Advanced Imaging Techniques Research Articles

Magnetic Resonance Myocardial Imaging in Patients With Implantable Cardiac Devices: Challenges, Techniques, and Clinical Applications.

Cardiovascular magnetic resonance imaging (MRI) in patients with cardiac implants, such as pacemakers and defibrillators, has gained importance in recent years with the development of modern cardiac implantable electronic devices. The increasing clinical need to perform MRI examinations in patients with cardiac implants has driven the development of new advanced MRI sequences to mitigate image artifacts associated with cardiac implants. More specifically, advances in imaging techniques, such as wideband late gadolinium enhancement imaging, wideband T1 mapping, and wideband perfusion, have been designed to improve image quality and examinations in patients with cardiac implants, enabling a comprehensive and more reliable diagnosis, which was previously unattainable in these patients. This review article explores recent developments and applications of wideband techniques in the field of cardiovascular MRI, offering insights into their transformative potential. Clinical applications of wideband cardiovascular MRI are highlighted, particularly in assessing myocardial viability, guiding ventricular tachycardia ablation, and characterizing myocardial tissue.

Novel imaging tools to study mitochondrial morphology in Caenorhabditis elegans.

Mitochondria exhibit a close interplay between their structure and function. Understanding this intricate relationship requires advanced imaging techniques that can capture the dynamic nature of mitochondria and their impact on cellular processes. However, much of the work on mitochondrial dynamics has been performed in single celled organisms or in vitro cell culture. Here, we introduce novel genetic tools for live imaging of mitochondrial morphology in the nematode Caenorhabditis elegans, addressing a pressing need for advanced techniques in studying organelle dynamics within live intact multicellular organisms. Through a comprehensive analysis, we directly compare our tools with existing methods, demonstrating their advantages for visualizing mitochondrial morphology and contrasting their impact on organismal physiology. We reveal limitations of conventional techniques, whereas showcasing the utility and versatility of our approaches, including endogenous CRISPR tags and ectopic labeling. By providing a guide for selecting the most suitable tools based on experimental goals, our work advances mitochondrial research in C. elegans and enhances the strategic integration of diverse imaging modalities for a holistic understanding of organelle dynamics in living organisms.

Circle of Willis and Its Anatomical Relevance

The Circle of Willis is an arterial network located at the base of the brain, formed by the interconnection of the anterior, middle, and posterior cerebral arteries, along with the anterior and posterior communicating arteries. It connects the internal carotid arteries to the vertebral arteries, allowing the distribution of cerebral blood flow. Its significance lies in its ability to offer an alternative pathway in cases of arterial obstruction, helping to prevent cerebral ischemia. However, anatomical variations of this structure are common, and only 20% to 25% of the population has a "complete" or symmetrical configuration. Such variations can influence the risk of cerebrovascular diseases, such as stroke, as they may compromise the efficiency of the compensatory mechanism. These anatomical variations have a direct impact on the diagnosis and treatment of neurological conditions. The integrity of the Circle of Willis can influence the severity of symptoms in cases of ischemic strokes, as well as affect aneurysm formation and its clinical implications. Advances in imaging techniques, such as CT angiography and magnetic resonance imaging, have enabled more accurate diagnoses and the development of more effective treatments for conditions associated with the Circle of Willis, making its anatomical understanding essential for the prevention and management of cerebrovascular diseases.

Tracer-Separator: A Deep Learning Model for Brain PET Dual-Tracer (18F-FDG and Amyloid) Separation.

Multiplexed PET imaging revolutionized clinical decision-making by simultaneously capturing various radiotracer data in a single scan, enhancing diagnostic accuracy and patient comfort. Through a transformer-based deep learning, this study underscores the potential of advanced imaging techniques to streamline diagnosis and improve patient outcomes. The research cohort consisted of 120 patients spanning from cognitively unimpaired individuals to those with mild cognitive impairment, dementia, and other mental disorders. Patients underwent various imaging assessments, including 3D T1-weighted MRI, amyloid PET scans using either 18F-florbetapir (FBP) or 18F-flutemetamol (FMM), and 18F-FDG PET. Summed images of FMM/FBP and FDG were used as proxy for simultaneous scanning of 2 different tracers. A SwinUNETR model, a convolution-free transformer architecture, was trained for image translation. The model was trained using mean square error loss function and 5-fold cross-validation. Visual evaluation involved assessing image similarity and amyloid status, comparing synthesized images with actual ones. Statistical analysis was conducted to determine the significance of differences. Visual inspection of synthesized images revealed remarkable similarity to reference images across various clinical statuses. The mean centiloid bias for dementia, mild cognitive impairment, and healthy control subjects and for FBP tracers is 15.70 ± 29.78, 0.35 ± 33.68, and 6.52 ± 25.19, respectively, whereas for FMM, it is -6.85 ± 25.02, 4.23 ± 23.78, and 5.71 ± 21.72, respectively. Clinical evaluation by 2 readers further confirmed the model's efficiency, with 97 FBP/FMM and 63 FDG synthesized images (from 120 subjects) found similar to ground truth diagnoses (rank 3), whereas 3 FBP/FMM and 15 FDG synthesized images were considered nonsimilar (rank 1). Promising sensitivity, specificity, and accuracy were achieved in amyloid status assessment based on synthesized images, with an average sensitivity of 95 ± 2.5, specificity of 72.5 ± 12.5, and accuracy of 87.5 ± 2.5. Error distribution analyses provided valuable insights into error levels across brain regions, with most falling between -0.1 and +0.2 SUV ratio. Correlation analyses demonstrated strong associations between actual and synthesized images, particularly for FMM images (FBP: Y = 0.72X + 20.95, R2 = 0.54; FMM: Y = 0.65X + 22.77, R2 = 0.77). This study demonstrated the potential of a novel convolution-free transformer architecture, SwinUNETR, for synthesizing realistic FDG and FBP/FMM images from summation scans mimicking simultaneous dual-tracer imaging.

Relative contribution of imaging techniques for the contemporary diagnosis of infective endocarditis: a single-center experience

Abstract Introduction In developed countries, the incidence of infective endocarditis (IE) is up to 6 cases per 100,000 individuals and in-hospital mortality rates are reported to reach 30%. The diagnostic recommendations for IE have been revised in the new ESC guidelines emphasizing the use of transesophageal echocardiography (TEE) and advanced imaging techniques (computed tomography [CT], magnetic resonance [MR], positron emission tomography [PET] and white blood cell scintigraphy [WBC-SPECT]). Aims This research aims to investigate the practical applicability of established clinical guidelines in a real-world population with suspected IE. Methods We reviewed the hospital database from 06/2021 to 06/2023 using the international classification of disease codification (ICD-10) for IE. Only patients admitted to Cardiology or Cardiac Surgery departments were included. Diagnosis of IE was defined according to the modified Duke criteria. Firstly, we identified individuals in whom diagnosis was performed by clinical presentation, blood cultures and transthoracic echocardiogram (TTE). Subsequently, we identified those who required further imaging diagnostic investigation. Results A total of 63 patients were included [mean age 64 ±14 years; 76% male (n=48)]. Native IE was diagnosed in 53 (84%) patients, prosthetic IE in 7 (11%) and cardiac implantable electronic devices-related IE in 3 (5%). A total of 26 (41%) patients had at least one predisposing risk factor, 48 (76%) presented with fever, 24 (38%) suffered an embolic event and 1 (2%) had an immunological phenomenon. Out of 49 positive blood cultures (78%), typical microorganisms consistent with IE were isolated in 25 (78%) of samples: 13 (34%) staphylococcus aureus, 10 (26%) oral streptococci, 9 (24%) enterococcus faecalis, 5 (13%) streptococcus gallolyticus and 1 (3%) HACEK group. Overall, in 22 (34%) patients, a definitive diagnosis of IE was established by means of clinical presentation, blood cultures and TTE. In the remaining, TEE was performed in 86% (n=36). Of those, a definite diagnosis was established in 52% (n=22). Brain and whole-body imaging upgraded the diagnosis from possible to definite in 3 (5%) patients. In the one patient in which a comprehensive clinical evaluation including TTE and TEE rejected IE, the diagnosis was ultimately established by means of PET. The median time from admission to the definite/possible diagnosis of IE was 6 (IQR 2-17) days. A total of 47 (75%) patients underwent surgery, with the most frequent indications being heart failure 46% (n=21) and uncontrolled infection 28% (n=13). Time from diagnosis to surgery was 10 (2-19) days, hospital length of stay was 45 (35-70) days and in-hospital mortality 21%. Conclusion Clinical presentation, blood cultures and TTE plus TEE established the definite or possible diagnosis of IE in most patients with suspected IE. Advanced imaging techniques allowed the establishment of definite diagnosis in only 6% of patients.

Super-Resolution Microscopy as a Versatile Tool in Probing Molecular Assembly

Molecular assembly is promising in the construction of advanced materials, obtaining structures with specific functions. In-depth investigation of the relationships between the formation, dynamics, structure, and functionality of the specific molecular assemblies is one of the greatest challenges in nanotechnology and chemistry, which is essential in the rational design and development of functional materials for a variety of applications. Super-resolution microscopy (SRM) has been used as a versatile tool for investigating and elucidating the structures of individual molecular assemblies with its nanometric resolution, multicolor ability, and minimal invasiveness, which are also complementary to conventional optical or electronic techniques that provide the direct observation. In this review, we will provide an overview of the representative studies that utilize SRM to probe molecular assemblies, mainly focusing on the imaging of biomolecular assemblies (lipid-based, peptide-based, protein-based, and DNA-based), organic–inorganic hybrid assemblies, and polymer assemblies. This review will provide guidelines for the evaluation of the dynamics of molecular assemblies, assembly and disassembly processes with distinct dynamic behaviors, and multicomponent assembly through the application of these advanced imaging techniques. We believe that this review will inspire new ideas and propel the development of structural analyses of molecular assemblies to promote the exploitation of new-generation functional materials.

Unveiling the Promise: Navigating Clinical Trials 1978–2024 for PDAC

Despite many decades of research, pancreatic ductal adenocarcinoma (PDAC) remains one of the most difficult cancers to diagnose and treat effectively. Although there have been improvements in the 5-year overall survival rate, it is still very low at 12.5%. The limited efficacy of current therapies, even when PDAC is detected early, underscores the aggressive nature of the disease and the urgent need for more effective treatments. Clinical management of PDAC still relies heavily on a limited repertoire of therapeutic interventions, highlighting a significant gap between research efforts and available treatments. Over 4300 clinical trials have been or are currently investigating different treatment modalities and diagnostic strategies for PDAC, including targeted therapies, immunotherapies, and precision medicine approaches. These trials aim to develop more effective treatments and improve early detection methods through advanced imaging techniques and blood-based biomarkers. This review seeks to categorize and analyze PDAC-related clinical trials across various dimensions to understand why so few chemotherapeutic options are available to patients despite the numerous trials being conducted. This review aims to provide a comprehensive and nuanced understanding of the landscape of PDAC-related clinical trials, with the overarching goal of identifying opportunities to accelerate progress in drug development and improve patient outcomes in the fight against this devastating disease.

Application of Advanced Microscopy Techniques to The Characterization of Mixed Matrix Membranes.

Mixed matrix membranes (MMMs) have emerged as promising materials for various separation processes due to their tunable properties, enhanced separation performance and reproducibility. In this review paper, we provide a comprehensive overview of the methodologies, challenges, and applications associated with the characterization of MMMs using two advanced imaging techniques: Focused Ion Beam Scanning Electron Microscopy (FIB-SEM) and Transmission Electron Microscopy (TEM). We begin by outlining the principles and capabilities of FIB-SEM and TEM, emphasizing their suitability for studying the microstructure, morphology, and composition of MMMs at nanoscale resolution. Subsequently, we discuss the specific challenges and limitations encountered in the characterization of MMMs using these techniques, including sample preparation, image acquisition, and data interpretation. Furthermore, we review the diverse applications of FIB-SEM and TEM in elucidating the structure-property relationships of MMMs. Through illustrative examples, we highlight the valuable insights gained from these imaging techniques in optimizing MMMs for various separation applications. Finally, we propose future directions and emerging trends in MMM characterization, including the integration of lasers into FIB-SEM and in situ characterization techniques, to address current challenges and push the boundaries of MMM design and performance.

Recent developments in non-invasive methods for assessing metabolic dysfunction-associated fatty liver disease

The prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD) is increasing, affecting over one-third of the global population and contributing to significant morbidity and mortality. Diagnosing MAFLD, especially with advanced fibrosis, remains challenging due to the limitations of liver biopsy, the current gold standard. Non-invasive tests are crucial for early detection and management. Among these, the fibrosis-4 index (Fib-4) is widely recommended as a first-line test for screening for liver fibrosis. Advanced imaging techniques, including ultrasound-based elastography and magnetic resonance elastography, offer high accuracy but are limited by cost and availability. Combining biomarkers, such as in the enhanced liver fibrosis score and FibroScan-AST score, enhances diagnostic precision and is recommended to further stratify patients who are considered to be intermediate or high risk from the Fib-4 score. We believe that the future lies in the combined use of biomarkers to improve diagnostic accuracy.

Enhancing spinal MRI segmentation with an asymmetric U-Net architecture

Spinal diseases are among the most prevalent health issues in modern society, significantly impacting patients’ quality of life. Diagnosing conditions such as disc herniation and spinal deformity requires advanced medical imaging techniques, including X-rays, magnetic resonance imaging (MRI), computed tomography, and nuclear magnetic resonance. Spine MRI is particularly crucial due to its ability to provide high-resolution images of soft tissues, essential for accurate diagnosis. However, the manual segmentation of spine MRI images is labor-intensive and inadequate for large-scale quantitative analysis. Thus, developing automated spinal MRI segmentation methods is critical to alleviating doctors’ workload and enhancing diagnostic efficiency. In this study, we propose a novel asymmetric U-Net architecture designed to improve the precision of reconstructing complex structures and details by increasing the depth of the upsampling side. The model incorporates adjacent-scale skip connections to control parameters while maintaining high segmentation accuracy. In addition, residual connections on the upsampling side prevent gradient vanishing, thereby enhancing the network’s feature learning and representation capabilities. Experimental results indicate that this method significantly reduces training time and increases model accuracy compared to traditional approaches, marking a substantial advancement in automated spinal MRI segmentation. This innovative approach holds promise for improving clinical outcomes and optimizing the workflow in medical imaging departments.

Intraoperative navigation in craniofacial surgery

Craniofacial surgery requires comprehensive anatomical knowledge of the head and neck to ensure patient safety and surgical precision. Over recent decades, there have been significant advancements in imaging techniques and the development of real-time surgical navigation systems. Intraoperative navigation technology aligns surgical instruments with imaging-derived information on patient anatomy, enabling surgeons to closely follow preoperative plans. This system functions as a radiologic map, improving the accuracy of instrument placement and minimizing surgical complications. The introduction of first-generation navigation systems in the early 1990s revolutionized surgical procedures by enabling real-time tracking of instruments using preoperative imaging. Initially utilized in neurosurgery, intraoperative navigation has since become standard practice in otolaryngology, cranio-maxillofacial surgery, and orthopedics. Since the 2000s, second-generation navigation systems have been developed to meet the growing demand for precision across various surgical specialties. The adoption of these systems in craniofacial surgery has been slower, but their use is increasing, particularly in procedures such as foreign body removal, facial bone fracture reconstruction, tumor resection, and craniofacial reconstruction and implantation. In Korea, insurance coverage for navigation in craniofacial surgery began in 2021, and new medical technologies for orbital wall fracture treatment were approved in August 2022. These technologies have only recently become clinically available, but are expected to play an increasingly important role in craniofacial surgery. Intraoperative navigation enhances operative insight, improves target localization, and increases surgical safety. Although these systems have a steep learning curve and initially prolong surgery, efficiency improves with experience. Calibration issues, registration errors, and soft tissue deformation can introduce inaccuracies. Nonetheless, navigation technology is evolving, and the integration of intraoperative computed tomography data holds promise for further enhancements of surgical accuracy. This paper discusses the various types and applications of navigation employed in craniofacial surgery, highlighting their benefits and limitations.

An improved convolutional architecture for quantitative characterization of pore networks in fine-grained rocks using FIB-SEM

Focused ion beam scanning electron microscope (FIB-SEM) is one of the most advanced imaging techniques for analyzing and understanding complex pore networks in shale and other fine-grained formations. However, FIB-SEM imaging tends to be time-consuming and labor-intensive and can result in biased interpretations associated with pore analysis. Recently, U-Net or its variants for image segmentation have been applied to capture microscopic pores at higher resolutions. The ‘traditional’ encoder-decoder-based approaches tend to detect very fine-scale microscopic pores poorly. This study presents an improved convolutional architecture for automatically analyzing pore structures in shale reservoirs using FIB-SEM. It does so by applying an overcomplete convolutional architecture, KiU-Net, to capture very fine-scale microscopic pores by accurately defining their edges in the input FIB-SEM images. The KiU-Net learns low and high-level features by making the model more sensitive to fine-scale microscopic pores in the input images. The purpose of this study is to demonstrate KiU-Net's capabilities by analyzing different shale formations with varying characteristics. The results indicate that KiU-Net is more accurate and efficient than other methods in predicting nanopores in the Longmaxi, Niutitang, Qingshankou, Qianjiang, and Yanchang Formations (China), Bakken shale (Canada), and coal reservoirs (China). Furthermore, KiU-Net demonstrated the advantage of requiring fewer parameters and achieving super convergence compared to the Attention U-Net technique. KiU-Net addresses the challenges of the Edge-Threshold Automatic Processing (ETAP) methods by capturing very fine-scale microscopic pores with accurate edges. This study further enhances the accuracy and efficiency of pore analysis in shales, thereby offering an improved method for understanding shale reservoir quality with the potential to improve petroleum recovery from such formations.

Cataract surgery with endothelial keratoplasty.

This review aims to provide an updated summary of the combined approach of cataract surgery with endothelial keratoplasty (EK), addressing key considerations, including intraocular lens (IOL) choice and calculation, decision between sequential and triple EK, and modifications in surgical techniques and postoperative management. Advances in imaging techniques (Scheimpflug tomography and anterior segment optical coherence tomography) have improved the ability to detect subclinical corneal edema, aiding in surgical decision-making for EK. Recent studies comparing sequential and triple-EK indicate that both methods yield similar visual outcomes. Though triple-EK offers quicker recovery, it may have higher complication rates. The use of gases like SF6 and C3F8 for anterior chamber tamponade is evolving, with conflicting findings on their efficacy in preventing graft detachment. Furthermore, IOL selection remains crucial, as hyperopic refractive surprises are common, and hydrophilic lenses should be avoided owing to the risk of opacification after EK. The combination of cataract surgery with EK has emerged as an effective treatment for patients with corneal endothelial diseases and cataract. Careful preoperative evaluation, appropriate IOL selection, and advances in surgical techniques contribute to better outcomes, although patient-specific factors must guide the choice between sequential and triple-EK procedures.

Tumor Hypoxia and Radioresistance

Tumor hypoxia is a prevalent feature of solid tumors, significantly contributing to increased tumor aggressiveness, metastatic potential, and resistance to conventional therapies such as radiotherapy. This review explores the complex relationship between tumor hypoxia and radioresistance, highlighting the molecular mechanisms involved and potential therapeutic strategies to enhance radiotherapy efficacy in hypoxic tumors. Key mechanisms include the role of hypoxia-inducible factors (HIFs), particularly HIF-1α, which regulates numerous genes involved in tumor survival, proliferation, and resistance under hypoxic conditions. The review also discusses the oxygen enhancement ratio (OER) and its impact on radiotherapy outcomes, emphasizing how hypoxia leads to reduced radiosensitivity by limiting the formation of radiation-induced DNA damage. Despite the development of various strategies to counteract hypoxia-induced radioresistance, such as HIF inhibitors, hypoxia-targeted gene therapy, and hypoxia-activated prodrugs (HAPs), clinical results have been mixed, necessitating further research. Additionally, advances in imaging techniques for detecting tumor hypoxia are explored, which may allow for more personalized radiotherapy approaches, such as dose painting. The future of overcoming tumor hypoxia in radiotherapy lies in the integration of innovative therapeutic strategies, personalized medicine, and improved imaging technologies, offering hope for enhanced treatment outcomes in cancer patients.

Spectrum of delayed post-hypoxic leukoencephalopathy syndrome: A systematic review

BACKGROUND Delayed post hypoxic leukoencephalopathy syndrome (DPHLS), also known as Grinker’s myelinopathy, is a rare but significant neurological condition that manifests days to weeks after a hypoxic event. Characterized by delayed onset of neurological and cognitive deficits, DPHLS presents substantial diagnostic and therapeutic challenges. AIM To consolidate current knowledge on pathophysiology, clinical features, diagnostic approaches, and management strategies for DPHLS, providing a comprehensive overview and highlighting gaps for future research. METHODS Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes guidelines, we systematically searched PubMed, ScienceDirect and Hinari databases using terms related to delayed post-hypoxic leukoencephalopathy. Inclusion criteria were original research articles, case reports, and case series involving human subjects with detailed clinical, neuroimaging, or pathological data on DPHLS. Data were extracted on study characteristics, participant demographics, clinical features, neuroimaging findings, pathological findings, treatment, and outcomes. The quality assessment was performed using the Joanna Briggs Institute critical appraisal checklist. RESULTS A total of 73 cases were reviewed. Common comorbidities included schizoaffective disorder, bipolar disorder, hypertension, and substance use disorder. The primary causes of hypoxia were benzodiazepine overdose, opioid overdose, polysubstance overdose, and carbon monoxide (CO) poisoning. Symptoms frequently include decreased level of consciousness, psychomotor agitation, cognitive decline, parkinsonism, and encephalopathy. Neuroimaging commonly revealed diffuse T2 hyperintensities in cerebral white matter, sometimes involving the basal ganglia and the globus pallidus. Magnetic resonance spectroscopy often showed decreased N-acetylaspartate, elevated choline, choline-to-creatinine ratio, and normal or elevated lactate. Treatment is often supportive, including amantadine, an antioxidant cocktail, and steroids. Hyperbaric oxygen therapy may be beneficial in those with CO poisoning. Parkinsonism was often treated with levodopa. Most of the patients had substantial recovery over the course of months and many cases had some residual neurocognitive deficits. CONCLUSION DPHLS remains a complex and multifaceted condition with various etiologies and clinical manifestations. Early recognition and appropriate management are crucial to improving patient outcomes. Future research should focus on standardizing diagnostic criteria, using advanced imaging techniques, and exploring therapeutic interventions to improve understanding and treatment of DPHLS. Conducting prospective cohort studies and developing biomarkers for early diagnosis and monitoring will be essential to advance patient care.

Advanced Imaging for Localized Prostate Cancer

Background/Objectives: Prostate cancer is a prevalent malignancy often presenting without early symptoms. Advanced imaging technologies have revolutionized its diagnosis and management. This review discusses the principles, benefits, and clinical applications of multiparametric magnetic resonance imaging (mpMRI), micro-ultrasound (microUS), and prostate-specific membrane antigen positron emission tomography–computed tomography (PSMA PET/CT) in localized prostate cancer. Methods: We conducted a comprehensive literature review of recent studies and guidelines on mpMRI, microUS, and PSMA PET/CT in prostate cancer diagnosis, focusing on their applications in biopsy-naïve patients, those with previous negative biopsies, and patients under active surveillance. Results: MpMRI has demonstrated high sensitivity and negative predictive value in detecting clinically significant prostate cancer (csPCa). MicroUS, a newer technology, has shown promising results in early studies, with sensitivity and specificity comparable to mpMRI. PSMA PET/CT has emerged as a highly sensitive and specific imaging modality, particularly valuable for staging and detecting metastatic disease. All three technologies have been incorporated into urologic practice for prostate cancer diagnosis and management, with each offering unique advantages in different clinical scenarios. Conclusions: Advanced imaging techniques, including mpMRI, microUS, and PSMA PET/CT, have significantly improved the accuracy of prostate cancer diagnosis, staging, and management. These technologies enable more precise targeting of suspicious lesions during biopsy and therapy planning. However, further research, especially randomized controlled trials, is needed to fully establish the optimal use and inclusion of these imaging modalities in various stages of prostate cancer care.

Advances and Challenges of Bioassembly Strategies in Neurovascular In Vitro Modeling: An Overview of Current Technologies with a Focus on Three-Dimensional Bioprinting.

Bioassembly encompasses various techniques such as bioprinting, microfluidics, organoids, and self-assembly, enabling advances in tissue engineering and regenerative medicine. Advancements in bioassembly technologies have enabled the precise arrangement and integration of various cell types to more closely mimic the complexity functionality of the neurovascular unit (NVU) and that of other biodiverse multicellular tissue structures. In this context, bioprinting offers the ability to deposit cells in a spatially controlled manner, facilitating the construction of interconnected networks. Scaffold-based assembly strategies provide structural support and guidance cues for cell growth, enabling the formation of complex bio-constructs. Self-assembly approaches utilize the inherent properties of cells to drive the spontaneous organization and interaction of neuronal and vascular components. However, recreating the intricate microarchitecture and functional characteristics of a tissue/organ poses additional challenges. Advancements in bioassembly techniques and materials hold great promise for addressing these challenges. The further refinement of bioprinting technologies, such as improved resolution and the incorporation of multiple cell types, can enhance the accuracy and complexity of the biological constructs; however, developing bioinks that support the growth of cells, viability, and functionality while maintaining compatibility with the bioassembly process remains an unmet need in the field, and further advancements in the design of bioactive and biodegradable scaffolds will aid in controlling cell adhesion, differentiation, and vascularization within the engineered tissue. Additionally, integrating advanced imaging and analytical techniques can provide real-time monitoring and characterization of bioassembly, aiding in quality control and optimization. While challenges remain, ongoing research and technological advancements propel the field forward, paving the way for transformative developments in neurovascular research and tissue engineering. This work provides an overview of the advancements, challenges, and future perspectives in bioassembly for fabricating neurovascular constructs with an add-on focus on bioprinting technologies.

Advances in clinical diagnosis and treatment of microsporidial keratitis

Microsporidia, a unicellular eukaryotic microorganism, poses a risk of infecting the eyes, precipitating microsporidia keratitis (MK). This condition typically manifests in two forms: microsporidian keratoconjunctivitis (MKC) or stromal keratitis (MSK). While MKC often resolves spontaneously, it can progress to MSK, a vision-threatening condition that, in severe instances, may lead to corneal perforation. Epidemiological studies reveal that MK is prevalent in Southeast Asia, particularly during the rainy season. Diagnosis encompasses a range of methods, including corneal scraping for microbiological analysis, PCR testing, and advanced imaging techniques such as AS-OCT and IVCM. Therapeutic approaches vary, with MKC typically managed through local and systemic drug therapy, while MSK may necessitate more aggressive interventions, including corneal transplantation. In China, MK case reports are scarce, and physicians still grapple with a lack of comprehensive understanding regarding its clinical presentation, diagnostic strategies, and treatment options. This deficit can lead to missed or misdiagnoses, as well as overtreatment. Consequently, this review endeavors to comprehensively outline the epidemiology, etiology, clinical features, diagnostic modalities, and therapeutic interventions for MK, thereby offering valuable insights and guidance for clinical practice.

Comprehensive Review of Post-treatment Imaging in Head and Neck Cancers: From expected to unexpected and beyond.

Head and neck cancer management requires multidisciplinary approach in which radical surgery with or without flap reconstructions and neck dissection, along with radiotherapy (RT)/chemoradiotherapy (CRT) serve as the key components. Neoadjuvant chemotherapy (NACT) and immunotherapy are used in selected cases based on the institutional preference. Knowledge of expected posttreatment changes on imaging is essential to differentiate it from recurrence. In addition, awareness of various posttreatment complications is imperative for their early detection on imaging. Distorted anatomy after treatment poses diagnostic challenge, hence, proper choice of imaging modality and appropriate timing of scan is pertinent for accurate posttreatment evaluation. In this article, we have provided a comprehensive review on expected imaging appearances post RT/CRT and after major types of head and neck squamous cell carcinoma (HNSCC) surgeries. In addition, we have extensively reviewed the imaging appearances of various posttreatment complications, and recurrences at the primary and lymph nodal sites. We have also delved into the patterns of recurrence in human papillomavirus (HPV) positive HNSCC in this article. Furthermore, we have provided flowcharts and discussed recommendations on the site-specific and treatment related imaging modalities to be used along with their appropriate timing, for adequate evaluation of HNSCC after treatment. We have also reviewed posttreatment reporting of imaging findings using Neck Imaging Reporting and Data Systems (NIRADS) and Hopkins criteria. In addition, we have also touched upon the role of advanced imaging techniques for posttreatment HNSCC evaluation.

ESR Essentials: role of PET/CT in neuroendocrine tumors-practice recommendations by the European Society for Hybrid, Molecular and Translational Imaging.

Neuroendocrine neoplasms (NEN) originate from the secretory cells of the neuroendocrine system, with the majority arising in the gastrointestinal tract and pancreas. Given the heterogeneity in the biological behavior and morphological differentiation of these tumors, advanced imaging techniques are crucial for supporting the suspected diagnosis, accurate staging, and monitoring therapy. As most well-differentiated NEN demonstrate overexpression of somatostatin receptors (SSR) on the cell surface, SSR-directed PET/CT is considered the reference standard for imaging of this particular entity. SSR-PET/CT should be the imaging method of choice in every NEN G1 or G2 and considered for re-staging after both potentially curative and non-curative surgeries. The extent of SSR expression is also crucial for determining a patient's eligibility for peptide receptor radionuclide therapy (PRRT). PRRT utilizes [177Lu]Lu-DOTA-TATE to target the SSR receptor and can significantly prolong progression-free survival in patients with advanced, progressive neuroendocrine tumor of the gastroenteropancreatic system (GEP-NET). PET/CT is a central component of the multidisciplinary management of NEN. Variable follow-up intervals are recommended, considering that tumors with higher proliferation rates or advanced metastatic disease require more frequent assessments. The combination with other imaging modalities, like MRI, complements SSR-PET/CT, further enhancing overall diagnostic accuracy. KEY POINTS: Somatostatin receptor-PET/CT (SSR-PET/CT) is the guideline-recommended reference standard for imaging well-differentiated neuroendocrine tumors (NET). SSR-PET/CT should be the diagnostic imaging of choice for staging and post-therapy re-staging of grade 1 or 2 NET (G1 or G2). Variable follow-up intervals are recommended for NET G1 and G2. Tumors with higher proliferation rates or advanced metastatic disease necessitate more frequent assessments.