Neurosurgical implications of mannitol accumulation within a meningioma and its peritumoral region demonstrated by magnetic resonance spectroscopy

Case report

Restricted access

✓Mannitol is widely considered the hyperosmolar therapy of choice in routine neurosurgical practice for the reduction of intracranial pressure (ICP). The authors present a unique case of a patient with a large meningioma treated with mannitol, in which mannitol accumulation within the tumor and its surrounding parenchyma was shown using in vivo magnetic resonance spectroscopy (MRS). This rare appearance of mannitol on MRS was characterized by a wide-based peak at 3.8 ppm, which remained detectable several hours after the last dose. These findings provide the first in vivo evidence in support of the prevailing theory that mannitol leakage into the peritumoral edematous region may contribute to rebound increases in ICP and suggest that this phenomenon has the potential to occur in extraaxial tumors. Judicious use of mannitol in the setting of elevated ICP due to tumor may be indicated to avoid potentially deleterious side effects caused by its accumulation.

Abbreviations used in this paper: BBB = blood–brain barrier; CT = computed tomography; ICP = intracranial pressure; MR = magnetic resonance; MRS = MR spectroscopy.

Article Information

Address correspondence to: Mark C. Preul, M.D., Neurosurgery Research Laboratory, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, 350 West Thomas Road, Phoenix, Arizona 85013. email:

© AANS, except where prohibited by US copyright law.



  • View in gallery

    Preoperative MR image (A) and intratumoral single-voxel spectroscopy results of the MRS procedure (B and C). A: Axial T1-weighted image after intravenous contrast administration shows a large, extraaxial, uniformly enhancing left frontal tumor causing significant mass effect, midline shift, and significant compression of both lateral ventricles. Pathological assessment confirmed the tumor to be a World Health Organization Grade I meningothelial/transitional meningioma. The area delimited by the square marked “1” represents the intratumoral voxel selected for analysis using single-voxel MRS. B: Graph showing spectroscopy results obtained at TE = 35 msec. Note the prominent mannitol peak at 3.8 ppm and the large choline (Cho) peak at 3.2 ppm. The absence of a creatine peak at 3.0 ppm and the broad-based glutamate/glutamine (Glx) peak at 2.0–2.5 ppm is characteristic of a meningioma. C: Graph showing spectroscopy results obtained at TE = 144 msec. The mannitol peak is still clearly noted at 3.8 ppm. The inverted alanine doublet at 1.4 ppm is nearly pathognomonic of a meningioma. Ala = alanine.

  • View in gallery

    Preoperative MR image overlayed with a volume-of-interest grid (A) and corresponding spectrum close-ups from specific voxels (B and C). A: Axial T1-weighted image after intravenous contrast administration and overlaid volume-of-interest grid covering the tumor and the peritumoral area shows voxels (1–15) that were analyzed using multivoxel chemical-shift imaging at TE = 144 msec. B: Close-up of spectrum in voxel 9, from within the tumor. Note the presence of a large mannitol peak at 3.8 ppm, confirming mannitol accumulation within the tumor. The peak at 3.2 ppm represents choline, and the inverted peak for alanine at 1.4 ppm is characteristic of meningiomas. C: Close-up of spectrum from voxel 1, from the peritumoral area. A mannitol peak at 3.8 ppm is present, demonstrating that mannitol accumulation has also occurred in the peritumoral brain tissue. The peak at 3.2 ppm represents choline, whereas an N-acetyl aspartate (NAA) peak, indicating the presence of neurons, is found at 2.0 ppm, confirming that the voxel is situated within the brain parenchyma.


  • 1

    Bitzer MNagele TGeist-Barth BKlose UGronewaller EMorgalla M: Role of hydrodynamic processes in the pathogenesis of peritumoral brain edema in meningiomas. J Neurosurg 93:5946042000

  • 2

    Bullock RChestnut RMClifton GGhajar JMarion DWNarayan RK: Guidelines for the management of severe head injury. Brain Trauma Foundation. Eur J Emerg Med 3:1091271996

  • 3

    Cianfoni ACha SBradley WGDillon WPWintermark M: Quantitative measurement of blood-brain barrier permeability using perfusion-CT in extra-axial brain tumors. J Neuroradiol 33:1641682006

  • 4

    Danielsen ERRoss B: Magnetic Resonance Spectroscopy Diagnosis of Neurological Diseases New YorkMarcel Dekker1999. 3031300301

  • 5

    Essig MWeber MAvon Tengg-Kobligk HKnopp MVYuh WTCGiesel FL: Contrast-enhanced magnetic resonance imaging of central nervous system tumors. Agents, mechanisms, and applications. Top Magn Reson Imaging 17:891062006

  • 6

    Hartwell RCSutton LN: Mannitol, intracranial pressure, and vasogenic edema. Neurosurgery 32:4444501993

  • 7

    Holodny AINusbaum AOFesta SPronin INLee HJKalnin AJ: Correlation between the degree of contrast enhancement and the volume of peritumoral edema in meningiomas and malignant gliomas. Neuroradiology 41:8208251999

  • 8

    Ito UTomita HTone OMasaoka HTominaga B: Peritumoral edema in meningioma: a contrast enhanced CT study. Acta Neurochir Suppl (Wien) 60:3613641994

  • 9

    Javid MGilboe DCesario T: The rebound phenomenon and hypertonic solutions. J Neurosurg 21:105910661964

  • 10

    Kaal ECVecht CJ: The management of brain edema in brain tumors. Curr Opin Oncol 16:5936002004

  • 11

    Kaufmann AMCardoso ER: Aggravation of vasogenic cerebral edema by multiple-dose mannitol. J Neurosurg 77:5845891992

  • 12

    Kofke WA: Mannitol: potential for rebound intracranial hypertension?. J Neurosurg Anesthesiol 5:131993

  • 13

    Law M: MR spectroscopy of brain tumors. Top Magn Reson Imaging 15:2913132004

  • 14

    Maioriello AVChaljub GNauta HJWLacroix M: Chemical shift imaging of mannitol in acute cerebral ischemia. J Neurosurg 97:6876912002

  • 15

    McManus MLSoriano SG: Rebound swelling of astroglial cells exposed to hypertonic mannitol. Anesthesiology 88:158615911998

  • 16

    Paczynski RP: Osmotherapy: basic concepts and controversies. Crit Care Clin 13:1051291997

  • 17

    Palma LBruni GFiaschi AIMariottini A: Passage of mannitol into the brain around gliomas: a potential cause of rebound phenomenon. A study on 21 patients. J Neurosurg Sci 50:63662006

  • 18

    Peeling JSutherland G: High-resolution 1H NMR spectroscopy studies of extracts of human cerebral neoplasms. Magn Reson Med 24:1231361992

  • 19

    Zhu XPLi KLKamaly-Asl IDCheckley DRTessier JJWaterton JC: Quantification of endothelial permeability, leakage space, and blood volume in brain tumors using combined T1 and T2* contrast-enhanced dynamic MR imaging. J Magn Reson Imaging 11:5755852000




All Time Past Year Past 30 Days
Abstract Views 126 126 31
Full Text Views 138 138 2
PDF Downloads 290 290 1
EPUB Downloads 0 0 0


Google Scholar