Massively parallel neural signal processing: System-on-Chip design with FPGAs.

This work discusses the architectural layout and performance results of a SoC design for parallel neural signal processing. Architectural framework for scalability and scalar reconfigurability are presented. Architectural requirements for massive parallelism in neural recordings are presented.

Sagittal alignment after single cervical disc arthroplasty.

Study Design: Prospective study.

Objectives: To analyze the sagittal balance after single-level cervical disc replacement (CDR) and range of motion (ROM). To define clinical and radiologic parameters those have a significant correlation with segmental and overall cervical curvature after CDR.

The lumbosacral plexus: anatomic considerations for minimally invasive retroperitoneal transpsoas approach.

Purpose: The minimally invasive transpsoas approach can be employed to treat various spinal disorders, such as disc degeneration, deformity, and lateral disc herniation. With this technique, visualization is limited in comparison with the open procedure and the proximity of the lumbar plexus to the surgical pathway is one limitation of this technique. Precise knowledge of the regional anatomy of the lumbar plexus is required for safe passage through the psoas muscle.

Global analysis of sagittal spinal alignment in major deformities: correlation between lack of lumbar lordosis and flexion of the knee.

Introduction: It has become well recognised that sagittal balance of the spine is the result of an interaction between the spine and the pelvis. Knee flexion is considered to be the last compensatory mechanism in case of sagittal imbalance, but only few studies have insisted on the relationship between spino-pelvic parameters and lower extremity parameters. Correlation between the lack of lumbar lordosis and knee flexion has not yet been established.

Surgery improves pain, function and quality of life in patients with spinal metastases: a prospective study on 118 patients.

Purpose: There are few prospective studies on surgical outcomes and survival in patients with metastatic disease to the spine. The magnitude and duration of effect of surgery on pain relief and quality of life remains uncertain. Therefore, the aim of this clinical study was to prospectively evaluate clinical, functional, quality of life and survival outcomes after palliative surgery for vertebral metastases.

Angle measurement reproducibility using EOS three-dimensional reconstructions in adolescent idiopathic scoliosis treated by posterior instrumentation.

Study Design: A reproducibility study was conducted in preoperative and postoperative three-dimensional (3D) measurements for patients operated for adolescent idiopathic scoliosis (AIS).

Objective: To assess the reliability of preoperative and postoperative 3D reconstructions using EOS in patients operated for AIS.

Summary Of Background Data: No prior reliability study of 3D measurements has been performed in the literature for severe scoliosis and for operated patients.

Fuzzy logic-based spike sorting system.

We present a new method for autonomous real-time spike sorting using a fuzzy logic inference engine. The engine assigns each detected event a 'spikiness index' from zero to one that quantifies the extent to which the detected event is like an ideal spike. Spikes can then be sorted by simply clustering the spikiness indices.

Safe working zones using the minimally invasive lateral retroperitoneal transpsoas approach: a morphometric study.

Purpose: The minimally invasive lateral retroperitoneal transpsoas approach is a recent technique developed for lumbar interbody fusion and discectomy. The proximity of the retroperitoneal vessels and ventral nerve roots to the surgical pathway increases the risk of injury to these anatomical structures. A precise knowledge of the regional anatomy of the lumbar plexus is required for safe passage through the psoas muscle.

Incidental durotomy during spine surgery: incidence, management and complications. A retrospective review.

Study Design: Retrospective review of a series of patients who underwent spinal surgery at a single spine unit during a 1 year period.

Objectives: To assess the incidence, treatment, clinical consequence, complications of incidental durotomy during spine surgery and results of 37 months clinical follow-up.

Summary Of Background Data: Incidental durotomy is an underestimated and relatively adverse event during spinal surgery.

Reconfigurable embedded system architecture for next-generation Neural Signal Processing.

This work presents a new architectural framework for next generation Neural Signal Processing (NSP). The essential features of the NSP hardware platform include scalability, reconfigurability, real-time processing ability and data storage. This proposed framework has been implemented in a proof-of-concept NSP prototype using an embedded system architecture synthesized in a Xilinx(®)Virtex(®)5 development board.

Parallel field programmable gate array particle filtering architecture for real-time neural signal processing.

Both linear and nonlinear estimation algorithms have been successfully applied as neural decoding techniques in brain machine interfaces. Nonlinear approaches such as Bayesian auxiliary particle filters offer improved estimates over other methodologies seemingly at the expense of computational complexity. Real-time implementation of particle filtering algorithms for neural signal processing may become prohibitive when the number of neurons in the observed ensemble becomes large.

Total vertebrectomy and spine shortening in the management of acute thoracic spine fracture dislocation: technical note and report of 3 cases.

Study Design: Case report of 3 thoracic spine fracture-dislocations with complete spinal cord section treated by total vertebrectomy--spine shortening through a posterior approach.

Objectives: To assess the usefulness and safety of this surgical technique in the treatment of acute thoracic spine fracture-dislocation.

Summary Of Background: Total vertebrectomy can be used in different nontraumatic disorders.

Neuroanatomical study of the A11 diencephalospinal pathway in the non-human primate.

Background: The A11 diencephalospinal pathway is crucial for sensorimotor integration and pain control at the spinal cord level. When disrupted, it is thought to be involved in numerous painful conditions such as restless legs syndrome and migraine. Its anatomical organization, however, remains largely unknown in the non-human primate (NHP).

[Imaging of the fused spine].

Imaging interpretation of the fused spine requires adequate knowledge of instrumentation and fusion techniques. Familiarity with the normal imaging features is needed in order to detect complications. While such complications are relatively rare, their presence is clinically significant and may lead to repeat surgery.

Estimation of phosphene spatial variability for visual prosthesis applications.

Visual prostheses are the focus of intensive research efforts to restore some measure of useful vision to blind or near-blind patients. The development of such technology is being guided to an extent by tools that simulate prosthesis behavior for healthy sighted subjects in order to assess system requirements and configurations. These simulators, however, typically assume purely deterministic phosphene properties and thus do not apply any variability to phosphene size, intensity, or location.

3D postural balance with regard to gravity line: an evaluation in the transversal plane on 93 patients and 23 asymptomatic volunteers.

Relevance of posture assessment has been reported in case of spine disorders. This study explores the interest in quantifying posture using 3D reconstruction from biplanar X-rays in free standing position and a force plate. 93 patients consulting for spine disorders were divided ('3D deformity', 'sagittal imbalance' and 'mild deformity') and compared with 23 asymptomatic volunteers.

Bayesian auxiliary particle filters for estimating neural tuning parameters.

A common challenge in neural engineering is to track the dynamic parameters of neural tuning functions. This work introduces the application of Bayesian auxiliary particle filters for this purpose. Based on Monte-Carlo filtering, Bayesian auxiliary particle filters use adaptive methods to model the prior densities of the state parameters being tracked.

Two ATS recommended protocols for administration of methacholine are not equal.

Background: The 1999 American Thoracic Society methacholine challenge guidelines stated that the 5-breath dosimeter method of methacholine administration is similar to the 2-minute tidal breath method. Recent data has disputed this assertion. We examined the differences in the diagnosis of asthma using these two methods.

Computerized preoperative planning for correction of sagittal deformity of the spine.

Purpose: Various methods of preoperative planning have been described for the correction of spinal sagittal deformities. They are reliable on condition that the thoracolumbar spine is totally fused and enable only the simulation of pedicle subtraction osteotomy (PSO). In this study, a new theoretical planning that can be used regardless of the etiology of the deformity and the type of osteotomy is described and assessed.

Predictive value of sGaw, FEF(25-75), and FEV1 for development of asthma after a negative methacholine challenge test.

Background: A 20% change in forced expiratory volume in 1 second (FEV(1)) during methacholine challenge testing (MCT) is a reliable marker of asthma. When the FEV(1) decrease is < 20%, there is controversy whether other changes in flows and conductance may be useful. We conducted this study to determine whether changes in sGaw, FEF(25 - 75), and FEV(1) in a negative MCT could predict future occurrence of asthma over a 3-year period.

Research, robots, and reality: A statement on current trends in biorobotics.

While robotics has benefited from inspiration gained from biology, the opposite is not the case: there are few if any cases in which robotic models have lead to genuine insight into biology. We analyze the reasons why biorobotics has been essentially a one-way street. We argue that the development of better tools is essential for progress in this field.

A single-chip signal processing and telemetry engine for an implantable 96-channel neural data acquisition system.

A fully implantable neural data acquisition system is a key component of a clinically viable cortical brain-machine interface. We present the design and implementation of a single-chip device that serves the processing needs of such a system. Our device processes 96 channels of multi-unit neural data and performs all digital processing necessary for bidirectional wireless communication.

Erector spinae muscle changes on magnetic resonance imaging following lumbar surgery through a posterior approach.

Study Design: Prospective randomized study of patients undergoing lumbar arthrodesis.

Objectives: To quantify MRI changes of the erector spinae following lumbar surgery through a posterior approach and the possible protection of these muscles during surgery by the use of cholinergic blockade.

Summary Of Background Data: It has been shown that lumbar spine surgery through a posterior approach can induce iatrogenic lesions in the erector spinae.

The use of curare during anesthesia to prevent iatrogenic muscle damage caused by lumbar spinal surgery through a posterior approach.

Study Design: Prospective randomized study of patients undergoing lumbar arthrodesis.

Objectives: To evaluate the use of curare during anesthesia to limit muscle lesions caused by surgery.

Summary Of Background Data: It has been shown that lumbar spine surgery through a posterior approach can induce iatrogenic lesions in the erector spinae.

Evaluation of spike-detection algorithms for a brain-machine interface application.

Real time spike detection is an important requirement for developing brain machine interfaces (BMIs). We examined three classes of spike-detection algorithms to determine which is best suited for a wireless BMI with a limited transmission bandwidth and computational capabilities. The algorithms were analyzed by tabulating true and false detections when applied to a set of realistic artificial neural signals with known spike times and varying signal to noise ratios.