bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cervical osteotomy for the correction of chin-on-chest deformity in ankylosing spondylitis
Authors: Mummaneni Praveen V. , Mummaneni Valli P. , Haid Regis W. , Rodts Gerald E. , Sasso Rick C. 
Published: January 2008

The correction of chin-on-chest deformity is challenging and requires combined anterior and posterior approaches to the cervical spine. The authors describe a cervical osteotomy technique for the correction of chin-on-chest deformity in patients with ankylosing spondylitis (AS). This procedure can be accomplished using a posterior screw rod construct combined with an anterior hybrid plate system.
In patients with AS, a “front-back-front” approach may be necessary because of the deformity's rigidity. The authors describe the complicated intubation and anesthetic requirements for this approach. They performed an anterior discectomy, cervical osteotomy, and unilateral pediculectomy but did not place anterior instrumentation. Via a posterior approach, laminectomies, facetectomies, and the contralateral pediculectomy were then undertaken. A posterior cervical screw/rod system was placed and loosely connected to titanium rods. Intraoperatively the deformity was corrected by placing the neck in extension combined with compression of the posterior screws on the rods. The posterior construct is then tightened. Finally, an anterior cervical approach is performed to place a structural interbody graft and a hybrid anterior cervical plate construct.
The authors have successfully used this approach to correct a chin-on-chest deformity in a patient with ankylosing spondylitis. At 1-year follow-up examination, excellent resolution of the deformity and solid fusion had been achieved. They prefer to perform this procedure by using state-of-the-art anterior and posterior instrumentation systems.
Novel bioabsorbable interbody fusion spacer–assisted fusion for correction of spinal deformity
Authors: Austin Rebekah C. , Branch Charles L. , Alexander Joseph T. 
Published: January 2008

Object
The authors report the cases of 12 patients with medically refractory mechanical low-back pain and intermittent radicular symptoms in whom radiography demonstrated evidence of multilevel lumbosacral degenerative kyphotic and scoliotic deformity and spondylolisthesis.

Methods
These patients underwent multilevel posterior lumbar interbody fusion in which Macropore bioabsorbable spacers were placed. Each patient underwent at least 1 year of clinical and radiographic follow up.

Conclusions
This series illustrates the novel use of bioabsorbable interbody spacers and fusion technique for correction of spinal deformity due to advanced degenerative kyphoscoliosis and spondylolisthesis.
Correction of adult scoliosis via a posterior-only approach
Authors: Lippman Caleb R. , Spence Caple A. , Youssef A. Samy , Cahill David W. 
Published: January 2008

Object
Adult scoliosis is a pathologically different entity from adolescent idiopathic scoliosis. The curves are more rigid, and rotational deformity and multilevel sagittal vertebral slippages compound the coronal malalignment. To correct these deformities, a surgical anterior release procedure is usually required, as well as posterior instrumentation-assisted fusion. This exposes the patient to the risks of a second procedure and of a thoracotomy or laparotomy. To decrease these risks, the authors have performed an anterior release, posterior release, and reduction via a posterior-only approach. The purpose of this study was to analyze quantitatively the degree of pre- and postoperative coronal deformity, the extent of correction, and related complications.

Methods
Data obtained in 20 patients with adult scoliosis were retrospectively studied. Patients presented with persistent back or lower-extremity pain, progressive deformity, or progressive neurological deficit. Sixteen patients underwent Gill-type laminectomy, radical discectomy (including fracture of any anterior and lateral osteophytes), and posterior lumbar interbody fusion (PLIF) of all apical and adjacent segments. One to four anterior release procedures were performed in each patient. Posterior instrumentation was placed over three to 15 levels. Autograft was obtained from the laminectomy sites and posterior iliac crest for fusion. There were no deaths; all patients were followed for a minimum of 1 year. The mean coronal Cobb angle improved from 36° to 14.7°. All spondylolisthetic lesions were reduced to at least Grade I. At the most recent follow-up examination, evidence of fusion was demonstrated in all patients. Reoperation for adjacent-segment failure, cephalad to the highest level of fusion, was required in two cases.

Conclusions
In many cases of adult scoliosis, a satisfactory multiplanar correction may be obtained via a single posterior approach and by using extended PLIF techniques. Cephalad adjacent-segment failure remains a significant problem in patients with osteoporosis, and routine extension of posterior instrumentation to the upper thoracic spine should be considered in these cases.
Okadaic acid–induced apoptosis in malignant glioma cells
Authors: Rami Bimal G. , Chin Lawrence S. , Lazio Barbara E. , Singh Satyendra K. 
Published: January 2008

Object
Okadaic acid (OA), a potent protein phosphatase inhibitor, has been known to induce apoptosis in a variety of cell types. The authors attempted to characterize further this model by identifying proteins involved in this form of programmed cell death.

Methods
Cellular proliferation was assessed using a colorimetric nonradioactive proliferation assay and cell counts. Apoptosis was determined by fluorescent microscopy. Activation of the mitogen-activated protein kinase (MAPK) pathways was determined by immunoprecipitation of extracellular signal–regulated kinase (ERK), c-Jun-n-terminal kinase (JNK), and p38 followed by in vitro kinase assays. Western blot analyses were conducted to show inhibitory-κB (IκB) phosphorylation and degradation as well as Bax upregulation. The binding of nuclear factor–κB (NFκB) was shown by electrophoretic mobility shift assay.
Okadaic acid induced cell death in T98G human malignant cell lines (50% inhibiting concentration = 20–25 nM). In T98G cells YO-PRO fluorescent staining was identified, thus indicating an apoptotic mechanism with a smaller percentage of cells undergoing necrotic cell death. Additionally OA induced JNK and MAPK activities in a time-dependent manner, increased the expression of Bax, and increased IκB phosphorylation and NFκB activation. There was a temporal correlation between these subcellular events and the detection of apoptosis morphology in glioma cells.

Conclusions
The authors believe that OA acts by blocking dephosphorylation events, thus activating apoptotic pathways through ERK and JNK activity. Additionally Bax, IκB and NFκB may also play a role in regulating these pathways.
The Carotid Occlusion Surgery Study
Authors: Grubb Robert L. , Powers William J. , Derdeyn Colin P. , Adams Harold P. , Clarke William R. 
Published: January 2008

The St. Louis Carotid Occlusion Study demonstrated that ipsilateral increased O2 extraction fraction (OEF) (Stage II hemodynamic failure) measured by positron emission tomography (PET) is a powerful independent risk factor for subsequent stroke in patients with symptomatic complete carotid artery (CA) occlusion. The ipsilateral ischemic stroke rate at 2 years has been shown to be 5.3% in 42 patients with normal OEF and 26.5% in 39 patients with increased OEF (p = 0.004). In patients in whom hemispheric symptoms developed within 120 days, the 2-year ipsilateral stroke rates were 12% in 27 patients with normal OEF and 50% in 18 patients with increased OEF. Previous PET studies have demonstrated that anastomosis of the superficial temporal artery (STA) to a middle cerebral artery (MCA) cortical branch can restore OEF to normal.
The authors discuss the undertaking of a study that will test the hypothesis that STA–MCA anastomosis, when combined with the best medical therapy, can reduce ipsilateral ischemic stroke by 40% at 2 years in patients with symptomatic internal CA occlusion and Stage II hemodynamic failure occurring within 120 days after surgery. Only patients with increased OEF distal to a symptomatic occluded CA will be randomized to surgery or medical treatment. The primary endpoint will be all strokes and death occurring between randomization and the 30-day postoperative cut off (with an equivalent period in the nonsurgical group), as well as subsequent ipsilateral ischemic stroke developing within 2 years. It is estimated that 186 patients will be required in each group. Assuming that 40% of PET scans will demonstrate increased OEF, this will require enrolling 930 clinically eligible individuals.
Hypotensive endovascular test occlusion of the carotid artery in head and neck cancer
Authors: Dare Amos O. , Gibbons Kevin J. , Gillihan Matthew D. , Guterman Lee R. , Loree Thom R. , Hicks Wesley L. 
Published: January 2008

Object
To evaluate the reliability of balloon test occlusion with hypotensive challenge (BTO and HC) as a predictor of neurological complications before internal carotid artery (ICA) sacrifice in patients with advanced head and neck cancer, the authors retrospectively reviewed the medical records of patients presenting to their institutions between 1992 and 1997 in whom this preoperative assessment was performed.

Methods
Eleven patents who were candidates for extended comprehensive neck dissection (ECND) and potential ICA sacrifice were included in the study. Eight patients tolerated the test and underwent endovascular occlusion or surgical ligation of the ICA before ECND (four patients), preservation of the ICA at the time of surgery (three patients), or palliative therapy (one patient). Of three patients in whom BTO and HC failed, one patient received palliative treatment only; the other two underwent ECND with preservation of the ICA. In the group of patients who passed the test and underwent ICA occlusion or ligation before ECND, fatal thromboembolic stroke occurred within 24 hours of permanent balloon occlusion in one patient, resulting in a combined neurological morbidity/mortality rate of 25% in this subset of patients and an overall complication rate of 9% in this series.

Conclusions
The authors found that BTO and HC offers a simple and reliable method of preoperative risk assessment when ICA resection is planned for regional control of disease in advanced head and neck cancer. This management option, however, is associated with a potential for neurological complication that must be weighed against the natural course of the disease and the risks and benefits of other treatment modalities.
Extracranial–intracranial bypass for symptomatic occlusive cerebrovascular disease not amenable to carotid endarterectomy
Authors: Tummala Ramachandra P. , Chu Ray M. , Nussbaum Eric S. 
Published: January 2008

Object
The role of cerebral revascularization remains unclear in symptomatic occlusive cerebrovascular disease refractory to medical therapy. Despite the disappointing findings of the Cooperative Study on Extracranial–Intracranial Bypass, a subpopulation of patients with ischemic cerebrovascular disease and poor hemodynamic reserve may benefit from extracranial–intracranial (EC–IC) bypass. The authors reviewed the records of 65 patients who underwent 71 EC–IC bypass procedures at their institution over the past 6 years.

Methods
All patients except one presented with repeated transient ischemic attacks (TIAs) that were referable to the involved vascular region. Eight patients underwent EC–IC bypass urgently for “crescendo” TIAs refractory to anti-platelet and anticoagulation therapy. Indications for surgery included cervical internal carotid artery (ICA) occlusion in 28, supraclinoid ICA stenosis in two, middle cerebral artery stenosis or occlusion in 14, moyamoya disease in 18, and ICA dissection in three. Cerebral angiography demonstrated poor collateral flow to the involved region in each case. There were no postoperative strokes or deaths in this series. Following EC–IC bypass, the vast majority (95.4%) of patients experienced cessation of their ischemic events and stabilization of preexisting neurological dysfunction. Of the eight patients who underwent EC–IC bypass urgently for crescendo TIAs, two awoke with increased neurological deficits that improved rapidly within 24 hours of surgery.

Conclusions
Although the Cooperative Study failed to show benefit from this treatment modality, the authors have continued to perform EC–IC bypass in certain cases. Carefully selected individuals with occlusive cerebrovascular disease and persistent ischemic symptoms refractory to maximal medical therapy appear to benefit from cerebral revascularization.
Molecular genetic analysis of phosphatase and tensin homolog and p16 tumor suppressor genes in patients with malignant glioma
Authors: Abdullah Jafri Malin , Zainuddin Norafiza , Sulong Sarina , Jaafar Hasnan , Isa Mohamad Nizam 
Published: January 2008

Object
Several genes have been shown to carry mutations in human malignant gliomas, including the phosphatase and tensin homolog (PTEN) deleted on chromosome 10 and p16 tumor suppressor genes. Alterations of this gene located on chromosome 10 q23 and 9p21, respectively, may contribute to gliomagenesis. In this study, the authors analyzed 20 cases of malignant gliomas obtained in patients living on the east coast of Malaysia to investigate the possibilities of involvement of the PTEN and p16 genes.

Methods
Samples of DNA were amplified by polymerase chain reaction (PCR), analyzed by single-stranded conformation polymorphism (SSCP), and subsequently by sequencing. Two cases of glioblastoma multiforme, three cases of anaplastic astrocytoma, one case of anaplastic pleomorphic xanthoastrocytoma, and one case of anaplastic ependymoma showed SSCP band shifts in PTEN mutational analyses. The DNA sequencing analyses of these samples revealed missense and nonsense mutations, with cluster of mutations in the region 5' to the core phosphatase motif of exon 5 and the 5'-end of exon 6. No abnormal migration shifts were detected in the glioma samples analyzed for point mutations of the p16 gene. Homozygous deletions of p16 were also not detected in all samples.

Conclusions
These findings indicate that mutations of the PTEN genes were likely to contribute to the tumorigenesis and morphological transformations of gliomas. In addition, the alterations of the p16 gene might not play a major role in tumorigenesis of malignant gliomas in Malaysian patients.
Long-term results of gamma knife surgery for craniopharyngioma
Authors: Kobayashi Tatsuya , Kida Yoshihisa , Hasegawa Toshinori 
Published: January 2008

Object
One hundred seven cases of craniopharyngiomas were treated using gamma knife surgery (GKS) at Komaki City Hospital during the past 12 years. The authors report the long-term results obtained in 100 patients who were followed for 6 to 148 months (mean 65.5 months).

Methods
All patients underwent GKS. The mean tumor diameter and volume were 18.8 mm and 5.8 ml, respectively; lesions were treated with a maximum dose of 21.8 Gy and marginal dose of 11.5 Gy (mean isocenters 4.5). Overall tumor responses were complete in 19, partial in 44, no change in 14, and disease progression in 23, yielding a complete response rate of 19%, overall response rate of 63%, control rate of 77%, and progression rate of 23%. Considering factors such as patient age, nature of the tumor (solid, mixed, cystic), frequency of previous treatments, and tumor size, the age and nature of the tumor were significant prognostic factors.
Changes in neurological and pituitary–hypothalamic symptoms after GKS were evaluated in 91 patients. Overall improvement was demonstrated in 17 (18.7%), no change in 59 (64.8%), and deterioration in 15 (16.5%). Outcome was documented in 93 cases: excellent in 42, good in 23, fair in seven, poor in three, and dead in 18 patients.

Conclusions
Stereotactic GKS is a safe and effective treatment as an adjuvant or boost therapy for postresection residual and/or recurrent craniopharyngiomas; the effects are durable and side effects acceptable.
Use of the Leksell gamma knife C with automatic positioning system for the treatment of meningioma and vestibular schwannoma
Authors: Levivier Marc , Lorenzoni Jose , Massager Nicolas , Ruiz Salvador , Devriendt Daniel , Brotchi Jacques 
Published: January 2008

Object
The authors report their experience using the Leksell gamma knife C (GK-C) for the treatment of meningioma and vestibular schwannoma (VS).

Methods
In December 1999, the first commercially available clinical GK-C was installed at the Université Libre de Bruxelles (Erasme Hospital, Brussels, Belgium). In January 2000, the system was upgraded and equipped with the automatic positioning system (APS). Between February 2000 and February 2003, the APS-equipped GK-C was used to perform 532 radiosurgical treatments, including those in 97 meningiomas and 101 VSs.
Meningioma and VS represent 18 and 19%, respectively, of lesions in patients treated with GK-C at the authors' center. The mean number of isocenters per lesion was 9.5 (range 1–36): 18.1 (range 1–36) for meningioma and 12.8 (range 1–27) for VS. In 77.6% of the cases, the authors used a single helmet of collimators (55.5% in meningioma and 74.3% in VS). The most frequently used collimator size was 4 mm (46.7%). Whereas it was 4 mm in cases of VS (64.3%), it was 8 mm in cases of meningioma (41.6%). The APS could be used in 86% of the cases, either alone (79%) or in combination with trunnions (7%). There was a difference in the APS-based treatment success rate in meningiomas (85%) and VSs (94%). A significant difference was also noted in the conformity of the radiosurgical treatments between the two lesions.

Conclusions
The APS-equipped GK-C represents an evolutionary step in radiosurgery. It requires adjustments by the treating team for its specific limitations, which vary among indications, as exemplified by the differences inherent between meningioma and VS in this series.
Falcotentorial meningiomas: clinical, neuroimaging, and surgical features in six patients
Authors: Quinones-Hinojosa Alfredo , Chang Edward F. , McDermott Michael W. 
Published: January 2008

Object
Meningiomas arising from the falcotentorial junction are rare. As a result, their clinical presentation and surgical management are not well described. During the past 3 years, the authors have treated six patients with falcotentorial meningiomas.

Methods
Most patients presented with symptoms related to raised intracranial pressure, including headaches, papilledema, and visual and gait disturbances. Magnetic resonance imaging revealed a smooth, oval, or round mass, which was typically homogeneously enhancing. Angiography was useful in evaluating arterial supply for embolization, when possible, and determining the status of venous collateral supply and sinus patency. The authors detail the surgical technique used in all six patients. Postoperatively, patients experienced transient cortical blindness, which in all cases spontaneously resolved during the course of several days to weeks. They provide a comprehensive description of the presentation and surgical management of falcotentorial meningiomas.

Conclusions
An excellent outcome can be expected when surgery is predicated on detailed preoperative neuroimaging and knowledge of the nuances of the surgical technique.
Olfactory groove meningiomas
Authors: Hentschel Stephen J. , DeMonte Franco 
Published: January 2008

Object
Olfactory groove meningiomas (OGMs) arise over the cribriform plate and may reach very large sizes prior to presentation. They can be differentiated from tuberculum sellae meningiomas because OGMs arise more anterior in the skull base and displace the optic nerve and chiasm inferiorly rather than superiorly.

Methods
The authors searched the neurosurgery database at the M. D. Anderson Cancer Center for cases of OGM treated between 1993 and 2003. The records of these patients were then reviewed retrospectively for details regarding clinical presentation, imaging findings, surgical results and complications, and follow-up status.
Thirteen patients, (12 women and one man, mean age 56 years) harbored OGMs (mean size 5.7 cm). All patients underwent bifrontal craniotomies and biorbital osteotomies. There were 11 complete resections (including the hyperostotic bone and dura of the cribriform plate and any extension into the ethmoid sinuses) and two subtotal resections with minimal residual tumor left in patients with recurrent lesions. No complication directly due to the surgery occurred in any patient. There were no recurrences in a mean follow-up period of 2 years (range 0–5 years).

Conclusions
With current microsurgical techniques, the results of OGM resection are excellent, with a high rate of total resection and a low incidence of complications. All hyperostotic bone should be removed with the dura of the anterior skull base to minimize the risk of recurrence.
Management of surgical clinoidal meningiomas
Authors: Tobias Samuel , Kim Chang-Hyun , Kosmorsky Gregory , Lee Joung H. 
Published: January 2008

Object
Clinoidal meningiomas remain a major neurosurgical challenge. Surgery-related outcome has been less than desirable in the past, and little attention has been directed toward improving visual deficits. The authors advocate a skull base technique for the removal of these difficult tumors and describe its advantages in terms of improving extent of resection and enhancing overall outcome, particularly visual function.

Methods
A retrospective analysis was performed on data obtained in 26 consecutive patients with clinoidal meningiomas (including one patient with hemangiopericytoma) who underwent resection between June 1995 and January 2003. In 24 cases the skull base procedure involved extradural anterior clinoidectomy, optic canal unroofing, and optic sheath opening; in two cases a standard pterional craniotomy was performed. Fourteen of the 26 patients suffered significant preoperative visual deficits. All patients underwent thorough pre- and postoperative ophthalmological evaluations. The follow-up period ranged from 3 to 91 months (mean 42.3 months). Total resection was achieved in 20 patients (77%), and the majority (76.9%) of patients with preoperative visual impairment experienced significant improvement.

Conclusions
With the use of the skull base technique, total resection and excellent visual outcome may be achieved with minimal morbidity in most patients with clinoidal meningiomas.
Neurotrophic factor in the treatment of Parkinson disease
Authors: Yoo Young Mi , Kim Yong Jung , Lee Uhn , Paik Doo Jin , Yoo Hyun Tae , Park Cheol Wan , Kim Young Bo , Lee Sang Goo , Kim Woo Kyung , Yoo Chan Jong 
Published: January 2008

Object
Parkinson disease (PD) is a well-known degenerative disease resulting in the depletion of dopamine-producing neurons in the pars compacta of the substantia nigra. Adenoviral vector delivery of neurotrophic factors may provide a potential therapy for PD. The authors examined whether glial cell line–derived neurotrophic factor (GDNF) delivered via adenoviral vector (Ad-GDNF) could promote functional recovery in a rat model of PD. Additionally, they examined whether neural precursor cells (NPCs) provide the therapeutic potential of cultured neural cells for cell regeneration and replacement in PD.

Methods
All animals underwent stereotactic injection of 6-hydroxydopamine into the right substantia nigra. Eight weeks later, the rats were tested for apomorphine-induced rotational asymmetry and evaluation of explanted grafts infected with the complementary DNA for GDNF containing NPCs and NPCs alone. In the NPC cultures of embryonic rat striata, the authors found that basic fibroblast growth factor induced the proliferation of stem cells, which give rise to spheres of undifferentiated cells that generate neurons and glia.

Conclusions
In this study the authors found that the reduction of apomorphine-induced rotation was more prominent in parkinsonian rats that received Ad-GDNF-treated grafts containing NPCs (61%) than in those that received grafts of NPCs alone (16%).