Patient-specific analysis of raw positron emission tomography data

Abstract

Systems and methods are provided for evaluating tissue for abnormal glucose uptake within a region of interest within a patient. A PET scanner obtains PET imagery including the region of interest and at least part of the liver. An SUV calculator calculates a first set of SUVs representing the region of interest and a second set SUVs representing the liver from the set of at least one PET image. A standardization component calculates a correction value as a function of the second set of SUVs and applies the correction value to either a decision threshold associated with the region of interest or the first set of SUVs. A diagnosis component compares the first set of SUVs to the decision threshold to determine if the glucose uptake within the region of interest is abnormal. A display provides the determination to a user.

Having described the invention, we claim: 
     
         1 . A system for evaluating tissue for abnormal glucose uptake within a region of interest within a patient, the system comprising:
 a positron emission tomography (PET) scanner configured to obtain a set of at least one PET image that includes a first set of at least one intensity value representing the region of interest and a second set of at least one intensity value representing a liver of the patient;   a standardization component configured to calculate a correction value as a function of the second set of at least one intensity value and apply the correction value to a chosen one of a decision threshold associated with the region of interest and the first set of at least one intensity value;   a diagnosis component configured to compare the first set of intensity values to the decision threshold associated with the region of interest to determine if the glucose uptake within the region of interest is abnormal; and   a display configured to display the determination if the glucose uptake within the region of interest is abnormal to a user.   
     
     
         2 . The system of  claim 1 , wherein the standardization component is configured to calculate a ratio including a value representing the second set of at least intensity value and an average liver standard uptake value (SUV) for a population of patients. 
     
     
         3 . The system of  claim 2 , wherein the population of patients used to determine the average liver SUV is a proper subset of all patients for whom measured SUVs of the liver are available, the proper subset being selected according to at least one biometric parameter with the patient. 
     
     
         4 . The system of  claim 2 , wherein the average liver SUV for a population of patients is in a range between 1.5 and 3. 
     
     
         5 . The system of  claim 2 , wherein the standardization component is configured to calculate the correction value as a product of the ratio and a scaling factor. 
     
     
         6 . The system of  claim 2 , wherein the standardization component is configured to calculate the correction value as the sum of the ratio and an offset value. 
     
     
         7 . The system of  claim 1 , wherein the diagnosis component calculates the decision threshold associated with the region of interest as a function of a previously measured intensity value that has been corrected by a previously calculated correction factor. 
     
     
         8 . The system of  claim 1 , wherein the diagnosis component selects the decision threshold associated with the region of interest according to a type of tissue associated with the region of interest. 
     
     
         9 . The system of  claim 1 , wherein the standardization component calculates the second set of at least one intensity value by selecting an intensity value for each of a plurality of regions within the hepatic parenchyma and calculating a mean value for the selected intensity values across the plurality of regions to provide a mean intensity value representing the liver. 
     
     
         10 . The system of  claim 1 , wherein the PET scanner is a positron emission tomography/computed tomography (PET-CT) scanner configured to provide PET and CT data for the region of interest and the liver. 
     
     
         11 . A method for evaluating tissue for abnormal glucose uptake within a region of interest within a patient, the method comprising:
 performing a positron emission tomography (PET) scan at an associated PET scanner to provide a first set of at least one intensity value representing the region of interest and a second set of at least one intensity value representing a liver of the patient;   calculating a correction value as a function of the second set of at least one intensity value;   applying the correction value to a chosen one of a decision threshold associated with the region of interest and the first set of at least one intensity value; and   comparing the first set of at least one intensity value to the decision threshold associated with the region of interest.   
     
     
         12 . The method of  claim 11 , wherein calculating a correction value as a function of the second set of at least one intensity value comprises calculating a ratio including a value representing the second set of at least one intensity value and an average liver SUV for a population of patients. 
     
     
         13 . The method of  claim 11 , wherein the decision threshold associated with the region of interest comprises a function of a previously measured intensity value that has been corrected by a previously calculated correction factor. 
     
     
         14 . The method of  claim 11 , wherein calculating the second set of at least one intensity value representing the liver comprises:
 selecting a plurality of regions within the hepatic parenchyma within the PET image of the liver;   determining an intensity value for each of the plurality of regions; and   calculating a mean value for the determined intensity values across the plurality of regions to provide a mean intensity value representing the liver.   
     
     
         15 . The method of  claim 11 , wherein performing a positron emission tomography (PET) scan at an associated PET scanner comprises performing a positron emission tomography/computed tomography (PET-CT) scan at an associated PET scanner to provide PET and CT data for the region of interest and the liver. 
     
     
         16 . The method of  claim 11 , wherein comparing the first set of at least one intensity value to the decision threshold associated with the region of interest comprises determining an average value of the first set of at least one intensity value and comparing the average value to the decision threshold. 
     
     
         17 . The method of  claim 16 , wherein applying the correction value to a chosen one of a decision threshold associated with the region of interest and the first set of at least one intensity value comprises applying the correction value to the average value. 
     
     
         18 . The method of  claim 16 , wherein applying the correction value to a chosen one of a decision threshold associated with the region of interest and the first set of at least one intensity value comprises applying the correction value to each of the first set of at least one intensity value before determining an average value of the first set of at least one intensity value. 
     
     
         19 . A system comprising an operatively connected set of at least one non-transitory computer readable medium, each non-transitory medium being operatively connected to at least one associated processor and storing machine executable instructions, executable by the at least one associated processor to evaluate tissue for abnormal glucose uptake within a region of interest within a patient, the machine executable instructions comprising:
 a client interface configured to receive a first set of at least one intensity value representing the region of interest and a second set of at least one intensity value from the hepatic parenchyma;   a standardization component configured to calculate a correction value as a function of the second set of at least one intensity value and apply the correction value to a chosen one of a decision threshold associated with the region of interest and the first set of at least one intensity value; and   a diagnosis component configured to compare the first set of at least one intensity value to the decision threshold associated with the region of interest to determine if the glucose uptake within the region of interest is abnormal;   wherein the client interface is configured to provide the determination if the glucose uptake within the region of interest is abnormal to an associated client device.   
     
     
         20 . The system of  claim 19 , wherein the standardization component is configured to calculate a ratio including a value representing the second set of at least one intensity value and an average liver SUV for a population of patients.