Multi-modality parathyroid imaging:A shifting paradigm

The goal of parathyroid imaging in hyperparathyroidism is not diagnosis,rather it is the localization of the cause of hyperparathyroidism for planning the best therapeutic approach.Hence,the role of imaging to accurately and precisely localize the abnormal parathyroid tissue is more important than ever to facilitate minimally invasive parathyroidectomy over bilateral neck exploration.The common causes include solitary parathyroid adenoma,multiple parathyroid adenomas,parathyroid hyperplasia and parathyroid carcinoma.It is highly imperative for the radiologist to be cautious of the mimics of parathyroid lesions like thyroid nodules and lymph nodes and be able to differentiate them on imaging.The various imaging modalities available include high resolution ultrasound of the neck,nuclear imaging studies,four-dimensional computed tomography(4D CT)and magnetic resonance imaging.Contrast enhanced ultrasound is a novel technique which has been recently added to the armam-entarium to differentiate between parathyroid adenomas and its mimics.Through this review article we wish to review the imaging features of parathyroid lesions on various imaging modalities and present an algorithm to guide their radiological differentiation from mimics.

Multi-modality imaging of cardiac amyloidosis: Contemporary update

Cardiac amyloidosis is a heterogeneous and challenging diagnostic disease with poor prognosis that is now being altered by introduction of new therapies.Echocardiography remains the first-line imaging tool, and when disease is suspected on echocardiography, cardiac magnetic resonance imaging and nuclear imaging play critical roles in the non-invasive diagnosis and evaluation of cardiac amyloidosis. Advances in multi-modality cardiac imaging allowing earlier diagnosis and initiation of novel therapies have significantly improved the outcomes in these patients. Cardiac imaging also plays important roles in the risk stratification of patients presenting with cardiac amyloidosis. In the current review, we provide a clinical and imaging focused update, and importantly outline the imaging protocols, diagnostic and prognostic utility of multimodality cardiac imaging in the assessment of cardiac amyloidosis.

Diagnostic and prognostic value of cardiac imaging in amyloidosis

Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years.Different types of amyloidosis can affect the heart.Transthyretin amyloidosis and light chain amyloidosis are the two most common types of cardiac amyloidosis.These entities have a poor prognosis,so accurate diagnostic techniques are imperative for determining an early therapeutic approach.Recent advances in cardiac imaging and diagnostic strategies show that these tools are safe and can avoid the use of invasive diagnostic techniques to histological confirmation,such as endomyocardial biopsy.We performed a review on the diagnostic and prognostic implications of different cardiac imaging techniques in cardiac amyloidosis.We mainly focus on reviewing echocardiography,cardiac magnetic resonance,computed tomography and nuclear imaging techniques and the different safety measurements that can be done with each of them.

Revascularization and outcomes in Veterans with moderate to severe ischemia on myocardial perfusion imaging

Background: The prevalence of ischemia on nuclear myocardial perfusion imaging(MPI) has been decreasing. Recent research has questioned the benefit of invasive revascularization for patients with moderate to severe ischemia. We hypothesized that patients with moderate to severe ischemia could routinely undergo successful revascularization.Methods: We analyzed data from 544 patients who underwent an MPI at a single academic Veterans Affairs Medical Center. Patients with moderate to severe ischemia, defined as a summed difference score(SDS) 8 or greater, were compared to the rest of the cohort.Results: Of the total cohort(n=544), 39 patients had MPI studies with resultant moderate to severe ischemia. Patients with ischemia were more likely to develop coronary artery disease(74.4% versus 38.8%, P<0.0001) and have successful revascularization(38.5% versus 4.0%, P<0.0001) during the following year. Revascularization was attempted in 31 patients with moderate to severe ischemia, though only 15(47%) of these attempts were successful. Ischemia was predictive of myocardial infarction(5.1% versus 0.8%, P=0.01) within 1 year.Conclusion: Moderate to severe ischemia is an uncommon finding in a contemporary nuclear laboratory. Among patients with ischemia, revascularization is typically attempted but is frequently unsuccessful.Trial registration: This trial does not appear on a registry as it is neither randomized nor prospective.

SAR image de-noising based on texture strength and weighted nuclear norm minimization

As synthetic aperture radar（SAR） has been widely used nearly in every field, SAR image de-noising became a very important research field. A new SAR image de-noising method based on texture strength and weighted nuclear norm minimization（WNNM） is proposed. To implement blind de-noising, the accurate estimation of noise variance is very important. So far, it is still a challenge to estimate SAR image noise level accurately because of the rich texture. Principal component analysis（PCA） and the low rank patches selected by image texture strength are used to estimate the noise level. With the help of noise level, WNNM can be expected to SAR image de-noising. Experimental results show that the proposed method outperforms many excellent de-noising algorithms such as Bayes least squares-Gaussian scale mixtures（BLS-GSM） method, non-local means（NLM） filtering in terms of both quantitative measure and visual perception quality.

In-situ observation and modeling approach to evolution of pore-fracture structure in coal

The characterisation of the pore-fracture structure(PFS)and its evolution in coal during mining are essential for preventing gas outbursts and improving gas extraction efficiency.In this study,the evolution of the PFS in coal samples under the condition of mining stress was directly captured in situ by combination of the mechanical testing system with high-precision visualisation nuclear magnetic resonance equipment.A fractional derivative model was established to describe the relationship between stress and porosity based on experimental results of the PFS under different stress states.The results showed that with an increase in the deviatoric stress,the adsorption pore content increases rapidly initially and then increases slowly or remains unchanged;the seepage pore and fracture(SPF)content decreases initially and then increases.The SPF compressibility coefficient decreases with an increase in the deviatoric stress.The fractional derivative model can accurately describe the stress sensitivity of the SPFs at the pre-peak stage,thus providing a new approach for accurately characterising the seepage characteristics of coal reservoirs.

Multimodality image fusion for diagnosing coronary artery disease

Coronary artery disease （CAD） is one of the leading causes of death in the US and a substantial health-care burden in all industrialized societies. In recent years we have witnessed a constant strive towards the development and the clinical application of novel or improved detection methods as well as therapies. Particularly, noninvasive imaging is a decisive component in the cardiovascular field. Image fusion is the ability of combining into a sin- gle integrated display the anatomical as well as the physiological data retrieved by separated modalities. Clinical evidence suggests that it represents a promising strategy in CAD assessment and risk stratification by significantly improving the diagnostic power of each modality independently considered and of the traditional side-by-side in- terpretation. Numerous techniques and approaches taken from the image registration field have been implemented and validated in the context of CAD assessment and management. Although its diagnostic power is widely ac- cepted, additional technical developments are still needed to become a routinely used clinical tool.

Imbibition characteristics of sandstone cores with different permeabilities in nanofluids

The core imbibition and shifting nuclear magnetic resonance(NMR) imaging experiment has loss of surface oil phase and air adsorption, which will affect the accuracy of the experiment result. To solve this issue, a modified experiment method, in-situ imbibition NMR method has been worked out. This method was used to carry out sandstone core imbibition experiment in nanofluid, and the oil migration images in the entire process were recorded. In combination with physical properties of the sandstone cores and the variations of the driving force during the imbibition process, imbibition characteristics of the sandstone cores with different permeabilities in nanofluid were analyzed. The results show that: the nanofluid can greatly reduce the interfacial tension of oil phase and improve the efficiency of imbibition and oil discharge, the higher the concentration, the lower the interfacial tension and the higher the efficiency of imbibition and oil discharge would be, but when the concentration reaches a certain value, the increase in imbibition and oil discharge efficiency slows down;the rise of temperature can reduce the oil viscosity resistance and interfacial tension, and hence enhance the imbibition and oil discharge rate;when the sandstone core is higher in permeability, the bottom crude oil would migrate upward and discharge during the imbibition, the higher the permeability of the sandstone core, the more obvious this phenomenon would be, and the phenomenon is shown as top oil discharge characteristic;when the sandstone core is low in permeability, the crude oil in the outer layer of the sandstone core would discharge first during the imbibition, then crude oil in the inside of the core would disperse outside and discharge, which is shown as oil discharge characteristic around the core;but under long time effect of nanofluid, the core would become more and more water-wet and reduce in the oil-water interfacial tension, so would have top oil discharge characteristic in the later stage of imbibition.

^(188)Re-LABELED HYPERBRANCHED POLYSULFONAMINE AS A ROBUST TOOL FOR TARGETED CANCER DIAGNOSIS AND RADIOIMMUNOTHERAPY

Hyperbranched polysulfonamine （HPSA） is a promising biomaterial due to its highly branched spherical architecture and efficient intracellular translocation. To realize the fianctionalization of HPSA, both N-succinimidyl 3-（2- pyridyldithio） propionate （SPDP） for tethering the human-mouse chimeric monoclonal antibody CH12 and N-hydroxy succinimidyl S-acetylmercaptoacetyltriglycinate （NHS-MAG3） for labeling 188Re were sequentially grafted onto the primary amine terminals of HPSA via covalent linkages, attaining the SPDP-HPSA-MAG3 intermediate. In order to reserve the structural integrity of CH12, the fragment crystallizable （Fc） region was also processed by oxidation of oligosaccharide moieties with sodium periodate and then reacted with N-（κ-maleimidoundecanoic acid） hydrazide （KMUH）. After chelating 188Re with MAG3 group, the SPDP was reduced to PDP and connected onto the maleinimide group at the Fc region. As a result, both the epidermal growth factor receptor viii （EGFRvIII） targeted monoclonal antibody CH12 and the radionuclide 188Re were conjugated to the HPSA-based vehicles, forming the 188Re-labeled and CH12-tethered HPSA （CH12-HPSA- 188Re）. The molecular weight and in vitro stability of CH12-HPSA-188Re were evaluated by gel electrophoresis and paper chromatography. On one hand, the CH12-HPSA-188Re could specifically bind to the EGFRvlII-positive human hepatocarcinoma cells in vitro. On the other hand, it could also target at the tumor tissue of nude mice in vivo. Hence, the CH12-HPSA-188Re could effectively target at the human hepatocarcinoma and facilitate the tumor detection and targeted radioimmunotherapy.

The potential clinical applications of radionuclide labeled/doped gold-based nanomaterials

Radionuclides have been widely used for multimodal imaging and radioisotope therapy of cancer.Various nanomaterials have been developed as excellent nanocarriers of radionuclides for the targeted delivery into tumors,in order to minimize the unnecessary side effect and enhance the therapeutic efficacy of radiotherapy.Among those nanomaterials,gold nanomaterials with tunable morphologies,easy modification,good biological safety,and radiation sensitization capability are excellent candidates for cancer theranostics.Given the superior performance of gold-based nanomaterials in biomedicine,we summary the recent advance of radionuclide labeled/doped gold-based nanomaterials for cancer theranostics.In this review article,we will discuss the methods for labelling or doping radionuclides onto gold nanomaterials,their applications for nuclear imaging and Cerenkov luminescence(CL)imaging,as well as the radioisotope therapy of cancer,and finally the toxicity evaluation of radionuclide labeled/doped gold-based nanomaterials.We hope that our review article would provide guidance for non-experts to design the radiolabeled nanomaterials for cancer imaging guided therapy.