Purpose: Limited data exist quantifying the risk of adverse radiation effect (ARE) specific to hypofractionated stereotactic radiosurgery (HSRS). We present our analyses of the risk of ARE after 5 daily fractions of HSRS to surgical cavities and intact metastases.
Methods And Materials: One hundred and eighty-seven consecutively treated patients with 118 surgical cavities and 132 intact metastases were retrospectively reviewed.
MR-guided focused ultrasound (MRgFUS) is an emerging technology that can accurately and transiently permeabilize the blood-brain barrier (BBB) for targeted drug delivery to the central nervous system. We conducted a single-arm, first-in-human trial to investigate the safety and feasibility of MRgFUS-induced BBB opening in eloquent primary motor cortex in four volunteers with amyotrophic lateral sclerosis (ALS). Here, we show successful BBB opening using MRgFUS as demonstrated by gadolinium leakage at the target site immediately after sonication in all subjects, which normalized 24 hours later.
View Article and Find Full Text PDFBackground Context: Computer-assisted navigation (CAN) may guide spinal instrumentation, and requires alignment of patient anatomy to imaging. Iterative closest-point (ICP) algorithms register anatomical and imaging surface datasets, which may fail in the presence of geometric symmetry (congruence), leading to failed registration or inaccurate navigation. Here we computationally quantify geometric congruence in posterior spinal exposures, and identify predictors of potential navigation inaccuracy.
View Article and Find Full Text PDFStudy Design: Prospective pre-clinical and clinical cohort study.
Objectives: Current spinal navigation systems rely on a dynamic reference frame (DRF) for image-to-patient registration and tool tracking. Working distant to a DRF may generate inaccuracy.
Background: Cavity stereotactic radiotherapy has emerged as a standard option following resection of brain metastases. However, the optimal approach with either single-fraction or hypofractionated stereotactic radiotherapy (HSRT) remains a significant question.
Objective: To report outcomes for 5-fraction HSRT to the surgical cavity, based on contouring according to a recently reported international consensus guideline.
Of Background Data: Computer-assisted 3-dimensional navigation may guide spinal instrumentation. Optical topographic imaging (OTI) is a novel navigation technique offering comparable accuracy and significantly faster registration workflow relative to current navigation systems. It has previously been validated in open posterior thoracolumbar exposures.
View Article and Find Full Text PDFObjective: Computer-assisted three-dimensional navigation often guides spinal instrumentation. Optical topographic imaging (OTI) offers comparable accuracy and significantly faster registration relative to current navigation systems in open posterior thoracolumbar exposures. We validate the usefulness and accuracy of OTI in minimally invasive spinal approaches.
View Article and Find Full Text PDFBackground: Computer-assisted navigation (CAN) improves the accuracy of spinal instrumentation in vertebral fractures and degenerative spine disease; however, it is not widely adopted because of lack of training, high capital costs, workflow hindrances, and accuracy concerns. We characterize shifts in the use of spinal CAN over time and across disciplines in a single-payer health system, and assess the impact of intra-operative CAN on trainee proficiency across Canada.
Methods: A prospectively maintained Ontario database of patients undergoing spinal instrumentation from 2005 to 2014 was reviewed retrospectively.
The blood-brain barrier (BBB) has long limited therapeutic access to brain tumor and peritumoral tissue. In animals, MR-guided focused ultrasound (MRgFUS) with intravenously injected microbubbles can temporarily and repeatedly disrupt the BBB in a targeted fashion, without open surgery. Our objective is to demonstrate safety and feasibility of MRgFUS BBB opening with systemically administered chemotherapy in patients with glioma in a phase I, single-arm, open-label study.
View Article and Find Full Text PDFIntraoperative image-guided surgical navigation for craniospinal procedures has significantly improved accuracy by providing an avenue for the surgeon to visualize underlying internal structures corresponding to the exposed surface anatomy. Despite the obvious benefits of surgical navigation, surgeon adoption remains relatively low due to long setup and registration times, steep learning curves, and workflow disruptions. We introduce an experimental navigation system utilizing optical topographical imaging (OTI) to acquire the 3D surface anatomy of the surgical cavity, enabling visualization of internal structures relative to exposed surface anatomy from registered preoperative images.
View Article and Find Full Text PDFUltrasound in clinical medicine is most commonly associated with imaging, but can be harnessed to yield an array of biological effects, including thermal ablation of brain tumors. Therapeutic ultrasound has been studied for many years, but only within the last decade has the technology reached a point where it is safe and practical for clinical adoption. Using large, multi-element arrays, ultrasound can be focused through the skull, and combined with MRI for image guidance and real-time thermometry, to create lesions in the brain with millimeter accuracy.
View Article and Find Full Text PDFObjective: To determine changes in post-surgical cavity volume for metastases based on time from surgery, pre-operative tumor dimensions and other predictors, in patients planned for post-operative stereotactic radiosurgery (SRS).
Methods: Patients with resected brain metastases from a primary solid tumor, treated with post-operative surgical cavity SRS from 2008 to 2014 were identified from an institutional prospective database. The segmented three-dimensional (3D) volume of the pre-operative tumor and post-operative surgical cavity were determined based on MRI and percent volume change was calculated.
Purpose To validate ferumoxytol-based quantitative blood oxygenation level-dependent (BOLD) MRI for mapping oxygenation of human infiltrative astrocytomas by using intraoperative measurement of tissue oxygen tension and histologic staining. Materials and Methods Fifteen patients with infiltrative astrocytomas were recruited into this prospective multicenter study between July 2014 and December 2016. Prior to treatment, participants underwent preoperative quantitative BOLD MRI with ferumoxytol to generate tissue oxygen saturation (StO) maps.
View Article and Find Full Text PDFPurpose: Noninvasive frameless systems are increasingly being utilized for head immobilization in stereotactic radiosurgery (SRS). Knowing the head positioning reproducibility of frameless systems and their respective ability to limit intrafractional head motion is important in order to safely perform SRS. The purpose of this study was to evaluate and compare the intrafractional head motion of an invasive frame and a series of frameless systems for single fraction SRS and fractionated/hypofractionated stereotactic radiotherapy (FSRT/HF-SRT).
View Article and Find Full Text PDFSomatosensory evoked potentials (SSEPs) are used for neuroprognosis after severe traumatic brain injury (TBI). However decompressive craniectomy (DC), involving removal of a portion of the skull to alleviate elevated intracranial pressure, is associated with an increase in SSEP amplitude. Accordingly, SSEPs are not available for neuroprognosis over the hemisphere with DC.
View Article and Find Full Text PDFCurr Treat Options Oncol
October 2017
Newly diagnosed elderly patients (age > 65-70 years) with glioblastoma should be treated with a patient-centred approach by a multi-disciplinary team. Chronological age alone should not be considered as a contraindication to treatment with maximal safe surgical resection. A 3-week course of adjuvant radiation and chemotherapy is appropriate in selected elderly patients with favourable Karnofsky performance status (KPS) who cannot tolerate a longer 6-week course of fractionated radiotherapy.
View Article and Find Full Text PDFBackground: Intraosseous vascular anomalies (IOVA) are rare in the craniofacial skeleton and present a diagnostic and therapeutic challenge. This study aims to describe the clinical management based on a large case series.
Methods: A retrospective chart review was performed and 9 IOVA were identified over a 15-year period.
A trans-agency workshop on the blood-brain interface (BBI), sponsored by the National Heart, Lung and Blood Institute, the National Cancer Institute and the Combat Casualty Care Research Program at the Department of Defense, was conducted in Bethesda MD on June 7-8, 2016. The workshop was structured into four sessions: (1) blood sciences; (2) exosome therapeutics; (3) next generation in vitro blood-brain barrier (BBB) models; and (4) BBB delivery and targeting. The first day of the workshop focused on the physiology of the blood and neuro-vascular unit, blood or biofluid-based molecular markers, extracellular vesicles associated with brain injury, and how these entities can be employed to better evaluate injury states and/or deliver therapeutics.
View Article and Find Full Text PDFOutcome after severe traumatic brain injury (TBI) differs substantially between hospitals. Explaining this variation begins with understanding the differences in structures and processes of care, particularly at intensive care units (ICUs) where acute TBI care takes place. We invited trauma medical directors (TMDs) from 187 centers participating in the American College of Surgeons Trauma Quality Improvement Program (ACS TQIP) to complete a survey.
View Article and Find Full Text PDFBackground: The hospital volume-outcome relationship in severe traumatic brain injury (TBI) population remains unclear.
Objective: To examine the relationship between volume of patients with severe TBI per hospital and in-hospital mortality, major complications, and mortality following a major complication (ie, failure to rescue).
Methods: In a multicenter cohort study, data on 9255 adults with severe TBI were derived from 111 hospitals participating in the American College of Surgeons Trauma Quality Improvement Program over 2009-2011.
Background Context: Spinal intraoperative computer-assisted navigation (CAN) may guide pedicle screw placement. Computer-assisted navigation techniques have been reported to reduce pedicle screw breach rates across all spinal levels. However, definitions of screw breach vary widely across studies, if reported at all.
View Article and Find Full Text PDFEarly access to specialized care after acute traumatic spinal cord injury (SCI) is associated with improved outcomes. However, many SCI patients do not receive timely access to such care. To characterize and quantify patients' pathway to definitive care and surgery post SCI, and to identify factors that may delay expeditious care, a population based cohort study was performed in Ontario.
View Article and Find Full Text PDFBackground: Economic evaluations provide a unique opportunity to identify the optimal strategies for the diagnosis and management of traumatic brain injury (TBI), for which uncertainty is common and the economic burden is substantial.
Objective: The objective of this study was to systematically review and examine the quality of contemporary economic evaluations in the diagnosis and management of TBI.
Methods: Two reviewers independently searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, NHS Economic Evaluation Database, Health Technology Assessment Database, EconLit, and the Tufts CEA Registry for comparative economic evaluations published from 2000 onward (last updated on August 30, 2013).
J Neurosurg Pediatr
November 2015
OBJECT Well-designed studies linking intracranial pressure (ICP) monitoring with improved outcomes among children with severe traumatic brain injury (TBI) are lacking. The main objective of this study was to examine the relationship between ICP monitoring in children and in-hospital mortality following severe TBI. METHODS An observational study was conducted using data derived from 153 adult or mixed (adult and pediatric) trauma centers participating in the American College of Surgeons (ACS) Trauma Quality Improvement Program (TQIP) and 29 pediatric trauma centers participating in the pediatric pilot TQIP between 2010 and 2012.
View Article and Find Full Text PDFThis is the case of a 34-year-old woman with severe narcolepsy with cataplexy who experienced a dramatic reduction in cataplexy symptoms after resection of a right parietal astrocytoma. The patient underwent detailed neurological exam, neuropsychological testing, polysomnography and multiple sleep latency testing following surgery.
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