Table 1.
Comparison of UTE and IR-UTE results obtained with half excitation pulses in three cerebral hemisphere slabs before and after these specimens were subjecte to 27-hr 4-pass D2O exchange.
| Native | Deuterated | |||||
|---|---|---|---|---|---|---|
|
| ||||||
| UTE | IR-UTE (TI = 295 ms) |
IR-UTE (TI = 365 ms) |
UTE |
IR-UTE (TI = 250 ms) |
IR-UTE (TI = 380 ms) |
|
| T2S* | ||||||
|
| ||||||
| No. 1 | n.a. | 339 ± 34 µs | 210 ± 69 µs | 239 ± 46 µs | 297 ± 21 µs | 229 ± 39 µs |
| No. 2 | n.a. | 246 ± 28 µs | 202 ± 22 µs | 241 ± 48 µs | 245 ± 10 µs | 262 ± 35 µs |
| No. 3 | n.a. | 215 ± 50 µs | 205 ± 64 µs | 215 ± 50 µs | 247 ± 21 µs | 262 ± 42 µs |
|
| ||||||
| fS | ||||||
|
| ||||||
| No. 1 | n.a. | ≈100%# | 18.0 ± 2.1 % | 42.4 ± 0.4 % | ≈100%# | ≈100%# |
| No. 2 | n.a. | ≈100%# | 17.5 ± 1.7 % | 43.1 ± 2.2 % | ≈100%# | ≈100%# |
| No. 3 | n.a. | ≈100%# | 16.0 ± 1.7 % | 39.1 ± 1.3 % | ≈100%# | ≈100%# |
n.a., signals on the UTE images showed single component decay with long T2* (22 ± 2 ms); #, signals on the IR-UTE images showed single component decay with oultrashort T2*.