Distribution Of Blood Vessels Research Articles

Correlations between blood vessel distribution, lung function and structural change in idiopathic pulmonary fibrosis.

Correlations between the image analysis of CT scan, lung function and quality of life in patients with idiopathic pulmonary fibrosis (IPF) remain unclear. This study aimed to investigate the impacts of pulmonary blood-vessel distribution and the extent of fibrosis on the lung function and quality of life of patients with IPF. Patients were enrolled in an IPF registry and had completed pulmonary function tests, chest HRCT, St. George Respiratory Questionnaire (SGRQ) and echocardiography. Pulmonary blood-vessel distribution, specific image-derived airway volume (siVaw) and fibrosis extent (siVfib) were quantitatively calculated by functional respiratory imaging on HRCT. The study subjects were categorized into DLco <40% pred. (n = 40) and DLco ≥40% pred. (n = 19) groups. Patients with DLco <40% pred. had significantly higher scores of SGRQ, composite physiologic index (CPI), exercise oxygen desaturation (∆SpO2), siVaw, lower FVC% pred. and 6-minute walking distance% pred. The proportion of small blood vessels in the upper lobes (BV5PR-UL) was significantly correlated with CPI, DLco % Pred., FVC% pred., SGRQ and ∆SpO2. Only BV5PR-UL had a significant impact on all indices but not BV5PR in the lower lobes (BV5PR-LL). siVfib was significantly negatively correlated with BV5PR-UL, DLco% pred. and FVC% pred., as well as positively correlated with CPI, ∆SpO2 and siVaw. BV5PR-UL and siVfib had significant correlations with lung function and may become important indicators to assess the severity of IPF and the impact on quality of life.

Lymphatic and blood vessels in parathyroid tumors: Immunohistochemical study with LYVE-1 and von Willebrand factor.

Parathyroid tumors exhibit distinct histopathological features that differentiate benign from malignant lesions. This study aimed to study characteristic distribution of lymphatic and blood vessels in normal parathyroid gland and parathyroid tumors to distinguish cancer from benign tumors. Immunohistochemical staining for lymphatic and blood vessels and parathyroid hormone was performed with parathyroid proliferating lesions including adenoma, multiglandular multiple adenomas, atypical tumor, and carcinoma. Lymphatic vessels were immunostained with lymphatic vessel endothelial receptor 1 (LYVE-1) and blood vessels were immunostained with von Willebrand factor (vWf). Normal parathyroid gland contained several round blood vessels with less linear lymphatic vessels. The less parathormone-immunostained adenomas weighing less than 2 g revealed larger blood vessels with perivascular small linear lymphatic vessels, and the larger adenomas contained proportionally larger blood vessels. Smaller multiglandular multiple adenomas were like smaller adenomas with less parathormone staining and contained larger, round blood vessels with perivascular small linear lymphatic vessels. Larger multiglandular multiple adenomas weighing more than 4 g and one atypical tumor contained nodular pattern consisted of alternating strongly parathormone-positive lobes and negative lobes with numerous, dilated blood vessels and perivascular linear lymphatic vessels. Both primary and metastatic carcinomas were strongly and diffusely positive for parathyroid hormone with numerous lymphatic and blood vessels at the invading margin. Thus, normal parathyroid has rich blood vessels which provide accessibility of minced tissues seeding for auto-transplantation. Immunostaining patterns of parathyroid hormone, lymphatic and blood vessels help to distinguish carcinoma from benign parathyroid proliferating lesions. The negative immunohistochemical staining for parafibromin will detect carriers of hyperparathyroidism-jaw tumor (HPT-JT) syndrome and would help in diagnosing parathyroid cancer in both HPT-JT carriers and sporadic patients.

Facial vascular visualization enhancement based on optical detection technology.

This study aims to develop a facial vascular enhancement imaging system and analyze vascular distribution in the facial region to assess its potential in preventing unintended intravascular injections during cosmetic facial filling procedures. A facial vascular enhancement imaging system based on optical detection technology was designed, and volunteers were recruited. The system was utilized to detect and analyze vascular distribution in various anatomical regions of the faces. The vascular visualization-enhanced images generated by the system were compared with visible light images to validate the vascular visualization capability of the system. Additionally, the reliability of vascular visualization was assessed by comparing the observed vascular patterns in the vascular visualization-enhanced images with those in near-infrared light images. Thirty volunteers were recruited. The vascular visualization-enhanced images produced by the system demonstrated a significant capacity to identify vascular morphology and yielded a higher vessel count compared to visible light images, particularly in the frontal, orbital, perioral, mental, temporal, cheek, and parotid masseter regions (p < 0.05). The temporal region exhibited the highest vascular density, followed by the cheek region and then the frontal region. Reliability analysis of vascular visualization enhancement indicated that the system's imaging of facial vasculature not only demonstrated reliability but also enhanced physicians' visual perception. Blood vessel distribution varies across facial regions. The facial vascular enhancement imaging system facilitates real-time and clear visualization of facial vasculature, offering immediate visual feedback to surgeons. This innovation holds promise for enhancing the safety and effectiveness of facial filling procedures.

Cr3+ doped Cs2ZnCl4 microcrystals enabling near-infrared emission

As a promising lead-free metal halide, Cs2ZnCl4 has the potential to serve as a host for achieving various photoluminescence emissions with different colors through ion doping. Therefore, studying the optical properties of various ions doped into Cs2ZnCl4 with tetrahedron coordination is of great significance. However, there is still a lack of research on near-infrared (NIR) emission in Cs2ZnCl4. In this study, we successfully synthesized Cs2ZnCl4:Cr3+ crystals using a simple hydrothermal method. The Cs2ZnCl4:Cr3+ exhibits luminescence in the range of 800–1300 nm, with a peak position at 915 nm and a full width at half maximum (FWHM) of 150 nm under 375 nm excitation. Through the analysis of photoluminescence spectra, density functional theory (DFT), lifetime decay curves, temperature-dependent spectra, and time-resolved photoluminescence (TRPL), we confirmed the presence of two potential sites for Cr3+ ion occupancy. Additionally, NIR phosphor-converted light-emitting diodes (pc-LEDs) were fabricated by combining Cs2ZnCl4:Cr3+ with a green LED chip. The night-vision camera captured the distribution of blood vessels and bones in the fingers, demonstrating the promising potential of this material in the field of NIR imaging.

Topological insight of immune-vascular distribution in peri-implantitis lesions.

To characterize the distribution of macrophages, neutrophils, NK cells, and blood vessels in peri-implantitis compared to healthy aged gingiva samples. This observational study included eight gingival samples from peri-implantitis and eight from periodontally healthy individuals. By immunofluorescence were identified neutrophils, NK cells, macrophages, and their pro-inflammatory or pro-healing phenotypes, and blood vessels. Two ROIs were designated as zone 1, connective tissue closest to the epithelium and zone 2, connective tissue over 200 microns from the rete ridges. Immune cells and vascular structures were quantified and characterized according to their distribution in both zones. Two peri-implantitis zones were characterized by unique macrophage phenotypes and blood vessel architecture. Blood vessels were larger in zone 2 in peri-implantitis. A greater number of NK cells and macrophages were found in peri-implantitis compared to healthy aged samples. A higher presence of pro-inflammatory macrophages was found in zone 1 compared to zone 2. A similar proportion of pro-inflammatory and pro-healing macrophages were found in zone 2. A specific distribution for pro-inflammatory macrophages and vascular architecture is observed in peri-implantitis. TNF-α colocalizes with macrophages in the connective tissue near rete ridges. NK cells are more abundant in peri-implantitis than in healthy samples.

Stealing-like phenomenon with interscalene nerve block and its influence on the regional blood flow during shoulder arthroscopic surgery

Background Hypotensive anesthesia during shoulder arthroscopy is mandatory. Hypotension in the supine or decubitus position is safe and effective for reducing blood losses and for maintaining a clear surgical field. However, in the beach chair position, major complications have been reported. The current study claims that the alignment of the vessel in these regions favor a stealing-like phenomenon associated with interscalene block. This phenomenon has a good impact on the surgical field. Results There was a significant change in the peak systolic velocity between the two populations with values of 57±5 in group I versus 90±12 in group G, with a clearer surgical field in group I than in group G. The need for the intraoperative adjuvant analgesics was higher in group G (29 patients) compared with group I (10 patients) as was the pain score at early postoperative intervals of 6 and 12 h. Conclusion The distribution of blood vessels in this region favors a stealing-like phenomenon may be because of the associated vasoplegic effect with the interscalene nerve block, yielding a favorable surgical field without deliberate hypotension.

Visualizing cortical blood perfusion after photothrombotic stroke in vivo by needle-shaped beam optical coherence tomography angiography

Optical imaging techniques provide low-cost, non-radiative images with high spatiotemporal resolution, making them advantageous for long-term dynamic observation of blood perfusion in stroke research and other brain studies compared to non-optical methods. However, high-resolution imaging in optical microscopy fundamentally requires a tight optical focus, and thus a limited depth of field (DOF). Consequently, large-scale, non-stitched, high-resolution images of curved surfaces, like brains, are difficult to acquire without z-axis scanning. To overcome this limitation, we developed a needle-shaped beam optical coherence tomography angiography (NB-OCTA) system, and for the first time, achieved a volumetric resolution of less than 8 μm in a non-stitched volume space of 6.4 mm × 4 mm × 620 μm in vivo. This system captures the distribution of blood vessels at 3.4-times larger depths than normal OCTA equipped with a Gaussian beam (GB-OCTA). We then employed NB-OCTA to perform long-term observation of cortical blood perfusion after stroke in vivo, and quantitatively analyzed the vessel area density (VAD) and the diameters of representative vessels in different regions over 10 days, revealing different spatiotemporal dynamics in the acute, sub-acute and chronic phase of post-ischemic revascularization. Benefiting from our NB-OCTA, we revealed that the recovery process is not only the result of spontaneous reperfusion, but also the formation of new vessels. This study provides visual and mechanistic insights into strokes and helps to deepen our understanding of the spontaneous response of brain after stroke.

Tissue mimicking materials and finger phantom design for pulse oximetry.

Pulse oximetry represents a ubiquitous clinical application of optics in modern medicine. Recent studies have raised concerns regarding the potential impact of confounders, such as variable skin pigmentation and perfusion, on blood oxygen saturation measurement accuracy in pulse oximeters. Tissue-mimicking phantom testing offers a low-cost, well-controlled solution for characterizing device performance and studying potential error sources, which may thus reduce the need for costly in vivo trials. The purpose of this study was to develop realistic phantom-based test methods for pulse oximetry. Material optical and mechanical properties were reviewed, selected, and tuned for optimal biological relevance, e.g., oxygenated tissue absorption and scattering, strength, elasticity, hardness, and other parameters representing the human finger's geometry and composition, such as blood vessel size and distribution, and perfusion. Relevant anatomical and physiological properties are summarized and implemented toward the creation of a preliminary finger phantom. To create a preliminary finger phantom, we synthesized a high-compliance silicone matrix with scatterers for embedding flexible tubing and investigated the addition of these scatterers to novel 3D printing resins for optical property control without altering mechanical stability, streamlining the production of phantoms with biologically relevant characteristics. Phantom utility was demonstrated by applying dynamic, pressure waveforms to produce tube volume change and resultant photoplethysmography (PPG) signals. 3D printed phantoms achieved more biologically relevant conditions compared to molded phantoms. These preliminary results indicate that the phantoms show strong potential to be developed into tools for evaluating pulse oximetry performance. Gaps, recommendations, and strategies are presented for continued phantom development.

Shikonin Inhibits Vascular Extravasation and Inflammation in Burn Wounds by Regulating Wnt/β-Catenin Pathway

Objective: To explore whether shikonin can alleviate vascular leakage in burn wounds, inhibit skin inflammation, and exert protective effects on skin. Methods: A mouse skin burn wound model was routinely established, and fluorescent microspheres were injected through the tail vein 2 h before sampling to characterize the degree of vascular leakage. Dorsal skin was obtained by surgical dissection and embedded in OCT, and frozen sections were prepared. CD31 immunofluorescence was used to determine the distribution of blood vessels in burnt skin, and Ly6G immunofluorescence staining was used to determine the level of neutrophil recruitment in the skin. Results: Skin microvessels were mainly distributed in the dermis. We found that severe vascular leakage occurred in the blood vessels of the burned dermis, and shikonin significantly alleviated vascular leakage in the burned area. Furthermore, shikonin significantly inhibited neutrophil recruitment to burn sites. Most importantly, we also found that shikonin can alleviate vascular leakage and inhibit skin inflammation at burn sites through the Wnt/β-catenin signaling pathway. Conclusion: Shikonin can alleviate vascular leakage, and inhibit skin inflammation in burn wounds through the Wnt/β-catenin signaling pathway. This experimental study provides a proof-of-concept and a new avenue for the repair and treatment of burn skin vascular injuries.

Networks of Nerve Fibers, and Blood and Lymphatic Vessels in the Mouse Auricle: The Structural Basis of Ear Acupuncture.

Ear acupuncture, as a system for treating and preventing diseases through stimulation of points on the auricle, has been systematically introduced during the last 60 years. Although the auricular cartography was described somatotopically as an inverted fetus by Paul Nogier, MD, the underlying mechanism of auricular stimulation remains unclear. The aim of this research was to gain an understanding of the structural basis of auricular stimulation, as well as showing the distribution of the nerve fibers, and the blood and lymphatic vessels. The distribution of nerve fibers, and blood and lymphatic vessels was examined in whole-mount auricular skins of mice by combining the biomarkers protein gene product 9.5, cluster of differentiation 31, and lymphatic-vessel endothelial hyaluronan receptor-1 following tissue-clearing treatment with multiple immunofluorescent staining. The labeled nerve fibers, and the blood and lymphatic vessels were distributed extensively in the inner and outer parts of the auricular skin. Auricular nerves aligning with blood vessels ran from the basal region to the peripheral region and crossed over lymphatic vessels, thus forming the neural, vascular, and lymphatic networks. As these are important tissue components of auricular skin, this result implies that the auricular nerve fibers, and blood and lymphatic vessels may coordinate with each other to respond directly to auricular stimulation.

Probing the glioma microvasculature: a case series of the comparison between perfusion MRI and intraoperative high-frame-rate ultrafast Doppler ultrasound

BackgroundWe aimed to describe the microvascular features of three types of adult-type diffuse glioma by comparing dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI) with intraoperative high-frame-rate ultrafast Doppler ultrasound.MethodsCase series of seven patients with primary brain tumours underwent both DSC perfusion MRI and intra-operative high-frame-rate ultrafast Doppler ultrasound. From the ultrasound images, three-dimensional vessel segmentation was obtained of the tumour vascular bed. Relative cerebral blood volume (rCBV) maps were generated with leakage correction and normalised to the contralateral normal-appearing white matter. From tumour histograms, median, mean, and maximum rCBV ratios were extracted.ResultsLow-grade gliomas (LGGs) showed lower perfusion than high-grade gliomas (HGGs), as expected. Within the LGG subgroup, oligodendroglioma showed higher perfusion than astrocytoma. In HGG, the median rCBV ratio for glioblastoma was 3.1 while astrocytoma grade 4 showed low perfusion with a median rCBV of 1.2. On the high-frame-rate ultrafast Doppler ultrasound images, all tumours showed a range of rich and organised vascular networks with visually apparent abnormal vessels, even in LGG.ConclusionsThis unique case series revealed in vivo insights about the microvascular architecture in both LGGs and HGGs. Ultrafast Doppler ultrasound revealed rich vascularisation, also in tumours with low perfusion at DSC MRI. These findings warrant further investigations using advanced MRI postprocessing, in particular for characterising adult-type diffuse glioma.Relevance statementOur findings challenge the current assumption behind the estimation of relative cerebral blood volume that the distribution of blood vessels in a voxel is random.Key points• Ultrafast Doppler ultrasound revealed rich vascularity irrespective of perfusion dynamic susceptibility contrast MRI state.• Rich and organised vascularisation was also observed even in low-grade glioma.• These findings challenge the assumptions for cerebral blood volume estimation with MRI.Graphical

Deep learning-based automated pipeline for blood vessel detection and distribution analysis in multiplexed prostate cancer images.

Introduction: Prostate cancer is a highly heterogeneous disease, presenting varying levels of aggressiveness and response to treatment. Angiogenesis is one of the hallmarks of cancer, providing oxygen and nutrient supply to tumors. Micro vessel density has previously been correlated with higher Gleason score and poor prognosis. Manual segmentation of blood vessels (BVs) In microscopy images is challenging, time consuming and may be prone to inter-rater variabilities. In this study, an automated pipeline is presented for BV detection and distribution analysis in multiplexed prostate cancer images. Methods: A deep learning model was trained to segment BVs by combining CD31, CD34 and collagen IV images. In addition, the trained model was used to analyze the size and distribution patterns of BVs in relation to disease progression in a cohort of prostate cancer patients (N = 215). Results: The model was capable of accurately detecting and segmenting BVs, as compared to ground truth annotations provided by two reviewers. The precision (P), recall (R) and dice similarity coefficient (DSC) were equal to 0.93 (SD 0.04), 0.97 (SD 0.02) and 0.71 (SD 0.07) with respect to reviewer 1, and 0.95 (SD 0.05), 0.94 (SD 0.07) and 0.70 (SD 0.08) with respect to reviewer 2, respectively. BV count was significantly associated with 5-year recurrence (adjusted p = 0.0042), while both count and area of blood vessel were significantly associated with Gleason grade (adjusted p = 0.032 and 0.003 respectively). Discussion: The proposed methodology is anticipated to streamline and standardize BV analysis, offering additional insights into the biology of prostate cancer, with broad applicability to other cancers.

Assessing the histomorphology, and microscopic composition of the triangular fibrocartilage complex [TFCC] of the wrist joint: A cadaveric observational study

TFCC, being a complicated structure, located on the ulnar side of the wrist is composed of multiple distinct anatomic entities which together play a critical role in wrist biomechanics. The anatomy of TFCC has not been extensively studied in the Indian population. To elucidate the microscopic anatomy and composition of the triangular fibrocartilage complex of the wrist joint using haematoxylin-eosin and Verhoff Van Gieson staining methods. Samples collected from 40 specimens (20 right and 20 left limbs) were placed in 10% neutral buffered formalin for fixation. Paraffin-embedded blocks were prepared and tissue sections were taken at 7-micron thickness. The slides were subjected to H&amp;E and VVG staining following standardized protocol. The morphological structure of the seven components of triangular fibrocartilage complexes was assessed. The articular disc consisted of densely packed interlaced fibrocartilage with sparse blood vessels. Radioulnar ligaments showed densely-packed-parallel or interlaced- collagen-bundles. A mixture of tight and loose parallel tissue was observed in the sub-sheath of the extensor carpi ulnaris muscle, the ulnar-triquetral (UTL), and the ulnar-lunate ligament (ULL). Irregular morphological composition and loose connective tissue predominated in the ulnar-carpal meniscus (UCM). Blood vessels were observed in the epi-fascicular/ fascicular areas of the UTL, interstitial region of ULL and UCM. The microscopic anatomy of TFCC was complex owing to the varied nature of its entities. An understanding of the distribution of connective tissue, blood vessels, and elastic fibres would be of immense help in planning arthroscopic procedures.

Distribution of neurovascular structures within the prostate gland and their relationship to complications after radical prostatectomy.

Radical prostatectomy remains the main choice of treatment for prostate cancer. However, despite improvements in surgical techniques and neurovascular sparing procedures, rates of erectile dysfunction, and urinary incontinence remain variable. This is due, at least in part, to an incomplete understanding of neurovascular structures associated with the prostate. The objective of this study was to provide a comprehensive, detailed histological overview of the distribution of nerves and blood vessels within the prostate, facilitating subsequent correlation of prostatic neurovascular structures with patients' clinical outcomes after radical prostatectomy. Neurovascular structures within the prostate were investigated in a total of 309 slides obtained from 15 patients who underwent non-nerve-sparing radical prostatectomy. Immunohistochemical staining was performed to identify and distinguish between parasympathetic and sympathetic nerves, whereas hematoxylin and eosin staining was used to identify blood vessels. The total number, density, and relative position of nerves and blood vessels were established using quantitative morphometry and illustrated using visualization approaches. Patient-specific outcome data were then used to establish whether the internal distribution of nerves and blood vessels within the prostate correlated with the nature and extent of complications after surgery. One-way analysis of variance tests and unpaired ttests were applied to establish statistically significant differences across the measured variables. Nerves and blood vessels were present across all prostatic levels and regions. However, their number and density varied considerably between regions. Assessment of the precise positioning of neurovascular structures revealed that the majority of nerve fibers were located within the dorsal and peripheral aspects of the gland. In contrast, blood vessels were predominantly located within ventral and dorsal midline regions. The number of intraprostatic nerves was found to be significantly lower in patients who recovered their continence within 12 months of surgery, compared to those whose recovery took 12 months or longer. We report an unexpected disconnect between the localization and positioning of nerve fibers and blood vessels within the prostate. Moreover, individual variability in the density of intraprostatic neurovascular structures appears to correlate with the successful recovery of urinary continence after radical prostatectomy, suggesting that differences in intrinsic neurovascular arrangements of the prostate influence postoperative outcomes.

Analysis of the vascular patterns of 52 amelanotic cutaneous melanoma metastases: A prospective descriptive study

Background/Aim. Early diagnosis of amelanotic cutaneous melanoma metastases (ACMM) represents a great challenge and is essential for determining the stage, treatment, and prognosis of the disease. The aim of the study was to evaluate the vascular structures and their arrangement and frequency in ACMM. Methods. The study was conducted as a prospective, descriptive, multicenter study of pathohistologically confirmed ACMM. Results. The study included a total of 52 ACMM from 17 patients (8 men and 9 women, with an age range of 32-91 years, median 63.12 years) with a previous history of primary melanoma. The most prevalent were elevated ACMM - 39 (75.0%) lesions, while 13 (25.0%) ACMM were flat. Linear irregular blood vessels were statistically significantly more often associated with elevated ACMM, compared to flat ACMM (92.3% vs. 50.0%, p &lt; 0.001). Dotted blood vessels were statistically significantly more frequent in flat ACMM, compared to elevated ACMM (76.9% vs. 28.2%, p = 0.003). Diffuse distribution of blood vessels was the most prevalent, with 92.3% of flat ACMM and 76.9% of elevated ACMM (p = 0.416). Peripheral arrangement of blood vessels was detected in 15.4% of elevated ACMM and 7.7% of flat ACMM (p = 0.815). The central arrangement of blood vessels was seen in 2.6%, while the cluster (segmental) schedule was present in 5.1% of elevated ACMM. The monomorphic vascular pattern was the predominant pattern in 84.6% of flat ACMM and 61.5% of elevated ACMM (p = 0.232). Conclusion. Our study supports the finding that linear irregular blood vessels are more commonly associated with elevated ACMM, while the dotted ones are dominant in flat ACMM.

Development of NIR-II small animal living fluorescence imaging system

Fluorescence imaging technology can dynamically monitor gene and cell changing in live animals in real-time, with advantages such as high sensitivity, high resolution, and non-invasion. In recent years, it has been widely used in tumor research, gene expression research, drug development research, etc. The imaging wavelength of traditional fluorescence imaging technology falls in the visible and near-infrared-I region. Due to the absorption and scattering effects of light propagation in biological tissues, and the inherent fluorescence of biological tissues, traditional fluorescence imaging techniques still have significant limitations in penetration depth and image signal-to-noise ratio. In this work, a highly integrated near-infrared-II (NIR-II, 900—1880 nm) small animal living fluorescence imaging system is developed by taking the advantages of NIR-II fluorescence imaging technology, such as low absorption, low scattering, and deep penetration depth in biological tissues. And a method of enhancing and correcting fluorescence image is proposed to optimize fluorescence images. In this work, the biological tissue simulation experiments and live animal experiments are conducted to test the performance and imaging effect of the system. The experimental results show that the system has the advantages of deep penetration depth, high signal-to-noise ratio, and high sensitivity. Combined with commercial indocyanine green reagents and aggregation-induced emission dyes, this system can monitor the distribution of blood vessels in real time and continuously monitor deep tissues and organs in mice, and conduct the dynamically monitoring research in living mice in a conscious state. This helps to promote tumor research and drug development research in the field of biomedical imaging to enter a new stage.

In vivo burn scar assessment with speckle decorrelation and joint spectral and time domain optical coherence tomography.

Post-burn scars and scar contractures present significant challenges in burn injury management, necessitating accurate evaluation of the wound healing process to prevent or minimize complications. Non-invasive and accurate assessment of burn scar vascularity can offer valuable insights for evaluations of wound healing. Optical coherence tomography (OCT) and OCT angiography (OCTA) are promising imaging techniques that may enhance patient-centered care and satisfaction by providing detailed analyses of the healing process. Our study investigates the capabilities of OCT and OCTA for acquiring information on blood vessels in burn scars and evaluates the feasibility of utilizing this information to assess burn scars. Healthy skin and neighboring scar data from nine burn patients were obtained using OCT and processed with speckle decorrelation, Doppler OCT, and an enhanced technique based on joint spectral and time domain OCT. These methods facilitated the assessment of vascular structure and blood flow velocity in both healthy skin and scar tissues. Analyzing these parameters allowed for objective comparisons between normal skin and burn scars. Our study found that blood vessel distribution in burn scars significantly differs from that in healthy skin. Burn scars exhibit increased vascularization, featuring less uniformity and lacking the intricate branching network found in healthy tissue. Specifically, the density of the vessels in burn scars is 67% higher than in healthy tissue, while axial flow velocity in burn scar vessels is 25% faster than in healthy tissue. Our research demonstrates the feasibility of OCT and OCTA as burn scar assessment tools. By implementing these technologies, we can distinguish between scar and healthy tissue based on its vascular structure, providing evidence of their practicality in evaluating burn scar severity and progression.

CCL2 chemokine inhibition primes the tumor vasculature for improved nanomedicine delivery and efficacy

Blood vessel functionality is crucial for efficient tumor-targeted drug delivery. Heterogeneous distribution and perfusion of angiogenic blood vessels contribute to suboptimal accumulation of (nano-) therapeutics in tumors and metastases. To attenuate pathological angiogenesis, an L-RNA aptamer inhibiting the CC motif chemokine ligand 2 (CCL2) was administered to mice bearing orthotopic 4T1 triple-negative breast cancer tumors. The effect of CCL2 inhibition on tumor blood vessel functionality and tumor-targeted drug delivery was evaluated via multimodal and multiscale optical imaging, employing fluorophore-labeled polymeric (10 nm) and liposomal (100 nm) nanocarriers. Anti-CCL2 treatment induced a dose-dependent anti-angiogenic effect, reflected by a decreased relative blood volume, increased blood vessel maturity and functionality, and reduced macrophage infiltration, accompanied by a shift in the polarization of tumor-associated macrophages (TAM) towards a less M2-like and more M1-like phenotype. In line with this, CCL2 inhibitor treatment improved the delivery of polymers and liposomes to tumors, and enhanced the antitumor efficacy of free and liposomal doxorubicin. Together, these findings demonstrate that blocking the CCL2-CCR2 axis modulates TAM infiltration and polarization, resulting in vascular normalization and improved tumor-targeted drug delivery.

Placenta segmentation in magnetic resonance imaging: Addressing position and shape of uncertainty and blurred placenta boundary

Automatic segmentation of the placenta in MRI facilitates quantitative measurements and further analysis. Automatic segmentation of the placenta in magnetic resonance imaging (MRI) is challenging due to the fact that (1) the position of the placenta varies greatly in different views of MRI. In addition, the shape of the placenta changes layer by layer in different MRI slices. The position and shape of the placenta are highly uncertain. (2) PAS results in a blurred placental boundary. To address the above issues, a refinement fusion based on the U-Net (RFU-Net) is proposed for the segmentation of the placenta with variable position and shape in MR images, and the boundary de-precision explores the distribution of blood vessels around the placental boundary. In RFU-Net, ResNet34 is used as a feature extractor, and a fusion multiscale feature (FMF) is proposed to extract multiscale features and their contextual information to solve the problem of variable placental shape. A refinement segmentation module (RSM) is designed to provide information about the position of the placenta to solve the problem of variable placental position, which effectively improves the segmentation of the placenta. The mean intersection over union (MIoU), hausdorff distance (HD), dice coefficient (Dice) and accuracy (Acc) are 0.8620, 4.3142, 0.9314 and 0.9987, respectively. Extensive experiments show that RFU-Net effectively improves the segmentation accuracy of the placenta. Boundary de-precision resolves the blurring of placental boundaries, effectively highlighting areas of the placental boundary that may contain blood vessels to aid in the physician's diagnosis.

Superb microvascular imaging for evaluation of microvascularity in breast nodules compared with conventional Doppler imaging.

Neovascularity visualization in breast nodules is challenging due to the limitations of conventional Doppler imaging methods. This study aims to assess the performance of superb microvascular imaging (SMI) in evaluating the microvascularity of breast nodules (diameter ≤2 cm). The comparison of performances of SMI with color Doppler flow imaging (CDFI) and power Doppler imaging (PDI) was made by using a three-factor scoring system of vascularity. This study also investigated the common features of microvascularity in small malignant nodules on SMI for early differentiating from benign nodules. Ninety-one female patients (with 125 breast nodules) were enrolled in this retrospective study. All the breast nodules were examined by grayscale ultrasonography (US), CDFI, PDI, and SMI. The number, morphologic features, and distribution of blood vessels were scored to evaluate the nodular vascularity in light of the three-factor scoring system. The diagnostic value of SMI for microvascularity in breast nodules was analyzed and compared with CDFI and PDI. Histological analysis showed 53 malignant and 72 benign nodules. The vascularity grades detected by SMI were significantly different from those of CDFI and PDI (P<0.05). SMI detected 47 grade-IV nodules of the total 125 nodules (37.6%), which was more than those detected by CDFI (10.4%, 13/125) and PDI (12.8%, 16/125), while more grade-I nodules were detected by CDFI (42.4%, 53/125) and PDI (36.8%, 46/125) compared with SMI (21.6%, 27/125). Differences in the vessel number, morphologic features, and distribution between benign and malignant breast nodules were significant on SMI (P<0.05). The vessel number ≥6, penetrating vessels, and a mixed distribution of vessels in peripheral and central nodular tissues were the common features of microvascularity in the grade-IV malignant nodules on SMI, whereas the blood vessels in the benign nodules were straight and branching and peripherally distributed. In comparison with CDFI and PDI, SMI enhances microvascularity detection, depicts the microvascular architecture in breast nodules and has potential in the differential diagnosis of malignant nodules from benign nodules.