Abstract: A sclerosing embolizing hydrogel comprising from about 0.1% by weight to about 4.0% by weight of chitosan; from about 0.01M to about 1M of hydrochloric acid; from 0% by volume to about 40% by volume of iopamidol; from 0.5% by weight to about 25% by weight of ?-glycerophosphate disodium salt; and from about 0.05% by weight to about 4% by weight of sodium tetradecyl sulphate. Also a kit for synthesizing the hydrogel and a method using the hydrogel to treat a vascular defect in a subject.

Abstract: A sclerosing embolizing hydrogel comprising from about 0.1% by weight to about 4.0% by weight of chitosan; from about 0.01M to about 1M of hydrochloric acid; from 0% by volume to about 40% by volume of iopamidol; from 0.5% by weight to about 25% by weight of ?-glycerophosphate disodium salt; and from about 0.05% by weight to about 4% by weight of sodium tetradecyl sulphate. Also a kit for synthesizing the hydrogel and a method using the hydrogel to treat a vascular defect in a subject.

Abstract: A magnetic resonance imager (MRI) controllably propels at least one magnetic field responsive body within a subject. The MRI comprises a bore magnet producing an intense magnetic field sufficient to magnetically saturate the magnetic field responsive body. A magnetic field gradient generator is configured to apply variable magnetic gradients to at least a portion of the subject containing the magnetically-saturated body. A controller instructs the magnetic field gradient generator to acquire image data of the magnetically-saturated body within the subject and to apply a calculated magnetic gradient that will propel the magnetically-saturated body towards a target location in the subject. A tracking unit of the MRI provides position feedback information of the magnetically-saturated body within the subject.

Abstract: The present invention generally relates to intravascular ultrasound (IVUS) image segmentation methods, and is more specifically concerned with an intravascular ultrasound image segmentation method for characterizing blood vessel vascular layers. The proposed image segmentation method for estimating boundaries of layers in a multi-layered vessel provides image data which represent a plurality of image elements of the multi-layered vessel. The method also determines a plurality of initial interfaces corresponding to regions of the image data to segment and further concurrently propagates the initial interfaces corresponding to the regions to segment. The method thereby allows to estimate the boundaries of the layers of the multi-layered vessel by propagating the initial interfaces using a fast marching model based on a probability function which describes at least one characteristic of the image elements.

Abstract: The method for vascular elastography comprises: i) obtaining a sequence of radio-frequency (RF) images including pre-tissue-motion and post-tissue-motion images in digital form of a vessel delimited by a vascular wall; the pre-tissue-motion and post-tissue-motion images being representative of first and second time-delayed configuration, of the whole vessel; ii) partitioning both the pre-tissue-motion and post-tissue-motion images within the vascular wall into corresponding data windows; approximating a trajectory between the pre- and post-tissue-motion for corresponding data windows; and using the trajectory for each data window to compute the full strain tensor in each data window, which allow determining the Von Mises coefficient. The method can be adapted for non-invasive vascular elastography (NIVE), for non-invasive vascular micro-elastography (MicroNlVE) on small vessels, and for endovascular elastography (EVE).

Abstract: A multimodality imaging phantom is disclosed which is useful for calibrating devices for imaging vascular conduits. The phantom is compatible with X-ray, ultrasound and magnetic resonance imaging techniques. It allows testing, calibration, and inter-modality comparative study of imaging devices, in static or dynamic flow conditions. It also provides a geometric reference for evaluation of accuracy of imaging devices. The tissue-mimicking material is preferably an agar-based solidified gel. A vessel of known desired geometry runs throughout the gel and is connected to an inlet and outlet at its extremities for generating a flow circulation in the vessel. Said phantom also contains fiducial markers detectable in the above-mentioned modalities. The markers are preferably made of glass and are embedded in a layer of agar gel containing a fat component.

Abstract: A method for segmenting elements on an image, comprising: i) creating an active contour from at least one identified point on the image; ii) defining a reference intensity value from the pixels of the active contour; iii) simplifying the image by comparing the pixels of the image to the reference intensity value to give a propagation value to the pixels of the image; and iv) propagating the active contour in a selected one of an expansion/contraction direction as a function of the propagation value of the pixels adjacent to the active contour in the image; wherein ii), iii) and iv) are repeated in the selected direction whereby the active contour finally represents the element segmented in the image.

Abstract: The method for vascular elastography comprises: i) obtaining a sequence of radio-frequency (RF) images including pre-tissue-motion and post-tissue-motion images in digital form of a vessel delimited by a vascular wall; the pre-tissue-motion and post-tissue-motion images being representative of first and second time-delayed configuration, of the whole vessel; ii) partitioning both the pre-tissue-motion and post-tissue-motion images within the vascular wall into corresponding data windows; approximating a trajectory between the pre- and post-tissue-motion for corresponding data windows; and using the trajectory for each data window to compute the full strain tensor in each data window, which allow determining the Von Mises coefficient. The method can be adapted for non-invasive vascular elastography (NIVE), for non-invasive vascular micro-elastography (MicroNIVE) on small vessels, and for endovascular elastography (EVE).

Abstract: The present invention generally relates to intravascular ultrasound (IVUS) image segmentation methods, and is more specifically concerned with an intravascular ultrasound image segmentation method for characterizing blood vessel vascular layers. The proposed image segmentation method for estimating boundaries of layers in a multi-layered vessel provides image data which represent a plurality of image elements of the multi-layered vessel. The method also determines a plurality of initial interfaces corresponding to regions of the image data to segment and further concurrently propagates the initial interfaces corresponding to the regions to segment. The method thereby allows to estimate the boundaries of the layers of the multi-layered vessel by propagating the initial interfaces using a fast marching model based on a probability function which describes at least one characteristic of the image elements.

Abstract: A blood clot filter (10) comprises a number of diverging legs (26) extending from a common central hub (16) to define a blood clot reservoir. Adjacent legs (26) share a common root (18) from which branches off at least two main branches (24). Each main branch (24) connects at a distal end to an adjacent main branch (24) to form a plurality of interconnected anchoring members (30a, 30b) about an open upstream end of the blood clot reservoir.

Abstract: A multimodality imaging phantom is disclosed which is useful for calibrating devices for imaging vascular conduits. The phantom is compatible with X-ray, ultrasound and magnetic resonance imaging techniques. It allows testing, calibration, and inter-modality comparative study of imaging devices, in static or dynamic flow conditions. It also provides a geometric reference for evaluation of accuracy of imaging devices. The tissue-mimicking material is preferably an agar-based solidified gel. A vessel of known desired geometry runs throughout the gel and is connected to an inlet and outlet at its extremities for generating a flow circulation in the vessel. Said phantom also contains fiducial markers detectable in the above-mentioned modalities. The markers are preferably made of glass and are embedded in a layer of agar gel containing a fat component.

Abstract: Described is a method and system for propelling and controlling displacement of a microrobot through a patient's blood vessel. The microrobot is formed with a body containing field-of-force responsive material wherein, in response to a field of force, the material undergoes a force in the direction of a gradient of the field of force. The microrobot is positioned in a blood vessel for displacement through the blood vessel, and a field of force with a given gradient is generated and applied to the microrobot in view of propelling the microrobot through the blood vessel in the direction of the gradient of the field of force. A direction and amplitude of the gradient of the field of force is calculated to thereby control displacement of the microrobot through the patient's blood vessel.

Abstract: A multimodality imaging phantom is disclosed in the present invention. This multimodality imaging phantom is particularly useful for calibrating devices for imaging vascular conduits. The phantom is compatible with X-ray, ultrasound and magnetic resonance imaging techniques. It allows testing, calibration, and inter-modality comparative study of imaging devices, in static or dynamic flow conditions. It also provides a geometric reference for evaluation of accuracy of imaging devices. The tissue-mimicking material is preferably an agar-based solidified gel. A vessel of known desired geometry runs throughout the gel and is connected to an inlet and outlet at its extremities for generating a flow circulation in the vessel. Using a lost-material casting technique, complex realistic geometry (including 3D configurations with no symmetry axis or plane) of normal or diseased vessel can be modeled. Said phantom also contains fiducial markers detectable in the above-mentioned modalities.