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Frame-based stereotactic localization is an important step for targeting during a surgical procedure. The motion may cause artifacts in this step reducing the accuracy of surgical targeting. While modeling of motion in real-life scenarios may be difficult, herein we analyzed the case where motion was suspected to impact the localization step. In this case, a scan with and without motion was performed with a 3N localizer, allowing for a thorough analysis. Pseudo-bending of straight rods was seen when analyzing the data. This pseudo-bending appears to occur because head-frame motion during imaging acquisition decreases the accuracy of the subsequent reconstruction, which depends on Digital Imaging and Communications in Medicine (DICOM) metadata to specify the slice-to-slice location that assumes embedded object stability. Comparison of single-slice and multi-slice stereotactic localization allowed for comparative errors for each slice in a volume. This comparative error demonstrated low error when the patient was under general anesthesia and presumed not to have moved, whereas a higher error was present during the scan with motion. Pseudo-bending can be corrected by using only localizer fiducial-based information to reorient the pixels in the volume, thus creating a reoriented localizer scan. Finally, targeting demonstrated a low error of 0.1 mm (+/- 0.1 mm) using this reoriented localizer scan, signifying that this method could be used to improve or recover from motion problems. Finally, it is concluded that stability and elimination of motion for all images utilized for stereotactic surgery are critical to ensure the best possible accuracy for the procedure.

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Obsessive-compulsive disorder (OCD), a leading cause of disability, affects ~1-2% of the population, and can be distressing and disabling. About 1/3 of individuals demonstrate poor responsiveness to conventional treatments. A small proportion of these individuals may be deep brain stimulation (DBS) candidates. Candidacy is assessed through a multidisciplinary process including assessment of illness severity, chronicity, and functional impact. Optimization failure, despite multiple treatments, is critical during screening. Few patients nationwide are eligible for OCD DBS and thus a multi-center approach was necessary to obtain adequate sample size. The study was conducted over a six-year period and was a NIH-funded, eight-center sham-controlled trial of DBS targeting the ventral capsule/ventral striatum (VC/VS) region. There were 269 individuals who initially contacted the sites, in order to achieve 27 participants enrolled. Study enrollment required extensive review for eligibility, which was overseen by an independent advisory board. Disabling OCD had to be persistent for ≥5 years despite exhaustive medication and behavioral treatment. The final cohort was derived from a detailed consent process that included consent monitoring. Mean illness duration was 27.2 years. OCD symptom subtypes and psychiatric comorbidities varied, but all had severe disability with impaired quality of life and functioning. Participants were randomized to receive sham or active DBS for three months. Following this period, all participants received active DBS. Treatment assignment was masked to participants and raters and assessments were blinded. The final sample was consistent in demographic characteristics and clinical features when compared to other contemporary published prospective studies of OCD DBS. We report the clinical trial design, methods, and general demographics of this OCD DBS sample.

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BACKGROUND: Efficacy in deep brain stimulation (DBS) is dependent on precise positioning of electrodes within the brain. Intraoperative fluoroscopy, computed tomography (CT), or magnetic resonance imaging are used for stereotactic intraoperative localization (StIL), but the utility of biplanar X-ray has not been evaluated in detail. OBJECTIVE: To determine if analysis of orthogonal biplanar X-rays using graphical analysis (GA), ray tracing (RT), and/or perspective projection (PP) can be utilized for StIL. METHODS: A review of electrode tip positions comparing postoperative CT to X-ray methods was performed for DBS operations containing orthogonal biplanar X-ray with referential spheres and pins. RESULTS: Euclidean (Re) errors for final DBS electrode position on intraoperative X-rays vs postoperative CT using GA, RT, and PP methods averaged 1.58 mm (±0.75), 0.74 mm (±0.45), and 1.07 mm (±0.64), respectively (n = 56). GA was more accurate with a ventriculogram. RT and PP predicted positions that correlated with third ventricular structures on ventriculogram cases. RT was the most stable but required knowledge of the geometric setup. PP was more flexible than RT but required well-distributed reference points. A single case using the O-arm demonstrated Re errors of 0.43 mm and 0.28 mm for RT and PP, respectively. In addition, these techniques could also be used to calculate directional electrode rotation. CONCLUSION: GA, RT, and PP can be employed for precise StIL during DBS using orthogonal biplanar X-ray. These methods may be generalized to other stereotactic procedures or instances of biplanar imaging such as angiograms, radiosurgery, or injection therapeutics.

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INTRODUCTION: Facial pain is often debilitating and can be characterized by a sharp, stabbing, burning, aching, and dysesthetic sensation. Specifically, trigeminal neuropathic pain (TNP), anesthesia dolorosa, and persistent idiopathic facial pain (PIFP) are difficult diseases to treat, can be quite debilitating and an effective, enduring treatment remains elusive. METHODS: We retrospectively reviewed our early experience with stimulation involving the trigeminal and sphenopalatine ganglion stimulation for TNP, anesthesia dolorosa, and PIFP between 2010-2014 to assess the feasibility of implanting at these ganglionic sites. Seven patients received either trigeminal and/or sphenopalatine ganglion stimulation with or without peripheral nerve stimulation, having failed multiple alternative modalities of treatment. The treatments were tailored on the physical location of pain to ensure regional coverage with the stimulation. RESULTS: Fluoroscopy or frameless stereotaxy was utilized to place the sphenopalatine and/or trigeminal ganglion stimulator. All patients were initially trialed before implantation. Trial leads implanted in the pterygopalatine fossa near the sphenopalatine ganglion were implanted via transpterygoid (lateral-medial, infrazygomatic) approach. Trial leads were implanted in the trigeminal ganglion via percutaneous Hartel approach, all of which resulted in masseter contraction. Patients who developed clinically significant pain improvement underwent implantation. The trigeminal ganglion stimulation permanent implants involved placing a grid electrode over Meckel's cave via subtemporal craniotomy, which offered a greater ability to stimulate subdivisions of the trigeminal nerve, without muscular (V3) side effects. Two of the seven overall patients did not respond well to the trial and were not implanted. Five patients reported pain relief with up to 24-month follow-up. Several of the sphenopalatine ganglion stimulation patients had pain relief without any paresthesias. There were no electrode migrations or post-surgical complications. CONCLUSIONS: Refractory facial pain may respond positively to ganglionic forms of stimulation. It appears safe and durable to implant electrodes in the pterygopalatine fossa via a lateral transpterygoid approach. Also, implantation of an electrode grid overlying Meckel's cave appears to be a feasible alternative to the Hartel approach. Further investigation is needed to evaluate the usefulness of these approaches for various facial pain conditions.

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Deep brain stimulation is a rapidly expanding therapy initially designed for the treatment of movement disorders and pain syndromes. The therapy includes implantation of electrodes in specific targets of the brain, delivering programmable small and safe electric impulses, like a pacemaker, that modulates both local and broad neurologic networks. The effects are thought to primarily involve a focus in the brain, probably inhibitory, which then restores a network of neural circuitry. Psychiatric diseases can be refractory and severe, leading to high medical costs, significant morbidity, and even death. Whereas surgery for psychiatric disease used to include destructive procedures, deep brain stimulation allows safe, reversible, and adjustable treatment that can be tailored for each patient. Deep brain stimulation offers new hope for these unfortunate patients, and the preliminary results are promising.

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