A 55-year-old woman had progressive gait unsteadiness, vertigo, and intermittent diplopia for 1.5 years. Clinical examination revealed multidirectional gaze-evoked nystagmus, bilateral Babinski sign, and gait and (left-predominant) limb ataxia. Brain magnetic resonance imaging (Figure 1) showed a diffuse brain stem and cerebellar infiltrative process without gadolinium enhancement on T1-weighted imaging. In contrast to early fludeoxyglucose F 18 positron emission tomographic images, late images revealed brainstem hypermetabolism, most prominent in the mesencephalon (Figure 2). Stereotactic biopsy of the left middle cerebellar peduncle revealed a glioma (World Health Organization grade 2). A diagnosis of diffuse low-grade brain stem glioma was made and temozolomide chemotherapy was started.
Renard D, Le Floch A, Collombier L, De Verdal M, Campello C, Labauge P. Diffuse Brain Stem Glioma. Arch Neurol. 2010;67(3):368-369. doi:10.1001/archneurol.2010.12