EVIDENCE OF OPTIC PATHWAY GLIOMAS AFTER PREVIOUSLY NEGATIVE NEUROIMAGING

Purpose: The authors emphasize the potential far the development of an terior visual pathway gliomas, evidenced by computed tomography (CT) o r magnetic resonance imaging (MRI) scans, in neurofibromatosis type 1 (NF1) patients who previously had normal neuroimaging studies. Methods : The clinic charts and CT and MRI scans were retrospectively reviewed for all patients evaluated al the neurofibromatosis clinic of one ref erral center over a period of 7 years. Patients with neuroimaging stud ies demonstrating anterior visual pathway gliomas who previously had n ormal scans were identified, and their cases are described in detail. A similar, previously reported series, from the pediatric literature, was also reviewed, Results: Eight percent (28/360) of patients had CT or MRI scans revealing optic gliomas. Two of these patients had normal neuroimaging studies previously, Conclusion: A negative neuroimaging study in an NF1 patient does not exclude the future development of an optic glioma.