Search

Introduction: Directional deep brain stimulation (DBS) leads have become widely used in the past decade. Understanding the asymmetric stimulation provided by directional leads requires precise knowledge of the exact orientation of the lead in respect to its anatomical target. Recently, the DiODe algorithm was developed to automatically determine the orientation angle of leads from the artifact on postoperative computed tomography (CT) images. However, manual DiODe results are user-dependent. This study analyzed the extent of lead rotation as well as the user agreement of DiODe calculations across the two most common DBS systems, namely, Boston Scientific's Vercise and Abbott's Infinity, and two independent medical institutions. Methods: Data from 104 patients who underwent an anterior-facing unilateral/bilateral directional DBS implantation at either Northwestern Memorial Hospital (NMH) or Albany Medical Center (AMC) were retrospectively analyzed. Actual orientations of the implanted leads were independently calculated by three individual users using the DiODe algorithm in Lead-DBS and patients' postoperative CT images. The deviation from the intended orientation and user agreement were assessed. Results: All leads significantly deviated from the intended 0° orientation (p < 0.001), regardless of DBS lead design (p < 0.05) or institution (p < 0.05). However, the Boston Scientific leads showed an implantation bias toward the left at both institutions (p = 0.014 at NMH, p = 0.029 at AMC). A difference of 10° between at least two users occurred in 28% (NMH) and 39% (AMC) of all Boston Scientific and 76% (NMH) and 53% (AMC) of all Abbott leads. Conclusion: Our results show that there is a significant lead rotation from the intended surgical orientation across both DBS systems and both medical institutions; however, a bias toward a single direction was only seen in the Boston Scientific leads. Additionally, these results raise questions into the user error that occurs when manually refining the orientation angles calculated with DiODe. [ABSTRACT FROM AUTHOR]

Introduction: Deep brain stimulation (DBS) is a common treatment for a variety of neurological and psychiatric disorders. Recent studies have highlighted the role of neuroimaging in localizing the position of electrode contacts relative to target brain areas in order to optimize DBS programming. Among different imaging methods, postoperative magnetic resonance imaging (MRI) has been widely used for DBS electrode localization; however, the geometrical distortion induced by the lead limits its accuracy. In this work, we investigated to what degree the difference between the actual location of the lead's tip and the location of the tip estimated from the MRI artifact varies depending on the MRI sequence parameters such as acquisition plane and phase encoding direction, as well as the lead's extracranial configuration. Accordingly, an imaging technique to increase the accuracy of lead localization was devised and discussed. Methods: We designed and constructed an anthropomorphic phantom with an implanted DBS system following 18 clinically relevant configurations. The phantom was scanned at a Siemens 1.5 Tesla Aera scanner using a T1MPRAGE sequence optimized for clinical use and a T1TSE sequence optimized for research purposes. We varied slice acquisition plane and phase encoding direction and calculated the distance between the caudal tip of the DBS lead MRI artifact and the actual tip of the lead, as estimated from MRI reference markers. Results: Imaging parameters and lead configuration substantially altered the difference in the depth of the lead within its MRI artifact on the scale of several millimeters − with a difference as large as 4.99 mm. The actual tip of the DBS lead was found to be consistently more rostral than the tip estimated from the MR image artifact. The smallest difference between the tip of the DBS lead and the tip of the MRI artifact using the clinically relevant sequence (i.e., T1MPRAGE) was found with the sagittal acquisition plane and anterior-posterior phase encoding direction. Discussion/Conclusion: The actual tip of an implanted DBS lead is located up to several millimeters rostral to the tip of the lead's artifact on postoperative MR images. This distance depends on the MRI sequence parameters and the DBS system's extracranial trajectory. MRI parameters may be altered to improve this localization. [ABSTRACT FROM AUTHOR]

There is a paucity of data regarding the safety of magnetic resonance imaging (MRI) in patients with abandoned epicardial leads. Few studies have reported temperature rises up to 76 °C during MRI at 1.5 T in gel phantoms implanted with epicardial leads; however, lead trajectories used in these experiments were not clinically relevant. This work reports patient-specific RF heating of both capped and uncapped abandoned epicardial lead configurations during MRI at both 1.5 T and 3 T field strengths. We found that leads routed along realistic, patient-derived trajectories generated substantially lower RF heating than the previously reported worst-case phantom experiments. We also found that MRI at the head imaging landmark leads to substantially lower RF heating compared to MRI at the chest or abdomen landmarks at both 1.5 T and 3 T. Our results suggest that patients with abandoned epicardial leads may safely undergo MRI for head imaging, but caution is warranted during chest and abdominal imaging.Clinical Relevance- Patients with abandoned epicardial leads may safely undergo MRI for head imaging, but caution is warranted during chest and abdominal imaging.

Deep brain stimulation (DBS) offers therapeutic benefits to patients suffering from a variety of treatment-resistant neurological and psychiatric disorders. The newest generation of DBS devices now offer directional leads, which utilize segmented electrodes to direct current asymmetrically to the neuronal tissue. Since segmented electrodes offer a larger degree of freedom for contact positioning, it is critical to assess how well the surgically intended and the actual orientation of the lead match to facilitate programming and allow appropriate interpretation of the therapeutic outcome. Postoperative image analysis algorithms, such as DiODe, are commonly used to determine DBS leads' actual orientation. In this work, we used DiODe to compare the deviation between intended and actual orientations of DBS leads across two most commonly implanted directional DBS systems, namely, Boston Scientific Cartesia™ and St. Jude Medical Infinity. This study is the first to investigate the rotation of leads from both DBS systems in a large group of 86 patients. Clinical Relevance- Our results quantify the variability between the surgically intended and actual orientations of Boston Scientific Vercise and St. Jude Medical Infinity DBS systems thus highlighting the need to develop more precise implantation procedures.

Deep brain stimulation (DBS) is an established yet growing treatment for a range of neurological and psychiatric disorders. Over the last decade, numerous studies have underscored the effect of electrode placement on the clinical outcome of DBS. As a result, imaging is now extensively used for DBS electrode localization, even though the accuracy of different modalities in determining the true coordinates of DBS electrodes is less explored. Postoperative magnetic resonance imaging (MRI) is a gold standard method for DBS electrode localization, however, the geometrical distortion induced by the lead's artifact could limit the accuracy. In this work, we investigated to what degree the difference between the true location of the lead's tip and the location of the tip estimated from the MRI artifact varies depending on the MRI sequence parameters, acquisition plane, phase encoding direction, and the implant"s extracranial trajectory. Clinical Relevance- Results will help researchers and clinicians to estimate the true location of DBS leads and contacts from postoperative MRI scans.