Disappearance of Breach Rhythm Heralding Recurrent Tumor Progression in a Patient With Astrocytoma

Abstract

The breach rhythm is sometimes considered the consequence of reduced resistance between the cortex and the scalp electrode in the region of a skull defect. On the other hand, the electroencephalographic (EEG) changes after craniotomy were attributed to an activation of EEG activity by meningocortical adhesions with admixed gliosis. We report changes of the breach rhythm in a patient with astrocytoma, which give further evidence that the breach rhythm is not merely the result of physical changes in the area of a skull defect. In our patient, the breach rhythm was no longer detectable before a new tumor progression took place, showed up again, and at the end changed into localized slowing before the deterioration of the patient's general medical condition. This case suggests that in patients with brain tumors, the loss or attenuation in frequency of an established breach rhythm might be considered as an indication of a new tumor progression.