[Optic neuropathy and meningioma: a diagnostic trap].

INTRODUCTION

Meningiomas are benign primary meningeal tumors. Their diagnosis may be incidental or in response to a work-up for neurological or ophthalmological symptoms.

PATIENTS AND METHODS

The clinical course of five patients with ophthalmological symptoms leading to the diagnosis of meningioma is described.

RESULTS

The case reports consist of five women (48 to 54 years old - mean 52 years at the onset of symptoms), all suffering from a progressive unilateral decrease in visual acuity with a normal initial fundus examination and ipsilateral visual field changes. Ancillary testing, in particular MRI and CT-scans, had to be repeated to make the diagnosis of meningioma, which was delayed from 18 months to 4 years.

DISCUSSION

The clinical presentation of these five cases was that of a retrobulbar optic neuropathy, which biased the work-up towards an inflammatory disease of the central nervous system such as multiple sclerosis. However, the atypical character of the neuropathy, which did not respond to intravenous steroids, caused the diagnosis to be questioned and radiological examinations repeated. The iso-intense appearance of meningiomas on T1 MR imaging and only slightly hyperintense appearance on T2 may result in a diagnostic delay if the exam is not performed and interpreted by an experienced professional. Gadolinium contrast, fat suppression and centration on the anterior visual pathways are essential to a proper MRI examination.

CONCLUSION

When confronted with a progressive, painless optic neuropathy unresponsive to steroid treatment, the diagnosis of meningioma of the anterior visual pathways must be considered. This diagnosis is enabled by a targeted MRI of the anterior visual pathways.