Table 2:
Regression-derived effects of scan duration on the volume of brain tissue with Tmax greater than 6 seconds
| Hemodynamic Measurement | Deconvolution Algorithm | t-statistic | Lesion Volume Slopea | Potential Truncation Effectb |
|---|---|---|---|---|
| sTmax | sSVD | 44.21 | 162.7 mL/log10(s) | 71.5 mL |
| oTmax | oSVD | 47.94 | 213.4 mL/log10(s) | 93.8 mL |
a
The slopes of sTmax and oTmax lesion volumes with respect to the logarithm of scan duration were both significantly greater than zero with P < .001. Therefore, t-statistics rather than P values are reported.
b
“Potential truncation effect” reflects the expected decrease in the lesion volume that would result from decreasing the scan duration from 110 seconds to 40 seconds postinjection. For example, if the volume of an oTmax lesion were measured to be 150 mL using a 110-second scan, the expected lesion volume derived from a 40-second scan would be 56.2 mL.