bluuebunny/crossref_metadata_2025 huggingface dataset:
Transcallosal approach for tumors of the lateral and third ventricles
Authors: Kasowski Hahnah , Piepmeier Joseph M.
Published: January 2008

Tumors that arise within the ventricles present a unique surgical challenge. Because of their deep location, relatively large size, and their association with hydrocephalus, surgical planning requires a careful assessment of the optimal method to access the lesion and to provide adequate exposure for tumor resection. The transcallosal approach to the lateral ventricles often is the best procedure by which to achieve these goals.

Partial sectioning of the corpus callosum does not cause significant neurological deficits; however, if the surgery induces additional brain injury, the neurological deficits can be more severe in the presence of a callosotomy. Knowledge of the techniques of transcallosal surgery and careful preoperative planning can reduce the risk of permanent neurological impairment; these range from protection of the cortical veins that drain into the superior sagittal sinus to brain relaxation and ventricular drainage, as well as proper identification of anatomical landmarks within the ventricle. The transcallosal approach can offer a relatively easy access to the lateral and third ventricles, and with proper planning it can reduce the morbidity associated with resection of lesions within these compartments.
Choroid plexus cyst and chordoid glioma
Authors: Hanbali Fadi , Fuller Gregory N. , Leeds Norman E. , Sawaya Raymond
Published: January 2008

Several types of mass lesions may occur in the third and lateral ventricles. Typically they arise from the lining of the ventricular cavity or from contiguous structures, by extension into the ventricle. The authors describe two patients, each of whom presented with a different rare lesion of the ventricular system. The first was a 53-year-old woman with a history of hypertension who sustained a blunt traumatic injury to the occipital region and subsequently developed a progressively worsening right-sided headache. Radiological examinations over the next 2 years revealed an enlarged right lateral ventricle and, ultimately, a choroid plexus cyst in its anterior and middle third, near the foramen of Monro, which is a rare location for these lesions. The cyst was removed en bloc, and follow-up examinations showed a significant improvement in her headache and a minimal differences in size between right and left ventricles. The authors also describe a 57-year-old man with hypertension, diabetes mellitus, and an old mycardial infarct, who presented to an outside institution with a progressively worsening headache, generalized malaise, and loss of olfactory sensation. Diagnostic imaging revealed a 1.5-cm oval lesion centered in the lamina terminalis region, an open craniotomy was performed, and evaluation of a biopsy sample demonstrated the mass to be a chordoid glioma of the third ventricle, a recently described glioma subtype. Two days after surgery, he suffered a left parietal stroke and an anterior mycardial infarction. After convalescing, he presented to The University of Texas M. D. Anderson Cancer Center for radiotherapy and follow up; 7 months later he was readmitted complaining of headache, short-term memory loss, and worsening confusion and disorientation. Neuroimaging revealed progression of the tumor (now 2 cm in diameter), which was removed by gross-total resection. His headache resolved immediately, and 2 months later his only complaint was of episodes of confusion. Three weeks later he died of a massive myocardial infarction. These two patients represent the sixth case of an adult with a choroid plexus cyst in the anterior lateral ventricle and the 19th case of an adult with a chordoid glioma of the third ventricle, respectively.
Surgical treatment of Chiari I malformation: indications and approaches
Authors: Alden Tord D. , Ojemann Jeffrey G. , Park T. S.
Published: January 2008

Chiari I malformation is a well-described entity characterized by hindbrain herniation through the foramen magnum. Although the exact origin of congenital Chiari I malformation is unknown, it appears to be caused by a mismatch between the volume of the posterior fossa neural elements and the posterior fossa cranial content. Several theories have been proposed to describe the resultant pathophysiology of this mismatch. It is clear, however, that abnormal cerebrospinal fluid flow and velocity play a role in the symptoms and signs associated with this disorder. The authors will review the pathophysiology, clinical presentation, and treatment options for patients with Chiari I malformation.
Analysis of magnetic resonance imaging–based blood and cerebrospinal fluid flow measurements in patients with Chiari I malformation: a system approach
Authors: Alperin Noam , Kulkarni Kirti , Roitberg Ben , Loth Francis , Pandian Naren K. , Mafee Mahmood F. , Foroohar Mina , Lichtor Terry
Published: January 2008

Object

A pilot study was performed to assess noninvasively the change in intracranial compliance (ICC) and intracranial pressure (ICP) in patients with Chiari I malformation who undergo foramen magnum decompression. The working hypothesis was that the main effect of the decompressive surgery is a change in ICP. Noninvasive cine phase-contrast magnetic resonance (MR) imaging is a motion-sensitive dynamic MR imaging technique that allows for visualization and quantitation of tissue motion and flow. The authors' group has used dynamic phase-contrast MR imaging to visualize and quantify pulsatile blood and cerebrospinal fluid (CSF) flow in the craniospinal system.

Methods

A system approach has been used to characterize the hemodynamic–hydrodynamic coupling in the craniospinal system and to derive measures for ICC and ICP. Magnetic resonance imaging–based ICC and ICP values are derived from the ratio of the volume and pressure changes that occur naturally during each cardiac cycle. The authors conducted a prospective study of four patients, three of whom were studied before and after decompressive surgery; significant change in MR imaging–derived ICC and ICP values was documented in only one of the three surgically treated patients. A significant change in the dynamics of the intracranial volume change (ICVC) during the cardiac cycle, however, was observed in all three patients. In healthy individuals the ICVC waveform usually consists of the following sequence: monotonic increase in intracranial volume (ICV) during the systolic phase due to increased blood inflow, monotonic decrease in ICV caused by the onset of CSF outflow into the spinal canal, and increase in the venous outflow. A nonmonotonic decline in the ICVC waveform has been observed in all patients with headaches, and a relatively normal waveform was found in those without headaches or whose headaches were resolved or alleviated by the surgery. A “partial-valve” mechanism is proposed as an explanation for the abnormal ICVC dynamics. The monotonic decline in ICVC is interrupted by a “premature” reduction in the CSF outflow. This may be caused by a displacement of the hindbrain into the cervical spinal canal during the systolic phase. This obstructs the CSF flow at the later part of the systolic phase such that the ICV does not continue its gradual decline. Postsurgery, the ICVC waveforms presented a more normal-appearing ICVC dynamics profile.

Conclusions

Magnetic resonance imaging measurement of transcranial CSF and blood flow may lead to a better understanding of the pathophysiology of Chiari malformations and may prove to be an important diagnostic tool for guiding for the treatment of patients with Chiari I malformation.
Intracranial intraosseous hydatid cyst
Authors: Erman Tahsin , Tuna Metin , Göçer İskender , İldan Faruk , Zeren Mustafa , Çetinalp Erdal
Published: January 2008

Cerebral hydatidosis accounts for approximately 1 to 3% of all cases of hydatid disease. Generally, cerebral hydatid cysts are single lesions located in the watershed of the middle cerebral artery. Primary intracranial extracerebral hydatid cysts are extremely rare. Only 2% of hydatid cysts are localized in the skeleton, and of these 3 to 4% are found in the skull. The authors describe the case of a 10-year-old boy who was admitted to their clinic with headache and unilateral focal epileptic seizures. Computerized tomography scanning revealed a right parietal intraosseous hydatid cyst. A case of cranial intraosseous hydatid disease is presented, and the differential diagnosis and treatment are discussed in the light of literature.
Brief history of surgical timing: surgery for ruptured intracranial aneurysms
Authors: Stein Sherman C.
Published: January 2008

The neurosurgical profession has taken a circuitous route to attain its current knowledge about timing for aneurysm surgery. While addressing the timing issue, neurosurgeons were beset by many pressures simultaneously. They were forced to justify not only optimal surgical techniques but the need for surgery at all in the treatment of ruptured aneurysms. The beliefs of surgeons with strong personalities, in addition to intuitive guesses, often served to guide surgery in the absence of scientific evidence. That any progress could be made against a background of desperately ill patients and frustrating early results is remarkable. The author briefly outlines the controversies and misdirection that accompanied this progress toward understanding surgical timing in the treatment of ruptured aneurysms.
Ibn Sina (Avicenna)
Authors: Sarrafzadeh Asita S. , Sarafian Nuri , von Gladiss Almut , Unterberg Andreas W. , Lanksch Wolfgang R.
Published: January 2008

Ibn Sina (often known by his last name in Latin, Avicenna; 980–1037 A.D.) was the most famous physician and philosopher of his time. His Canon of Medicine, one of the most famous books in the history of medicine, surveyed the entire medical knowledge available from ancient and Muslim sources and provided his own contributions. In this article the authors present a unique picture of the neurosurgical technique of Ibn Sina and briefly summarize his life and work.
The Zeiss-MKM system for frameless image-guided approach in epidural motor cortex stimulation for central neuropathic pain
Authors: Pirotte Benoit , Voordecker Philippe , Joffroy Freddy , Massager Nicolas , Wikler David , Baleriaux Danielle , Levivier Marc , Brotchi Jacques
Published: January 2008

Object

Twelve patients (seven female, and five male, mean age 55.6 years) suffering from refractory central (ischemic/traumatic [eight cases]) and neuropathic pain (trigeminal neuropathy [four cases]) underwent surgery for the implantation of an epidural motor cortex stimulation (MCS) device in which the authors used a frameless neuronavigation system, the Zeiss-MKM microscope.

Methods

The authors assessed the spatial accuracy of the neuronavigation system and its potential contribution to improve the quality of targeting pain. In these patients, the positions of the central sulcus, defined by stereotactic magnetic resonance MR imaging, intraoperative somatosensory evoked potentials (SSEPs) and subdural visual verification, were correlated into the stereotactic neuronavigation planning procedure. The mean spatial accuracy of distance between (MR) imaging–defined and actual central sulcus was 2.4 mm (range 5–10 mm). The intraoperative SSEP-defined central sulcus was close to that defined by MR imaging (mean distance 6.4 mm). Although very precise, intra-operative SSEP recordings were impaired by artifacts and wave attenuation in six of the 12 patients. Stereotactic correlations between anatomical and functional data in the navigation system corrected final targeting in 10 of 12 cases. Pain relief was obtained in eight patients. Indeed, inappropriate targeting probably explains the reported variable success rate of MCS and certainly underestimates the actual efficacy.

Conclusions

Since intraoperative SSEP monitoring has, for many years, been considered the standard procedure to approach motor target, the development of an accurate stereotactic image guidance system could help to increase the efficacy of MCS on the alleviation of pain. The excellent spatial accuracy provided by the Zeiss-MKM navigation system allows precise data correlations that represent a remarkable means to validate functional MR imaging as an alternative to SSEP. The authors believe that developing stereotactic image guidance with such a navigation system could improve the success rate of MCS.
Terson's syndrome in subarachnoid hemorrhage and severe brain injury accompanied by acutely raised intracranial pressure
Authors: Medele Ralph J. , Stummer Walter , Mueller Arthur J. , Steiger Hans-Jakob , Reulen Hans-Jürgen
Published: January 2008

Object

The syndrome of retinal or vitreous hemorrhage in association with subarachnoid hemorrhage (SAH) is known as Terson's syndrome. The authors' purpose was to determine whether intraocular hemorrhage occurs with similar incidence when caused by severe brain injury accompanied by acutely raised intracranial pressure (ICP).

Methods

Prospective ophthalmological examination was performed in 22 consecutive patients with SAH or severe brain injury and elevated ICP. Thirteen patients were admitted for SAH (World Federation of Neurological Surgeons Grades II–IV) and nine for severe brain injury (Glasgow Coma Scale scores 3–10). Monitoring of ICP was performed at the time of admission via a ventricular catheter. Initial ICP exceeded 20 mm Hg in all patients. Indirect ophthalmoscopy without induced mydriasis was performed within the 1st week after the acute event. Retinal or vitreous hemorrhage was seen in six (46%) of 13 patients with SAH and in four (44%) of nine patients with severe brain injury. Ocular bleeding was found bilaterally in three patients with SAH and in one patient with severe brain injury (18%). Six of the 10 patients with Terson's syndrome died as a result of their acute event.

Conclusions

The present results indicate that Terson's syndrome may be related to acute elevation of ICP, independent of its causes, and may occur with similar incidence in patients with severe brain injury and those with SAH. Because recognition and treatment of Terson's syndrome may prevent visual impairment and associated secondary damage to the eye, increased awareness of this entity in all patients with acute raised intracranial hypertension is recommended.
Neuropsychological function and brain arteriovenous malformations: redefining eloquence as a risk for treatment
Authors: Lazar Ronald M.
Published: January 2008

Arteriovenous malformations (AVMs) of the brain, thought to begin during fetal development and undergo an unclear maturation process; most often do not become symptomatic until the patient reaches adulthood. Authors of recent prospective studies have suggested that relatively few patients present with neuropsychological abnormalities in the absence of hemorrhage. In general, neuropsychological evaluations in patients with AVMs have yielded mixed results with respect to localization of function, and the authors of most cognitive studies have not been able to demonstrate the nature and degree of impairment seen in acute ischemic stroke in comparable brain regions. Superselective Wada testing prior to therapeutic embolization, functional imaging studies, and intrasurgical cortical mapping have shown redistribution of language and memory to unpredictable regions. Developmental cognitive history in these patients indicates that most will have at least some background of learning problems during the school-age years with varying degrees of severity, reflecting a time when brain reorganization may be occurring. These data suggest that traditional assumptions about the eloquence of brain regions may not hold for patients with AVMs and that establishing treatment risk in the individual patient needs to be made on an empirical basis.
Anesthesia-related considerations for cerebral arteriovenous malformations
Authors: Hashimoto Tomoki , Young William L.
Published: January 2008

In the optimum anesthetic management of patients with cerebral arteriovenous malformations (AVMs), the anesthesiologist should be familiar with the general pathophysiology of these lesions and various strategies for treatment. In this review, the authors outline these issues with special attention to cerebral hemodynamic changes induced by AVMs and their resection.
Decision analysis for small, asymptomatic intracranial arteriovenous malformations
Authors: McInerney James , Gould David A. , Birkmeyer John D. , Harbaugh Robert E.
Published: January 2008

Object

Asymptomatic intracranial arteriovenous malformations (AVMs) represent a clinically challenging problem because of the complex decision making that must be undertaken prior to beginning any type of treatment. In addition, the relative infrequency of these lesions means that there is relatively little experience reported in the literature. The authors use a decision-analysis technique to model the considerations that go into determining the treatment of these lesions in an effort to quantify the various risks and overall benefits conferred by the following three treatment strategies: observation/natural history, microsurgery, and stereotactic radiosurgery.

Methods

The authors conducted a thorough literature search to elucidate the risks and outcomes associated with each treatment option. These values were used to build and run a comprehensive Markov model to determine a base-case analysis. All of the input variables were also subjected to sensitivity analysis to identify the most influential input variables and the crossover points in which favored strategies changed.

The base-case analysis suggested that microsurgery was the favored treatment option because this hypothetical cohort accumulated 21.53 quality-adjusted life years (QALYs) over the course of the model compared with the 16.97 QALYs and 16.40 QALYs for stereotctic radiosurgery and observation, respectively. Sensitivity analysis demonstrated that overall major neurological morbidity and mortality were the most influential input variables both perioperatively and during the radiosurgical “latent” period (that is, up to 2 years posttreatment). The maximum acceptable perioperative combined major neurological morbidity and mortality rate was 6.8%. The latent period combined major neurological morbidity and mortality would need to be 0.7% to make radiosurgery favorable in this analysis.

Conclusions

Results of this decision analysis model suggest that microsurgery in the hands of experienced cerebrovascular surgeons, who can expect a less than 6.8% combined rate of major neurological morbidity and mortality, offers patients a greater overall quality of life over time.
The role of vertebroplasty in metastatic spinal disease
Authors: Pilitsis Julie G. , Rengachary Setti S.
Published: January 2008

Many advances have been made in the treatment of metastatic spinal disease over the last few decades. Radiotherapy offers benefit and pain relief to many patients; however, this modality provides minimal vertebral stabilization. Surgical management consists of decompression and complex fusions. Vertebroplasty offers an adjuvant therapy to both radiotherapy and surgery by providing additional stabilization and pain relief. The results of case studies suggest that including vertebroplasty in the management of these patients is beneficial. In this article the authors review the role of vertebroplasty in metastatic spinal disease.
Image-guided radiosurgery in the treatment of spinal metastases
Authors: Murphy Martin J. , Chang Steven , Gibbs Iris , Le Quynh-Tu , Martin David , Kim Daniel
Published: January 2008

Object

The authors describe a new method for treating metastatic spinal tumors in which noninvasive, image-guided, frameless stereotactic radiosurgery is performed. Stereotactic radiosurgery delivers a high dose of radiation in a single or limited number of fractions to a lesion while maintaining delivery of a low dose to adjacent normal structures.

Methods

Image-guided radiosurgery was developed by coupling an orthogonal pair of real-time x-ray cameras to a dynamically manipulated robot-mounted linear accelerator that guides the radiation beam to treatment sites associated with radiographic landmarks. This procedure can be conducted in an outpatient setting without the use of frame-based skeletal fixation. The system relies on skeletal landmarks or implanted fiducial markers to locate treatment targets. Four patients with spinal metastases underwent radiosurgery with total prescription doses of 1000 to 1600 cGy in one or two fractions. Alignment of the treatment dose with the target volume was accurate to within 1.5 mm. During the course of each treatment fraction, patient movement was less than 0.5 mm on average. Dosimetry was highly conformal, with a demonstrated ability to deliver 1600 cGy to the perimeter of an irregular target volume while keeping exposure to the cord itself below 800 cGy.

Conclusions

These experiences indicate that frameless radiosurgery is a viable therapeutic option for metastatic spine disease.
Ultrasonographic guidance for spinal extracranial radiosurgery: technique and application for metastatic spinal lesions
Authors: Ryken Timothy C. , Meeks Sanford L. , Traynelis Vincent , Haller John , Bouchet Lionel G. , Bova Francis J. , Pennington Edward C. , Buatti John M.
Published: January 2008

Object

The relatively stationary anatomy of the intracranial compartment has allowed the development of stereotactic radiosurgery as an effective treatment option for many intracranial lesions. Difficulty in accurately tracking extracranial targets has limited its development in the treatment of these lesions. The ability to track extracranial structures in real time with ultrasound images allows a system to upgrade and interface pretreatment volumetric images for extracranial applications. In this report the authors describe this technique as applied to the treatment of localized metastatic spinal disease.

Methods

The extracranial stereotactic system consists of an optically tracked ultrasonography unit that can be registered to a linear accelerator coordinate system. Stereotactic ultrasound images are acquired following patient positioning, based on a pretreatment computerized tomography (CT) simulation. The soft-tissue shifts between the virtual CT-based treatment plan and the actual treatment are determined. The degree of patient offset is tracked and used to correct the treatment plan.

The ultrasonography-based stereotactic navigation system is accurate to within an approximate means of 1.5 mm based on testing with an absolute coordinate phantom. A radiosurgical treatment was delivered using the system for localization of a metastatic spinal lesion. Compared with the virtual CT simulation, the actual treatment plan isocenter was shifted 12.2 mm based on the stereotactic ultrasound image. The patient was treated using noncoplanar beams to a dose of 15.0 Gy to the 80% isodose shell in a single fraction.

Conclusions

A system for high-precision radiosurgical treatment of metastatic spinal tumors has been developed, tested, and applied clinically. Optical tracking of the ultrasonography probe provides real-time tracking of the patient anatomy and allows computation of the target displacement prior to treatment delivery. The results reported here suggest the feasibility and safety of the technique.
New double-door laminoplasty procedure for the axis to preserve all muscular attachments to the spinous process
Authors: Shiraishi Tateru , Yato Yoshiyuki
Published: January 2008

To prevent the occurrence of postoperative cervical malalignment, which is often a complication of conventional axial laminectomy or laminoplasty, the authors developed a new double-door laminoplasty procedure in which the C-2 spinal canal is expanded while all the muscular attachments to each split half of the spinous process remain undisturbed. In conjunction with laminoplasties at other levels, this procedure was performed in five patients with ossification of the posterior longitudinal ligament and cervical myelopathy. Neurological improvement was demonstrated in each patient, and there was no radiological evidence of cervical malalignment. The technique for this procedure is described and its usefulness in preventing postoperative spinal malalignment is discussed.
Anterior decompression for cervical spondylosis associated with an early form of cervical ossification of the posterior longitudinal ligament
Authors: Mizuno Junichi , Nakagawa Hiroshi
Published: January 2008

Object

The goal of this study was to determine the appropriate surgical strategy for cervical spondylosis associated with an early form of ossification of the posterior longitudinal ligament (EOPLL) of the cervical spine.

Methods

Patients with EOPLL-associated cervical spondyosis were selected for treatment. Medical records and radiographs were retrospectively reviewed. Specimens taken at the time of operation were histologically examined. There were 24 men and six women ranging in age from 39 to 74 years (mean 57.6 years). Symptoms consisted of myelopathy in 28 cases and radiculopathy in two cases. Anterior decompressive surgery was performed. The EOPLL, hypertrophy of the posterior longitudinal ligament (HPLL), and the disc–PLL complex were directly resected. The mean preoperative Japan Orthopaedic Association score was 12.6, and the mean postoperative score was 14.4. Histologically, EOPLL was consistent with foci of compact lamellar bone in the degenerative thickening of the PLL.

Conclusions

Appropriate corpectomy should follow direct removal of EOPLL associated with HPLL compressing the spinal cord to achieve good outcomes.
Early results using the Atlantis anterior cervical plate system
Authors: Barnes Bryan , Haid Regis W. , Rodts Gerald , Subach Brian , Kaiser Michael
Published: January 2008

Object

The authors present a retrospective review of 77 patients in whom they performed anterior cervical discectomy and fusion (ACDF) in the treatment of radiculopathy and/or myelopathy. In all cases anterior interbody fusion was performed using the Atlantis locking plate system to treat the degenerative disease.

Methods

There were 41 men and 36 women (mean age 53.8 years), and 24 active cigarette smokers (31%) in the group. All patients presented with signs and symptoms of cervical radiculopathy and/or myelopathy, and magnetic resonance imaging or computerized tomography myelography demonstrated evidence of radicular and/or spinal cord compression at one or more cervical levels. Thirty-one patients underwent single-level ACDF, 20 patients underwent multilevel ACDF without posterior instrumentation, in eight patients one- to four-level corpectomies were supplemented with posterior fixation, 12 patients underwent single-level corpectomy, and six patients underwent multilevel corpectomy with no posterior instrumentation. The mean follow-up period was 15.33 months; overall good-to-excellent outcome was seen in 75% of patients; osseous fusion was demonstrated in 93.5%. In all patients except three, fibular allograft was used as graft material.

The degree of overall cervical lordosis was measured at the last follow up and was compared with normal values obtained in age-matched individuals. In addition, the degree of cervical lordosis at fusion levels was compared with overall cervical lordosis. In patients in all five of the aforementioned categories significantly less lordosis was demonstrated than in age-matched controls. In patients who underwent single-level ACDF, single-level corpectomy, and multilevel ACDF significantly less lordosis was observed at the fusion segment than that in the overall cervical spine.

Complications included one episode of chronic anterior wound drainage treated with intravenous antibiotic medication and one postoperative posterior wound infection, which required reoperation and intravenous antibiotic medication. Two cases (2.6%) of anterior screw backout and/or breakage were identified. One patient died of unrelated causes within 3 months of operation.

Conclusions

These initial results indicate that use of the Atlantis plate system for anterior cervical arthrodesis produces fusion rates and clinical outcomes that are comparable with those obtained using other locking plating systems. It has the unique advantage, however, of providing the surgeon with the choice of fixed, variable, or hybrid screw constructs as a way of tailoring screw angles to individual anatomical/biomechanical needs.
Ganglionectomy of C-2 for the treatment of medically refractory occipital neuralgia
Authors: Wang Michael Y , Levi Allan D. O.
Published: January 2008

Occipital neuralgia is a result of neuropathic pain transmission in the distribution of the greater occipital nerve. Because it is well anatomically localized, occipital neuralgia has been the focus of various surgical treatments. Ablation, decompression, and modulation of the C-2 nerve have all been described as effective treatments. The C-2 dorsal root ganglionectomy provides effective treatment for this disorder with a low incidence of unpleasant side effects. In this review the authors summarize the current treatment of occipital neuralgia.
Two-level anterior cervical discectomy and cage-assisted fusion without plates
Authors: Assietti Roberto , Beretta Federica , Arienta Cesare
Published: January 2008

Object

Anterior cervical discectomy (ACD) is an effective and safe treatment for nerve root or spinal cord compression caused by disc herniation or spondylosis. Cervical interbody fusion allows preservation of the physiological lordosis and stability of the cervical spine. Based on data reported in the literature, fusion rates decrease significantly when more than one level undergoes surgery, and some authors recommend the addition of a plate system to improve results. At the authors' institution cervical carbon fiber cages (CFCs) are routinely used after ACD. They describe their experience in the treatment of 24 patients with two-level disease treated with CFCs alone.

Methods

Twenty-one patients with cervical radiculopathy and three with radiculomyelopathy underwent ACD. Surgery was performed at C5–6 and C6–7 in 18, at C4–5 and C5–6 in four, and at C3–4 and C5–6 in two patients. All the patients underwent magnetic resonance imaging and 15 also underwent computerized tomography (CT) to assess the results of surgery.

Radiculopathy improved after surgery in all the cases, whereas myelopathy resolved in only one patient. At 1 year fusion was achieved in 96% of the surgically treated discs; this was verified on cervical spine x-ray films in all patients and on CT scans in three patients. Cervical lordosis was restored in eight of the nine patients in whom it was lost preoperatively. No complications related to cage extrusion and no cases of symptomatic pseudarthrosis were observed.

Conclusions

Interbody fusion cages have a load-sharing function and stabilize the spine to increase segmental stiffness, thus achieving fusion rates similar to those associated with bone grafts, even in multilevel disease.
Comparative evaluation of microdiscectomy only, autograft fusion, polymethylmethacrylate interposition, and threaded titanium cage fusion for treatment of single-level cervical disc disease: a prospective randomized study in 125 patients
Authors: Bärlocher Christian B. , Barth Alain , Krauss Joachim K. , Binggeli Ralph , Seiler Rolf W.
Published: January 2008

Object

The need for interbody fusion or stabilization after anterior cervical microdiscectomy is still debated. The objectives of this prospective randomized study were 1) to examine whether combined interbody fusion and stabilization is more beneficial than microdiscectomy only (MDO) and 2) if fusion is found to be more beneficial than MDO, to determine which is the best method of fusion by comparing the results achieved using autologous bone graft (ABG), polymethylmethacrylate (PMMA) interposition, and threaded titanium cage (TTC).

Methods

A total of 125 patients with a single-level cervical disc disease were included in this prospective study. All patients were randomized and assigned to one of the four following groups: Group 1 (33 patients), MDO; Group 2 (30 patients), microdiscectomy followed by ABG; Group 3 (26 patients), microdiscectomy followed by injection of PMMA; and Group 4 (36 patients), microdiscectomy followed by placement of a TTC. Clinical outcome according to Odom criteria was summarized as 1) excellent and good or 2) satisfactory and poor. One-year follow-up examination was performed in 123 patients. Patients in the TTC group experienced a significantly better outcome 6 months after surgery (92% excellent and good results) compared with those in the MDO and ABG groups (72.7 and 66.6% excellent and good results, respectively). Twelve months after surgery there was still a significant difference in outcomes between the TTC group (94.4% excellent and good results) and the MDO group (75.5% excellent and good results). Outcome in patients treated with PMMA was comparable with that in those treated with TCC after 6 (91.6%) and 12 months (87.5%), but no segmental fusion was achieved. Differences compared with MDO and ABG were, however, not significant, which may be related to the smaller number of patients in the PMMA group.

Conclusions

Interbody cage-assisted fusion yields a significantly better short- and intermediate-term outcome than MDO in terms of return to work, radicular pain, Odom criteria, and earlier fusion. In addition, the advantages of interbody cages over ABG fusion included better results in terms of return to work, Odom criteria, and earlier fusion after 6 months. These results suggest that interbody cage–assisted fusion is a promising therapeutic option in patients with single-level disc disease. Polymethylmethacrylate seems to be a good alternative to interbody cage fusion but is hindered by the absence of immediate fusion.
Atlantal lateral mass screws for posterior spinal reconstruction
Authors: Fiore Amory J. , Haid Regis W. , Rodts Gerald E. , Subach Brian R. , Mummaneni Praveen V. , Riedel Charles J. , Birch Barry D.
Published: January 2008

Object

A variety of techniques may be used to achieve fixation of the upper cervical spine. Transarticular atlantoaxial screws, posterior interspinous cable and graft constructs, and interlaminar clamps have been used effectively to achieve atlantoaxial fixation. Various anatomical factors, however, may preclude the successful application of these techniques. These factors include aberrant vertebral artery anatomy, irreducible atlantoaxial subluxation, exaggerated cervicothoracic kyphosis, and the absence of the osseous substrate for fixation. In these cases, an alternative method of fixation must be performed. The authors present an alternative method to achieve fixation of the atlas in which lateral mass screws can be applied to atlantoaxial and occipitocervical fixation.

Methods

Between February 1998 and November 2001, eight patients who ranged in age from 16 to 74 years underwent posterior fixation for upper cervical instability. Diagnoses included C-2 metastastic disease in two patients, irreducible odontoid fractures in two patients, atlantoaxial subluxation in two patients, and transverse ligament synovial cyst in two patients. Various anatomical factors precluded transarticular atlantoaxial screw fixation in seven patients. One patient with a highly unstable spine due to a C-2 metastasis and pathological fracture underwent occipitocervical fusion.

Atlantocervical fixation was achieved in seven patients by using varying constructs incorporating C-1 lateral mass screws. Occipitocervical fixation was achieved in one patient by incorporating C-1 lateral mass screws as an additional fixation point. A total of 14 C-1 lateral mass screws were placed in eight patients. There were no intraoperative complications. In all patients rigid fixation was achieved as demonstrated on postoperative radiographs. One patient died on postoperative Day 9 of aspiration pneumonia. At a mean follow-up time of 7.4 months, rigid fixation was maintained in all patients.

Conclusions

Atlantal lateral mass screws can be used to provide a safe and efficacious means of achieving atlantoaxial fixation when anatomical constraints preclude the use of a more traditional procedure. Atlantal lateral mass screws may also be incorporated in occipitocervical constructs to provide additional fixation points which may prevent construct failure.
Posterior atlantoaxial stabilization: new alternative to C1–2 transarticular screws
Authors: Stokes John K. , Villavicencio Alan T. , Liu Paul C. , Bray Robert S. , Johnson J. Patrick
Published: January 2008

Object

Surgical treatment of atlantoaxial instability has evolved to include various posterior wiring techniques including Brooks, Gallie, and Sonntag fusions in which success rates range from 60 to 100%. The Magerl–Seemans technique in which C1–2 transarticular screws are placed results in fusion rates between 87 and 100%. This procedure is technically demanding and requires precise knowledge of the course of the vertebral arteries (VAs). The authors introduce a new C1–2 fixation procedure in which C-1 lateral mass and C-2 pedicle screws are placed that may have advantages over C1–2 transarticular screw constructs.

Methods

A standard posterior C1–2 exposure is obtained. Polyaxial C-2 pedicle screws and C-1 lateral mass screws are placed bilaterally. Rods are connected to the screws and secured using locking nuts. A cross-link is then placed. Fusion can be performed at the atlantoaxial joint by elevating the C-2 nerve root.

The technique for this procedure has been used in four cases of atlantoaxial instability at the author's institution. There have been no C-2 nerve root– or VA-related injuries. No cases of construct failure have been observed in the short-term follow up period.

Conclusions

Atlantoaxial lateral mass and axial pedicle screw fixation offers an alternative means of achieving atlantoaxial fusion. The technique is less demanding than that required for transarticular screw placement and may avoid the potential complication of VA injury. The cross-linked construct is theoretically stable in flexion, extension, and rotation. Laminectomy or fracture of the posterior elements does not preclude use of this fixation procedure.
Anterior cervicothoracic junction corpectomy and plate fixation without sternotomy
Authors: Resnick Daniel K.
Published: January 2008

Object

Exposure of the lower cervical and upper thoracic spinal regions through a cervical incision without sternotomy has been described in cases of anterior decompression and methylmethacrylate vertebral body reconstruction. The use of anterior instrumentation and structural bone grafts in this procedure has not been well described.

Methods

Twenty-one patients underwent anterior cervicothoracic decompression, fusion, and fixation via a low cervical approach. Eight of these patients underwent lower cervical or upper thoracic corpectomy (C7–T4) through the cervical incision. The decompressive procedure was followed by placement of an allograft bone strut and an anterior locking plate system.

No patient developed new neurological deficit related to the spinal cord or exiting nerve roots. Three of four patients with preoperative neurological deficits improved dramatically. Two patients developed recurrent laryngeal nerve palsy, of which one was permanent. There was one case of instrumentation-related failure, and two patients developed a superficial wound infection related to a posterior incision made as part of a 360° fusion. Patients were followed for a mean of 18.5 months (range 2–30 months). Two patients died (of metastatic cancer, and a motor vehicle accident, respectively) during the follow-up period.

Conclusions

Anterior decompression, fusion, and fixation is feasible via a cervical incision. This procedural approach spares the patient the morbidity associated with sternotomy or the lateral extracavitary approach. A thorough preoperative assessment of mediastinal anatomy is essential for the safe execution of these procedures.
Low-grade central nervous system tumors
Authors: Lopes M. Beatriz S. , Laws Edward R.
Published: January 2008

Low-grade tumors of the central nervous system constitute 15 to 35% of primary brain tumors. Although this category of tumors encompasses a number of different well-characterized entities, low-grade tumors constitute every tumor not obviously malignant at initial diagnosis. In this brief review, the authors discuss the pathological classification, diagnostic procedures, treatment, and possible pathogenic mechanisms of these tumors. Emphasis is given in the neu-roradiological and pathological features of the several entities.
Results of halter cervical traction for the treatment of cervical radiculopathy: retrospective review of 81 patients
Authors: Olivero William C. , Dulebohn Scott C.
Published: January 2008

Object

The percentage of patients responding to conservative treatment for cervical radiculopathy secondary to nerve root compression is not well quantified. To clarify this question, the authors retrospectively reviewed the records obtained over a 4-year period in patients with cervical radiculopathy to determine their response to conservative measures (cervical collar therapy and halter cervical traction).

Methods

Cervical radiculopathy was diagnosed in patients if they suffered from radiating arm pain made worse by neck movement and at least one of the following: reflex loss, dermatomal numbness, and/or myotomal weakness. Patients with neck pain alone or arm pain without neurological deficit were excluded from analysis. Those patients without excruciating pain, severe weakness, or evidence of myelopathy were offered a course of halter traction before surgery was to be considered. Ninety-six patients met the inclusion criteria; there were 61 males and 35 females, and the mean age was 47 years. Fifty-five patients presented with C-7, 37 with C-6, two with C-5, and two with C-8 radiculopathy. Eighty-one patients underwent a trial of traction that consisted of wearing a cervical collar and home-based halter cervical traction: 8 to 12 pounds, applied for 15 minutes, three times a day for 3 to 6 weeks The mean duration of symptoms prior to neurosurgical evaluation was 43 days ± 8.3 days (standard deviation). Sixty-three (78%) of 81 patients responded to therapeutic traction, experiencing significant or total pain relief, three could not tolerate the traction, and traction failed in 15 patients. Of the 81 patients in whom traction was undertaken, 78 underwent magnetic resonance imaging prior to being seen, which revealed herniated discs at the corresponding levels in 71 and foraminal stenosis in seven. Three of the 63 patients in whom an initial response to traction was noted suffered recurrence of symptoms and required surgery. It would appear that in patients in whom symptoms of cervical radiculopathy were present for approximately 6 weeks that 75% will respond to further conservative treatment (halter traction and cervical collar) over the next 6 weeks.
Threat credibility and weapons of mass destruction
Authors: Moores Leon E.
Published: January 2008

Individual or collective preparedness for an attack involving weapons of mass destruction (WMD) must be based on an analysis of the threat. In threat assessment one takes many factors into account, including the physical and psychological parameters of the attacker. Although the potential devastation caused by WMD is significant, there are many limitations to the effective use of such weapons. Casualty rates will likely be measured in the thousands rather than millions because of factors that will be discussed. The psychological ramifications, it should be noted, the permutations of which have not yet been defined, will be much longer lasting. In this paper the author discusses these and other characteristics of the current threat.
Weapons of mass destruction: radiation
Authors: Neal Chris J. , Moores Leon E.
Published: January 2008

The purpose of this review is to present a concise overview of the types of radiation, methods of dispersal, injury patterns, and treatment considerations in a scenario involving radiation-based weapons of mass destruction. Radiation-related casualties, although uncommon, are a potential threat because more nations and organizations are developing the technology for producing radioactive substances capable of being used as weapons.
Neurosurgical practice in the current regulatory environment
Authors: Kusske John A.
Published: January 2008

The practice of neurosurgery has been complicated over the last 25 years by the enactment of a series of statutes that have significantly altered the time-honored means by which neurosurgeons manage their work. These laws deal with issues that neurosurgeons have not customarily had to consider. The author outlines some of the socioeconomic and political matters that led to the passage of these statutes. An assortment of the laws is then surveyed, to foster an appreciation for the variety and depth of health care law that affects neurosurgeons' practice and the delivery of care to their patients. Statutes discussed include the fraud and abuse laws, self-referral laws, the Emergency Medical Treatment and Labor Act, Health Insurance Portability and Accountability Act, and Employee Retirement Income Security Act.
Factors affecting profitability for craniotomy
Authors: Popp A. John , Scrime Todd , Cohen Benjamin R. , Feustel Paul J. , Petronis Karen , Habiniak Sharon , Waldman John B. , Vosburgh Margaret M.
Published: January 2008

Object

The authors studied factors influencing hospital profitability after craniotomy in patients who underwent craniotomy coded as diagnosis-related group (DRG) 1 (17 years of age with nontraumatic disease without complication) and who met their hospital's craniotomy pathway criteria and had a hospital length of stay 4 days or less during a 20-month period.

Methods

Data in all patients meeting these criteria (76 cases) were collected and collated from various hospital databases. Twenty-one cases were profitable and 55 were not. Variables traditionally influencing cost of care, such as surgeon, procedure, length of operation, and pharmacy use had no significant effect on whether a patient was profitable. The most important influence on profitability was the individual payor. Cases in which care was reimbursed under the prospective payment system based on DRGs were nearly always profitable whereas those covered by per diem plans were nearly always nonprofitable.

Conclusions

1) Hospital information systems should be customized to deliver consolidated data for timely analysis of cost of care for individual patients. This information may be useful in negotiating profitable contracts. 2) A clinical pathway was successful in reducing the difference in cost of care between profitable and nonprofitable postcra-niotomy cases. 3) In today's health care environment both cost containment and revenue assume importance in determining profitability.
Reconstruction of the skull base after tumor resection: an overview of methods
Authors: Liu James K. , Niazi Zahid , Couldwell William T.
Published: January 2008

Successful surgical management of malignant skull base tumors depends on both tumor resection and reconstruction of the cranial base defect. The primary goals of skull base reconstruction are to repair dural defects, to prevent the development of cerebrospinal fluid fistulas, and to provide a protective barrier that isolates the intracranial contents from the nasopharynx and paranasal sinuses. Failure to do so can result in potentially life-threatening infectious complications. With modern skull base and reconstructive techniques, malignant tumors in this region, which were once deemed inoperable, can now be safely removed. The authors review the different modalities available for skull base reconstruction following tumor resection.