A pilot study of human brain tissue post-magnetic resonance imaging: information from the National Deep Brain Stimulation Brain Tissue Network (DBS-BTN).

INTRODUCTION: The safety of magnetic resonance imaging (MRI) for deep brain stimulation (DBS) patients is of great importance to both movement disorders clinicians and to radiologists. The present study utilized the Deep Brain Stimulation Brain Tissue Network's (DBS-BTN's) clinical and neuropathological database to search for evidence of adverse effects of MRI performed on implanted DBS patients. HYPOTHESIS: Performing a 1.5 T MRI with a head receive coil on patients with implanted DBS devices should not result in evidence of adverse clinical or pathological effects in the DBS-BTN cohort. Further, exposing post-mortem DBS-BTN brains with DBS leads to extended 3T MRI imaging should not result in pathological adverse effects. METHODS: An electronic literature search was performed to establish clinical and neuropathological criteria for evidence of MRI-related adverse reactions in DBS patients. A retrospective chart review of the DBS-BTN patients was then performed to uncover potential adverse events resulting from MRI scanning. DBS patient characteristics and MRI parameters were recorded for each patient. In addition, 3T MRI scans were performed on 4 post-mortem brains with DBS leads but without batteries attached. Detailed neuropathological studies were undertaken to search for evidence of MRI-induced adverse tissue changes. RESULTS: No clinical signs or symptoms or MRI-induced adverse effects were discovered in the DBS-BTN database, and on detailed review of neuroimaging studies. Neuropathological examination did not reveal changes consistent with MRI-induced heating damage. The novel study of four brains with prolonged 3T post-mortem magnetic field exposure (DBS leads left in place) also did not reveal pathological changes consistent with heat related damage. DISCUSSION: The current study adds important information to the data on the safety of MRI in DBS patients. Novel post-mortem MRI studies provide additional information regarding the safety of 3T MRI in DBS patients, and could justify additional studies especially post-mortem scans with battery sources in place. CONCLUSION: The lack of pathological findings in the DBS-BTN database and the lack of tissue related changes following prolonged exposure to 3T MRI in the post-mortem brains suggest that MRI scanning in DBS patients may be relatively safe, especially under current guidelines requiring a head receive coil. Subsequent studies exploring the safety of 1.5 T versus 3T MRI in DBS patients should utilize more in depth post-mortem imaging to better simulate the human condition.

The number and nature of emergency department encounters in patients with deep brain stimulators.

UNLABELLED: Deep brain stimulation (DBS) has become an increasingly common modality for control of several neurological disorders such as Parkinson's disease, dystonia, essential tremor (ET), and others. Our experience has demonstrated the need for emergency physicians to familiarize themselves with the potential complications of the DBS device as well as the device itself. Therefore, our aim in this paper was to elucidate the number and nature of DBS and non-DBS presentations to the emergency department (ED) and to educate and familiarize ED physicians about DBS devices and their potential complications. We also aimed to devise a simple protocol for DBS management so that all ED physicians would have access to the knowledge or referral capabilities when managing a DBS patient. The objective of the present study was to review the number and nature of ED encounters in patients with deep brain stimulation (DBS) devices implanted for movement and neuropsychiatric disorders. METHODS: The series of encounters reviewed included 215 unique patients with DBS implantation who were identified using an IRB approved database and a paper chart review. Patients in the study included those implanted at University of Florida (UF), as well as those implanted at outside institutions, so long as they were followed at UF. The cohort included n = 215 DBS patients. 25.6% of all 215 patients presented to the ED at least once, with the most common presentation occurring as a result of a decline in mental status when taking into account all visits (6%). Reasons for presentation to the ED included neurological (54.6%), infections/hardware issues (27.9%), orthopedic/focal problems (10.5%), and medical issues (7%). In total, 29 patients arrived at the ED for DBS related issues (23.2%). Of those who presented to the ED (n = 55), the average age was 53.1 (range 10-80 years). Headache was the most common complaint within the neurological category (22.1%), followed by change in mental status (15.1%), and syncope (9.3%). When examining the data by ED diagnosis, change in mental status occurred most commonly in Parkinson's disease (19.6%). Falls were most common in essential tremor (27.2%), and headache occurred most commonly in the dystonia group (52.1%). Across all diseases, mental status change was the most common indication for an ED encounter (6%). Parkinson disease patients most commonly presented with altered mental status (8%), essential tremor patients revealed a high preponderance of falls (6.5%), and dystonia patients tended to present with headache (7.1%). It was concluded that a large number of patients with DBS will present to the ED for many reasons, the majority of which will not be direct complications of their DBS device. Neurological issues were the most common chief complaint, with individual differences depending on the underlying disease. It is important for ED physicians to consider non-DBS related complaints in the presentation of these unique patients since these issues comprise the majority of the ED visits. However, when properly evaluating these patients, management of their DBS device, or referrals to neurosurgery and neurology, if necessary, are imperative. In addition to device management, regular ED standards of care should apply to this special cohort of patients.