Evaluating disease progression using magnetic resonance imaging

Abstract

An orthopedic magnetic resonance imaging system is disclosed. This system includes a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient. A segmentation module segments surfaces in the joint based on information contained within at least one of the data sets, and a registration module spatially registers, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient. A comparison module detects differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions. A cross-patient comparison module can compare detected differences for the patient with detected differences for at least one other patient.

1 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions, and of a cross-patient comparison module responsive to the comparison module to compare detected differences for the patient with detected differences for at least one other patient.    
     
     
         2 . The apparatus of  claim 1  further including a multi-patient database and wherein the cross-patient comparison module includes a statistical analysis module operative to derive statistical information about the progression of disease in the joints of a number of patients.  
     
     
         3 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, wherein the registration module is operative to spatially register the data sets to within an average root-mean-square value of about 10 microns, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         4 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, wherein the registration module is operative to spatially register the data sets to within an average root-mean-square value of about 50 microns, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         5 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, wherein the registration module includes an automatic registration module operative to perform at least a three-dimensional preliminary spatial registration independent of user input, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         6 . The apparatus of  claim 5  wherein the registration module is operative to perform the registration based on previously acquired magnetic resource imaging data for the same patient.  
     
     
         7 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, wherein the segmentation module is an automatic segmentation module responsive to the source of magnetic resonance imaging data sets and operative to automatically segment anatomical features in the patient with substantially only supervisory and artifact-correcting user input, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         8 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, wherein the source of magnetic resonance imaging data is operative to provide data sets optimized for the detection of at least bone and cartilage, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         9 . The apparatus of  claim 8  wherein the source of magnetic resonance imaging data includes a magnetic resonance imaging system operative to acquire the data sets using a sequence is less than about  30  minutes in duration.  
     
     
         10 . The apparatus of  claim 8  wherein the joint is a load-bearing joint, and wherein the imaging data sets include imaging data for at least the majority of the load bearing surfaces of the joint.  
     
     
         11 . The apparatus of  claim 8  wherein the segmentation module employs an active contour algorithm.  
     
     
         12 . The apparatus of  claim 11  wherein the segmentation module employs a subpixel active contour algorithm.  
     
     
         13 . The apparatus of  claim 11  wherein the segmentation module employs an active contour algorithm configured to segment open contours with minimal operator intervention.  
     
     
         14 . The apparatus of  claim 11  wherein the segmentation module employs a three-dimensional gradient-driven active contour algorithm.  
     
     
         15 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, wherein the source of magnetic resonance imaging data sets includes a magnetic resonance imaging system and a support assembly operative to immobilize the diseased joint within the magnetic resonance imaging system with the joint at a predetermined three-dimensional position, and wherein the support assembly is operative to repeatedly immobilize the joint at predetermined three-dimensional positions that fall within a range of less than 7 millimeters along the longitudinal axis of the magnetic resonance imaging system, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         16 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, wherein the source of magnetic resonance imaging data sets includes a magnetic resonance imaging system and a support assembly operative to immobilize the diseased joint within the magnetic resonance imaging system with the joint at a predetermined three-dimensional position, and wherein the support assembly is operative to repeatedly immobilize the joint at predetermined three-dimensional positions that fall within a range of less than 17 millimeters along the longitudinal axis of the magnetic resonance imaging system, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         17 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions, and of a differential display module operative to generate a difference map depicting differences between the data sets detected by the comparison module.    
     
     
         18 . A method of monitoring disease progression in a joint, comprising: 
 obtaining successive images of a same joint for each of a plurality of patients, wherein at least some of the joints are diseased, and    obtaining a processed data set expressing results of segmenting joint surfaces within at least one of the images for each patient, of, for each of the patients, spatially registering joint features for one of the successive images with another of the successive images, of detecting differences between the successive images for each of the individual patients, and of comparing the differences obtained for different ones of the patients.    
     
     
         19 . The method of  claim 18  wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of administering a therapeutic agent to at least some of the patients before the acquisition of at least some of the successive images, and of evaluating the differences between the registered successive images to obtain a measure of the efficacy of the therapeutic agent.  
     
     
         20 . The method of  claim 19  wherein the therapeutic agent is designed to treat rheumatic diseases affecting cartilage.  
     
     
         21 . The method of  claim 18  wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of evaluating the differences between the registered successive images to determine how to treat individual ones of the patients.  
     
     
         22 . The method of  claim 18  wherein the step of obtaining includes performing a magnetic resonance imaging acquisition and further including the step of immobilizing the diseased joint with the joint at a predetermined flexion angle during the step of performing a magnetic resonance imaging acquisition.  
     
     
         23 . The method of  claim 18  wherein the step of obtaining successive images includes performing a magnetic resonance imaging acquisition and further including the step of completely immobilizing the diseased joint with the joint at a predetermined three-dimensional position during the step of performing a magnetic resonance imaging acquisition.  
     
     
         24 . The method of  claim 23  wherein the step of immobilizing is operative to repeatedly immobilize the joint at predetermined three-dimensional positions that fall within a range of less than 7 millimeters along the longitudinal axis of the magnetic resonance imaging system used to perform the magnetic resonance imaging acquisition.  
     
     
         25 . The method of  claim 23  wherein the step of immobilizing is operative to repeatedly immobilize the joint at predetermined three-dimensional positions that fall within a range of less than 17 millimeters along the longitudinal axis of the magnetic resonance imaging system used to perform the magnetic resonance imaging acquisition.  
     
     
         26 . The method of  claim 18  wherein the step of obtaining includes performing a magnetic resonance imaging acquisition, and further includes the step of positioning one or more markers proximate the joint during the magnetic resonance imaging, and wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of evaluating image distortion for the joint based on acquired image data for the markers.  
     
     
         27 . The method of  claim 18  wherein the step of obtaining includes performing a magnetic resonance imaging acquisition, further including the step of positioning one or more markers proximate the joint during the magnetic resonance imaging, and wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of evaluating patient movement artifact for the joint based on acquired image data for the marker.  
     
     
         28 . The method of  claim 27  wherein the step of positioning positions a pair of cylinders in orthogonal locations proximate the joint.  
     
     
         29 . The method of  claim 18  wherein the step of obtaining a processed data set is operative to detect differences between information represented by the data sets within one or more sub-regions of a surface of the joint.  
     
     
         30 . The method of  claim 29  wherein the sub-regions are based on polar coordinates.  
     
     
         31 . The method of  claim 30  wherein the sub-regions are based on Cartesian coordinates.  
     
     
         32 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient, and    obtaining a processed data set expressing results of segmenting a boundary between two anatomical features of the joint based on the first magnetic resonance imaging data set,    obtaining a second magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of the same joint for the same patient, and    obtaining a processed data set expressing results of segmenting the boundary between the same two anatomical features of the same joint of the same patient based on both the second magnetic resonance imaging data set and segmentation information saved in a step of saving.    
     
     
         33 . The magnetic resonance imaging method of  claim 32  wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of administering a therapeutic agent for the disease to a plurality of patients, wherein the steps of obtaining, the steps of segmenting, and the step of saving are performed for a plurality of patients, and further including the step of evaluating the effect of the therapeutic on the disease based on results of the steps of obtaining, the steps of segmenting, and the step of saving.  
     
     
         34 . An orthopedic magnetic resonance imaging system, comprising: 
 means for obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient and for obtaining a second magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of the same joint for the same patient,    processed data means expressing results of the operation of means for segmenting a boundary between two anatomical features of the joint based on the first magnetic resonance imaging data set, of means for saving segmentation information derived by the means for segmenting, and of means for segmenting the boundary between the same two anatomical features of the same joint of the same patient based on both the second magnetic resonance imaging data set and the segmentation information saved by the means for saving.    
     
     
         35 . A magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data resulting from magnetic resonance imaging acquisition from an imaging volume for a patient,    a processed data set expressing results of the operation of a fitting module operative to fit a biparametric surface to an anatomical feature described by the data for the patient, and a projection module responsive to the magnetic resonance imaging data source and operative to project at least a portion of the data representing the three-dimensional anatomical feature onto the biparametric surface.    
     
     
         36 . The apparatus of  claim 35  wherein the surface is a biparametric surface having a three-dimensional topology.  
     
     
         37 . The apparatus of  claim 36  further including a display module responsive to the projection module to display the two dimensional surface on a planar display.  
     
     
         38 . The apparatus of  claim 36  wherein the anatomical feature includes at least the condyles of the femur and wherein the surface is a cylinder.  
     
     
         39 . The apparatus of  claim 36  wherein the anatomical feature includes at least the plateau regions of the tibia and wherein the surface is a plane.  
     
     
         40 . The apparatus of  claim 36  wherein the anatomical feature includes at least the posterior surface of the patella and wherein the surface is a plane.  
     
     
         41 . The apparatus of  claim 35  wherein the processed data set further expresses results of the operation of means for performing image manipulations on data representing the two dimensional surface.  
     
     
         42 . The apparatus of  claim 35  wherein the processed data means further expresses results of the operation of a repositioning module operative to user input to project the three-dimensional anatomical feature onto further biparametric surface layers proximate the biparametric surface.  
     
     
         43 . The apparatus of  claim 35  wherein the processed data means further expresses results of an inter-patient comparison module responsive to the projection module to compare results derived from the projections from the projection module for a plurality of different patients.  
     
     
         44 . The apparatus of  claim 43  further including a display module responsive to the inter-patient comparison module to display comparison information for the projections.  
     
     
         45 . A magnetic resonance imaging method, comprising: 
 obtaining a magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition from an imaging volume for a patient,    obtaining a processed data set expressing results of fitting a biparametric surface to an anatomical feature described by the data set for the patient, and of projecting at least a portion of the data representing the three-dimensional anatomical feature onto the biparametric surface.    
     
     
         46 . The method of  claim 45  wherein the step of obtaining a processed data set is operative to obtain a processed data set that further expresses results of repeating the steps of obtaining, fitting, and projecting for a plurality of different patients, and of comparing resulting projections for the plurality of different patients.  
     
     
         47 . A magnetic resonance imaging system, comprising: 
 means for obtaining a magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition from an imaging volume for a patient,    processed data means expressing results of the operation of means for fitting a biparametric surface to an anatomical feature described by the data set for the patient, and of means for projecting at least a portion of the data representing the three-dimensional anatomical feature onto the biparametric surface.    
     
     
         48 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of three-dimensional magnetic resonance imaging data sets resulting from magnetic resonance imaging acquisition from a joint of a patient,    a processed data set expressing results of a segmentation module that is responsive to the source of magnetic resonance imaging data sets and is operative to detect a boundary between two anatomical features of the joint in three dimensions based on three-dimensional information from a first of the data sets, and a comparison module responsive to the segmentation module and to a second of the data sets and operative to compare boundary surface data resulting from segmentation by the segmentation module for the first data set with volumetric data from the second data set.    
     
     
         49 . The apparatus of  claim 48  wherein the comparison module is included in a second segmentation module operative to segment the same boundary between the same anatomical features in the second data set.  
     
     
         50 . The apparatus of  claim 48  wherein the comparison module is included in a registration module operative to spatially register the boundary between the anatomical features segmented in the first data set with the second data set.  
     
     
         51 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first three-dimensional magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition from a joint of a patient,    obtaining a processed data set expressing results of segmenting a boundary between two anatomical features of the joint of the patient based on the first magnetic resonance imaging data set, of obtaining a second three-dimensional magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of an imaging volume for the same joint of the same patient, and of comparing surface data resulting from the step of segmenting with volumetric data resulting from the second data set.    
     
     
         52 . The method of  claim 51  wherein the comparing is part of a step of segmenting the same boundary between two anatomical features of the patient based on the second magnetic resonance imaging data set.  
     
     
         53 . The method of  claim 51  wherein the comparing is part of a second step of spatially registering the boundary between the anatomical features segmented in the first data set with the second data set.  
     
     
         54 . An orthopedic magnetic resonance imaging system, comprising: 
 means for obtaining a first three-dimensional magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition from a joint of a patient,    processed data means expressing results of the operation of means for segmenting a boundary between two anatomical features of the joint of the patient based on the first magnetic resonance imaging data set, of means for obtaining a second three-dimensional magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition from the same joint of the same patient, and of means for comparing surface data resulting from the step of segmenting with volumetric data resulting from the second data set.    
     
     
         55 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data sets resulting from successive magnetic resonance imaging acquisitions from a diseased joint of a patient, wherein the source of magnetic resonance imaging data sets includes a magnetic resonance imaging system and a support assembly operative to immobilize the diseased joint within the magnetic resonance imaging system with the joint at a predetermined three-dimensional position, and    a processed data set expressing results of the operation of a segmentation module responsive to the source of magnetic resonance imaging data sets and operative to segment surfaces in the joint based on information contained within at least one of the data sets, of a registration module responsive to the source of magnetic resonance imaging data sets and operative to spatially register, in three dimensions, information represented by a first of the data sets with respect to information represented by one or more further data sets for the same patient, and of a comparison module responsive to the registration module and operative to detect differences between information represented by the data sets caused by progression of the disease in the joint of the patient between acquisitions.    
     
     
         56 . The apparatus of  claim 55  wherein the magnetic resonance imaging system includes a knee coil and wherein the support assembly includes a heel constraint and at least two flexible wedges that are each operative to interact with a leg of the patient and the knee coil.  
     
     
         57 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data resulting from magnetic resonance imaging acquisitions from a joint of a patient,    a processed data set expressing results from a segmentation module that is responsive to the source of magnetic resonance imaging data and to segmentation result storage, and that is operative to detect a boundary between two anatomical features of the joint in three dimensions based on both three-dimensional information from the joint of the patient and prior segmentation results stored in the segmentation result storage.    
     
     
         58 . The apparatus of  claim 57  wherein the processed data set further expresses results of a registration module responsive to the source of magnetic resonance imaging data and operative to spatially register three-dimensional image data from a first acquisition for the patient and three-dimensional image data from a later acquisition for the same patient.  
     
     
         59 . An orthopedic magnetic resonance imaging system, comprising: 
 a source of magnetic resonance imaging data resulting from magnetic resonance imaging acquisitions from a diseased joint of a patient, and    a processed data set expressing results from a segmentation module that is responsive to the source of magnetic resonance imaging data sets and is operative to detect a boundary between two anatomical features of the joint in three dimensions by detecting an outline in each of a plurality of at least generally parallel planes within the volume, wherein the outline in at least some of the planes is based on data from at least one other of the planes.    
     
     
         60 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient, and    obtaining an outline of a boundary between two anatomical features of the joint of the patient in three dimensions, which results from detecting an outline in each of a plurality of at least generally parallel planes within the volume, wherein the outline in at least some of the planes is based on data from at least one other of the planes.    
     
     
         61 . The method of  claim 60  wherein the steps of obtaining are applied to a medical patient.  
     
     
         62 . The method of  claim 60  wherein the steps of obtaining are applied to a veterinary patient.  
     
     
         63 . An orthopedic magnetic resonance imaging system, comprising: 
 means for obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient, and    processed data means expressing results of segmenting an outline of a boundary between two anatomical features of the joint of the patient in three dimensions by detecting an outline in each of a plurality of at least generally parallel planes within the volume, wherein the outline in at least some of the planes is based on data from at least one other of the planes.    
     
     
         64 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient,    obtaining a processed data set expressing results of delineating joint features in the first magnetic resonance imaging data set, of obtaining a second magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of the same joint for the same patient after the step of obtaining a first magnetic resonance imaging data set, of delineating joint features in the second magnetic resonance imaging data set, spatially registering joint features delineated in the first magnetic resonance imaging data set and joint features delineated in the second magnetic resonance imaging data set, and of detecting differences between the spatially registered data sets for the patient, and    evaluating the effects of one or more pharmaceutical agents on the patient based on results of the step of comparing.    
     
     
         65 . The method of claim  100  wherein the step of evaluating is applied for a pharmaceutical agent designed to treat rheumatic diseases affecting the cartilage.  
     
     
         66 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient,    obtaining a processed data set expressing results of delineating joint features in the first magnetic resonance imaging data set, of obtaining a second magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of the same joint for the same patient after the step of obtaining a first magnetic resonance imaging data set, of delineating joint features in the second magnetic resonance imaging data set, of spatially registering joint features delineated in the first magnetic resonance imaging data set and joint features delineated in the second magnetic resonance imaging data set, and of detecting differences between the spatially registered data sets for the patient, and    determining how to treat the patient based on results of the step of comparing.    
     
     
         67 . A method of monitoring disease progression in a joint, comprising: 
 obtaining a first magnetic resonance imaging data set resulting from magnetic resonance imaging acquisition of a joint of a patient,    obtaining a processed data set expressing results of delineating joint features in the first magnetic resonance imaging data set, of obtaining a second magnetic resonance imaging data set resulting from a magnetic resonance imaging acquisition of the same joint for the same patient after the step of obtaining a first magnetic resonance imaging data set, of delineating joint features in the second magnetic resonance imaging data set, of spatially registering joint features delineated in the first magnetic resonance imaging data set and joint features delineated in the second magnetic resonance imaging data set, and of detecting differences between the spatially registered data sets for the patient, and    administering treatment delivery for the patient based on results of the step of comparing.    
     
     
         68 . The method of  claim 67  wherein the step of obtaining a first magnetic resonance imaging data set obtains a baseline magnetic resonance imaging data set.