Ultrasound Localization Microscopy (ULM) can resolve the microvascular bed down to a few micrometers. To achieve such performance, microbubble contrast agents must perfuse entire network. Microbubbles are then located individually and tracked over time sample individual vessels, typically hundreds of thousands images. overcome fundamental limit diffraction dense reconstruction network, low concentrations be used, which leads acquisitions lasting several minutes. Conventional processing...

The resolution of 3D Ultrasound Localization Microscopy (ULM) is determined by acquisition parameters such as frequency and transducer geometry but also microbubble (MB) concentration, which linked to the total time needed sample vascular tree at different scales. In this study, we introduce a novel anatomically-realistic ULM simulation framework based on two-photon microscopy (2PM) in-vivo MB perfusion dynamics. As proof concept, using metrics localization error, count network filling,...

Generating computational anatomical models of cerebrovascular networks is vital for improving clinical practice and understanding brain oxygen transport. This achieved by extracting graph-based representations based on pre-mapping vascular structures. Recent graphing methods can provide smooth vessels trajectories well-connected topology. However, they require water-tight surface meshes as inputs. Furthermore, adding radii information their graph compartments restricts alignment along...

Microvascular stalling, the process occurring when a capillary temporarily loses perfusion, has gained increasing interest in recent years through its demonstrated presence various neuropathologies. Studying impact of such stalls on surrounding brain tissue is paramount importance to understand their role diseases. Despite efforts trying study stalling events, investigations are hampered by elusiveness and scarcity. In an attempt alleviate these hurdles, we present here novel methodology...

Given known correlations between vascular health and cognitive impairment, the development of tools to image microvasculature in whole brain could help investigate these correlations. We explore feasibility using an automated serial two-photon microscope fluorescent gelatin-filled rodent brains three-dimensions (3-D) with goal carrying group studies. Vascular density (VD) was computed automatic segmentation combined coregistration techniques build a group-level metric brain. Focusing on...

Perturbations in the microcirculatory system have been observed neurological conditions, such as Alzheimer's disease or systemic inflammation. However, changes occurring at level of capillary are difficult to translate biomarkers that could be measured macroscopically.

An automated dual-resolution serial optical coherence tomography (2R-SOCT) scanner is developed. The histology system combines a low-resolution ( 25 μm/voxel ) 3× OCT with high-resolution 1.5 40× to acquire whole mouse brains at low resolution and target specific regions of interest (ROIs) high resolution. ROIs positions are selected either manually by the microscope operator or using an ROI positioning selection algorithm. Additionally, multimodal multiresolution registration pipeline...

Recent advancements in sources and detectors operating the NIR-II wavelengths have driven emergence of intrinsic microscopy. These significant technological strides were necessary because longer are known to experience reduced scattering absorption biological tissue. Leveraging this optical advantage, application spectral domain microscopy holds potential improve depth imaging preserve coherence depth. In study, we showcase integration phase-contrast into a reflectance confocal microscope...

In this study, an automated serial two-photon microscope was used to image a fluorescent gelatin filled rodent's brain in 3D. A method compute vascular density using automatic segmentation combined with coregistration techniques build group-level vasculature metrics. By studying the medial prefrontal cortex and hippocampal formation of 3 age groups (2, 4.5 8 months old), we compared for both WT Alzheimer model transgenic (APP/PS1). We observe loss caused by ageing process propose further...

In this work, we demonstrate the application of Rose Bengal as a photo-thrombotic agent using 2-photon and 3-photon excitation by measuring response to multiphotonic excitation. We also demonstrate, in case excitation, that mechanism used is different from laser injury alone with control group FitC injected mice. Preliminary results show capillary photo-thrombosis could be performed up 200 μm OCT imaging confirm blockage.

To obtain an accurate representation of a brain structural connectivity, diffusion MRI and fiber tracking depend on good understanding white matter structures. Although the methods work well when performed in single orientation bundles, most are limited more complex cases, especially to take into account crossing, fanning, kissing fibers. A recent international challenge concluded that algorithms generated 4–5 times false positive tracks than true average. This was attributed large part lack...

Ultrasound Localization Microscopy (ULM) can map vessels at the capillary scale (<10 μm) by acquiring tens of thousands images in which injected microbubbles are detected and tracked to generate super-resolved blood vessel maps. However, our knowledge, there no validation frameworks for ULM image formation algorithms. Herein, we developed a 3-D, anatomically realistic simulation tool based on serial two-photon microscopy (STPM). Rodent brain vasculature was segmented from STPM [1]...

Abstract The resolution of 3D Ultrasound Localization Microscopy (ULM) is determined by acquisition parameters such as frequency and transducer geometry but also microbubble (MB) concentration, which linked to the total time needed sample vascular tree at different scales. In this study, we introduce a novel anatomically- physiologically-realistic ULM simulation framework based on two-photon microscopy (2PM) in-vivo MB perfusion dynamics. As proof concept, using metrics localization error,...

Generating computational anatomical models of cerebrovascular networks is vital for improving clinical practice and understanding brain oxygen transport. This achieved by extracting graph-based representations based on pre-mapping vascular structures. Recent graphing methods can provide smooth vessels trajectories well-connected topology. However, they require water-tight surface meshes as inputs. Furthermore, adding radii information their graph compartments restricts alignment along...

Two-photon microscopy (TPM) can provide a detailed microscopic information of cerebrovascular structures. Extracting anatomical vascular models from TPM angiograms remains tedious task due to image degeneration associated with acquisitions and the complexity microvascular networks. Here, we propose fully automated pipeline capable providing useful structures captured TPM. In proposed method, segment blood vessels using convolutional neural network employ resulting binary labels create an...