Dynamic changes of cerebrospinal fluid shunt flow in patient's daily life.

The shunt flow rate will be greatly influenced by the changing posture of the patient. A newly designed method of assessing shunt flow rate by isotope clearance is described and the results of phantom experiments and clinical data are presented. This method makes it possible to assess shunt flow rates in a variety of postures, such as recumbent, or head raised or as posture changes from recumbent to sitting and eventually to upright. As patients changed from the recumbent to the sitting position, shunt flow rates ceased in some cases. In cases with low flow rates in the recumbent position, shunt flow rate increased with any elevation of the upper half of the body. In many cases, flow rates increased as the patient's position changed from recumbent to sitting and then to the upright position. The results suggest that shunt flow rates vary substantially as postures alter in a patient's daily life.