221 research outputs found
Stimulated Raman Histology for Intraoperative Guidance in the Resection of a Recurrent Atypical Spheno-orbital Meningioma: A Case Report and Review of Literature
Meningiomas are the most common intracranial, extra-axial neoplasms and account for a significant proportion of all central nervous system (CNS) tumors. Regardless of the grade, treatment typically involves upfront surgical resection. However, in many instances, especially in meningiomas arising from the skull base, complete removal is often difficult given the close proximity to important anatomic structures. In this report, we discuss the use of stimulated Raman histology as a means to identify tissue boundaries during the resection of an extensive, recurrent, atypical spheno-orbital meningioma. We report a 75-year-old male with a history of a prior left frontotemporal craniotomy for a grade II meningioma three years prior, who presented with worsening left-sided visual loss and pronounced temporal bossing. Repeat magnetic resonance imaging (MRI) revealed a recurrent left spheno-orbital tumor suggestive of a meningioma extending into the middle cranial fossa, the lateral orbit, and the temporalis muscle. He underwent an extended orbito-pterional craniotomy, and intraoperative stimulated Raman histology aided in the identification of tumor margins within the orbit and the temporalis muscle in order to better preserve the normal orbital contents and muscle bulk of the infratemporal fossa. This case demonstrates the utility of stimulated Raman histology during the resection of invasive skull base tumors. The immediate intraoperative Raman histologic sections can clearly identify tissue boundaries and thus help preserve important anatomic structures. Continued development of this method can potentially improve the accuracy of intraoperative diagnoses and guide surgeons during tumor resections near eloquent anatomical regions or important normal structures
Interfacial Reactions of Ozone with Surfactant Protein B in a Model Lung Surfactant System
Oxidative stresses from irritants such as hydrogen peroxide and ozone (O_3) can cause dysfunction of the pulmonary surfactant (PS) layer in the human lung, resulting in chronic diseases of the respiratory tract. For identification of structural changes of pulmonary surfactant protein B (SP-B) due to the heterogeneous reaction with O_3, field-induced droplet ionization (FIDI) mass spectrometry has been utilized. FIDI is a soft ionization method in which ions are extracted from the surface of microliter-volume droplets. We report structurally specific oxidative changes of SP-B_(1−25) (a shortened version of human SP-B) at the air−liquid interface. We also present studies of the interfacial oxidation of SP-B_(1−25) in a nonionizable 1-palmitoyl-2-oleoyl-sn-glycerol (POG) surfactant layer as a model PS system, where competitive oxidation of the two components is observed. Our results indicate that the heterogeneous reaction of SP-B_(1−25) at the interface is quite different from that in the solution phase. In comparison with the nearly complete homogeneous oxidation of SP-B_(1−25), only a subset of the amino acids known to react with ozone are oxidized by direct ozonolysis in the hydrophobic interfacial environment, both with and without the lipid surfactant layer. Combining these experimental observations with the results of molecular dynamics simulations provides an improved understanding of the interfacial structure and chemistry of a model lung surfactant system subjected to oxidative stress
MR-Guided Laser Interstitial Thermal Therapy for Treatment of Brain Tumors
Minimally invasive technologies for intracranial lesions are a rapidly growing area of surgical neuro-oncology. Magnetic resonance (MR)-guided laser interstitial thermal therapy (LITT) is novel adjunctive therapy for patients who are poor candidates for open surgical resection. Recent developments in modern stereotaxy, fiber optics, and MR thermography imaging have improved the safety profile of LITT, enabling its emergence as an attractive alternative adjunct therapy for intracranial lesions which are deep-seated, refractory to standard therapies, or in patients with multiple comorbidities. In this chapter, we review the technological principles underlying LITT and provide a comprehensive, up-to-date summary of the evidence regarding the indications, outcomes, and limitations of LITT for a diverse array of intracranial tumors, including dural-based lesions, metastases, gliomas, and radiation necrosis
Effects of Obesity on Cervical Disc Arthroplasty Complications
Objective High body mass index is a well-established modifiable comorbidity that is known to increase postoperative complications in all types of surgery, including spine surgery. Obesity is increasing in prevalence amongst the general population. As this growing population of obese patients ages, understanding how they faire undergoing cervical disc arthroplasty (CDA) is important for providing safe and effective evidence-based care for cervical degenerative pathology. Methods Our study used the Healthcare Cost and Utilization Project’s National Inpatient Sample to assess patients undergoing CDA comparing patient characteristics and outcomes in nonobese patients to obese patients from 2004 to 2014. Results Our study found a significant increase in the overall utilization of CDA as a treatment modality (p = 0.012) and a statistically significant increase in obese patients undergoing CDA (p < 0.0001) from 2004 to 2014. Obesity was identified as an independent risk factor associated with increased rates of inpatient neurologic complications (odds ratio [OR], 6.99; p = 0.03), pulmonary embolus (OR, 5.41; p = 0.05), and wound infection (OR, 6.97; p < 0.001) in patients undergoing CDA from 2004 to 2014. Conclusion In patients undergoing CDA, from 2004 to 2014, obesity was identified as an independent risk factor with significantly increased rates of inpatient neurologic complications, pulmonary embolus and wound infection. Large prospective trials are needed to validate these findings
Sustainability of terrestrial carbon sequestration: A case study in Duke Forest with inversion approach
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95430/1/gbc891.pd
Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures
Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo
Recommended from our members
How to Start Your Radial Practice
Once committed to converting your practice to the radial approach, there are several tips and tricks that the authors suggest to improve your journey. Radial access is not difficult, but there are several strategies that are counterintuitive that can make the difference between building a successful radial practice and going back to femoral access. Understanding the learning journey having traveled it ourselves, the audience can receive the benefit of us having already tread the path and defined the optimal way to convert your practice to a radial first practice. The nuances of setting up a radial neurointerventional practice are reviewed
Recommended from our members
Percutaneous Instrumentation of a Complex Lumbar Spine Fracture with Bilateral Pedicle Dissociation: Case Report and Technical Note
Abstract
Background and Study Objective
 Complex traumatic lumbar spine fractures are difficult to manage and typically occur in younger patients. Surgical immobilization for unstable fractures is an accepted treatment but can lead to future adjacent-level disease. Furthermore, large variations in fracture morphology create significant difficulties when attempting fixation. Therefore, a surgical approach that considers both long-term outcomes and fracture type is of utmost importance. We present a novel technique for percutaneous fixation without interbody or posterolateral fusion in a young patient with bilateral pedicle dissociations and an acute-onset incomplete neurologic deficit.
Case Description
 A 20-year-old man involved in a motorcycle accident presented with unilateral right lower extremity paresis and sensory loss with intact rectal tone and no saddle anesthesia. Lumbar computed tomography (CT) demonstrated L2 and L3 fractures associated with bilateral pedicle dislocations. Lumbar magnetic resonance imaging showed draping of the conus medullaris/cauda equina anteriorly over the kyphotic deformity at L2 with minimal associated canal stenosis at L2 and L3. He was treated with emergent percutaneous fixation of the fracture segment without interbody or posterolateral fusion. Decompression was not performed because of the negligible amount of canal stenosis and high likelihood of cerebrospinal fluid leakage due to dural tears from the fractures. Surgical fixation of the L2 vertebra was achieved by cannulating the left pedicle with an oversized tap while holding the right pedicle in place with a normal tap and then driving screws into the left and right pedicles, respectively, thus reducing the free-floating fracture segment. At 18 months after surgery, a follow-up CT demonstrated good cortication across the prior pedicle fractures, and the instrumentation was removed without any obvious signs of instability or disruption of the alignment at the thoracolumbar junction.
Conclusion
 We present a novel technique for percutaneous reduction and fixation of bilateral pedicle fractures with significant dissociation from the vertebral body, associated neural compression from the kyphotic deformity, and minimal spinal canal stenosis. Furthermore, we argue that early fixation and reduction of the fracture prevented irreversible neurologic compromise, and the absence of interbody or posterolateral fusion ultimately preserved the spinal mobility of the patient once the hardware was removed
Recommended from our members
Endoscopic third ventriculostomy inpatient failure rates compared with shunting in post-hemorrhagic hydrocephalus of prematurity
Purpose Endoscopic third ventriculostomy (ETV) has gained traction as a method for treating post-hemorrhagic hydrocephalus of prematurity (PHHP) in an effort to obviate lifelong shunt dependence in neonates. However, data remains limited regarding inpatient failures. Methods A retrospective analysis of the NIS between 1998 and 2014 was performed. Discharges with age < 1 year and ICD-9-CM codes indicating intraventricular hemorrhage of prematurity (772.1x) and ETV/shunt (02.22 and 02.3x) were included. Patients with ICD-9-CM codes for ventricular drain/reservoir (02.21) were excluded to prevent confounding. Time trend series plots were created. Yearly trends were quantified using logarithmic regression analysis. Kaplan-Meier curves were utilized to analyze time to treatment failure. Time to failure for each treatment was compared using log-rank. Results A total of 11,017 discharges were identified. ETV was more likely to be utilized at < 29 weeks gestational age (p = 0.0039) and birth weight < 1000 g (p = 0.0039). Shunts were less likely to fail in older and heavier newborns (OR 0.836 p = 0.00456, OR 0.828 p = 0.0001, respectively). Those initially shunted had lower failure rates compared with ETV (OR 0.44, p < 0.0001) but time to failure was longer with ETV (p = 0.04562). 79.5% of ETVs that failed were shunted after the first failure. Shunts were much less likely to undergo ETV if they failed (OR 0.21, p < 0.0001). Higher grade IVH was predictive of shunt failure but not ETV (OR 2.36, p = 0.0129). Conclusions Although ETV can be effective in PHHP, it has a much higher initial failure rate than shunting and should thus be chosen based on a multifactorial approach
Recommended from our members
Commentary: Glomus Vagale Tumor Resection: 2-Dimensional Operative Video
- …