Table 2:

Pre- to post-lumbar puncture changes in ICP and CSF volume differences in the various compartments, amounts of CSF withdrawn, and the calculated effective CSF production rates

	Closing-Opening Pressure (cm H₂O)	EVC CSF Vol Change (mL)	Ventricular CSF Vol Change (mL)	SC CSF Vol Change (mL)	Total CSF Vol Change (mL)	Amount of CSF Collected (mL)	Effective CSF Production Rate (mL/min)
Subject No.
1	NA	−1.6	0.0	−5.3	−6.9	−16.0	0.25
2	−26	−2.0	−0.1	−6.2	−8.2	−16.0	0.24
3	−3	−3.6	−0.1	−6.0	−9.6	−14.0	NA^{^a}
4	−15	0.7	0.2	−3.3	−2.5	−14.0	0.65
5	−16	2.0	0.1	−12.7	−10.5	−21.0	0.43
6	−20	−1.6	−0.6	−8.1	−10.3	−20.0	0.63
7	−12	−1.0	−0.2	−2.7	−3.9	−8.5	0.24
8	−28	0.8	0.1	−9.1	−8.2	−17.0	0.40
Mean	−17 ± 8.6	−0.8 ± 1.8	−0.1 ± 0.2	−6.7 ± 3.2	−7.5 ± 2.9	−15.8 ± 3.9	0.41 ± 0.18
P value	.002^{^b}	.24	.45	.0007^{^b}	.0002^{^b}

Note:—ICP indicates intracranial pressure; NA, not available; EVC, extraventricular cranial; SC, spinal canal; Vol, volume.
↵a Effective CSF production rate for subject 3 was not calculated because the lumbar puncture time was not available.
↵b Significant.