bluuebunny/crossref_metadata_2025 huggingface dataset:
Second-by-Second Characterization of Cold-Start Gas-Phase and Air Toxic Emissions from a Light-Duty Vehicle
Authors: Sentoff Karen M. , Robinson Mitchell K. , Holmén Britt A.
Published: October 2010

Tailpipe pollutants from motor vehicles are linked to environmental concerns and human health issues. Gasoline engine ignition produces a significant portion of trip emissions, but few studies have quantified mobile source air toxic (MSAT) species for light-duty vehicles during cold start. Real-world tailpipe emissions were measured from a 1999 Toyota Sienna minivan with the University of Vermont total onboard tailpipe emissions measurement system. A Fourier transform infrared spectrometer measured 27 gas-phase emissions for cold start, extended idle, and warm-up driving at 1-s temporal resolution. Analysis demonstrated that (a) time to optimal function of emissions control devices was not indicated by one species, but varied for different pollutants; (b) extended idling after cold start produced elevated emissions for MSAT species as compared to warm-up driving; and (c) ambient temperatures ranging from 9.5°C to 38.4°C affected species from each emission category, with the exception of carbon dioxide. Carbon monoxide produced peak emissions three orders of magnitude higher than hot-stabilized conditions for an average of 90 s, regardless of operating conditions, while nitric oxide peak emissions were over an order of magnitude higher during warm-up driving than extended idle. Peak MSAT emissions, up to two orders of magnitude higher than hot-stabilized idle, were maintained or increased during extended idle and decreased to baseline within 100 to 200 s of warm-up driving. Results indicate extended idling after cold starts prolongs elevated concentrations of MSAT emissions, suggesting that recent policy efforts to reduce vehicle idling behavior could limit potential human exposure to the toxic exhaust constituents.
Ecology and Transportation
Authors: Giles Randy , Golbek Scott , Sullivan Amanda , Wood Jerry
Published: October 2010

The Washington State Department of Transportation's (WSDOT) I-90 Snoqualmie Pass East Project has presented WSDOT engineers with many unique design challenges when integrating the ecological needs of the area with the transportation objectives of the project. The project faces issues of capacity, deteriorating concrete pavement, unstable rock slopes, and road closures associated with avalanches; there is also a real need to improve ecological connectivity of the area. I-90 is a physical barrier to the north–south movement of fish and wildlife. Wildlife attempting to cross the Interstate present a safety concern to motorists, and the barrier that I-90 forms between upstream and downstream aquatic habitats affects fish passage and hydrologic processes. To identify areas where investments in ecological connectivity should be made, WSDOT worked with dozens of agencies that manage land resources in the project area to design bridges and culverts that improve wildlife and aquatic connections. Integrating ecological objectives presented many design engineering challenges because of the project area's unfavorable construction conditions. Trade-offs and compromises between WSDOT and land resource managers were needed to find suitable solutions to problems. Issues that required compromises included eliminating scour issues while maximizing restoration areas; improving ground conditions for foundations without impacts to wetlands, endangered species, and footprint; creating habitat connections while treating stormwater; and designing bridges for clearance and connecting habitat.
Acoustic Radiation from Pavement Joint Grooves between Concrete Slabs
Authors: Donavan Paul R.
Published: October 2010

Sound generation and radiation from grooves in the joints between concrete slabs were modeled using relationships previously established for tire groove resonances and groove air pumping. Resonant behavior was clearly established from both in-lab and on-road onboard sound pressure level data. The strength of the noise source was found to be proportional to 20 times the logarithm of the groove cross-sectional area. This relationship, along with the accounting of residual texture background noise, was found to replicate that measured in laboratory testing. The model was then calibrated with the laboratory results and extended in speed range with a theoretical calculation of the sound radiation from the end of the joint groove. The predicted level produced by an isolated joint of specified dimension was then used to model the average sound intensity level for a pavement with a user-specified distance between joints, vehicle speed, and pavement texture-generated noise level. For smaller groove cross-sectional areas (~0.25 in.2), the contribution of joint grooves was on the order of 1 dB for quieter pavement textures. For larger cross-sectional areas, such as a groove width of 1/2 in. and depth of 1 in., the contribution increased to almost 3 dB.
Magnetic resonance imaging grading of interspinous ligament degeneration of the lumbar spine and its relation to aging, spinal degeneration, and segmental motion
Authors: Keorochana Gun , Taghavi Cyrus E. , Tzeng Shiau-Tzu , Morishita Yuichiro , Yoo Jeong Hyun , Lee Kwang-Bok , Liao Jen-Chung , Wang Jeffrey C.
Published: October 2010

Object

Degenerative changes of the interspinous ligaments (ISLs) have generally been ignored in previous studies. Factor-related causes, the effects that these changes have on other structures within the spinal functional unit, and their relation to kinematic changes in the spine are lacking. In this study, the authors evaluated the reliability of a proposed MR imaging grading system of ISL degeneration (ISLD). They also investigated the relationship between ISLD and aging, disc/facet joint degeneration, and lumbar segmental motion.

Methods

The authors studied 256 lumbar motion segments from L-2 to S-1 in 64 patients (35 men and 29 women) with a mean age of 46.08 years (range 23–85 years). An MR imaging–based grading system for ISLD was developed and ranged from Grade A (mild) to Grade D (severe). The reliability was tested, and the correlation of the grade with the severity of the disc and facet joint degeneration was examined. The segmental motion of each functional unit was measured using flexion/extension MR imaging, and their relationships with ISL grades were identified.

Results

Grade A was observed in 115 levels (44.9%), Grade B in 105 (41.0%), Grade C in 15 (5.9%), and Grade D in 21 levels (8.2%). The kappa coefficients for intraobserver and interobserver agreements were substantial to excellent (intraobserver [0.871] and interobserver [0.721–0.807]). Grade D was observed primarily in elderly patients. Segmental motion tended to decrease in the most severe grade, with a significant difference in angular mobility. As the severity of ISLD increased, the severity of disc/facet joint degeneration increased (p < 0.001 and p < 0.05, respectively).

Conclusions

The authors proposed a reliable and reproducible grading system that may be used to investigate spinal kinematics in association with ISLD. The authors' findings illustrated the distribution of ISLD grades. The most severe grade occurred primarily in elderly patients. Mobility decreased in the most severe grade; therefore, the stage of ISLD should be taken into consideration when evaluating spinal stability.
Accuracy of percutaneous lumbar pedicle screw placement using the oblique or “owl's-eye” view and novel guidance technology
Authors: Idler Cary , Rolfe Kevin W. , Gorek Josef E.
Published: October 2010

Object

This study was conducted to assess the in vivo safety and accuracy of percutaneous lumbar pedicle screw placement using the owl's-eye view of the pedicle axis and a new guidance technology system that facilitates orientation of the C-arm into the appropriate fluoroscopic view and the pedicle cannulation tool in the corresponding trajectory.

Methods

A total of 326 percutaneous pedicle screws were placed from L-3 to S-1 in 85 consecutive adult patients. Placement was performed using simple coaxial imaging of the pedicle with the owl's-eye fluoroscopic view. NeuroVision, a new guidance system using accelerometer technology, helped align the C-arm trajectory into the owl's-eye view and the cannulation tool in the same trajectory. Postoperative fine-cut CT scans were acquired to assess screw position. Medical records were reviewed for complications.

Results

Five of 326 screws breached a pedicle cortex—all breaches were less than 2 mm—for an accuracy rate of 98.47%. Five screws violated an adjacent facet joint. All were at the S-1 superior facet and included in a fusion. No screw violated an adjacent mobile facet or disc space. There were no cases of new or worsening neurological symptoms or deficits for an overall clinical accuracy of 100%.

Conclusions

The owl's-eye technique of coaxial pedicle imaging with the C-arm fluoroscopy, facilitated by NeuroVision, is a safe and accurate means by which to place percutaneous pedicle screws for degenerative conditions of the lumbar spine. This is the largest series reported to use the oblique or owl's-eye projection for percutaneous pedicle screw insertion. The accuracy of percutaneous screw insertion with this technique meets or exceeds that of other reported clinical series or techniques.
Brachial plexus injury following spinal surgery
Authors: Uribe Juan S. , Kolla Jaya , Omar Hesham , Dakwar Elias , Abel Naomi , Mangar Devanand , Camporesi Enrico
Published: October 2010

Object

In the present study, the authors identified the etiology, precipitating factors, and outcomes of perioperative brachial plexus injuries following spine surgery.

Methods

We reviewed all the available literature regarding postoperative/perioperative brachial plexus injuries, with special concern for the patient's position during surgery, duration of surgery, the procedure performed, neurological outcome, and prognosis. We also reviewed the utility of intraoperative electrophysiological monitoring for prevention of these complications.

Results

Patient malpositioning during surgery is the main determining factor for the development of postoperative brachial plexus injury. Recovery occurs in the majority of cases but may require weeks to months of therapy after initial presentation.

Conclusion

Brachial plexus injuries are an increasingly recognized complication following spinal surgery. Proper attention to patient positioning with the use of intraoperative electrophysiological monitoring techniques could minimize injury.
Evaluation of pullout strength and failure mechanism of posterior instrumentation in normal and osteopenic thoracic vertebrae
Authors: Paxinos Odysseas , Tsitsopoulos Parmenion P. , Zindrick Michael R. , Voronov Leonard I. , Lorenz Mark A. , Havey Robert M. , Patwardhan Avinash G.
Published: October 2010

Object

There is limited data on the pullout strength of spinal fixation devices in the thoracic spine among individuals with different bone quality. An in vitro biomechanical study on the thoracic spine was performed to compare the pullout strength and the mechanism of failure of 4 posterior fixation thoracic constructs in relation to bone mineral density (BMD).

Methods

A total of 80 vertebrae from 11 fresh-frozen thoracic spines (T2–12) were used. Based on the results from peripheral quantitative CT, specimens were divided into 2 groups (normal and osteopenic) according to their BMD. They were then randomly assigned to 1 of 4 different instrumentation systems (sublaminar wires, pedicle screws, lamina claw hooks, or pedicle screws with wires). The construct was completed with 2 titanium rods and 2 transverse connectors, creating a stable frame. The pullout force to failure perpendicular to the rods as well as the pattern of fixation failure was recorded.

Results

Mean pullout force in the osteopenic Group A (36 vertebrae) was 473.2 ± 179.2 N and in the normal BMD Group B (44 vertebrae) was 1414.5 ± 554.8 N. In Group A, no significant difference in pullout strength was encountered among the different implants (p = 0.96). In Group B, the hook system failed because of dislocation with significantly less force than the other 3 constructs (931.9 ± 345.1 N vs an average of 1538.6 ± 532.7 N; p = 0.02). In the osteopenic group, larger screws demonstrated greater resistance to pullout (p = 0.011). The most common failure mechanism in both groups was through pedicle base fracture.

Conclusions

Bone quality is an important factor that influences stability of posterior thoracic implants. Fixation strength in the osteopenic group was one-fourth of the value measured in vertebrae with good bone quality, irrespective of the instrumentation used. However, in normal bone quality vertebrae, the lamina hook claw system dislocated with significantly less force when compared with other spinal implants. Further studies are needed to investigate the impact of different transpedicular screw designs on the pullout strength in normal and osteopenic thoracic spines.
Efficacy of the coadministration of granulocyte colony-stimulating factor and stem cell factor in the activation of intrinsic cells after spinal cord injury in mice
Authors: Osada Takahiro , Watanabe Masahiko , Hasuo Atsuhiro , Imai Masaaki , Suyama Kaori , Sakai Daisuke , Kawada Hiroshi , Matsumae Mitsunori , Mochida Joji
Published: October 2010

Object

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic cytokine that induces undifferentiated stem cells from the bone marrow (BM) into the peripheral blood. Stem cell factor (SCF) is also a hematopoietic cytokine that stimulates the differentiation and proliferation of neural stem cells and has neuroprotective effects. In cerebrally infarcted mice, the combination of G-CSF and SCF promotes the differentiation of BM-derived cells into neural cells, stimulates the proliferation of intrinsic neural stem cells, and improves motor function. The object of this study was to investigate the effects of these cytokines on BM stem cells, intrinsic cells, and motor function recovery in spinal cord–injured mice.

Methods

For marking BM-derived cells, the authors induced contusive spinal cord injury in mice transplanted with BM cells from green fluorescent protein (GFP)–transgenic mice after whole-body irradiation. These mice were treated with G-CSF and SCF in the subacute injury phase. Bromodeoxyuridine (BrdU) was injected into these mice to label proliferating cells. The cell numbers and phenotype of the BM-derived cells were evaluated, and the change in intrinsic cells (proliferation, accumulation, and differentiation) was noted using immunohistological analysis at 4 weeks postinjury (wpi). A behavior analysis was conducted until 12 wpi using the Basso, Beattie, Bresnahan locomotor rating scale.

Results

In the SCF + G-CSF group, improvement in hindlimb motor function was significantly greater than in the SCF group, G-CSF group, and sham-treatment (vehicle) group after 8 wpi. At 4 wpi, the number of GFP+ BM-derived cells induced in the lesion did not significantly differ between groups. At 4 wpi, the authors evaluated perilesional GFP− intrinsic spinal cord cells. The number of GFP− and F4/80+ cells was significantly greater in the SCF + G-CSF group than in the other 3 groups. As compared with the sham group, the number of NG2+/BrdU+ cells was significantly increased in the SCF + G-CSF group.

Conclusions

In this study, the combined administration of SCF and G-CSF in traumatic spinal cord injury not only improved motor function, but also induced the accumulation of intrinsic microglia and the active proliferation of intrinsic oligodendrocyte precursor cells.
Outcome after microsurgery in 14 patients with spinal cavernomas and review of the literature
Authors: Kivelev Juri , Niemelä Mika , Hernesniemi Juha
Published: October 2010

Object

Spinal cavernomas are rare, but can cause significant neurological deficits due to mass effect and extralesional hemorrhage. The authors present their results of microsurgical treatment of 14 consecutive patients with spinal cavernoma, and review the literature.

Methods

Of the 376 patients with cavernomas of the CNS treated at Helsinki University Central Hospital (a catchment area close to 2 million inhabitants) between January 1980 and June 2009, 14 (4%) had a spinal cavernoma. The authors reexamined and analyzed the patient files and images retrospectively. Median patient age at presentation was 45 years (range 20–57 years). The female/male ratio was equal. Median duration of symptoms before admission to the department was 12 months (range 0.1–168 months). Patients suffered from sensorimotor paresis, radicular pain, or neurogenic micturition disorders in different combinations or separately. Hemorrhage had occurred in 7 patients (50%) before surgery. In 9 patients (64%) the cavernoma was intramedullary, in 4 (29%) extradural, and in 1 intradural extramedullary. On MR imaging, 6 patients (43%) had a cavernoma in the cervical region, 7 (50%) in the thoracic region, and 1 (7%) in the lumbar region.

Results

Postoperatively, patients were followed up for a median of 3 years (range 1–10 years). At follow-up, 13 patients (93%) experienced significant improvement in motor ability after surgery, and all patients were able to walk with or without aid. Ten of the 11 patients with pain syndrome (91%) showed significant pain relief without recurrence. Micturition disorder was noted in 6 patients (43%) at follow-up, but in 5 the condition had existed before surgery. No patient improved in bladder function after surgery, and 1 patient developed micturition dysfunction postoperatively.

Conclusions

Microsurgical removal of spinal cavernomas alleviates sensorimotor deficits and pain caused by mass effect and hemorrhage. However, bladder dysfunction remains unchanged after surgery.
The role of stereotactic radiosurgery in the multimodal management of growth hormone–secreting pituitary adenomas
Authors: Stapleton Christopher J. , Liu Charles Y. , Weiss Martin H.
Published: October 2010

Growth hormone (GH)–secreting pituitary adenomas represent a common source of GH excess in patients with acromegaly. Whereas surgical extirpation of the culprit lesion is considered first-line treatment, as many as 19% of patients develop recurrent symptoms due to regrowth of previously resected adenomatous tissue or to continued growth of the surgically inaccessible tumor. Although medical therapies that suppress GH production can be effective in the management of primary and recurrent acromegaly, these therapies are not curative, and lifelong treatment is required for hormonal control. Stereotactic radiosurgery has emerged as an effective adjunctive treatment modality, and is an appealing alternative to conventional fractionated radiation therapy. The authors reviewed the growing body of literature concerning the role of radiosurgical procedures in the treatment armamentarium of acromegaly, and identified more than 1350 patients across 45 case series. In this review, the authors report that radiosurgery offers true hormonal normalization in 17% to 82% of patients and tumor growth control in 37% to 100% of cases across all series, while minimizing adverse complications. As a result, stereotactic radiosurgery represents a safe and effective treatment option in the multimodal management of primary or recurrent acromegaly secondary to GH-secreting pituitary adenomas.
Early descriptions of acromegaly and gigantism and their historical evolution as clinical entities
Authors: Mammis Antonios , Eloy Jean Anderson , Liu James K.
Published: October 2010

Giants have been a subject of fascination throughout history. Whereas descriptions of giants have existed in the lay literature for millennia, the first attempt at a medical description was published by Johannes Wier in 1567. However, it was Pierre Marie, in 1886, who established the term “acromegaly” for the first time and established a distinct clinical diagnosis with clear clinical descriptions in 2 patients with the characteristic presentation. Multiple autopsy findings revealed a consistent correlation between acromegaly and pituitary enlargement. In 1909, Harvey Cushing postulated a “hormone of growth” as the underlying pathophysiological trigger involved in pituitary hypersecretion in patients with acromegaly. This theory was supported by his observations of clinical remission in patients with acromegaly in whom he had performed hypophysectomy. In this paper, the authors present some of the early accounts of acromegaly and gigantism, and describe its historical evolution as a medical and surgical entity.
A systematic analysis of disease control in acromegaly treated with radiosurgery
Authors: Yang Isaac , Kim Won , De Salles Antonio , Bergsneider Marvin
Published: October 2010

Object

Stereotactic radiosurgery (SRS) has emerged as an adjuvant radiation-based therapy for pituitary adenomas. Here, the authors present a systematic analysis of SRS for growth hormone–secreting adenomas to characterize the efficacy of SRS in the treatment of acromegaly.

Methods

A comprehensive search of the English language literature revealed 970 patients with new, recurrent, or persistent acromegaly that had been treated using SRS along with assessable and quantifiable outcome data. Articles published between June 1998 and September 2009 were included in the analysis. Patient outcome data were aggregated and investigated based on tumor size, radiosurgery dose, and clinical outcomes both with and without medication.

Results

The overall disease control rate without medication was 48%–53%, and the overall disease control rate with or without medication was 73%. The overall mean duration of the reported follow-up was 48.5 ± 25.8 months. The mean overall tumor volume in this analysis was 2.11 ± 1.16 cm3. The Pearson product-moment correlation coefficient for tumor volume and cure rate was not significant (r = 0.0668, p = 0.8546).

Conclusions

Data from this analysis suggest that tumor size may not be a significant prognostic factor in disease control after radiosurgery for acromegaly. The overall disease control rate was approximately 48% without suppressive medications after radiosurgery for acromegaly. With the advancement of increasingly sophisticated stereotactic planning and tumor targeting, the precision of radiosurgery may continue to improve in the treatment of acromegaly.
Outcomes of ventriculoperitoneal shunt insertion in Sub-Saharan Africa
Authors: Gathura Esther , Poenaru Dan , Bransford Richard , Albright A. Leland
Published: October 2010

Object

Ventriculoperitoneal (VP) shunts in Sub-Saharan Africa are traditionally associated with high complication rates and poor outcomes. The aim of this study was to review one large institutional experience with VP shunts, to evaluate the feasibility of shunt insertion procedures with acceptable long-term outcomes in Africa, and to identify factors correlated with good and/or poor outcomes.

Methods

A retrospective study was conducted by reviewing the charts of all children who underwent primary (93%) or subsequent VP shunt insertions at the Kijabe Hospital between November 2004 and March 2007. Epidemiological data, clinical investigations, etiology of the hydrocephalus, details of the VP shunt insertion, outcome at follow-up, and morbidity and mortality data were collected. Outcomes were graded as good, fair, or poor, according to visual, motor, and seizure criteria.

Results

The authors analyzed 593 VP shunt insertions in 574 patients. The sex distribution was 53% male and 47% female. The mean age at shunt insertion was 8.5 months (range 0–309 months). The commonest etiologies for hydrocephalus were spina bifida (43.4%) and postinfectious (27.7%). Follow-up was available in 76% of children, with a mean follow-up period of 8.9 months (range 2–30.5 months). The median patient age was 3.3 months. The overall shunt function rate at 2 years was 65%, and the complication rate per procedure was 20%, with infection encountered in 9.1% and shunt malfunction in 11%. Complications were significantly related to hydrocephalus etiology and to sex (p = 0.03 and p = 0.01, respectively). Overall outcomes were good in 40.2% and poor in 59.8%. Overall mortality in the group was 7.1%. Younger patients who survived had an overall good outcome (p = 0.0001). Only 10% of patients with a head circumference greater than 60 cm had a good outcome.

Conclusions

Despite limited resources, VP shunt procedures can be carried out in Sub-Saharan Africa with acceptable complication rates and fair long-term outcomes.
Spinal dural closure with nonpenetrating titanium clips in pediatric neurosurgery
Authors: Kaufman Bruce A. , Matthews Anne E. , Zwienenberg-Lee Marike , Lew Sean M.
Published: October 2010

Object

The authors report a retrospective review of their experience using nonpenetrating titanium anastomotic clips for dural closure in 27 pediatric cases (26 patients) of spinal surgery for a variety of diagnoses. The goal of this review was to define the utility of these clips in pediatric neurosurgical spinal procedures, identify complications of their use, and assess the effects on postoperative imaging because of their use.

Methods

Institutional review board approval was obtained for a retrospective chart review of all patients in whom titanium dural clips had been utilized. Patients were identified over a 2-year period using hospital and clinic records, and data were collected on the patient demographics, surgical diagnosis and procedure, durotomy location and length, and adjunctive closure methods. Postoperative complications were assessed. When available, postoperative imaging data were reviewed.

Results

Twenty-six patients underwent 27 operations over a 20-month period. They ranged in age from 2.5 months to 18.5 years, with a median age of 3.2 years and an average age of 5.8 years. The operative diagnosis was some form of spinal dysraphism in 19 patients, with a syrinx or dural tear in 2 patients each, and an arachnoid cyst in 3 cases; 1 patient had a tumor resected. Operative levels included lumbosacral (19), thoracic (7), and cervical (1). Dural exposure was limited to 1 laminar level in 16 cases, 2 levels in 8, and 3 levels in 1; 2 cases involved focal dural tears. A combination of additional hemostatic and tissue sealant materials was applied over the clips in 16 cases. One patient required reoperation 13 months after clip placement. Prior clip use did not make subsequent exposure and opening more complicated. No significant complications were identified in the follow-up period ranging from 1 to 24 months. There were no documented CSF leaks. The clips are not easily seen on plain radiographs and did not cause artifacts or distortion on either CT or MR imaging.

Conclusions

Nonpenetrating titanium anastomotic clips afford an effective means of closure while limiting the exposure needed, and thus allowing more minimally invasive approaches. In tight spaces, dural closure is accomplished more easily and faster with the clips as compared with conventional suturing. No significant complications were seen from clip use, and the clips did not interfere with postoperative imaging.
Rapamycin as an alternative to surgical treatment of subependymal giant cell astrocytomas in a patient with tuberous sclerosis complex
Authors: Birca Ala , Mercier Claude , Major Philippe
Published: October 2010

Tuberous sclerosis complex (TSC) is associated with the potential development of benign hamartomas, including subependymal giant cell astrocytomas (SEGAs). Intracranial hypertension can be caused by SEGAs due to their propensity to block the foramen of Monro. The traditional management approach is to monitor SEGAs with periodic neuroimaging and to resect those that exhibit serial growth and/or cause clinical signs of intracranial hypertension. Recent observations suggest that rapamycin therapy may induce partial regression of SEGAs, therefore providing a potential alternative to resection. The authors present the case of an 8-year-old girl with bilateral SEGAs that led to progressive hydrocephaly and incipient signs of papilledema. Three months after initiating rapamycin therapy, the SEGAs exhibited significant reduction in size (82.6% on the left and 46.7% on the right), and the lesions remained stable 5 months later. Compared with previous case reports, similar or even greater antitumor efficacy was achieved with much lower trough levels of rapamycin (10–15 compared with 3.3–4.5 ng/ml, respectively). The authors discuss various aspects of rapamycin therapy and address unresolved issues that highlight the need for further prospective clinical trials.
Transsphenoidal surgery in patients with acromegaly: operative strategies for overcoming technically challenging anatomical variations
Authors: Zada Gabriel , Cavallo Luigi M. , Esposito Felice , Fernandez-Jimenez Julio Cesar , Tasiou Anastasia , De Angelis Michelangelo , Cafiero Tullio , Cappabianca Paolo , Laws Edward R.
Published: October 2010

Object

In addition to difficulties with anesthetic and medical management, transsphenoidal operations in patients with longstanding acromegaly are associated with inherent intraoperative challenges because of anatomical variations that occur frequently in these patients. The object of this study was to review the overall safety profile and anatomical/technical challenges associated with transsphenoidal surgery in patients with acromegaly.

Methods

The authors performed a retrospective analysis of 169 patients who underwent endoscopic transsphenoidal operations for growth hormone–secreting adenomas to assess the incidence of surgical complications. A review of frequently occurring anatomical challenges and operative strategies employed during each phase of the operation to address these particular issues was performed.

Results

Of 169 cases reviewed, there was no perioperative mortality. Internal carotid artery injury occurred in 1 patient (0.6%) with complex sinus anatomy, who remained neurologically intact following endovascular unilateral carotid artery occlusion. Other complications included: significant postoperative epistaxis (5 patients [3%]), transient diabetes insipidus (5 patients [3%]), delayed symptomatic hyponatremia (4 patients [2%]), CSF leak (2 patients [1%]), and pancreatitis (1 patient [0.6%]). Preoperative considerations in patients with acromegaly should include a cardiopulmonary evaluation and planning regarding intubation and other aspects of the anesthetic technique. During the nasal phase of the transsphenoidal operation, primary challenges include maintaining adequate visualization and hemostasis, which is frequently compromised by redundant, edematous nasal mucosa and bony hypertrophy of the septum and the nasal turbinates. During the sphenoid phase, adequate bony removal, optimization of working space, and correlation of imaging studies to intraoperative anatomy are major priorities. The sellar phase is frequently challenged by increased sellar floor thickness, distinct patterns of tumor extension and bony invasion, and anatomical variations in the caliber and course of the internal carotid artery. Specific operative techniques for addressing each of these intraoperative challenges are discussed.

Conclusions

Transsphenoidal surgery in patients with longstanding acromegaly frequently poses greater challenges than operations for other types of sellar lesions, yet these challenges may be safely and effectively overcome with the anticipation of specific issues and implementation of various intraoperative techniques.
Stereotactic radiosurgery as primary and salvage treatment for brain metastases from breast cancer
Authors: Kondziolka Douglas , Kano Hideyuki , Harrison Gillian L. , Yang Huai-che , Liew Donald N. , Niranjan Ajay , Brufsky Adam M. , Flickinger John C. , Lunsford L. Dade
Published: October 2010

Object

To evaluate the role of stereotactic radiosurgery (SRS) in the management of brain metastases from breast cancer, the authors assessed clinical outcomes and prognostic factors for survival.

Methods

The records from 350 consecutive female patients who underwent SRS for 1535 brain metastases from breast cancer were reviewed. The median patient age was 54 years (range 19–84 years), and the median number of tumors per patient was 2 (range 1–18 lesions). One hundred seventeen patients (33%) had a single metastasis to the brain, and 233 patients (67%) had multiple brain metastases. The median tumor volume was 0.7 cm3 (range 0.01–48.9 cm3), and the median total tumor volume for each patient was 4.9 cm3 (range 0.09–74.1 cm3).

Results

Overall survival after SRS was 69%, 49%, and 26% at 6, 12, and 24 months, respectively, with a median survival of 11.2 months. Factors associated with a longer survival included controlled extracranial disease, a lower recursive partitioning analysis (RPA) class, a higher Karnofsky Performance Scale score, a smaller number of brain metastases, a smaller total tumor volume per patient, the presence of deep cerebral or brainstem metastases, and HER2/neu overexpression. Sustained local tumor control was achieved in 90% of the patients. Factors associated with longer progression-free survival included a better RPA class, fewer brain metastases, a smaller total tumor volume per patient, and a higher tumor margin dose. Symptomatic adverse radiation effects occurred in 6% of patients. Overall, the condition of 82% of patients improved or remained neurologically stable.

Conclusions

Stereotactic radiosurgery was safe and effective in patients with brain metastases from breast cancer and should be considered for initial treatment.
Surgical outcomes for older patients with glioblastoma multiforme: preoperative factors associated with decreased survival
Authors: Chaichana Kaisorn L. , Chaichana Khan K. , Olivi Alessandro , Weingart Jon D. , Bennett Richard , Brem Henry , Quiñones-Hinojosa Alfredo
Published: October 2010

Object

As the population ages, the incidence of glioblastoma multiforme (GBM) among older patients (age > 65 years) will increase. Older patients, unlike their younger counterparts, are not often offered aggressive surgery because of their age, comorbidities, and potential inability to tolerate surgery. The goal of this study was to identify preoperative factors associated with decreased survival for older patients who underwent resection of a GBM. The identification of these factors may provide insight into which patients would benefit most from aggressive surgery.

Methods

All patients older than 65 years who underwent nonbiopsy resection of an intracranial GBM at a single institution between 1997 and 2007 were retrospectively reviewed. Factors associated with overall survival were assessed using multivariate proportional hazards regression analysis after controlling for peri- and postoperative factors known to be associated with outcome (extent of resection, carmustine wafer implantation, temozolomide chemotherapy, and radiation therapy). Variables with p < 0.05 were considered statistically significant.

Results

A total of 129 patients with an average age of 73 ± 5 years met the inclusion/exclusion criteria. At last follow-up, all 129 patients had died, with a median survival of 7.9 months. The preoperative factors that were independently associated with decreased survival were Karnofsky Performance Scale (KPS) score less than 80 (p = 0.001), chronic obstructive pulmonary disease (p = 0.01), motor deficit (p = 0.01), language deficit (p = 0.005), cognitive deficit (p = 0.02), and tumor size larger than 4 cm (p = 0.002). Patients with 0–1 (Group 1), 2–3 (Group 2), and 4–6 (Group 3) of these factors had statistically different survival times, where the median survival was 9.2, 5.5, and 4.4 months, respectively. In log-rank analysis, the median survival for Group 1 was significantly longer than that for Group 2 (p = 0.004) and Group 3 (p < 0.0001), while Group 2 had longer survival than Group 3 (p = 0.02).

Conclusions

Older patients with an increasing number of these factors may not benefit as much from aggressive surgery as patients with fewer factors. This may provide insight into identifying which patients older than 65 years of age may benefit from aggressive surgery.
Meningoencephalocele: a late complication of Le Fort III midfacial advancement in a patient with Crouzon syndrome
Authors: Ridgway Emily B. , Ropper Alexander E. , Mulliken John B. , Padwa Bonnie L. , Goumnerova Liliana C.
Published: October 2010

Complications of Le Fort III midfacial advancement include CSF rhinorrhea, meningitis, and ocular and cerebral injury. This report reviews the anatomy of the Le Fort III osteotomies and their relevance to the unusual complication of meningoencephalocele.

In this report, a young male patient with Crouzon syndrome underwent subcranial midfacial advancement at the age of 10 years for obstructive sleep apnea and ocular exposure. He presented 4 years later complaining of nasal obstruction. On physical examination, a mucous-covered mass was noted in the left upper nasal vault medial to the turbinates. Computed tomography scanning and MR imaging confirmed the diagnosis of frontoethmoidal meningoencephalocele. Repair of the meningoencephalocele was accomplished using a combined neurosurgery and plastic surgery approach.

Meningoencephalocele is a rare complication of subcranial midfacial advancement. The abnormal anatomy of the anterior cranial base in patients with syndromic craniosynostosis places them at greater risk for fracture of the cribriform plate and dural tears during this procedure. Unrecognized dural injury is the etiology of this complication in this young patient; however, elevated intracranial pressure may have been a confounding factor. Attention to the anatomy of the anterior cranial base, as seen on sagittal CT images, will aid in preventing this complication.
Impact of 5,10-methylenetetrahydrofolate reductase gene polymorphism on neural tube defects
Authors: Harisha Poomagame Narasimhamurthy , Devi B. Indira , Christopher Rita , Kruthika-Vinod Tumkur Puttasiddhappa
Published: October 2010

Object

Neural tube defects (NTDs) are among the most common congenital malformations worldwide. Their etiology and exact mechanisms of development are incompletely understood. Many enzymes involved in folate metabolism and the genes encoding these enzymes have been studied as candidates in their etiology. A mutation in the methylenetetrahydrofolate reductase (MTHFR) gene—a C→T transition at nucleotide 677—is one among them. The mutation results in substitution of alanine by valine at a functionally important site in the enzyme. It has been shown to be a risk factor for development of NTDs in certain populations. The present study was conducted to evaluate the role of MTHFR 677 C→T mutation as a risk factor for NTD in the South Indian population and to determine the relative importance of the genotypes in the affected child and its mother.

Methods

Blood samples were collected from the test and the control groups. The test group consisted of children with NTDs and their mothers, while the control group consisted of apparently healthy controls. MTHFR C677T polymorphism in the 3 groups was determined by polymerase chain reaction and restriction fragment length polymorphism studies. Comparison of polymorphism in the 3 groups was using the chi-square test.

Results

There was a significant difference in the prevalence of MTHFR 677 C→T mutation among the 3 groups (p = 0.002). The risk conferred by the TT genotype in the child was statistically significant (OR 12.625, 95% CI 1.430–111.465). In the mothers, however, although there was an increased prevalence of the mutation compared with the control individuals, the difference was not statistically significant (p = 0.152).

Conclusions

The MTHFR 677TT genotype is considered to be a definite risk factor for development of NTDs. It is the TT genotype status of the developing embryo, rather than the TT genotype status of its mother, that is the critical genetic determinant of MTHFR-related NTD risk.
La Cour Rehnquist et le fédéralisme aux Etats-Unis : peut-on parler d’un projet néofédéral ?
Authors: Vergniolle de Chantal François
Published: October 2010

L’article se propose de faire un bilan critique de la jurisprudence de la Cour Suprême américaine favorable aux États fédérés. Depuis 1991, la Cour renoue avec une attitude décentralisatrice qui, juridiquement, avait disparue depuis les années trente. Cet ensemble de décision est le résultat d’un projet de la majorité conservatrice de la Cour. Mais ce projet, qui renvoie à une tradition politique ancienne aux États-Unis, celle de «l’antifédéralisme», est encore loin d’être abouti. Les incohérences philosophiques, politiques et historiques, dont l’article rend compte, sont encore trop importantes pour que l’on puisse parler de théorisation alternative du fédéralisme. Le cas Bush v. Gore qui a décidé de l’élection présidentielle de 2000 illustre parfaitement les fragilités de la jurisprudence antifédérale de la Cour. Non seulement les pressions politiques peuvent conduire la Cour à abandonner l’engagement néofédéral, mais le fédéralisme lui-même, c’est là notre conclusion, est fondamentalement une pratique et pas une théorie. Il est, de ce fait, impossible d’en définir un équilibre idéal.
Genetic Diversity, Population Structure, and Linkage Disequilibrium in U.S. Elite Winter Wheat
Authors: Zhang Dadong , Bai Guihua , Zhu Chengsong , Yu Jianming , Carver Brett F.
Published: October 2010

Information on genetic diversity and population structure of elite wheat (Triticum aestivum L.) breeding lines promotes effective use of genetic resources. We analyzed 205 elite wheat breeding lines from major winter wheat breeding programs in the USA using 245 markers across the wheat genomes. This collection showed a high level of genetic diversity as reflected by allele number per locus (7.2) and polymorphism information content (0.54). However, the diversity of U.S. modern wheat appeared to be lower than previously reported diversity levels in worldwide germplasm collections. As expected, this collection was highly structured according to geographic origin and market class with soft and hard wheat clearly separated from each other. Hard wheat accessions were further divided into three subpopulations. Linkage disequilibrium (LD) was primarily distributed around centromere regions. The mean genome‐wide LD decay estimate was 10 cM (r2 > 0.1), although the extent of LD was highly variable throughout the genome. Our results on genetic diversity of different gene pools and the distribution of LD facilitates the effective use of genetic resources for wheat breeding and the choice of marker density in gene mapping and marker‐assisted breeding.
Increased Risk of Autoimmune Disease in Families with Wegener’s Granulomatosis
Authors: KNIGHT ANN , SANDIN SVEN , ASKLING JOHAN
Published: October 2010

Objective.

The etiology of Wegener’s granulomatosis (WG) is unknown. Susceptibility genes for WG that also affect the risks of other autoimmune/inflammatory diseases have been identified, indicating the existence of shared interdisease genetic susceptibilities. To determine the effect, on a population level, of shared susceptibility on disease risk, we assessed the occurrence of autoimmune/inflammatory disease in first-degree relatives of patients with WG.

Methods.

In the Swedish Hospital Discharge Register we identified 2288 individuals discharged with the diagnosis of WG between 1970 and 2003. Through linkage to the Swedish Multi-generation Register we identified 787 parents, 1212 siblings, and 3650 children of these patients. From the Register of Total Population we identified 10 controls for each patient with WG, and 65,000 of their first-degree relatives. Through linkage to the nationwide Outpatients Register, we identified autoimmune/inflammatory disease among all relatives. Relative risks were estimated as hazard ratio (HR) using Cox regression. The study period was 2001–2006.

Results.

Biological first-degree relatives of patients with WG were at a moderately increased risk of any autoimmune/inflammatory disease (HR 1.32, 95% CI 1.18–1.49), including specific associations with, for example, multiple sclerosis (HR 1.92, 95% CI 1.16–3.16), Sjögren’s syndrome (HR 2.00, 95% CI 1.07–3.73), and seropositive rheumatoid arthritis (HR 1.54, 95% CI 1.09–2.19).

Conclusion.

Relatives of patients with WG are at increased risk of being diagnosed with other autoimmune/inflammatory diseases, indicating shared susceptibility between WG and other auto-immune/inflammatory disease.
Disease Activity, Physical Function, and Radiographic Progression After Longterm Therapy with Adalimumab Plus Methotrexate: 5-Year Results of PREMIER
Authors: van der HEIJDE DÉSIRÉE , BREEDVELD FERDINAND C. , KAVANAUGH ARTHUR , KEYSTONE EDWARD C. , LANDEWÉ ROBERT , PATRA KAUSHIK , PANGAN AILEEN L.
Published: October 2010

Objective.

To evaluate the efficacy and safety of initial combination treatment with adalimumab (ADA) and methotrexate (MTX) versus monotherapy with ADA or MTX during an open-label extension of PREMIER.

Methods.

Patients with early rheumatoid arthritis (RA) received blinded ADA plus MTX, ADA alone, or MTX alone for 2 years in PREMIER. At Year 2, patients could enroll in an open-label extension and receive ADA monotherapy; MTX could be added at the investigator’s discretion. Longterm efficacy results are presented as observed data.

Results.

In the open-label period, 497 of the original 799 randomized patients had ≥ 1 dose of ADA (by original randomization: ADA plus MTX, n = 183; ADA, n = 159; MTX, n = 155). In the completers cohort [patients with available Year-5 ACR responses and modified total Sharp scores (mTSS)], the Year-5 mean change from baseline in mTSS for the ADA+MTX arm (n = 124) was 2.9, compared with 8.7 and 9.7 in the ADA (n = 115) and MTX (n = 115) arms. Comprehensive disease remission, defined as the combination of DAS28 remission, normal function (Health Assessment Questionnaire ≤ 0.5), and radiographic nonprogression (ΔmTSS ≤ 0.5), was achieved by more patients in the initial ADA+MTX arm (35%) than in the ADA (13%) or MTX (14%) arms.

Conclusion.

Initial combination treatment with ADA plus MTX, followed by open-label ADA, led to better longterm clinical, functional, and radiographic outcomes than either initial ADA or MTX monotherapy during 5 years of treatment.
Summer and Winter Spatial Habitat Use by the Lake Erie Watersnake
Authors: Stanford Kristin M. , King Richard B. , Wynn Doug
Published: October 2010

In an effort to provide information to guide habitat management for the Lake Erie watersnake Nerodia sipedon insularum, a federally threatened and Ohio state endangered species, we used radiotelemetry to obtain spatial habitat data for adult snakes during the summer active season and during winter hibernation. During the summer active season, terrestrial habitat use was limited to a narrow band of shoreline. Among individuals, maximum distance inland from shore ranged from 1 to 50 m (mean  =  8 m) and linear extent of shoreline ranged from 30 to 1,360 m (mean  =  261 m). Winter hibernation occurred at varying distances inland with individual hibernation sites ranging from 1 to 580 m (mean  =  29 m) from shore. Habitat use did not differ between males and females. Existing U.S. Fish and Wildlife Service habitat management guidelines suggest that ground-disturbing activities within potential hibernation areas (defined as terrestrial habitat within 161 m of shore) should be avoided in winter to prevent harm to hibernating snakes. They suggest further that excavation and removal of shrubs, standing or downed trees, root masses, animal burrows, piled rocks, cliffs, or bedrock within 21 m of shore should be avoided in summer to prevent harm to active snakes. Given that Lake Erie watersnakes have recovered to the point where delisting is being proposed, these habitat guidelines appear to be sufficient. However, maintaining voluntary compliance with habitat guidelines and meeting the need for continued public outreach will be vital to ensure long-term persistence.
Prasugrel as Antiplatelet Therapy in Patients With Acute Coronary Syndromes or Undergoing Percutaneous Coronary Intervention
Authors: Fletcher Barbara , Thalinger Karen K.
Published: October 2010

The authors provide information on prasugrel, compare and contrast it with clopidogrel, and review the use of prasugrel in patients who require an antiplatelet agent.