bluuebunny/crossref_metadata_2025 huggingface dataset:
Intracranial endoscopy
Authors: Schroeder Henry W. S. , Gaab Michael R.
Published: January 2008

The authors' intention is to reduce the invasiveness of intracranial procedures while avoiding traumatization of brain tissue, to decrease the risk of neurological and mental deficits. Intracranial endoscopy is a minimally invasive technique that provides rapid access to the target via small burr holes without the need for brain retraction. Craniotomy as well as microsurgical brain splitting and dissection can often be avoided. Furthermore, because obstructed cerebrospinal fluid pathways can be physiologically restored, the need for shunt placement is eliminated. The ventricular system and subarachnoid spaces provide ideal conditions for the use of an endoscope. Therefore, a variety of disorders, such as hydrocephalus, small intraventricular lesions, and arachnoid and parenchymal cysts can be effectively treated using endoscopic techniques. With the aid of special instruments, laser fibers, and bipolar diathermy, even highly vascularized lesions such as cavernomas may be treated. Moreover, during standard microsurgical procedures, the endoscopic view may provide valuable additional information ("looking around a corner") about the individual anatomy that is not visible with the microscope. In transsphenoidal pituitary surgery, transseptal dissection can be avoided if an endonasal approach is taken. In the depth of the intrasellar space, the extent of tumor removal can be more accurately controlled, especially in larger tumors with para- and suprasellar growth.

The combined use of endoscopes and computerized neuronavigation systems increases the accuracy of the approach and provides real-time control of the endoscope tip position and approach trajectory. In the future, the indications for neuroendoscopy will certainly expand with improved technical equipment.
Combined chest wall resection with vertebrectomy and spinal reconstruction for the treatment of Pancoast tumors
Authors: York Julie E. , Walsh Garrett L. , Lang Frederick F. , Putnam Joe B. , McCutcheon Ian E. , Swisher Stephen G. , Komaki Ritsuko , Gokaslan Ziya L
Published: January 2008

Traditionally, superior sulcus tumors of the lung that involve the chest wall and spinal column have been considered to be unresectable, and historically, patients harboring these tumors have been treated with local radiation therapy with, at best, modest results. The value of gross-total resection remains unclear in this patient population; however, with the recent advances in surgical technique and spinal instrumentation, procedures involving more radical removal of such tumors are now possible. At The University of Texas M. D. Anderson Cancer Center, the authors have developed a new technique for resecting superior sulcus tumors that invade the chest wall and spinal column. They present a technical description of this procedure and results in nine patients in whom stage IIIb superior sulcus tumors extensively invaded the vertebral column. These patients underwent gross-total tumor resection via a combined approach that included posterolateral thoracotomy, apical lobectomy, chest wall resection, laminectomy, vertebrectomy, anterior spinal column reconstruction with methylmethacrylate, and placement of spinal instrumentation. There were six men and three women, with a mean age of 55 years (range 36–72 years). Histological examination revealed squamous cell carcinoma (three patients), adenocarcinoma (four patients), and large cell carcinoma (two patients). The mean postoperative follow-up period was 16 months. All patients are currently ambulatory or remained ambulatory until they died. Pain related to tumor invasion improved in four patients and remained unchanged in five. In three patients instrumentation failed and required revision. There was one case of cerebrospinal leak that was treated with lumbar drainage and one case of wound breakdown that required revision. Two patients experienced local tumor recurrence, and one patient developed a second primary lung tumor. The authors conclude that in selected patients, combined radical resection of superior sulcus tumors of the lung that involve the chest wall and spinal column may represent an acceptable treatment modality that can offer a potential cure while preserving neurological function and providing pain control.
Reoperation for herniated thoracic discs
Authors: Dickman Curtis A. , Rosenthal Daniel , Regan John J.
Published: January 2008

In this review the authors address the surgical strategies required to resect residual thoracic disc herniations. Fifteen patients who had undergone prior thoracic discectomy and who harbored residual or incompletely excised symptomatic thoracic discs were reviewed retrospectively. The surgical procedures that had failed to excise the herniated discs completely included 11 posterolateral approaches, one thoracotomy, and three thoracoscopic procedures. Of the incompletely resected or residual disks 13 were central calcified, two were soft, 12 were extradural, and three were intradural discs. Indications for reoperation were often multiple in each patient and included misidentification of the level of disc disease at the initial operation (five cases), abandoning the procedure because of intraoperative spinal cord injury (three cases), inadequate visualization of the pathology (eight cases), migration of a soft disc fragment within the spinal canal (one case), and intradural disc extension (three cases). The symptoms at the time of reoperation included myelopathy in 13 patients and radicular pain in two. The mean interval before reoperation was 150 days (range 1 day-4 years). The reoperation procedures included one thoracotomy and 14 video-assisted thoracoscopic procedures performed ipsilateral (11 cases) or contralateral (four cases) to the site of the initial surgery.

The herniated disc material was excised completely in all 15 cases without causing new neurological deficits. Reoperation complications included atelectasis in three patients, intercostal neuralgia in two, a loosened screw that required removal in one, and a cerebrospinal fluid leak in one patient. Of the 13 patients who experienced myelopathy preoperatively, 10 recovered neurological function and three stabilized. All patients with radicular pain improved.

Calcified, large, broad-based, centrally located, or transdural thoracic disc herniations can be difficult to resect. These lesions require a ventral operative approach to visualize the dura adequately for a safe and complete resection.
Surgical approaches for the management of idiopathic thoracic scoliosis and the indications for combined anterior-posterior technique
Authors: Rauzzino Michael J. , Shaffrey Christopher I. , Wagner James , Nockels Russ , Abel Mark
Published: January 2008

The indications for surgical intervention in patients with idiopathic scoliosis have been well defined. The goals of surgery are to achieve fusion and arrest progressive curvature while restoring normal coronal and sagittal balance. As first introduced by Harrington, posterior fusion, the gold standard of treatment, has a proven record of success. More recently, anterior techniques for performing fusion procedures via either a thoracotomy or a retroperitoneal approach have been popularized in attempts to achieve better correction of curvature, preserve motion segments, and avoid some of the complications of posterior fusion such as the development of the flat-back syndrome. Anterior instrumentation alone, although effective, can be kyphogenic and has been shown to be associated with complications such as pseudarthrosis and instrumentation failure. Performing a combined approach in patients with scoliosis and other deformities has become an increasingly popular procedure to achieve superior correction of deformity and to minimize later complications. Indications for a combined approach (usually consisting of anterior release, arthrodesis with or without use of instrumentation, and posterior segmental fusion) include: prevention of crankshaft phenomenon in juvenile or skeletally immature adolescents; correction of large curves (75°) or excessively rigid curves in skeletally mature or immature patients; correction of curves with large sagittal-plane deformities such as thoracic kyphosis (> 90°) or thoracic lordosis (> 20°); and correction of thoracolumbar curves that need to be fused to the sacrum. Surgery may be performed either in a staged proceedure or, more commonly, in a single sitting. The authors discuss techniques for combined surgery and complication avoidance.
Gliomas in rodent whisker barrel cortex: a new tumor model
Authors: Sherburn Eric W. , Wanebo John E. , Kim Paul , Song Sheng-Kwei , Chicoine Michael R. , Woolsey Thomas A.
Published: January 2008

Object

Surgical treatment of gliomas is difficult because they are invasive. Invasion of essential cortex often limits or precludes surgical resection. A tumor model was developed in which the rodent whisker barrel cortex was used to examine how gliomas affect cortical function and structure.

Methods

Both DBT (mouse) and C6 (rat) glioma cell lines were grown in culture and labeled with the fluorescent marker Dil in vitro. Labeled tumor cells were then injected into the whisker barrel cortex of adult mice and rats. Neurological assessments were made daily and magnetic resonance (MR) images were obtained. Animals were killed by perfusion 6 to 14 days after injection, and histological sections were prepared and studied.

Tumors were found in all 20 rats and 10 mice that had been injected with the C6 and DBT cell lines, respectively. The animal cells had been labeled with Dil in vitro, and all in vivo tumors proved to be Dil positive. The MR images revealed the tumor locations and serial MR images demonstrated tumor growth. Histological evaluation confirmed the location of the tumor and the disruption of barrel cortex architecture.

Conclusions

Both DBT and C6 glioma cell lines can be used to generate malignant glial tumors reproducibly in the whisker barrel cortex. Fluorescent labeling and cytochrome oxidase staining permit visualization of tumor growth patterns, which disrupt the barrel cortex by microscopic invasion and by gross tissue deformation. Magnetic resonance imaging demonstrates the anatomical extension of these tumors in live rodents. Using this model for further studies on the effects of malignant glioma growth on functional cerebral cortex should advance our understanding of the neurological issues and management of patients with these tumors.
An overview of central nervous system transplantation in human disease
Authors: Breeze Robert E. , Wang Marjorie C.
Published: January 2008

Although its roots date back over a century, the field of neurotransplantation has been shaped mostly by advances over the past 30 years. Animal models of nigrostriatal disconnection in the 1970s allowed investigators to explore the feasibility of neural grafting. By the end of that decade, functional and behavioral effects had been demonstrated using fetal tissue grafts. In the 1980s, animal experimentation continued, as did clinical trials involving patients with idiopathic Parkinson's disease. Both autologous adrenal medullary tissue and fetal allografts were tested in the clinical setting, with the latter proving to yield superior results. Animal models of striatal cell loss provided the impetus for limited clinical trials in patients with Huntington's disease by the early 1990s, and work with both diseases continues today. Although much has been learned, neural grafting remains experimental. Broader applications are being explored even now, though, as transplant techniques are applied to animal models of dementia, spinal cord injury, cortical injury, and pain. Some very limited human trials have already begun in some of these areas. In this review some of the advances in the field are highlighted.
A neural transplantation cannula and microinjector system: experimental and clinical experience
Authors: Mendez Ivar , Hong Murray , Smith Stephen , Dagher Alain , Desrosiers Jacques
Published: January 2008

The authors present a simple, reliable, and safe system for performing neural transplantation in the human brain. The device consists of a transplantation cannula and microinjector system that has been specifically designed to reduce implantation-related trauma and to maximize the number of graft deposits for each injection. The system was evaluated first in an experimental rat model of Parkinson's disease (PD). Animal transplantation with this system showed excellent graft survival with minimal trauma to the brain. Following this experimental stage, the cannula and microinjector system was used in eight patients with PD enrolled in the Halifax Neural Transplantation Program who received bilateral putaminal transplants of fetal ventral mesencephalic tissue. A total of 16 transplantation operations and 64 trajectories were performed in the eight patients, and there were no intra- or perioperative complications. Magnetic resonance imaging studies obtained 24 hours after surgery revealed no evidence of tissue damage or hemorrhage. Transplant survival was confirmed on fluorodopa positron emission tomography scans 6 and 12 months after surgery.

As neural transplantation procedures for the treatment of neurological conditions evolve, the ability to deliver viable grafts safely will become of critical importance. The device presented here has been proven to be of value in maximizing the number of graft deposits while minimizing implantation-related trauma to the host brain.
A pitfall in the diagnosis of child abuse: external hydrocephalus, subdural hematoma, and retinal hemorrhages
Authors: Piatt Joseph H.
Published: January 2008

External hydrocephalus has been associated with subdural hematomas in infancy, and the hematomas have been noted to be secondary to minor trauma or have even been described as spontaneous. The author reports the case of an infant with external hydrocephalus who developed retinal as well as subdural hemorrhages after sustaining a minor head injury. Although retinal hemorrhage in infancy has been considered virtually pathognomonic of child abuse, in the setting of external hydrocephalus a more cautious interpretation may be appropriate.
Thoracoscopic surgical resection of thoracic neurogenic tumors
Authors: Han Patrick P. , Dickman Curtis A.
Published: January 2008

Five patients who harbored large intrathoracic paraspinal neurogenic tumors were treated using thoracoscopic techniques to achieve gross-total tumor resection. All tumors were entirely intrathoracic except one that had an intraspinal extension, and all tumors were treated entirely thoracoscopically except for this one. Gross-total resection was achieved in all cases. The mean clinical follow-up period was 6.8 months. Postoperatively, one patient developed Horner's syndrome. The only other complication was transient intercostal neuralgia (two patients), which has resolved in both patient. No evidence of disease was demonstrated clinically or on follow-up imaging in any patient. Thoracoscopy is an excellent modality with which to treat these tumors, in part because it is associated with significantly less morbidity than open thoracotomy and costotransversectomy procedures. Endoscopic transthoracic approaches reduce the approach-related soft-tissue morbidity by preserving the normal tissues of the chest wall, avoiding rib retraction and muscle transection, reducing postoperative pain, and facilitating recovery. This technique has become the senior author's (C.A.D.'s) surgical approach of choice for the removal of intrathoracic benign paraspinal neurogenic tumors. It has also become the preferred method by which to perform thoracic sympathectomy and remove central, herniated thoracic discs.
Multilevel anterior thoracic discectomies and anterior interbody fusion by using a microsurgical thoracoscopic approach
Authors: Dickman Curtis A. , Mican Camilla A.
Published: January 2008

A video-assisted thoracoscopic microsurgical approach was performed to treat a myelopathic patient with a severe kyphotic deformity caused by chronic nonunion of compression fractures of T7-9 vertebrae. The kyphotic deformity was treated by combined operative procedures. First, an anterior release was performed using a thoracoscopic technique, sectioning the anterior longitudinal ligament and performing multilevel thoracic discectomies. Next, a posterior reduction and internal fixation of the deformity was achieved using hook-rod instrumentation. Finally, bone graft harvested during the posterior approach was used for interbody fusion via a thoracoscopic approach.

Microsurgical thoracoscopic techniques potentially can be used in a variety of spinal surgeries. Compared to transthoracic and posterolateral approaches, this technique presents distinct advantages to treatment of anterior spinal pathology. The small incisions made into the intercostal spaces without retracting the ribs may reduce postoperative pain, shorten the length of hospitalization, and allow early return to activity.

The operative techniques used in this case are described in detail. This report demonstrates that thoracoscopic discectomies and interbody fusion are technically feasible and can be effectively performed with acceptable results.
Applications of positron emission tomography in neurosurgery: past, present, and future
Authors: Polin Richard S. , Lilien David L. , Menendez Jose , Nanda Anil
Published: January 2008

Any novel technological innovation is dependent more on the ingenuity of its users than its inherent properties and potential flaws. Positron emission tomography (PET) is unique in this regard because the limitations of this modality are defined by the ability of its users to identify tracers that will aid in the diagnosis of intracerebral processes. The limitations of PET scanning lay in the extent of tissue resolution and in the currently relatively small number centers equipped to perform PET scanning.

In this issue of Neurosurgical Focus, various applications of PET scanning are detailed. The traditional use of this technology in neurosurgery has been to determine the metabolic nature of cerebral neoplastic lesions so as to help differentiate neoplastic from benign or infectious processes. This determination, however, has not been foolproof, and the technique has been further refined to maximize diagnostic yield.

Nonetheless, the utility of PET scanning continues to grow. New applications have allowed for the precise measurements of cerebral blood flow, helping the neuroscientist understand the functional organization of cortex, the pathophysiology of normal-pressure hydrocephalus, and changes in cerebral blood flow following traumatic injury. Other radiotracers such as fluorodopa allow assessment of the metabolic state of cerebral tissue transplants in restorative neurosurgical procedures.

In this introduction, all of these issues will be considered, and a historical perspective and the potential future uses of this technology will be provided. Technology moves so quickly that new instruments are routinely introduced. The authors will try to assess what properties, in the 25-year history of PET scanning, will need to be improved to keep it as a cutting-edge technology and expand its clinical role.
Comparative genomic hybridization indicating two distinct subgroups of pilocytic astrocytomas
Authors: Szymas Janusz , Wolf Gunther , Petersen Simone , Schluens Karsten , Nowak StanislaW , Petersen Iver
Published: January 2008

Object

The authors investigated the spectrum of chromosomal imbalances of pilocytic astrocytoma by using comparative genomic hybridization (CGH).

Methods

Tumor DNA was extracted from surgically obtained samples of 18 pilocytic astrocytomas that were examined for the presence of neoplastic tissue on frozen sections. Comparative genomic hybridization was performed using standard procedures, and digital image analysis was conducted using out by custom-made software. The chromosomal alterations were determined by a statistical procedure in which Student's t-test (99% confidence interval) was used. Details on CGH analysis and individual ratio profiles are available at http://amba.charite.de/cgh/.

Conclusions

The results suggests the presence of two distinct genetic subgroups of pilocytic astrocytoma, with imbalances of chromosome 19 being the major change for differentiation. In the first group (10 samples), deletions on chromosome 19 were shown as well as multiple gains mainly on chromosomes 5 and 6q but also on chromosomes 4, 7, 8, 10, and 11. The second group (eight samples) was characterized by overrepresentation on chromosomes 19p and 22q, which were associated with deletions on 4q, 5q, 6q, 9p, 13q, and 18q. To understand the diverse biological and clinical behavior exhibited by this tumor type, it is important that pilocytic astrocytomas be classified into distinct subgroups according to their genetic makeup.
Efficacy of anterior odontoid screw fixation in elderly patients with Type II odontoid fractures
Authors: Harrop James S. , Przybylski Gregory J. , Vaccaro Alexander R. , Yalamanchili Kennedy
Published: January 2008

Object

Type II odontoid fractures are the most common trauma-related dens fracture. Although Type III odontoid fractures have a high union rate when external immobilization is applied, Type II fractures are associated with high rates of nonunion, particularly in elderly patients and those with posteriorly displaced fractures or fractures displaced by more than 6 mm. Because elderly patients may not also tolerate external immobilization in a halo vest, alternative techniques should be explored to identify a method for managing these higher-risk patients. In this study the authors examine the efficacy of anterior odontoid screw fixation in a high-risk group of 10 elderly patients (> 65 years of age) treated for Type II odontoid fractures.

Methods

A retrospective review of all patients with Type II odontoid fractures treated at two institutions between September 1997 and March 2000 was performed. Demographic data, neurological examination, fracture type and degree of displacement, treatment method, and outcome data were examined at discharge. Ten patients older than 65 years who had sustained a trauma-related odontoid fracture and had undergone an anterior odontoid screw placement procedure were retrospectively reviewed. Fracture displacement (mean 6.6 mm) was observed in all but one patient, and in seven there were posteriorly displaced fractures. Seven were successfully treated with anterior screw fixation and external orthosis alone; in one patient in whom poor intraoperative screw purchase had been observed, the fracture healed after undergoing halo vest therapy. Only one patient was shown to develop a nonunion requiring a subsequent posterior fusion procedure.

Conclusions

Odontoid screw fixation can be safely performed in elderly patients, and frequent bone union is demonstrated. However, osteopenia may preclude adequate screw fixation in some patients.
Cerebrospinal fluid volume depletion and its emerging clinical/imaging syndromes
Authors: Mokri Bahram
Published: January 2008

Cerebrospinal fluid (CSF) volume depletion, due to CSF leakage or CSF shunt overdrainage, is typically indicated when patients present with orthostatic headaches, with or without several other symptoms: neck or interscapular pain, nausea, emesis, diplopia, changes in hearing, visual blurring, facial numbness or weakness, and radicular upper-limb symptoms. Cerebrospinal fluid pressures typically are quite low and head magnetic resonance images typically reveal diffuse pachy-meningeal gadolinium enhancement, with or without evidence of sagging of the brain and less frequently with subdural fluid collections, enlarged cerebral venous sinuses or pituitary gland or decreased ventricular size.

Magnetic resonance imaging has revolutionized detection of spontaneous CSF leaks, leading to identification of far more cases and recognition of several clinical/imaging forms of presentation of the disorder. These forms, which are different from the “typical” presentation, include a group with consistently normal CSF pressures (normal pressure), another group without abnormal meningeal enhancement (normal meninges), and a group without headache (acephalic). Each of these forms can be seen in a setting of documented and ongoing CSF volume depletion. Awareness of CSF volume depletion is increasing, and its clinical and imaging spectrum is broadening.
Stereotactic radiosurgery in patients with multiple brain metastases
Authors: Chang Steven D. , Lee Elizabeth , Sakamoto Gordon T. , Brown Nalani P. , Adler John R.
Published: January 2008

Object

Patients with multiple brain metastases are often treated primarily with fractionated whole-brain radiation therapy (WBRT). In previous reports the authors have shown that patients with four or fewer brain metastases can benefit from stereotactic radiosurgery in addition to fractionated WBRT. In this paper the authors review their experience using linear accelerator stereotactic radiosurgery to treat patients with multiple brain metastases.

Methods

Fifty-three patients with 149 brain metastases underwent stereotactic radiosurgery. The mean age of patients was 53.1 years (range 20–78 years). There were 23 men and 30 women. The primary tumor location was lung (27 patients), melanoma (10), breast (six), ovary (six), and other (four). All patients harbored at least two metastatic tumors treated with radiosurgery; 27 patients (51%) harbored two lesions, 17 (32%) three lesions, eight (15%) four lesions, and one patient (2%) harbored five lesions. The mean radiation dose administered was 19.6 Gy (range 14–30 Gy), and the mean secondary collimator size was 15.7 mm (range 7.5–40 mm). One hundred thirty-two (89%) of the 149 treated tumors were available for review on magnetic resonance (MR) imaging at 3 months posttreatment. Fifty-two percent were smaller in size, 31% were stable, 9% had increased in size, and 8% had disappeared. New metastatic tumors appeared in 12 (23%) of the 53 patients on MR imaging within 6 months posttreatment. Radiation-induced necrosis occurred at the site of eight (5.4%) of the 149 tumors at 6 months. Seven tumors (4.7%) subsequently required surgical resection for either tumor progression (four cases) or worsening edema from radiation-induced necrosis (three cases). Median actuarial survival was 9.6 months.

Conclusions

Stereotactic radiosurgery can be used to treat patients with up to four brain metastases with a 91% rate of either decrease or stabilization in tumor size and a low rate of radiation-induced necrosis. In the authors' study only a small number of patients subsequently required surgical resection of a treated lesion.
Current treatment of patients with multiple brain metastases
Authors: Chang Steven D. , Adler John R.
Published: January 2008

The management of patients with multiple brain metastases remains a difficult challenge for neurosurgeons. This patient population has a poor prognosis when compared with those harboring a solitary brain metastasis, and historically treatment has generally consisted of administering whole-brain radiotherapy once the diagnosis of multiple brain metastases is made. Resection can be useful in a subset of patients with multiple metastases in whom one or two of the lesions are symptomatic, as this may provide rapid reduction of mass effect and edema. Furthermore, the authors of recent studies have shown that stereotactic radiosurgery can be used in certain patients with multiple brain metastases as part of the treatment regimen. In this review the authors outline the treatment options and indications as well as a management strategy for the treatment of patients with multiple brain metastases.
Endoscopic thoracic discectomy
Authors: Patrick Johnson J. , Filler Aaron G. , McBride Duncan Q.
Published: January 2008

Object

Thoracoscopic discectomy is a minimally invasive procedure simulating a thoracotomy and is an alternative to the costotransversectomy and transpedicular approaches. In recent studies authors have concluded that thoracoscopic discectomy is the preferred procedure; however, relative historical comparisons were difficult to interpret.

The authors conducted a prospective nonrandomized study in which they compared data on 36 patients undergoing thoracoscopic discectomy with eight patients undergoing thoracotomy between 1995 and 1999.

Methods

Patients affected with one- or two-level lesions underwent a thoracoscopic discectomy, and patients with three-level lesions or more underwent thoracotomy and discectomy. Data were collected on operative time, blood loss, chest tube duration, narcotic agent use, and hospital length of stay (LOS). Longer-term follow-up study of pain-related symptoms and neurological function was conducted.

Patients who underwent thoracoscopic discectomy had shorter operative times, less blood loss, a shorter period of chest tube drainage dependence, less narcotic usage, and a shorter LOS. These findings were statistically significant (p < 0.05) for narcotic usage and shorter LOS. Pain related to radiculopathy was improved by means of 75%, and no patients exprienced worsened pain. In patients with myelopathy there was an improvement of two Frankel grades in the thoracoscopic group and one Frankel grade in the thoracotomy discectomy group, but patients in the thoracotomy group were significantly worse preoperatively. One myelopathic patient from each group suffered a worsened outcome postoperatively, although this was not attributed to the method of surgery. The incidence of complications (minor and major) was 31% in the thoracoscopic group and greater than 100% (that is, more than one complication per patient) in the thoracotomy/discectomy group.

Conclusions

One advantage to thoracoscopic discectomy is its reduced incidence of morbidity compared with thoractomy, but its steep learning curve and unfamiliar surgical techniques make this procedure less practical for surgeons not performing it frequently. The more familiar costotransversectomy, transpedicular, and thoracotomy procedures remain viable alternatives for surgeons more experienced in these procedures.
Laminectomy for thoracic spinal canal stenosis
Authors: Kalfas Iain H.
Published: January 2008

Stenosis of the thoracic spinal canal is a relatively rare disorder with numerous causes. Clinical manifestations include signs and or symptoms consistent with focal thoracic radiculopathy and/or myelopathy. Several surgical approaches for the decompression of the stenotic thoracic canal have been described. Laminectomy is typically reserved for only those cases in which dorsal compression of the neural elements is demonstrated; it is contraindicated when the epidural compression is primarily ventral in location.
Treatment of thoracic disc herniation: evolution toward the minimally invasive thoracoscopic technique
Authors: Burke Timothy G. , Caputy Anthony J.
Published: January 2008

Thoracic disc herniation has always carried with it the potential for serious adverse neurological consequences if not treated appropriately. The authors review the historical evolution of treatment for thoracic disc herniation from the early surgical series using dorsal approaches (which were known to involve a significant risk of paraplegia) to later surgical series in which lateral and then ventral approaches to the disc were increasingly emphasized, with significant improvement in patient outcome.

The evolution of minimally invasive thoracoscopic techniques is discussed, together with the results of several surgical series demonstrating significant reductions in morbidity compared with more traditional methods. The technique of thoracoscopic discectomy is presented in detail.
Adoptive immunotherapy in patients with recurrent malignant glioma: preliminary results of using autologous whole-tumor vaccine plus granulocyte-macrophage colony–stimulating factor and adoptive transfer of anti-CD3–activated lymphocytes
Authors: Sloan Andrew E. , Dansey Roger , Zamorano Lucia , Barger Geoffrey , Hamm Caroline , Diaz Fernando , Baynes Roy , Wood Gary
Published: January 2008

Object

This trial was designed to determine the ability of autologous whole–tumor cell vaccines to induce cell-mediated immune responses in patients with recurrent malignant glioma, as well as to determine whether combining such vaccination with adoptive transfer of in vitro activated T lymphocytes prolongs patient survival.

Methods

Nineteen patients with recurrent malignant glioma, in whom previous external beam radiotherapy and at least one course of chemotherapy had failed were vaccinated twice with irradiated autologous whole tumor cells by using granulocyte-marcrophage colony–stimulating factor as an adjuvant. Patients then underwent leukapheresis followed by adoptive transfer of peripheral blood lymphocytes activated in vitro with anti-CD3 and interleukin-2. In vivo immune response, radiological response, clinical outcome, and survival were monitored.

Seventeen patients developed a delayed-type hypersensitivity (DTH) response to vaccination that appeared to be directed against the autologous tumor. In eight patients there was radiological evidence of a response and in five there was evidence of clinical improvement. Median survival was 12 months (range 6–28 months), and both the presence of a DTH response and the radiological response correlated with survival (p < 0.02 and p < 0.04, respectively).

Conclusions

These preliminary results suggest that autologous whole–tumor cell vaccines induce a cell-mediated immune response, which appears to be tumor specific in most patients. Furthermore, vaccination combined with adoptive immunotherapy with in vitro activated cells may induce a radiologically demonstrated tumor response and improved survival despite a condition of advanced disease and immunosuppression resulting from previous treatment or tumor burden. Further studies of immunotherapy are warranted.
Subgaleal shunting: A 20-year experience
Authors: Savitz Martin H. , Malis Leonard I.
Published: January 2008

Object

The authors undertook a retropective study to evaluate the effectiveness of diverting intracranial fluid into the subgaleal space for temporary absorption by the membranes of the scalp.

Methods

Eighty-one patients were treated over a 20-year period. There were 22 cases of hypertensive hydrocephalus, 52 cases of acute head trauma, and seven cases of chronic subdural hematoma. The simple surgical technique is described.

Subgaleal shunting provided effective short-term treatment of hydrocephalus and increased intracranial pressure, which was monitored directly in 22 cases of cerebral contusion and edema.

Conclusions

The closed method for drainage of cerebrospinal fluid avoids the complications of open ventriculostomy or open drainage of the subdural space.
Practice parameters for the management of single brain metastasis
Authors: Rock Jack P. , Haines Stephen , Recht Lawrence , Bernstein Mark , Sawaya Raymond , Mikkelsen Tom , Loeffler Jay
Published: January 2008

Object

In January 1998 the Guidelines and Outcomes Committee of the American Association of Neurological Surgeons (AANS) issued a charge for the development of evidence-based practice parameters focusing on the treatment of patients with single metastasis to the brain. The charge was imposed in response to the significant controversy surrounding questions relating to the optimal management strategies for patients with single brain metastasis.

Methods

A team consisting of physicians from the AANS, the American Academy of Neurology, and the American Association of Therapeutic Radiation Oncology convened and the literature was reviewed. Methodically drawing from the best of Class I, II, and III levels of available evidence, authors sought to determine how the literature addressed and disposed of the question of the optimal management for an adult with a known history of cancer and a single meta-static brain lesion. Framing the question in this specific manner allowed researchers to focus directly on treatment issues, without having to consider diagnostic issues.

Conclusions

The results of the evidence-based analysis demonstrated that there was insufficient information to establish standards of care. Data from the literature does, however, support a guideline stating that surgical resection accompanied by whole brain radiation therapy is associated with the best survival rate. Additional lower-quality evidence supports an option for management with radiosurgery.
Recombinant adenovirus-transduced dendritic cell immunization in a murine model of central nervous system tumor
Authors: Broder Howard , Anderson Andrea , Odesa Sylvia K. , Kremen Thomas J. , Liau Linda M.
Published: January 2008

Object

Dendritic cells (DCs) are potent antigen-presenting cells that have been shown to play a critical role in the initiation of host immune responses against tumor antigens. In this study, a recombinant adenovirus vector encoding the melanoma-associated antigen, MART-1, was used to transduce murine DCs, which were then tested for their ability to activate cytotoxic T lymphocytes (CTLs) and induce protective immunity against B16 melanoma tumor cells implanted intracranially.

Methods

Genetic modification of murine bone marrrow–derived DCs to express MART-1 was achieved through the use of an E1-deficient, recombinant adenovirus vector (AdVMART1). Sixty-two C57BL/6 mice were immunized by subcutaneous injection of AdVMART-1-transduced DCs (23 mice), untransduced DCs (17 mice), or sterile saline (22 mice). Using the B16 murine melanoma, which naturally expresses the MART-1 antigen, all the mice were then challenged intracranially with viable, unmodified syngeneic B16 tumor cells 7 days later. Splenocytes obtained from representative animals in each group were harvested for standard cytotoxicity and enzyme-linked immunospot assays. The remaining mice were followed for survival.

Immunization of C57BL/6 mice with DCs transduced with AdVMART1-DC elicited the development of antigen-specific CTL responses. As evidenced by a prolonged survival curve when compared with control-immunized mice harboring intracranial B16 tumors, AdMART1-DC vaccination was able to elicit partial protection against central nervous system (CNS) tumor challenge in vivo. However, this CNS antitumor immunity was weaker than that previously demonstrated against subcutaneous B16 tumors in which the same vaccination strategy was used.

Conclusions

These data suggest that immune responses generated against CNS tumors by DC-based vaccines may be different from those obtained against subcutaneous tumors.
Diastematomyelia and spinal teratoma in an adult
Authors: Elmacı İlhan , Dağçinar Adnan , Özgen Serdar , Ekinci Gazanfer , Pamir M. Necmettin
Published: January 2008

Diastematomyelia, or split cord malformation, a complete or incomplete sagittal division of the neural axis into halves, is seen in association with many other congenital anomalies. Among these anomalies, intradural spinal teratoma is extremely rare. Diastematomyelia is a well-recognized although unusual clinical syndrome in children, but it is rarely reported in the adult. The authors describe a 42-year-old man who presented with pain and distal left-leg weakness as well as neurogenic claudication for 1 month. The patient underwent radiological examinations, and diastematomyelia and an intradural lumbar teratoma were diagnosed. He underwent surgery and was followed for 1 year. This is the fourth case of an adult who simultaneously presented with diastematomyelia and an intradural teratoma.
Comparison of intraoperative MR imaging and 3D-navigated ultrasonography in the detection and resection control of lesions
Authors: Tronnier Volker M. , Bonsanto Matteo M. , Staubert Andreas , Knauth Michael , Kunze Stefan , Wirtz Christian R.
Published: January 2008

Object

The authors undertook a study to compare two intraoperative imaging modalities, low-field magnetic resonance (MR) imaging and a prototype of a three-dimensional (3D)–navigated ultrasonography in terms of imaging quality in lesion detection and intraoperative resection control.

Methods

Low-field MR imaging was used for intraoperative resection control and update of navigational data in 101 patients with supratentorial gliomas. Thirty-five patients with different lesions underwent surgery in which the prototype of a 3D-navigated ultrasonography system was used. A prospective comparative study of both intraoperative imaging modalities was initiated with the first seven cases presented here.

In 35 patients (70%) in whom ultrasonography was performed, accurate tumor delineation was demonstrated prior to tumor resection. In the remaining 30% comparison of preoperative MR imaging data and ultrasonography data allowed sufficient anatomical localization to be achieved. Detection of metastases and high-grade gliomas and intra-operative delineation of tumor remnants were comparable between both imaging modalities. In one case of a low-grade glioma better visibility was achieved with ultrasonography. However, intraoperative findings after resection were still difficult to interpret with ultrasonography alone most likely due to the beginning of a learning curve.

Conclusions

Based on these preliminary results, intraoperative MR imaging remains superior to intraoperative ultrasonography in terms of resection control in glioma surgery. Nevertheless, the different features (different planes of slices, any-plane slicing, and creation of a 3D volume and matching of images) of this new ultrasonography system make this tool a very attractive alternative. The intended study of both imaging modalities will hopefully allow a comparison regarding sensitivity and specificity of intraoperative tumor remnant detection, as well as cost effectiveness.
Intraoperative microvascular Doppler monitoring of blood flow within a spinal dural arteriovenous fistula: a precious surgical tool
Authors: Iacopino Domenico Gerardo , Giusa Maria , Conti Alfredo , Cardali Salvatore , Tomasello Francesco
Published: January 2008

The authors describe a case of spinal arteriovenous fistula (AVF) treated by a microvauscular Doppler–assisted surgical interruption of the arterialized vein. Microvascular Doppler monitoring represents a valid, widely available, non-invasive tool that enables identification, through flow spectrum analysis, of components of this type of vascular malformation. In this case because the location of the fistula was identified prior to opening the dura only minimally invasive surgery was required. Direct recordings of the arterialized draining vein and the nidus of the fistula demonstrated a pathological spectrum caused by the arterial supply and the disturbed venous outflow in which a high-resistance flow pattern and low diastolic flow resembling an arterial-like flow velocity were observed. The fistula was obliterated by interruption of the draining vein, and Doppler measurements provided information on flow velocity changes in the medullary veins from an arterial to a venous pattern. The absence of any residual flow in the AVF confirmed successful hemodynamic treatment.

Intraoperative microvascular Doppler recording during surgical closure of spinal AVF is a widely available and reliable monitoring modality that helps to produce excellent clinical results.
Surgical Interbody Research Group–radiographic assessment of interbody fusion devices: fusion criteria for anterior lumbar interbody surgery
Authors: Burkus J. Kenneth , Foley Kevin , Haid Regis , LeHuec Jean-Charles
Published: January 2008

The authors present their radiographic criteria for assessing fusion of the lumbar spine after anterior interbody fusion with intradiscal implants. These criteria include the assessment of plain radiographs, dynamic motion radiographs, and thin-cut computerized tomography scans. Fusion within the instrumented spinal motion segment can be determined using radiographic evaluation to assess spinal alignment on sequential examinations, angular and translational changes on dynamic motion studies, and device–host interface, and to identify new bone formation and bone remodeling. Finally, to aid the clinician in assessing fusion, the authors describe the five zones of fusion within the intervertebral disc space.
Bone graft substitutes for the promotion of spinal arthrodesis
Authors: Helm Gregory A. , Dayoub Hayan , Jane John A.
Published: January 2008

In the prototypical method for inducing spinal fusion, autologous bone graft is harvested from the iliac crest or local bone removed during the spinal decompression. Although autologous bone remains the “gold standard” for stimulating bone repair and regeneration, modern molecular biology and bioengineering techniques have produced unique materials that have potent osteogenic activities. Recombinant human osteogenic growth factors, such as bone morphogenetic proteins, transforming growth factor–β, and platelet-derived growth factor are now produced in highly concentrated and pure forms and have been shown to be extremely potent bone-inducing agents when delivered in vivo in rats, dogs, primates, and humans. The delivery of pluripotent mesenchymal stem cells (MSCs) to regions requiring bone formation is also compelling, and it has been shown to be successful in inducing osteogenesis in numerous pre-clinical studies in rats and dogs. Finally, the identification of biological and nonbiological scaffolding materials is a crucial component of future bone graft substitutes, not only as a delivery vehicle for bone growth factors and MSCs but also as an osteoconductive matrix to stimulate bone deposition directly. In this paper, the currently available bone graft substitutes will be reviewed and the authors will discuss the novel therapeutic approaches that are currently being developed for use in the clinical setting.
Surgery for orbital tumors. Part II: transorbital approaches
Authors: Cockerham Kimberley P. , Bejjani Ghassan K. , Kennerdell John S. , Maroon Joseph C.
Published: January 2008

Orbital tumors can be excised or biopsy samples obtained via transorbital approaches, especially those located in the anterior two thirds of the orbit. The indications and various surgical steps will be reviewed for the anterior, the anteromedial, and the lateral approaches. Some of these approaches can be combined or extended to accommodate large or deep-seated tumors.
The historical development of the pseudotumor concept
Authors: Johnston Ian
Published: January 2008

The author outlines the history of the development of the pseudotumor concept, first specifically formulated by Nonne in 1904 but implicit in earlier descriptions. A scheme of periodization is applied, identifying otological, neurosurgical, neurological, and neuroophthalmological periods; he relates theoretical and practical developments in the understanding of the condition to the concerns of the dominant speciality involved in diagnosis and management. Key studies from each period are discussed in relation to the issues of mechanism, origin, nomenclature, diagnosis, and treatment. During the otological period, approaches to the condition were heavily influenced by its common association with middle ear infection, often with venous sinus involvement, and this led to the idea of disturbed cerebrospinal fluid dynamics as the cause. The advent of neuroradiological systems ushered in the neurosurgical period in which the significant but unfinished debate began: which intracranial compartment is primarily implicated in the intracranial hypertension? By the time of the neurological period cerebral edema was implicated as the cause, and this coincided with the availability of appropriate treatment methods and steroidal and diuretic agents. Toward the end of this period additional major advances in investigative methods again brought the issue of mechanism into contention, although a resolution was not to follow. The neuroophthalmological period is characterized by an increased awareness of the significance of visual loss and a return to one of the original methods of treatment. Finally, the possible significance of impaired cranial venous outflow, a thread running through all periods, is considered.