The likelihood of rupture of unruptured intracranial aneurysms that were less than 10 mm in diameter was exceedingly low among patients in group 1 and was substantially higher among those in group 2. The risk of morbidity and mortality related to surgery greatly exceeded the 7.5-year risk of rupture among patients in group 1 with unruptured intracranial aneurysms smaller than 10 mm in diameter.

Multiword expressions (MWEs) are a class of linguistic forms spanning conventional word boundaries that are both idiosyncratic and pervasive across different languages. The structure of linguistic processing that depends on the clear distinction between words and phrases has to be re-thought to accommodate MWEs. The issue of MWE handling is crucial for NLP applications, where it raises a number of challenges. The emergence of solutions in the absence of guiding principles motivates this survey, whose aim is not only to provide a focused review of MWE processing, but also to clarify the nature of interactions between MWE processing and downstream applications. We propose a conceptual framework within which challenges and research contributions can be positioned. It offers a shared understanding of what is meant by “MWE processing,” distinguishing the subtasks of MWE discovery and identification. It also elucidates the interactions between MWE processing and two use cases: Parsing and machine translation. Many of the approaches in the literature can be differentiated according to how MWE processing is timed with respect to underlying use cases. We discuss how such orchestration choices affect the scope of MWE-aware systems. For each of the two MWE processing subtasks and for each of the two use cases, we conclude on open issues and research perspectives.

Titanium mesh cages present a viable option for single-stage anterior surgical debridement and reconstruction of vertebral osteomyelitis, without evidence of chronic infection or rejection. When used in conjunction with pedicle screw instrumentation, there is minimal cage settling without loss of sagittal alignment.

Object The aim of this multicenter, prospective study was to determine the spectrum, incidence, and severity of complications during the initial hospitalization of patients with spinal cord injury. Methods The study was conducted at 9 university-affiliated hospitals that comprise the clinical centers of the North American Clinical Trials Network (NACTN) for Treatment of Spinal Cord Injury. The study population comprised 315 patients admitted to NACTN clinical centers between June 25, 2005, and November 2, 2010, who had American Spinal Injury Association (ASIA) Impairment Scale grades of A–D and were 18 years of age or older. Patients were managed according to a standardized protocol. Results The study population was 79% male with a median age of 44 years. The leading causes of injury were falls (37%) and motor vehicle accidents (28%). The distribution of initial ASIA grades were A (40%), B (16%), C (15%), and D (29%). Fifty-eight percent of patients sustained 1 or more severe, moderate, or mild complications. Complications were associated with more severe ASIA grade: 84% of patients with Grade A and 25% of patients with Grade D had at least 1 complication. Seventy-eight percent of complications occurred within 14 days of injury. The most frequent types of severe and moderate complications were respiratory failure, pneumonia, pleural effusion, anemia, cardiac dysrhythmia, and severe bradycardia. The mortality rate was 3.5% and was associated with increased age and preexisting morbidity. Conclusions Knowledge of the type, frequency, time of occurrence, and severity of specific complications that occur after spinal cord injury can aid in their early detection, treatment, and prevention. The data are of importance in evaluating and selecting therapy for clinical trials.

There were significant changes in proximal level ROM immediately after posterior stabilization. However, an additional increase in supradjacent segment ROM was recorded during AR after bilateral facet breach.Subsequent complete laminectomy at the uppermostfixation level further destabilized the supradjacent segment in FE and AR. Therefore, meticulous preservation of the cephalad-most segment facet joints-is paramount to ensure stability.

Object In support of Operation Iraqi Freedom (OIF) and Operation Enduring Freedom-Afghanistan (OEF-A), military neurosurgeons in the combat theater are faced with the daunting task of stabilizing patients in such a way as to prevent irreversible neurological injury from cerebral edema while simultaneously allowing for prolonged transport stateside (5000–7000 miles). It is in this setting that decompressive craniectomy has become a mainstay of far-forward neurosurgical management of traumatic brain injury (TBI). As such, institutional experience with cranioplasty at the Walter Reed Army Medical Center (WRAMC) and the National Naval Medical Center (NNMC) has expanded concomitantly. Battlefield blast explosions create cavitary injury zones that often extend beyond the border of the exposed surface wound, and this situation has created unique reconstruction challenges not often seen in civilian TBI. The loss of both soft-tissue and skull base support along with the need for cranial vault reconstruction requires a multidisciplinary approach involving neurosurgery, plastics, oral-maxillofacial surgery, and ophthalmology. With this situation in mind, the authors of this paper endeavored to review the cranial reconstruction complications encountered in these combat-related injuries. Methods A retrospective database review was conducted for all soldiers injured in OIF and OEF-A who had undergone decompressive craniectomy with subsequent cranioplasty between April 2002 and October 2008 at the WRAMC and NNMC. During this time, both facilities received a total of 408 OIF/OEF-A patients with severe head injuries; 188 of these patients underwent decompressive craniectomies in the theater before transfer to the US. Criteria for inclusion in this study consisted of either a closed or a penetrating head injury sustained in combat operations, resulting in the performance of a decompressive craniectomy and subsequent cranioplasty at either the WRAMC or NNMC. Excluded from the study were patients for whom primary demographic data could not be verified. Demographic data, indications for craniectomy, as well as preoperative, intraoperative, and postoperative parameters following cranioplasty, were recorded. Perioperative and postoperative complications were also recorded. Results One hundred eight patients (male/female ratio 107:1) met the inclusion criteria for this study, 93 with a penetrating head injury and 15 with a closed head injury. Explosive blast injury was the predominant mechanism of injury, occurring in 72 patients (67%). The average time that elapsed between injury and cranioplasty was 190 days (range 7–546 days). An overall complication rate of 24% was identified. The prevalence of perioperative infection (12%), seizure (7.4%), and extraaxial hematoma formation (7.4%) was noted. Twelve patients (11%) required prosthetic removal because of either extraaxial hematoma formation or infection. Eight of the 13 cases of infection involved cranioplasties performed between 90 and 270 days from the date of injury (p = 0.06). Conclusions This study represents the largest to date in which cranioplasty and its complications have been evaluated in a trauma population that underwent decompressive craniectomy. The overall complication rate of 24% is consistent with rates reported in the literature (16–34%); however, the perioperative infection rate of 12% is higher than the rates reported in other studies. This difference is likely related to aspects of the initial injury pattern—such as skull base injury, orbitofacial fractures, sinus injuries, persistent fluid collection, and CSF leakage—which can predispose these patients to infection.

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Neurosurg Focus 28 (5):E4, 20101 P atients with PSIs present very complex, multidisciplinary management challenges for military surgeons. Not only can the patient have immediate and delayed life-threatening damage to organs along the path of the projectile, the spinal column and possibly the neurological structures contained within can also, by definition, suffer injury, the severity of which depends on multiple factors. Spinal cord injury from spinal GSWs is more often a complete lesion with a decreased potential for neurological recovery than with closed trauma. 43There are a number of potential surgical indications, the most controversial of which is whether decompressive laminectomy has any effect on neurological recovery. Medical civilian and military literature is replete with opinions for and against the use of surgery.Although missile characteristics such as size, composition and design are important, the major determinant of the destructive ability of a projectile is velocity at impact and thus the kinetic energy imparted to the surrounding tissue.10 Energy is calculated based on mass and velocity as follows: energy = 1/2mv 2 . Therefore, velocity has a significantly greater effect on energy than projectile mass. Object. Penetrating spinal injury (PSI), although an infrequent injury in the civilian population, is not an infrequent injury in military conflicts. Throughout military history, the role of surgery in the treatment of PSI has been controversial. The US is currently involved in 2 military campaigns, the hallmark of both being the widespread use of various explosive devices. The authors reviewed the evidence for or against the use of decompressive laminectomy to treat PSI to provide a triservice (US Army, Navy, and Air Force) consensus and treatment recommendations for military neurosurgeons and spine surgeons.Methods. A US National Library of Medicine PubMed database search that identified all literature dealing with acute management of PSI from military conflicts and civilian urban trauma centers in the post-Vietnam War period was undertaken.Results. Nineteen retrospective case series (11 military and 8 civilian) met the study criteria. Eleven military articles covered a 20-year time span that included 782 patients who suffered either gunshot or blast-related projectile wounds. Four papers included sufficient data that analyzed the effectiveness of surgery compared with nonoperative management, 6 papers concluded that surgery was of no benefit, 2 papers indicated that surgery did have a role, and 3 papers made no comment. Eight civilian articles covered a 9-year time span that included 653 patients with spinal gunshot wounds. Two articles lacked any comparative data because of treatment bias. Two papers concluded that decompressive laminectomy had a beneficial role, 1 paper favored the removal of intracanal bullets between T-12 and L-4, and 5 papers indicated that surgery was of no benefit.Conclusions. Based on the authors' military and civilian PubMed literature search, most of the evidence s...