Novadaq Technologies Ulc

Johns Hopkins University

National Research Council of Canada

Stryker Corporation

Stryker European Operations Limited

Novadaq Technologies, Inc.

Akorn, Inc.

Akora, Inc.

Robert W Flower

Arthur E Bailey

Robert Anthony Stead

John C Docherty

Gurpreet Mangat

Abu Alam

Seshadri M Chari

Mark Hewko

Ashok J Chavan

Douglas R Carroll

Mark Hewco

John C Doherty

Ronn Kling

Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Facilitating assessment of blood flow and tissue perfusion using fluorescence-mediated photoplethysmography

A method, an apparatus, and a kit including the apparatus and a fluorescence agent are provided for measuring a time-varying change in an amount of blood in a tissue volume, and include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain a measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent. There is further provided a fluorescence agent for use in the method.

Quantification of absolute blood flow in tissue using fluorescence-mediated photoplethysmography

A method and an apparatus for measuring a time-varying change in an amount of blood in a tissue include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain the measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent.

Quantification of absolute blood flow in tissue using fluorescence mediated photoplethysmography

Endoscopic identification and dissection of a blood vessel in tissue during endoscopic harvest can be enhanced by injecting a bolus of ICG into the bloodstream, illuminating the target vessels with excitation light capable of exciting fluorescence in the ICG, and locating the vessel to be harvested by observing the ICG fluorescence. Moreover, collapsed blood vessel may be harvested by inserting an endoscope into the collapsed blood vessel, injecting into the collapsed blood vessel a bolus containing ICG to re-inflate the blood vessel, illuminating the target vessels with excitation light capable of exciting fluorescence in the ICG; and locating the re-inflated blood vessel by observing the ICG fluorescence.

Near infra red fluorescence imaging for visualization of blood vessels during endoscopic harvest

There is provided a method and a system for quantification of absolute blood flow in tissue using near-infrared fluorescence angiography in conjunction with photoplethysmography (fluorescence-mediated photoplethysmography). The method and system of the present invention provide absolute, real-time measurements of flow in terms of volume/time/area based upon measurement of fluorescence intensity.

Disclosed herein are methods, kits, and compositions for medical imaging relating to fluorescent dyes entrapped in erythrocytes. Also disclosed therein are methods, and compositions further comprising erythrocytes entrapping at least one therapeutically active agent, as well as methods for releasing the entrapped therapeutically active agent(s). Disclosed herein also are methods for preparation of the cells entrapping dye and therapeutically active agent(s) in a freeze-dried form that makes them readily available and easy to use in a clinical environment.

Methods for production and use of substance-loaded erythrocytes (S-IEs) for observation and treatment of microvascular hemodynamics

Method for assessing the patency of a patient's blood vessel, advantageously during or after treatment of that vessel by an invasive procedure, comprising administering a fluorescent dye to the patient; obtaining at least one angiographic image of the vessel portion; and evaluating the at least one angiographic image to assess the patency of the vessel portion. Other related methods are contemplated, including methods for assessing perfusion in selected body tissue, methods for evaluating the potential of vessels for use in creation of AV fistulas, methods for determining the diameter of a vessel, and methods for locating a vessel located below the surface of a tissue.

Method and apparatus for performing intra-operative angiography

Disclosed herein are compositions and methods for imaging nerve cells. The composition comprises a fluorescent dye; and a viral component selected from a neurotropic, replication-defective virus, a viral protein of a neurotropic virus, and a capsid of a neurotropic virus. Although the fluorescent dye in itself cannot penetrate nerve cells, the fluorescent dye is bound to the viral component to form a dye/viral component complex that is capable of penetrating nerve cells.

Imaging methods and compositions comprising fluorescent dyes associated with viral components for nerve imaging

A method for treating a lesion of an animal, the animal having at least one vessel that carries blood to the lesion, comprising locating the vessel, administering a composition comprising a photodynamic agent, applying energy to the vessel to photocoagulate the vessel and thereby reduce the rate at which the treatment composition exits said lesion and applying energy to said lesion, of a type and an amount sufficient to excite the photodynamic agent, causing the lesion to undergo photodynamic therapy. Preferably, a dye that is both a fluorescent dye and a radiation absorbing dye, such as indocyanine green dye, is added to the treatment composition to allow (a) confirmation of the presence of the treatment composition in the lesion to be detected by fluorescent angiography and (b) the rate of blow flow to be reduced in the blood vessel feeding the lesion using dye enhanced photocoagulation.

Combined photocoagulation and photodynamic therapy

Aqueous indocyanine green (ICG) composition exhibiting enhanced stability, as well as enhanced ICG concentration, as compared to presently available ICG products. The composition comprises an aqueous ICG composition comprising ICG at a concentration of at least about 10 mg/ml and an aqueous diluent, wherein the composition is stable for at least 24 hours. Diagnostic and therapeutic methods for using these aqueous compositions are also contemplated, e.g., angiography, dye-enhanced photocoagulation, photodynamic therapy, for a variety of conditions, including Age-Related Macular Degeneration (ARMD), lesions and tumors.

Growing community of inventors

Hunt Valley, MD, United States of America

Robert W Flower