bluuebunny/crossref_metadata_2025 huggingface dataset:
Incidence of and Risk Factors for Sexual Orientation–Related Physical Assault Among Young Men Who Have Sex With Men
Authors: Lampinen Thomas M. , Chan Keith , Anema Aranka , Miller Mary Lou , Schilder Arn J. , Schechter Martin T. , Hogg Robert Stephen , Strathdee Steffanie A.
Published: April 2008

Objectives. We sought to determine incidence of, prevalence of, and risk factors for sexual orientation–related physical assault in young men who have sex with men (MSM).

Methods. We completed a prospective open cohort study of young MSM in Vancouver, British Columbia, surveyed annually between 1995 and 2004. Correlates of sexual orientation–related physical assault before enrollment were identified with logistic regression. Risk factors for incident assaults were determined with Cox regression.

Results. At enrollment, 84 (16%) of 521 MSM reported ever experiencing assault related to actual or perceived sexual orientation. Incidence was 2.3 per 100 person-years; cumulative incidence at 6-year follow-up was 10.8 per 100 person-years. Increased risk of incident sexual orientation–related physical assault was observed among MSM 23 years or younger (relative hazard=3.1; 95% confidence interval [CI] = 1.6, 5.8), Canadian Aboriginal people (relative hazard = 3.0; 95% CI=1.4, 6.2), and those who previously experienced such assault (relative hazard=2.5; 95% CI=1.3, 4.8).

Conclusions. These data underscore the need for increased public awareness, surveillance, and support to reduce assault against young MSM. Such efforts should be coordinated at the community level to ensure that social norms dictate that such acts are unacceptable.
Turning Loss Into Legislation
Authors: Labella Angelena , Singh Devika
Published: April 2008

Same-sex partnerships encounter tremendous challenges in the context of healthcare, including empowerment to act on behalf of loved ones. We share challenges faced by two women who confronted this issue head-on when their same-sex partners were critically, and, in one case, fatally, injured.

In both cases, hospitals initially refused to recognize these women as next of kin; one woman endured years of legal battles in her struggle to win the right to care for her partner. The other testified about her heartrending experience before the Washington State Judiciary Committee, helping to inspire legislation regarding rights for visitation and end-of-life decisions on behalf of same-sex partners.

We seek to remind health care providers of the limitations of current laws and to inspire them to support change.
Expandable Liner Hanger System Enhances Liner Installations by Providing Viable Solutions that Overcome Deployment and Installation Issues in Low-Pressure Reservoirs
Authors: Wardak Ajmal , Williford James , Al-Madlouh Mohammed
Published: April 2008

Low-pressure reservoir characteristics are not often considered as a contributor to installation failure during deployment of conventional hydraulic-set liner hanger systems. Often, this situation occurs in cases where there is a sudden change in the well properties. If this phenomenon occurs, the outcome of a job can be changed from success to a failure. These low-pressurized reservoirs are considered as being capable of being maintained with fluid weight (balanced) rather than as candidate for one that is controllable by lighter-weight fluids (less than 8.3ppg) (underbalance). In the balanced wells, liner installation issues can range from sudden high-rate fluid loss causing differential pressure sticking of the liner, inability to get to depth, or inability to place cement around the liner forming the primary liner top seal.

In the underbalanced wells, issues such as difficulty in running the liner to bottom, and premature setting of the liner hanger during deployment of the liner can be seen, and during the critical stage of cementing the liner, problems such as inability to circulate at rates and pressures, inability to move the liner during the cement job, and inability to provide a liner-top seal prior to releasing the running tool can result. Such are the issues faced by operators in different areas of the globe.

A solution to these issues has been identified. An expandable liner hanger (ELH) system, which allows the annulus fluid to be isolated from the work string fluid during deployment and throughout the cement job because of its pressure-balanced configuration can resolve these problems. In addition, the ELH system can be set up for liner drilling, enabling the liner to be drilled through the low pressure reservoir, the shoe to be cemented, and the liner top to be isolated upon setting. Multiple jobs have been performed successfully in this manner, saving the operator several days of rig time through one or more benefits provided by the system; i.e., getting the liner to bottom, providing a premium cement bond, and eliminating remedial cementing jobs. Selected cases concerning low-pressured well types will be the focus of this paper.
Field Trials of Fiber Assisted Stimulation in Saudi Arabia: An Innovative Non-Damaging Technique for Achieving Effective Zonal Coverage During Acid Fracturing
Authors: Al-Ismail Maytham I. , Al-Harbi Moataz M. , Al-Harbi Abdulaziz K. , Ramanathan Venkateshwaran
Published: April 2008

Acid fracturing has been part of Saudi Aramco's gas development strategy to maximize productivity from for vertical wells in the Khuff carbonates over the last several years. During acid fracturing, the wormholes created by the reaction with the formation results in excessive fluid loss. Controlling fluid loss is one of the key objectives in acid fracturing treatments to be able to create longer and wider fractures, and hence maximize well productivity. Alternating stages of polymer pad with diesel emulsified acid for deeper penetration and in-situ gelled acid, a polymer-based system, have been extensively used in most fracture treatements in an attempt to control excessive leak-off during the treatment.

The vertical well treatments target several reservoir sub-layers with varying degrees of porosity and permeability contrast. These layers are often divided by lithological streaks that make vertical communication challenging.Hence in many instances acid fracturing ends up over-stimulating the highest reservoir quality zones and by-passing or under-stimulating the other zones.Consequently, the zonal contribution from these wells is not optimal.

A pilot involving use of a new degradable fiber technology designed to achieve effective acid diversion during acid fracturing was recently implemented in several gas producers.The pilot comprised field trials in wells with similar reservoir characteristics and multiple porosity lobes.The treatments were designed and pumped with alternating stages of acid and fiber-laden polymer based pad fluid. The viscosity increase achieved in the pad by the addition of fibers and its bridging mechanism plugged off the just stimulated zones effectively, thus diverting the new stage of acid into the unstimulated porous zones. The fibers degrade and hydrolyze with temperature and time so no reservoir damage occurs.

This paper discusses the planning and design processes leading to the successful implementation of the technology, and the excellent post-stimulation results achieved. Bottomhole pressure gauge data were collected, and production logs were run to ascertain the effectiveness of the new technology.Results from the conducted pilot, along with production history comparisons with offset producers will be discussed.
A New Record of Coiled Tubing Reach in Open Hole Horizontal Wells Using Tractor and Friction Reducer in Saudi Arabia History: A Case Study
Authors: Bawaked Waleed K. , Beheiri Faisal I. , Saudi Mohammed M.
Published: April 2008

Energy sustainability is heavily dependent on sustainability of hydrocarbon production that in turn depends on maximizing the recovery and sweep efficiency. The natural energy supporting hydrocarbon production is facilitated by the dominant reservoir drive mechanism. Maintaining this energy drive at optimum level, calls for a continuous injectivity improvement and uniform distribution of injection. This could be achieved by drilling and stimulating extended reach horizontal injectors.Utilizing Drill Pipe (DP) for stimulating the extended reach interval proved to be ineffective and costly.Stimulation using Coiled Tubing (CT) is effective and less in cost; however, reaching the target depth is a challenge.

A new best practice, utilizing a combination of CT tractor and friction reducer agents, enabled the CT to reach the target depth and the stimulation fluid to cover the whole horizontal injection interval. This achievement was a result of proper production engineering planning and several meetings and technical discussions with the service provider.

Preparing the young professionals for the future is an important part of energy sustainability. Young professionals were involved in these activities to develop their skills and capability and get them ready for the future.

A new record of 9,448 ft were achieved which is the longest in Saudi Aramco history.

The application of this combination of techniques could be used in the future to avoid the expensive alternative of stimulation using DP while the rig is on location and to provide better post injectivity performance since it is proved so.
Optimizing Production Facilities Using None-Radio Active Source MPFM in Ghawar Field in Saudi Aramco
Authors: Al-Shuwaikhat Hisham I. , Al-Buhassan Shaker A. , Al-Saadoun Turki F. , Al-Driweesh Saad M.
Published: April 2008

Oil production facilities are continuously being optimized in Saudi Aramco to further simplify the production operations, increase the system efficiency, reduce the operational cost and improve the separated oil recovery. A Gas Oil Separation Plant (GOSP) in Saudi Aramco oil field is a key facility that separates the produced oil from the production stream. Technical enhancement in this facility has reduced the loss of recoverable oil and thus improved the revenue.

New technology item such as None-Radio Active Source Multi-Phase Flow Meter (NRAS MPFM) is being introduced to enhance the well testing and monitoring and to help in getting better results for quicker remedial action and decision making. NRAS MPFM will eventually replace the Radio Active Source Multi-Phase Flow Meter (RAS MPFM) which has been utilized in oil and gas market previously.

Wells are tested with faster frequency and necessary steps are being taken to optimize the well production rates. This paper will illustrate the challenges and successes of testing oil producer wells using NRAS MPFM in series with the existing GOSP conventional High Pressure Test Trap separators (HPTT). Proper training and education of employee has increased the general awareness on oil wastage. Moreover, uninterrupted well flow is being made possible by regular maintenance and checks of surface facilities which has improved the safety of operation and reduced the downtime.
Utilizing Mud Logs for Optimal Formation Evaluation and Guidance in Formation Testing Decisions
Authors: AlGhamdi Tareq M. , AlWaheed Hilal , Bradford Charles , Cheshire Stephen
Published: April 2008

Mud logging technology has advanced to a stage where an increasing number of professionals use this data to perform quantitative reservoir evaluation and reservoir fluid typing. The use of mud logging services in Saudi Aramco prior to 2003 was limited to areas where H2S detection was of great importance in reservoirs where pyrolysis was being performed on cuttings to identify the presence of tar.

In Saudi Aramco Exploration & Delineation wells, well site geologists describe cuttings and mud engineers use simple gas detectors to monitor gas shows in the mud returns. To implement mud logging on a wider scale in Saudi Aramco represented a significant change in procedures. The mud logging unit had to improve formation evaluation, reduce well testing and/or aid in the discovery of reserves that might otherwise be overlooked.

The process of evaluating different mud logging suppliers and systems resulted in a large body of data across many oil, gas and water bearing reservoirs. Through a series of short case examples the benefit of using these systems is examined.
The Impact of the Downhole Formation Tester with Comprehensive Data Integration in Pre-Khuff Hydrocarbon Exploration
Authors: Al-Jeshi Hussain A. , Bradford Charles , Zeybek Murat
Published: April 2008

The process of defining the fluid and reservoir properties of a hydrocarbon discovery represents a significant challenge to the industry. The practice of performing a drill stem test (DST) over a significant reservoir interval and attributing the properties of the produced fluid to a single reservoir fluid compartment is problematic. Overlooking the variation in fluid properties that can and do exist in what appears to be a homogeneous reservoir on a typical log analysis can lead to incorrect assumptions about the economic value of the hydrocarbon discovery, the production facilities required to produce the resource and the predicted ultimate recovery.

Recent advances in wireline formation testers have enabled the determination of several fluid properties, including fluid compositions in real time. In addition, mini-DST or Interval Pressure Transient Testing (IPTT) can be carried out at Downhole Fluid Analysis (DFA) stations to provide more representative and accurate mobility/permeability distributions of reservoir layers7 for reservoir characterization.

In this paper, examples illustrate how the use of this technology helped Saudi Aramco effectively address these challenges.
Population Estimates of Snowshoe Hares in the Southern Rocky Mountains
Authors: ZAHRATKA JENNIFER L. , SHENK TANYA M.
Published: April 2008

Abstract: In 1999 Canada lynx (Lynx canadensis) were reintroduced to the southern Rocky Mountains and in 2000 the species was listed as threatened under the Endangered Species Act in the contiguous United States (Colorado Division of Wildlife 2000, U.S. Fish and Wildlife Service 2000). To better evaluate the progress of this reintroduction, we conducted field studies to estimate population densities of snowshoe hares (Lepus americanus), the primary prey of lynx in Colorado, USA. We conducted our field studies in southwestern Colorado in winters 2002 and 2003. We estimated population densities in forested stands of mature Engelmann spruce (Picea engelmannii)‐subalpine fir (Abies lasiocarpa) and mature lodgepole pine (Pinus contorta) using mark‐recapture data and 3 methods for estimating effective area trapped: half trap interval, mean maximum distance moved (MMDM), and half MMDM. In Engelmann spruce‐subalpine fir, we found density estimates ranged from 0.08 ± 0.03 (SE) hares/ha to 1.32 ± 0.15 hares/ha and in lodgepole pine, density estimates ranged from 0.06 ± 0.01 hares/ha to 0.34 ± 0.06 hares/ha, depending on year and method used for estimating effective area trapped. Our density estimates are similar to those reported at the low phase of the hare cycle in populations to the north (<0.1–1.1 hares/ha), where Canada lynx persist (Hodges 2000a). Although density estimates are a useful comparative tool, they depend upon methods used to estimate effective area trapped. Therefore, we urge caution in comparing our density estimates with those from other areas, which may have used dissimilar methods. We also examined effects of temperature and moon phase on capture success of snowshoe hares; extremely low temperatures affected capture success but moon phase did not. Capture success can be improved by trapping snowshoe hares at temperatures above their lower critical temperature (Tlc). If abundance estimates are derived from mark‐recapture studies then effects of temperature should be included when modeling capture probabilities.
Unmasking the Cosmopolitan Tiger
Authors: Jalais Annu
Published: April 2008

The global 'cosmopolitan' tiger, as opposed to the local 'Sundarbans tiger', has become the rallying point for urbanites' concerns for wildlife protection globally. In this piece, I look at two different representations of tigers in recent history, one colonial and the other national. This so as to highlight how representations, even of wild animals, are ultimately linked to power. This leads me to argue how today's Western-dominated ideas about tigers (a view I call 'cosmopolitan') ultimately act to the detriment of 'other' tigers because these do not allow for an engagement with alternative ways of understanding animals and wildlife. Such images, I try to show using Descola's arguments about nature and understandings of it, in turn perpetrates the coercive and unequal relationship between, in this case, those who partake of the 'cosmopolitan' tiger view versus those who live with 'wild' tigers.
Both 'One' and 'Other': Environmental Cosmopolitanism and the Politics of Hybridity in Costa Rica
Authors: Johnson Mark , Clisby Suzanne
Published: April 2008

Cosmopolitans are frequently characterized as living and perceiving the world and their environment from a distance. Drawing on ethnographic work among a small group of Western migrants in Costa Rica, we complicate this portrayal in a number of ways. First, we demonstrate that these people think in similar kinds of ways as social theorists: they too are worried about living at a distance from place and are seeking what is, in their way of reckoning, a more engaged relationship with their surroundings. Second, however, we explore the social context and corollaries of these migrants' attempts to bring together a putatively "modern/cosmopolitan" way of relating to place and a "traditional/place-based" way of relating to surroundings. Specifically, we demonstrate how migrant claims to transcend the differences between "tradition" and "modernity" create new forms of social exclusion as they, both literally and figuratively, come to claim the place of "the other."
The Cosmopolitanism of Environmental Activists in Sri Lanka
Authors: Guneratne Arjun
Published: April 2008

This paper examines the emergence in Sri Lanka of transcultural thinking about environmental issues as well as the activism it engenders by examining the role of the Anglophone Sri Lankan elite as the chief protagonists historically of environmentalism in the country. It also examines one of Sri Lanka's leading NGOs, Environmental Foundation Ltd. (EFL) as an example of the activism of this class. EFL's perspective on environmental issues has its origins in the transformations wrought by colonialism in the country's class structure and in the introduction of European ideas of nature to the country's newly emergent middle-class. Modelled on the Natural Resources Defense Council of the United States, EFL was a new kind of environmental organization in Sri Lanka and a response to globalization and Sri Lanka's increasing integration into the global economy. Unlike the handful of environmental NGOS that existed in the late seventies, which were essentially pressure groups, EFL was conceived, on the model of NRDC, as a public interest law firm, and drew on international models to frame its arguments about the application of the law in the cause of environmental protection. This paper examines how these various factors—the social class of the activists and the processes of institution building—shaped a cosmopolitan environmental discourse in Sri Lanka whose roots lie in urban Sri Lankan middle class culture as it emerged and was transformed during colonial rule and in the various discourses of globalization that have been drawn on by Sri Lankan activists to craft their own arguments.
Hitting a moving target: evolution of a treatment paradigm for atypical meningiomas amid changing diagnostic criteria
Authors: Pearson Blake E. , Markert James M. , Fisher Winfield S. , Guthrie Barton L. , Fiveash John B. , Palmer Cheryl A. , Riley Kristen
Published: April 2008

Object

The World Health Organization (WHO) reclassified atypical meningiomas in 2000, creating a more clear and broadly accepted definition. In this paper, the authors evaluated the pathological and clinical transition period for atypical meningiomas according to the implementation of the new WHO grading system at their institution.

Methods

A total of 471 meningiomas occurring in 440 patients between 1994 and 2006 were retrospectively reviewed to determine changes in diagnostic rates, postoperative treatment trends, and early outcomes.

Results

Between 1994 and 2000, the incidence of the atypical meningiomas ranged from 0 to 3/year, or 4.4% of the meningiomas detected during the entire period. After 2002, the annual percentage of atypical meningiomas rose over a 2-year period, leveling off at between 32.7 and 35.5% between 2004 and 2006. The authors also found a recent trend toward increased use of adjuvant radiation therapy for incompletely resected atypical meningiomas. Prior to 2003, 18.7% were treated with this therapy; after 2003, 34.4% of lesions received this treatment. Incompletely resected tumors were treated with some form of radiation 76% of the time. In cases of complete resection, most patients were not given adjuvant therapy but were expectantly managed by close monitoring using serial imaging and by receiving immediate treatment for tumor recurrence. The overall recurrence rate for expectantly managed tumors was 9% over 28.2 months, and 75% of recurrences responded to delayed radiation therapy.

Conclusions

The authors documented a significant change in the proportion of meningiomas designated as atypical during a transition period from 2002 to 2004, and propose a conservative strategy for the use of radiation therapy in atypical meningiomas.
Radiation therapy and CyberKnife radiosurgery in the management of craniopharyngiomas
Authors: Lee Marco , Kalani M. Yashar S. , Cheshier Samuel , Gibbs Iris C. , Adler John R. , Chang Steven D.
Published: April 2008

Object

Many benign intracranial tumors are amenable to radiotherapy treatment including meningiomas, schwannomas, pituitary tumors, and craniopharyngiomas. The authors present their experience in the treatment of craniopharyngiomas in 16 patients using frameless CyberKnife stereotactic radiosurgery (SRS). The authors discuss the role of radiation therapy in the management of these tumors, and more specifically, the role of CyberKnife SRS.

Methods

Sixteen patients were treated for residual or recurrent craniopharyngioma between 2000 and 2007 with CyberKnife SRS at Stanford University Medical Center. All patients underwent magnetic resonance imaging and visual and neuroendocrine evaluations before and at regular intervals after SRS. A multisession treatment regimen and a nonisocentric treatment plan for each patient were used with a mean marginal dose of 21.6 Gy and a mean maximal dose of 29.9 Gy.

Results

There were adequate clinical data to assess outcomes in 11 of 16 patients. Evaluation of patients between 13 and 71 years of age (mean 34.5 years) with a mean follow-up period of 15.4 months revealed no deterioration in visual or neuroendocrine function. Tumor shrinkage was achieved in 7 of these 11 patients, and tumor control in another 3. One patient had cystic enlargement of the residual tumor.

Conclusions

The authors' early experience with the application of CyberKnife SRS to residual or recurrent craniopharyngiomas has been positive; control or shrinkage of the tumor was achieved in 91% of patients, with no visual or neuroendocrine complications. Longer-term follow-up with a larger group of patients is required to fully evaluate the safety and effectiveness of this treatment modality.
Evaluation of the role of Gamma Knife surgery in the treatment of craniopharyngiomas
Authors: Gopalan Rupa , Dassoulas Kasandra , Rainey Jessica , Sherman Jonathan H. , Sheehan Jason P.
Published: April 2008

✓ The management of craniopharyngioma involves balancing adequate reduction in tumor volume and prevention of recurrence while minimizing damage to delicate surrounding structures. Because of the lesion's proximity to the optic chiasm and its relationship to the hypothalamic–pituitary axis, morbidity rates following treatment can be high. Gamma Knife surgery (GKS) is now being considered as a viable method of providing tumor control while ensuring minimal side effects. The authors conducted a literature review of 10 studies in which GKS was used to treat craniopharyngioma; some lesions had been previously treated and some had not. The mean marginal dose ranged from 5 to 16.4 Gy (mean 12.3 Gy). Tumor control was achieved in 75% of cases overall and varied with tumor subtype (cystic, solid, mixed). Control was seen in 90% of solid, 80% of cystic, and 59% of mixed tumors. The overall morbidity rate resulting from radiosurgery was 4% and the overall mortality rate was 0.5%. These results suggest that GKS may provide a favorable benefit-to-risk profile for many patients with craniopharyngiomas.
Radiosurgery for hypothalamic hamartomas
Authors: Romanelli Pantaleo , Muacevic Alexander , Striano Salvatore
Published: April 2008

✓ Radiosurgery plays an important role in the treatment of refractory seizures induced by hypothalamic hamartomas (HHs). These lesions, deeply located and surrounded by a delicate vascular and neuronal network, are often associated with catastrophic epilepsy leading to progressive cognitive and behavioral deterioration. Surgical approaches include microsurgical resection, endoscopic resection or disconnection, radiofrequency lesioning, and interstitial brachytherapy. Radiosurgery is an emerging treatment modality for HHs, which provides excellent seizure outcomes and no lasting complications to date.
Repeat posterior fossa exploration for patients with persistent or recurrent idiopathic trigeminal neuralgia
Authors: Amador Nelly , Pollock Bruce E.
Published: April 2008

Object

Patients with trigeminal neuralgia (TN) and persistent or recurrent facial pain after microvascular decompression (MVD) typically undergo less invasive procedures in the hope of providing pain relief. The outcomes and risks of repeat posterior fossa exploration (PFE) for these patients are not clearly understood.

Methods

From September 2000 to November 2006, 29 patients (14 men, 15 women) underwent repeat PFE. The mean number of surgeries per patient at the time of repeat PFE was 3.2 (range 1–6). The mean follow-up duration after surgery was 33.7 months.

Results

Compression of the trigeminal nerve was noted in 24 patients (83%) by an artery (13 patients, 45%), vein (4 patients, 14%), or Teflon (7 patients, 24%). Four patients (14%) who underwent operations elsewhere had incorrect cranial nerves decompressed at their first surgery. Only MVD was performed in 18 patients (62%) and a partial nerve section (PNS) was performed in 11 patients (38%). An excellent facial pain outcome (no pain, no medications required) was achieved and maintained for 80% and 75% of patients at 1 and 3 years after surgery, respectively. Patients with Burchiel Type 1 TN were pain free without medications (91% at 1 year and 85% at 3 years) more frequently than patients with Burchiel Type 2 TN (27% at both 1 and 3 years; hazard ratio = 5.4, 95% confidence interval 1.4–21.1, p = 0.02). Fifteen patients (52%) had new or increased facial numbness. Two patients (7%) developed anesthesia dolorosa; both had undergone PNS. Two patients (7%) had hearing loss after surgery.

Conclusions

Repeat PFE for patients with idiopathic TN has facial pain outcomes that are comparable with both percutaneous needle-based techniques and stereotactic radiosurgery. Patients with persistent or recurrent TN should be considered for repeat PFE, especially if other less invasive surgeries have not relieved their facial pain.
Ventricular catheter trajectories from traditional shunt approaches: a morphometric study in adults with hydrocephalus
Authors: Lind Christopher R. P. , Tsai Amy M. C. , Law Andrew J. J. , Lau Hui , Muthiah Kavitha
Published: April 2008

Object

The purpose of this study was to compare the margins of error of different shunt catheter approaches to the lateral ventricle and assess surface anatomical aiming landmarks for free-hand ventricular catheter insertion in adult patients with hydrocephalus.

Methods

Four adults who had undergone stereotactic brain magnetic resonance (MR) imaging and had normal ventricles, and 7 prospectively recruited adult patients with acute hydrocephalus were selected for inclusion in this study. Reconstructed MR images obtained prior to surgical intervention were geometrically analyzed with regard to frontal, parietal, and parietooccipital (occipital) approaches in both hemispheres.

Results

The ventricular target zones were as follows: the frontal horn for frontal and occipital approaches, and the atrium/ posterior horn for parietal approaches. The range of possible angles for successful catheter insertion was smallest for the occipital approach (8° in the sagittal plane and 11° in the coronal plane), greater for parietal catheters (23 and 36°), and greatest for the frontal approach in models of hydrocephalic brains (42 and 30°; p < 0.001 for all comparisons except frontal vs parietal, which did not reach statistical significance). There was no single landmark for aiming occipital or parietal catheters that achieved ventricular target cannulation in every case. Success was achieved in only 86% of procedures using occipital trajectories and in 66% of those using parietal trajectories.

Conclusions

The occipital approach to ventricular catheter insertion provides the narrowest margin of error with regard to trajectory but has less aiming point variability than the parietal approach. The use of patient-specific stereotaxy rather than generic guides is required for totally reliable, first-pass ventricular catheterization via a posterior approach to shunt placement surgery in adults.
Cerebral oxygenation, vascular reactivity, and neurochemistry following decompressive craniectomy for severe traumatic brain injury
Authors: Ho Chi Long , Wang Chee Meng , Lee Kah Keow , Ng Ivan , Ang Beng Ti
Published: April 2008

Object

This study addresses the changes in brain oxygenation, cerebrovascular reactivity, and cerebral neurochemistry in patients following decompressive craniectomy for the control of elevated intracranial pressure (ICP) after severe traumatic brain injury (TBI).

Methods

Sixteen consecutive patients with isolated TBI and elevated ICP, who were refractory to maximal medical therapy, underwent decompressive craniectomy over a 1-year period. Thirteen patients were male and 3 were female. The mean age of the patients was 38 years and the median Glasgow Coma Scale score on admission was 5.

Results

Six months following TBI, 11 patients had a poor outcome (Group 1, Glasgow Outcome Scale [GOS] Score 1–3), whereas the remaining 5 patients had a favorable outcome (Group 2, GOS Score 4 or 5). Decompressive craniectomy resulted in a significant reduction (p < 0.001) in the mean ICP and cerebrovascular pressure reactivity index to autoregulatory values (< 0.3) in both groups of patients. There was a significant improvement in brain tissue oxygenation (PbtO2) in Group 2 patients from 3 to 17 mm Hg and an 85% reduction in episodes of cerebral ischemia. In addition, the durations of abnormal PbtO2 and biochemical indices were significantly reduced in Group 2 patients after decompressive craniectomy, but there was no improvement in the biochemical indices in Group 1 patients despite surgery.

Conclusions

Decompressive craniectomy, when used appropriately in protocol-driven intensive care regimens for the treatment of recalcitrant elevated ICP, is associated with a return of abnormal metabolic parameters to normal values in patients with eventually favorable outcomes.
Traumatic brain injury during Operation Iraqi Freedom: findings from the United States Navy–Marine Corps Combat Trauma Registry
Authors: Galarneau Michael R. , Woodruff Susan I. , Dye Judy L. , Mohrle Charlene R. , Wade Amber L.
Published: April 2008

Object

The purpose of this study was to characterize traumatic brain injuries (TBIs) among military personnel (primarily Marines) during the second phase of Operation Iraqi Freedom from early in the medical care chain of evacuation through Landstuhl Regional Medical Center, a Level 4 American hospital in Germany.

Methods

Data were obtained from the Navy–Marine Corps Combat Trauma Registry (CTR) and included both battle and nonbattle injuries. Follow-up of patients with TBI was conducted to examine the short-term medical and personnel-related effects of TBI among those surviving.

Results

Those injured in battle were more likely than those not injured in battle to have multiple TBI diagnoses, a greater number of all diagnoses, more severe TBIs, and to be medically evacuated. Intracranial injuries (for example, concussions) were the predominant type of TBI, although skull fractures and open head wounds were also seen. Improvised explosive devices were the most common cause of TBIs among battle injuries; blunt trauma and motor vehicle crashes were the most common causes among nonbattle injuries. Short-term follow-up of surviving patients with TBI indicated higher morbidity and medical utilization among the patients with more severe TBI, although mental conditions were higher among patients with milder TBI.

Conclusions

Data from the Navy–Marine Corps CTR provide useful information about combatants' TBIs identified early in the combat casualty process. Results may improve clinical care for those affected and suggest strategies for primary prevention. The CTR staff plans to conduct additional follow-up studies of this group of patients with TBI.
Phase II clinical trial of Wilms tumor 1 peptide vaccination for patients with recurrent glioblastoma multiforme
Authors: Izumoto Shuichi , Tsuboi Akihiro , Oka Yoshihiro , Suzuki Tsuyoshi , Hashiba Tetsuo , Kagawa Naoki , Hashimoto Naoya , Maruno Motohiko , Elisseeva Olga A. , Shirakata Toshiaki , Kawakami Manabu , Oji Yusuke , Nishida Sumiyuki , Ohno Satoshi , Kawase Ichiro , Hatazawa Jun , Nakatsuka Shin-ichi , Aozasa Katsuyuki , Morita Satoshi , Sakamoto Junichi , Sugiyama Haruo , Yoshimine Toshiki
Published: April 2008

Object

The object of this study was to investigate the safety and clinical responses of immunotherapy targeting the WT1 (Wilms tumor 1) gene product in patients with recurrent glioblastoma multiforme (GBM).

Methods

Twenty-one patients with WT1/HLA-A*2402–positive recurrent GBM were included in a Phase II clinical study of WT1 vaccine therapy. In all patients, the tumors were resistant to standard therapy. Patients received intra-dermal injections of an HLA-A*2402–restricted, modified 9-mer WT1 peptide every week for 12 weeks. Tumor size, which was obtained by measuring the contrast-enhanced area on magnetic resonance images, was determined every 4 weeks. The responses were analyzed according to Response Evaluation Criteria in Solid Tumors (RECIST) 12 weeks after the initial vaccination. Patients who achieved an effective response continued to be vaccinated until tumor progression occurred. Progression-free survival and overall survival after initial WT1 treatment were estimated.

Results

The protocol was well tolerated; only local erythema occurred at the WT1 vaccine injection site. The clinical responses were as follows: partial response in 2 patients, stable disease in 10 patients, and progressive disease in 9 patients. No patient had a complete response. The overall response rate (cases with complete or partial response) was 9.5%, and the disease control rate (cases with complete or partial response as well as those in which disease was stable) was 57.1%. The median progression-free survival (PFS) period was 20.0 weeks, and the 6-month (26-week) PFS rate was 33.3%.

Conclusions

Although a small uncontrolled nonrandomized trial, this study showed that WT1 vaccine therapy for patients with WT1/HLA-A*2402–positive recurrent GBM was safe and produced a clinical response. Based on these results, further clinical studies of WT1 vaccine therapy in patients with malignant glioma are warranted.
Craniocerebral penetrating injury caused by a spear gun through the mouth
Authors: Ban Leang Heng , Leone Marc , Visintini Pierre , Blasco Valery , Antonini François , Kaya Jean Marc , Alliez Bernard , Albanèse Jacques , Martin Claude
Published: April 2008

✓The authors report a case of a craniocerebral penetrating injury caused by the shaft of a spear gun. The entry point of the spear was located in the mouth without an obvious exit point. The authors first note the presentation of the patient, whose airway was obstructed by the shaft, and then discuss the surgical procedure, which was focused on removing the shaft in an anterograde direction because of an articulated wishbone located at the tip of the shaft.
Carpal tunnel syndrome: matching minimally invasive surgical techniques
Authors: Nazzi Vittoria , Franzini Angelo , Messina Giuseppe , Broggi Giovanni
Published: April 2008

✓In the past few years, several different minimally invasive surgical techniques have been proposed to decompress the median nerve at the wrist. Use of these techniques has become widespread due to fewer local complications, faster functional recovery, and reduced surgical time. In this paper the authors compare 3 different minimally invasive surgical techniques used at their institution in the past 13 years. Between January 1994 and January 2007, 891 patients underwent 1272 surgeries at the authors' institution for carpal tunnel syndrome (CTS), for which a minimally invasive technique was used. In 473 cases (Group A), the transillumination technique with a single wrist incision and a “carpalotome” (a modified Paine retinaculotome) was used; in 216 cases (Group B), transillumination was abandoned and a single linear wrist incision for access with the carpalotome was performed; and in 583 cases (Group C), the techniques were further modified by making a second incision in the palm using the carpalotome. All 3 groups of patients were homogeneous for age, sex, and duration of the symptomatology. In 90% of the patients in Group A, in 88% of those in Group B, and 99.8% of patients in Group C, complete remission of symptoms was obtained. Due to persistence of symptoms, 44 patients in Group A, 24 in Group B, and only 1 in Group C underwent a repeated operation with the open technique. The only surgical complication requiring repeated operation of the 1272 operations was a lesion of the primitive median artery (1 patient in Group C).

The technique of median nerve decompression at the wrist that was used for patients in Group C represents a valid alternative for treatment of CTS.
The evolution of the endonasal approach for craniopharyngiomas
Authors: Gardner Paul A. , Prevedello Daniel M. , Kassam Amin B. , Snyderman Carl H. , Carrau Ricardo L. , Mintz Arlan H.
Published: April 2008

✓Craniopharyngiomas have always been an extremely challenging type of tumor to treat. The transsphenoidal route has been used for resection of these lesions since its introduction. The authors present a historical review of the literature from the introduction of the endonasal route for resection of craniopharyngiomas until the present. Abandoned early due to technological limitations, this approach has been expanded both in its application and in its anatomical boundaries with subsequent progressive improvements in outcomes. This expansion has coincided with advances in visualization devices, imaging guidance techniques, and anatomical understanding. The progression from the use of headlights, to microscopy, to endoscopy and fluoroscopy, and finally to modern intraoperative magnetic resonance–guided techniques, combined with collaboration between otolaryngologists and neurosurgeons, has provided the framework for the development of current techniques for the resection of sellar and suprasellar craniopharyngiomas.
Toward reducing shunt placement rates in patients with myelomeningocele
Authors: Chakraborty Aabir , Crimmins Darach , Hayward Richard , Thompson Dominic
Published: April 2008

Object

The prevalence of shunt-dependent hydrocephalus in patients with myelomeningocele has been reported to be in the region of 85%, and shunt-related complications are a significant cause of morbidity and mortality in these patients. Since 1997 the authors have adopted a stringent policy with respect to shunt placement in patients with myelomeningocele, reserving this treatment for those with symptomatic hydrocephalus, severe ventricular dilation at the time of presentation, and/or unequivocal progressive ventriculomegaly after primary closure. They report their experience.

Methods

The authors reviewed all cases of myelomeningocele involving patients who presented to their institution over a 10-year period. They excluded cases in which the primary closure was carried out at another institution or in which there was not at least 12 months of clinical and imaging follow-up. Data regarding shunt insertion shunt-related complications, and clinical outcome were obtained from a review of the clinical records and analyzed.

Results

Fifty-four cases satisfied the inclusion criteria for this study. Shunt insertion was performed in 28 of these cases (51.9%).

Conclusions

Applying more stringent guidelines for shunt placement, permitting moderate ventricular dilation, and accepting some mild increase in ventricular size after myelomeningocele closure has resulted in a reduced rate of shunt placement compared with previous series. The rate is comparable to that reported following in utero closure of myelomeningocele.
Cerebrospinal fluid shunt infections in children over a 13-year period: anaerobic cultures and comparison of clinical signs of infection with Propionibacterium acnes and with other bacteria
Authors: Arnell Kai , Cesarini Kristina , Lagerqvist-Widh Angela , Wester Tomas , Sjölin Jan
Published: April 2008

Object

Shunt infections represent a major problem with risk for sequelae and even death. The aim in this retrospective study was to analyze the incidence, origin, and clinical presentation of shunt infections, with special reference to the results of cultures for anaerobic organisms performed in addition to the usual tests, to prolonged incubation times, and to infections caused by Propionibacterium acnes.

Methods

The medical records of 237 hydrocephalic children (age range 0–15 years) in whom operations were performed by a pediatric surgeon at Uppsala University Hospital during a 13-year period were reviewed.

Results

Thirty-four verified or suspected intraventricular shunt infections and 5 distal catheter infections occurred after 474 operations. Skin bacteria, such as coagulase-negative staphylococci ([CoNS], 19 patients), Staphylococcus aureus (7 patients), and P. acnes (6 patients) predominated. The addition of anaerobic cultures and prolonged incubation times increased the verification of shunt infection by more than one third. Children with P. acnes infection were significantly older, had a lower body temperature, fewer cerebrospinal fluid (CSF) leukocytes, a higher CSF/blood glucose ratio, more distal catheter infections, and other sources of infection. Four had an abdominal pseudocyst. Children < 1 year of age and infected with CoNS were more affected than older children with systemic and local symptoms. In children with distal catheter infection and growth of propionibacteria at the time of the distal catheter and valve replacement, no follow-up antibiotic treatment was necessary.

Conclusions

Addition of anaerobic cultures and prolonged incubation times led to an increase in the detection of shunt infections. Infections caused by propionibacteria often result in mild symptoms that may be overlooked if adequate anaerobic cultures are not obtained.
Chemotherapy administration directly into the fourth ventricle in a new piglet model
Authors: Sandberg David I. , Crandall Kenneth M. , Petito Carol K. , Padgett Kyle R. , Landrum John , Babino Darwin , He Danshe , Solano Juan , Gonzalez-Brito Manuel , Kuluz John W.
Published: April 2008

Object

The authors hypothesized that chemotherapy infusions directly into the fourth ventricle may potentially play a role in treating malignant posterior fossa tumors. In this study the safety and pharmacokinetics of etoposide administration into the fourth ventricle was tested using an indwelling catheter in piglets.

Methods

A closed-tip silicone lumbar drain catheter was inserted into the fourth ventricle via a posterior fossa craniectomy and 5 daily infusions of etoposide (0.5 mg in 5 animals) or normal saline (in 2 animals) were instilled. Piglets (10–18 kg, 2–3 months of age) underwent daily neurological examinations and 4.7-T magnetic resonance (MR) imaging after the final infusion and were then killed for postmortem examination. Pharmacokinetics were studied using reversed-phase high-performance liquid chromatography on cerebrospinal fluid (CSF) samples at 0.25, 1, 2, 4, 8, 12, and 24 hours after etoposide infusion. Peak and trough CSF etoposide levels were measured for each subsequent infusion. Serum etoposide levels were obtained at 2 and 4 hours after infusion.

Results

All piglets remained neurologically intact, and MR images demonstrated catheter placement within the fourth ventricle without signal changes in the brainstem or cerebellum. Serum etoposide was absent at 2 and 4 hours after intraventricular infusions. When adequate samples could be obtained for analysis, CSF etoposide levels peaked 15 minutes after infusion and progressively decreased. Cytotoxic levels (> 0.1 μg/ml) were maintained for 5 consecutive peak and trough measurements with 1 exception. Etoposide-related neuropathology included moderate-to-severe T-lymphocytic meningitis and fourth and lateral ventricular choroid plexitis with associated subependymal inflammation.

Conclusions

Etoposide can be infused directly into the fourth ventricle without clinical or imaging evidence of damage. Cytotoxic CSF etoposide levels can be maintained for 24 hours with a single daily infusion into the fourth ventricle using an indwelling catheter. Intraventricular etoposide elicits an inflammatory response, the long-term effects of which are as yet undetermined.
Delayed presentation and conservative management of an odontoid basilar synchondrosis fracture in a child
Authors: Crandall Kenneth M. , Pacheco-Jacome Esperanza , Sandberg David I.
Published: April 2008

✓ The authors report the case of a 3-year-old boy who presented with neck pain after falling from a low height and who was discharged from the emergency department after imaging studies were noted to be normal. He presented again 2 months later with continued neck pain, and repeated imaging demonstrated a fracture of the odontoid basilar synchondrosis that had not been shown on the initial studies. Based on the normal alignment of his spine and evidence of early bone fusion at the time of his second presentation, he underwent cervical orthosis therapy only. To the authors' knowledge, this is the first reported case of an odontoid synchondrosis fracture in which computed tomography scans were normal at presentation.