title: Dynamic measurement of the flow rate in cerebrospinal fluid shunts in hydrocephalic patients.
abstract: We compared clinical outcomes in hydrocephalic patients and observed variation in the rate of flow in ventriculoperitoneal shunts with changes in posture in 231 separate examinations of shunt flow in 148 patients. A small cadmium telluride detector was placed over the shunt reservoir, and clearance of radioisotope injected into the reservoir was recorded as a measure of flow. Flow rate tended to increase during head elevation. Four patterns of radioisotope clearance were seen: type I, no flow; type II, adequate flow with moderate opening pressure; type III, adequate flow with low opening pressure; and type IV, excessive flow. This categorisation reflected clinical shunt function. Our method effectively assesses flow rate with the patient in a variety of postures or during movement, yielding useful information for adjustment of shunt valve pressure.
authors.affiliation: Department of Neurosurgery, Tokai University School of Medicine, Isehara, Kanagawa, Japan. kmhidaka@eurus.dti.ne.jp
authors.forename: M
authors.initials: M
authors.lastname: Hidaka
authors.forename: M
authors.initials: M
authors.lastname: Matsumae
authors.forename: K
authors.initials: K
authors.lastname: Ito
authors.forename: R
authors.initials: R
authors.lastname: Tsugane
authors.forename: Y
authors.initials: Y
authors.lastname: Suzuki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002555:Cerebrospinal Fluid / Q000502:physiology*; D015902:Gamma Cameras; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D008875:Middle Aged; D011187:Posture; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012212:Rheology; D013670:Sodium Pertechnetate Tc 99m; D017287:Ventriculoperitoneal Shunt / Q000295:instrumentation
chemical_list: D019275:Radiopharmaceuticals; D013670:Sodium Pertechnetate Tc 99m