Increased nationwide use of stereoencephalography for intracranial epilepsy electroencephalography recordings

Abstract

Intracranial electroencephalography (iEEG) can be performed using minimally invasive stereo-electroencephalography (SEEG) or by implanting subdural electrodes via a craniotomy or multiple burr holes. There is anecdotal evidence that SEEG is becoming more common in the United States, though this has yet to be quantified. To address this question, all SEEG and burr hole/craniotomy subdural iEEG procedures were extracted from the Centers for Medicare and Medicaid Services Part B data files for the years 2000-2016. National trends were compared over time. In 2016, SEEG became the most frequently performed intracranial monitoring procedure in the Medicare population, increasing from 28.8% of total cases in 2000 to 43.1% in 2016 (p = 0.02). The proportion of strip electrode cases (through burr holes) significantly declined, while the frequency of craniotomies for subdural grid placement did not significantly change. These data are consistent with a nationwide increase in the utilization of SEEG with a concomitant decline in burr hole placement of subdural strip electrodes in the United States. The factors driving these changes are unknown, but are likely due in part to the desire for minimally invasive surgical options.

Keywords: Depth electrodes; Electrode array; Epilepsy; Intracranial electroencephalography; Stereoencephalography; Strip electrodes.

Fig. 1.

Trends in iEEG recordings techniques in the United States using national data from CMS. The top panel shows the number of cases per year and the middle panel shows the frequency of cases per year, both demonstrating that SEEG cases significantly increased from 2000 to 2016, while subdural implantation of only strip electrodes through burr holes declined and craniotomy with subdural implantation of electrode arrays, grids, strips, and/or depth electrodes remained stable. The pie charts depict the proportions of iEEG recordings techniques for the first and last year of the study (2000 and 2016).