Conventional Imaging Technologies Research Articles

Reverse magnetic resonance tuning nanoplatform with heightened sensitivity for non-invasively multiscale visualizing ferroptosis-based tumor sensitization therapy

Ferroptosis-based therapy has garnered considerable attention for its ability to kill drug-resistant cancer cells. Consequently, it holds great significance to assess the therapeutic outcomes by monitoring ferroptosis-related biomarkers, which enables the provision of real-time pathological insights into disease progression. Nevertheless, conventional imaging technology suffers from limitations including reduced sensitivity and difficulty in achieving real-time precise monitoring. Here, we report a tumor acidic-microenvironment-responsive nanoplatform with “Reverse Magnetic Resonance Tuning (ReMRT)” property and effective combined chemodynamic therapy (CDT) through the loading of chemotherapeutic drugs. This reverse MR mapping change is correlated with iron ion, reactive oxygen species (ROS) generation and drug release, etc., contributing to the precise monitoring of chemo-CDT effectiveness. Furthermore, the ReMRT nanoplatform presents as a highly efficacious combined chemo-CDT agent, and when this nanoplatform is used in conjunction with the “Area Reconstruction” method, it can afford a significant sensitivity (95.1-fold) in multiscale visualization of therapeutic, compared with the conventional MR R1/R2 values. The high-sensitive biological quantitative imaging provides a novel strategy for MR-guided multiscale dynamic tumor-related ferroptosis therapy.

Imaging performance of portable and conventional ultrasound imaging technologies for ophthalmic applications.

The aim of this study was to evaluate the imaging capabilities of Butterfly iQ with conventional ophthalmic (piezoelectric) ultrasound (COU) for ophthalmic imaging. Custom phantom molds were designed and imaged with Butterfly iQ and COU to compare spatial resolution capabilities. To evaluate the clinical imaging performance of Butterfly iQ and COU, a survey containing pathological conditions from human subjects, imaged with both Butterfly iQ and COU probes, was given to three retina specialists and graded on image detail, resolution, quality, and diagnostic confidence on a ten-point Likert scale. Kruskal-Wallis analysis was performed for survey responses. Butterfly iQ and COU had comparable capabilities for imaging small axial and lateral phantom features (down to 0.1 mm) of high and low acoustic reflectivity. One of three retina specialists demonstrated a statistically significant preference for COU related to resolution, detail, and diagnostic confidence, but the remaining graders showed no significant preference for Butterfly iQ or COU across all sample images presented. The emergence of portable ultrasound probes offers an affordable alternative to COU technologies with comparable qualitative imaging resolution down to 0.1 mm. These findings suggest the value to further study the use of portable ultrasound systems and their utility in routine eye care.

Monolithic Perovskite-Silicon Dual-Band Photodetector for Efficient Spectral Light Discrimination.

Selective spectral discrimination of visible and near-infrared light, which accurately distinguishes different light wavelengths, holds considerable promise in various fields, such as automobiles, defense, and environmental monitoring. However, conventional imaging technologies suffer from various issues, including insufficient spatial optimization, low definition, and optical loss. Herein, a groundbreaking advancement is demonstrated in the form of a dual-band photodiode with distinct near-infrared- and visible-light discrimination obtained via simple voltage control. The approach involves the monolithic stacking integration of methylammonium lead iodide (MAPbI3) and Si semiconductors, resulting in a p-Si/n-phenyl-C61-butyric acid methyl ester/i-MAPbI3/p-spiro-MeOTAD (PNIP) device. Remarkably, the PNIP configuration can independently detect the visible and near-infrared regions without traditional optical filters under a voltage range of 3 to -3V. In addition, an imaging system for a prototype autonomous vehicle confirms the capability of the device to separate visible and near-infrared light via an electrical bias and practicality of this mechanism. Therefore, this study pushes the boundaries of image sensor development and sets the stage for fabricating compact and power-efficient photonic devices with superior performance and diverse functionality.

Clinical features and novel technologies for prehospital detection of intracerebral haemorrhage: a scoping review protocol

IntroductionThe detection of intracerebral haemorrhage (ICH) in the prehospital setting without conventional imaging technology might allow early treatment to reduce haematoma expansion and improve patient outcomes. Although ICH and ischaemic...

The dose-effect regularity of artificial dermis combined with growth factor in repair wound of luxation of the bone tendon

To investigate the treatment efficacy of the artificial dermis combined with growth factor surgery in patients with luxation of bone tendon (LBT). A total of 40 patients with LBT in our prospective clinical research are randomly allocated to following four groups: Control, low dose, medium dose, and high dose. The baseline characteristics, skin graft interval time, overage rate of regenerated tissue at bone and tendon, and visual estimation of patients were measured, which were then utilized to assess the treatment efficacy of the artificial dermis combined with growth factor surgery in LBT patients. Our outcomes indicated that the artificial dermis combined with growth factor surgery showed significantly less skin graft interval time, higher overage rate of regenerated tissue at bone and tendon, less Vancouver scar scale score compared to those treated by conventional imaging technology (all P < 0.05). It concludes that the artificial dermis combined with growth factor surgery can improve the treatment efficacy, and the medium dose growth factor is a promise dose to treat the patients with LBT.

Dual-source CT with metal sphere-tube for preoperative evaluation of patients with aortic valve disease treated by transcatheter aortic valve implantation

To predict the effects of Dual-source CT imaging technology for preoperative patients with transcatheter aortic valve implantation. This is a parallel, randomly allocated to following two groups: patients with the Dual-source CT imaging technology and with conventional imaging technology, and the clinical material from two groups patients with Aortic valve disease are collected, and the images quality between two group are assessed and then complications in one month after surgery are recorded by follow-up. Our outcomes show that patients by the Dual-source CT imaging technology show less complications compared to patients by conventional imaging technology and imaging quality is better than that in conventional imaging group. In addition, image noise, and contrast-to-noise ratio are also examined by Dual-source CT imaging. We can conclude that the Dual-source CT can effectively reduce the complications, and the Dual-source CT can predict effects of preoperative patients with Aortic valve disease and prevent the development of Aortic valve disease (AVD).

Polarization multiplexing scattering imaging

Imaging through scattering media, such as clouds, biological tissues, and seawater, has broad application prospects in transportation, medical diagnosis, and information technology. Researchers have proposed various techniques to obtain images from scattered light passing through the scattering media, among which speckle correlation imaging has developed rapidly. Speckle correlation imaging requires non-coherent light sources due to the requirement of memory effect. This requirement makes the imaging device complex, and the light source utilization rate low. Additionally, this method is limited in its application under the illumination of spatially coherent light sources. This paper proposes a new method of speckle correlation imaging based on the illumination of spatially coherent light, which is achieved by multiplexing different polarization direction speckle patterns, called polarization multiplexing scattering imaging. To achieve the decoherence of the light source, previous approaches have used a rotating scattering medium to generate time-varying speckle patterns that are integrated over the shutter time of the camera to eliminate coherent noise, or multiplexed wavelength-dependent speckle multiplexing to achieve this. This paper uses spatially incoherent light sources to obtain different polarization direction speckle patterns by rotating polarizers placed in the illumination path. These patterns are superimposed and averaged, and phase recovery algorithm is used to reconstruct the object image. This experiment uses Ping-Pang (PP) algorithm with fusion error reduction and hybrid input-output algorithm to reconstruct targets quickly and with high quality. The comparison of the reconstruction results of different numbers of reused speckle patterns demonstrates that using more speckle patterns can achieve better image quality. Compared with conventional speckle correlation imaging technology, the proposed method reduces the requirements of light sources, improves the utilization rate of light sources, and makes the device simpler and more compact. Experimental results show that this method is feasible and has strong environmental adaptability, which can expand the application scope of speckle correlation imaging methods.

Broadband Graphene Field-Effect Coupled Detectors: From Soft X-Ray to Near-Infrared

Here, we report a broadband graphene-silicon field-effect coupled detector (FCD) sensitive to photons spanning from soft X-ray to Near-Infrared region. Unlike traditional charge-coupled devices (CCD) relying on serial charge transfer between potential wells, the FCD integrates photo-sensing, charge integration, field-effect amplification, and random readout in one pixel. The charge integration in the potential well of the semiconductor substrate and field-effect coupled amplification in graphene transistor result in a highly sensitive broadband response. In the X-ray region, the device displays a high sensitivity of 1088 CGy <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">air</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−2</sup> and a fast response time < ~5 ms. Linear array imaging reveals the potential of our devices for array-based broadband imaging. Our FCD offers a viable strategy to monolithically integrate 2D materials into conventional solid-state imaging technology, exploring the next-generation broadband photodetectors for high-quality imaging and super vision technology.

Confocal laser endomicroscopy in gastro-intestinal endoscopy: technical aspects and clinical applications.

Confocal laser endomicroscopy (CLE) is an advanced endoscopic imaging technology that provides a magnified, cellular level view of gastrointestinal epithelia. In conjunction with topical or intravenous fluorescent dyes, CLE allows for an "optical biopsy" for real-time diagnosis. Two different CLE system have been used in clinical endoscopy, probe-based CLE (pCLE) and endoscope-based CLE (eCLE). Using pCLE, the device can be delivered: (I) into the luminal gastrointestinal tract through the working channel of standard endoscopes; (II) into extraluminal cystic and solid parenchymal lesions through an endoscopic ultrasound (EUS) needle; or (III) into the biliary system through an endoscopic retrograde cholangiopancreatography (ERCP) accessory channel. With eCLE, the probe is directly integrated into the tip of a conventional endoscope, however, these endoscopes are no longer commercially available. CLE has moderate to high diagnostic accuracy for neoplastic and inflammatory conditions through the gastrointestinal tract including: oesophageal, gastric and colonic neoplasia, pancreatic cysts and solid lesions, malignant pancreatobiliary strictures and inflammatory bowel disease. Some studies have demonstrated the diagnostic benefit of CLE imaging when combined with either conventional white light endoscopy or advanced imaging technologies. Therefore, optical biopsies using CLE can resolve diagnostic dilemmas in some cases where conventional imaging fails to achieve conclusive results. CLE could also reduce the requirement for extensive tissue sampling during surveillance procedures. In the future, CLE in combination with molecular probes, could allow for the molecular characterization of diseases and assess response to targeted therapy. However, the narrow field of view, high capital costs and specialized operator training requirements remain the main limitations. Future multi-center, randomized trials with a focus on conventional diagnostic applications, cost-effectiveness and standardized training will be required for definitive evidence. The objective of this review is to evaluate the technical aspects and current applications of CLE in patients with gastrointestinal and pancreatobiliary diseases and discuss future directions for this technique.

Characterizing Organelles in Live Stem Cells Using Label-Free Optical Diffraction Tomography.

Label-free optical diffraction tomography (ODT), an imaging technology that does not require fluorescent labeling or other pre-processing, can overcome the limitations of conventional cell imaging technologies, such as fluorescence and electron microscopy. In this study, we used ODT to characterize the cellular organelles of three different stem cells—namely, human liver derived stem cell, human umbilical cord matrix derived mesenchymal stem cell, and human induced pluripotent stem cell—based on their refractive index and volume of organelles. The physical property of each stem cell was compared with that of fibroblast. Based on our findings, the characteristic physical properties of specific stem cells can be quantitatively distinguished based on their refractive index and volume of cellular organelles. Altogether, the method employed herein could aid in the distinction of living stem cells from normal cells without the use of fluorescence or specific biomarkers.

Have conventional dental radiographs lost its charm to modern techniques?

For any dental implant procedure that is being carried out, the success will depend on a thorough pre-operative investigation. The quality, quantity and the volume of available bone at the planned implant site has to be assessed properly when planning a dental implant placement. When we speak of the fore-mentioned aspects pre-surgical imaging and its co-relation to clinical findings help assess the relation to the amount of bone available from underlying vital parts namely the sinus cavities, nasal floor, nerves, teeth and vessels. Different radiographic modalities have been advocated for its assessment. Intra Oral Peri-apical radiograph (two-dimensional) is one such modality that has lost its importance after the introduction of more advanced techniques like Cone Beam Tomography (three-dimensional). This article will help us understand how two-dimensional and three-dimensional imaging modalities go hand in hand while treating dental patients. It will also explain why the conventional imaging technologies are still required in this era of modern methods of imaging.

Super-resolution performance studies for orbital-angular-momentum-based imaging radar

ABSTRACT Vortex electromagnetic (EM) wave carrying orbital angular momentum (OAM), whose unique wavefront distribution exhibits angular diversity characteristics, which provides a richer degree of freedom for information modulation. Although several works have reported that the EM vortex imaging has superior performance in target detection and imaging with azimuthal super-resolution, the underlying physical mechanism needs to be further developed. This article offers a solution to significantly refine the imaging resolution for conventional real-aperture imaging radar (CRAIR) using multiple OAM-carrying beams. Firstly, it is deduced that the various spatial frequency distributions and time-varying phase wavefront distributions of OAM beams promote the realization of OAM-based imaging radar (OAMIR) super-resolution imaging. Secondly, a scheme for adjusting the directivity of EM vortex beam is proposed, which can effectively acquire most spatial frequency components of the probed target, resulting in the target can be illuminated simultaneously by the main lobes of various beams carrying different topological charges. Thirdly, the point-spread function (PSF) comparison for CRAIR and OAMIR is carried out by theoretical analysis and numerical simulation, and the spatial azimuth resolution for OAMIR is derived. Finally, the signal mathematical model for OAMIR is established and analysed. Simulation results validate that the proposed OAM-based imaging paradigm breaks through the Rayleigh limit associated with conventional real-aperture imaging technology and achieves imaging performance superior to OAMIR in previous works.

A Deep Learning Perspective on Dropwise Condensation.

Condensation is ubiquitous in nature and industry. Heterogeneous condensation on surfaces is typified by the continuous cycle of droplet nucleation, growth, and departure. Central to the mechanistic understanding of the thermofluidic processes governing condensation is the rapid and high‐fidelity extraction of interpretable physical descriptors from the highly transient droplet population. However, extracting quantifiable measures out of dynamic objects with conventional imaging technologies poses a challenge to researchers. Here, an intelligent vision‐based framework is demonstrated that unites classical thermofluidic imaging techniques with deep learning to fundamentally address this challenge. The deep learning framework can autonomously harness physical descriptors and quantify thermal performance at extreme spatio‐temporal resolutions of 300 nm and 200 ms, respectively. The data‐centric analysis conclusively shows that contrary to classical understanding, the overall condensation performance is governed by a key tradeoff between heat transfer rate per individual droplet and droplet population density. The vision‐based approach presents a powerful tool for the study of not only phase‐change processes but also any nucleation‐based process within and beyond the thermal science community through the harnessing of big data.

An Integrin-αvβ6/α5β1-Bitargeted Probe for the SPECT Imaging of Pancreatic Adenocarcinoma in Preclinical and Primary Clinical Studies.

Pancreatic adenocarcinoma (PA) is one of the deadliest human malignancies. However, early detection, prediction of surgical resectability, and prognosis of PA are challenging with current conventional imaging technologies in the clinic. Molecular imaging technologies combined with novel imaging probes could be useful for early detection and accurate staging of PA. Integrin αvβ6 and α5β1 are found to be overexpressed in PA. In this study, integrin αvβ6/α5β1-bitargeted probes 99mTc-HYNIC-isoDGR (99mTc-isoDGR) and 99mTc-HYNIC-PEG4-PisoDGR2 (99mTc-3PisoDGR2) were prepared and evaluated in the BxPC-3 human pancreatic tumor model. Both subcutaneous and in situ BxPC-3 tumors could be clearly visualized by 99mTc-isoDGR nanoScan SPECT/CT imaging with a high ratio of tumor to background. The blocking study with excess nonradioactive peptide showed a significantly reduced tumor uptake, which confirmed the specificity of 99mTc-isoDGR. Biodistribution results confirmed the imaging results. The dimer tracer 99mTc-3PisoDGR2 significantly enhanced tumor uptake compared with 99mTc-isoDGR, and the spontaneous PA lesion in the mouse model could be clearly visualized by 99mTc-3PisoDGR2. The primary clinical study also verified the ability of 99mTc-3PisoDGR2 for detection of PA. Therefore, SPECT/CT imaging using the integrin αvβ6/α5β1-bitargeted 99mTc-3PisoDGR2 provided a potential approach for the noninvasive detection of PA.

Two-photon virtual structured illumination microscopy

One-photon structured illumination microscopy (SIM) is a powerful tool in the field of life science. To improve the resolution and imaging depth of fluorescence microscopy, we propose a novel super-resolution microscopy called two-photon virtual SIM (2p-vSIM), and establish an imaging theory model for it. To verify the resolving ability of 2p-vSIM, we carry out the simulation experiments on the Lena image and 100 nm fluorescent beads. The results show that the imaging resolution is increased by a factor of 1.95 compared with conventional two-photon imaging technology. Our 2p-vSIM has the advantages of optical sectioning and large imaging depth of two-photon microscopy as well as the super-resolution ability of virtual SIM, and enables super-resolution imaging of thick biological samples with high scattering and even dynamic super-resolution imaging of live cells.

Pseudo color night vision correlated imaging without an infrared focal plane array.

Night vision is the ability to see in low-light conditions. However, conventional night vision imaging technology is limited by the requisite high-performance infrared focal plane array. In this article, we propose a novel scheme of color night vision imaging without the use of an infrared focal plane array. In the experimental device, the two-wavelength infrared laser beam reflected by the target is modulated by a spatial light modulator, and the output light is detected by a photomultiplier tube. Two infrared night vision images are reconstructed by measuring the second-order intensity correlation function between two light fields. Thus, the processing mode of optical electric detection in conventional night vision imaging is transformed into the processing mode of light field control. Furthermore, two gray images with different spectra are processed to form a color night vision image. We show that a high-quality color night vision image can be obtained by this method.

Ternary alloyed HgCdTe nanocrystals for short-wave and mid-wave infrared region optoelectronic applications

Semiconductor quantum dots (QDs) are emerging as the forefront alternative for the conventional imaging technology, particularly in infrared region from near infrared (0.75–1.4 μm) to long-wave infrared (8–14 μm) region. A handful of materials are explored for mid infrared imaging QDs and they are all invariably binary semiconductor compounds. Ternary alloyed quantum dots in many previous cases have shown properties that are unique and better than parent binary compounds. In this work, we have synthesized ternary alloyed HgCdTe quantum dots and studied their photophysical properties. Previously studied ternary alloyed HgCdTe CQDs absorb and emit in regions limited upto near-infrared region. We have tuned the excitonic absorption of HgCdTe QDs in the range of 2.2–5 μm, where addition of cadmium clearly showed blueshift in excitonic peak as compared to that of HgTe QDs. Structural properties are studied by TEM, XRD & XPS techniques. Electrical behaviour is studied by measuring I-V, I-V-T curves. Photodetectors are fabricated in photoconductive geometry showing promising photo-response under visible (532 nm) and NIR (810 nm, 1550 nm) excitation. Responsivity of the devices is in the order of 1 mA W−1 at 1 V bias and show good linearity over irradiance range of 0.025 and 2.5 W cm−2. These results pave the way for development of next generation cost-effective short-wave and mid-wave infrared region optoelectronic devices based on narrow bandgap HgCdTe nanocrystals.

Three-dimensional angle-domain double-square-root migration in VTI media for the large-scale wide-azimuth seismic data

With the development of oil and gas exploration, the conventional seismic migration imaging technology based on the isotropic assumption no longer meets our current requirements for high-resolution images. Migration in anisotropic media has become an essential requirement for oil and gas exploration. Marine seismic exploration has gradually entered the wide-azimuth and high-density seismic data acquisition stage. However, even for current large high-performance computer clusters, it is still very difficult to implement pre-stack depth migration based on shot gathers. Thus, we present a double-square-root (DSR) equation based on three-dimensional (3D) pre-stack depth migration in midpoint-offset domain for a wide-azimuth dataset in transversely isotropic media with a vertical symmetry axis (VTI media). Considering VTI media, the DSR migration requires extensive memory and computation; we adopted the phase-shift plus interpolation approach to improve the computational efficiency. Then, we extract the angle-domain common-image gathers (ADCIGs) during DSR migration. For real large-scale seismic data, we designed an effective parallel implementation of 3D DSR migration with ADCIGs outputs. Finally, we applied the proposed angle-domain VTI DSR migration on wide-azimuth SEG/EAGE salt dome-based data and real data from the China South Sea. Numerical and practical data illustrate the effectiveness of the proposed method.

Analysis and external validation of a nomogram to predict peritoneal dissemination in gastric cancer.

ObjectivePeritoneal dissemination is difficult to diagnose by conventional imaging technologies. We aimed to construct a nomogram to predict peritoneal dissemination in gastric cancer (GC) patients.MethodsWe retrospectively analyzed 1,112 GC patients in Sun Yat-sen University Cancer Center between 2001 and 2010 as the development set and 474 patients from The Sixth Affiliated Hospital, Sun Yat-sen University between 2010 and 2016 as the validation set. The clinicopathological variables associated with gastric cancer with peritoneal dissemination (GCPD) were analyzed. We used logistic regression analysis to identify independent risk factors for peritoneal dissemination. Then, we constructed a nomogram for the prediction of GCPD and defined its predictive value with a receiver operating characteristic (ROC) curve. External validation was performed to validate the applicability of the nomogram.ResultsIn total, 250 patients were histologically identified as having peritoneal dissemination. Logistic regression analysis demonstrated that age, sex, tumor location, tumor size, signet-ring cell carcinoma (SRCC), T stage, N stage and Borrmann classification IV (Borrmann IV) were independent risk factors for peritoneal dissemination. We constructed a nomogram consisting of these eight factors to predict GCPD and found an optimistic predictive capability, with a C-index of 0.791, an area under the curve (AUC) of 0.791, and a 95% confidence interval (95% CI) of 0.762−0.820. The results found in the external validation set were also promising.ConclusionsWe constructed a highly sensitive nomogram that can assist clinicians in the early diagnosis of GCPD and serve as a reference for optimizing clinical management strategies.

Detection of proteoglycan loss from articular cartilage using Brillouin microscopy, with applications to osteoarthritis.

The degeneration of articular cartilage (AC) occurs in osteoarthritis (OA), which is a leading cause of pain and disability in middle-aged and older people. The early disease-related changes in cartilage extra-cellular matrix (ECM) start with depletion of proteoglycan (PG), leading to an increase in tissue hydration and permeability. These early compositional changes are small (<10%) and hence difficult to register with conventional non-invasive imaging technologies (magnetic resonance and ultrasound imaging). Here we apply Brillouin microscopy for detecting changes in the mechanical properties and composition of porcine AC. OA-like degradation is mimicked by enzymatic tissue digestion, and we compare Brillouin microscopy measurements against histological staining of PG depletion over varying digestion times and enzyme concentrations. The non-destructive nature of Brillouin imaging technology opens new avenues for creating minimally invasive arthroscopic devices for OA diagnostics and therapeutic monitoring.