bluuebunny/crossref_metadata_2025 huggingface dataset:
Local structure and defects in ultrahigh-temperature materials of borosilicon carbonitride
Authors: Yamamoto Kazuhiro , Tsuganezawa Naoya , Makimura Shin-ichi , Sawa Daigo , Nakahigashi Shin-ichi , Kojima Kazuo , Hasegawa Yoshio
Published: June 2008

We have investigated structural changes of amorphous borosilicon carbonitride materials with atomic ratios of B/Si/C of 2/3/6 and 4/3/6 calcined at several temperatures. The boron K-edge x-ray absorption spectra showed that the structures of both hexagonal boron nitride ([BN3] unit) with nitrogen-void defects ([BN2] and [BN1] units) and boron oxide existed in the samples, and the relative peak intensity due to the [BN3] unit became stronger by increasing the calcined temperature. It is thought that the well-developed B–N chain and the borosilicate glass coating lead to the high resistance to oxidation at high temperature. X-ray diffraction and infrared measurements followed the x-ray absorption near-edge spectroscopy findings.
Survey of Community-Based Programs Serving U.S. Families With Huntington’s Disease: Perceived Barriers and Facilitators in the Residential Placement Process
Authors: Lechich Anthony J. , Lovecky Deborah , Moskowitz Carol , Montas Sybil , Duckett Ayana , Pae Anne , Knoblauch Kathy , Saks David , Toliver Dorothy , Fogarty Eileen , Pollard James
Published: June 2008

This article describes the contours of the residential care placement experience for social service staff, health care providers, and their client families of patients with Huntington’s disease. The purpose of this study was to determine the factors, conditions, and barriers encountered by outpatient clinical staff and families in the transition to skilled nursing care. A Long-Term Care Contact Survey was developed to (a) gather information about long-term care referral sites; (b) determine the factors considered in choosing a facility; (c) describe the factors that hindered the transition to long-term care; (d) describe conditions prior to institutionalization; and (e) determine research interest. The study found that large cohorts of patients with Huntington’s disease in residential care are scarce. A lack of confidence in the available options suggests the need for increased support for educational and social services to facility staff. Speech/swallowing therapy and physical therapy as placement facilitators reflect salient issues of latter stages of the disease, implicating funding support needs. Families facing this transition require long-term guidance for financial, caregiving, and psychosocial issues.
Too Sick to Work, Too Soon for Medicare: The Human Cost of the 2-Year Medicare Waiting Period for Americans With Disabilities
Authors: Hayes Robert M. , Beebe Deane , Kreamer Heidi
Published: June 2008

In the United States, nearly 7 million people under age 65 qualify for Medicare due to severe and permanent disabilities. However, these individuals must wait 2 years after they are deemed eligible for Social Security Disability Insurance to receive this coverage. As a result, there are as many as 1.5 million men and women who are too disabled to return to work but who must wait to receive Medicare coverage for their health care needs. Nearly 39% are uninsured for at least some of this time, and 26% have no insurance throughout the waiting period. This article tells the stories of three individuals struggling to survive the 24-month waiting period. These real-life stories expose the financial hardship, pain, and suffering caused by the waiting period and provide evidence of the need for the swift enactment of legislation to eliminate the waiting period. In this article, these individuals give their accounts of what it means to become too sick or disabled to work, and to learn that it is too soon to get health care coverage through Medicare. In all cases, we have tried to stay as close as possible to the language and the spirit of the participants’ stories.
Oxidative mutagenicity of polar fractions from polycyclic aromatic hydrocarbon–contaminated soils
Authors: Park Joanna , Ball Louise M , Richardson Stephen D , Zhu Hong-Bo , Aitken Michael D
Published: June 2008

Soils at hazardous waste sites contain complex mixtures of chemicals and often are difficult to characterize in terms of risk to human and ecological health. Over time, biogeochemical processes can decrease the apparent concentrations of pollutants but also can lead to accumulation of new products for which toxicity and behavior in the environment are largely unknown. A bioassay-directed fractionation technique was used to assess the contribution of redox-active bacterial metabolites to the toxicity of soil contaminated with polycyclic aromatic hydrocarbons (PAHs). A reverse mutation assay with Escherichia coli WP2 uvrA/pKM101 (IC188) and E. coli WP2 uvrA oxyR/pKM101 (IC203) was used to screen fractions for genotoxicity. Strain IC203 carries the ΔoxyR30 mutation, which prevents the expression of antioxidant proteins in response to oxidative stress and increases its reversion by compounds that generate reactive oxygen species (ROS). Polar fractions of PAH-contaminated soil extracts were mutagenic to strain IC203 but not to strain IC188, suggesting the involvement of ROS in genotoxicity. Genotoxic potencies ranged from 300 to 1,700 revertants per milligram of fraction. Catalase was able to decrease IC203 reversion, implicating the involvement of hydrogen peroxide as a key ROS. Oxidized PAH compounds, including quinones, were identified in the mutagenic fractions but were not by themselves mutagenic. Deasphalted whole extracts and recombined fractions were not mutagenic, indicating that interactions between compounds in different fractions can mitigate genotoxicity.
Uncertainty of water type–specific hazardous copper concentrations derived with biotic ligand models
Authors: Vijver Martina G , de Koning Arjan , Peijnenburg Willie J.G.M
Published: June 2008

One of the aims of the Water Framework Directive is to derive Europe-wide environmental quality standards that are scientifically based and protective of surface waters. Accounting for water type–specific bioavailability corrections presents challenges and opportunities for metals research. In this study, we present generally applicable approaches for tiered risk assessment of chemicals for prospective use. The objective of the present study was to derive water type–specific dissolved copper criteria for Dutch surface waters. The intent was to show the utility of accounting for bioavailability by using biotic ligand models (BLMs) and two different ways of extrapolating these BLMs in order to obtain reliable bioavailability-corrected species sensitivity distributions. Water type–specific criteria estimations were generated for six different water quality conditions. Average hazard concentrations as calculated using the BLMs and the two alternate normalization scenarios varied significantly among the different water types, from 5.6 to 73.6 μg/L. Water types defined as large rivers, sandy springs, and acid ponds were most sensitive for Cu. Streams and brooks had the highest hazard concentrations. The two different options examined for toxicity data normalization did impact the calculated hazard concentrations for each water type.
Vascular foramina of the metacarpophalangeal sesamoid bones of Greyhounds and their relationship to sesamoid disease
Authors: Daniel Alison , Read Richard A. , Cake Martin A.
Published: June 2008

Objective—To apply a novel technique and use the number and size (diameter and mean area) of vascular foramina to estimate potential blood supply in the metacarpophalangeal bones of dogs.

Animals—28 Greyhounds.

Procedures—The forelimb sesamoid bones of 23 dogs were obtained after dogs were euthanized. Bones were isolated and examined by scanning electron microscopy. The number, diameter, and area of vascular foramina were determined by image analysis. Arterial distribution was assessed by use of resin injection in the sesamoid bones of 5 additional dogs.

Results—Sesamoids 2 and 7 had significantly fewer foramina (mean ± SE, 38.9 ± 2.5) and lower total foramen area (0.55 ± 0.04 mm2), compared with values for other sesamoids (70.4 ± 3.3 foramina and 1.43 ± 0.06 mm2, respectively). Mean area and diameter of foramina of sesamoids 2 and 7 were also smaller in some regions. Comparison of the foramen distribution in dogs with sesamoid disease and clinically normal dogs revealed that for sesamoids 2 and 7, intact sesamoids from dogs with sesamoid disease had a significantly lower total foramen area (20 sesamoids from 9 dogs, 0.45 ± 0.04 mm2), compared with sesamoids in clinically normal dogs (59 sesamoids from 14 dogs, 0.58 ± 0.03 mm2). However, for sesamoids other than 2 and 7, dogs with sesamoid disease had a significantly greater foramen area.

Conclusions and Clinical Relevance—The restriction of vascular foramina in sesamoids 2 and 7 appeared to mirror the disease distribution and disease risk for specific dogs.
Effects of a peripheral α2 adrenergic-receptor antagonist on the hemodynamic changes induced by medetomidine administration in conscious dogs
Authors: Enouri Saad S. , Kerr Carolyn L. , McDonell Wayne N. , O'Sullivan M. Lynne , Neto Francisco J. Teixeira
Published: June 2008

Objective—To evaluate the effects of administration of a peripheral α2-adrenergic receptor antagonist (L-659,066), with and without concurrent administration of glycopyrrolate, on cardiopulmonary effects of medetomidine administration in dogs.

Animals—6 healthy adult dogs.

Procedures—Dogs received saline (0.9% NaCl) solution (saline group), L-659,066 (group L), or L-659,066 with glycopyrrolate (group LG). These pretreatments were followed 10 minutes later by administration of medetomidine in a randomized crossover study. Hemodynamic measurements and arterial and mixed-venous blood samples for blood gas analysis were obtained prior to pretreatment, 5 minutes after pretreatment, and after medetomidine administration at intervals up to 60 minutes.

Results—After pretreatment in the L and LG groups, heart rate, cardiac index, and partial pressure of oxygen in mixed-venous blood (PvO2) values were higher than those in the saline group. After medetomidine administration, heart rate, cardiac index, and PvO2 were higher and systemic vascular resistance, mean arterial blood pressure, and central venous pressure were lower in the L and LG groups than in the saline group. When the L and LG groups were compared, heart rate was greater at 5 minutes after medetomidine administration, mean arterial blood pressure was greater at 5 and 15 minutes after medetomidine administration, and central venous pressure was lower during the 60-minute period after medetomidine administration in the LG group.

Conclusions and Clinical Relevance—Administration of L-659,066 prior to administration of medetomidine reduced medetomidine-induced cardiovascular changes in healthy dogs. No advantage was detected with concurrent administration of L-659,066 and glycopyrrolate.
Assessment of vitamin E concentrations in serum and cerebrospinal fluid of horses following oral administration of vitamin E
Authors: Higgins Jamie K. , Puschner Birgit , Kass Philip H. , Pusterla Nicola
Published: June 2008

Objective—To determine concentrations of α-tocopherol in serum and CSF of healthy horses following administration of supplemental vitamin E in feed.

Animals—10 healthy adult horses.

Procedures—Horses were allocated to receive supplemental d-α-tocopherol (1,000 U/d [group A; n = 5] or 10,000 U/d [group B; 5]) in feed for 10 days. Blood samples were collected before (baseline), during, and at intervals for 10 days after discontinuation of vitamin E administration for assessment of serum α-tocopherol concentration. Cerebrospinal fluid samples were collected prior to and 24 hours after cessation of vitamin E administration. α-Tocopherol concentrations in serum and CSF samples were analyzed via high-performance liquid chromatography; changes in those values during the treatment period were compared between groups, and the relationship of serum and CSF α-tocopherol concentrations was evaluated.

Results—In both groups, serum α-tocopherol concentration increased significantly from baseline during vitamin E administration; values in group B were significantly greater than those in group A during and after treatment. At the end of vitamin E administration, CSF α-tocopherol concentration was not significantly greater than the baseline value in either group; however, the increase in CSF concentration was significant when the group data were combined and analyzed. Serum and CSF α-tocopherol concentrations were significantly correlated at baseline for all horses, but were not strongly correlated after 10 days of vitamin E administration.

Conclusions and Clinical Relevance—In healthy horses, daily oral administration of supplemental vitamin E in feed resulted in increases in serum and CSF α-tocopherol concentrations.
Effects of nuclear factor-κB on regulation of cytokine expression and apoptosis in bovine monocytes exposed to Mycobacterium avium subsp paratuberculosis
Authors: Weiss Douglas J. , Souza Cleverson D. , Evanson Oral A.
Published: June 2008

Objective—To evaluate the role of the nuclear factor-κB (NF-κB) in the response of bovine monocytes to exposure to Mycobacterium avium subsp paratuberculosis (MAP).

Sample Population—Monocytes from healthy adult Holstein cows that were known to be negative for MAP infection.

Procedures—Monocytes were incubated with MAP organisms with or without a specific inhibitor of the NF-κB pathway (pyrrolidine dithiocarbamate), and activation of the NF-κB pathway was detected by use of an electrophorectic mobility shift assay. The capacities of monocytes to express tumor necrosis factor (TNF)-α, interleukin (IL)-10, and IL-12; to acidify phagosomes; to phagocytize and kill MAP organisms; and to undergo apoptosis were evaluated.

Results—Addition of MAP organisms to monocytes activated the NF-κB pathway as indicated by increased NF-κB–DNA binding. Addition of pyrrolidine dithiocarbamate prevented nuclear translocation of NF-κB, decreased expression of TNF-α and IL-10, and increased IL-12 expression. Treatment of MAP-exposed monocytes with pyrrolidine dithiocarbamate increased the rate of apoptosis but failed to alter phagosome acidification, organism uptake, or organism killing by those cells.

Conclusions and Clinical Relevance—Results indicated that NF-κB rapidly translocated to the nucleus after exposure of bovine monocytes to MAP organisms. These data suggest that NF-κB is involved in initiation of inflammatory cytokine transcription and inhibition of apoptosis but that it is not directly involved in phagosome acidification or organism killing.
Insulin sensitivity in Belgian horses with polysaccharide storage myopathy
Authors: Firshman Anna M. , Valberg Stephanie J. , Baird John D. , Hunt Luanne , DiMauro Salvatore
Published: June 2008

Objective—To determine insulin sensitivity, proportions of muscle fiber types, and activities of glycogenolytic and glycolytic enzymes in Belgians with and without polysaccharide storage myopathy (PSSM).

Animals—10 Quarter Horses (QHs) and 103 Belgians in which PSSM status had been determined.

Procedures—To determine insulin sensitivity, a hyperinsulinemic euglycemic clamp (HEC) technique was used in 5 Belgians with PSSM and 5 Belgians without PSSM. Insulin was infused IV at 3 mU/min/kg for 3 hours, and concentrations of blood glucose and plasma insulin were determined throughout. An IV infusion of glucose was administered to maintain blood glucose concentration at 100 mg/dL. Activities of glycogenolytic and glycolytic enzymes were assessed in snap-frozen biopsy specimens of gluteus medius muscle obtained from 4 Belgians with PSSM and 5 Belgians without PSSM. Percentages of type 1, 2a, and 2b muscle fibers were determined via evaluation of ≥ 250 muscle fibers in biopsy specimens obtained from each Belgian used in the aforementioned studies and from 10 QHs (5 with PSSM and 5 without PSSM).

Results—Belgians with and without PSSM were not significantly different with respect to whole-body insulin sensitivity, muscle activities of glycogenolytic and glycolytic enzymes, or proportions of muscle fiber types. However, Belgians had an increased proportion of type 2a and decreased proportion of type 2b muscle fibers, compared with proportions in QHs, regardless of PSSM status.

Conclusions and Clinical Relevance—PSSM in Belgians may be attributable to excessive glycogen synthesis rather than decreased glycogen utilization or enhanced glucose uptake into muscle cells.
Comparison of 2-step laparoscopy-guided abomasopexy versus omentopexy via right flank laparotomy for the treatment of dairy cows with left displacement of the abomasum in on-farm settings
Authors: Roy Jean-Philippe , Harvey Denis , Bélanger Anne-Marie , Buczinski Sébastien
Published: June 2008

Objective—To compare characteristics and results of 2-step laparoscopy-guided abomasopexy versus omentopexy via laparotomy in the right paralumbar fossa for the treatment of dairy cows with a left displaced abomasum (LDA).

Design—Prospective clinical trial.

Animals—253 dairy cows with an LDA.

Procedures—All cows that were treated with omentopexy (n = 101) or 2-step laparoscopy-guided abomasopexy (152) from July 2005 through December 2006 were included. Presurgical, perisurgical, and postsurgical information was recorded by attending veterinarians. Producers were interviewed by telephone 7 and 60 days after surgery regarding the response of cows to surgery. Characteristics of and responses to the 2 surgical techniques were compared.

Results—At 7 days after surgery, the 2 groups of cows were not significantly different with respect to appetite, comfort, and milk yield; at 60 days after surgery, groups were similar with respect to milk yield, cull rates, and risk of relapse of LDA. Antimicrobial treatment in response to postsurgical pyrexia was necessary in only 20.4% (31/152) of cows that were treated with 2-step laparoscopy-guided abomasopexy. Mean duration (preparation and surgery) of 2-step laparoscopy-guided abomasopexy was significantly less than that of omentopexy (36 vs 74 minutes, respectively).

Conclusions and Clinical Relevance—Results of 2-step laparoscopy-guided abomasopexy and omentopexy via laparotomy in the right paralumbar fossa were not significantly different. Compared with omentopexy, laparoscopy-guided abomasopexy was performed more quickly and required postsurgical administration of antimicrobials less frequently. Although these factors may be of economic consequence to veterinarians and producers, other aspects must also be considered when choosing between techniques.
Achieving Excellence in Teacher Workforce and Equity in Learning Opportunities in South Korea
Authors: Kang Nam-Hwa , Hong Miyoung
Published: June 2008

Akiba, LeTendre, and Scribner (2007) identified two problems with mathematics education in the United States: (a) a shortage of qualified mathematics teachers and (b) unequal access to those teachers by students of high and low socioeconomic status. Akiba et al. called for further research on how South Korea and other countries have achieved excellence in their teacher workforces and equity in access to qualified teachers. They also called for research on what mediates the relationship between opportunity and achievement gaps. In response, the authors of this article describe pertinent South Korean educational contexts and policies. To ensure teacher quality in the United States, the authors propose establishing teaching as a professional occupation by offering competitive salaries, improving working conditions, and increasing teachers’ out-of-class time for planning and professional development. As a way to close the achievement gap, they recommend that accessible supplementary learning opportunities be provided for students who lack family and community resources.
Reporting Practices in Quantitative Teacher Education Research: One Look at the Evidence Cited in the AERA Panel Report
Authors: Zientek Linda Reichwein , Capraro Mary Margaret , Capraro Robert M.
Published: June 2008

The authors of this article examine the analytic and reporting features of research articles cited in Studying Teacher Education: The Report of the AERA Panel on Research and Teacher Education ( Cochran-Smith & Zeichner, 2005b ) that used quantitative reporting practices. Their purpose was to help to identify reporting practices that can be improved to further the creation of the best possible evidence base for teacher education. Their findings indicate that many study reports lack (a) effect sizes, (b) confidence intervals, and (c) reliability and validity coefficients. One possible solution is for journal editors to emphasize clearly the expectations established in Standards for Reporting on Empirical Social Science Research in AERA Publications ( AERA, 2006 ).
Trends in the surface vegetation dynamics of the national parks of Spain as observed by satellite sensors
Authors: Alcaraz‐Segura Domingo , Cabello Javier , Paruelo José M. , Delibes Miguel
Published: June 2008

Questions: What are the current dynamics, as observed by synoptic sensors, of surface vegetation in Spanish protected areas? Are these areas and their vegetation types uniformly affected by the increase in vegetation greenness detected throughout Europe?

Location: Iberian National Parks of Spain.

Methods: We used the normalized difference vegetation index (NDVI) from global inventory modeling and mapping studies (GIMMS) advanced very high resolution radiometer (AVHRR) dataset to monitor surface vegetation. NDVI is a surrogate for the photosynthetically active radiation absorbed by vegetation (fAPAR). This functional attribute has a short‐time response to disturbances, is connected to ecosystem services and can be monitored through remote sensing. First, we provide a baseline description of the NDVI dynamics in the parks and analysed its temporal trends (1981–2003). Then, we evaluated the relationships of the seasonal dynamics and interannual trends with the climate conditions, vegetation types and conservation histories of the parks.

Results: The parks showed two patterns of NDVI dynamics corresponding to Mediterranean and Eurosiberian regions. Most parks showed areas with positive NDVI trends that tended to have higher proportions of Mediterranean coniferous and mixed forests, oro‐Mediterranean scrublands, heathlands, maquis and garrigues. Negative trends were scarce and associated with marshes and Alpine coniferous forests. The lack of a common response in all parks was related to their different environmental conditions, management, and conservation histories. Conclusions: National parks are changing in the short term but not uniformly. This study represents a basis for the incorporation of functional attributes of ecosystems in the management and monitoring of protected areas in the face of global change.
Operative intracranial infection following craniotomy
Authors: Dashti Shervin R. , Baharvahdat Humain , Spetzler Robert F. , Sauvageau Eric , Chang Steven W. , Stiefel Michael F. , Park Min S. , Bambakidis Nicholas C.
Published: June 2008

Object

Postoperative infection after cranial surgery is a serious complication that requires immediate recognition and treatment. In certain cases such as postoperative meningitis, the patient can be treated with antibiotics only. In cases that involve a bone flap infection, subdural empyema, or cerebral abscess, however, reoperation is often needed. There has been significant disagreement regarding the incidence of postoperative central nervous system (CNS) infections following cranial surgery. In this paper the authors' goal was to perform a retrospective review of the incidence of CNS infection after cranial surgery at their institution. They focused their review on those patients who required repeated surgery to treat the infection.

Methods

The authors reviewed the medical records and imaging studies in all patients who underwent a craniotomy or stereotactic drainage for CNS infection over the past 10 years. Subgroup analysis was then performed in patients whose infection was a result of a previous cranial operation to determine the incidence, factors associated with infection, and the type of infectious organism. Patients treated nonoperatively (that is, those who received intravenous antibiotics for postoperative meningitis or cellulitis) were not included. Patients treated for wound infection without intracranial pus were also not included.

Results

During the study period from January 1997 through December 2007, ~ 16,540 cranial surgeries were performed by 25 neurosurgeons. These included elective as well as emergency and trauma cases. Of these cases 82 (0.5%) were performed to treat postoperative infection in 50 patients. All 50 patients underwent their original surgery at the authors' institution. The median age was 51 years (range 2–74 years). There were 26 male and 24 female patients.

The most common offending organism was methicillin-sensitive Staphylococcus aureus, which was found in 10 of 50 patients. Gram-negative rods were found in 15 patients. Multiple organisms were identified in specimens obtained in 5 patients. Six patients had negative cultures. Most craniotomies leading to subsequent infection were performed for tumors or other mass lesions (23 of 50 patients), followed by craniotomies for hemorrhage and vascular lesions. Almost half of the patients underwent > 1 cranial operation before presenting with infection.

Conclusions

Postoperative infection after cranial surgery is an important phenomenon that needs immediate recognition. Even with strict adherence to sterile techniques and administration of antibiotic prophylaxis, a small percentage of these patients will develop an infection severe enough to require reoperation.
Cerebral hydatid cysts: technique and pitfalls of surgical management
Authors: Izci Yusuf , Tüzün Yusuf , Seçer Halil Ibrahim , Gönül Engin
Published: June 2008

Object

Hydatid cysts are rare, but most often they occur in the liver and lungs. Cerebral manifestation is very rare, and surgery is the main treatment. The goal of surgery is to remove the cysts in toto without rupture. The aim of this study was to investigate the surgical technique of removing cerebral hydatid cysts and to show the possible pitfalls of surgery.

Methods

This study included 17 patients who underwent surgery for an intracranial hydatid cyst. The Dowling technique was used in all patients. This technique is based on the large cranial opening, careful handling, meticulous cortical dissection, and removal of the cyst by hydrostatic assistance.

Results

The hydatid cysts were removed unruptured in 88% of the cases. The cysts ruptured intraoperatively in 2 patients, and the ventricular system was opened in 1 of them. Anaphylactic reaction or chemical meningitis did not occur, but recurrence and spinal seeding were observed in the follow-up of these patients. The thin cyst wall, periventricular locations, and microadhesions to the surrounding brain tissue were the main surgical problems. None of the patients died after the surgery.

Conclusions

Although this technique seems safe and easy, there are some pitfalls concerning the cyst location and surgical approach. Successful management requires a flexible therapeutic strategy and meticulous dissection by an experienced surgeon.
Pyogenic brain abscess
Authors: Erdoğan Ersin , Cansever Tufan
Published: June 2008

✓ Brain abscesses have been one of the most challenging lesions, both for surgeons and internists. From the beginning of the computed tomography (CT) era, the diagnosis and treatment of these entities have become easier and less invasive. The outcomes have become better with the improvement of diagnostic techniques, neurosurgery, and broad-spectrum antibiotics. Atypical bacterial abscesses are more often due to chemotherapy usage in oncology, long life expectancy in patients with human immunodeficiency virus (HIV) infection, and immunosuppression in conjunction with organ transplantation. Surgical treatment options showed no significant difference with respect to mortality levels, but lower morbidity rates were achieved with stereotactically guided aspiration. Decompression with stereotactically guided aspiration, antibiotic therapy based on results of pus culture, and repeated aspirations if indicated from results of periodic CT follow-up scans seem to be the most appropriate treatment modality for brain abscesses. Immunosuppression and comorbidities, initial neurological status, and intraventricular rupture were significant factors influencing the outcomes of patients. The pitfalls and evolution in the diagnosis and treatment of brain abscesses are discussed in this study.
Brain abscess: analysis of results in a series of 51 patients with a combined surgical and medical approach during an 11-year period
Authors: Çavuşoglu Halit , Kaya Ramazan Alper , Türkmenoglu Osman Nuri , Çolak Ibrahim , Aydin Yunus
Published: June 2008

Object

In this study the authors' goal was to present the clinical and imaging results of the combined surgical and medical treatment of intracranial abscesses.

Methods

The authors retrospectively analyzed the data in 51 patients with intracranial abscesses who underwent surgery between January 1997 and November 2007. Patients were treated with aspiration through a single bur hole, total resection with open craniotomy, or image-guided stereotactic aspiration. Computed tomography or magnetic resonance imaging was performed ~ 24 hours after surgery to evaluate the size of the abscess and almost weekly during follow-up until the abscess and/or cerebral edema was reduced. Clinical results were analyzed using modified Rankin Scale (mRS) scores.

Results

There were 36 male and 15 female patients, and their ages ranged from 14 months to 58 years (mean 29 years). Adjacent localized cranial infection was the most common predisposing factor in 31 patients (61%). Thirty-two patients were treated by repeated aspiration via a single bur hole. Streptococcus and Staphylococcus species were isolated most frequently. No statistically significiant difference between causative organisms and clinical outcome was identified (p > 0.05). Assessment of overall 1-year clinical outcomes was favorable (mRS Scores 0–2) in 76.5% of patients (39 of 51 patients). The initial neurological condition was strongly correlated with the clinical outcome (p < 0.001).

Conclusions

A combination of surgical aspiration or removal of all abscesses > 2.5 cm in diameter, a 6-week or longer course of intravenous antibiotics, and weekly neuroimaging should yield cure rates of > 90% in patients with intracranial abscesses.
Wall enhancement, edema, and hydrocephalus after endovascular coil occlusion of intradural cerebral aneurysms
Authors: Fanning Noel F. , Willinsky Robert A. , terBrugge Karel G.
Published: June 2008

Object

Symptomatic local inflammation, aseptic meningitis, and hydrocephalus are reported in a group of patients treated with second generation/modified platinum coils. The purpose of this study was to define the frequency and determinants of magnetic resonance (MR) imaging findings of aneurysm wall enhancement, perianeurysmal edema, and hydrocephalus in a cohort of coil-embolized intradural cerebral aneurysms treated with bare platinum or modified platinum coils (Matrix or HydroCoils).

Methods

The authors retrospectively reviewed 359 Gd-enhanced MR follow-up studies of 181 treated aneurysms (125 ruptured) for mural enhancement. Univariate and multivariate logistic regression analyses were used to define mural enhancement associations with demographic, clinical, angiographic, treatment, and follow-up data. Embolization-related edema and hydrocephalus were defined in 95 MR imaging studies of 56 unruptured aneurysms.

Results

Asymptomatic wall enhancement was observed in lesions treated with all coil types, occurring in 21 (18.6%) of 113 bare platinum coil–treated aneurysms. Independent associations were HydroCoil treatment (odds ratio [OR] 9.75, 95% confidence interval [CI] 3.45–30.75) and increasing aneurysm size (OR 3.58, 95% CI 1.99–6.95). Five (8.9%) unruptured aneurysms had asymptomatic de novo edema, and 3 (5.3%) demonstrated hydrocephalus; all had been treated with HydroCoils. Hydrocephalus presentation was delayed (8–31 months) and symptomatic in 2 patients.

Conclusions

Asymptomatic aneurysm wall enhancement occurred in 18.6% of embolizations performed with bare platinum coils, and probably represents a normal healing response. Perimural edema and hydrocephalus were observed only in patients treated with HydroCoils, but have been reported in patients treated with other modified platinum coils. These symptoms appear to represent an exaggerated inflammatory response during aneurysm healing. Increased vigilance for delayed hydrocephalus is required. Judicious clinical use of modified platinum coils is warranted until results of randomized trials are published.
Use of the sole stenting technique for the management of aneurysms in the posterior circulation in a prospective series of 20 patients
Authors: Zenteno Marco Antonio , Santos-Franco Jorge Arturo , Freitas-Modenesi Jose Maria , Gómez Camilo , Murillo-Bonilla Luis , Aburto-Murrieta Yolanda , Díaz-Romero Ricardo , Nathal Edgar , Gómez-Llata Sergio , Lee Angel
Published: June 2008

Object

The use of intracranial stents in stent-assisted coil embolization is now a current neurosurgical practice worldwide. The clinical utility of these stents in the sole stenting (SS) technique, however, has not been thoroughly described, and the published reports of this experience are scarce. This study was designed to evaluate SS treatment of dissecting and nondissecting aneurysms of the posterior circulation.

Methods

This prospective and descriptive study was conducted in 20 consecutive patients who harbored single aneurysms of the posterior circulation and who were treated using the SS approach in the last 3 years. The clinical and radiological assessment and follow-up of the patients were evaluated using the modified Rankin scale as well as with computed tomography angiography and digital subtraction angiography at discharge and at 1, 3, 6, and 12 months.

Results

Eleven of the 20 patients had subarachnoid hemorrhages, 3 presented with ischemia, 1 presented with brainstem compression, and the remaining 5 patients had incidentally discovered, asymptomatic lesions. Only 1 patient had a complication (occipital infarction) attributable to the SS procedure. One patient died of rebleeding 2 weeks after the procedure. At 1 month, 40% of the patients had a subtotal or total occlusion, which increased to 55% at 3 months and 85% at 6 months, with a final subtotal or total occlusion rate of 80% at 1 year. The SS procedure in 1 case was considered a failure at 6 months because no change had been noted since the 1-month follow-up. One case showed partial occlusion and 1 case showed recanalization.

Conclusions

Use of SS for aneurysms in the posterior circulation complex is a safe and effective technique, demonstrating an occlusion rate of 80% at the 1-year follow up.
Impact of ischemic heart disease and atrial fibrillation on survival after spontaneous intracerebral hemorrhage
Authors: Tetri Sami , Mäntymäki Liisa , Juvela Seppo , Saloheimo Pertti , Pyhtinen Juhani , Rusanen Harri , Hillbom Matti
Published: June 2008

Object

The well-known predictors for increased early deaths after spontaneous intracerebral hemorrhage (ICH) include the clinical and radiological severity of bleeding as well as being on a warfarin regimen at the onset of stroke. Ischemic heart disease and atrial fibrillation may also increase early deaths. In the present study the authors aimed to elucidate the role of the last 2 factors.

Methods

The authors assessed the 3-month mortality rate in patients with spontaneous ICH (453 individuals) who were admitted to the stroke unit of Oulu University Hospital within a period of 11 years (1993–2004).

Results

The 3-month mortality rate for the 453 patients was 28%. The corresponding mortality rates were 42% for the patients who had ischemic heart disease and 61% for those with atrial fibrillation on admission. The following independent predictors of death emerged after adjustment for sex and the use of warfarin or aspirin at the onset of ICH: 1) ischemic heart disease (hazard ratio [HR] 1.67, 95% confidence interval [CI] 1.12–2.48, p < 0.02); 2) atrial fibrillation on admission (HR 1.79, 95% CI 1.12–2.86, p < 0.02); 3) the Glasgow Coma Scale score on admission (HR 0.82 per unit, 95% CI 0.79–0.87, p < 0.01); 4) size of hematoma (HR 1.11 per 10 ml, 95% CI 1.07–1.16, p < 0.01); 5) intraventricular hemorrhage (HR 2.62, 95% CI 1.71–4.02, p < 0.01); 6) age (HR 1.04 per year, 95% CI 1.02–1.06, p < 0.01); and 7) infratentorial location of the hematoma (HR 1.93, 95% CI 1.26–2.97, p < 0.01).

Conclusions

Both ischemic heart disease and atrial fibrillation independently and significantly impaired the 3-month survival of patients with ICH.
The effect of lumboventricular lavage and simultaneous low-frequency head-motion therapy after severe subarachnoid hemorrhage: results of a single center prospective Phase II trial
Authors: Hänggi Daniel , Liersch Julia , Turowski Bernd , Yong Mei , Steiger Hans-Jakob
Published: June 2008

Object

The authors of recent publications have suggested that a combination of cisternal irrigation and head-shaking therapy might reduce cerebral vasospasm after subarachnoid hemorrhage (SAH) and therefore improve outcome. The authors undertook this prospective nonrandomized Phase II study to analyze the effect of enhanced washout by lumboventricular irrigation in combination with head motion (lateral rotational therapy) on the clot clearance (CC) rate, development of cerebral vasospasm, and clinical outcome.

Methods

Forty patients with aneurysmal SAHs of World Federation of Neurosurgical Societies Grades II–V (Glasgow Coma Scale Scores 13–3) and Fisher Grade 3 or 4 were included in this study. The study and control groups each consisted of 20 patients. The protocol in the study group, after the aneurysm was secured and a ventricular drain inserted, included the insertion of 2 lumbar catheters for intrathecal irrigation with Ringer solution and intrathecal pressure monitoring. Moderate head rotation in a kinetic system was also applied and was continued for 5 days. The CC rate was monitored on daily computed tomography (CT) scans. Vasospasms were identified clinically with a focus on delayed ischemic neurological deficits (DINDs), daily transcranial Doppler (TCD) ultrasonography studies, and analysis of infarction rate on CT and cerebral angiography. The data obtained in both groups were statistically evaluated.

Results

There were no procedure-related complications. The overall CC rate did not differ significantly between the groups, but there was a trend toward accelerated resolution in the study group. During observation, a new neurological deficit developed in 1 patient (5%) in the study group and 4 patients (20%) in the control group. Ischemic areas on CT scans related to vasospasm were demonstrated in 2 patients (10%) in the study group and 6 patients (30%) in the control group. The incidence of angiographic vasospasm was approximately the same in both groups. The pooled TCD flow velocities measured over a period of 14 days showed lower mean values in the study group than in the control group (p = 0.00002). The clinical outcome in the study group as evaluated with the modified Rankin scale was better in the study group than in the control group after 3 (p = 0.008) and 6 (p = 0.005) months.

Conclusions

The present study demonstrates that a combination of lumboventricular lavage and mechanical head motion reduces vasospasm on TCD ultrasonography, the incidence of DIND, and secondary infarctions on CT and improves clinical outcome. No obvious effect could be found on the rate of angiographic vasospasm.
Long-term surgical results with aneurysms involving the ophthalmic segment of the carotid artery
Authors: Raco Antonino , Frati Alessandro , Santoro Antonio , Vangelista Tommaso , Salvati Maurizio , Delfini Roberto , Cantore Giampaolo
Published: June 2008

Object

Because of the anatomical complexity of the paraclinoid region, the surgical treatment of aneurysms arising in the C6 segment of the internal carotid artery is extremely challenging. The authors' aim in this study was to describe the extended clinical follow-up and assess the short-term and long-term effectiveness of surgical treatment for these aneurysms, focusing on the clinical outcome and degree of aneurysm occlusion and recurrence.

Methods

The authors retrospectively analyzed the clinical records for patients treated surgically between 1973 and 2004 at the University of Rome, “La Sapienza.” Aneurysms were classified into the following 3 groups according to the site where they arose: the anteromedial, anterior or anterolateral, and posteromedial wall of the C6 segment.

Results

Of the 108 aneurysms in 104 patients treated, 63 (58%) were large or giant. Eighty-eight aneurysms in 84 patients were clipped, 16 underwent a high-flow bypass, 2 were trapped, 1 was wrapped, and 1 was left untreated. The mean follow-up was 126 months; 47 patients had a follow-up of > 10 years. Of the 88 aneurysms that were clipped, 6 (6.8%) had an incomplete occlusion that required an immediate reoperation in 1 case and at 2 years in another. Overall 6 patients (5.8%) had surgery-related permanent complications.

Conclusions

Mortality and morbidity rates depend mainly on the patient's preoperative Hunt and Hess grade subarachnoid hemorrhage, whereas surgical morbidity principally reflects excessive manipulation of the optic nerve or ischemic problems due to excessive temporary trapping undertaken without adequate neuroprotection. In expert hands, surgery (clipping and bypass procedures) is a definitive treatment for C6 aneurysms and has an acceptable complication rate.
Initial management of hydrocephalus associated with Chiari malformation Type I–syringomyelia complex via endoscopic third ventriculostomy: an outcome analysis
Authors: Hayhurst Caroline , Osman-Farah Jibril , Das Kumar , Mallucci Conor
Published: June 2008

Object

The aim of this study was to evaluate the efficacy of endoscopic third ventriculostomy (ETV) in patients with Chiari malformation Type I (CM-I) and hydrocephalus with or without syringomyelia.

Methods

The authors identified, in a prospective endoscopy database, 16 adults and children (age range 2–68 years) with CM-I and hydrocephalus that had been managed with ETV. They reviewed the clinical features and radiographic findings for all patients. Fifteen patients underwent ETV as a primary treatment, whereas 1 patient underwent the procedure at the time of shunt failure. All patients had symptomatic hydrocephalus with either aqueductal or fourth ventricular outflow obstruction. The mean duration of follow-up was 42 months.

Results

Fifteen patients (94%) remain shunt free following ETV for CM-I. Five (83%) of the 6 patients with a syrinx had improvement or resolution of the syrinx following ETV. Six patients (37.5%) underwent foramen magnum decompression for persistent CM-I– or syrinx-related symptoms. There was no cerebrospinal fluid leakage or intracranial pressure–related problem following foramen magnum decompression.

Conclusions

Endoscopic third ventriculostomy provides a durable method of treatment for hydrocephalus associated with CM-I. It is effective as a primary treatment, and the authors advocate its use as a replacement for routine ventriculoperitoneal shunt insertion in these patients. Management of the hydrocephalus alone is often sufficient and may obviate decompression, although a significant proportion of patients will still need both procedures.
Hand prehension recovery after brachial plexus avulsion injury by performing a full-length phrenic nerve transfer via endoscopic thoracic surgery
Authors: Xu Wen-Dong , Lu Jiu-Zhou , Qiu Yan-Qun , Jiang Su , Xu Lei , Xu Jian-Guang , Gu Yu-Dong
Published: June 2008

Object

The functional recovery of hand prehension after complete brachial plexus avulsion injury (BPAI) remains an unsolved problem. The authors conducted a prospective study to elucidate a new method of resolving this injury.

Methods

Three patients with BPAI underwent a new procedure during which the full-length phrenic nerve was transferred to the medial root of the median nerve via endoscopic thoracic surgery support. All 3 patients were followed up for a postoperative period of > 3 years.

Results

The power of the palmaris longus, flexor pollicis longus, and the flexor digitorum muscles of all 4 fingers reached Grade 3–4/5, and no symptoms of respiratory insufficiency occurred.

Conclusions

Neurotization of the phrenic nerve to the medial root of the median nerve via endoscopic thoracic surgery is a feasible means of early hand prehension recovery after complete BPAI.
A novel endovascular clip system for the treatment of intracranial aneurysms: technology, concept, and initial experimental results
Authors: Marotta Thomas R. , Gunnarsson Thorsteinn , Penn Ian , Ricci Donald R. , Mcdougall Ian , Marko Alexei , Bourne Gyasi , Costa Leodante Da
Published: June 2008

Object

The authors describe a novel device for the endovascular treatment of intracranial aneurysms, the endovascular clip system (eCLIPs). Descriptions of the device and its delivery system as well as the results of flow model tests and the treatment of experimental aneurysms are provided.

Methods

The eCLIPs comprises a flexible hybrid implantable device (an anchor and a covered leaf) and a balloon catheter delivery system, designed to be positioned and activated in the parent vessel in such a way that the covered portion will abut the aneurysm neck. The eCLIPs was subjected to testing in glass, elastomeric, and cadaveric flow models to determine its navigability, orientation, and activation compared with commercially available stents. In a second experiment, 8 carotid artery sidewall aneurysms in swine were treated using eCLIPs. The degree of occlusion was observed on angiography immediately following and 30 days after device activation, and a histological analysis was performed at 30 days.

Results

The device could navigate tortuous glass models and human cadaveric vessels. Compared with commercially available stents, the eCLIPs performed well. It could be navigated, oriented, and activated easily and reliably. With regard to the 8 porcine experimental aneurysms, immediate postactivation angiograms confirmed complete occlusion of 4 lesions and near occlusion of the other 4. Angiographic follow-up at 30 days postactivation showed occlusion of all 8 aneurysms and patency of all parent vessels. Histopathological analysis revealed aneurysm healing, with smooth-muscle cells growing across the lesion neck to allow reendothelialization.

Conclusions

Aneurysm occlusion with a single extrasaccular endovascular device has potential advantages. The authors believe that eCLIPs may prove to be a useful tool in the endovascular treatment of cerebral aneurysms. The system should reduce risks associated with coiling, procedure time, costs, and radiation exposure. The device satisfactorily occluded 8 experimental sidewall aneurysms. The observed healing pattern is similar to that seen after microsurgical clipping.
Communicating hydrocephalus after endovascular coiling of unruptured aneurysms
Authors: Mitha Alim P. , Wong John H. , Lu Jian-Qiang , Morrish William F. , Hudon Mark E. , Hu William Y.
Published: June 2008

✓ To the authors' knowledge, only 1 case of communicating hydrocephalus after endovascular coiling of unruptured brain aneurysms has been reported previously. Here, they report on 2 such cases of delayed communicating hydrocephalus after treatment with hydrogel-coated coils and offer the first histopathological evidence of foreign material, presumably related to the coils, as the cause of hydrocephalus.