bluuebunny/crossref_metadata_2025 huggingface dataset:
Genomics of medulloblastoma: from Giemsa-banding to next-generation sequencing in 20 years
Authors: Northcott Paul A. , Rutka James T. , Taylor Michael D.
Published: December 2009

Advances in the field of genomics have recently enabled the unprecedented characterization of the cancer genome, providing novel insight into the molecular mechanisms underlying malignancies in humans. The application of high-resolution microarray platforms to the study of medulloblastoma has revealed new oncogenes and tumor suppressors and has implicated changes in DNA copy number, gene expression, and methylation state in its etiology. Additionally, the integration of medulloblastoma genomics with patient clinical data has confirmed molecular markers of prognostic significance and highlighted the potential utility of molecular disease stratification. The advent of next-generation sequencing technologies promises to greatly transform our understanding of medulloblastoma pathogenesis in the next few years, permitting comprehensive analyses of all aspects of the genome and increasing the likelihood that genomic medicine will become part of the routine diagnosis and treatment of medulloblastoma.
Using ex vivo proton magnetic resonance spectroscopy to reveal associations between biochemical and biological features of meningiomas
Authors: Pfisterer Wolfgang K. , Nieman Ronald A. , Scheck Adrienne C. , Coons Stephen W. , Spetzler Robert F. , Preul Mark C.
Published: December 2009

Object

The goal in this study was to determine if proton (1H) MR spectroscopy can differentiate meningioma grade and is associated with interpretations of biological behavior; the study was performed using ex vivo high-resolution spectra indicating metabolic characteristics.

Methods

Sixty-eight resected tissue samples of meningiomas were examined using ex vivo 1H MR spectroscopy. Of these meningiomas, 46 were WHO Grade I, 14 were WHO Grade II, and 8 were WHO Grade III. Fifty-nine were primary meningiomas and 9 were recurrences. Invasion of adjacent tissue (dura mater, bone, venous sinus, brain) was found in 32 cases. Thirty-nine meningiomas did not rapidly recur (as defined by expansion on MR imaging within a 5-year follow-up period), whereas rapid recurrence was confirmed in 24 meningiomas, and follow-up status was unknown in 5 cases.

Results

The absolute concentrations of total alanine and creatine were decreased in high-grade compared with low-grade meningiomas, as was the ratio of glycine to alanine (all p < 0.05). Additionally, alanine and the glycine/alanine ratio distinguished between primary and recurrent meningiomas (all p < 0.05). Finally, the absolute concentrations of alanine and creatine, and the glycine/alanine and choline/glutamate ratios were associated with rapid recurrence (p < 0.05).

Conclusions

. These data indicate that meningioma tissue can be characterized by metabolic parameters that are not typically identified by histopathological analysis alone. Creatine, glycine, and alanine may be used as markers of meningioma grade, recurrence, and the likelihood of rapid recurrence. These data validate a previous study of a separate group of Grade I meningiomas.
Neurofibromatosis Type 1 and tumorigenesis: molecular mechanisms and therapeutic implications
Authors: Gottfried Oren N. , Viskochil David H. , Couldwell William T.
Published: December 2009

Neurofibromatosis Type 1 (NF1) is a common autosomal dominant disease characterized by complex and multicellular neurofibroma tumors, and less frequently by malignant peripheral nerve sheath tumors (MPNSTs) and optic nerve gliomas. Significant advances have been made in elucidating the cellular, genetic, and molecular biology involved in tumor formation in NF1. Neurofibromatosis Type 1 is caused by germline mutations of the NF1 tumor suppressor gene, which generally result in decreased intracellular neurofibromin protein levels, leading to increased cascade Ras signaling to its downstream effectors. Multiple key pathways are involved with the development of tumors in NF1, including Ras/mitogen-activated protein kinase (MAPK) and Akt/mammalian target of rapamycin (mTOR). Interestingly, recent studies demonstrate that multiple other developmental syndromes (in addition to NF1) share phenotypic features resulting from germline mutations in genes responsible for components of the Ras/MAPK pathway. In general, a somatic loss of the second NF1 allele, also referred to as loss of heterozygosity, in the progenitor cell, either the Schwann cell or its precursor, combined with haploinsufficiency in multiple supporting cells is required for tumor formation. Importantly, a complex series of interactions with these other cell types in neurofibroma tumorigenesis is mediated by abnormal expression of growth factors and their receptors and modification of gene expression, a key example of which is the process of recruitment and involvement of the NF1+/– heterozygous mast cell. In general, for malignant transformation to occur, there must be accumulation of additional mutations of multiple genes including INK4A/ARF and P53, with resulting abnormalities of their respective signal cascades. Further, abnormalities of the NF1 gene and molecular cascade described above have been implicated in the tumorigenesis of NF1 and some sporadically occurring gliomas, and thus, these treatment options may have wider applicability. Finally, increased knowledge of molecular and cellular mechanisms involved with NF1 tumorigenesis has led to multiple preclinical and clinical studies of targeted therapy, including the mTOR inhibitor rapamycin, which is demonstrating promising preclinical results for treatment of MPNSTs and gliomas.
Solitary spinal epidural cavernous angiomas in children presenting with acute neurological symptoms caused by hemorrhage
Authors: Sarikaya-Seiwert Sevgi , Gierga Kristin , Wessalowski Rüdiger , Steiger Hans-Jakob , Hänggi Daniel
Published: December 2009

Spinal solitary epidural cavernous angiomas are rare benign vascular malformations, which occur even less frequently in children than in adults. It is uncommon to find such lesions without adjacent vertebral involvement. Occasionally, these lesions can lead to neurological symptoms through growth or due to intralesional hemorrhage. In this report the authors describe 2 children presenting with acute symptoms and neurological deficits caused by hemorrhage within solitary spinal epidural cavernous angiomas. A 13-year-old girl and a 9-year-old girl, previously healthy, were admitted to the authors' department due to acute radicular pain and neurological deficits. In both cases MR imaging revealed a solitary epidural mass with signs of bleeding and compression of the spinal cord. Complete resection of the lesion via a dorsal approach was performed in both patients. The histological examination of the lesions revealed the characteristic structures of a cavernous angioma with hemosiderin deposits and acute hemorrhage. Both patients recovered fully after surgical removal of the lesions. Review of the literature confirmed that spinal epidural cavernous angiomas are extremely rare in the pediatric patient population, described currently in only 2 instances, but without acute hemorrhage. These cases suggest that epidural cavernous angiomas also have to be considered in the pediatric patient population in the differential diagnosis of intraspinal lesions with acute or progressive neurological symptoms. Microsurgical resection of these cavernous malformations is an effective and curative treatment option.
Efficacy and safety of radical resection of primary and recurrent craniopharyngiomas in 86 children
Authors: Elliott Robert E. , Hsieh Kevin , Hochm Tsivia , Belitskaya-Levy Ilana , Wisoff Jessica , Wisoff Jeffrey H.
Published: December 2009

Object

Optimal treatment of primary and recurrent craniopharyngiomas remains controversial. Radical resection and limited resection plus radiation therapy yield similar rates of disease control and overall survival. The data are much less clear for recurrent tumors. The authors report their experience with radical resection of both primary and recurrent craniopharyngiomas in children and compare the outcomes between the 2 groups.

Methods

A retrospective analysis was performed in 86 children younger than 21 years of age who underwent a total of 103 operations for craniopharyngioma between 1986 and 2008; these were performed by the senior author. The goal was resection with curative intent in all patients. Two patients were lost to follow-up and were excluded from analysis. The mean age at the time of surgery was 9.6 years, and the mean follow-up was 9.0 years.

Results

All 57 children with primary tumors underwent gross-total resection (GTR). A GTR was achieved in significantly fewer children with recurrent tumors (18 [62%] of 29). There were 3 perioperative deaths (3%). Tumor recurred after GTR in 14 (20%) of 71 patients. Overall survival and progression-free survival were significantly better in patients with primary tumors at time of presentation to the authors' institution. There were no significant differences in the neurological, endocrinological, visual, or functional outcomes between patients with primary and those with recurrent tumors. Factors negatively affecting overall survival and progression-free survival include subtotal resection (recurrent tumors only), tumor size ≥ 5 cm, or presence of hydrocephalus or a ventriculoperitoneal shunt. Prior radiation therapy and increasing tumor size were both risk factors for incomplete resection at reoperation.

Conclusions

In the hands of surgeons with experience with craniopharyngiomas, the authors believe that radical resection at presentation offers the best chance of disease control and potential cure with acceptable morbidity. While GTR does not preclude recurrence and is more difficult to achieve in recurrent tumors, especially large and previously irradiated tumors, radical resection is still possible in patients with recurrent craniopharyngiomas with morbidity similar to that of primary tumors.
Primary T-cell lymphoblastic lymphoma of the cavernous sinus
Authors: Sadruddin Sarfaraz , Medeiros L. Jeffrey , DeMonte Franco
Published: December 2009

The rare occurrence of T-cell lymphoblastic lymphoma as a primary tumor in the cavernous sinus is described. The patient, a 17-year-old girl, presented with right-sided ophthalmic and maxillary neuropathy and diplopia due to neuropathies of cranial nerves III and VI. An enhancing mass in the cavernous sinus was identified on MR imaging. Dexamethasone was prescribed but did not provide symptomatic relief. Rapid progression of symptoms led to open biopsy, and a diagnosis of T-cell lymphoblastic lymphoma was made. The patient promptly underwent aggressive chemotherapy in which a modified hyper–cyclophosphamide, vincristine, and dexamethasone without doxorubicin regimen with concurrent radiotherapy was used. The patient achieved complete remission and is currently completing the 2-year maintenance phase of chemotherapy.
Mobile spinal ependymoma
Authors: Moon Karam , Filis Andreas K. , Cohen Alan R.
Published: December 2009

Mobile spinal tumors have been reported previously in the literature, with schwannomas as the most common form. A discrepancy between the location of the tumor in preoperative imaging and its actual position intraoperatively may lead to confusion. The authors present an unusual case of a mobile cauda equina ependymoma. Resection was complicated by cephalad migration of the tumor upon durotomy. Visualization was made possible by engaging a Valsalva maneuver in the patient under anesthesia, at which point the tumor was observed to migrate caudally into the operative field. Observation of this unique pathology is presented as potentially important knowledge for surgeons that might help prevent other unnecessary procedures such as a multilevel laminectomy.
Catheter-tip mass mimicking a spinal epidural hematoma
Authors: Medel Ricky , Pouratian Nader , Elias W. Jeffrey
Published: December 2009

As > 95,000 spinal drug-delivery devices have been implanted since their inception in the 1980s, the recognition of associated adverse effects is essential. Since 1985, numerous reports have described the presence of catheter-tip granulomas. In the current case, the authors describe a less frequent complication of epidural bupivacaine precipitation. Regardless of origin, these unusual lesions have been increasingly recognized as a rare but potentially devastating complication of intrathecal infusions.

A 34-year-old woman with an intrathecal pain-pump delivering fentanyl, bupivacaine, and clonidine for thoracic outlet syndrome presented with rapidly progressive neurological deficits and increasing neck and upper-extremity pain. Neuroimaging disclosed a C7–T1 mass that was thought to be a hematoma that occurred after a recent epidural steroid injection. On emergency surgical decompression by laminectomy, a chalky mass containing viscous fluid was identified surrounding an epidurally located catheter. Histopathological examination revealed a proteinaceous mass consistent with drug precipitate enveloped by fibrosis and mild inflammation. Postoperatively, the patient recovered with minimal neurological deficit. The presentation and clinical relevance are discussed in conjunction with a review of the pertinent literature.

Catheter-tip masses are a rare complication of implantable drug-delivery devices occurring in < 3% of all patients with intrathecal catheters. Regardless of the anatomical site, the most common presenting features are neurological deficits, worsening pain, and increasing requirements for pain medication. Expedient diagnosis and management are essential for physicians treating patients with spinal infusion devices to prevent significant neurological sequelae. Further investigation is warranted regarding the use of bupivacaine as an adjunct in permanent spinal infusion systems.
Revision of transforaminal lumbar interbody fusion using anterior lumbar interbody fusion: a biomechanical study in nonosteoporotic bone
Authors: Ploumis Avraam , Wu Chunhui , Mehbod Amir , Fischer Gustav , Faundez Antonio , Wu Wentien , Transfeldt Ensor
Published: December 2009

Object

Transforaminal lumbar interbody fusion (TLIF) is a popular fusion technique for treating chronic low-back pain. In cases of interbody nonfusion, revision techniques for TLIF include anterior lumbar interbody fusion (ALIF) approaches. Biomechanical data of the revision techniques are not available. The purpose of this study was to compare the immediate construct stability, in terms of range of motion (ROM) and neutral zone (NZ), of a revision ALIF procedure for an unsuccessful TLIF. An in vitro biomechanical comparison of TLIF and its ALIF revision procedure was conducted on cadaveric nonosteoporotic human spine segments.

Methods

Twelve cadaveric lumbar motion segments with normal bone mineral density were loaded in unconstrained axial torsion, lateral bending, and flexion-extension under 0.05 Hz and ± 6-nm sinusoidal waveform. The specimens underwent TLIF (with posterior pedicle fixation) and anterior ALIF (with intact posterior fixation). Multidirectional flexibility testing was conducted following each step. The ROM and NZ data were measured and calculated for each test.

Results

Globally, the TLIF and revision ALIF procedures significantly reduced ROM and NZ compared with that of the intact condition. The revision ALIF procedures achieved similar ROM as the TLIF procedure.

Conclusions

Revision ALIF maintained biomechanical stability of TLIF in nonosteoporotic spines. Revision ALIF can be performed without sacrificing spinal stability in cases of intact posterior instrumentation.
Sagittal whole-spine magnetic resonance imaging in 750 consecutive outpatients: accurate determination of the number of lumbar vertebral bodies
Authors: Hanson Eric H. , Mishra Rahul K. , Chang David S. , Perkins Thomas G. , Bonifield Daniel R. , Tandy Richard D. , Cartwright Peter E. , Peoples Randal R. , Orrison William W.
Published: December 2009

Object

When the number of lumbar and sacral vertebrae is being assessed, variations from typical lumbosacral anatomy may confuse the practitioner, potentially leading to significant clinical errors. In this study, the authors describe the statistical variation in lumbar spine anatomy in an outpatient imaging setting, evaluate the potential implications for clinical practice based on the variation in the number of lumbar-type vertebrae identified, and recommend a method for rapidly determining the number of lumbar spine vertebral bodies (VBs) in outpatients referred for lumbar spine MR imaging.

Methods

A total of 762 patients (male and female) who presented with low back–related medical conditions underwent whole-spine MR imaging in an outpatient setting.

Results

The high-speed whole-spine evaluation was successful for determining the number of lumbar-type VBs in 750 (98%) of 762 consecutive patients. The sagittal whole-spine 3-T MR imaging system images obtained between the beginning of January 2005 and the end of February 2007 were reviewed. The VBs were counted successively from the level of C-2 inferiorly to the intervertebral disc below the most inferior lumbar-type VB. Numbers of disc herniations were also evaluated in the context of the number of VBs.

Conclusions

One in 5 of these outpatients did not have 5 lumbar-type vertebrae: 14.5% had 6; 5.3% had 4; and 1 (0.13%) had the rare finding of 3 lumbar-type vertebrae. Two-thirds of the individuals with 6 lumbar-type vertebrae were male and two-thirds of the individuals with 4 lumbar-type vertebrae were female. Sagittal whole-spine MR imaging can be performed rapidly and efficiently in the majority of patients (98%), and provides improved accuracy for the determination of the number of lumbar-type VBs. A supplementary coronal MR, Ferguson view radiograph or intraoperative fluoroscopic determination for the presence of lumbosacral transitional vertebrae may add additional information when indicated for clinical treatment or surgical planning.
Symptomatic occipitocervical paracondylar process
Authors: McCall Todd , Coppens Jeroen , Couldwell William , Dailey Andrew
Published: December 2009

A paracondylar process is a bony exostosis that arises from the skull base lateral to the occipital condyle and extends inferiorly toward the transverse process of the atlas. This congenital anomaly can vary in size from a small protuberance to an elongated process articulating with an epitransverse process arising from C-1. Typically, a paracondylar process is an incidental finding described in anatomical studies. The authors report on a patient with a symptomatic paracondylar process articulating with an epitransverse process that caused occipitocervical pain. Resection of the paracondylar and epitransverse processes completely relieved the patient's pain.
Surgical challenges associated with the morphology of the spinal accessory nerve in the posterior cervical triangle: functional or structural?
Authors: Tubbs R. Shane , Stetler William , Louis Robert G. , Gupta Ankmalika A. , Loukas Marios , Kelly David R. , Shoja Mohammadali M. , Cohen-Gadol Aaron A.
Published: December 2009

Object

The spinal accessory nerve (SAN) has been reported to have a distinctly coiled appearance in its course through the posterior cervical triangle of the neck. As this is unusual compared with other peripheral nerves including the cranial nerves, the present histological analysis was performed to further elucidate the reason for this anatomy with potential application in nerve injury and repair.

Methods

Ten adult cadavers underwent dissection of the neck. The SAN was harvested proximally and within the posterior cervical triangle. For comparison with other cranial nerves within the neck, the cervical vagus and hypoglossal nerves were also harvested. All nerves underwent histological analysis. Additionally, 2 human fetuses (11 and 20 weeks' gestation) underwent examination of the SAN in the posterior cervical triangle, and 3 randomly selected specimens were submitted for electromicroscopy.

Results

All SANs were found to have a straight gross configuration proximal to the posterior triangle and a coiled appearance within this geometrical area. Histologically, no differences were identified for the SAN in these 2 locations (that is, proximal to and within the posterior cervical triangle). The histology of the SAN both with routine analysis and electron microscopy was similar in both regions and to nerves used as controls (for example, vagus and hypoglossal nerves). Interestingly, both fetal specimens were found to have coiled SANs in the posterior cervical triangle.

Conclusions

Based on this study, it appears that the tortuous course of the SAN in the posterior triangle arises from functional as opposed to structural forces. It is hoped that this analysis will provide some insight into the nature behind the morphology observed in the SAN within the posterior cervical triangle and aid in future investigations regarding its injury. Moreover, such a coiled nature of this nerve may assist the neurosurgeon in identifying it during, for example, neurotization procedures.
Endoscopic third ventriculostomy: outcome analysis in 368 procedures
Authors: Sacko Oumar , Boetto Sergio , Lauwers-Cances Valérie , Dupuy Martin , Roux Franck-Emmanuel
Published: December 2009

Object

Although endoscopic third ventriculostomy (ETV) has been accepted as a procedure of choice for the treatment of obstructive hydrocephalus, the outcome of this treatment remains controversial with regard to age, cause, and long-term follow-up results. The goal of this study was to assess the risk of failure associated with these factors in a retrospective cohort study.

Methods

Between 1999 and 2007, 368 ETVs were performed in 350 patients (165 patients < 18 years of age) with hydrocephalus at the University Hospital of Toulouse. Failure of ETV was defined as cases requiring any subsequent surgical procedure for CSF diversion or death related to hydrocephalus management.

Results

Tumors (53%), primary aqueductal stenosis (18%), and intracranial hemorrhage (13%) were the most common causes of hydrocephalus. The median follow-up period was 47 months (range 6–106 months), and the overall success rate was 68.5% (252 of the 368 procedures). Patients < 6 months of age had a 5-fold increased risk of ETV failure than older patients (adjusted hazard ratio [HRa] 5.0; 95% CI 2.4–10.4; p < 0.001). Hemorrhage-related (HRa 4.0; 95% CI 1.9–8.5; p < 0.001) and idiopathic chronic hydrocephalus (HRa 6.3, 95% CI 2.5–15.0, p < 0.001) had a higher risk of failure than other causes. Most failures (97%) occurred within 2 months of the initial procedure. The overall morbidity rate was 10%, although most complications were minor. Finally, the introduction of ETV in the authors' department reduced the number of shunt insertions and hospital admissions for shunt failures by half and was a source of cost savings.

Conclusions

Endoscopic third ventriculostomy is a safe procedure and an effective treatment option for hydrocephalus. Factors indicating potential poor ETV outcome seem to be very young children and hemorrhage-related and chronic hydrocephalus in adults.
Surgical treatment of a clival-C2 atypical teratoid/rhabdoid tumor
Authors: Heuer Gregory G. , Kiefer Heather , Judkins Alexander R. , Belasco Jean , Biegel Jaclyn A. , Jackson Eric M. , Cohen Marc , O'Malley Bert W. , Storm Phillip B.
Published: December 2009

The authors present the case of en bloc resection of a clival-C2 atypical teratoid/rhabdoid tumor. These aggressive lesions of early childhood generally occur in the cerebellum or cerebral hemispheres. This 7-year-old boy presented with pain on turning his head and was found to have a clival-C2 mass. A metastatic workup was negative for disseminated disease. A transoral biopsy procedure revealed an atypical teratoid/rhabdoid tumor on histological examination. The tumor was resected via a transoral approach, and the patient's spine was stabilized with posterior instrumented fusion from the occiput to C-5. Postoperatively, the patient underwent 16 months of chemotherapy along with 6 weeks of overlapping radiation therapy. Twenty-seven months after the initial surgery he presented with leg pain and was found to have a solitary metastatic lesion at the conus medullaris. There was no local recurrence at the clivus. The conus tumor was resected and found to be consistent with the primary tumor. Several months later the patient presented with disseminated intrathecal disease and ultimately died 42 months after the initial resection.
Anterior encephaloceles in children of Assamese tea workers
Authors: Dutta Hemonta K. , Deori Pradip
Published: December 2009

Object

Anterior encephaloceles are rare congenital malformations. Most of the cases in the literature are reported from Southeast Asia. In India it is seen more frequently among manual laborers in the tea gardens of Assam. A brief background of the patients, clinical presentation, operative treatment, and outcome are discussed, with a review of the relevant literature. The causes and pathogenesis of anterior encephaloceles are discussed. The authors‘ surgical approach to repair of the defect, postoperative complications, and results are described.

Methods

Twenty-eight patients (mean age 38 months, range 1 month–12 years) with anterior encephaloceles who presented between 1998 and 2007 are included in the study. Patients were assessed for physical and psychological growth and development; any associated anomalies were noted. A detailed history of the patient‘s family, including the prenatal history, was obtained. Lesions were classified with the help of neuroimaging studies (skull x-ray, CT, ultrasonography, and MR imaging studies) and confirmed at surgery.

Results

Sixteen patients had nasofrontal, 9 had nasoethmoidal, and 3 had nasoorbital encephaloceles, and 12 patients had associated hydrocephalus. The modes of presentation were nasofrontal swelling, watering from the eyes, CSF leakage, fever, and vomiting. Parents of all the patients were ethnic tea garden workers. The average parental age at the time of marriage was 24 years for men and 18 years for women. Consanguinity was present in 6 patients. Alcohol consumption and tobacco chewing were a common practice in both parents. A total of 42 surgical procedures were done in 16 patients, one of whom died of postoperative meningitis. The mean follow-up duration was 38 months (1–92 months).

Conclusions

Anterior encephaloceles are rare in Western countries and other states in India, but this defect is more commonly seen among the ethnic tea garden workers in Assam. Transcranial repair is the treatment of choice. Unlike encephaloceles in other locations, anterior encephaloceles have a better clinical outcome after surgery.
Hyperemic hydrocephalus: a new form of childhood hydrocephalus analogous to hyperemic intracranial hypertension in adults
Authors: Bateman Grant
Published: December 2009

Object

In the majority of adults with idiopathic intracranial hypertension (IIH), there is an elevation in venous pressure associated with a venous outflow stenosis. In about 15% of IIH patients the elevated venous pressure is associated with an elevation in blood flow but little or no evidence of a stenosis. Venostenotic IIH and idiopathic hydrocephalus in children with a normal blood inflow have been shown to be equivalent. The aim of this study was to test whether children with hydrocephalus and an elevated arterial inflow have a vascular pathophysiology that is analogous to the hyperemic form of IIH in adults.

Methods

Nine children with idiopathic hydrocephalus underwent MR imaging with flow quantification and were found to have arterial inflows 2 SDs above the mean for normal controls. Measurements of the head circumference, ventricular enlargement, total blood inflow, superior sagittal sinus (SSS)/straight sinus (SS) outflow, and the degree of collateral venous flow were performed. The results were compared with findings in 14 age-matched controls.

Results

In hyperemic hydrocephalus the cerebral blood inflow was elevated but the SSS and SS outflows were in the normal range. The sinus outflow as a percentage of the inflow was reduced by 8 percentage points in the SSS territory and 5 percentage points in the SS territory compared with findings in the controls (p = 0.04, p = 0.003, respectively), suggesting blood was returning via collateral channels.

Conclusions

Similar to patients with hyperemic IIH, children with hyperemic hydrocephalus show a significant elevation in collateral venous flow, indicating that the same venous pathophysiology may be operating in both conditions.
A single-center experience with symptomatic postoperative calvarial growth restriction after extended strip craniectomy for sagittal craniosynostosis
Authors: Adamo Matthew A. , Pollack Ian F.
Published: December 2009

Object

Sagittal synostosis accounts for the most common form of craniosynostosis, occurring with an incidence of 1 in 2000–5000 live births. In most cases of single-suture, nonsyndromic sagittal synostosis, a single operation is all that is required to achieve a reasonable cosmetic result. However, there are a number of patients who may experience symptomatic postoperative calvarial growth restriction secondary to fibrosis of newly formed bone and pericranium that replace the surgically removed sagittal suture, or due to fusion of other previously open sutures leading to increased intracranial pressure, necessitating a second operation.

Methods

A retrospective review was conducted of all cases involving infants who had undergone an extended sagittal strip craniectomy with bilateral parietal wedge osteotomies at our institution between 1990 and 2006 for single-suture, nonsyndromic sagittal craniosynostosis. The frequency with which subsequent operations were required for cranial growth restriction was then defined.

Results

There were a total of 164 patients with single-suture nonsyndromic sagittal synostosis. Follow-up data were available for 143 of these patients. The average age at time of initial operation was 5.25 months, and the mean duration of follow-up was 43.85 months. There were 2 patients (1.5%) who required a second operation for symptomatic postoperative calvarial growth restriction.

Conclusions

Recurrence of synostosis with resultant increased intracranial pressure in cases of single-suture, nonsyndromic sagittal craniosynostosis is an uncommon event, but does occur sporadically and unpredictably. Therefore, we recommend routine neurosurgical follow up for at least 5 years, with regular ophthalmological examinations to assess for papilledema.
Noninvasive localization of epileptogenic zones with ictal high-frequency neuromagnetic signals
Authors: Xiang Jing , Wang Yingying , Chen Yangmei , Liu Yang , Kotecha Rupesh , Huo Xiaolin , Rose Douglas F. , Fujiwara Hisako , Hemasilpin Nat , Lee Ki , Mangano Francesco T. , Jones Blaise , deGrauw Ton
Published: December 2009

Object

Recent reports suggest that high-frequency epileptic activity is highly localized to epileptogenic zones. The goal of the present study was to investigate the potential usefulness of noninvasive localization of high-frequency epileptic activity for epilepsy surgery.

Methods

Data obtained in 4 patients, who had seizures during routine magnetoencephalography (MEG) tests, were retrospectively studied. The MEG data were digitized at 4000 Hz, and 3D MR images were obtained. The magnetic sources were volumetrically localized with wavelet-based beamformer. The MEG results were subsequently compared with clinical data.

Results

The 4 patients had 1–4 high-frequency neuromagnetic components (110–910 Hz) in ictal and interictal activities. The loci of high-frequency activities were concordant with intracranial recordings therein 3 patients, who underwent presurgical evaluation. The loci of high-frequency ictal activities were in line with semiology and neuroimaging in all 4 of the patients. High-frequency epileptic activity was highly localized to the epileptogenic zones.

Conclusions

High-frequency epileptic activity can be volumetrically localized with MEG. Source analysis of high-frequency neuromagnetic signals has the potential to determine epileptogenic zones noninvasively and preoperatively for epilepsy surgery.
Cruciate paralysis secondary to traumatic atlantooccipital dislocation
Authors: Sweet Jennifer , Ammerman Joshua , Deshmukh Vivek , White Joseph
Published: December 2009

Cruciate paralysis is a clinical phenomenon thought to result from injury to decussating pyramidal tract fibers at the cervicomedullary junction, producing clinical findings of upper-extremity weakness out of proportion to the lower extremities. The authors present, to their knowledge, the first reported case of cruciate paralysis resulting from atlantooccipital dislocation.
Genome-wide association studies: a powerful tool for neurogenomics
Authors: Cowperthwaite Matthew C. , Mohanty Deepankar , Burnett Mark G.
Published: December 2009

As their power and utility increase, genome-wide association (GWA) studies are poised to become an important element of the neurosurgeon's toolkit for diagnosing and treating disease. In this paper, the authors review recent findings and discuss issues associated with gathering and analyzing GWA data for the study of neurological diseases and disorders, including those of neurosurgical importance. Their goal is to provide neurosurgeons and other clinicians with a better understanding of the practical and theoretical issues associated with this line of research. A modern GWA study involves testing hundreds of thousands of genetic markers across an entire genome, often in thousands of individuals, for any significant association with a particular disease. The number of markers assayed in a study presents several practical and theoretical issues that must be considered when planning the study. Genome-wide association studies show great promise in our understanding of the genes underlying common neurological diseases and disorders, as well as in leading to a new generation of genetic tests for clinicians.
Discovery and Potential of SNP Markers in Characterization of Tunisian Olive Germplasm
Authors: Hakim Imen Rekik , Kammoun Naziha Grati , Makhloufi Emna , Rebaï Ahmed
Published: December 2009

Single Nucelotide Polymorphisms (SNPs) have become the most widely used markers in many current genetic applications. Here we report the discovery of nine new SNPs in olives by direct partial sequencing of two genes (OEX and OEW) in sixteen Tunisian cultivars. The SNP markers were then used to genotype 24 olive cultivars and assess the level of genetic diversity. Power of discrimination of SNP markers was then compared to that of microsatellites (SSRs). A combination of SSR and SNP markers was finally proposed that can be used for cultivars identification in juvenile step or for oil traceability.
Imprecise Shannon’s Entropy and Multi Attribute Decision Making
Authors: Lotfi Farhad Hosseinzadeh , Fallahnejad Reza
Published: January 2010

Finding the appropriate weight for each criterion is one of the main points in Multi Attribute Decision Making (MADM) problems. Shannon’s entropy method is one of the various methods for finding weights discussed in the literature. However, in many real life problems, the data for the decision making processes cannot be measured precisely and there may be some other types of data, for instance, interval data and fuzzy data. The goal of this paper is the extension of the Shannon entropy method for the imprecise data, especially interval and fuzzy data cases.
Characterization of Bronze Surface Layer Formed by Microarc Oxidation Process in 12-Tungstophosphoric Acid
Authors: Mioč Ubavka B. , Stojadinović Stevan , Nedić Zoran
Published: December 2009

This paper is a brief review of our recent research into novel uses for heteropoly compounds as precursors for thin films that can be used as catalysts and materials with good optical, conductive and other characteristics. In view of this, we have chosen thin film obtained with 12-tungsphosphoric acid on aluminum substrates. In all cases, a relatively new, microarc oxidation technique has been used to prepare oxide coatings on substrate surfaces. Advanced physicochemical methods, AFM and SEM-EDS, XRD, Raman and Micro-Raman, and luminescence spectroscopy, as the most powerful techniques, have been used for the characterization of new materials. Possible applications have been discussed as well.
JNK Contributes to Hif-1α Regulation in Hypoxic Neurons
Authors: Antoniou Xanthi , Sclip Alessandra , Ploia Cristina , Colombo Alessio , Moroy Gautier , Borsello Tiziana
Published: December 2009

Hypoxia is an established factor of neurodegeneration. Nowadays, attention is directed at understanding how alterations in the expression of stress-related signaling proteins contribute to age dependent neuronal vulnerability to injury. The purpose of this study was to investigate how Hif-1α, a major neuroprotective factor, and JNK signaling, a key pathway in neurodegeneration, relate to hypoxic injury in young (6DIV) and adult (12DIV) neurons. We could show that in young neurons as compared to mature ones, the protective factor Hif-1α is more induced while the stress protein phospho-JNK displays lower basal levels. Indeed, changes in the expression levels of these proteins correlated with increased vulnerability of adult neurons to hypoxic injury. Furthermore, we describe for the first time that treatment with the D-JNKI1, a JNK-inhibiting peptide, rescues adult hypoxic neurons from death and contributes to Hif-1α upregulation, probably via a direct interaction with the Hif-1α protein.
Synthesis of New Imidazolidin-2,4-dione and 2-Thioxoimidazolidin-4-ones via C-Phenylglycine Derivatives
Authors: De Sousa Luis José Alixandre , Barbosa Filho José Maria , Freitas Lira Bruno , Almeida Medeiros Isac , Soares Lima de Morais Liana Clébia , Dos Santos Alexsandro Fernandes , Soares de Oliveira Cledualdo , De Athayde-Filho Petrônio Filgueiras
Published: December 2009

Hydantoins and their derivatives constitute a group of pharmaceutical compounds with anticonvulsant and antiarrhythmic properties, and are also used against diabetes. N-3 and C-5 substituted imidazolidines are examples of such products. As such, we have developed a synthesis of 2,4-dione and 2-thioxo-4-one imidazolidinic derivatives by reaction of amino acids with C-phenylglycine, phenyl isocyanate and phenyl isothiocyanate. Four amino-derivatives IG(1-4) and eight imidazolidinic derivatives, IM(1-8), were obtained in yields of 70–74%. The mass, infrared, 1H and 13C-NMR spectra of representative products are discussed.
Satellite Remote Sensing in Seismology. A Review
Authors: Tronin Andrew  A.
Published: December 2009

A wide range of satellite methods is applied now in seismology. The first applications of satellite data for earthquake exploration were initiated in the ‘70s, when active faults were mapped on satellite images. It was a pure and simple extrapolation of airphoto geological interpretation methods into space. The modern embodiment of this method is alignment analysis. Time series of alignments on the Earth's surface are investigated before and after the earthquake. A further application of satellite data in seismology is related with geophysical methods. Electromagnetic methods have about the same long history of application for seismology. Stable statistical estimations of ionosphere-lithosphere relation were obtained based on satellite ionozonds. The most successful current project "DEMETER" shows impressive results. Satellite thermal infra-red data were applied for earthquake research in the next step. Numerous results have confirmed previous observations of thermal anomalies on the Earth's surface prior to earthquakes. A modern trend is the application of the outgoing long-wave radiation for earthquake research. In ‘80s a new technology—satellite radar interferometry—opened a new page. Spectacular pictures of co-seismic deformations were presented. Current researches are moving in the direction of pre-earthquake deformation detection. GPS technology is also widely used in seismology both for ionosphere sounding and for ground movement detection. Satellite gravimetry has demonstrated its first very impressive results on the example of the catastrophic Indonesian earthquake in 2004. Relatively new applications of remote sensing for seismology as atmospheric sounding, gas observations, and cloud analysis are considered as possible candidates for applications.
Field Map Reconstruction in Magnetic Resonance Imaging Using Bayesian Estimation
Authors: Baselice Fabio , Ferraioli Giampaolo , Shabou Aymen
Published: December 2009

Field inhomogeneities in Magnetic Resonance Imaging (MRI) can cause blur or image distortion as they produce off-resonance frequency at each voxel. These effects can be corrected if an accurate field map is available. Field maps can be estimated starting from the phase of multiple complex MRI data sets. In this paper we present a technique based on statistical estimation in order to reconstruct a field map exploiting two or more scans. The proposed approach implements a Bayesian estimator in conjunction with the Graph Cuts optimization method. The effectiveness of the method has been proven on simulated and real data.
A Novel Biosensor for Evaluation of Apoptotic or Necrotic Effects of Nitrogen Dioxide during Acute Pancreatitis in Rat
Authors: Jacewicz Dagmara , Dabrowska Aleksandra , Wyrzykowski Dariusz , Pranczk Joanna , Wozniak Michal , Kubasik-Juraniec Jolanta , Knap Narcyz , Siedlecka Kamila , Neuwelt Alexander J. , Chmurzynski Lech
Published: December 2009

The direct and accurate estimation of nitric dioxide levels is an extremely laborious and technically demanding procedure in the molecular diagnostics of inflammatory processes. The aim of this work is to demonstrate that a stop-flow technique utilizing a specific spectroscopic biosensor can be used for detection of nanomolar quantities of NO2 in biological milieu. The use of novel compound cis-[Cr(C2O4)(AaraNH2)(OH2)2]+ increases NO2 estimation accuracy by slowing down the rate of NO2 uptake. In this study, an animal model of pancreatitis, where nitrosative stress is induced by either 3g/kg bw or 1.5 g/kg bw dose of L-arginine, was used. Biochemical parameters and morphological characteristics of acute pancreatitis were monitored, specifically assessing pancreatic acinar cell death mode, NO2 generation and cellular glutathione level. The severity of the process correlated positively with NO2 levels in pancreatic acinar cell cytosol samples, and negatively with cellular glutathione levels.
Reliability and Validity of the Face, Legs, Activity, Cry, Consolability Behavioral Tool in Assessing Acute Pain in Critically Ill Patients
Authors: Voepel-Lewis Terri , Zanotti Jennifer , Dammeyer Jennifer A. , Merkel Sandra
Published: January 2010

Background Few investigators have evaluated pain assessment tools in the critical care setting.

Objective To evaluate the reliability and validity of the Face, Legs, Activity, Cry, Consolability (FLACC) Behavioral Scale in assessing pain in critically ill adults and children unable to self-report pain.

Methods Three nurses simultaneously, but independently, observed and scored pain behaviors twice in 29 critically ill adults and 8 children: before administration of an analgesic or during a painful procedure, and 15 to 30 minutes after the administration or procedure. Two nurses used the FLACC scale, the third used either the Checklist of Nonverbal Pain Indicators (for adults) or the COMFORT scale (for children).

Results For 73 observations, FLACC scores correlated highly with the other 2 scores (ρ = 0.963 and 0.849, respectively), supporting criterion validity. Significant decreases in FLACC scores after analgesia (or at rest) supported construct validity of the tool (mean, 5.27; SD, 2.3 vs mean, 0.52; SD, 1.1; P < .001). Exact agreement and κ statistics, as well as intraclass correlation coefficients (0.67–0.95), support excellent interrater reliability of the tool. Internal consistency was excellent; the Cronbach α was 0.882 when all items were included.

Conclusions Although similar in content to other behavioral pain scales, the FLACC can be used across populations of patients and settings, and the scores are comparable to those of the commonly used 0-to-10 number rating scale.
Monitor Alarm Fatigue: Standardizing Use of Physiological Monitors and Decreasing Nuisance Alarms
Authors: Graham Kelly Creighton , Cvach Maria
Published: January 2010

Background Reliance on physiological monitors to continuously “watch” patients and to alert the nurse when a serious rhythm problem occurs is standard practice on monitored units. Alarms are intended to alert clinicians to deviations from a predetermined “normal” status. However, alarm fatigue may occur when the sheer number of monitor alarms overwhelms clinicians, possibly leading to alarms being disabled, silenced, or ignored.

Purpose Excessive numbers of monitor alarms and fear that nurses have become desensitized to these alarms was the impetus for a unit-based quality improvement project.

Methods Small tests of change to improve alarm management were conducted on a medical progressive care unit. The types and frequency of monitor alarms in the unit were assessed. Nurses were trained to individualize patients’ alarm parameter limits and levels. Monitor software was modified to promote audibility of critical alarms.

Results Critical monitor alarms were reduced 43% from baseline data. The reduction of alarms could be attributed to adjustment of monitor alarm defaults, careful assessment and customization of monitor alarm parameter limits and levels, and implementation of an interdisciplinary monitor policy.

Discussion Although alarms are important and sometimes life-saving, they can compromise patients’ safety if ignored. This unit-based quality improvement initiative was beneficial as a starting point for revamping alarm management throughout the institution.
A Nursing Clinical Decision Support System and Potential Predictors of Head-of-Bed Position for Patients Receiving Mechanical Ventilation
Authors: Lyerla Frank , LeRouge Cynthia , Cooke Dorothy A. , Turpin Debra , Wilson Lisa
Published: January 2010

Background Patients receiving mechanical ventilation are at high risk for pneumonia due to aspiration. Published guidelines recommend elevating the head of the bed 30° to 45°, if not contraindicated, to reduce risk, but this intervention is underused.

Objectives To facilitate incorporating evidence-based practice by improving positioning of patients receiving mechanical ventilation and to identify patient and nurse characteristics that predict use of the guideline.

Methods A modified interrupted time-series design was used. Data were collected on 43 patients and 33 nurses 3 separate times in a 12-bed intensive care unit at a medium-sized hospital. A total of 105 observations were recorded for analysis each time.

Results Mean elevations of the head of the bed increased significantly from phase 1 (27.7°) to phase 2 (31.7°) and from phase 1 to phase 3 (31.1°). Elevations were higher for tube-fed patients than for patients not given enteral tube feedings. Elevations were higher for patients with a pulmonary-related diagnosis and lower for patients with a gastrointestinal diagnosis than for patients with other diagnoses. Elevations were lower for patients with a body mass index between 25.0 and 29.9 (overweight) than for patients with other body mass index values. Nurse characteristics were not significant predictors of elevation.

Conclusion A nursing clinical decision support system integrated into a patient’s electronic flow sheet can increase nurses’ adherence to guidelines. Pulmonary and gastrointestinal diagnoses, body mass index, and tube feeding are predictors of elevation of the head of the bed.