Michael Kiefer1, Regina Eymann. 1. Department of Neurosurgery, Saarland University Medical School, Homburg-Saar, Germany. Michael.Kiefer@uks.eu
Abstract
INTRODUCTION: Recently decreased compliance is discussed as an initially disturbed CSF hydrodynamic parameter in hydrocephalus. MATERIALS AND METHODS: In 180 patients with suspected chronic hydrocephalus we performed a dynamic infusion test, which was not used for shunt indication. Shunt indication was based on long-term ICP monitoring. Follow-up was 4.6 +/- 1.8 years. STATISTICS: Spearman-, Kruskal-Wallis-, Wilcoxen-U-test. RESULTS: Resistance to outflow (Rout) and Pressure Volume Index (PVI) alone provide positive predictive values (PPV) and sensitivity, which might be sufficient in daily practice, while negative predictive values (NPV) and specificity are weak. With an intelligent combined algorithm of Rout and PVI at a critical value of ROF of 13 mm Hg/ml x min and 30 ml, a clearly improved outcome prediction is possible. CONCLUSION: These clinical results support recent opinions concerning the meaning of Compliance and Rout in hydrocephalus patho-physiology.
INTRODUCTION: Recently decreased compliance is discussed as an initially disturbed CSF hydrodynamic parameter in hydrocephalus. MATERIALS AND METHODS: In 180 patients with suspected chronic hydrocephalus we performed a dynamic infusion test, which was not used for shunt indication. Shunt indication was based on long-term ICP monitoring. Follow-up was 4.6 +/- 1.8 years. STATISTICS: Spearman-, Kruskal-Wallis-, Wilcoxen-U-test. RESULTS: Resistance to outflow (Rout) and Pressure Volume Index (PVI) alone provide positive predictive values (PPV) and sensitivity, which might be sufficient in daily practice, while negative predictive values (NPV) and specificity are weak. With an intelligent combined algorithm of Rout and PVI at a critical value of ROF of 13 mm Hg/ml x min and 30 ml, a clearly improved outcome prediction is possible. CONCLUSION: These clinical results support recent opinions concerning the meaning of Compliance and Rout in hydrocephalus patho-physiology.