bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of radiosurgery for multiple brain metastases
Authors: Cho Kwan H. , Hall Walter A. , Gerbi Bruce J. , Higgins Patrick D.
Published: January 2008

Object

The authors evaluated the role of stereotactic radiosurgery (SRS) in patients with multiple brain metastases by analyzing prognostic factors that predict survival.

Methods

Between March 1991 and January 1999, 83 patients with multiple brain metastases underwent SRS in which they used a 6 mV linear accelerator. The median radiation dose of 15 Gy (range 6–50 Gy) was delivered to the 40 to 90% (median 87%) isodose line encompassing the target. Actuarial overall survival was calculated from the date of SRS by using the Kaplan–Meier method. Univariate comparisons of survival between different groups were performed using a log-rank test. All 83 patients were included in the calculation of overall survival. Actuarial overall survival was 22% at 1 year and 13% at 2 years, and a median survival of 5.4 months (range, 0.3–28.8 months) was demonstrated. Variables that predicted survival were Karnofsky Performance Scale (KPS) score, extracranial disease status, and the number of intracranial metastases. Median survival in patients with a KPS score greater than as compared with less than 70 was 9.1 and 2.7 months, respectively (p = 0.002). Median survival when comparing absence and presence of extracranial disease was 9.9 and 4.1 months, respectively (p = 0.02). Median survival in patients harboring two, three, or four or more lesions was 6.6 months, 5.4 months, and 2.7 months, respectively (p = 0.02). In patients with a KPS score greater than or equal to 70 and with three or fewer lesions, median survival was 7 months or longer. In patients with four or more lesions median survival was 7.4 months for those with no extracranial disease and 2.4 months for those with extracranial disease. Other variables tested (sex, histological tumor type, previous resection, location of metastases, treatment modality, and tumor status) did not influence outcome.

Conclusions

The absence of extracranial disease, a KPS score greater than or equal to 70, and fewer number of metastases were shown to be significant predictors of longer survival. Stereotactic radiosurgery appears to be a reasonable therapeutic option in patients with up to three lesions when their KPS score is greater than or equal to 70, regardless of extracranial disease status. In those with four or more metastases, however, SRS should be limited to those with no extracranial disease.
Decision making for patients with multiple brain metastases: radiosurgery, radiotherapy, or resection?
Authors: Kondziolka Douglas , Patel Atul , Lunsford L. Dade , Flickinger John C.
Published: January 2008

Object

Multiple brain metastases are a common health problem, frequently found in patients with cancer. The prognosis, even after treatment with whole-brain radiation therapy (WBRT), is poor, with an average expected survival time of less than 6 months. Investigators at numerous centers have evaluated the role of stereotactic radiosurgery in retrospective case series of patients harboring solitary or multiple tumors. Tumor resection is used mainly for patients with large tumors that cause acute neurological syndromes. The authors conducted a randomized trial in which they compared radiosurgery combined with WBRT with WBRT alone.

Methods

Twenty-seven patients were randomized (14 to recieve WBRT alone and 13 to receive WBRT combined with radiosurgery). The rate of local failure at 1 year was 100% after WBRT alone but only 8% in patients in whom boost radiosurgery was performed. The median time to local failure was 6 months after WBRT alone (95% confidence interval (CI) 3.5–8.5) in comparison to 36 months (95% CI 15.6–57) after WBRT and radiosurgery (p = 0.0005). The median time to the development of any brain failure was improved in the combined modality group (p = 0.002). Survival was shown to be related to the extent of extracranial disease (p = 0.02).

Conclusions

Combined WBRT and radiosurgery for the treatment of patients with two to four brain metastases significantly improves control of brain disease. Whole-brain radiation therapy alone does not provide lasting and effective care when treating most patients. Surgical resection remains important for patients with large symptomatic tumors and in whom limited extracranial disease has been demonstrated.
Analysis of aqueductal cerebrospinal fluid flow after endoscopic aqueductoplasty by using cine phase-contrast magnetic resonance imaging
Authors: Schroeder Henry W. S. , Schweim Christiane , Schweim Klaus H. , Gaab Michael R.
Published: January 2008

Object

The purpose of this prospective study was to evaluate aqueductal cerebrospinal fluid (CSF) flow after endoscopic aqueductoplasty. In all patients, preoperative magnetic resonance (MR) imaging revealed hydrocephalus caused by aqueductal stenosis and lack of aqueductal CSF flow.

Methods

In 14 healthy volunteers and in eight patients with aqueductal stenosis who had undergone endoscopic aqueductoplasty, aqueductal CSF flow was investigated using cine cardiac-gated phase-contrast MR imaging. For qualitative evaluation of CSF flow, the authors used an in-plane phase-contrast sequence in the midsagittal plane. The MR images were displayed in a closed-loop cine format. Quantitative through-plane measurements were performed in the axial plane perpendicular to the aqueduct. Evaluation revealed no significant difference in aqueductal CSF flow between healthy volunteers and patients with regard to temporal parameters, CSF peak and mean velocities, mean flow, and stroke volume. All restored aqueducts have remained patent 7 to 31 months after surgery.

Conclusions

Aqueductal CSF flow after endoscopic aqueductoplasty is similar to aqueductal CSF flow in healthy volunteers. The data indicate that endoscopic aqueductoplasty seems to restore physiological aqueductal CSF flow.
Distraction osteogenesis for craniosynostosis
Authors: Akizuki Tanetaka , Komuro Yuzo , Ohmori Kitaro
Published: January 2008

Object

The authors describe the use of distraction devices and surgical techniques of distraction osteogenesis for the treatment of patients with craniosynostosis.

Methods

Since 1994, the authors have performed distraction procedures in 23 patients with craniosynostosis in whom osteogenesis was achieved. Thirteen of the 23 patients underwent a complete Le Fort III midface osteotomy and distraction. In 10 patients the distraction osteogenesis involved the cranial bone; six underwent combined forehead and midface distraction (Le Fort IV distraction) in which multiple internal devices were used after performing a Le Fort IV osteotomy.

An external distraction procedure was used to treat the first two cases. Since 1996, the authors have used internal devices developed in their unit.

Distraction was initiated 1 week after the osteotomy at the rate of 0.5 mm per day for the cranium and 1.0 mm per day for the midface. The consolidation phase after distraction was initiated was 2 to 3 months.

No major complications such as intracranial infection or neurological deficits were observed during the course of distraction osteogenesis. The osteogenesis generated at the distraction site was considerably satisfactory; and recurrence of the deformity in the follow-up period was minimal.

Conclusions

Distraction osteogenesis for craniofacial deformity has numerous advantages: 1) bone grafting is unnecessary; 2) the procedure is less invasive, has short operating time, and less blood loss occurs than in conventional craniofacial procedures; 3) no intracranial dead space is created; 4) there is a good amount of blood flow to the bone segment; and 5) soft-tissue expansion occurs. The authors believe that distraction osteogenesis is a versatile and stable option for the treatment of patients with craniosynostosis.
Laminotomy/medial facet approach in the excision of thoracic disc herniation
Authors: Black Perry
Published: January 2008

Object

The author describes a technique of thoracic discectomy that has evolved from the posterolateral transfacet and the transpedicular approaches but that spares the pedicle and most of the facet joint.

Methods

This approach was used to remove a total of 11 discs (T6–12) in seven patients. The follow-up period ranged from 8 months to 3 years. In four patients with axial and/or girdle pain significant improvement was demonstrated. The paraparesis in one patient with myelopathy improved postoperatively; that in another patient improved but recurred 8 months postoperatively. In one patient who experienced preoperative leg weakness, the weakness was slightly increased postoperatively, but this sequela was only transient. There were no other complications, and there were no deaths.

Conclusions

This technique appears safe and effective. It can be adapted to the conventional laminectomy known to spine surgeons and requires no specialized instruments. Further trials appear warranted.
Techniques of intraoperative cerebral blood flow measurement
Authors: Friedman Jonathan A. , Anderson Robert E. , Meyer Fredric B.
Published: January 2008

Understanding the physiological mechanisms of cerebral blood flow (CBF) is of great importance to neurosurgeons engaged in the management of patients with cerebrovascular disease. Over the past 50 years, techniques to measure CBF and mathematical methods to calculate CBF have evolved substantially. For the cerebrovascular surgeon, intra-operative CBF monitoring is an important adjunct in certain intra- and extracranial procedures. The authors review current techniques in use for the intraoperative measurement of CBF.
Tethered cord syndrome and occult spinal dysraphism
Authors: Warder Daryl E.
Published: January 2008

Tethered cord syndrome is a progressive form of neurological deterioration that results from spinal cord tethering by various dysraphic spinal abnormalities. The syndrome, treatments, outcomes, and current controversies are reviewed.
Spinal neurenteric cysts and their relation to more common aspects of occult spinal dysraphism
Authors: Rauzzino Michael J. , Tubbs R. Shane , Alexander Eben , Grabb Paul A. , Oakes W. Jerry
Published: January 2008

Object

Neurenteric cysts are infrequently reported congenital abnormalities believed to be derived from an abnormal connection between the primitive endoderm and ectoderm. The authors report a series of 13 patients treated over a 50-year period.

Methods

Of the 13 patients, seven were female and six were male. Their ages at presentation ranged widely from 5 weeks to 52 years of age. Children presented more commonly with cutaneous stigmata of occult spinal dysraphism (OSD) whereas adults presented primarily with pain. Neurological deficit as a presenting symptom was less common in our series, a finding that reflects the slow growth of these lesions. In all but one patient some form of vertebral anomaly was associated with the cystic lesions, including two patients with Klippel–Feil abnormalities. There was a high incidence of associated forms of OSD including split cord malformation, lipoma, dermal sinus tract, and tethered spinal cord. In previous reports the authors have suggested that neurenteric cysts are more common in the cervical region and in a position ventral to the cord. In the present series these cysts most commonly occurred as intradural, extramedullary masses in the thoracolumbar region, situated dorsal to the spinal cord. The median follow-up period was 7.5 years, and postoperative outcome reflected a patient's preoperative neurological status; in no patient was outcome worsened due to surgery.

Conclusions

Complete excision of the neurenteric cyst remains the treatment of choice, as subtotal excision is associated with recurrence.
Ventral tethering in split cord malformation
Authors: Pang Dachling
Published: January 2008

Object

The author studied the specific issue of ventral tethering in cases of type II split cord malformation (SCM). He also discussed the issue of ventral tethering in patients with type I SCM in whom a bony septum and dural sleeve have been resected.

Methods

Eleven (21%) of 52 patients with type II SCM were found to have a ventral fibrous septum tethering the hemicords to the ventral dura. Four categories of ventral septa were noted: 1) pure ventral intradural septa (three patients); 2) complete dorsoventral intradural septa (three patients); 3) dorsoventral septa continuous with a dermal sinus tract (two patients); and 4) ventral or complete septa continuous with ventral intestinal bands causing intestinal malrotation or diverticulum (three patients).

Excluding one autopsy case, all 10 patients had symptoms or progressive neurological syndromes at diagnosis. Magnetic resonance imaging was completely ineffective, and computerized tomography (CT) myelography was only partially effective in detecting ventral tethering in 50% of cases. The only other positive predictor of ventral tethering is the association of dermal sinus tract and intestinal malformations. Combining this predictor with CT myelography, only 60% of the cases of ventral tethering could be suspected before surgery.

Conclusions

The author recommends examining all patients with type II SCM, and at surgery the ventral surface of the split length and reunion site should be thoroughly inspected to reveal a ventral band.
Retropleural thoracotomy
Authors: Angevine Peter D. , McCormick Paul C.
Published: January 2008

Herniated thoracic discs, unlike their lumbar counterparts, are difficult to read and safely resect using traditional posterior approaches. Historically, the use of a laminectomy for thoracic disc resection has yielded poor clinical outcomes. Posterolateral and anterolateral approaches have become the standard surgical means of treating these lesions. The traditional anterolateral approach, the transpleural thoracotomy, is an extensive procedure that requires direct retraction of the lung, a deep surgical field, and postoperative closed-chest drainage. An alternative to this anterior approach, the retropleural thoracotomy, is described here. This approach provides the shortest direct route to the thoracic spine and leaves the pleura intact. A smaller incision and less retraction than traditional approaches may reduce postoperative pain and pulmonary-related complications. The retropleural thoracotomy is a valuable technique for the neurosurgeon treating thoracic disc disease.
Intraoperative magnetic resonance imaging–augmented transoral resection of axial disease
Authors: Kaibara Taro , Hurlbert R. John , Sutherland Garnette R.
Published: January 2008

Object

Because transoral decompression of the cervicomedullary junction is compromised by a narrow surgical corridor, the adequacy of decompression/resection may be difficult to determine. This is problematic as spinal hardware may obscure postoperative radiological assessment, or the patient may require reoperation. The authors report three patients in whom high-field intraoperative magnetic resonance (MR) images were acquired at various stages during the transoral resection of C-2 lesions causing craniocervical junction compression.

Methods

In all three patients the lesions involved the cervicomedullary junction: one case each of plasmacytoma and metastatic breast carcinoma involving the odontoid process and C-2 vertebral body, and one case of basilar invagination with a Chiari type I malformation. All three patients presented with progressive myelopathy. Surgery-planning MR imaging studies, performed after the induction of anesthesia, demonstrated the lesion and its relationship to the planned surgical corridor. Transoral exposure was achieved through placement of a Crockard retractor system. In one case the soft palate was divided. Interdissection MR imaging revealed that adequate decompression had been achieved in all cases. In the two patients with carcinoma, posterior instrumentation was placed to achieve spinal stabilization. Planned suboccipital decompression and fixation was averted in the third case because MR imaging demonstrated that excellent decompression had been achieved.

Conclusions

Intraoperatively acquired MR images were instrumental in determining the adequacy of surgical decompression. In one patient the MR images changed the planned surgical procedure. Importantly, the acquisition of intraoperative MR images did not adversely affect operative time or neurosurgical techniques, including the instrumentation procedure.
A reappraisal of surgery for orbital tumors. Part I: extraorbital approaches
Authors: Bejjani Ghassan K. , Cockerham Kimberley P. , Kennerdell John S. , Maroon Joseph C.
Published: January 2008

Orbital lesions are variable in nature and location. Their management can be challenging, and surgical intervention is often needed. Although a significant percentage of these tumors are treated by the ophthalmologist alone, collaboration with a neurosurgeon is often required, especially for tumors that are located deep within the orbit, are large, or have an intracranial extension. Technical advances and modifications in surgical technique have decreased surgery-related morbidity and increased its success. The authors describe their rationale in the choice of a surgical approach, the surgical techniques for extraorbital approaches, and the new surgical adjuvants.
A brief history of aneurysm clips
Authors: Louw Deon F. , Asfora Wilson T. , Sutherland Garnette R.
Published: January 2008

In this communication the authors outline the development of aneurysm clips from those originally used by Walter Dandy to those currently in use. The history is rich in contributions from neurosurgical pioneers and innovators. As a result, the modern neurosurgeon has a wide selection of biocompatible aneurysm clips with known closing pressure, of variable sizes and shapes, and a selection of clip applicators that do not obstruct the surgical field.
Biomechanics of thoracic discectomy
Authors: Wakefield Andrew E. , Steinmetz Michael P. , Benzel Edward C.
Published: January 2008

The thoracic spine is a structurally unique region that renders it uniquely suceptible to thoracic disc herniation. Surgical management strategies are complicated, in part, by the regional anatomical and biomechanical nuances. Surgical approaches include posterior, posterolateral, and anterior routes. Each isassociated with specific indications and contraindications. The biomechanical principles and safe anatomical trajectories must be considered in the surgical decision-making process. These issues are discussed in the pages that follow.
Dose response to cerebrospinal fluid drainage on cerebral perfusion in traumatic brain–injured adults
Authors: Kerr Mary E. , Weber Barbara B. , Sereika Susan M. , Wilberger Jack , Marion Donald W.
Published: January 2008

Object

Intracranial hypertension remains a common complication of traumatic brain injury (TBI). Ventriculostomy drainage is a recommended therapy to decrease intracranial pressure (ICP), but little empirical evidence exists to guide treatment. The authors conducted a study to examine systematically the effect of cerebral spinal fluid (CSF) drainage on ICP and indices of cerebral perfusion.

Methods

Intracranial pressure, cerebral perfusion pressure (CPP), cerebral blood flow velocity (CBFV), and near-infrared spectroscopy–determined regional cerebral oxygenation (rSO2) were measured in 58 patients (with Glasgow Coma Scale scores ≤ 8) before, during, and after ventriculostomy drainage. Three randomly ordered CSF drainage protocols varied in the volume of CSF removed (1 ml, 2 ml, and 3 ml). Physiological variables were time averaged in 1-minute blocks from baseline to 10 minutes after cessation of ventricular drainage.

There was a significant dose–time interaction for ICP with the three-extraction volume protocol, with incremental decreases in ICP (F [20, 1055] = 6.10; p = 0.0001). There was a significant difference in the CPP depending on the amount of CSF removed (F [2, 1787] = 3.22; p = 0.040) and across time (F [10, 9.58] = 11.9; p = 0.0003) without a significant dose–time interaction. A 3-ml withdrawal of CSF resulted in a 10.1% decrease in ICP and a 2.2% increase in CPP, which were sustained for 10 minutes. There was no significant dose, time or dose–time interaction with CBFV or rSO2.

Conclusions

Cerebrospinal fluid drainage (3 ml) significantly reduced ICP and increased CPP for at least 10 minutes. Analysis of these findings supports the use of ventriculostomy drainage as a means of at least temporarily reducing elevated ICP in patients with TBI.
Epidemiology and natural history of arteriovenous malformations
Authors: Stapf Christian , Mohr Jay P. , Pile-Spellman John , Solomon Robert A. , Sacco Ralph L. , Connolly E. Sander
Published: January 2008

The epidemiology and natural history of cerebral arteriovenous malformations (AVMs) remains incompletely elucidated. Several factors are responsible. With regard to the incidence and prevalence of AVMs, the results of prior studies have suffered because of the retrospective design, the use of nonspecific ICD-9 codes, and a focus on small genetically isolated populations. Recent data from the New York Islands AVM Hemorrhage Study, an ongoing, prospective, population-based survey determining the incidence of AVM-related hemorrhage and the associated rates of morbidity and mortality in a zip code–defined population of 10 million people, suggests that the AVM detection rate is 1.21/100,000 person-years (95% confidence interval [CI] 1.02–1.42) and the incidence of AVM-hemorrhage is 0.42/100,000 person-years (95% CI 0.32–0.55). Contemporaneous data from the Northern Manhattan Stroke Study, a prospective, longitudinal population-based study of nearly 150,000 patients in which the focus is to define the incidence of stroke, suggest the crude incidence for first-ever AVM-related hemorrhage to be 0.55/100,000 person-years (95% CI 0.11–1.61). Efforts are ongoing to study the natural history of both ruptured and unruptured AVMs in these datasets to examine the relevance of prior studies of patients selected for conservative follow up in Finland. In addition, data are being gathered to determine whether risk factors for future hemorrhage, which have previously been established in small case series, are valid when applied to whole populations. Together, these data should help inform therapeutic decisionmaking.
Preoperative silk suture embolization of cerebral and dural arteriovenous malformations
Authors: Dehdashti Amir R. , Muster Michel , Reverdin Alain , De Tribolet Nicolas , Ruefenacht Daniel A.
Published: January 2008

Object

The aim of this study was to evaluate the use of silk sutures as a medical implant when applied for the embolization of cerebral and dural arteriovenous malformations (AVMs). The facility of surgery and the clinical significance of complications related to preoperative silk suture embolization were evaluated immediately after surgery and at long-term follow up.

Methods

Thirty-four patients harboring 29 cerebral and five dural AVMs underwent embolization in which silk alone or in association with other agents was used. Medical and radiological records obtained in these 34 patients were reviewed retrospectively. The cerebral AVMs were classified according to the Spetzler–Martin grading system and the dural AVMs to the Djindjian grading system. The facility of the resection and the adverse outcomes, including new neurological deficits, hemorrhage, and fever, as well as histopathological evidence of vessel inflammatory changes, were determined in each case.

In all 23 surgical cases, the AVM could be easily manipulated and excised. New temporary neurological deficits occurred in three patients. A high Spetzler–Martin grade was not associated with a higher incidence of new neurological deficits. One delayed-onset hemorrhage was detected after embolization. Fever was present in 24% of the patients. No sign of significant vasculitis or perivascular inflammation was found on radiological or histopathological examination.

Conclusions

Silk sutures are safe embolic agents especially for proximal occlusion of AVM feeding vessels. New permanent neurological deficits were not encountered in this series. Fever was considered to be a minor, temporary side effect of silk suture embolization.
Evaluation and treatment of spinal metastases: an overview
Authors: Jacobs W. Bradley , Perrin Richard G.
Published: January 2008

Metastases to the spine are a common and somber manifestation of systemic neoplasia. The incidence of spinal metastases continues to increase, likely a result of increasing survival times for patients with cancer. Historically, surgery for spinal metastases has consisted of simple decompressive laminectomy. Results obtained in retrospective case series, however, have shown that this treatment provides little benefit to the patient. With the advent of better patient-related selection practices, in conjunction with new surgical techniques and improved postoperative care, the ability of surgical therapy to play an important and beneficial role in the multidisciplinary care of cancer patients with spinal disease has improved significantly. Controversy remains, however, with respect to the relative merits of surgery, radiotherapy, chemotherapy, or a combination of these treatments.

In this topic review, the literature on spinal column and spinal cord metastases is collated to provide a description of the presentation, investigations, indications for surgical therapy, and the role of adjuvant cancer therapies for patients with spinal metastases. In addition, the authors discuss the different surgical strategies available in the armamentarium of the neurosurgeon treating patients with spinal metastasis.
Image-guided spinal navigation: application to spinal metastases
Authors: Kalfas Iain H.
Published: January 2008

Image-guided spinal navigation is an adjuvant surgical technology that has evolved over the past decade. It has been used as a replacement for conventional intraoperative imaging techniques to improve the spine surgeon's spatial orientation to nonvisualized anatomy. The author will review the principles of image-guided technology in spinal surgery and focus on its application to the management of spinal metastatic disease.
Role of corpectomy in cervical spondylosis
Authors: Kalfas Iain H.
Published: January 2008

The management of cervical spondylosis has evolved over the past several decades. Surgical decompressive and stabilization techniques have become more widely accepted for use in patients with intractable pain or neurological deficits. Advances in neuroimaging, surgical technique, and surgery-related technology including the operating microscope and anterior fixation devices have all contributed to the expanding role of surgery for the treatment of this condition. In this paper the author will focus on the role of corpectomy as a surgical option for managing cervical spondylosis.
Camptocormia treated with bilateral pallidal stimulation
Authors: Nandi Dipankar , Parkin Simon , Scott Richard , Winter Jonathan L. , Joint Carole , Gregory Ralph , Stein John , Aziz Tipu Z.
Published: January 2008

The authors report the neurological, neurophysiological, and neuropsychological effects of using chronic bilateral pallidal high-frequency deep brain stimulation (DBS) in a case of disabling camptocormia.

Deep brain stimulation electrodes were implanted stereotactically to target the globus pallidus internus (GPi) bilaterally. Local field potentials (FPs) were recorded using the DBS electrodes and concurrent abdominal flexor elec-tromyography (EMG) potentials during camptocormic episodes. Videotaped assessments of the movement disorder and neuropsychological evaluation before implantation and at 6 months after initiation of pallidal stimulation were recorded.

There was significant functional improvement following chronic pallidal stimulation, and some improvement was noted in neuropsychological scores. The GPi FPs showed temporal correlation with EMG-recorded rectus abdominis potentials. There were no treatment-related adverse effects.

The authors have found that chronic pallidal stimulation was safe and offered functional benefit in this severely disabling condition. The physiological studies may help further the understanding of the pathophysiology of this rare entity.
Triage for the neurosurgeon
Authors: Wiseman Diana Barrett , Ellenbogen Richard , Shaffrey Christopher I.
Published: January 2008

Triage for the neurosurgeon is a misnomer. The neurosurgeon's role within a mass-casualty situation is one of a subspecialist surgeon instead of a triage officer. Unfortunately because of the events of September 11, 2001, civilian neurosurgeons and other medical specialists have been questioning their role within a mass-casualty situation or, worse, a situation created by biological, chemical, or nuclear weapons. There is no single triage system used exclusively within the United States, and different systems have differing sensitivities, specificities, and labeling methods. The purpose of this article is to discuss varying aspects of triage for both military personnel and civilians and suggest how the neurosurgeon may help shape this process within his or her community. Furthermore, the effects of biological, chemical, and nuclear weapons will be discussed in relation to the triage system.
Weapons of mass destruction and the role of the neurosurgeon
Authors: Moores Leon E.
Published: January 2008

The desire to assist in a crisis should be tempered by a serious assessment of the technical preparation one has undertaken. Additionally, in the same way that a needs assessment is undertaken before prescribing a course of treatment, one should evaluate the actual staffing requirements of the situation. Many physician volunteers were turned away after the World Trade Center attacks because the overwhelming response of available medical personnel quickly exceeded the requirement. Finally, the duration and intensity of preparation should be based on a realistic evaluation of the likelihood of an event occurring that would necessitate use of the training. Before jumping into action in a situation in which weapons of mass destruction have been used, several issues must be addressed. Prior to the crisis, all professionals, neurosurgeons included, should ask how they can prepare themselves and their communities. During the crisis, neurosurgeons should evaluate their roles based on specialized triage training and experience, personal and equipment decontamination training, and the importance of neurosurgical skills. Finally, one should continually ask if there is anything he/she should be doing during the crisis in addition to performing neurosurgical tasks.
Valuing neurosurgery services: Part I. The historical development and interrelationships of Current Procedural Terminology and the Medicare Fee Schedule
Authors: Bean James R.
Published: January 2008

Current Procedural Terminology (CPT) standardizes medical procedure coding for billing and reimbursement. Since adoption of CPT coding as the basis for the Medicare Fee Schedule (MFS) in 1992, CPT coding policies and policy changes have been influenced not only by medical necessity and customary practice, but also increasingly by Medicare payment policies. The MFS created regulatory price control in the United States medical market based on widespread adoption of modified MFS by private payers and benchmark MFS fees governed by federal budget limitations and set annually by government agency (Centers for Medicare and Medicaid Services).
Physician reimbursement under Medicare
Authors: Scarrow Alan M.
Published: January 2008

Payment for physician services in the United States is directly tied to the payment system implemented in the Medicare system. The use of a code to categorize medical and surgical services, as well as a relative value system to assess physician services and reimburse them accordingly, is now well established. In light of this, it is important for physicians to possess knowledge of how this coding and reimbursement system was established, how it is updated, what means are available to modify it, and how it is used in practice. The author addresses these issues, offering a primer for the neurosurgeon on the Medicare system as it relates to physician payment.
Lateral skull base malignancies
Authors: McGrew Benjamin M. , Jackson C. Gary , Redtfeldt Raquel A.
Published: January 2008

Object

Historically poor outcomes have been characteristic in patients with lateral skull base malignancies. As advances in skull base surgical techniques have been made, complete resection has increasingly been achieved. This has resulted in improved survival rates and local tumor control.

Methods

The authors performed a retrospective review of 95 patients treated for lateral skull base malignancies. The mean age of the patients was 49.4 years. There were 44 females and 51 males. The mean follow-up period was 50 months. Resection was performed in all patients, and postoperative radiotherapy was undertaken in 54% of the cases. Local disease control was maintained in 73% of the patients. Tumor involvement of the facial nerve and intracranial tumor extension did not jeopardize the rate of local control.

Conclusions

Despite the fact that technical advances in skull base surgery have resulted in a higher incidence of complete tumor resection and improved survival rates, a respect for the poor prognosis historically associated with lateral skull base malignancies should be maintained and treatment should be appropriately aggressive.
Spinal cord cysticercosis: neurosurgical aspects
Authors: Colli Benedito Oscar , Valença Marcelo Moraes , Carlotti Carlos Gilberto , Machado Hélio Rubens , Assirati João Alberto
Published: January 2008

Object

The authors report their experience in the treatment of 12 symptomatic patients with intradural spinal neurocysticercosis.

Methods

The mean age of the 12 patients was 33 years. There were eight female and four male patients. Cysticercosis was present in association with hydrocephalus in nine cases. In nine of 12 patients the spinal lesion was confined to the thoracic or lumbar spinal cord, and in three the cysticerci occupied the cervical region. In all patients with hydrocephalus nerve root symptoms developed seven to 48 months later (mean 27.6 ± 15.5 months). In one patient hydrocephalus was absent, but he presented with cysticercal meningitis 24 months before spinal cord compression developed. Presenting symptoms suggesting spinal cysticercosis included muscular weakness (67%), pain (67%), and sphincter disturbance (25%). Neurological examination demonstrated a motor deficit in nine patients, sensory deficit in four, and radicular pain in three. The prognosis was worse in patients with moderate-to-severe arachnoiditis and spinal cord compression compared with those with isolated nerve roots involvement in whom outcome was favorable. Ten patients underwent laminectomy, after which neurological status improved in 44%, remained unchanged in 33%, or worsened in 22.2%.

Conclusions

The authors discuss their findings in these cases. Additionally they briefly review the literature, patho-physiology, and therapeutic and/or surgical strategies involved in this disease.
Leiomyosarcomatous transformation of unknown pediatric primary brainstem lesion following radiotherapy
Authors: Yeh David John , Hessler Richard B. , Lee Mark R.
Published: January 2008

Primary leiomyosarcoma of the central nervous system is rare and has been described both de novo and following temporally remote radiotherapy for a different unrelated malignancy. The authors report the case of a 42-year-old man in whom 60Co radiation treatment had been performed for an unknown primary mass in the brainstem 25 years previously. He presented with progressive neurological deterioration after undergoing many years of conservative therapy. A stereotactic biopsy sampling procedure was performed, and examination of the left cerebral pedunculopontine lesion revealed a spindle cell neoplasm. Histopathological and immunohistochemical examination of the tumor obtained from definitive resection suggested leiomyosarcomatous transformation of ganglioglioma.
Isthmic spondylolisthesis
Authors: Ganju Aruna
Published: January 2008

Isthmic spondylolisthesis, which is demonstrated in 4 to 8% of the general population, is one of the most common types of spondylolisthesis. The three subtypes of this condition all manifest some variation of a pars interarticularis defect as a result of recurrent injury to that structure. A multifactorial origin is postulated for this disease; mechanical, hereditary, and hormonal factors are believed to play a role. Presenting signs and symptoms may include those referable to neurological compromise or those related to the spinal deformity. The majority of patients with spondylolysis and spondylolisthesis respond to conservative, nonoperative treatment. Pain, neurological compromise, and cosmetic defects unresponsive to traditional therapies may require surgical intervention. Surgical options include any combination of the following: neural decompression, bone fusion, instrument-assisted fusion, and reduction. In this paper, the natural history and treatment options are presented, and the supporting literature is reviewed.
Circumferential fusion for spondylolisthesis in the lumbar spine
Authors: Heary Robert F. , Bono Christopher M.
Published: January 2008

There are many options for the surgical treatment of lumbar spondylolisthesis, including anterior and posterior techniques. Among the most versatile is a 360° fusion. In consideration of the added risk of morbidity of two procedures, circumferential fusion leads to the highest fusion rates. This is particularly useful for patients at high risk for pseudarthrosis, such as patients with diabetes, posttransplant recipients, and those in whom fusion procedures have failed. Likewise, a 360° fusion may also be useful in achieving fusion in biomechanically disadvantageous situations, such as at the L5–S1 level or with high-grade subluxation. The options for 360° fusion are many and are determined, among other factors, by surgical pathology and surgeon preference. Standard open techniques are still considered the gold standard, although newer less invasive methods of circumferential fusion are being used more frequently. The operating surgeon must have a thorough knowledge of all available maneuvers for critical and effective decision making.
Bilateral decompressive surgery in lumbar spinal stenosis associated with spondylolisthesis: unilateral approach and use of a microscope and tubular retractor system
Authors: Palmer Sylvain , Turner Robert , Palmer Rosemary
Published: January 2008

Object

The objective of this study was to assess the feasibility and efficacy of treating spondylolisthesis-related spinal stenosis via unilateral approach bilateral decompression in which METRx-MD instrumentation is placed.

Methods

Eight consecutive patients with spinal stenosis underwent bilateral decompressions via a unilateral approach in which METRx-MD instrumentation was placed. The procedures were performed on an outpatient basis after induction of general anesthesia. The patients underwent preoperative and 3-month postoperative plain radiography in which flexion–extension x-ray films were obtained. Preoperative and postoperative magnetic resonance imaging was also performed. All radiographs and neuroimages were read by a single radiologist blinded to the clinical results.

Eight vertebral levels in the eight patients were sugically decompressed (in one patient an additional level of non-spondylolisthesis-related stenosis was decompressed). The mean operative time was 92 minutes and the mean blood loss was 33 ml/level. Preoperatively stenosis was severe in five patients, moderate/severe in two, and moderate in one; postoperatively stenosis was absent in five, mild in two, and mild/moderate in one. Motion was detected on flexion–extension radiographs in three patients, but on early (3-month) postoperative radiographs there was no evidence of progression.

Conclusions

By following the authors' procedure, minimally invasive bilateral decompression of acquired spinal stenosis associated with spondylolisthesis can be successfully performed on an outpatient basis, with reasonable operative times, minimal blood loss, and acceptable morbidity.
Indications for and benefits of lumbar facet joint block: analysis of 230 consecutive patients
Authors: Bani Alan , Spetzger Uwe , Gilsbach Joachim M.
Published: January 2008

Object

The authors evaluated the effectiveness of using a facet joint block with local anesthetic agents and or steroid medication for the treatment of low-back pain in a medium-sized series of patients.

Methods

Over a period of 4 years, the authors performed 715 facet joint injections in 230 patients with variable-length histories of low-back pain. The main parameter for the success or failure of this treatment was the relief of the pain. For the first injection—mainly a diagnostic procedure—the authors used a local anesthetic (1 ml bupivacaine 1%). In cases of good response, betamethasone was injected in a second session to achieve a longer-lasting effect.

Long-lasting relief of the low-back pain and/or leg pain was reported by 43 patients (18.7%) during a mean follow-up period of 10 months. Thirty-five patients (15.2%) noticed a general improvement in their pain. Twenty-seven patients (11.7%) reported relief of low-back pain but not leg pain. Nine patients (3.9%) suffered no back pain but still leg pain. One hundred sixteen patients (50.4%), however, experienced no improvement of pain at all. In two cases the procedure had to be interrupted because of severe pain. There were no cases of infection or hematoma.

Conclusions

Lumbar facet joint block is a minimally invasive procedure to differentiate between facet joint pain and other causes of lower-back pain. The procedure seems to be useful for distinguishing between facet joint pain from postoperative pain due to inappropriate neural decompression after lumbar surgery. It can be also recommended as a possible midterm intervention for chronic low-back pain.
Ossification of the cervical posterior longitudinal ligament: a review
Authors: Epstein Nancy
Published: January 2008

Ossification of the cervical posterior longitudinal ligament (OPLL) represents a continuum beginning with hypertrophy of the posterior longitudinal ligament (PLL) followed by progressive coalescence of centers of chondrification and ossification. Early OPLL mimicking disc disease appears opposite multiple disc spaces associated with significant retrovertebral extension, helping to differentiate it from spondylosis. On computerized tomography examinations, the single- and double-layer signs indicate possible dural penetration with the increased potential for an intraoperative cerebrospinal fluid fistula during dissection. Direct ventral resection of OPLL in patients younger than 65 years of age is optimal and includes single- or multilevel anterior corpectomy with fusion, the latter accompanied by posterior fusion. For patients older than the age of 65 years, with a well-preserved cervical lordosis, laminectomy with or without fusion and/or laminoplasty may suffice in providing indirect dorsal decompression. Patients undergoing circumferential procedures with halo devices are managed with a specific anesthetic protocol, including awake intubation and positioning with intraoperative monitoring of somatosensory evoked potentials, electromyography, and the option of undergoing motor evoked potential monitoring. Intubation is maintained during the 1st postoperative night. When circumferential procedures are performed intubation is always maintained during the 1st postoperative night, and fiberoptic postoperative extubation is electively performed by specifically trained anesthesiologists when deemed appropriate. Patients exhibiting three or more major risk factors are considered candidates for delayed extubation and rarely, tracheostomy. Repeated anterior surgery, operations lasting more than 10 hours, involving four or more levels (including C-2), obesity, asthma, and blood transfusions of more than 4 U (1000–1200 ml) are all considered major risk factors.
Effects of nerve root retraction in lumbar discectomy
Authors: Feltes Carlos , Fountas Kostas , Davydov Rostislav , Dimopoulos Vassilios , Robinson Joe Sam
Published: January 2008

The authors studied whether the amount of retraction pressure applied to a compromised nerve root during lumbar discectomy has an impact on intra- or postoperative outcome.

Methods

The authors conducted a prospective analysis of 20 patients. There were 12 men and 12 women whose mean age (± standard deviation [SD]) was 42.25 years ± 15 years (range 21–65 years). During intraoperative electromyography (EMG) monitoring, measurements were obtained during routine retraction of the affected nerve root by using a specially designed and constructed nerve root retractor connected to a reconfigured personal computer for this specific purpose. Follow-up results were assessed in the immediate postoperative period and at up to 1 year. The maximum measured force applied during random periods of time was 9.85 N/second (mean 6.95 ± N/second [± SD]). The mean retraction time was 39.5 ± 21 (SD). No intraoperative EMG-detected irritation was noted during or after routine retraction. In four of 20 patients, sensory changes occurred at the ipsilateral nerve root level, which resolved at the time of discharge.

Conclusions

The authors found that routine nerve root retraction does not cause nerve root irritation, as demonstrated by EMG monitoring, nor was patient outcome affected in this series.
Growth factor gene therapy for Alzheimer disease
Authors: Tuszynski Mark H. , Sang U Hoi , Alksne John , Bakay Roy A. , Pay Mary Margaret , Merrill David , Thal Leon J.
Published: January 2008

The capacity to prevent neuronal degeneration and death during the course of progressive neurological disorders such as Alzheimer disease (AD) would represent a significant advance in therapy. Nervous system growth factors are families of naturally produced proteins that, in animal models, exhibit extensive potency in preventing neuronal death due to a variety of causes, reversing age-related atrophy of neurons, and ameliorating functional deficits. The main challenge in translating growth factor therapy to the clinic has been delivery of growth factors to the brain in sufficient concentrations to influence neuronal function. One means of achieving growth factor delivery to the central nervous system in a highly targeted, effective manner may be gene therapy. In this article the authors summarize the development and implementation of nerve growth factor gene delivery as a potential means of reducing cell loss in AD.