bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatment of progressive or recurrent pediatric malignant supratentorial brain tumors with herpes simplex virus thymidine kinase gene vector--producer cells followed by intravenous ganciclovir administration
Authors: Packer Roger J. , Raffel Cory , Villablanca Judith G. , Tonn Jörg-Christian , Burdach Stefan E. , Burger Klaus , LaFond Deborah , McComb J. Gordon , Cogen Philip H. , Vezina Gilbert , Kapcala Leonard P.
Published: January 2008

Object

The outcome for children with recurrent malignant brain tumors is poor. The majority of patients die of progressive disease within months of relapse, and other therapeutic options are needed. The goal of this Phase I study was to evaluate the safety of in vivo suicide gene therapy in 12 children with recurrent, malignant, supratentorial brain tumors.

Methods

After optimal repeated tumor resection, multiple injections of murine vector--producing cells shedding murine replication--defective retroviral vectors coding the herpes simplex virus thymidine kinase type 1 (HSV-Tk1) gene were made into the rim of the resection cavity. Fourteen days after the vector-producing cells were injected, ganciclovir was administered for 14 days. The retroviral vector that was used only integrated and expressed HSV-Tk1 in proliferating cells, which are killed after a series of metabolic events lead to cell death. The median age of the patients was 11 years (range 2--15 years). Treated brain tumors included seven malignant gliomas, two ependymomas, and three primitive neuroectodermal tumors. The patients were treated with one of three escalating dose concentrations of vector-producer cells. Four transient central nervous system adverse effects were considered possibly related to the vector-producing cells. In no child did permanent neurological worsening or ventricular irritation develop, and tests for replication-competent retroviruses yielded negative findings.

Conclusions

This Phase I study demonstrates that in vivo gene therapy in which a replication-defective retroviral vector in murine vector--producing cells is delivered by brain injections can be performed with satisfactory safety in a select group of children with localized supratentorial brain tumors.
Minimally invasive retroperitoneal approach for lumbar corpectomy and reconstruction
Authors: Mühlbauer Manfred , Pfisterer Wolfgang , Eyb Richard , Knosp Engelbert
Published: January 2008

Anterior decompressive surgery with spinal fusion is considered an effective treatment for thoracolumbar fractures and tumors. However, it is also known to be associated with considerable surgical approach–related trauma. The purpose of this study was to show that lumbar corpectomy and spinal reconstruction can be performed via a minimally invasive retroperitoneal (MIR) approach and therefore, the surgical approach–related trauma can be reduced.

The hospital records and radiological studies obtained in five patients (mean age 67.4 years, range 59-76 years) who underwent lumbar corpectomy and spinal fusion via an MIR approach were studied retrospectively. Four patients presented with osteoporotic compression fractures at L-2 and L-3 and one patient with metastatic disease at L-4 from prostate cancer. In all patients neurological deficits due to cauda equina compression were demonstrated.

The MIR approach provided excellent exposure to facilitate complete spinal decompression and reconstruction in all patients, as verified on follow-up x-ray studies. All patients improved clinically. A 1-year follow-up record, available for four patients, showed evidence of continuing clinical improvement and, radiographically, a solid fusion or a stable compound union and anatomically correct reconstruction.

The MIR approach allows anterior lumbar spine surgery to be performed less invasively. The efficacy and safety of this technique compared with the conventional retroperitoneal approach to lumbar spine surgery should be further investigated in a larger series.
Traumatic intracranial aneurysms
Authors: Larson Paul S. , Reisner Andrew , Morassutti Dante J. , Abdulhadi Bassam , Harpring John E.
Published: January 2008

Traumatic intracranial aneurysms are rare, occurring in fewer than 1% of patients with cerebral aneurysms. They can occur following blunt or penetrating head trauma and are more common in the pediatric population. Traumatic aneurysms can be categorized histologically as true, false, or mixed, with false aneurysms being the most common. These aneurysms can present in a variety of ways, but are typically associated with an acute episode of delayed intracranial hemorrhage with an average time from initial trauma to aneurysm hemorrhage of approximately 21 days. The mortality rate for patients harboring these aneurysms may be as high as 50%. Prompt diagnosis based on arteriography and aggressive surgical management are associated with better outcome than conservative treatment. The authors describe a classification scheme for traumatic aneurysms based on their anatomical location and conclude that 1) post-traumatic aneurysm must be considered in patients with acute neurological deterioration following closed head injury; 2) they can occur following mild closed head injury; 3) they occur more commonly in children than in adults; and 4) surgical clipping and/or endovascular occlusion is the definitive treatment.
The influence of cranioplasty on postural blood flow regulation, cerebrovascular reserve capacity, and cerebral glucose metabolism
Authors: Winkler Peter A. , Stummer Walter , Linke Rainer , Krishnan Kartik G. , Tatsch Klaus
Published: January 2008

The indications for cranioplasty after decompressive craniectomy are cosmetic repair and, mainly, restoration of cerebral protection. Although neurological improvement after cranioplasty is repeatedly noted, the reasons for this still remain unclear. Few observations concerning the impact of CSF hydrodynamic and/or atmospheric pressure were published during the last decades. Relevant data concerning the cerebrovascular reserve capacity and cerebral glucose metabolism before and after cranioplasty have been lacking until now. To gain further insight, the present study was undertaken to investigate the impact of cranioplasty on indices of cerebral blood flow regulation and metabolism.

Thirteen patients in whom extensive craniectomies had been performed underwent a meticulous study of blood flow velocities in the middle cerebral artery (MCA) and extracranial internal carotid artery (ICA), as assessed by transcranial Doppler (TCD) ultrasonography during postural maneuvers (supine and sitting positions) and during stimulation with 1 g of acetazolamide for the interpretation of cerebrovascular reserve (CVR) capacity. Twelve patients underwent 18-fluorodesoxyglucose positron emission tomography. These measurements were made before and 7 days after cranioplasty.

Cranioplasty improved preoperative differences in MCA blood flow velocities when comparing the injured with the noninjured hemisphere. Similarly, cranioplasty resolved decreases in extracranial ICA blood flow in the injured hemisphere that were induced by postural changes, which was a constant finding prior to this procedure. More strikingly, however, the CVR capacity, which was severely impaired in both hemispheres, significantly increased after the procedure. Metabolic deficits, which were observed in the injured as compared with the noninjured hemisphere, were found to improve after reimplantation of the skull bone flap.

Cranioplasty appears to affect postural blood flow regulation, CVR capacity, and cerebral glucose metabolism markedly. Thus, early cranioplasty is warranted to facilitate rehabilitation in patients after decompressive craniectomy.
Localization of somatosensory function by using positron emission tomography scanning: a comparison with intraoperative cortical stimulation
Authors: Bittar Richard G. , Olivier André , Sadikot Abbas F. , Andermann Frederick , Comeau Roch M. , Cyr Martin , Peters Terrence M. , Reutens David C.
Published: January 2008

Object

To investigate the utility of [15O]H2O positron emission tomography (PET) activation studies in the presurgical mapping of primary somatosensory cortex, the authors compared the magnitude and location of activation foci obtained using PET scanning with the results of intraoperative cortical stimulation (ICS).

Methods

The authors used PET scanning and vibrotactile stimulation (of the face, hand, or foot) to localize the primary somatosensory cortex before surgical resection of mass lesions or epileptogenic foci affecting the central area in 20 patients. With the aid of image-guided surgical systems, the locations of significant activation foci on PET scanning were compared with those of positive ICS performed at craniotomy after the patient had received a local anesthetic agent. In addition, the relationship between the magnitude and statistical significance of blood flow changes and the presence of positive ICS was examined.

In 22 (95.6%) of 23 statistically significant (p < 0.05) PET activation foci, spatially concordant sites on ICS were also observed. Intraoperative cortical stimulation was positive in 40% of the PET activation studies that did not result in statistically significant activation. In the patients showing these results, there was a clearly identifiable t-statistic peak that was spatially concordant with the site of positive ICS in the sensorimotor area. All PET activation foci with a t statistic greater than 4.75 were associated with spatially concordant sites of positive ICS. All PET activation foci with a t statistic less than 3.2 were associated with negative ICS.

Conclusions

Positron emission tomography is an accurate method for mapping the primary somatosensory cortex before surgery. The need for ICS, which requires local anesthesia, may be eliminated when PET foci with high (> 4.75) or low (< 3.20) t-statistic peaks are elicited by vibrotactile stimulation.
Intrasellar chordomas mimicking pituitary adenoma
Authors: Thodou Eleni , Kontogeorgos George , Scheithauer Bernd W. , Lekka Ioanna , Tzanis Spyros , Mariatos Panagiotis , Laws Edward R
Published: January 2008

Whereas chordomas involving the sellar region are uncommon, largely or entirely intrasellar chordomas are rare. The authors report three cases in which the chordomas filled the pituitary fossa and presented as nonfunctioning pituitary adenomas. All lesions exhibited the typical histological patterns and immunophenotype of chordoma. One tumor, studied ultrastructurally and subjected to DNA analysis, was shown to have a diploid histogram. The authors present a clinicopathological study of these three cases and review the literature on intrasellar chordomas.
A genetic hypothesis for Chiari I malformation with or without syringomyelia
Authors: Speer Marcy C. , George Timothy M. , Enterline David S. , Franklin Amy , Wolpert Chantelle M. , Milhorat Thomas H.
Published: January 2008

In several reports the authors have suggested occasional familial aggregation of syringomyelia and/or Chiari 1 malformation (CM1). Familial aggregation is one characteristic of traits that have an underlying genetic basis. The authors provide evidence for familial aggregation of CM1 and syringomyelia (CM1/S) in a large series of families, establishing that there may be a genetic component to CM1/S in at least a subset of families. The authors observed no cases of isolated familial syringomyelia in their family studies, suggesting that familial syringomyelia is more accurately classified as familial CM1 with associated syringomyelia.

These data, together with the cosegregation of the trait with known genetic syndromes, support the authors' hypothesis of a genetic basis for some CM1/S cases.
Mechanisms underlying the formation and enlargement of noncommunicating syringomyelia: experimental studies
Authors: Stoodley Marcus A. , Jones Nigel R. , Yang Liqun , Brown Christopher J.
Published: January 2008

The pathogenesis of noncommunicating syringomyelia is unknown, and none of the existing theories adequately explains the production of cysts that occur in association with conditions other than Chiari malformation. The authors' hypothesis is that an arterial pulsation–driven perivascular flow of cerebrospinal fluid (CSF) is responsible for syrinx formation and enlargement. They investigated normal CSF flow patterns in 20 rats and five sheep by using the tracer horseradish peroxidase; the effect of reducing arterial pulse pressure was examined in four sheep by partially ligating the brachiocephalic trunk; CSF flow was examined in 78 rats with the intraparenchymal kaolin model of noncommunicating syringomyelia; and extracanalicular cysts were examined using the excitotoxic model in 38 rats.

In the normal animals there was a rapid flow of CSF from the spinal subarachnoid space into the spinal cord perivascular spaces and then into the central canal. This flow ceased when arterial pulsations were diminished. In animals with noncommunicating syringomyelia, there was rapid CSF flow into isolated and enlarged segments of central canal, even when these cysts were causing pressure damage to the surrounding spinal cord. Exitotoxic injury of the spinal cord caused the formation of extracanalicular cysts, and larger cysts were produced when this injury was combined with arachnoiditis, which impaired subarachnoid CSF flow. The results of these experiments support the hypothesis that arterial pulsation–driven perivascular fluid flow is responsible for syrinx formation and enlargement.
The “presyrinx” state: is there a reversible myelopathic condition that may precede syringomyelia?
Authors: Fischbein Nancy J. , Dillon William P. , Cobbs Charles , Weinstein Philip R.
Published: January 2008

Object

Alteration of cerebrospinal fluid (CSF) flow has been proposed as an important mechanism leading to the development of syringomyelia. We hypothesize that a “presyrinx” condition due to potentially reversible alteration in normal CSF flow exists and that its appearance may be due to variations in the competence of the central canal of the spinal cord.

Methods

Five patients with clinical evidence of myelopathy, no history of spinal cord trauma, enlargement of the cervical spinal cord with T1 and T2 prolongation but no cavitation, evidence for altered or obstructed CSF flow, and no evidence of intramedullary tumor or a spinal vascular event underwent MR imaging before and after intervention that alleviated obstruction to CSF flow.

Results

Preoperatively, all patients demonstrated enlarged spinal cords and parenchymal T1 and T2 prolongation without cavitation. Results of magnetic resonance (MR) imaging examinations following intervention in all patients showed resolution of cord enlargement and normalization or improvement of cord signal abnormalities. In one patient with severe arachnoid adhesions who initially improved following decompression, late evolution into syringomyelia occurred in association with continued CSF obstruction.

Conclusion

Nontraumatic obstruction of the CSF pathways in the spine may result in spinal cord parenchymal T2 prolongation that is reversible following restoration of patency of CSF pathways. We refer to this MR appearance as the “presyrinx” state and stress the importance of timely intervention to limit progression to syringomyelia.
The resolution of syringohydromyelia without hindbrain herniation after posterior fossa decompression
Authors: Iskandar Bermans J. , Hedlund Gary L. , Grabb Paul A. , Oakes W. Jerry
Published: January 2008

Object

To provide more information about this rare condition, the authors describe five cases of syringohydromyelia without hindbrain herniation. Preoperative magnetic resonance imaging with and without gadolinium-diethylenetriamine pentaacetic acid revealed no evidence of spinal cord tumor, arachnoiditis, or spinal dysraphism.

Methods

Craniocervical decompression was performed in all patients, after which there was resolution of the symptoms in the four symptomatic patients, and all five showed marked reduction in the size of the syrinx.

Conclusions

The authors hypothesize the rare occurrence of syringohydromyelia resulting from a Chiari-like pathophysiological condition but lacking a hindbrain hernia. Patients with this condition may benefit from craniocervical decompression.
Treatment of terminal syringomyelia in association with tethered cord syndrome: clinical outcomes with and without syrinx drainage
Authors: Erkan Kaan , Unal Faruk , Kiris Talat , Karalar Turan
Published: January 2008

Object

Current use of magnetic resonance (MR) imaging has led to increased awareness of the frequency of terminal syringomyelia in patients with tethered cord syndrome. However, that the surgical treatment of terminal syringomyelia is necessary remains unclear.

In this study the authors attempted to assess the clinical impact, if any, brought after syrinx decompression on the clinical outcome of tethered cord syndrome.

Methods

They randomly assigned 30 cases of pediatric tethered cord into two treatment groups: those in whom an untethering procedure was performed (Group I) and those in whom this procedure was combined with syrinx decompression (Group II). The 1-year follow-up clinical results obtained in the two groups, in correlation with MR imaging findings, were compared to evaluate the benefit of added syrinx drainage.

Clinical follow-up evaluation revealed that surgical drainage of the syrinx, when combined with spinal cord untethering, resulted in better outcomes in terms of resolution of sensory deficits (p = 0.036) and bladder dysfunction (p = 0.05). The improvement in clinical outcome correlated with the radiologically documented resolution of the syrinx cavity; however, response rates of symptoms differed for each tethering subgroup.

Conclusions

Preliminary results of this study indicated that terminal syringomyelia should be considered as a comorbidity that contributes to the clinical outcome of patients with tethered cord syndrome. A better clinical outcome is achieved following successful decompression of the syrinx in addition to untethering the spinal cord. These findings emphasize the importance of recognizing, evaluating, and treating this pathological entity.
Introduction to gene therapy in neurological surgery
Authors: Chen Thomas C. , Helm Gregory A.
Published: January 2008

Gene therapy is an exciting new discipline in which neurosurgery and neurosurgeons can have a direct impact on both patient care and emerging scientific developments. Unlike other organs, the brain is unique in that it has a blood–brain barrier, often preventing efficient systemic gene delivery to the area of interest. Therefore, not only is gene delivery required, but it will often need to be accomplished in a local and specific manner. Although brain neoplasms have been the most commonly studied application of genetic therapeutics in neurological surgery, there are many other potential applications of this technology to neurosurgical disorders, including spinal instability, neurodegenerative disease, neurogenetic diseases, central nervous system (CNS) injury, aneurysms, trauma, stroke, and epilepsy. As the field of gene therapy for the CNS develops from the preclinical setting to clinical trials to mainstream therapy, the need for safe and specific gene delivery will be increasingly apparent. Neurosurgeons are in an enviable position as there is nobody more qualified to address the issue of how a gene can be delivered to the central nervous system. Not only do we have the training to operate on the nervous system and its coverings, but we have the ability to recognize and take care of complications that may arise from these procedures. However, the neurosurgeon's role in gene therapy for the brain and spine should not be confined to gene delivery only. Instead, we also need to understand and have a role in deciding what genes could have therapeutic utility in our patients. Herein lies our challenge in gene therapy: how can we as neurosurgeons interface with our basic science colleagues to address rapidly all of the problems that are blocking the advancement of nucleic acid therapeutics into the clinical setting.
A review of astrocytoma models
Authors: Ding Hao , Nagy Andras , Gutmann David H. , Guha Abhijit
Published: January 2008

Despite tremendous technical improvements in neuroimaging and neurosurgery, the prognosis for patients with malignant astrocytoma remains devastating because of the underlying biology and growth characteristics of the tumor. However, our understanding of the molecular bases of these tumors has greatly increased due to study findings involving operative specimens, astrocytoma predisposing human syndromes, teratogen-induced animal and established human astrocytoma cell lines, and more recently transgenic mouse models. Appropriate small-animal models of spontaneously occurring astrocytomas, which replicate the growth and molecular characteristics found in human tumors, are essential to test the relevance and interactions of these molecular aberrations. In addition, it is hoped that relevant molecular targets will eventually be therapeutically exploited to improve patient outcomes. Appropriate animal models are also essential for testing these novel biological therapies, before they are brought to the clinic, requiring a large investment of time and money. In this paper, various astrocytoma models are discussed, with emphasis on transgenic mouse models that are of great interest to laboratory investigators.
Interaction of fas and fas ligand in a rat 36b10 glioma model
Authors: Ryken Timothy , Frankel Bruce , Longo Sharon , Sibenaller Zita
Published: January 2008

Object

An experimental model of the fas and fas ligand (fasL) interaction in malignant glioma was developed.

Methods

Using plasmid-based delivery, 36B10 rat glioma cells were modified to express fas (36B10-fas), and a delivery fibroblast cell line was modified to produce fasL, resulting in the FR-fasL cell line. Evaluation of fas expression was performed with flow cytometry and expression of fasL confirmed by Western blot analysis. Once the cell lines were created and partially characterized, fas-induced cytotoxicity was evaluated using an antibody-mediated assay for 36B10-fas that demonstrated significant toxicity at 24 and 48 hours. To evaluate the potential for activating the fas molecule by using cell-mediated delivery, coculture cytotoxicity studies were performed with a target cell line (36B10-fas) and effector cell line (FR-fasL). Using a series of culture ratios, increasing cytotoxicity was noted, suggesting that activation of the transfected fas receptor by fasL expression on the carrier cell was occurring.

Conclusion

Based on their experiments, the authors describe a model for evaluating the interaction of fas and fasL in a cellular model of malignant glioma.
Targeted cytotoxic gene delivery to malignant gliomas via the fibroblast growth factor receptor
Authors: Zhu Nian-Ling , Sosnowski Barbara A. , Zlokovic Berislav V. , Ong Michael , Chen Thomas C.
Published: January 2008

Object

The use of gene therapy for the treatment of malignant gliomas has been disappointing. In an effort to increase the viral transduction efficiency in delivering cytotoxic genes to malignant gliomas, the authors have used a novel retargeting schema that redirects the adenovirus to fibroblast growth factor receptors present on the cell surface of both proliferating glioma cells and glioma endothelial cells.

Methods

Using this targeted adenovirus, the authors demonstrated an increase in expression of the luciferase marker gene in human glioma cells and glioma endothelial cells. Transduction with the herpes simplex thymidine kinase gene resulted in greater cytotoxicity when treated with ganciclovir for both cell types. This increased cytotoxity was sustained for up to 6 days after administration of ganciclovir.

Conclusions

The mechanism of cytotoxicity was determined to be apoptosis by using the terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling assay. Increasing the specificity of adenovirus targeting may be crucial to decrease the number of adenoviral vectors necessary to create adequate levels of gene transfer in malignant gliomas, thus reducing the risk of vector-related immunogenicity and toxicity, as well as increasing the overall effectiveness of cytotoxic gene therapy.
Antiplatelet agents, carotid endarterectomy, and perioperative complications
Authors: Worrall Bradford B. , Johnston Karen C.
Published: January 2008

Neurosurgeons are frequently involved in chosing an antiplatelet therapy for their patients in the perioperative period. New data obtained from the Aspirin and Carotid Endarterectomy (ACE) Trial suggest that low-dose aspirin is superior to high-dose aspirin therapy in reducing rates of perioperative stroke and death. The ACE-related data are reviewed, and the authors provide an update on current Food and Drug Administration–approved antiplatelet therapies for secondary stroke prevention, as well as a summary of antiplatelet therapies being developed.
Decompressive craniectomy for space-occupying supratentorial infarction: rationale, indications, and outcome
Authors: Lanzino Desiree J. , Lanzino Giuseppe
Published: January 2008

A subset of patients with ischemic cerebrovascular stroke suffer a progressive deterioration secondary to massive cerebral ischemia, edema, and increased intracranial pressure (ICP). The evolution is often fatal. In these patients, a decompressive craniectomy converts the closed, rigid cranial vault into an “open box.” The result is a dramatic decrease in ICP and a reversal of the clinical and radiological signs of herniation. For these reasons, decompressive craniectomy has been increasingly proposed as a life-saving measure in patients with large, space-occupying hemispheric infarction. The authors review the rationale, indications, and clinical experience with this procedure, which has been performed in patients who have had supratentorial ischemic stroke.
Changes in cerebral blood flow and oxygen metabolism during moderate hypothermia in patients with severe middle cerebral artery infarction
Authors: Keller Emanuela , Steiner Thorsten , Fandino Javier , Schwab Stefan , Hacke Werner
Published: January 2008

Object

Moderate hypothermia has been reported to be effective in the treatment of postischemic brain edema. The effect of hypothermia on cerebral hemodynamics is a matter of controversial discussion in literature. Clinical studies have yet to be performed in patients with ischemic stroke after induction of hypothermia.

Methods

Measurements during mild hypothermia (33–34°C) were made in six patients with severe ischemic stroke involving the middle cerebral artery territory. Hypothermia was induced as soon as possible and maintained for 48 to 72 hours. Cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) were estimated by a new double-indicator dilution method. Measurements of CBF were made during normothermia, immediately after induction of hypothermia, at the end of hypothermia, and after rewarming. A total of 19 measurements of CBF and jugular bulb O2 saturation were made. Immediately after induction of hypothermia, CBF decreased in all patients. During late hypothermia, CBF improved in patients who survived but remained diminished in the two patients who died. Reduced CMRO2 levels were observed during all phases of hypothermia in all but one case.

Conclusions

Preliminary oberservations indicate that moderate hypothermia seems to reduce CMRO2 Immediately after induction of hypothermia, CBF may decrease in all patients. During late hypothermia CBF seems to recover in patients with good outcome but remains diminished in patients who die. Serial bedside CBF measurements with the new double-indicator dilution technique may be useful to describe cerebral hemodynamic characteristics in patients with severe ischemic stroke during hypothermia.
Expression of intracellular adhesion molecule–1 linking superoxide to mobilization of granulocytes and macrophages after periarterial blood in rat femoral artery: effect of rebamipide
Authors: Choi Jae Moon , Kim Chi Dae , Hong Ki Whan
Published: January 2008

Object

To clarify the mechanism(s) involved in the perivascular mobilization of granulocytes and macrophages by periarterial autologous blood (PAAB) in the vicinity of the femoral artery (FA) in rats, superoxide production as well as expression of intercellular adhesion molecule–1 (ICAM-1) were determined by conducting both in vitro and in vivo experiments.

Methods

In an in vitro study, a significant amount of superoxide inhibited by diphenyleneiodonium (20 μM and 100 μM) was identified at 3 hours after application of 10% whole blood to the aortic segments, and these results were correlated with in vitro ICAM-1 expression. High expression of ICAM-1 was subsequently demonstrated in these segments at 24 hours in in vitro and in vivo studies. In the in vivo study, an increased mobilization of granulocytes paralleled with a high expression of ICAM-1 in the vessels at 24 hours after administration of PAAB to the FA and then declined. Subsequently, macrophage infiltration progressively increased at all layers throughout a period of 7 to 12 days. Pretreatment with rebamipide (100 and 300 mg kg−1 day−1, orally) significantly inhibited the expression of ICAM-1 with inhibition of mobilization of granulocyte/macrophage.

Conclusions

These findings suggest that application of PAAB to the rat FA causes superoxide-linked expression of ICAM-1 and mobilization of granulocyte and macrophages. Thus, the potential value in suppressing these variables stimulated by PAAB is indicated in therapeutic strategies for prevention and possible regression of vasospasm after subarachnoid hemorrhage.
Posterior fossa subdural hematoma due to ruptured arteriovenous malformation
Authors: Datta Narendra N. , Chan Kwong Y. , Kwok John C. K. , Poon Christopher Y. F.
Published: January 2008

Patients with cerebellar arteriovenous malformations (AVM) commonly present to the neurosurgical department after having suffered hemorrhages. The subarachnoid space is the usual location for these often repeating episodes of bleedings. In addition, these patients can present with parenchymal hemorrhage. Acute subdural hematoma caused by a ruptured cerebellar AVM is a rare entity and is not generally recognized. The authors present a case of acute posterior fossa subdural hematoma resulting from a ruptured cerebellar AVM.
Evidence-based analysis of odontoid fracture management
Authors: Julien Terrence D. , Frankel Bruce , Traynelis Vincent C. , Ryken Timothy C.
Published: January 2008

Object

The management of odontoid fractures remains controversial. Evidence-based methodology was used to review the published data on odontoid fracture management to determine the state of the current practices reported in the literature.

Methods

The Medline literature (1966–1999) was searched using the keywords “odontoid,” “odontoid fracture,” and “cervical fracture” and graded using a four-tiered system. Those articles meeting selection criteria were divided in an attempt to formulate practice guidelines and standards or options for each fracture type. Evidentiary tables were constructed by treatment type.

Ninety-five articles were reviewed. Five articles for Type I, 16 for Type II, and 14 for Type III odontoid fractures met selection criteria. All studies reviewed contained Class III data (American Medical Association data classification).

Conclusions

There is insufficient evidence to establish a standard or guideline for odontoid fracture management. Given the extent of Class III evidence and outcomes reported on Type I and Type III fractures, a well-designed case-controlled study would appear to provide sufficient evidence to establish a practice guideline, suggesting that cervical immobilization for 6 to 8 weeks is appropriate management. In cases of Type II fracture, analysis of the Class III evidence suggests that both operative and nonoperative management remain treatment options. A randomized trial or serial case-controlled studies will be required to establish either a guideline or treatment standard for this fracture type.
Epidemiolgy of spinal cord injury after acute odontoid fractures
Authors: Harrop James S. , Sharan Ashwini D. , Przybylski Gregory J.
Published: January 2008

Object

Cervical spinal cord injury (SCI) after odontoid fracture is unusual. To identify predisposing factors, the authors evaluated a consecutive series of patients who sustained SCI from odontoid fractures.

Methods

A consecutive series of 5096 admissions to the Delaware Valley Regional Spinal Cord Injury Center were reviewed, and 126 patients with neurological impairment at the C1–3 levels were identified. Seventeen patients had acute closed odontoid fractures with neurological deficit. Various parameters including demographics, mechanisms of injury, associated injuries, fracture types/displacements, and radiographic cervical canal dimensions were compared between “complete” and “incomplete” spinal cord injured–patients as well as with neurologically intact patients who had suffered odontoid fractures. There were similar demographics, mechanisms of injury, associated injuries, fracture type/displacement, and canal dimensions in patients with complete and incomplete SCIs. However, only patients with complete injury were ventilator dependent. In comparison with patients with intact spinal cords, spinal cord–injured patients were more commonly males (p = 0.011) who had sustained higher velocity injuries (p = 0.027). The computerized tomography scans of 11 of 17 neurologically impaired patients were compared with those of a random sample of 11 patients with intact spinal cords. Although the anteroposterior diameter (p = 0.028) and cross-sectional area (p = 0.0004) of the cervical spinal canal at the C–2 level were smaller in impaired patients, the displacement of the fragment was not different.

Conclusions

Odontoid fractures are an infrequent cause of SCI. Patients with these injuries typically are males who have smaller spinal canals and have sustained high velocity injuries.
Closed management of displaced Type II odontoid fractures: more frequent respiratory compromise with posteriorly displaced fractures
Authors: Przybylski Gregory J. , Harrop James S. , Vaccaro Alexander R.
Published: January 2008

Object

Acute respiratory failure has been observed in patients after external immobilization for displaced odontoid fractures. The authors studied the frequency of respiratory deterioration in the acute management of displaced Type II odontoid fractures to identify patients at risk for respiratory failure.

Methods

The authors conducted a retrospective review of a consecutive series of 89 patients with odontoid fractures who were treated over a 5-year period to identify 53 patients with displaced Type II odontoid fractures. Patient demographics, degree of displacement, respiratory status, treatment method, and outcome were examined. Of the 32 patients with posteriorly displaced fractures, 13 experienced acute respiratory compromise, whereas only one of 21 patients with anteriorly displaced fractures had respiratory difficulties (p = 0.0032). The average posterior displacement was 6.9 mm. All 13 were initially managed using flexion traction for reduction of these fractures. Two of these patients died because of failure to emergently secure an airway during closed treatment of the fracture.

Conclusions

Frequent respiratory deterioration during acute closed reduction of posteriorly displaced Type II odontoid fractures was observed, whereas respiratory failure in patients with anteriorly displaced fractures was rare. The use of the flexed cervical position in the setting of retropharyngeal edema rather than the direction of the displacement may substantially increase the risk of respiratory failure. This may prompt early elective nasotracheal intubation during closed reduction of posteriorly displaced Type II odontoid fractures that require a flexed posture.
Use of an osteoconductive agent (Norian) in anterior surgical management of odontoid fractures
Authors: Harrop James S. , Przybylski Gregory J.
Published: January 2008

Odontoid fractures can be successfully treated with anterior screw fixation. Odontoid fractures commonly occur in older patients who may have significant osteopenia. The authors examined the use of a bone substitute to overcome limitations encountered during a procedure in which anterior odontoid screw fixation is performed.

Two elderly patients with displaced, reducible acute odontoid fractures underwent anterior odontoid screw fixation. The intraoperative failure of the anterior vertebral cortex from osteopenic bone and failure to achieve complete contact between the dens and axis were encountered. The defects were supplemented by using the osteoconductive agent Norian. Outcome was evaluated to determine the utility of this method.

Occasional intraoperative failure of anterior odontoid screw fixation may be encountered. Supplementation of bone defects with this osteoconductive agent may facilitate successful bone union in selected patients.
Cerebrospinal fluid leaks following spinal or posterior fossa surgery: use of fat grafts for prevention and repair
Authors: Black Perry
Published: January 2008

Cerebrospinal fluid (CSF) leaks are relatively common following spinal or posterior fossa surgery. A midline dural tear in the spine is readily repaired by direct application of a suture. However, far-lateral or ventral dural tears are problematic. Fat is an ideal sealant because it is impermeable to water. In this paper the author reports his experience with using fat grafts for the prevention or repair of CSF leaks and proposes a technique in which a large sheet of fat, harvested from the patient's subcutaneous layer, is used to cover not only the dural tear(s) but all of the exposed dura and is tucked into the lateral recess. This procedure prevents CSF from seeping around the fat, which may be tacked to the dura with a few sutures. Fibrin glue is spread on the surface of the fat and is further covered with Surgicel or Gelfoam. For ventral dural tears (associated with procedures in which disc material is excised), fat is packed into the disc space to seal off the ventra1 dural leak. Leaks in the posterior fossa are managed similarly to those in the spine. Dural suture lines, following suboccipital or spinal intradural exploration, are prophylatically protected from CSF leakage in the same manner. With one exception, 27 dural tears noted during 1650 spinal procedures were successfully repaired using this technique. There was one case of postoperative CSF leakage in 150 cases in which intradural exploration for tumor or other lesions was undertaken. Both postoperative CSF leaks were controlled by applying additional skin sutures. The use of a fat graft is recommended as a rapid, effective means of prevention and repair of CSF leaks following posterior fossa and spinal surgery.
Review of spinal pseudomeningoceles and cerebrospinal fluid fistulas
Authors: Hawk Mark W. , Kim Kee D.
Published: January 2008

Spinal pseudomeningoceles and cerebrospinal fluid (CSF) fistulas are uncommon extradural collections of CSF that may result from inadvertent tears in the dural–arachnoid layer, traumatic injury, or may be congenital in origin. Most pseudomeningoceles are iatrogenic and occur in the posterior lumbar region following surgery. The true incidence of iatrogenic pseudomeningoceles following laminectomy or discectomy is unknown; however, the authors of several published reports suggest that the incidence of lumbar pseudomeningoceles following laminectomy or discectomy is between 0.07% and 2%. Pseudomeningoceles are often asymptomatic, but patients may present with recurrence of low-back pain, radiculopathy, subcutaneous swelling, or with symptoms of intracranial hypotension. Very rarely, they present with delayed myelopathy. Although magnetic resonance imaging is the neurodiagnostic study of choice, computerized tomography myelography and radionuclide myelographic study may be helpful diagnostic tools in some cases. Analysis of suspect fluid for β2 transferrin may be a useful adjunctive study. Treatment options include close observation for spontaneous resolution, conservative measures such as bed rest and applicaton of an epidural blood patch, lumbar subarachnoid drainage, and definitive surgical repair.
Survival of patients with synchronous brain metastases: an epidemiological study in southeastern Michigan
Authors: Thomas Ajith J. , Rock Jack P. , Johnson Christine C. , Weiss Linda , Jacobsen Gordon , Rosenblum Mark L.
Published: January 2008

Object

It has been suggested that synchronous brain metastases (that is, those occurring within 2 months of primary cancer diagnosis) are associated with a shorter survival time compared with metachronous lesions (those occurring greater than 2 months after primary cancer diagnosis). In this study the authors used data obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program to determine the incidence of synchronous brain metastases and length of survival of patients in a defined population of southeastern Michigan residents.

Methods

Data obtained in 2682 patients with synchronous brain metastases treated from 1973 to 1995 were reviewed. Study criteria included patients in whom at least one brain metastasis was diagnosed within 2 months of the diagnosis of primary cancer and those with an unknown primary source. The incidence per 100,000 increased fivefold, from 0.69 in 1973 to 3.83 in 1995. The most frequent site for the primary cancer was the lung (75.4%). The second largest group (10.7%) consisted of patients in whom the primary site was unknown. The median survival length was 3.3 months. There was no significant difference in the median survival in patients with primary lung/bronchus and those with an unknown primary site (3.2 months and 3.4 months, respectively).

Conclusions

Patients who present with synchronous lesions have a poor prognosis, and the predominant cause of death, in greater than 90% of cases, is related to systemic disease; however, despite poor median survival lengths, certain patients will experience prolonged survival.
Single-stage anterior–posterior decompression and stabilization for complex cervical spine disorders
Authors: Schultz Karl D. , Mclaughlin Mark R. , Haid Regis W. , Comey Christopher H. , Rodts Gerald E. , Alexander Joseph
Published: January 2008

Object

To evaluate the applicability and safety of single-stage combined anterior–posterior decompression and fusion for complex cervical spine disorders, the authors retrospectively reviewed 72 consecutive procedures of this type performed at their respective institutions.

Methods

The indications for decompression and stabilization included: postlaminectomy kyphosis (15 patients), trauma (19 patients), spondylosis and congenital stenosis (32 patients), and ossification of the posterior longitudinal ligament (six patients). All patients underwent anterior cervical corpectomies in which allograft fibula and plates were placed, with 89% of patients undergoing two- or three-level procedures (range one–four levels). Lateral mass plating with autograft (morselized iliac crest) fusion was performed in all patients while the same anesthetic agent was still in effect. A hard cervical collar was used postoperatively in all patients (mean 13 weeks). All patients were followed for a minimum of 2 years (mean 29 months).

Fusion was determined to be successful in all 72 patients (100%). Although the short-term morbidity rate reached 32%, the significant long-term morbidity rate was only 5%. At the 2-year follow-up examination, anterior cervical plate dislodgment was seen in one patient, and 16 of the 516 lateral mass screws implanted were observed to have partially backed out. However, there were no cases of nerve root injury, strut graft extrusion, or anterior plate or screw fracture. There were no clinically significant hardware complications and no patient required repeated operation.

Conclusions

The combined single-stage anterior–posterior decompression, reconstruction, and instrumentation procedure represents a viable option in the treatment of a select group of patients with complex cervical spinal disorders. The technique provides immediate rigid stabilization of the cervical spine, prevents anterior plate failure or strut graft extrusion, and eliminates the need for halo immobilization postoperatively. Furthermore, a higher rate of fusion is achieved with this combined approach than with the anterior approach alone.
Endoscopy-assisted wide-vertex craniectomy, “barrel-stave” osteotomies, and postoperative helmet molding therapy in the early management of sagittal suture craniosynostosis
Authors: Jimenez David F. , Barone Constance M.
Published: January 2008

Object

The purpose of this study was to assess the efficacy, safety, associated complications, and outcome in patients with sagittal suture craniosynostosis in whom endoscopy-assisted wide-vertex craniotomy and “barrel-stave” osteotomy were performed.

Methods

During a 4-year period, 59 patients with sagittal suture synostosis underwent endoscopy-assisted wide-vertex craniectomies, barrel stave–like osteotomies, and postoperatively were fitted with custom-made molding helmets. Data on operative time, blood loss, transfusion rates, hospital length of stay, complications, and hospital charges were collected prospectively. The mean patient age at the time of surgery was 3.7 months. The average blood loss was 31.8 ml; and only one patient required an intraoperative blood transfusion. Nine patients received transfusions of donor blood postoperatively. The mean operative time was 50 minutes, and all but three patients were discharged from the hospital the morning following surgery. There were no intraoperative complications. Normocephaly as well as normal cephalic indices were observed at latest follow up.

Conclusions

The authors conclude that early treatment of infants with sagittal suture craniosynostosis by using minimally invasive, endoscopy-assisted wide-vertex craniectomies provides excellent results and a significantly lower morbidity rate than traditional calvarial vault reconstructive procedures.
Sagittal synostosis
Authors: Jane John A. , Lin Kant Y. , Jane John A.
Published: January 2008

Sagittal synostosis causes predictable malformations depending on the specific suture location that fuses. Anterior fusion causes frontal bossing, whereas posterior fusion causes an occipital knob. Complete sagittal synostosis results in deformity both anteriorly and posteriorly. Variants of each type exist and therefore surgical correction must be tailored to the individual patient. Examples of the different forms of sagittal synotsosis are discussed, and the various surgical techniques available are detailed.
Surgical approach to posterior skull deformity
Authors: Johns Francis R. , Jane John A. , Lin Kant Y.
Published: January 2008

The incidence of occipital skull flattening in infants has recently increased, partly as a result of widespread supine positioning to prevent sudden infant death syndrome. The authors discuss the causes and differential diagnosis of posterior skull deformity in this subpopulation of patients and describe their technique for surgical correction of the condition.
Surgical outcome for thoracic disc surgery in the postlaminectomy era
Authors: Chen Thomas C.
Published: January 2008

In this article the author reviews outcomes of thoracic disc surgery reported in the literature. Care was taken to include only series in which none or a few patients underwent laminectomy for the treatment of thoracic disc lesions. The author found that thoracic discectomy may be performed in an efficacious and safe manner via the transthoracic, lateral extracavitary, transpedicular, or endoscopic approach. In the vast majority of patients, preoperative symptoms of pain (radiculopathy or axial loading pain) and myelopathy were improved after surgery. Measurements of operative time, blood loss, length of hospital stay, and patient satisfaction were often inadequately reported. Complications (systemic and neurological) were well documented and were not common. A plea is made for uniformity in documenting outcome in future series so that today's procedures for thoracic discectomy may be more accurately compared with future cases regardless of the inevitable advances in surgical techniques for removal of thoracic discs.