The Effect of Dexamethasone and Diuretics on Peritumor Brain Edema: Comparative Study of Tissue Water Content and CT

Eighteen brain tumor patients were pre-operatively treated with dexamethasone, 4 × 4 mg i.m. for 4–6 days, and furosemide, 3 × 40 mg p.o. for 2–4 days. Water and electrolyte content were determined in biopsies removed from peritumoral cortex and white matter during operation and compared with the results from 31 patients not pre-treated and 28 patients treated with dexamethasone alone (16–24 mg i.m./day for 4–6 days). While the water content in cortex did not change significantly it fell in white matter from 79.90 ± 0.81 in untreated to 77.29 ± 0.76 in dexamethasone-treated and to 75.53 ± 1.03 in patients treated with a combination of dexamethasone and furosemide. With the diminution of water content, sodium and chloride contents also decreased. By computerized axial tomography (CT) it is possible to visualize the dynamic process of formation and resolution of peritumor brain edema. Following combined therapy, and substantially less, following dexamethasone therapy, a diminution of the peritumor edematous area was demonstrated, along with a reduction of the shift of midline structures (dislocation of septum pellucidum, pineal body, third ventricle, etc.), reopening of compressed ventricles and of cisterns, as well as regression of displaced ventricles.