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False-negative computerized tomography in brain tumor.

COMPUTERIZED axial tomography (CT) has been used in clinical neuroradiology for slightly less than four years and is considered to be the most effective means for diagnosing brain tumors. Diagnosis by CT of cerebral infarction, 1 cerebral and intraventricular hemorrhage, 2 and brain tumors 3 has been reported. Refinements of technique, especially the intravenous injection of iodinated contrast material, 4 have led to increased yields in tumor diagnosis. Tumors are being discovered at a rate not achieved with isotope scanning 5 and at a rate equal to arteriography without its concomitant risk. Such successes, however, may lead to an unwarranted assumption that a tumor does not exist if it does not visualize on CT scan. We report a case of false-negative CT scan in a patient who had a brain tumor. Report of a Case A 52-year-old, right-handed woman was seen for the first time on Sept 3, 1976. On