Enhancement Imaging Research Articles

NCOG-13. OUTCOMES OF CNS WHO GRADE 2 OLIGODENDROGLIOMA IN ADULT PATIENTS ; IMPACT OF ADJUVANT TREATMENT ON OVERALL RESULTS

Abstract OBJECTIVE Patients with oligodendroglioma (ODG), isocitrate dehydrogenase (IDH)-mutant, 1p19q codeleted, CNS WHO grade 2 have a median overall survival of longer than 10 years. Patients with ODG who are high-risk by RTOG criteria are offered radiation in combination with procarbazine, lomustine, and vincristine (PCV). The study aims to analyze the patient’s outcomes and assess the efficacy of postoperative treatment. METHODS A total of 138 adult patients who underwent resection for newly diagnosed grade 2 ODG between 1994 and 2021 were enrolled. Sixty-three (45.7%) were observed after gross total resection (GTR) or near total resection (NTR), 5 (0.4%) received adjuvant treatment after GTR or NTR, 37 (26.8%) were observed after subtotal resection (STR) or biopsy, and 33 (24.0%) received adjuvant treatment after STR or biopsy. The study analyzed progression-free survival (PFS), overall survival (OS), and risk variables. RESULTS Out of the 138 patients, 38 (27%) patients received adjuvant treatment, with 30 of them (78.9%) underwent radiotherapy only, 6 (15.8%) underwent radiochemotherapy, and 2 (5.3%) received chemotherapy alone. The median PFS was 6.8 years. Multivariate analysis revealed STR or biopsy (p=0.04), initial MR imaging enhancement (p=0.002), and postoperative observation(p=0.006) were associated with poorer PFS outcomes. The 5-year overall survival rate was 95.5% and the 10-year overall survival was 76.1%. Poor OS prognosis was associated with STR or biopsy (p=0.03), preoperative seizure (p=0.002), and initial MR imaging enhancement (p< 0.001). CONCLUSIONS : GTR and NTR is essential for achieving prolonged PFS and OS in ODG patients. Postoperative treatment is associated with favorable PFS outcomes but does not significantly affect OS. For an accurate diagnosis and appropriate treatment, the utmost care should be taken to avoid underestimating the results of the biopsy.

Role and prognostic relevance of cardiac magnetic resonance imaging in the assessment of left ventricular non-compaction cardiomyopathy: review and meta-analysis

Abstract Background Left ventricular non-compaction (LVNC) is a heterogeneous myocardial disorder characterized by prominent myocardial trabeculation with deep inter-trabecular recesses, thin epicardial layer of compacted myocardium and extensive non-compacted inner muscular layer. Although several diagnostic criteria have been proposed, prediction of major adverse cardiovascular and cerebrovascular events (MACCE) still remains challenging in patients with LVNC. Objectives Objectives of our study were to perform systemic review and meta-analysis of published literature evaluating role and prognostic significance of the late gadolinium enhancement (LGE) in cardiac magnetic resonance imaging (CMR) study, its association with MACCE and characteristics of CMR derived feature-tracking (FT) strain analysis in patients with LVNC. Methods The objectives, literature search strategies, inclusion and exclusion criteria, outcome measurements, and methods of statistical analysis were analyzed according to an established protocol of the cochrane collaboration steps and meta-analysis of observational studies in epidemiology recommendations (MOOSE). Case control studies with evaluated prevalence of LGE in LVNC cardiomyopathy patients with and without MACCE and studies comparing FT strain: left ventricular global longitudinal (LV GLS), global circumferential (GCS) and global radial (GRS) strain between patients with and without LVNC has been included in the analysis. Results A total of 936 papers were collected according to our searching criteria, of those 9 studies including 416 LVNC cardiomyopathy patients with MACCE and 673 LVNC patients without MACCE and with evaluated LGE (including three studies with LVNC and heart failure), also 6 studies including 267 LVNC patients and 283 controls with evaluated FT LV GLS, GCS and GRS (measured in four studies) were selected. LGE was more frequently observed in LVNC patients with MACCE as compared to those without MACCE [RR (95 %CI) 2.52 (1.63 to 3.88); p<0.00001] (Fig.1). FT LV GLS was significantly more affected in LVNC patients compared to controls (St. mean difference (95 %CI): 1.40 (0.69 to 2.11); p<0.00001], as well as GCS and GRS (Fig. 2). Conclusions In patients with LVNC evaluated with CMR, LGE shows association with adverse cardiovascular and cerebrovascular events. CMR deformation indices: FT LV GLS, GCS, and GRS are significantly affected in patients with LVNC as compared to controls. This new CMR technique may be a complementary tool for timely detection and differentiation of LVNC cardiomyopathy and to avoid life threatening adverse events.Figure 1Figure 2

Abstract 17765: Stress Myocardial Blood Flow is Abnormal During Acute Takotsubo Syndrome

Introduction: Coronary microvascular dysfunction (CMD) is a proposed mechanism for takotsubo syndrome (TS). Therefore, we performed cardiac magnetic resonance imaging (CMR) with quantitative stress/rest perfusion and T2 mapping during acute TS and at 6-month post recovery. AIM: Quantitate stress/rest myocardial blood flow (MBF) in acute/recovery TS and compare basal with apical MBF. Methods: TS diagnosed by internationally accepted criteria. Each patient underwent acute and 6-month recovery CMR with automated in-line quantification of global/regional MBF, cine imaging, T2-mapping, and late gadolinium enhancement (LGE) imaging. Normal rest and stress MBF are 0.8-1.0 and > 2.0 ml/min/g, normal myocardial perfusion reserve (MPR) is > 2.4. Results: Acute and recovery studies were performed on 7 patients, all women, average age 63 + 8.5 years. CMR was performed within 72 hours of TS diagnosis. Initial versus (vs) follow-up EF: 40.3% vs 67.1%, left ventricular (LV) mass: 108.7 grams vs 86.3 grams. Acute studies demonstrated hypokinesis in the mid-apical segments with corresponding myocardial edema, LGE was absent in all patients. Myocardial edema and wall motion abnormality normalized at recovery. During acute TS, rest and stress MBF were 1.14 and 2.58 ml/min/g (base) vs 0.96 and 1.73 ml/min/g (apex). While at recovery, rest-stress MBF were 1.14 and 3.12 ml/min/g at base versus 1.09 and 2.76 ml/min/g at apex (Figure). MPR improved from acute to recovery: 2.14 vs 2.74 (global), 2.25 vs 2.84 (base), and 1.85 vs 2.64 (apex); p = 0.126; 0.035; 0.012 respectively (Figure). Conclusion points: Resting MBF is normal during acute TS in both basal and apical LV segments despite typical apical ballooning consistent with stunned myocardium. MPR is more abnormal in apical than base segments during acute TS, returning to normal at recovery. Myocardial edema might contribute to apical CMD during acute TS.

Abstract 17846: Successful Treatment of Recurrent Pericarditis With Rilonacept in the Setting Of ATRA/ATO Use in Acute Promyelocytic Leukemia

Case Presentation: A 40-year-old female was admitted for a 4-day history of recurrent left-sided pleuritic chest pain. Physical examination was pertinent for tachycardia and presence of a pericardial friction rub. Past medical history included recently diagnosed Acute Promyelocytic Leukemia undergoing active chemotherapy. Complete blood count showed leukopenia. Brain natriuretic peptide was slightly elevated at 241 pg/mL. Electrocardiogram demonstrated sinus tachycardia with diffuse ST-segment elevation and PR-segment depression (Figure 1. A). Echocardiogram showed normal biventricular function with a small posterior and lateral pericardial effusion and small pericardial effusion adjacent to the right ventricle (Figure 1. B). Cardiac magnetic resonance (CMR) imaging showed a moderate circumferential pericardial effusion and increased pericardial signal on T2 STIR imaging and late gadolinium enhancement (LGE) (Figure 1. C, D). Given the constellation of symptoms and findings, the patient was diagnosed with acute pericarditis secondary to differentiation syndrome (DS) suspected to be due to her underlying malignancy and anti-cancer treatments. She was started on aspirin and colchicine. Steroids and rilonacept were later added for incomplete treatment response. On follow-up, she was doing well. Repeat CMR demonstrated mild to moderate pericardial delayed enhancement with no edema and no pericardial effusion (Figure 1. E,F). Discussion: The presentation of DS can vary, and consensus diagnostic criteria are lacking. Cases of myopericarditis with concurrent pericardial effusions have been reported in the setting of patients undergoing chemotherapeutic treatment with differentiating agents. Management is complicated and requires multi-disciplinary care. Our case illustrates that rilonacept may be considered as an alternative to corticosteroids in the treatment of recurrent pericarditis in a patient with a hematologic malignancy.

Facile Synthesis of Polymer Capped NiO Nanoparticles, Characterization, Photocatalytic and their Antibacterial Activities

In the field of nanotechnology, the creation of efficient and efficient procedures for the synthesis of nanoparticles was important. The field of nanotechnology focused on the creation and application of devices and structures with organisational characteristics between the size of a single molecule and around 100 nm, where unique qualities emerge in contrast to bulk materials. The biological applications of nickel oxide include the enhancement of magnetic resonance imaging, the storage of magnetic data and the purification of biological samples using ferrofluids for catalysis, drug delivery, sensors and pigments. In this study, a new inorganic (NIO) nanoparticle's potential photocatalytic and antibacterial activities were examined. A straightforward chemical process was used to effectively produce nickel oxide nanoparticles. Polyvinyl alcohol serves as a polymer capping agent. The structure morphology and crystalline phase of NiO nanocrystals were investigated by XRD, SEM and TEM. The optical study was investigated by FT-IR spectroscopy. The anti-microbial activity of nanoparticles was determined by Gram-positive and Gram-negative bacteria.

Non-invasive monitoring of neoadjuvant radiation therapy response in soft tissue sarcomas by multiparametric MRI and quantification of circulating tumor DNA-A study protocol.

Wide resection remains the cornerstone of localized soft-tissue sarcomas (STS) treatment. Neoadjuvant radiation therapy (NRT) may decrease the risk of local recurrences; however, its effectiveness for different histological STS subtypes has not been systematically investigated. The proposed prospective study evaluates the NRT response in STS using liquid biopsies and the correlation of multiparametric magnetic resonance imaging (mpMRI) with histopathology and immunohistochemistry. Patients with localized high-grade STS, who qualify for NRT, are included in this study. Quantification of circulating tumor DNA (ctDNA) in patient blood samples is performed by targeted next-generation sequencing. Soft-tissue sarcoma subtype-specific panel sequencing in combination with patient-specific exome sequencing allows the detection of individual structural variants and point mutations. Circulating free DNA is isolated from peritherapeutically collected patient plasma samples and ctDNA quantified therein. Identification of breakpoints is carried out using FACTERA. Bioinformatic analysis is performed using samtools, picard, fgbio, and the MIRACUM Pipeline. Combination of conventional MRI sequences with diffusion-weighted imaging, intravoxel-incoherent motion, and dynamic contrast enhancement. Multiparametric MRI is performed before, during, and after NRT. We aim to correlate mpMRI data with the resected specimen's macroscopical, histological, and immunohistochemical findings. Preliminary data support the notion that quantification of ctDNA in combination with tumor mass characterization through co-registration of mpMRI and histopathology can predict NRT response of STS. The methods presented in this prospective study are necessary to assess therapy response in heterogeneous tumors and lay the foundation of future patient- and tumor-specific therapy concepts. These methods can be applied to various tumor entities. Thus, the participation and support of a wider group of oncologic surgeons are needed to validate these findings on a larger patient cohort.

Super-Resolution Imaging Enhancement through a 2D Scanning Galvanometer: Algorithm Formulation and Application in Aerial Optoelectronic Systems

As the fields of aviation and aerospace optics continue to evolve, there is an increasing demand for enhanced detection capabilities in equipment. Nonetheless, in applications where both optical and mechanical constraints are stringent, the continuous expansion of optical aperture and focal length is impractical. Given the existing technological landscape, employing super-resolution algorithms to enhance the imaging capability of optical systems is both practical and highly relevant. This study capitalizes on using a 2D scanning galvanometer in optical systems to acquire micro-displacement information. Initially, an imaging model for optical systems equipped with a 2D scanning galvanometer was established, and the displacement vectors for both forward and sweep image motions were defined. On this foundation, we incorporated micro-displacement information that can induce high-frequency aliasing. Subsequently, the motion paths of the galvanometer were planned and modeled. To align image sequences with micro-displacement correlations, the Lucas–Kanade (L-K) optical flow method was employed with multi-layer pyramid iteration. Then, super-resolution reconstruction was performed using kernel regression techniques. Ultimately, we tested the algorithm on an aeronautical optoelectronic pod to evaluate its impact on optical resolution and imaging quality. Compared with the original images, the 16-frame image demonstrated a 39% improvement in optical resolution under laboratory conditions. Moreover, the algorithm exhibited satisfactory performance under both nighttime and daytime conditions, as well as during aerial tests.

Cranial nerve VII on gadolinium contrast-enhanced magnetic resonance imaging in the case of Bell’s palsy

Bell’s palsy is a rapid unilateral peripheral paralysis of cranial nerve VII whose etiology is varied, most commonly associated with an acute infectious or inflammatory demyelinating process. Nerve injury can result in edema because of increased permeability of vascular structures, which can sometimes be seen as a locus of enhancement of magnetic resonance imaging (MRI). Bell’s palsy is typically considered a clinical diagnosis and the specificity and sensitivity of imaging have been poorly studied. Herein is describe a case of a 73-year-old male who presented to the emergency department with left-sided facial droop and no other focal neurological abnormalities. With a history of a Janus kinase 2 (JAK2) mutation and the new initial facial drooping, acute cerebrovascular insult was high on the differential. Initial labs and computerized tomography (CT) head were inconclusive, but MRI showed pronounced enhancement of the left distal internal carotid artery (ICA) with contiguous enhancement of the labyrinthine, geniculate, and tympanic segments of the left facial nerve. Diagnosing Bell’s palsy can be a challenge as there are numerous postulated etiologies stemming from trauma, infection, and neoplasm; with infection (particularly viral) postulated to be the most likely source. Though MRI is currently not validated as a tool in expediting Bell’s palsy diagnosis, findings such as the enhancement seen here provide some insight into the benefit of MRI as a diagnostic modality in some cases. This case is unique both for the diagnostic dilemma between stroke and Bell’s palsy and the potential for MRI imaging to help guide clinical decision-making into treatment.

All-in-focus large-FOV GRIN lens imaging by multi-focus image fusion

Gradient refractive index (GRIN) lenses are useful for miniaturized and in-vivo imaging. However, the intrinsic field-dependent aberrations of these lenses can deteriorate imaging resolution and limit the effective field of view. To address these aberrations, adaptive optics (AO) has been applied which inevitably requires the incorporation of additional hardware. Here we focus on field curvature aberration and propose a computational correction scheme which fuses a z-stack of images into a single in-focus image over the entire field of view (FOV), with no AO required. We validate our method by all-in-focus wide-field imaging of a printed letter sample and fluorescently labeled mouse brain slices. The method can also provide what we believe to be a new and valuable option for imaging enhancement in the scanning-modality use of GRIN lens microscopy.

Using the non-distortion IVIM to reduce the need for contrast agents in nasopharyngeal MRI

BackgroundPatients with nasopharyngeal carcinoma (NPC) who undergo longitudinal follow-up contrast-enhanced MRI are at risk of developing gadolinium deposition in their neural tissue, which may potentially harm them. Therefore, for these patients, a non-contrast-enhanced method is potentially beneficial as an alternative approach to predict enhancement in T1-weighted imaging (CE-T1WI). The traditional intravoxel incoherent motion (IVIM) is one of the non-contrast-enhanced methods; however, the severe distortion and signal loss limit its application in patients with NPC. The present study aimed to investigate whether non-distortion IVIM could reduce the need of CE-T1WI in the follow-up of patients with NPC. MethodsThe patients with NPC underwent Turbo Spin-echo MVXD diffusion-weighted imaging-based IVIM (non-distortion IVIM) from November 2021 to May 2022. Firstly, thirty patients with NPC were underwent both non-distortion IVIM and traditional IVIM. The distortion rate (DR) of the non-distortion IVIM was compared with the traditional IVIM. Then, twenty-one NPC patients with tumors (areas >50mm2) were included and correlation coefficient analysis was used to assess the relationship between their non-distortion IVIM and CE-T1WI. Linear regression analysis was performed to determine whether non-distortion IVIM predictors could predict CE-T1WI. ResultsThe correlation was observed between the parameter f of the non-distortion IVIM and the enhancement ratio of CE-T1WI (r = 0.543, P = 0.011). Moreover, the linear regression analysis revealed that f was an independent IVIM predictor of CE-T1WI in patients with NPC (P = 0.011). The DR of the non-distortion IVIM was significantly smaller than that of the traditional IVIM (0.12 ± 0.05 vs 0.48 ± 0.16, P < 0.001). ConclusionsIn patients with NPC, non-distortion IVIM showed potential clinical benefits to reduce the need for contrast agents, and it can independently predict the enhancement ratio.

Fluorescence Enhancement of Adamantane-Modified Dyes in Aqueous Solution via Supramolecular Interaction with Methyl-β-cyclodextrin and Their Application in Cell Imaging.

The fluorescence of functional dyes was generally quenched in aqueous solution, which hindered their application in water-bearing detections. In this work, a novel strategy based on host-guest interaction was provided for the purpose of fluorescence enhancement in aqueous solution and cell imaging. Three adamantane-modified fluorescent dyes (Coum-Ad, NP-Ad, NR-Ad) with coumarin, 1,8-naphthalimide and Nile Red as fluorophores were initially designed and prepared. The ((adamantan-1-yl)methyl)amino group, as the auxochrome of those dyes, complexed with methylated β-cyclodextrin (M-β-CD) via supramolecular interaction, and then fluorescent supramolecular nanoparticles (FSNPs) were formed by self-assembly in water. The inclusion equilibrium constant (K) could be as high as 3.94×104 M-1 . With the addition of M-β-CD, fluorescence quantum yields of these dyes were separately improved to 69.8 %, 32.9 % and 41.3 %. Inspired by the above satisfactory results, six adamantane-modified probes organelle-NPAds with organelle-targeting capability were further obtained. As the formation of hydrogen bonds between organelle-NPAd2 and M-β-CD verified by theoretical calculation, K of organelle-NPAd2 (5.13×104 M-1 ~4.53×105 M-1 ) with M-β-CD was higher than that of organelle-NPAd1 (1.15×104 M-1 ~3.66×104 M-1 ) and their fluorescence quantum yields increased to 32.8 %~83.6 % in aqueous solution. In addition, fluorescence enhancement was realized in cell imaging with the addition of M-β-CD.

Partially thrombosed giant basilar artery aneurysm with attenuated contrast enhancement of the intraluminal thrombus on vessel wall MRI after flow diversion treatment: illustrative case.

The effect of vessel wall magnetic resonance imaging (VW-MRI) enhancement in partially thrombosed aneurysms has previously indicated aneurysmal instability and a rupture risk. However, whether the contrast effect of the wall changes before or after flow diversion treatment is still under investigation. The authors report a case of a partially thrombosed basilar artery aneurysm that increased in size over a short period, worsened brainstem compression symptoms, and was treated with a flow diverter stent with good results. In this case, VW-MRI after surgery showed a reduced contrast effect on the intraluminal thrombus within the aneurysm. The aneurysm thrombosed and markedly regressed over the next 5 months, with remarkable improvement in the brainstem compression symptoms. This finding on VW-MRI may indicate an attenuation of neovascularization in the thrombus wall and be a sign of aneurysm stabilization.

MR features of primary bone lymphoma in children.

Primary lymphoma of bone is an uncommon non-Hodgkin lymphoma. Magnetic resonance imaging (MRI) features of primary lymphoma of bone in children are not well described. To identify typical MRI characteristics of pediatric primary lymphoma of bone at diagnosis and following treatment. Two pediatric radiologists retrospectively reviewed all imaging studies of 10 patients with biopsy-proven primary lymphoma of bone at presentation and after treatment. Anatomic location, number of sites, location within bone (epiphyseal, metaphyseal, diaphyseal), T1-weighted imaging margins, soft tissue mass, T2-weighted imaging appearance and enhancement pattern (homogeneous, heterogeneous, infarct-like), soft tissue edema, cortical disruption, and regional lymph nodes as seen on MRI as well as radiographic and positron emission tomography (PET) findings were recorded. Pathologic results, treatment plans, and outcomes at follow-up as detailed in the medical record were tabulated. Of 10 patients, age at diagnosis 8-17 years, median 15 years, 4 (40%) had multifocal disease. MRI revealed 20 total lesions in the 10 patients with femoral lesions most common, being present in7 (70%) ofpatients. Eight (80%) patients had at least one lesion around the knee. Eight (80%) patients had 1 or more lesions involving an epiphysis and 5 (50%) had at least 1 lesion confined to the epiphysis. Seven (70%) showed infarct-like appearance on T2-weighted imaging; 7 (88%) of the 8 patients with post-contrast imaging had infarct-like enhancement. Six (60%) had sharp T1 margins, 3 (30%) had cortical disruption, 8 (80%) had at least mild soft tissue edema, and 1 (10%) had soft tissue mass. Three (30%) had at least 1 PET-positive regional lymph node. At follow-up (range 1-108 months, median 4.3 months), all had residual osseous abnormality on MRI with 6 (60%) maintaining an infarct-like or combination of infarct-like and T2 hyperintense appearance. Our results in this series of pediatric primary lymphoma of bone identified several frequent MR imaging features. Multifocality, epiphyseal involvement (especially about the knee), infarct-like enhancement pattern, sharp T1 margins, and surrounding soft tissue edema should raise suspicion for primary lymphoma of bone. Following treatment, residual osseous abnormality is expected on MRI.

Clinical symbiosis of hybrid nanoparticles and induced magnetic field on heat and mass transfer in multiple stenosed artery with erratic thrombosis

This article scrutinizes blood circulation through an artery having magnetized hybrid nanoparticles (silver and gold) with multiple stenoses at the outer walls and erratic thrombus of different radii at the center. In the realm of biomedical innovation, magnetized hybrid nanoparticles emerge as a captivating frontier. These nanoparticles, amalgamating diverse materials, exhibit magnetic properties that engender novel prospects for targeted drug delivery, medical imaging enhancement, and therapeutic interventions. The study was carried out employing modern bio-fluid dynamics (BFD) software. In this iterative procedure, a second-order finite difference approach is used to solve the governing equations with 0.005 tolerance. The experiment is performed on a blood conduit with mild stenosis assumptions, and expressions of temperature, resistance impedance to flow, velocity, wall shear stress, and pressure gradient are generated by employing related boundary conditions. No one has ever attempted to acquire the remedial impact of an induced magnetic field and hybrid nanoparticles on the bloodstream in a tapering artery containing multiple stenoses on the outside walls and multi-thrombus at the center using 3-D bio-fluid simulation. Furthermore, the study's findings are unique, and these computational discoveries were not previously published by any researcher. The findings suggest that hybrid nanoparticles can be used as medication carriers to reduce the impact of thrombosis and stenosis-induced resistance to blood flow or coagulation-related factors.

Statins may Decrease Aneurysm wall Enhancement of Unruptured Fusiform Intracranial Aneurysms: A high-resolution 3T MRI Study.

Inflammation plays an integral role in the formation, growth, and progression to rupture of unruptured intracranial aneurysms. Aneurysm wall enhancement (AWE) in high-resolution magnetic resonance imaging (HR-MRI) has emerged as a surrogate biomarker of vessel wall inflammation and unruptured intracranial aneurysm instability. We investigated the correlation between anti-inflammatory drug use and three-dimensional AWE of fusiform intracranial aneurysms (FIAs). We retrospectively analyzed consecutive patients with FIAs in our database who underwent 3T HR-MRI at three Chinese centers. FIAs were classified as fusiform-type, dolichoectatic-type, or transitional-type. AWE was objectively defined using the aneurysm-to-pituitary stalk contrast ratio in three-dimensional space by determining the contrast ratio of the average signal intensity in the aneurysmal wall and pituitary stalk on post-contrast T1-weighted images. Data on aneurysm size, morphology, and location, as well as patient demographics and comorbidities, were collected. Univariate and multivariate logistic regression analyses were performed to determine factors independently associated with AWE of FIAs on HR-MRI. In total, 127 FIAs were included. In multivariate analysis, statin use (β = -0.236, P = 0.007) was the only independent factor significantly associated with decreased AWE. In the analysis of three FIA subtypes, the fusiform and transitional types were significantly associated with statin use (rs = -0.230, P = 0.035; and rs = -0.551, P = 0.010; respectively). It establishes an incidental correlation between the use of statins daily for ≥ 6 months and decreased AWE of FIAs. The findings also indicate that the pathophysiology may differ among the three FIA subtypes.

Graphene Quantum Dots for Multifaceted Diagnostics

Due to their unique physical and electronic properties as well as high biocompatibility and water solubility, functionalized graphene quantum dots (GQDs) have found utilization in a variety of biomedical applications. GQDs can serve as carriers for drugs and genes while tracing their delivery pathways in vitro and in vivo with their visible and near-infrared fluorescence. In addition to therapeutic applications, our recent work explores diagnostic modalities of these novel nanomaterials. GQDs synthesized bottom-up form a single glucosamine precursor, or top-down from reduced graphene oxide can serve as nanoscale temperature sensors for biological processes. They exhibit linear and reversible visible/NIR fluorescence quenching by up to 19.3 % in suspension with temperature increase form 25 to 49 ⁰C. A more pronounced trend is observed in HeLa cells with over 40% quenching in that temperature range. Our findings suggest that such deterministic response can serve as non-invasive reversible/photostable mechanism for temperature sensing in microscopic subcellular biological environments. Another diagnostic modality of GQDs involves their capability for magnetic resonance imaging. When doped with Mn2+ ions during their bottom-up synthesis, GQDs exhibit substantial r₂/r₁ relaxation parameter ratios of 11.19, showing potential as dual-mode T1 or T2 contrast agents. Their Gd3+-doped counterparts possess r₂/r₁ ratios of 1.148 with high r1 of 9.546 mM-1s-1 compared to commercial contrast agents, suggesting their utilization as T1 contrast agents. Given that doping did not affect their biocompatibility or fluorescence properties, such doped GQDs can serve as multimodal MR and fluorescence imaging agents. Metal-doped GQDs possess the capability ultrasonic contrast imaging that can be utilized for higher precision and deeper tissue diagnostic applications. They demonstrate high-contrast properties in ultrasound brightness mode by a factor of 10 surpassing undoped GQD structures. The successful imaging enhancement was observed in tissue phantom and animal tissue, suggesting that GQDs can be tracked by ultrasound imaging and used as contrast agents for the improvement of the deterministic power of this widely available imaging approach. GQD intrinsic fluorescence can itself serve as a non-invasive diagnostic sensing tool, as it can be affected by the binding of different drugs, genes and biomolecules to the GQDs. This optical sensing mechanism is used in our work for identifying trace quantities of cancer-generated genes for early personalized cancer detection. The sensor is prepared from GQDs complexed with the bait DNA sequence complementary to the target pancreatic cancer miRNA. It effectively discriminates between complementary single-stranded DNA sequences and random control genes with the sensitivity in the nanomolar range. Cancer gene detection is further verified by identifying both, the stem and the loop portions of the pancreatic cancer-generated pre-miR-132. Given the success of these different diagnostic applications, GQDs can be considered a highly perspective theragnostic tool for a variety of disease targets.

Enhanced resolution of edge enhancement in three-dimensional vortex imaging based on a modified Michelson interferometer

Edge enhancement is emerging as an essential technique for object recognition in recent years. The edge detection of three-dimensional (3D) imaging has been successfully demonstrated in Fresnel incoherent correlation holograph (FINCH) system; however, with a relatively low resolution which needs to be further improved to meet practical requirements. In this work, a modified Michelson interferometer system using a spatial light modulator (SLM) is proposed, which realizes 3D vortex imaging with high resolution and low background noise. Compared with the spiral phase modulated polarization multiplexing FINCH system, the resolution of this system has apparently improved from 50.80 lp mm−1 to 57.02 lp mm−1. The improvement is assumed to be ascribed to the inherently high luminous flux utilization configuration of the Michelson interferometer and the precision phase shifts. More importantly, the proposed system exhibits prominently improved performance of edge enhancement for different objects, including the standard resolution target and label-free biological living cells. The experimental results of the small watch parts also demonstrate its ability in 3D vortex imaging with edge detection. These results provide a promising strategy for high-quality 3D vortex imaging and edge enhancement, and might pave the way for future applications in the fields such as edge detection and pattern recognition.

Augmented and Virtual Reality for Preoperative Trauma Planning, Focusing on Orbital Reconstructions: A Systematic Review.

This systematic review summarizes recent literature on the use of extended reality, including augmented reality (AR), mixed reality (MR), and virtual reality (VR), in preoperative planning for orbital fractures. A systematic search was conducted in PubMed, Embase, Web of Science and Cochrane on 6 April 2023. The included studies compared extended reality with conventional planning techniques, focusing on computer-aided surgical simulation based on Computed Tomography data, patient-specific implants (PSIs), fracture reconstruction of the orbital complex, and the use of extended reality. Outcomes analyzed were technical accuracy, planning time, operative time, complications, total cost, and educational benefits. A total of 6381 articles were identified. Four articles discussed the educational use of VR, while one clinical prospective study examined AR for assisting orbital fracture management. AR was demonstrated to ameliorate the accuracy and precision of the incision and enable the better identification of deep anatomical tissues in real time. Consequently, intraoperative imaging enhancement helps to guide the orientation of the orbital reconstruction plate and better visualize the precise positioning and fixation of the PSI of the fractured orbital walls. However, the technical accuracy of 2-3 mm should be considered. VR-based educational tools provided better visualization and understanding of craniofacial trauma compared to conventional 2- or 3-dimensional images.

Magnetic resonance detection of advanced atrial cardiomyopathy increases the risk for atypical atrial flutter occurrence following atrial fibrillation ablation.

Recurrence of arrhythmia after catheter ablation of atrial fibrillation (AF) in the form of atypical atrial flutter (AFL) is common among a significant number of patients and often requires redo ablation with limited success rates. Identifying patients at high risk of AFL after AF ablation could aid in patient selection and personalized ablation approach. The study aims to assess the relationship between pre-existing atrial cardiomyopathy and the occurrence of AFL following AF ablation. We analysed a cohort of 1007 consecutive AF patients who underwent catheter ablation and were included in a prospective registry. Patients who did not have baseline cardiac magnetic resonance imaging and late gadolinium enhancement (LGE-CMR) or did not experience any recurrences were excluded. A total of 166 patients were included gathering 56 patients who underwent re-ablation due to AFL recurrences and 110 patients who underwent re-ablation due to AF recurrences (P = 0.11). A multiparametric assessment of atrial cardiomyopathy was based on basal LGE-CMR, including left atrial (LA) volume, LA sphericity, and global and segmental LA fibrosis using semiautomated post-processing software. Out of the initial cohort of 1007 patients, AFL and AF occurred in 56 and 110 patients, respectively. An age higher than 65 [odds ratio (OR) = 5.6, 95% confidence interval (CI): 2.2-14.4], the number of previous ablations (OR = 3.0, 95% CI: 1.2-7.8), and the management of ablation lines in the index procedure (OR = 2.5, 95% CI: 1.0-6.3) were independently associated with AFL occurrence. Furthermore, several characteristics assessed by LGE-CMR were identified as independent predictors of AFL recurrence after the index ablation for AF, such as enhanced LA sphericity (OR = 1.3, 95% CI: 1.1-1.6), LA global fibrosis (OR = 1.03, 95% CI: 1.01-1.07), and increased fibrosis in the lateral wall (OR = 1.03, 95% CI: 1.01-1.04). Advanced atrial cardiomyopathy assessed by LGE-CMR, such as increased LA sphericity, global LA fibrosis, and fibrosis in the lateral wall, is independently associated with arrhythmia recurrence in the form of AFL following AF ablation.

Papel de la ecografía con contraste en la evaluación de lesiones focales esplénicas

The purpose of this article is to evaluate the role of contrast-enhanced ultrasound in the characterization of non-traumatic focal splenic lesions.Focal splenic lesions are less common than in other abdominal organs like the liver. Conventional ultrasound and Doppler ultrasound have a limited role in the characterization of splenic lesions, resulting in many of them unspecified.Contrast ultrasound is an accessible, cheap, and safe technique which can help in the immediate characterization of lesions incidentally detected in the ultrasound examination, being a good alternative to others imaging techniques.We review in detail the technique and the main indications. We also analyze imaging findings and enhancement pattern by using representative case of the main splenic lesions for both benign (epithelial cyst, cystic lymphangioma, hemangioma, hamartoma, infarction, sclerosing angiomatous nodular transformation, abscesses, sarcoidosis), and malignant (lymphoma, metastasis) and its pathological correlation in some cases.