Table 2.
Human studies comparing frequency measurements of slow wave CBF and CSF oscillations using MRI imaging (upper) vs. analysis of TCD derived CBF, and ICP pressure measured oscillations (lower) cpm, cycles per min; Hz, cycles per sec.
| Author Method | CBF frequency range | CBF frequency peak mean | CSF | EEG |
|---|---|---|---|---|
| Horowitz et al. (8) MRI Bold (sleep) | 0.01–0.03 Hz, 0.6–1.8 cpm | 0.02–0.03 Hz 1.2–1.8 cpm |
No | Yes |
| Fukunaga et al. (7) MRI Bold (sleep) | 0.01–0.05 Hz 0.6–3 cpm | No | Yes | |
| Raichle and Snyder (9) MRI Bold (resting) |
Not given | Approx 2–3 cpm | No | No |
| Fultz et al. (2) MRI Bold and CSF (sleep) |
Not given | d/dt max=0.05 Hz or “about” 3 cpm | 0.05 Hz or 3 cpm in 4th ventricle (peak) | Yes |
| Kiviniemi et al. (4) MRI Bold, (anesthesia) |
0.025–0.041 Hz 1.5–2.5 cpm |
0.033 Hz 2.0 cpm |
No | |
| Kiviniemi et al. (6) MRI Bold (sedation) | 0.02–0.06 Hz 1.2–3.6 cpm |
No | ||
| Kiviniemi et al. (5) MRI CSF pulsations in brain parenchyma |
Total range LF= low frequency VLF= very low frequency |
1.6–4.4 (cpm) 0.01–0.073 Hz 1.6–4.4 (cpm) 0.027–0.073 Hz 0.61 = 1.6 (cpm) 0.01–0.027 Hz | ||
| Current findings TCD and ICP (head injury) | 0.011–0.038 Hz 0.6–2.3 cpm | Mean= 0.0245 Hz, 1.5 cpm | ICP monitoring | No |
| Spiegelberg et al. (18) TCD and ICP (review) | 0.0055–0.05 Hz 0.33–3 cpm | ICP monitoring | No | |
| Martinez-Tejada, et al. (19) TCD and ICP (review) | 0.003–0.067 Hz 0.2-4 cpm | ICP monitoring | No |