Abstract: Methods and systems for infusing a cooled infusate to a target location in a patient are described. A temperature of the blood and infusate admixture upstream of the catheter as well as at other locations along the catheter may be monitored and a feedback system utilized to control the volume, temperature, and/or infusion rate of the infusate so as to achieve a predetermined temperature at the target location. Control may also be based on the patient's native vessel flow rate. The system may monitor or calculate hematocrit upstream of the catheter and adjust infusion so as to provide sufficient oxygenation of the blood and infusate admixture. The system may also monitor reflux of the infusate past a distal end of the catheter and reduce infusion upon the detection of reflux.

Abstract: The present application provides systems that include a controller, and an insertion device with at least one temperatures sensor thereon and a pump coupled to the controller. The insertion device provides temperature measurement(s) at/of a subject's organ to the controller and the controller varies an infusate flow rate to induce temperature changes in at least a portion of the subject's organ and stores the temperature measurements during perfusion induced temperature changes on a memory device. The controller may estimate at least one hemodynamic characteristic of at least a portion of the subject's organ based on the temperature measurements obtained during perfusion induced temperature changes.

Abstract: Methods and systems for infusing a cooled infusate to a target location in a patient are described. A temperature of the blood and infusate admixture upstream of the catheter as well as at other locations along the catheter may be monitored and a feedback system utilized to control the volume, temperature, and/or infusion rate of the infusate so as to achieve a predetermined temperature at the target location. Control may also be based on the patient's native vessel flow rate. The system may monitor or calculate hematocrit upstream of the catheter and adjust infusion so as to provide sufficient oxygenation of the blood and infusate admixture. The system may also monitor reflux of the infusate past a distal end of the catheter and reduce infusion upon the detection of reflux.

Abstract: Methods and systems for infusing a cooled infusate to a target location in a patient are described. A temperature of the blood and infusate admixture upstream of the catheter as well as at other locations along the catheter may be monitored and a feedback system utilized to control the volume, temperature, and/or infusion rate of the infusate so as to achieve a predetermined temperature at the target location. Control may also be based on the patient's native vessel flow rate. The system may monitor or calculate hematocrit upstream of the catheter and adjust infusion so as to provide sufficient oxygenation of the blood and infusate admixture. The system may also monitor reflux of the infusate past a distal end of the catheter and reduce infusion upon the detection of reflux.

Abstract: A method and apparatus for determining a temperature differential at a portion of a patient's body utilizing temperature sensitive MRI measurements. A diagnostic fluid bolus is administered into a blood vessel of the patient, wherein the diagnostic fluid bolus has a diagnostic fluid bolus temperature waveform. MRI measurements are used to determine the thermodiluted temperature waveform of the diagnostic fluid bolus at a target site in the body spaced away from the administration site. The temperature differential may be used to determine a cardiovascular parameter.

Abstract: A method for producing an image of a blood vessel in a patient utilizing temperature sensitive MRI measurement. The method includes introducing a fluid in a blood vessel, obtaining magnetic resonance information from the blood vessel, and determining a magnetic resonance parameter using the magnetic resonance information. The method further includes using the magnetic resonance parameter to determine a temperature differential in the blood vessel and producing an image of the blood vessel based on the temperature differential. Systems for producing an image of a blood vessel in a patient using temperature sensitive MRI measurements are also provided.

Abstract: A method for determining a cardiovascular parameter in a portion of a body of a patient utilizing temperature sensitive MRI measurements. The method includes obtaining magnetic resonance information from a portion of a body of a patient and determining a magnetic resonance parameter using the magnetic resonance information. The method further includes using the magnetic resonance parameter to determine a temperature differential in the portion of the body and determining a cardiovascular parameter using the temperature differential.

Abstract: A method for determining a metabolic rate of a portion of a body of a patient. The method includes obtaining magnetic resonance information from the portion of the body after introduction of a fluid and determining a magnetic resonance parameter using the magnetic resonance information. The method further includes using the magnetic resonance parameter to determine a temperature differential in the portion of the body and using the temperature differential to determine a metabolic rate of the portion of the body.

Abstract: Methods and systems for infusing a cooled infusate to a target location in a patient are described. A temperature of the blood and infusate admixture upstream of the catheter as well as at other locations along the catheter may be monitored and a feedback system utilized to control the volume, temperature, and/or infusion rate of the infusate so as to achieve a predetermined temperature at the target location. Control may also be based on the patient's native vessel flow rate. The system may monitor or calculate hematocrit upstream of the catheter and adjust infusion so as to provide sufficient oxygenation of the blood and infusate admixture. The system may also monitor reflux of the infusate past a distal end of the catheter and reduce infusion upon the detection of reflux.