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Accelerated methaemoglobin formation: potential pitfall in early postoperative MRI.

U Meyding-Lamadé·M Forsting·F Albert·S Kunze·K Sartor
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Abstract

Postoperative magnetic resonance imaging (MRI) of glioblastomas to assess residual tumour should be performed within the first 4 days following surgery. Early methaemoglobin formation near the resection site may mimic residual tumour if only gadolinium-DTPA-enhanced images are obtained. In a prospective study 24 of 54 patients (44%) showed well-defined areas of increased signal intensity on unenhanced T1-weighted images performed soon after surgery. By in vitro experiments we showed that hydrogen peroxide used in neurosurgery as a styptic agent accelerates formation of methaemoglobin when added to whole blood samples.

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BrainBrain NeoplasmsContrast MediaDiagnosis, DifferentialFemaleGadoliniumGadolinium DTPAGlioblastomaHemoglobinsHemostaticsHumansHydrogen PeroxideImage EnhancementMagnetic Resonance ImagingMaleMethemoglobinMiddle AgedOrganometallic CompoundsOxidation-ReductionPentetic AcidPostoperative CareProspective StudiesTime FactorsTomography, X-Ray ComputedJournal Article

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U Meyding-Lamadé, M Forsting, F Albert, S Kunze, K Sartor. 1993. Accelerated methaemoglobin formation: potential pitfall in early postoperative MRI.. https://doi.org/10.1007/bf00588487

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