Imaging Studies Research Articles

Analytical Study of Medical PET Images by DWT and PCA

Analytical Study of Medical PET Images by DWT and PCA

Do some levator avulsions improve over time?

To determine whether the sonographic appearance of levator avulsion after vaginal childbirth can improve significantly over the first few years postpartum. Retrospective study of women seen in the context of two prospective perinatal imaging studies. All subjects had undergone an interview, clinical examination and 4D translabial ultrasound (TLUS) on average 4.3 months and 3.1 years post-partum. Volume data sets were analysed at a later date blinded against all other data. The number of abnormal slices at both time points was compared using Mann- Whitney U Test. Patients in whom findings had changed over time were reviewed separately in parallel in order to reduce the impact of differences in slice location and imaging settings. The symmetry test was used to analyse changes between the two postnatal visits. Of 1148 women originally recruited, 315 had had at least two postnatal visits. 42 were excluded, leaving 273 women for analysis.They were first seen on average 4.3 (2.6-9.8) months after childbirth and the last time 3.1 (1.4-8) years postpartum. Cohen's kappa for the two assessments was 0.89, with agreement in 97% (264/273) of cases. At the first visit, complete avulsion was diagnosed in 20, partial avulsion in 32, and no avulsion in 221. While seven partial avulsions appeared sonographically normal at the second visit, there were no statistically significant changes in avulsion category between visits (P=0.4). Tomographic pelvic floor imaging obtained 2.5-10 months after childbirth may be used as a proxy for long- term outcomes. Findings at a mean of 3.1 years showed 97% agreement with imaging obtained at an average of 4.3 months. There was a non-significant reduction in abnormal slices affecting at most 3/12 slices. This may be explained by compensatory hypertrophy of remaining intact muscle. Sonographic normalisation of complete avulsion was not observed. This article is protected by copyright. All rights reserved.

Associations of cumulative voriconazole dose, treatment duration, and alkaline phosphatase with voriconazole-induced periostitis.

To investigate the associations of cumulative voriconazole dose, treatment duration, and alkaline phosphatase with voriconazole-induced periostitis. One hundred and thirty-one patients with voriconazole use were identified using a clinical informatics tool. Health record data including age, sex, immune status, alkaline phosphatase, voriconazole levels, voriconazole dose, frequency, and treatment duration were collected. Imaging studies during the duration of treatment were reviewed by two radiology trainees and imaging features of voriconazole-induced periostitis were confirmed by a board-certified musculoskeletal radiologist. The length, location in the body, location in the bone, type, and morphology of periostitis lesions were recorded. Incident voriconazole-induced periostitis was defined as new periostitis on imaging after 28days or more of voriconazole treatment in the absence of an alternative diagnosis. Univariate Firth's logistic regression models were performed using cumulative voriconazole dose, treatment duration, and average ALP as predictors and incident VIP as the outcome. There were nine patients with voriconazole-induced periostitis and 122 patients without voriconazole-induced periostitis. The most common lesion location in the body was the ribs (37%) and morphology was solid (44%). A 31.5-g increase in cumulative voriconazole dose was associated with 8% higher odds of incident periostitis. Increased treatment duration (63days) and higher average alkaline phosphatase (50IU/L) were associated with 7% higher odds of periostitis and 34% higher odds of periostitis, respectively. Increased cumulative voriconazole dose, treatment duration, and average alkaline phosphatase were associated with higher odds of voriconazole-induced periostitis.

Temporal trends in clinical features of patients with primary aldosteronism over 20 years.

Primary aldosteronism (PA) accounts for approximately 5-10% of hypertension cases. Over the past 20 years, the reported incidence of PA has increased due to widespread screening for secondary hypertension and imaging studies. We aimed to evaluate the temporal trends in the clinical characteristics and subtypes of PA. A total of 1064 patients with PA in two tertiary hospitals between 2000 and 2021 were categorized into three groups according to the year of diagnosis: 2000-2009, 2010-2015, and 2016-2021. The clinical characteristics of the patients over the three time periods were compared using a trend analysis. The age at diagnosis and sex of patients with PA did not change over 20 years. The proportion of patients with bilateral hyperaldosteronism (BHA) increased (11%, 25%, and 40%, P for trend <0.001). The proportion of hypokalemia (87%, 61%, and 40%) and plasma aldosterone concentration (36.0, 30.8, and 26.6 ng/dL) decreased (all P for trend <0.001). There was a trend toward an increased proportion of incidentally detected patients compared to clinically symptomatic patients (36%, 55%, and 61%, P for trend <0.001). The concordance rate of imaging and adrenal venous sampling results decreased (91%, 70%, and 57% P for trend <0.001). However, the proportion of patients with resistant hypertension and comorbidities did not differ. In conclusion, among patients with PA, patients with BHA and incidental detection have increased over 20 years, and more patients are likely to present with milder clinical symptoms and biochemical profiles.

A nitroreductase-responsive fluorescence turn-on photosensitizer for lysosomes imaging and photodynamic therapy.

Nitroreductase (NTR) is a frequently used biomarker for the assessment of hypoxia level in tumors. As one of the main sources of enzymes, the dysfunction of lysosomes typically leads to various diseases. In this study, an NTR-triggered lysosome-targeting probe, M-TPE-P, was designed based on a tetraphenylethylene core. DFT calculation indicated that the probe possessed a narrow singlet-triplet energy gap (ΔEST), rendering it an efficient photosensitizer. The docking affinity of M-TPE-P to NTR revealed a strong structural match between them. Photophysical properties demonstrated that the probe exhibited high selectivity and sensitivity in a broad pH rang for detecting NTR with kcat/Km as 2.18×104M-1 s-1. The detection limit was determined to be 53.6ng/mL in 80% PBS/DMSO solution. Cell imaging studies showed the probe could trace intracellular NTR behavior with green fluorescence. The colocalization analysis indicated its excellent lysosome-targeting specificity. In addition, the probe exhibited effective ROS generation ability and significant PDT effect after NIR irradiation, positioning it as a promising photosensitizer for cancer treatment.

Static and temporal dynamic in functional connectivity of large-scale brain networks during acute stress regulate stress resilience differently: the promotion role of trait resilience.

Stress resilience has been largely regarded as a process in which individuals actively cope with and recover from stress. Over the past decade, the emergence of large-scale brain networks has provided a new perspective for the study of the neural mechanisms of stress. However, the role of inter-network functional-connectivity (FC) and its temporal fluctuations in stress resilience is still unclear. To bridge this knowledge gap, seventy-seven participants (age, 17-22 years, 37 women) were recruited for a ScanSTRESS brain imaging study. A static perspective was initially adopted, using changes in FC that obtained from stress vs. control condition during the entire stress induction phase as a static indicator. Further, changes in FC between different stress runs were analyzed as an index of temporal dynamics. Stress resilience was gauged using salivary cortisol levels, while trait resilience was measured via behavioral-activation-system (BAS) sensitivity. Results found that, for the static index, enhanced FC between the salience-network (SN), default-mode-network (DMN) and limbic-network (LBN) during acute stress could negatively signal stress resilience. For the temporal dynamics index, FC among the dorsal-attention-network (DAN), central-executive-network (CEN) and visual-network (VN) decreased significantly during repeated stress induction. Moreover, the decline of FC positively signaled stress resilience, and this relationship only exist in people with high BAS. The current research elucidates the intricate neural underpinnings of stress resilience, offering insights into the adaptive mechanisms underlying effective stress responses.

Improved detection of magnetic interactions in proteins based on long-lived coherences.

Living systems rely on molecular building blocks with low structural symmetry. Therefore, constituent amino acids and nucleotides yield short-lived nuclear magnetic responses to electromagnetic radiation. Magnetic signals are at the basis of molecular imaging, structure determination and interaction studies. In solution state, as the molecular weight of analytes increases, coherences with long lifetimes are needed to yield advantageous through-space magnetisation transfers. Interactions between magnetic nuclei can only be detected provided the lifetimes of spin order are sufficient. In J-coupled pairs of nuclei, long-lived coherences (LLC's) connect states with different spin-permutation symmetry. Here in, weshow sustained LLC'sin protein Lysozyme, weighing 14.3 kDa, with lifetimes twice as long as those of classical magnetisation for the aliphatic protons of glycine residues. We found for the first time that, in a protein of significant molecular weight, LLC's yield substantial through-space magnetisation transfers: spin-order transfer stemming from LLC's overcame transfers from classical coherences by factors > 2. Furthermore, in agreement with theory, the permutation symmetry of LLC-based transfers allows mapping interacting atoms in the protein structure with respect to the molecular plane of glycine residues in a stereospecific manner. These findings can extend the scope of liquid-state high-resolution biomolecular spectroscopy.

Pseudolesions involving bone and soft tissue regarding orthopedic oncology.

Pseudolesions in bone and muscle are encountered mostly incidentally in routine imaging studies, especially due to the recent advancements on many different imaging modalities. These lesions can be categorized into the following categories: normal variants; congenital; iatrogenic; degenerative; and postoperative. In this review, we discuss the many different radiological characteristics of musculoskeletal pseudolesions that appear on imaging, which can prevent non-essential additional studies.

MR Imaging Features of Critical Spinal Demyelinating Lesions Associated with Progressive Motor Impairment.

Progressive MS is typically heralded by a myelopathic pattern of asymmetric progressive motor weakness. Focal individual "critical" demyelinating spinal cord lesions anatomically associated with progressive motor impairment may be a compelling explanation for this clinical presentation as described in progressive solitary sclerosis (single CNS demyelinating lesion), progressive demyelination with highly restricted MR imaging lesion burden (2-5 total CNS demyelinating lesions; progressive paucisclerotic MS), and progressive, exclusively unilateral hemi- or monoparetic MS (>5 CNS demyelinating progressive unilateral hemi- or monoparetic MS [PUHMS] lesions). Critical demyelinating lesions appear strikingly similar across these cohorts, and we describe their specific spinal cord MR imaging characteristics. We performed a retrospective, observational MR imaging study comparing spinal cord critical demyelinating lesions anatomically associated with progressive motor impairment with any additional "noncritical" (not anatomically associated with progressive motor impairment) spinal cord demyelinating lesions. All spinal cord MR images (302 cervical and 91 thoracic) were reviewed by an experienced neuroradiologist with final radiologic assessment on the most recent MR imaging. Anatomic association with clinical progressive motor impairment was confirmed independently by MS subspecialists. Ninety-one individuals (PUHMS, 37 [41%], progressive paucisclerosis 35 [38%], progressive solitary sclerosis 19 [21%]) with 91 critical and 98 noncritical spinal cord MR imaging demyelinating lesions were evaluated. MR imaging characteristics that favored critical spinal cord demyelinating lesions over noncritical lesions included moderate-to-severe, focal, lesion-associated spinal cord atrophy: 41/91 (45%) versus 0/98 (0%) (OR, 161.91; 9.43 to >999.9); lateral column axial location (OR, 10.43; 3.88-28.07); central region (OR, 3.23; 1.78-5.88); ventral column (OR, 2.98; 1.55-5.72); and larger lesion size of the axial width (OR, 2.01;1.49-2.72), transverse axial size (OR, 1.66; 1.36-2.01), or lesion area (OR, 1.14; 1.08-1.2). Multiple regression analysis revealed focal atrophy and lateral axial location as having the strongest association with critical demyelinating lesions. Focal, lesion-associated atrophy, lateral column axial location, and larger lesion size are spinal cord MR imaging characteristics of critical demyelinating lesions. The presence of critical demyelinating lesions should be sought as these features may be associated with the development of progressive motor impairment in MS.

One-Pot Synthesis of Vinylogous Cyano Aminoaryls (VinCAs) as Benzenic Fluorophores: Tailoring Diverse Emission Colors for White Light Emitting Materials and Cell Imaging.

Donor-acceptor-based organic small molecules with an electronic push-pull effect can demonstrate intramolecular charge transfer to show interesting photoluminescence properties. This is an essential criterion for designing fluorogenic probes for cell imaging studies and the development of organic light-emitting diodes. Now, to design such optical materials sometimes it is necessary to tune the band gap by controlling the energies of the highest occupied molecular orbital and lowest unoccupied molecular orbital. Typically, the band gaps could be modulated by installing unsaturated handles between electron-rich donors and electron-deficient acceptors. However, these methods are often synthetically and economically challenging due to the involvement of expensive catalysts and difficult reaction setups. In our present study, we show a straightforward, cost-effective method for obtaining a series of donor-acceptor-type Vinylogous Cyano Aminoaryls (VinCAs) with diverse emission colors. Further studies reveal that these VinCAs can serve as effective cell imaging agents, showcasing potential use in chemical biology. Additionally, these molecules could be further used to generate white light emission (WLE), showing their potential utility in advanced lighting technologies.

Understanding Anxiety in Cervical Dystonia: An Imaging Study.

Anxiety may precede motor symptoms in cervical dystonia (CD) and is associated with an earlier onset of dystonia. Our understanding of anxiety in CD is inadequate. To investigate brain networks associated with anxiety in CD. Twenty-six subjects with idiopathic CD underwent MRI Brain without contrast. Correlational tractography was derived using Diffusion MRI connectometry. Quantitative Anisotropy (QA) was used in deterministic diffusion fiber tracking. Correlational tractography was then used to correlate QA with State-Trait Anxiety Inventory (STAI) state (STAI-S) and trait (STAI-T) subscales. Connectometry analysis showed direct correlation between state anxiety and QA in tracts from amygdala to thalamus/ pulvinar bilaterally, and trait anxiety and QA in tracts from amygdala to motor cortex, sensorimotor cortex and parietal association area bilaterally (FDR ≤0.05). Our efforts to map anxiety to brain networks in CD highlight the role of the amygdala in the pathophysiology of anxiety in CD.

Simulation study of compressed ultrafast 3D imaging based on interferometry

Observing the 3D (three-dimensional) surface vibration in 100 MHz is challenging due to low speed of CCD/CMOS camera. In order to obtain the ultrafast dynamic 3D shape information, a compressed ultrafast 3D imaging framework based on interferometry is proposed in this paper. Based on this imaging framework, an reconstruction method combining plug and play-fast flexible denoising network is developed to recover high resolution interference fringe patterns and the corresponding 3D information. The simulation results show that the proposed method can observe the dynamic processes of the anti-phase vibration and the in-phase vibration of the crystal oscillator, therefore the dynamic 3D model is established. The proposed method outperforms other reconstruction methods in terms of average peak signal to noise ratio and structural similarity in recovery the ultrafast dynamic 3D surface.

Bora-diaza-indacene based fluorescent probes for simultaneous visualisation of lipid droplets and endoplasmic reticulum.

Organelle selective fluorescent probes, especially those capable of concurrent detection of specific organelles, are of benefit to the research community in delineating the interplay between various organelles and the impact of such interaction in maintaining cellular homeostasis and its disruption in the diseased state. Although very useful, such probes are synthetically challenging to design due to the stringent lipophilicity requirement posed by different organelles, and hence, the lack of such probes being reported so far. This work details the synthesis, photophysical properties, and cellular imaging studies of two bora-diaza-indacene based fluorescent probes that can specifically and simultaneously visualise lipid droplets and endoplasmic reticulum; two organelles suggested having close interactions and implicated in stress-induced cellular dysfunction and disease progression.

Hemangioma of the buccal mucosa treated with sclerotherapy: A rare case report

Hemangiomas are common benign vascular anomalies that can occur in various locations throughout the body, including the oral cavity. The lesions are generally asymptomatic and exhibit a variation in the size and colour. Here, we present a case report of a hemangioma located in the buccal mucosa of a 40-year-old female patient who presented with asymptomatic reddish purplish swellings in the buccal mucosa, which had gradually increased in size over the last 6 months. Clinical examination and imaging studies confirmed the diagnosis of a hemangioma. 1 ml of 3% of sclerosing agent (sterol; sodium tetradecyl sulphate) mixed with lignocaine HCL was injected in the periphery of the lesion, once a week for 3 weeks, and periodic follow-up evaluation revealed a marked reduction in the lesion size. This case demonstrates the feasibility and efficacy of sclerotherapy as a minimally invasive treatment option for hemangiomas of the buccal mucosa, particularly in cases where surgical excision may be technically challenging or associated with significant morbidity.

Inflammatory myofibroblastic tumor of urinary bladder in young male: A case report and literature review

The objective of this study is to present a rare case of inflammatory myofibroblastic tumor (IMT) of the urinary bladder in young male, detailing its clinical presentation, diagnostic approach, treatment strategy, and outcome. Additionally, the objective includes conducting a literature review to provide insights into the characteristics, management, and prognosis of this uncommon tumor entity.A 20-year-old male presenting with dysuria and dribbling of urine underwent diagnostic workup including imaging studies, cystoscopy. On cystoscopy there was a presence of 5x4 cm sized pedunculated mass in the urinary bladder. Partial cystectomy is done and specimen is examined for histopathology. Histopathological examination and Immunohistochemistry study of the tumor specimen was performed to confirm the diagnosis of inflammatory myofibroblastic tumor. A thorough literature review was conducted to gather relevant studies on IMT of the urinary bladder, focusing on clinical presentations, diagnostic modalities, treatment approaches, and outcomes. Diagnostic evaluation revealed a mass lesion in the urinary bladder, and histopathological examination following partial cystectomy confirmed the diagnosis of inflammatory myofibroblastic tumor. The patient underwent surgical excision of the tumor followed by adjuvant therapy. Regular follow-up examinations showed no evidence of tumor recurrence. The literature review identified a limited number of reported cases of IMT of the urinary bladder in young male, emphasizing its rarity and diverse clinical presentations. Various diagnostic modalities and treatment options, including surgery, chemotherapy, and targeted therapy, were discussed in the reviewed literature. Inflammatory myofibroblastic tumor of the urinary bladder is a rare neoplasm at younger age that can present with nonspecific symptoms, making its diagnosis challenging. However, timely recognition and appropriate management, including surgical resection and adjuvant therapy, can lead to favorable outcomes with low recurrence rates. This case report highlights the importance of considering IMT in the differential diagnosis of bladder masses in young patient and underscores the need for further research to better understand the pathogenesis and optimal treatment strategies for this rare tumor entity.

[68Ga]Ga-NODAGA-TriGalactan, a low molecular weight tracer for the non-invasive imaging of the functional liver reserve

BackgroundDetermination of the functional liver mass is important in a variety of clinical settings including liver surgery and transplantation. [99mTc]Tc-diethylenetriamine-pentaacetic acid galactosyl human serum albumin (99mTc-GSA) is a radiotracer targeting the asialoglycoprotein receptor (ASGR) and is routinely used in Japan for this purpose. Here we describe the development and evaluation of [68Ga]Ga-NODAGA-TriGalactan a low molecular weight PET-tracer targeting this structure.ResultsFor synthesis TRIS as branching unit and NODAGA as chelator for labelling with [68Ga]Ga are included. Three galactose moieties are conjugated via a click chemistry approach resulting in the desired labelling precursor.68Ga-labelling could be accomplished in high radiochemical yield and purity. [68Ga]Ga-NODAGA-TriGalactan is very hydrophilic and revealed high plasma stability and low plasma protein binding. Fluorescence imaging showed binding on ASGR-positive organoids and the IC50-value was in the nanomolar range. Most importantly, both biodistribution as well as animal imaging studies using normal mice demonstrated high liver uptake with rapid elimination from all other organs leading to even higher liver-to-background ratios as found for 99mTc-GSA.Conclusion[68Ga]Ga-NODAGA-TriGalactan shows high in vitro stability and selectively binds to the ASGR allowing imaging of the functional liver mass with high contrast. Thus, our first generation compound resulted already in an alternative to 99mTc-GSA for imaging the functional liver reserve and might allow the broader use of this imaging technique.

Retroperitoneal Müllerian Cyst Found Incidentally During Total Laparoscopic Hysterectomy: Is There a Role for MRI in Pre-Operative Evaluation?

Retroperitoneal Müllerian Cyst Found Incidentally During Total Laparoscopic Hysterectomy: Is There a Role for MRI in Pre-Operative Evaluation?

Western diet increases brain metabolism and adaptive immune responses in a mouse model of amyloidosis

Diet-induced increase in body weight is a growing health concern worldwide. Often accompanied by a low-grade metabolic inflammation that changes systemic functions, diet-induced alterations may contribute to neurodegenerative disorder progression as well. This study aims to non-invasively investigate diet-induced metabolic and inflammatory effects in the brain of an APPPS1 mouse model of Alzheimer’s disease. [18F]FDG, [18F]FTHA, and [18F]GE-180 were used for in vivo PET imaging in wild-type and APPPS1 mice. Ex vivo flow cytometry and histology in brains complemented the in vivo findings. 1H- magnetic resonance spectroscopy in the liver, plasma metabolomics and flow cytometry of the white adipose tissue were used to confirm metaflammatory condition in the periphery. We found disrupted glucose and fatty acid metabolism after Western diet consumption, with only small regional changes in glial-dependent neuroinflammation in the brains of APPPS1 mice. Further ex vivo investigations revealed cytotoxic T cell involvement in the brains of Western diet-fed mice and a disrupted plasma metabolome. 1H-magentic resonance spectroscopy and immunological results revealed diet-dependent inflammatory-like misbalance in livers and fatty tissue. Our multimodal imaging study highlights the role of the brain-liver-fat axis and the adaptive immune system in the disruption of brain homeostasis in amyloid models of Alzheimer’s disease.

Feasibility Study of Scanning Spectral Imaging Based on a Birefringence Flat Plate

Hyper-spectral imaging (HSI) systems can be divided into two main types as follows: a group of systems that includes a dedicated dispersion/filtering component whose role is to physically separate the different wavelengths and a group of systems that sample all wavelengths in parallel, so that the separation into wavelengths is performed by signal processing (interferometric method). There is a significant advantage to systems of the second type in terms of the integration time required to obtain a signal with a high signal-to-noise ratio since the signal-to-noise ratio of methods based on scanning interferometry (Windowing method) is better compared to methods based on dispersion. The current research deals with the feasibility study of a new concept for an HSI system that is based on scanning interferometry using the “push-broom” method. In this study, we investigated the viability of incorporating a simple birefringent plate into a scanning optical system. By exploiting the motion of the platform on which the system is mounted, we extracted the spectral information of the scanned region. This approach combines the benefits of scanning interferometry with the simplicity of the setup. According to the theory, a chirped cosine-shaped interferogram is obtained for each wavelength due to the nonlinear behavior of the optical path difference of light in the birefringent plate as a function of the angle. An algorithm converts the signal from a superposition of chirped cosine signals to a scaled interferogram such that Fourier transforming (FT) the interferogram retrieves the spectral information. This innovative idea can turn a simple monochrome camera into a hyperspectral camera by adding a relief lens and a birefringent plate.

Automatically targeting the dorsolateral subthalamic nucleus for functional connectivity-guided rTMS therapy

Aim: Many resting-state functional magnetic resonance imaging (rs-fMRI) studies have provided evidence that repetitive transcranial magnetic stimulation (rTMS) exerts treatment effects via functional connectivity (FC) from a superficial stimulation target to a deep effective region. The dorsolateral subthalamic nucleus (DL-STN) is an effective target in deep brain stimulation surgery for Parkinson’s disease (PD), but its targeting highly depends on well-trained neurosurgeons and is not easily used for FC-guided rTMS. We aimed to devise a method for automatically localizing the DL-STN, and further develop a one-stop plug-in of rs-fMRI FC analysis to assist future individualized FC-guided rTMS. Methods: Based on structural and iron-sensitive MRI of 78 participants, two raters defined the DL-STN coordinates with very high reliability. The averaged coordinates in the standard Montreal Neurological Institute (MNI) space were: left DL-STN, x: -11.89 ± 0.82, y: -14.51 ± 1.00, and z: -6.40 ± 1.01 and the right DL-STN, x: 12.53 ± 0.77, y: -13.97 ± 0.86, and z: -6.57 ± 0.99. As the individual distances from the averaged coordinates were less than 3 mm (within one voxel for most rs-fMRI studies) for all 78 participants, we defined the average coordinates as AutoSTN. We then developed a one-stop plug-in named Connectivity and Coordinates Converting Assistant Toolbox (CC-CAT) and performed AutoSTN FC analysis. Results: The AutoSTN seed showed significant FC with the motor cortices in all participants. Conclusion: The AutoSTN-based rs-fMRI FC could guide future rTMS on PD. The one-stop plug-in CC-CAT can be used for any FC-guided rTMS treatment.