Method and apparatus for determining characteristics of cerebral ischemia based on magnetic resonance diffusion weighted imaging

An apparatus for determining characteristics of cerebral ischemia based on magnetic resonance diffusion weighted imaging, wherein the apparatus comprises:

• a cerebral ischemia region determining module, configured to determine a cerebral ischemia region of a patient based on magnetic resonance diffusion weighted imaging of the patient, wherein the cerebral ischemia region comprises a core region and a transition region;
• a gray scale distribution parameter determining module, configured to determine a diffusion weighted image DWI gray scale distribution parameter in a region with low ADC values in the magnetic resonance diffusion weighted imaging according to the apparent diffusion coefficient ADC values of the core region and transition region, wherein the DWI gray scale distribution parameter comprises a mean square error DWIsd of the DWI in the region with low ADC values in the magnetic resonance diffusion weighted imaging, wherein the DWIsd is configured to judge an uneven distribution of gray level of the DWI;
• and
• a statistics collecting unit, configured to obtain a value STP(STP+SFN) indicative of sensitivity and a value STN/(SFP+STN) indicative of specificity by performing statistics, among the N patients, on a sum STP of patients who have bad prognosis after thrombolysis and who have good prognosis without thrombolysis when DWIsd is greater than or equal to a threshold Thresh1 to be determined, a sum STN of patients who have good prognosis after thrombolysis and who have bad prognosis without thrombolysis when DWIsd is less than the threshold Thresh1 to be determined, a sum SFP of patients who have good prognosis after thrombolysis and who have bad prognosis without thrombolysis when DWIsd is greater than or equal to the threshold Thresh1 to be determined, and a sum SFN of patients who have bad prognosis after thrombolysis and who have good prognosis without thrombolysis when DWIsd is less than the threshold Thresh1 to be determined;
• and
• an obtaining unit, configured to calculate a values of the threshold Thresh1 to be determined that makes STP/(STP+SFN)+(SFP+STN) reach a maximum value, and use the value of the threshold Thresh1 to be determined that makes STP(STP+SFN)+STN/SFP+STN) reach the maximum value as the threshold ThreshDWI which is used to judge whether the DWI in the region with low ADC values in the magnetic resonance diffusion weighted imaging and the ADC values in the region with low ADC values in the magnetic resonance diffusion weighted imaging are mismatched;
• wherein N is a natural number greater than 1;
• and
• a first judging submodule, configured to judge, if the mean square error DWIsd of the DWI in the region with low ADC values in the magnetic resonance diffusion weighted imaging is not less than the threshold ThreshDWI, that the DWI in the region with low ADC values in the magnetic resonance diffusion weighted imaging and the ADC values in the region with low ADC values in the magnetic resonance diffusion weighted imaging are mismatched, if mismatched, then the patient is not treated with thrombolysis;
• if matched, the patient is treated with thrombolysis.