Carotid artery stiffness evaluated early by wave intensity in normal left ventricular function in post-radiotherapy patients with nasopharyngeal carcinoma

Purpose

This study aims to assess carotid elasticity early in normal left ventricular function in post-radiotherapy patients with nasopharyngeal carcinoma (NPC) by wave intensity.

Methods

Sixty-seven post-radiotherapy patients all with normal left ventricular function were classified into group NPC1 and group NPC2 based on their carotid intima-media thickness. Thirty age- and sex-matched NPC patients without any history of irradiation and chemotherapy were included as a control group. Carotid parameters, including stiffness constant (β), pressure–strain elastic modulus (Ep), arterial compliance (AC), stiffness constant pulse wave velocity (PWVβ), and wave intensity pulse wave velocity (PWVWI) were measured.

Results

There were no significant differences in conventional echocardiographic variables among the three groups. In comparison with the control group, β, Ep, PWVβ, and PWVWI were significantly increased, while AC was significantly decreased in the NPC1 and NPC2 groups, and there were differences between the NPC1 group and NPC2 group (all P < 0.05).

Conclusion

This study suggested that carotid artery stiffness increased with reduced carotid compliance in post-RT with NPC.

     

Detection of Lymph Node Metastases with SERRS Nanoparticles

Purpose

The accurate detection of lymph node metastases in prostate cancer patients is important to direct treatment decisions. Our goal was to develop an intraoperative imaging approach to distinguish normal from metastasized lymph nodes. We aimed at developing and testing gold-silica surface-enhanced resonance Raman spectroscopy (SERRS) nanoparticles that demonstrate high uptake within normal lymphatic tissue and negligible uptake in areas of metastatic replacement.

Procedures

We evaluated the ability of SERRS nanoparticles to delineate lymph node metastases in an orthotopic prostate cancer mouse model using PC-3 cells transduced with mCherry fluorescent protein. Tumor-bearing mice (n?=?6) and non-tumor-bearing control animals (n?=?4) were injected intravenously with 30 fmol/g SERRS nanoparticles. After 16–18 h, the retroperitoneal lymph nodes were scanned in situ and ex vivo with a Raman imaging system and a handheld Raman scanner and data corroborated with fluorescence imaging for mCherry protein expression and histology.

Results

The SERRS nanoparticles demonstrated avid homing to normal lymph nodes, but not to metastasized lymph nodes. In cases where lymph nodes were partially infiltrated by tumor cells, the SERRS signal correctly identified, with sub-millimeter precision, healthy from metastasized components.

Conclusions

This study serves as a first proof-of-principle that SERRS nanoparticles enable high precision and rapid intraoperative discrimination between normal and metastasized lymph nodes.

     

Evaluation of the impact of computed high <Emphasis Type="Italic">b</Emphasis>-value diffusion-weighted imaging on prostate cancer detection

Purpose

The purpose of this study was to compare high b-value (b = 2000 s/mm²) acquired diffusion-weighted imaging (aDWI) with computed DWI (cDWI) obtained using four diffusion models—mono-exponential (ME), intra-voxel incoherent motion (IVIM), stretched exponential (SE), and diffusional kurtosis (DK)—with respect to lesion visibility, conspicuity, contrast, and ability to predict significant prostate cancer (PCa).

Methods

Ninety four patients underwent 3 T MRI including acquisition of b = 2000 s/mm² aDWI and low b-value DWI. High b = 2000 s/mm² cDWI was obtained using ME, IVIM, SE, and DK models. All images were scored on quality independently by three radiologists. Lesions were identified on all images and graded for lesion conspicuity. For a subset of lesions for which pathological truth was established, lesion-to-background contrast ratios (LBCRs) were computed and binomial generalized linear mixed model analysis was conducted to compare clinically significant PCa predictive capabilities of all DWI.

Results

For all readers and all models, cDWI demonstrated higher ratings for image quality and lesion conspicuity than aDWI except DK (p < 0.001). The LBCRs of ME, IVIM, and SE were significantly higher than LBCR of aDWI (p < 0.001). Receiver Operating Characteristic curves obtained from binomial generalized linear mixed model analysis demonstrated higher Area Under the Curves for ME, SE, IVIM, and aDWI compared to DK or PSAD alone in predicting significant PCa.

Conclusion

High b-value cDWI using ME, IVIM, and SE diffusion models provide better image quality, lesion conspicuity, and increased LBCR than high b-value aDWI. Using cDWI can potentially provide comparable sensitivity and specificity for detecting significant PCa as high b-value aDWI without increased scan times and image degradation artifacts.

     

Value of diffusion-weighted MRI and apparent diffusion coefficient measurements for predicting the response of locally advanced rectal cancer to neoadjuvant chemoradiotherapy

Purpose

The aim of our study was to assess the performance value of magnetic resonance imaging (MRI) in the restaging of locally advanced rectal cancer after neoadjuvant chemoradiotherapy (CRT) and in the identification of good vs. poor responders to neoadjuvant therapy.

Materials and Methods

A total of 34 patients with locally advanced rectal cancer underwent MRI prior to and after CRT. T stage and tumor regression grade (TRG) on post-CRT MRI was compared with the pathological staging ypT and TRG. Tumor volume and the apparent diffusion coefficient (ADC) were measured using diffusion-weighted imaging (DWI) before and after neoadjuvant CRT; the percentage of tumor volume reduction and the change of ADC (ΔADC) was also calculated. ADC parameters and the percentage of tumor volume reduction were correlated to histopathological results. The diagnostic performance of ADC and volume reduction to assess tumor response was evaluated by calculating the area under the ROC curve and the optimal cut-off values.

Results

A significant correlation between the T stage and the TRG defined in DW-MRI after CRT and the ypT and the TRG observed on the surgical specimens was found (p = 0.001; p < 0.001). The mean post-CRT ADC and ΔADC in responder patients was significantly higher compared to non-responder ones (p = 0.001; p = 0.01). Furthermore, the mean post-CRT ADC values were significantly higher in tumors with T-downstage (p = 0.01).

Conclusion

DW-MRI may have a significant role in the restaging and in the evaluation of post-CRT response of locally advanced rectal cancer. Quantitative analysis of DWI through ADC map may result in a promising noninvasive tool to evaluate the response to therapy.

     

MRI characteristics of proctitis in Crohn’s disease on perianal MRI

Purpose

Multiple features have been described for assessing inflammation in Crohn’s disease (CD) in MR enterography, but have not been validated in perianal magnetic resonance imaging (MRI). Retrospectively, we studied which MRI features are valuable in assessing proctitis.

Materials and methods

CD patients (≥18 years) who underwent colonoscopy (reference standard) and perianal fistula MRI within 8 weeks were included. Seventeen MRI features were blindly scored by three observers and correlated to endoscopy (regression analysis). Reproducibility (multirater kappa, intraclass correlation coefficient) was determined for all three observer pairs. MRI features were considered relevant when significantly correlated to endoscopy for ≥2 observers, and reproducibility was ≥0.40 for ≥2 observer pairs.

Results

Perianal MRI of 58 CD patients were included. Wall thickness, rectal mural fat, creeping fat, and size of mesorectal lymph nodes showed a significant correlation with endoscopy for ≥2 observers (p = 0.000–0.023, p = 0.011–0.172, p = 0.007–0.011 and p = 0.000–0.005, respectively) with a kappa/intraclass correlation coefficient of ≥0.60 for ≥2 observer pairs. Perimural T2 signal and perimural enhancement significantly correlated to endoscopy (all p values ≤0.05) for all three observers and the reproducibility was ≥0.40 for ≥2 observer pairs. Mural T2 signal and degree and pattern of T1 enhancement showed significant correlation to endoscopy for two observers, but with poor to moderate reproducibility.

Conclusion

Wall thickness, mural fat, and mesorectal features (perimural T2 signal, perimural enhancement, creeping fat, and size of mesorectal lymph nodes) had significant correlation to endoscopy and were reproducible in diagnosing proctitis. Some established luminal features in MRE were considered not useful.

     

The Effect of Evolving Strategies in the Surgical Management of Organ-Confined Prostate Cancer: Comparison of Data from 2005 to 2014 in a Multicenter Setting

Introduction

The objective of this study was to evaluate changes of patient characteristics and surgical techniques in radical prostatectomy in Germany within the last decade.

Methods

Data from 44 German prostate cancer centers were included in the study. Patients’ characteristics (age, initial PSA value), surgical techniques (open vs. minimally invasive approaches), perioperative parameters (operating time, rate of nerve-sparing (NS) radical prostatectomies (RPs), hospitalization time, catheter indwelling time, surgical margin status, number of dissected lymph nodes (LN)), and pathological findings (tumor stage, Gleason score) were analyzed.

Results

Data from 11,675 patients who underwent RP between 2005 and 2014 were analyzed. The rate of open RP approaches decreased by 1.7% (p = 0.0164), the rate of minimally invasive approaches increased by 1.8% (p = 0.0164). Robot-assisted RPs (RARP) increased by 4.6% (p < 0.0001). The number of NS procedures and pelvic lymphadenectomy (LA) increased by 4.5% (p < 0.0001) and 4.7% (p < 0.0001), respectively. Catheter indwelling time and hospitalization time decreased by 1 day (p < 0.0001). No change in the rate of positive surgical margins (p = 0.5061) and the ratio of positive lymph nodes removed (p = 0.4628) was observed. The number of Gleason ≤6 tumors decreased significantly (p < 0.0001).

Conclusions

The number of RARP has significantly increased over the past decade and there is a trend towards surgeries on more advanced tumors with higher yields of lymph nodes dissected. At the same time, the rate of nerve-sparing procedures has significantly increased.

     

Facile Synthesis of Folic Acid-Modified Iron Oxide Nanoparticles for Targeted MR Imaging in Pulmonary Tumor Xenografts

Purpose

The purpose of this study was to develop folic acid (FA)-modified iron oxide (Fe₃O₄) nanoparticles (NPs) for targeted magnetic resonance imaging (MRI) of H460 lung carcinoma cells.

Procedures

Water-dispersible Fe₃O₄ NPs synthesized via a mild reduction method were conjugated with FA to generate FA-targeted Fe₃O₄ NPs. The specificity of FA-targeted Fe₃O₄ NPs to bind FA receptor was investigated in vitro by cellular uptake and cell MRI and in vivo by MRI of H460 tumors.

Results

The formed NPs displayed good biocompatibility and ultrahigh r ₂ relaxivity (440.01/mM/s). The targeting effect of the NPs to H460 cells was confirmed by in vitro cellular uptake and cell MRI. H460 tumors showed a significant reduction in T₂ signal intensity at 0.85 h, which then recovered and returned to control at 2.35 h.

Conclusions

The results indicate that the prepared FA-targeted Fe₃O₄ NPs have potential to be used as T₂ negative contrast agents in targeted MRI.

     

Detection of Enzyme Activity and Inhibition during Studies in Solution, <Emphasis Type="Italic">In Vitro</Emphasis> and <Emphasis Type="Italic">In Vivo</Emphasis> with CatalyCEST MRI

Purpose

The detection of enzyme activities and evaluation of enzyme inhibitors have been challenging with magnetic resonance imaging (MRI). To address this need, we have developed a diamagnetic, nonmetallic contrast agent and a protocol known as catalyCEST MRI that uses chemical exchange saturation transfer (CEST) to detect enzyme activity as well as enzyme inhibition.

Procedures

We synthesized a diamagnetic MRI contrast agent that has enzyme responsive and enzyme unresponsive CEST signals. We tested the ability of this agent to detect the activity of kallikrein 6 (KLK6) in biochemical solutions, in vitro and in vivo, with and without a KLK6 inhibitor.

Results

The agent detected KLK6 activity in solution and also detected KLK6 inhibition by antithrombin III. KLK6 activity was detected during in vitro studies with HCT116 colon cancer cells, relative to the detection of almost no activity in a KLK6-knockdown HCT116 cell line and HCT116 cells treated with antithrombin III inhibitor. Finally, strong enzyme activity was detected within an in vivo HCT116 tumor model, while lower enzyme activity was detected in a KLK6 knockdown tumor model and in the HCT116 tumor model treated with antithrombin III inhibitor. In all cases, comparisons of the enzyme responsive and enzyme unresponsive CEST signals were critical for the detection of enzyme activity.

Conclusions

This study has established that catalyCEST MRI with an exogenous diaCEST agent can evaluate enzyme activity and inhibition in solution, in vitro and in vivo.

     

Targeted Superparamagnetic Iron Oxide Nanoparticles for <Emphasis Type="Italic">In Vivo</Emphasis> Magnetic Resonance Imaging of T-Cells in Rheumatoid Arthritis

Purpose

The purpose of the study is to develop a targeted nanoparticle platform for T cell labeling and tracking in vivo.

Procedures

Through carboxylation of the polyethylene glycol (PEG) surface of SPION, carboxylated-PEG-SPION (IOPC) was generated as a precursor for further conjugation with the targeting probe. The IOPC could readily cross-link with a variety of amide-containing molecules by exploiting the reaction between 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide and N-hydroxysuccinimide. The subsequent conjugation of monoclonal anti-CD3 antibody with IOPC made it possible to construct a magnetic resonance imaging (MRI) contrast agente (CA) that targets T cells, named IOPC-CD3.

Results

IOPC-CD3 was found to have high transverse relaxivity, good targeting selectivity, and good safety profile in vitro. The utility of this newly synthesized CA was explored in an in vivo rodent collagen-induced arthritis (CIA) model of rheumatoid arthritis. Serial MRI experiments revealed a selective decrease in the signal-to-noise ratio of the femoral growth plates of CIA rats infused with IOPC-CD3, with this finding being consistent with immunohistochemical results showing the accumulation of T cells and iron oxide nanoparticles in the corresponding region.

Conclusions

Together with the abovementioned desirable features, these results indicate that IOPC-CD3 offers a promising prospect for a wide range of cellular and molecular MRI applications.

     

Vascular ultrasound in pediatrics: utility and application of location and measurement of jugular and femoral vessels

Objective

To measure the depth (D _p) and diameter (D _m) of the internal jugular vein (IJV), femoral vein (FV), and femoral artery (FA) in pediatric patients to evaluate the clinical implications.

Methods

This study included 125 pediatric patients. All of them underwent bilateral ultrasound study of vessels and were classified into three groups based on anthropometric and demographic parameters.

Results

Measured mean D _p values were: 0.72 (0.34) cm for the FA, 0.79 (0.35) cm for the FV, and 0.77 (0.24) cm for the IJV. Mean antero-posterior D _m values were: 0.37 (0.17) cm for the FA, 0.42 (0.22) cm for the FV, and 0.59 (0.23) cm for the IJV. D _p and D _m increased with age (A), weight (W), height (H), and body surface area (BSA). In the lower ranges of these variables, D _p was similar for all three studied vessels (0.6–0.7 cm). In the higher ranges, femoral vessel D _p values (1.1–1.2 cm) were larger than jugular ones (0.9 cm). Additionally, in these low ranges, IJV D _m values were larger than femoral ones (0.45–0.50 vs. 0.25 cm). In the higher ranges, diameter values were similar (0.6–0.7 cm).

Conclusions

In pediatric patients, major vessels can be located and their depth and diameter measured by vascular ultrasound. In younger patients, jugular and femoral vessels had similar depth values; in older ones, they had similar diameters. Ultrasound measurements in pediatric patients could facilitate the choice of the vessel to be cannulated, the catheter diameter, and the length of the needle to be used. Vascular canalization of IJV may be recommended as the first choice because of its low depth and large diameter.

     

Development of digital phantoms based on a finite element model to simulate low-attenuation areas in CT imaging for pulmonary emphysema quantification

Purpose

To develop an innovative finite element (FE) model of lung parenchyma which simulates pulmonary emphysema on CT imaging. The model is aimed to generate a set of digital phantoms of low-attenuation areas (LAA) images with different grades of emphysema severity.

Methods

Four individual parameter configurations simulating different grades of emphysema severity were utilized to generate 40 FE models using ten randomizations for each setting. We compared two measures of emphysema severity (relative area (RA) and the exponent D of the cumulative distribution function of LAA clusters size) between the simulated LAA images and those computed directly on the models output (considered as reference).

Results

The LAA images obtained from our model output can simulate CT-LAA images in subjects with different grades of emphysema severity. Both RA and D computed on simulated LAA images were underestimated as compared to those calculated on the models output, suggesting that measurements in CT imaging may not be accurate in the assessment of real emphysema extent.

Conclusions

Our model is able to mimic the cluster size distribution of LAA on CT imaging of subjects with pulmonary emphysema. The model could be useful to generate standard test images and to design physical phantoms of LAA images for the assessment of the accuracy of indexes for the radiologic quantitation of emphysema.

     

Bioluminescence Imaging of Colonization and Clearance Dynamics of <Emphasis Type="Italic">Brucella Suis</Emphasis> Vaccine Strain S2 in Mice and Guinea Pigs

Purpose

The goal of this study was to develop a plasmid-based lux bio-reporter for use to obtain in vivo images of Brucella suis vaccine strain 2 (B.suis S2) infection with high resolution and good definition.

Procedures

The pBBR-lux (pBBR1MCS-2-lxCDABE) plasmid that carries the luxCDABE operon was introduced into B. suis S2 by electroporation yielding B. suis S2-lux. The spatial and temporal transit of B. suis S2 in mice and guinea pigs was monitored by bioluminescence imaging.

Results

The plasmid pBBR-lux is stable in vivo and does not appear to impact the virulence or growth of bacteria. This sensitive luciferase reporter could represent B. suis S2 survival in real time. B. suis S2 mainly colonized the lungs, liver, spleen, and uterus in mice and guinea pigs as demonstrated by bioluminescence imaging.

Conclusion

The plasmid-based lux bioreporter strategy can be used to obtain high resolution in vivo images of B. suis S2 infection in mice and guinea pigs.

     

Performance of diffusion-weighted imaging,perfusion imaging,and texture analysis in predicting tumoral response to neoadjuvant chemoradiotherapy in rectal cancer patients studied with 3T MR: initial experience

Purpose

To determine the performance of texture analysis (TA), diffusion-weighted imaging, and perfusion MR (pMRI) in predicting tumoral response in patients treated with neoadjuvant chemoradiotherapy (CRT).

Methods

12 consecutive patients (8 females, 4 males, 63.2 ± 13.4 years) with rectal cancer were prospectively enrolled, and underwent pre-treatment 3T MRI. Treatment protocol consisted of neoadjuvant CRT with oxaliplatin and 5-fluorouracile. Unenhanced T2-weighted images TA (kurtosis), apparent diffusion coefficient (ADC), and pMRI parameters (Ktrans, Kep, Ve, IAUGC) were quantified by manually delineating a region of interest around the tumor outline. After CRT, all patients underwent complete surgical resection and the surgical specimen served as the gold standard. Receiver operating characteristic (ROC) curve analysis was performed to assess the discriminatory power of each quantitative parameter to predict complete response.

Results

Pathological complete response (pCR) was reported in six patients and partial response (PR) in three patients. Three patients were classified as non-responders (NR). Pre-treatment kurtosis was significantly lower in the pCR sub-group in comparison with PR + NR (p = .01). Among ADC and pMRI parameters, only Ve was significantly lower in the pCR sub-group compared with PR + NR (p = .01). A significant negative correlation between kurtosis and ADC (r = ?0.650, p = .022) was observed. Pre-treatment area under the ROC curves (AUC), to discriminate between pCR and PR + NR, was significantly higher for kurtosis (0.861, p = .001) and Ve (0.861, p = .003) compared to all other parameters. The optimal cutoff value for pre-treatment kurtosis and Ve was ≤0.19 (100% sensitivity, 67% specificity) and ≤0.311 (83% sensitivity, 83% specificity), respectively.

Conclusion

Pre-treatment kurtosis derived from T2w images and Ve from pMRI have the potential to act as imaging biomarkers of rectal cancer response to neoadjuvant CRT.

     

Effet des extraits de quelques plantes sur les bactéries pathogènes responsables de gastroentérites

Background

Phytochemicals are natural bioactive compounds that protect plants against the stress. These phytochemicals may also have other biological activities like, antibacterial activity.

Objective

The objective of this work is to study the antibacterial effect of aqueous and hydro-alcoholic extracts prepared from Thymus vulgaris, Aloysia triphylla, Pistacia lentiscus, Olea europaea leaves and Trigonella foenum-graecum seeds on some pathogenic bacteria responsible for gastroenteritis.

Result

The results obtained from the antibacterial effect showed a moderate activity against the strains studied with a diameters of inhibition zones ranging from 07.00 ± 0.8 to 16.00 ± 1.0 mm for aqueous extracts and vary between 07.00 ± 0.9 and 13.00 ± 1.0 mm for hydro-alcoholic extracts.

Conclusion

This study confirms the possibility of using these plants or components in the prevention of several diseases like, gastroenteritis.

     

<Emphasis Type="Italic">In Vivo</Emphasis> MR Imaging of Dual MRI Reporter Genes and Deltex-1 Gene-modified Human Mesenchymal Stem Cells in the Treatment of Closed Penile Fracture

Purpose

The purpose of this study was to investigate the feasibility of dual magnetic resonance imaging (MRI) reporter genes, including ferritin heavy subunit (Fth) and transferrin receptor (TfR), which provide sufficient MRI contrast for in vivo MRI tracking, and the Deltex-1 (DTX1) gene, which promotes human mesenchymal stem cell (hMSC) differentiation to smooth muscle cells (SMCs), to treat closed penile fracture (CPF).

Methods

Multi-gene co-expressing hMSCs were generated. The expression of mRNA and proteins was assessed, and the original biological properties of hMSCs were determined and compared. The intracellular uptake of iron was evaluated, and the ability to differentiate into SMCs was detected. Fifty rabbits with CPF were randomly transplanted with PBS, hMSCs, Fth-TfR-hMSCs, DTX1-hMSCs, and Fth-TfR-DTX1-hMSCs. In vivo MRI was performed to detect the distribution and migration of the grafted cells and healing progress of CPF, and the results were correlated with histology.

Results

The mRNA and proteins of the multi-gene were highly expressed. The transgenes could not influence the original biological properties of hMSCs. The dual MRI reporter genes increased the iron accumulation capacity, and the DTX1 gene promoted hMSC differentiation into SMCs. The distribution and migration of the dual MRI reporter gene-modified hMSCs, and the healing state of CPF could be obviously detected by MRI and confirmed by histology.

Conclusion

The dual MRI reporter genes could provide sufficient MRI contrast, and the distribution and migration of MSCs could be detected in vivo. The DTX1 gene can promote MSC differentiation into SMCs for the treatment of CPF and effectively inhibit granulation tissue formation.

     

Comparative 13-year meta-analysis of the sensitivity and positive predictive value of ultrasound,CT, and MRI for detecting hepatocellular carcinoma

Purpose

To compare the per-lesion sensitivity and positive predictive value (PPV) of ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI) for the diagnosis of hepatocellular carcinoma (HCC).

Materials and methods

The meta-analysis of sensitivity included 242 studies (15,713 patients); 116 studies (7492 patients) allowed calculation of PPV. Pooled per-lesion sensitivity and PPV for HCC detection were compared using empirical Bayes estimates of a beta-binomial model.

Results

The pooled per-lesion sensitivity and PPV of contrast-enhanced CT (73.6%, 85.8%) and gadolinium-enhanced MRI (77.5%, 83.6%) are not significantly different (P = 0.08, P = 0.2). However, if the hepatobiliary agent gadoxetate is used, MRI has significantly higher pooled per-lesion sensitivity and PPV (85.6%, 94.2%) than CT (P < 0.0001) or than MRI with other agents (P < 0.0001). Non-contrast-enhanced US has the lowest overall sensitivity and PPV (59.3%, 77.4%). Pooled per-lesion sensitivity and PPV of contrast-enhanced US (84.4%, 89.3%) are relatively high, but no contrast-enhanced US study used the most rigorous reference standards.

Conclusion

MRI utilizing the hepatobiliary agent gadoxetate has the highest overall sensitivity and PPV, and may be the single optimal method for diagnosis of HCC. Non-contrast-enhanced US has the lowest sensitivity and PPV. More rigorous reference standards are needed to compare the performance of contrast-enhanced US with CT and MRI. Differences in sensitivity and PPV between CT and conventional gadolinium-enhanced MRI are not statistically significant overall.

     

Prevalence of hepatic lesion types defined by T2-weighted and dynamic gadolinium-enhanced MR imaging in patients with metastasized neuroendocrine tumors

Purpose

Identifying liver metastases from neuroendocrine tumors (NETs) is a pretherapeutic challenge in patients who are candidates for liver resection. The aims of our study are to characterize and determine the frequency of different MRI characteristics of liver metastases caused by NETs in a lesion-by-lesion analysis and to determine the frequency of monomorphous and polymorphous metastases in a patient-by-patient analysis.

Methods

This retrospective study involved 47 patients with liver metastases arising from histologically confirmed NETs. In a lesion-by-lesion analysis, we classified these metastases according to their MRI characteristics as follows: hypervascular lesions with homogeneous or peripheral enhancement, hypovascular lesions, pure cystic lesions, and mixed solid/cystic lesions. In the patient-by-patient analysis, we distinguished patients whose metastases had the same MRI characteristics from patients with mixed lesion characteristics.

Results

A total of 376 metastases were analyzed. Of these, 84.3% (n = 317) were hypervascular, with 51.9% showing homogeneous enhancement and 32.4% (n = 122) showing peripheral enhancement. Another 7.4% (n = 28) were hypovascular, 5.3% (n = 20) were pure cystic, and 2.9% (n = 11) were mixed solid/cystic. After excluding three patients with solitary lesions, 40.9% of patients (n = 18) had mixed-type lesions, consisting of hypervascular lesions with either homogeneous or peripheral enhancement in 27.3% of cases (n = 12), while 59.1% of patients (n = 26) had identical lesions.

Conclusion

Approximately 15% of metastases have atypical MRI characteristics and are either hypovascular or cystic. Metastases with different MRI characteristics coexist in 40% of patients.

     

Reactive Oxygen Species Imaging in a Mouse Model of Inflammatory Bowel Disease

Purpose

Reactive oxygen species (ROS) are important contributors to inflammatory bowel disease (IBD); however, there are insufficient tools for their in vivo evaluation.

Procedures

To determine if a chemiluminescent ROS reporter, coelenterazine, would be a useful tool for the detection of immune cell activation, the macrophage cell line (RAW 264.7) was treated with phorbol myristate acetate (PMA). Additionally, coelenterazine was used to monitor the changes in ROS production over time in a mouse model of IBD.

Results

In vitro, coelenterazine enabled the dynamic monitoring of the RAW 264.7 cell oxidative burst. In vivo, there were early, preclinical, changes in the localization and magnitude of coelenterazine chemiluminescent foci.

Conclusions

Coelenterazine offers a high-throughput method for assessing immune cell activation in culture and provides a means for the in vivo detection and localization of ROS during IBD disease progression.

     

How to not miss alveolar echinococcosis in hepatic lesions suspicious for cholangiocellular carcinoma

Purpose

Hepatic alveolar echinococcosis (AE) resembles intrahepatic cholangiocarcinoma (ICC) on radiological imaging. The purpose of this study was to identify criteria to discriminate AE from ICC with CT and MR Imaging.

Methods

One hundred and sixteen imaging studies of 94 patients (CT n = 65; MRI n = 51) diagnosed with AE (n = 55) or ICC (n = 39) were retrospectively reviewed by two blinded radiologists for lesion features including enhancement pattern and matrix composition. A consensus read was conducted in cases of disagreement. Uni- and multivariate logistic regression with bootstrapping were used for analysis.

Results

Using CT, no or septal enhancement and calcification yielded the highest values of sensitivity/specificity (90.9%/90.6% and 81.8%/96.9%) for AE. Using MRI, no or septal enhancement and cystic components achieved the highest sensitivity/specificity (90.9%/100.0% and 84.8%/66.7%) for AE. Multivariate logistic regression identified the following strong independent predictors for AE: for MRI, no or septal enhancement (odds ratio [OR] 322.4; p < 0.001); for CT, no or septal enhancement and calcification (OR 35.9 and 42.5; p < 0.001 and p < 0.01, respectively). No or septal enhancement and calcification demonstrated the highest interreader agreement (>90%).

Conclusion

Enhancement characteristics and matrix calcifications offer the strongest discriminating potential between AE and ICC with a high sensitivity, specificity, and interreader agreement.