Table 3: 2 × 2 table values for ASL and DSC. The top two tables are the synchronous cohorts of ASL and DSC i.e. both DSC and ASL were performed on the patient minutes apart on the same scanner. ASL was performed as the last noncontrast sequence, the followed by DSC as the first post contrast sequence. The bottom tables are the subset of 24 synchronous studies where both ASL and DSC were performed, censored by exclusion of three patients whose outcomes remained indeterminate over the study period.

A

ASL synchronous
Cond. + Cond. - Sum PPV, NPV
Test + 5 1 6 0.83
Test - 2 19 21 0.9
Sum 7 20 27
Sens., Spec. 0.71 0.95 0.89

B

DSC synchronous
Cond. + Cond. - Sum PPV, NPV
Test + 5 1 6 0.83
Test - 3 8 21 0.86
Sum 8 20 27
Sens., Spec. 0.625 0.9 0.85

C

ASL censored
Cond. + Cond. - Sum PPV, NPV
Test + 5 0 5 1
Test - 2 17 19 0.89
Sum 7 17 24
Sens., Spec. 0.71 1 0.92

D

DSC censored
Cond. + Cond. - Sum PPV, NPV
Test + 4 0 4 1
Test - 3 17 20 0.85
Sum 7 17 24
Sens., Spec. 0.57 1 0.88