bluuebunny/crossref_metadata_2025 huggingface dataset:
Temporal changes in intracranial pressure in a modified experimental model of closed head injury
Authors: Engelborghs Koen , Verlooy Jan , Van Reempts Jos , Van Deuren Bruno , Van de Ven Mies , Borgers Marcel
Published: January 2008

Object

The authors describe an experimental model of closed head injury in rodents that was modified from one developed by Marmarou and colleagues. This modification allows dual control of the dynamic process of impact compared with impulse loading that occurs at the moment of primary brain injury. The principal element in this weight-drop model is an adjustable table that supports the rat at the moment of impact from weights positioned at different heights (accelerations). The aim was to obtain reproducible pathological intracranial pressure (ICPs) while maximally reducing the incidence of mortality and skull fractures.

Methods

Intracranial pressure was investigated in different experimental settings, including two different rat strains and various impact-acceleration conditions and posttrauma survival times. Identical impact-acceleration injuries produced a considerably higher mortality rate in Wistar rats than in Sprague–Dawley rats (50% and 0%, respectively). Gradually increasing severity of impact-acceleration conditions resulted in findings of a significant correlation between the degree of traumatic challenge and increased ICP at 4 hours (p < 0.001, R2 = 0.73). When the impact-acceleration ratio was changed to result in a more severe head injury, the ICP at 4, 24, and 72 hours was significantly elevated in comparison with that seen in sham-injured rats (4 hours: 19.7 ± 2.8 mm Hg, p = 0.004; 24 hours: 21.8 ± 1.1 mm Hg, p = 0.002; 72 hours: 11.9 ± 2.5 mm Hg, p = 0.009). Comparison of the rise in ICP between moderate and severe impact-acceleration injury at 4 and 24 hours revealed a significantly higher value after severe injury (4 hours: p = 0.008; 24 hours: p = 0.004). Continuous recordings showed that ICP mounted very rapidly to peak values, which declined gradually toward a pathological level dependent on the severity of the primary insult. Histological examination after severe trauma revealed evidence of irreversible neuronal necrosis, diffuse axonal injury, petechial bleeding, glial swelling, and perivascular edema.

Conclusions

This modified closed head injury model mimics several clinical features of traumatic injury and produces reliable, predictable, and reproducible ICP elevations with concomitant morphological alterations.
Intracranial hypertension and cerebral perfusion pressure: influence on neurological deterioration and outcome in severe head injury
Authors: Juul Niels , Morris Gabrielle F. , Marshall Sharon B. , _ _ , Marshall Lawrence F.
Published: January 2008

Object

Recently, a renewed emphasis has been placed on managing severe head injury by elevating cerebral perfusion pressure (CPP), which is defined as the mean arterial pressure minus the intracranial pressure (ICP). Some authors have suggested that CPP is more important in influencing outcome than is intracranial hypertension, a hypothesis that this study was designed to investigate.

Methods

The authors examined the relative contribution of these two parameters to outcome in a series of 427 patients prospectively studied in an international, multicenter, randomized, double-blind trial of the N-methyl-D-aspartate antagonist Selfotel. Mortality rates rose from 9.6% in 292 patients who had no clinically defined episodes of neurological deterioration to 56.4% in 117 patients who suffered one or more of these episodes; 18 patients were lost to follow up. Correspondingly, favorable outcome, defined as good or moderate on the Glasgow Outcome Scale at 6 months, fell from 67.8% in patients without neurological deterioration to 29.1% in those with neurological deterioration. In patients who had clinical evidence of neurological deterioration, the relative influence of ICP and CPP on outcome was assessed. The most powerful predictor of neurological worsening was the presence of intracranial hypertension (ICP ≥ 20 mm Hg) either initially or during neurological deterioration. There was no correlation with the CPP as long as the CPP was greater than 60 mm Hg.

Conclusions

Treatment protocols for the management of severe head injury should emphasize the immediate reduction of raised ICP to less than 20 mm Hg if possible. A CPP greater than 60 mm Hg appears to have little influence on the outcome of patients with severe head injury.
Historical movements in transsphenoidal surgery
Authors: Gandhi Chirag D. , Post Kalmon D.
Published: January 2008

Over the past century pituitary surgery has undergone multiple revolutions in surgical technique and technological advancements that have resulted in what is now recognized as modern transsphenoidal surgery. Although the procedure is well established in the current neurosurgical literature, the historical maze that led to its development continues to be of interest because it allows us to appreciate better the unique contributions made by the pioneers of the technique as well as the innovative spirit that continues to fuel neurosurgery. The early events in the history of transsphenoidal surgery have already been well documented. Therefore, the authors summarize the major early transitions along the timeline and then further describe more recent advancements in transsphenoidal surgery such as the surgical microscope, fluoroscopy, endoscopy, intraoperative neuroimaging, frameless image guidance, and radioimmunoassay. The story of these innovations is unique because each was developed as a response to certain needs of the surgeon. An understanding of these more recent contributions coupled with the early history provides a more complete perspective on modern transsphenoidal surgery.
Functional evaluation of arteriovenous malformations
Authors: Bambakidis Nicholas C. , Sunshine Jeffrey L. , Faulhaber Peter F. , Tarr Rober W. , Selman Warren R. , Ratcheson Robert A.
Published: January 2008

Detailed knowledge of the angioarchitecture of arteriovenous malformations (AVMs) is necessary in determining the optimal timing and method of treatment of these challenging lesions. Many techniques are available for studying the functionality of surrounding cortical structures of AVMs. These include the use of positron emission tomography, functional magnetic resonance imaging, magnetoencephalography, and direct provocative testing of cortical function. The use of these methods to determine flow dynamics and tissue perfusion is also reviewed. These techniques are discussed in the present study, and their judicious utilization will enhance the safety of AVM therapy.
Grading and surgical planning for intracranial arteriovenous malformations
Authors: Riina Howard A. , Gobin Y. Pierre
Published: January 2008

The treatment of arteriovenous malformations (AVMs) has evolved over the last 40 years. These complex vascular lesions remain among the most difficult lesions to treat. Successful treatment of AVMs of the brain includes extensive preoperative planning, multimodality treatment options, and modern postoperative surgical care. The advent of new technologies, including interventional neuroradiology and radiosurgery, has expanded the range of malformations that can be treated effectively and has had a significant impact on those individuals who manifest this disease process. The purpose of this paper is to describe the current grading technique used by the authors and to explore the preoperative treatment and planning that leads to successful surgical obliteration of these lesions. Some description of preoperative interventions, including radiosurgery and interventional procedures will be mentioned; however, only in the context of how they impact on the surgical treatment of these lesions. In other articles in this edition of Neurosurgical Focus interventional procedures and radiosurgery as treatment adjuncts and as primary therapies will be discussed in greater detail.
Postoperative radicular neuroma
Authors: Erman Tahsin , Tuna Metin , Göçer A. İskender , İdan Faruk , Akgül Erol , Zorludemir Suzan
Published: January 2008

Lumbar discectomy is the most common surgical procedure performed in neurosurgery clinics. Such a large number of procedures underscore not only the prevalence of conditions such as intervertebral disc herniation, but also the strong belief of surgeons that the operation does provide benefits to patients suffering from sciatica. In spite of this belief, sciatic pain may continue after the surgery. The recurrence of sciatic and/or back pain after primary discectomy is called the “failed back surgery syndrome.”

The rate of the complications involved in standard lumbar discectomy ranges from 5.4 to 14%. One of the complications of the lumbar disc surgery is nerve root injury. The complication rate of this injury ranges from 0.7 to 2.2%. Postoperative radicular neuroma must be considered in differential diagnosis for the patient who has failed back surgery syndrome. In this study the authors evaluate a patient who had undergone surgery for lumbar disc herniation and suffered intractable pain. A traumatic radicular neuroma is demonstrated and the pertinent literature is presented.
Metastatic spinal tumors
Authors: Heary Robert F. , Bono Christopher M.
Published: January 2008

Metastatic spinal tumors are the most common type of malignant lesions of the spine. Prompt diagnosis and identification of the primary malignancy is crucial to overall treatment. Numerous factors affect outcome including the nature of the primary cancer, the number of lesions, the presence of distant nonskeletal metastases, and the presence and/or severity of spinal cord compression. Initial management consists of chemotherapy, external beam radiotherapy, and external orthoses. Surgical intervention must be carefully considered in each case. Patients expected to live longer than 12 weeks should be considered as candidates for surgery. Indications for surgery include intractable pain, spinal cord compression, and the need for stabilization of impending pathological fractures. Whereas various surgical approaches have been advocated, anterior-approach surgery is the most accepted procedure for spinal cord decompression. Posterior approaches have also been used with success, but they require longer-length fusion. To obtain a stable fixation, the placement of instrumentation, in conjunction with judicious use of polymethylmethacrylate augmentation, is crucial. Preoperative embolization should be considered in patients with extremely vascular tumors such as renal cell carcinoma. Vertebroplasty, a newly described procedure in which the metastatic spinal lesions are treated via a percutaneous approach, may be indicated in selected cases of intractable pain caused by non- or minimally fractured vertebrae.
Medical management and adjuvant therapies in spinal metastatic disease
Authors: Schuster James M. , Grady M. Sean
Published: January 2008

Metastatic spinal tumors are an increasingly common and difficult problem encountered by neurosurgeons and orthopedic surgeons. To improve therapies and increase life expectancy for patients with tumors such as those of the breast and prostate, a global, systematic approach is required to maximize the preservation of neurological function, maintenance of spinal stability, and relief of pain, all with the ultimate goal of improved functional capacity and quality of life (QOL). Although radiotherapy and surgery are still the primary therapeutic options, several new adjuvant therapies initially implemented to control pain more effectively have also been shown to reduce overall skeleton-related complications (pathological fractures and hypercalcemia) and may ultimately improve and extend QOL. This more global approach to spinal metastases also includes optimizing each patient's overall medical condition and potential for healing (that is, nutrition), as well as avoiding potential complications associated with metastatic disease (such as deep vein thrombosis), including excessive blood loss in the case of renal metastasis. A thorough knowledge and understanding of these therapeutic adjuvants is required to optimize care and to respond to our increasingly medically knowledgable patient population whose access to prevalent medical information has been increased because of the internet.
Perioperative complications with costotransversectomy and anterior approaches to thoracic and thoracolumbar tumors
Authors: Wiggins Gregory C. , Mirza Sohail , Bellabarba Carlo , West G. Alex , Chapman Jens R. , Shaffrey Christopher I.
Published: January 2008

Object

Anterior decompression and stabilization for thoracic spinal tumors often involves a thoracotomy and can be associated with surgical approach–related complications. An alternative to thoracotomy is surgery via a costotransversectomy exposure.

To delineate the risks of surgery, the authors reviewed their prospective database for patients who had undergone surgery via either of these approaches for thoracic or thoracolumbar tumors. The complications were recorded and graded based on severity and risk of impact on patient outcome.

Methods

Between September 1995 and April 2001, the authors performed 29 costotransversectomies (Group 1) and 18 thoracolumbar or combined (Group 2) approaches as initial operations for thoracic neoplasms. The age, sex, pre-operative motor score, and preoperative Frankel grade did not significantly differ between the groups. In the costotransversectomy group there were greater numbers of metastases, upper thoracic procedures, and affected vertebral levels; additionally, the comorbidity rate based on Charlson score, was higher. The mean Frankel grades at discharge were not significantly different whereas the discharge motor and last follow-up motor scores were better in Group 2. There were 11 Group 1 and seven Group 2 patients who suffered at least one complication. The number or patients with complications, the mean number of complications, and severity of complications did not differ between the groups.

Conclusions

Compared with anterior or combined approaches, the incidence and severity of perioperative complications in the surgical treatment of thoracic and thoracolumbar spinal tumors is similar in patients who undergo costotransversectomy. Costotransversectomy may be the preferred operation in patients with significant medical comorbidity or tumors involving more than one thoracic vertebra.
Stereotactic intensity-modulation radiation therapy for vertebral body and paraspinal tumors
Authors: Bilsky Mark H. , Yenice Kamil , Lovelock Michael , Yamada Josh
Published: January 2008

Therapeutic doses of radiation for paraspinal tumors are often limited by the dose-related tolerance of the spinal cord. Intensity-modulated radiation therapy (IMRT) is an advanced form of three-dimensional conformal radiation therapy that provides improved coverage of tumor volumes while reducing the radiation dose to the spinal cord. Computer-controlled multileaf collimation provides high conformality, which makes it feasible to treat tumors of any shape, even those that are wrapped around the spinal cord. The use of a newly developed, noninvasive body frame, the capability of fusing computerized tomography and magnetic resonance images, and on-line portal films provide precise target immobilization and target identification. In this paper the authors discuss their preliminary experience in six cases in which IMRT was used to treat paraspinal lesions in patients who harbored locally recurrent tumors and/or tumors that previously received the maximum doses of radiation that could be tolerated by the spinal cord.
Pediculotomy as an adjunct to posterior cervical hemilaminectomy, foraminotomy, and discectomy
Authors: Webb K. Michael , Kaptain George , Sheehan Jonas , Jane John A.
Published: January 2008

Currently the posterior approach undertaken to perform cervical hemilaminectomy and foraminotomy provides sufficient exposure to treat the majority of lateral soft-disc herniations or osteophytes causing radiculopathy. Limitations imposed by the surgical field, however, often necessitate excessive retraction of the nerve root and epidural venous plexus, which may potentially exacerbate a preexisting radiculopathy or increase intraoperative blood loss. Partial resection of the inferior pedicle augments exposure and enlarges the neural foramen, thus facilitating decompression while minimizing manipulation of the nerve root and epidural venous plexus.

With the patient in the prone position, partial hemilaminectomy and foraminotomy are performed using a high-speed 3-mm diamond burr with continuous irrigation. The thecal sac and nerve root are exposed, and the overlying fibroareolar layer is coagulated and incised. With the nerve root protected and under direct vision, the superomedial portion of the inferior pedicle is removed. Nerve root decompression is then performed through this augmented exposure.

Partial excision of the pedicle allows for more expeditious removal of the pathological elements causing cervical radiculopathy and requires minimal manipulation of the nerve root and epidural venous plexus. This procedure results in a potential decrease in transient postoperative radiculopathy and minimization of intraoperative blood loss. In addition, the resulting foraminal enlargement enhances the decompression provided by traditional foraminotomy, even if discectomy is not performed.
The Cervical Spine Study Group anterior cervical plate nomenclature
Authors: Haid Regis W. , Foley Kevin T. , Rodts Gerald E. , Barnes Bryan
Published: January 2008

The authors review historical and biomechanical aspects of anterior cervical plate (ACP) systems. They propose a novel classification system for ACPs based on the biomechanical and graft-loading properties of these systems.

A retrospective review of the literature comprising both clinical and laboratory investigations regarding the ACP system was undertaken. Comparison of each system is considered in the context of the biomechanical attributes and graft-loading properties of each type of plate. Salient characteristics reviewed include restriction of screw backout, screw-angle variability, and mobility at the screw–plate interface. A new classification system for ACPs is proposed that primarily considers the ability of the construct to restrict screw backout, as well as the properties of the plate–screw interface—that is, the capacity for rotational or translational movement.

A new classification system is presented that provides unified, biomechanically descriptive nomenclature. Using this nomenclature, the ACP devices currently available and those developed in the future can be uniformly categorized.
Posterior cervical fixation using a new polyaxial screw and rod system: technique and surgical results
Authors: Mummaneni Praveen V. , Haid Regis W. , Traynelis Vincent C. , Sasso Rick C. , Subach Brian R. , Fiore Amory J. , Rodts Gerald E.
Published: January 2008

Object

Standard lateral mass plate and screw systems are of limited use in patients with abnormal cervical anatomy and do not easily allow for extension to either the occipit or the thoracic spine. The objective of this study was to demonstrate the safety, surgical efficacy, and advantages of a new cervical polyaxial screw and rod system for posterior occipitocervicothoracic arthrodesis.

Methods

The authors reviewed a multicenter series of patients who underwent surgery in which they used a new posterior cervical polyaxial screw and rod system. The system was implanted in 32 (20 women and 12 men) adult patients (mean age 56.9 years, range 23–84 years). Twentythree of the patients were treated for spondylostenosis; four for cervical fracture/dislocations; four for kyphosis; and one patient was treated for pseudarthrosis that developed after prior surgery.

The system was successfully implanted in all patients despite the presence of anatomical lateral mass anomalies in the majority of cases. The mean number of levels fused was 3.9 (range one–eight levels). This dynamic system allowed for screw placement into the occiput, C-1 lateral masses, C-2 pars, C3–7 lateral masses, and low cervical as well as upper thoracic pedicles. Selective application of compressive or distractive forces was possible in adjacent segments. Surgery-related complications included one dural tear and one malpositioned screw. There were two cases of wound infection.

Conclusions

Unlike standard lateral mass plate and screw systems, the new cervical polyaxial screw and rod system easily accommodates severe degenerative cervical spondylosis and curvatures. This instrumentation system allows for polyaxial screw placement with subsequent multiplanar rod contouring and offset attachment. The authors have used this system successfully, and without significant complications, to achieve posterior cervical arthrodesis.
Common chemical agent threats
Authors: McCafferty Randall R. , Lennarson Peter J.
Published: January 2008

The events of September 11, 2001, highlight the fact that we live in precarious times. National and global awareness of the resolve and capabilities of terrorists has increased. The possibility that the civilian neurosurgeon may confront a scenario involving the use of chemical warfare agents has heightened. The information reported in this paper serves as a primer on the recognition, decontamination, and treatment of trauma patients exposed to chemical warfare agents.
What neurosurgeons should do to succeed in tomorrow's scientific and socioeconomic environment
Authors: Ausman James I. , Pawl Ronald P.
Published: January 2008

There will be major scientific advances and socioeconomic changes in the 21st century that will influence the development of medicine and neurosurgery. These changes will affect those in academic medical centers and the private practitioners of medicine and neurosurgery. Neurosurgeons' philosophy and practice methods must adapt to these trends. Because of the continuing growth in scientific knowledge and the rapid spread of communications of all types, physicians will best work in groups and teams. These group forces will require the physicians to surrender some independence to gain the power of the integrated knowledge and political and social force of a group. Graduate and postgraduate education programs will also change to adapt to these new realities. Those who understand these new shifts will be the most successful in establishing and conducting practices in academic centers and private practice.
Valuing neurosurgery services: Part II. The interdependence of Current Procedural Terminology and federal Medicare payment policy
Authors: Bean James R.
Published: January 2008

Current Procedural Terminology (CPT) policies for coding of medical procedures and services are adopted by the American Medical Association CPT editorial panel. Since institution of the Medicare Fee Schedule in 1992, the Medicare budget neutrality rule has strongly influenced CPT policies for the coding of additions or modifications. The Centers for Medicare and Medicaid Services Medicare program policies, particularly payment limits, influence code modification strategies and CPT editorial panel processes.
Understanding and applying a resource-based relative value system to your neurosurgical practice
Authors: Przybylski Gregory J.
Published: January 2008

The payment policy for United States physicians was formerly based on determination of customary and prevailing charges from their fee schedules. Rapidly growing health care expenditures in the 1980s led to a fundamental change in payment reimbursement in which the new system was based on the resource costs to the physician for providing health care services. This reform highlights the significant regulatory morass that has come to burden the health care industry. One of the most critical changes in physician reimbursement was caused by the Congressional mandate that led to the development of a resource-based relative value scale (RBRVS) for the creation of the Medicare physician fee schedule. Most physicians, however, have limited familiarity with the RBRVS system, which now serves as the basis for Medicare-related physician reimbursement as well as many third-party payers. A historical review of the development of the RBRVS will serve as the basis for applying the methodology to improve the effectiveness of the neurosurgeon's practice.
Physician ownership of specialty spine hospitals
Authors: Tibbs Robert E. , Pelofsky Stanley , Friedman Eric S. , Blaylock Kevin
Published: January 2008

Patients expect and deserve quality medical care. Physicians, by nature, want what is best for their patients. With the advent of specialty hospitals, physicians can own, run, and control a superior center designed to deliver the highest quality health care. Neurosurgeons who manage their own hospital may set the standards for medical excellence, with patient satisfaction as their primary focus.
Tumors of the skull base in children: review of tumor types and management strategies
Authors: Tsai Eve C. , Santoreneos Stephen , Rutka James T.
Published: January 2008

Although many treatment strategies for skull base tumors in adults have been reported, relatively little has been reported regarding such therapies in the pediatric population. Skull base tumors in children present a therapeutic challenge because of their unique pathological composition, the constraints of the maturing skull and brain, and the small size of the patients. In this review, the authors examine the pediatric skull base lesions that occur in the anterior, middle, and posterior cranial base, focusing on unique pediatric tumors such as encepahalocele, fibrous dysplasia, esthesioneuroblastoma, craniopharyngioma, juvenile nasopharyngeal angiofibroma, cholesteatoma, chordoma, chondrosarcoma, and Ewing sarcoma. They review management strategies that include radio- and chemotherapy, as well as surgical approaches with emphasis on the modifications and complications associated with the procedures as they apply in children. Evidence for the advantages and limitations of radiotherapy, chemotherapy, and surgery as it pertains to the pediatric population will be examined. With a working knowledge of skull base anatomy and special considerations of the developing craniofacial skeleton, neurosurgeons can treat skull base lesions in children with acceptable morbidity and mortality rates. Outcomes in this population may be better than those in adults, in part because of the benign histopathology that frequently affects the pediatric skull base, as well as the plasticity of the maturing nervous system.
Facial paralysis caused by malignant skull base neoplasms
Authors: Marzo Sam J. , Leonetti John P. , Petruzzelli Guy
Published: January 2008

Object

Bell palsy remains the most common cause of facial paralysis. Unfortunately, this term is often erroneously applied to all cases of facial paralysis.

Methods

The authors performed a retrospective review of data obtained in 11 patients who were treated at a university-based referral practice between July 1988 and September 2001 and who presented with acute facial nerve paralysis mimicking Bell palsy. All patients were subsequently found to harbor an occult skull base neoplasm. A delay in diagnosis was demonstrated in all cases. Seven patients died of their disease, and four patients are currently free of disease.

Conclusions

Although Bell palsy remains the most common cause of peripheral facial nerve paralysis, patients in whom neoplasms invade of the facial nerve may present with acute paralysis mimicking Bell palsy that fails to resolve. Delays in diagnosis and treatment in such cases may result in increased rates of mortality and morbidity.
Esthesioneuroblastoma: clinical presentation, radiological, and pathological features, treatment, review of the literature, and the University of Virginia experience
Authors: Oskouian Rod J. , Jane John A. , Dumont Aaron S. , Sheehan Jonas M. , Laurent Jeffrey J. , Levine Paul A.
Published: January 2008

Esthesioneuroblastoma is a rare and malignant upper nasal cavity neoplasm involving the anterior skull base. Treatment includes surgery, radiotherapy, chemotherapy, or a combination. The ideal treatment modality has yet to be determined. Esthesioneuroblastoma often lies in proximity to the optic nerves, optic chiasm, and the orbit. Resection risks damaging these critical structures, and radiotherapeutic techniques, similar to those applied for paranasal sinus tumors, may damage these vital structures and result in late sequelae such as blindness and cortical necrosis.

Management strategies for this neoplasm lack uniformity, and there is no universally accepted staging system. In this paper the authors discuss the clinical presentation, radiological and pathological features, and treatment of this rare, malignant skull base neoplasm, as well as review the literature. They also present their results and treatment regimen, which includes preoperative radio- and chemotherapy or 1) craniofacial resection if the lesion has a significant intrac-erebral component, or 2) frontal sinus resection if little intracranial extension exists.
Operative management of skull base malignancies: choosing the appropriate approach
Authors: Pieper Daniel R. , Larouere Michael , Jackson Ian T.
Published: January 2008

Malignant tumors of the skull base are complex lesions. Identifying the indications and contraindications for resection is essential for the successful treatment of these lesions. This requires an understanding of the pathology, principles of resection, and nonsurgical therapeutic modalities. Choosing the appropriate surgical approach requires an understanding of the tumor and its association with the anatomy of the skull base. Preoperative assessment and preparation of the patient for the postoperative course, including functional and cosmetic deficits, are reviewed in the context of the specific approach. Anatomical variations encountered in the preoperative planning are discussed. A review of reconstructive alternatives is presented that is specific to the approach and anatomical violation. Finally, the use of a multidisciplinary team both in and out of the operating room is recommended, emphasizing a team approach during the resection itself.
Review of neurocysticercosis
Authors: Sotelo Julio , Del Brutto Oscar H.
Published: January 2008

In the neurosurgical services in many developing countries, treatment of neurocysticercosis (NCC) accounts for greater than 10% of brain surgical procedures and approximately 15% of neurological consultations. In these areas brain cysticercosis is the leading cause of hydrocephalus in adults and the first cause of late-onset epilepsy. During the last two decades, successful medical treatment has been established. Additionally, neuroimaging and immunological studies have clearly defined the topography, pathophysiological mechanisms, and biological status of these lesions. Thus, selection of cases for medical or surgical treatment has improved; in a significant number of cases, both interventions are required. New therapies with either albendazole or praziquantel have respectively reduced to 8 days and to 1 day the course of anticysticidal therapy, which now is fast, effective, inexpensive, atoxic, and convenient, particularly in endemic areas where most patients belong to the lower socioeconomic groups. Additionally, the rational use of steroid agents facilitates the treatment of inflammation, a conspicuous accompaniment in cases of NCC. A major effort, however, is still required to eradicate this disease.
Deaths associated with cysticercosis
Authors: Degiorgio Christopher M. , Houston Iceland , Oviedo Sandra , Sorvillo Frank
Published: January 2008

There is significant concern about an increased risk of death in patients with neurocysticercosis who receive anti-helminthic agents. To clarify the risk factors for death associated with cysticercosis, the authors identified all cases of mortality over a 5-year period in patients in whom cysticercosis was diagnosed and who were discharged from a major metropolitan medical center. In addition, they reviewed the literature to delineate risk factors associated with cysticer-cosis-related death, concluding that the risk of death is highest in patients with heavy cyst burdens and those surgically treated for intracranial hypertension. Death is rare in properly selected patients with parenchymal disease in whom the cyst burden is low and intracranial hypertension is absent. The most common causes of death appear to be 1) intracranial hypertension in surgically treated patients and 2) shunt infection.
Imaging features and surgery-related outcomes in intraventricular neurocysticercosis
Authors: Citow Jonathan Stuart , Johnson J. Patrick , McBride Duncan Q. , Ammirati Mario
Published: January 2008

Object

Neurocysticercosis (NCC) is the most common parasitic infection of the central nervous system, and its prevalence is continuing to increase in the United States. The diagnosis of intraventricular NCC (IVNCC) may be difficult, and surgery frequently fails to resolve symptoms. A retrospective review of magnetic resonance (MR) imaging characteristics and surgery-related outcomes may improve management strategies of this disease.

Methods

The authors report the presentations, neuroimaging characteristics, surgical management, and outcomes of 30 patients with IVNCC treated over a 10-year period (mean follow-up period 4 years). Cysts were located in the lateral ventricles (five cases), the third ventricle (five cases), and the fourth ventricle (21 cases). One patient had lesions in both the lateral and fourth ventricles. Presenting symptoms were related to hydrocephalus or mass effect from the lesions.

All patients underwent computerized tomography (CT) and MR imaging of the brain. Treatment consisted of shunt implantation or primary excision of an IVNCC lesion. Outcomes after operations and reoperations were evaluated in light of enhancement characteristics on MR imaging.

Computerized tomography scanning demonstrated IVNCC lesions in 10% of cases, and MR revealed lesions in 100% of cases. In patients in whom gadolinium (Gd) enhancement of IVNCC lesions was demonstrated on MR imaging, the surgery-related failure rate was higher and patients required reoperation, and in those in whom gadolinium enhancement was absent the surgery-related failure rate was lower (64 and 19%, respectively; p < 0.0002).

Conclusions

Magnetic resonance imaging is superior to CT scanning for detecting IVNCC lesions. The absence of pericystic Gd enhancement on MR imaging is an indication for excision of the lesions. If pericystic enhancement is present, shunt surgery should be performed, and craniotomy reserved for treatment of those patients with symptomatic lesions secondary to mass effect. A treatment algorithm based on patient symptoms, cyst location, and MR imaging Gd enhancement characteristics is proposed.
Reduction of spondylolisthesis
Authors: Rengachary Setti S. , Balabhandra Raju
Published: January 2008

In this article the authors discuss the syndrome of isthmic spondylolisthesis occurring at the lumbosacral junction in adults, providing a description of the clinical syndrome, altered biomechanics, and imaging characteristics. The authors pose arguments in favor of reduction and instrument-assisted fusion. Their surgical technique is detailed. They describe transsacral interbody fusion in which fibular allograft and in situ fixation are used, which they consider the second-best alternative technique when attempts at reduction fail.
Stress fracture of the pedicle after extensive decompression and contralateral posterior fusion for lumbar stenosis
Authors: Sheehan Jason P. , Helm Gregory A. , Sheehan Jonas M. , Jane John A.
Published: January 2008

Lumbar spinal stenosis can be effectively treated by performing an extensive ipsilateral spinal decompression, including a partial pediculotomy, and contralateral posterior bone fusion. Infrequently, complications can arise following radical decompression to alleviate symptoms of stenosis, and one such complication is a pedicle fracture. Three reports of pedicle fractures following extensive spinal decompression and contralateral posterior fusion are detailed. This complication is emphasized, and interventions are discussed.

Three patients presented with symptoms attributable to lumbar stenosis; they were initially treated with an ipsilateral decompression, achieved in part, through a partial pediculotomy followed by contralateral autologous bone fusion. Initially, all three patients improved postoperatively; however, they later developed neurological symptoms ipsilateral to the side of spinal decompression. Computerized tomography scanning demonstrated pedicle fractures on the decompressed side. This complication has not yet been reported in association with decompression and fusion for lumbar stenosis.

Two of the patients developed leg pain necessitating reoperation whereas the third experienced only mild transient symptoms. The fractured pedicle was removed in one patient; laminar and spinous process fusion was performed again. Another patient underwent a total laminectomy, removal of the fractured pedicle, and bilateral transverse process fusion. Reoperation yielded satisfactory outcomes. The third patient's symptoms resolved without intervention.

Pedicle fractures are a potential complication of extensive lumbar decompression and contralateral posterior fusion. Loading forces from the facets or transverse processes are possibly the cause of such fractures. Removal of the fractured pedicle, additional decompression, and enhanced bone fusion are recommended when the symptoms warrant surgical intervention.
Spinal arthroplasty
Authors: Traynelis Vincent C.
Published: January 2008

Symptomatic degenerative spinal disease is a serious medical condition that affects many individuals. Modern neuroimaging modalities, the development of new medications, and advances in operative and nonoperative treatments have all contributed to improved outcomes. Unfortunately, there remain a significant number of patients in whom primary therapy either fails or new or recurrent symptoms develop over time. The last decade has witnessed the invention of devices designed to reconstruct the spinal motion segment. These devices can be divided into those that primarily function to replace a nucleus pulposus and those that completely replace the disc complex. In this article the author reviews the background leading to the development of the current group of disc replacements. The design and preliminary clinical results obtained using major lumbar and cervical devices are also reviewed.
Guidelines for the use of discography for the diagnosis of painful degenerative lumbar disc disease
Authors: Resnick Daniel K. , Malone David G. , Ryken Timothy C.
Published: January 2008

Object

Discography has been used as a diagnostic test in the evaluation of patients with recalcitrant low-back pain. Recently, its usefulness has been questioned because of the occurrence of false-positive results as well as the influence of psychological factors on test results. The purpose of this review is to establish the literature support for and against the use of discography.

A search of the English-language literature published between 1966 and 2001 was performed. Papers were selected based on inclusion criteria described in the text, and the quality of information was graded using previously described methods.

Conclusions

The authors propose a set of practice parameters based on the literature. Although the data were not judged adequate for the determination of a treatment standard, parameters for the use of discography are provided at a guideline and option level.
Pathophysiology of lumbar disc degeneration: a review of the literature
Authors: Martin Michael D. , Boxell Christopher M. , Malone David G.
Published: January 2008

Lumbar disc degeneration occurs because of a variety of factors and results in a multitude of conditions. Alterations in the vertebral endplate cause loss of disc nutrition and disc degeneration. Aging, apoptosis, abnormalities in collagen, vascular ingrowth, loads placed on the disc, and abnormal proteoglycan all contribute to disc degeneration. Some forms of disc degeneration lead to loss of height of the motion segment with concomitant changes in biomechanics of the segment. Disc herniation with radiculopathy and chronic discogenic pain are the result of this degenerative process.
Use of a tubular retractor system in microscopic lumbar discectomy: 1 year prospective results in 135 patients
Authors: Palmer Sylvain
Published: January 2008

Object

Application of minimally invasive techniques to lumbar disc surgery has led to the development of the Microscopic Endoscopic Tubular Retractor System (METRx-MD). A prospective evaluation of results and complications was undertaken.

Methods

One hundred thirty-five patients underwent surgery in which the METRx-MD system was used; most procedures were performed on an outpatient basis, and general anesthesia was induced in all cases. All patients were followed prospectively. Outcomes were measured using a visual analog scale (VAS), the Oswestry Disability Index (ODI), and the Short Form–36 (SF-36) questionnaires. Follow-up data were collected by an outside company, which also tabulated the data.

Data were collected in 129 of 135 patients. Improvement was seen on the VAS (Scores 7–2), ODI (Scores 57–16), and SF-36 scales (bodily pain Scores 20–60). Patient satisfaction with results was 94% and with office services 88%. Thirty-six percent of patients returned to work at 0 to 2 weeks, 38% at 3 to 5 weeks, and 25% at 5 to 26 weeks. Hospital charges decreased by $2395 (18%).

The mean operative time was 66 minutes, and the mean blood loss was 22 ml. Complications included one superficial wound infection, one discitis, three durotomies, and three cases of excessive bleeding (> 100 ml). There were five reoperations: four for recurrent disc herniations, (two ipsilateral and two contralateral to the index site) and one for spinal stenosis contralateral to the index site.

Conclusions

Minimally invasive surgery in which the METRx-MD system is used is clinically effective and cost effective. Patient satisfaction was high. A mean per case cost savings of $2395 was realized. Complications rates were comparable with those associated with traditional microdiscectomy procedures.
Alternative strategies for lumbar discectomy: intradiscal electrothermy and nucleoplasty
Authors: Welch William C. , Gerszten Peter C.
Published: January 2008

In recent years the general trend in spinal surgery has been one of reductionism and minimalization. A number of techniques have recently been developed that are applicable in the treatment of lumbar disc herniation and discogenic pain due to degenerative disc disease. The purpose of this manuscript is to examine two newer percutaneous disc treatment techniques, intradiscal electrothermal therapy (IDET) anuloplasty and nucleoplasty. The authors review the appropriate clinical treatment criteria, techniques, and lessons learned after performing these procedures in more than 100 patients.

The IDET involves the percutaneous insertion of a specially designed thermal resistance probe followed by controlled heating of the intervertebral disc. This may result in disc shrinkage and reduction in pain. The nucleoplasty procedure involves the percutaneous removal of disc material by using a low-temperature resister probe to disintegrate and evacuate disc material, followed by thermal treatment of adjacent residual disc material. To date, no study has been published in which investigators examine the outcomes of this procedure for the treatment of radicular leg pain and low-back pain.

Both IDET and nucleoplasty appear to be safe procedures. The IDET procedure may be an alternative to lumbar interbody fusion. Although its long-term role is being defined, this technique appears to provide intermediate-term relief of pain in a population of patients with discogenic low-back pain. Nucleoplasty may provide a percutaneous alternative to microdiscectomy in selected cases.
Outcomes research and lumbar discectomy
Authors: Angevine Peter D. , McCormick Paul C.
Published: January 2008

Lumbar discectomy is generally performed to reduce pain or disability and thereby improve quality of life. Important surgery-related results, therefore, include the patients' perceptions of the effect of surgery on their health and ability to perform daily tasks. Spine surgeons should have an understanding of basic concepts of outcome measurement and be able to select appropriate questionnaires and incorporate them into their clinical practices and research. A brief review of the fundamental principles of outcome research is presented, and the recent lumbar discectomy literature concerning these ideas is summarized. Properly designed, conducted, and reported outcome studies of lumbar discectomy will assist the spine surgeon in selecting appropriate patients for surgery, educating them regarding expected results, and comparing this procedure with novel treatments for lumbar disc disease.
Intraoperative optical intrinsic signal imaging: a clinical tool for functional brain mapping
Authors: Pouratian Nader , Cannestra Andrew F. , Martin Neil A. , Toga Arthur W.
Published: January 2008

Optical imaging of intrinsic signals (OIS) is a well-established neuroimaging modality by which functional cortical activity is mapped by detecting activity-related changes in cortical light reflectance. Light reflectance changes are detected by a charged-coupled device camera that captures images of the exposed cortex both at rest and during activity. Although to date OIS has only been used for research purposes, intraoperative OIS (iOIS) holds promise as a clinical mapping tool. In general, iOIS demonstrates good spatial correlation with electrocortical stimulation mapping (ECSM) and other electrophysiological modalities. Additionally, iOIS offers high spatial resolution (in microns), does not make contact with the surface of the brain, and introduces no potentially harmful compounds. Moreover, mapping is relatively rapid.

The authors review the potential contribution of iOIS to the intraoperative environment. Specifically, they review iOIS methodology, discuss signal origin, compare OIS with other functional mapping modalities, and explain its potential benefits and limitations. They propose that iOIS may, in the future, be used in conjunction with ECSM to improve the resolution and accuracy of intraoperative mapping, decrease total time of intraoperative mapping, and possibly improve neurological outcomes. Additional studies will be required to quantify the sensitivity and specificity of optical maps relative to ECSM before it can be implemented clinically.