# Deep Brain Stimulation Lead Functional Repositioning After Spontaneous Pneumocephalus Resorption: A Clinical Case Presentation and Systematic Review

## TL;DR

A Parkinson's patient experienced electrode displacement after DBS surgery, but the electrodes spontaneously repositioned as air in the brain resolved, avoiding reoperation.

## Contribution

This case and review highlight the rare occurrence of spontaneous electrode repositioning after pneumocephalus in DBS patients.

## Key findings

- Electrode displacement occurred in 75% of cases, but only 12.5% showed spontaneous repositioning.
- Spontaneous repositioning was more common with air volumes below 10 cm³.
- Larger air volumes often required surgical intervention, but clear thresholds for action remain undefined.

## Abstract

Deep brain stimulation (DBS) has become a critical intervention for managing advanced Parkinson's disease (PD), particularly for patients whose symptoms are no longer controlled by medication. This report details the case of a 61-year-old male with PD who experienced electrode displacement due to pneumocephalus following DBS surgery targeting the subthalamic nucleus (STN). Initial imaging revealed a significant subdural air volume causing electrode displacement. However, one month later, spontaneous pneumocephalus resorption led to the functional repositioning of the electrodes, restoring proper function and negating the need for reoperation. The accompanying systematic review analyzed 24 studies, involving 1,439 patients across 12 countries, to assess the occurrence and management in this specific scenario. Findings showed electrode displacement occurred in 75% of cases, but spontaneous repositioning happened only in 12.5%, typically with air volumes below 10 cm³. Larger volumes often required surgical intervention, though definitive thresholds for action remain unclear. The review highlights inconsistencies in managing this complication, emphasizing the need for clearer protocols to improve outcomes. This work underscores the rarity of spontaneous electrode realignment and the importance of careful evaluation of pneumocephalus volume and patient symptoms. It advocates for evidence-based management strategies to balance clinical intervention with the potential for natural resolution, aiming to enhance DBS efficacy and patient quality of life. Further research is necessary to establish standardized guidelines for addressing this complication.