FIG 3. Cytotoxic effect of mannitol on five meningioma cell lines. The average kill rates of five meningioma cell lines by 300 mOsm (M300) of mannitol, 600 mOsm (M600), of mannitol and mannitol/iohexol 2:1 mixture (M/I) are shown in this graph. The cell death rates are 22 ± 2% and 23 ± 3% for 600 mOsm of mannitol and mannitol and iohexol mixture, respectively. Little cytotoxic effect is seen for normalsaline (NS) and iohexol alone (I).