced images alone and the combination of DWI (b values: 0 and 600 s/mm(2) ) and gadoxetic acid-enhanced images. They assigned to each lesion a confidence level based on a five-point scale. The area under the receiver operating characteristic curve (AUROC), sensitivity and positive predictive value (PPV) for the detection of HCC were calculated. RESULTS: Both observers found the AUROC of the gadoxetic acid-enhanced images was slightly higher than that of the combined DWI and gadoxetic acid-enhanced MRI images in the detection of HCC (observer 1: 0.947 ± 0.030 vs 0.896 ± 0.042, Z = 1.478, P = 0.139; observer 2: 0.917 ± 0.038 vs 0.868 ± 0.048, Z = 1.296, P = 0.195). The sensitivity for the gadoxetic acid set alone was slightly higher than that for the combined set for observer 1 (97% vs 84%) and slightly lower for observer 2 (74% vs 82%). The PPVs were slightly higher for the gadoxetic acid set alone than for the combined set for both observers (observer 1, 89% vs 80%; observer 2, 93% vs 78%); however, none of the differences were statistically significant (P > 0.05). CONCLUSION: There is no benefit in adding DWI to gadoxetic acid-enhanced MRI for the detection of HCC at 3.0T.

In-line phase contrast imaging of hepatic portal vein embolization with radiolucent embolic agents in mice: a preliminary study.

It is crucial to understand the distribution of embolic agents inside target liver during and after the hepatic portal vein embolization (PVE) procedure. For a long time, the problem has not been well solved due to the radiolucency of embolic agents and the resolution limitation of conventional radiography. In this study, we first reported use of fluorescent carboxyl microspheres (FCM) as radiolucent embolic agents for embolizing hepatic portal veins. The fluorescent characteristic of FCM could help to determine their approximate location easily. Additionally, the microspheres were found to be fairly good embolizing agents for PVE. After the livers were excised and fixed, they were imaged by in-line phase contrast imaging (PCI), which greatly improved the detection of the radiolucent embolic agents as compared to absorption contrast imaging (ACI). The preliminary study has for the first time shown that PCI has great potential in the pre-clinical investigation of PVE with radiolucent embolic agents.

CO2-based in-line phase contrast imaging of small intestine in mice.

The objective of this study was to explore the potential of CO2 single contrast in-line phase contrast imaging (PCI) for pre-clinical small intestine investigation. The absorption and phase contrast images of CO2 gas production were attained and compared. A further increase in image contrast was observed in PCI. Compared with CO2-based absorption contrast imaging (ACI), CO2-based PCI significantly enhanced the detection of mucosal microstructures, such as pits and folds. The CO2-based PCI could provide sufficient image contrast for clearly showing the intestinal mucosa in living mice without using barium. We concluded that CO2-based PCI might be a novel and promising imaging method for future studies of gastrointestinal disorders.

[MRI outstands mammogram in sensitivity of breast ductal carcinoma in situ:an analysis of 122 cases].

OBJECTIVES: To compare the sensitivity of mammogram and breast dedicated MRI in detecting ductal carcinoma in situ with microinvaion (DCIS-MI) and ductal carcinoma in situ (DCIS) lesions, and to further investigate the independent predictive factors of mammogram and MRI sensitivity. METHODS: From August 2009 to November 2011, 122 consecutive confirmed breast cancer patients who had received operations were recruited for this clinical research. These patients were divided into two groups including DCIS (72 cases) and DCIS-MI (50 cases) based on pathologic reports. All the patients were female, with mean ages of 52.6 years and 54.4 years. Preoperative bilateral breast mammogram, breast dedicated MRI depictions and reports as well as histopathological reports were collected. RESULTS: Sensitivity of MRI outstood mammogram in each subgroups: 84.7% vs. 42.4% in DCIS (χ(2) = 27.028, P = 0.000), 94.0% vs. 80.0% in DCIS-MI group (χ(2) = 4.540, P = 0.040). And further analysis showed that MRI was more sensitive to high nuclear grade DCIS and DCIS-MI lesions than low nuclear grade ones (OR = 3.471, P = 0.031). RESULTS: of logistic regression analysis proved microcalcification was an independent predictive factor of mammogram sensitivity (OR = 11.287, P = 0.001). CONCLUSIONS: Sensitivity of breast dedicated MRI is superior to mammogram in detecting DCIS and DCIS-MI groups. Lesions with microcalcifiation is an independent predictive marker which meant that mammogram would achieve high detection rate in cancers presented calcification on mammogram image when compared with non-calcification. Diagnostic performance of breast MRI is less affected by clinical and pathological characteristics of the early stage breast cancer patients but further increased detection rate is observed in DCIS and DCIS-MI with high nuclear grade lesions which indicated that MRI could detect more early stage cancers with relative more aggression biological behaviour and provide these patients with early surgical interventions before possible progression to invasive breast cancers.

X-ray phase contrast imaging of cell isolation with super-paramagnetic microbeads.

Super-paramagnetic microbeads are widely used for cell isolation. Evaluation of the binding affinity of microbeads to cells using optical microscopy has been limited by its small scope. Here, magnetic property of microbeads was first investigated by using synchrotron radiation (SR) in-line x-ray phase contrast imaging (PCI). The cell line mouse LLC (Lewis lung carcinoma) was selected for cell adhesion studies. Targeted microbeads were prepared by attaching anti-VEGFR2 (vascular endothelial growth factor receptor-2) antibody to the shell of the microbeads. The bound microbeads were found to better adhere to LLC cells than unbound ones. PCI dynamically and clearly showed the magnetization and demagnetization of microbeads in PE-50 tube. The cells incubated with different types of microbeads were imaged by PCI, which provided clear and real-time visualization of the cell isolation. Therefore, PCI might be considered as a novel and efficient tool for further cell isolation studies.

Accuracy of physical examination, ultrasonography, and magnetic resonance imaging in predicting response to neo-adjuvant chemotherapy for breast cancer.

BACKGROUND: Accurate evaluation of response following chemotherapy treatment is essential for surgical decision making in patients with breast cancer. Modalities that have been used to monitor response to neo-adjuvant chemotherapy (NAC) include physical examination (PE), ultrasound (US), and magnetic resonance imaging (MRI). The purpose of this study was to evaluate the accuracy of PE, US, and MRI in predicting the response to NAC in patients with breast cancer. METHODS: According to the response evaluation criteria in solid tumors guidelines, the largest unidimensional measurement of the tumor diameter evaluated by PE, US, and MRI before and after NAC was classified into four grades, including clinical complete response, clinical partial response, clinical progressive disease, clinical stable disease, and compared with the final histopathological examination. RESULTS: Of the 64 patients who received NAC, the pathologic complete response (pCR) was shown in 13 of 64 patients (20%). The sensitivity of PE, US, and MRI in predicting the major pathologic response was 73%, 75%, and 80%, respectively, and the specificity was 45%, 50%, and 50% respectively. For predicting a pCR, the sensitivity of PE, US, and MRI was 46%, 46%, and 39%, respectively, and the specificity was 65%, 98%, and 92% respectively. CONCLUSIONS: Compared with final pathologic findings, all these three clinical and imaging modalities tended to obviously underestimate the pCR rate. A more appropriate, universal, and practical standard by clinical and imaging modalities in predicting the response to neo-adjuvant chemotherapy in vivo is essential.

Anti-VEGFR2-conjugated PLGA microspheres as an x-ray phase contrast agent for assessing the VEGFR2 expression.

The primary goal of this study was to evaluate the feasibility of using anti-vascular endothelial growth factor receptor 2 (VEGFR2)-conjugated poly(lactic-co-glycolic acid) (PLGA) microspheres as an x-ray phase contrast agent to assess the VEGFR2 expression in cell cultures. The cell lines, mouse LLC (Lewis lung carcinoma) and HUVEC (human umbilical vein endothelial cell), were selected for cell adhesion studies. The bound PLGA microspheres were found to better adhere to LLC cells or HUVECs than unbound ones. Absorption and phase contrast images of PLGA microspheres were acquired and compared in vitro. Phase contrast imaging (PCI) greatly improves the detection of the microspheres as compared to absorption contrast imaging. The cells incubated with PLGA microspheres were imaged by PCI, which provided clear 3D visualization of the beads, indicating the feasibility of using PLGA microspheres as a contrast agent for phase contrast CT. In addition, the microspheres could be clearly distinguished from the wall of the vessel on phase contrast CT images. Therefore, the approach holds promise for assessing the VEGFR2 expression on endothelial cells of tumor-associated vessels. We conclude that PLGA microsphere-based PCI of the VEGFR2 expression might be a novel, promising biomarker for future studies of tumor angiogenesis.

Microbubble-based synchrotron radiation phase contrast imaging: basic study and angiography applications.

The purpose of the study was to evaluate the feasibility of microbubbles as phase contrast imaging (PCI) agents for angiography applications. The hypothesis was that the introduction of microbubbles into tissue produces a significant change in the refractive index and highlights the lumen of the vessel in PCI. The absorption and phase contrast images of commercially available microbubbles were obtained and compared in vitro. A further increase in contrast was observed in PCI. Microbubbles highlighted the lumen of the renal microvessels, acting as a positive contrast medium in ex vivo imaging. In addition, home-made microbubbles with larger diameters were introduced for image contrast enhancement in living tumor-bearing mice, demonstrating the feasibility of microbubble-based x-ray phase-contrast imaging for tumor vasculature in vivo.

MR Imaging of activated hepatic stellate cells in liver injured by CCl4 of rats with integrin-targeted ultrasmall superparamagnetic iron oxide.

OBJECTIVE: To demonstrate the feasibility of the ultrasmall superparamagnetic iron oxide (USPIO) modified by cyclo (Arg-Gly-Asp-Try-Cys) peptide (c(RGDyC)-USPIO) for targeting hepatic stellate cells (HSCs). MATERIALS AND METHODS: A c(RGDyC)-USPIO probe was prepared by conjugating c(RGDyC) with USPIO through a thiol-maleinide interaction. The specificity of c(RGDyC)-USPIO for HSCs was investigated in vitro. In vivo, normal and fibrosis rats were treated with either c(RGDyC)-USPIO or USPIO, and magnetic resonance imaging (MRI) of the rats performed after administration of the probes for 4 h. The T2 relaxation times changes before and after probe injection were analyzed and the locations of probes in normal or injured mice were identified histologically. RESULTS: The hydrodynamic size of c(RGDyC)-USPIO was 13 ± 3 nm. HSCs took up more specific probes than plain ones. The reduction of T2 relaxation times in fibrosis rat by c(RGDyC)-USPIO was much greater than that by USPIO (P < 0.05). Prussian blue staining and transmission electron microscopy of the injured rat liver treated with c(RGDyC) demonstrated that c(RGDyC)-USPIO were specifically engulfed by the activated HSCs. CONCLUSION: In vivo cellular targeted imaging of activated HSCs in liver fibrosis using c(RGDyC)-USPIO targeting α(v)ß(3) integrins was feasible using a clinical 1.5-Tesla MR system.

Hepatitis B virus-induced liver fibrosis and cirrhosis: the value of liver and spleen volumetry with multi-detector spiral computed tomography.

OBJECTIVE: To study the correlation of liver and spleen volume with the degree of liver fibrosis and cirrhosis induced by hepatitis B virus infection. METHODS: 128 participants who had undergone liver and spleen volumetry were enrolled. The control group consisted of 41 participants who were potential living liver donors. The liver fibrosis group consisted of 63 histologically proved liver fibrosis patients who were further divided into two subgroups: 44 patients with slight liver fibrosis, and 19 patients with advanced liver fibrosis. The liver cirrhosis group consisted of 24 patients. The following parameters were determined by multi-detector spiral computed tomography (MSCT) examination: total liver volume (TLV), right liver lobe volume (RV), left lateral liver segment volume (LLV), left medial liver segment volume (LMV), caudate lobe volume (CV), and spleen volume (SV). The ratios of CV to TLV (C/T), RV to TLV (R/T), LLV to TLV (LL/T), LMV to TLV (LM/T), and SV to TLV (S/T) were calculated. RESULTS: TLV, RV, LMV tended to decrease and SV, C/T, S/T tended to increase gradually with the increased degree of fibrosis. C/T >or= 3.34% and S/T >or= 47.36% were identified as the cut-off values of fibrosis >or=F3 (advanced liver fibrosis) and cirrhosis, respectively. Their sensitivities were 68.4% and 87.5% and their specificities were 59.1% and 89.5%, respectively. CONCLUSION: Variations in liver and spleen volume correlated with the degree of liver fibrosis and cirrhosis and could be used in the non-invasive follow-up of the development of liver fibrosis.

Correlation of iron in the hippocampus with MMSE in patients with Alzheimer's disease.

PURPOSE: To investigate the brain iron deposits in patients with Alzheimer's disease (AD) and healthy age-matched controls using phase imaging. MATERIALS AND METHODS: Twenty-six AD patients and 24 healthy controls were recruited. A three-dimensional high-resolution, gradient-echo sequence was used to acquire phase data in the coronal plane. A high-pass filter was used to remove the phase variation caused by field inhomogeneity. The regions evaluated included the bilateral putamen, globus pallidus, and the head and body of the hippocampus. RESULTS: Significantly lower phase values in both the basal ganglion and hippocampus were revealed in the AD group compared to the normal controls (P < 0.05). The phase value in the right side of the head of the hippocampus had a moderate positive correlation with the MMSE score (r= 0.603, P = 0.000) and a negative correlation with the duration of the disease (r = -0.677, P = 0.013). Using -0.0972 radians as an optimal cutoff value, the sensitivity and specificity for differentiation between AD and normal controls reached 95.8 and 80.8%, respectively. CONCLUSION: Phase imaging proved to be a useful method for the differentiation between normal controls and AD patients. An investigation of the excessive accumulation of iron in the hippocampus may help us better understand the pathologic process and neuropsychological dysfunction of AD disease.

Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography.

AIM: To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential. METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P < 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6 cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly (P < 0.05). Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors. CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyma and nearby structures in SPTs of the pancreas can be accurately revealed by MDCT preoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.