bluuebunny/crossref_metadata_2025 huggingface dataset:
The central canal of the filum terminale in communicating hydrocephalus
Authors: Murthy Vijayashekara S. , Deshpande Dhirendra H.
Published: May 2009

✓ Lumbar thecoperitoneal shunting was carried out in patients with communicating hydrocephalus due to long-standing tuberculous meningitis. At the time of this surgical procedure, the filum terminale was excised to achieve filum terminostomy. The central canal of the excised filum terminale in seven hydrocephalic children and an equal number from control cases was studied histologically. These observations indicate that the central canal of the filum terminale dilates in communicating hydrocephalus, and the dilatation is proportionate to the lateral ventricular enlargement.
Physiological and behavioral changes produced by cerebellar stimulation in the monkey
Authors: Robertson Lee T. , Smith William L.
Published: May 2009

✓ Small surface electrodes were placed bilaterally over the intermediate or lateral cerebellar cortex of cynomolgus monkeys to determine how electrical stimulation of different areas of the cerebellar cortex affected average evoked responses and a sequential forelimb movement. Biphase electrical stimulation was applied between various electrode combinations, and various intensities and frequencies were established for each combination. Transcortical stimulation between the right and left intermediate cerebellar cortex required the lowest intensity (1.5 µC/sq cm/ph) to elicit an average evoked response in the sensorimotor cortex; stimulation between the electrodes over the contralateral intermediate or lateral cortex required slightly higher levels (2.0 µC/sq cm/ph). No response could be elicited from stimulating the ipsilateral cortex. Likewise, 1 minute of transcortical stimulation was more effective than comparable stimulation of the contralateral intermediate or lateral cortex in altering the waveforms of a somatosensory evoked response. Transcortical stimulation also modified the forelimb movement, whereas contralateral stimulation of the intermediate or lateral cortex had little or no effect. Transcortical stimulation at 2.0 µC/sq cm/ph, with frequencies of 150 Hz or higher, increased the time required to execute the forelimb movement but did not affect the accuracy of the movement. High-speed motion pictures indicated that transcortical stimulation decreased the velocity of forelimb movement and in some cases also affected the limb trajectory. These results indicate that consideration should be given to the area of the cerebellum stimulated and to the mode of stimulation, in the hope of achieving optimum clinical benefit.
Hydrocephalus and dementia complicating spinal tumor
Authors: Messer Henry D. , Brinker Ray A.
Published: May 2009

✓ Hydrocephalus and dementia associated with spinal mass lesions are well recognized. Removal of the spinal mass has sometimes resulted in relief of the dementia. This case demonstrates that the ventricular size may also become smaller after removal of the spinal mass.
Anterior sacral meningocele
Authors: Dyck Peter , Wilson Charles B.
Published: May 2009

✓ A woman presented with a mass in the left groin, which was later shown to be a sliding hernia. A bony sacral defect prompted investigation, which uncovered a massive anterior sacral meningocele. Examination, including ultrasonography and myelography, is discussed, and a surgical approach proposed.
CSF rhinorrhea from a transclival meningocele demonstrated with metrizamide CT cisternography
Authors: Lockwood Alan H. , Quencer Robert M. , Page Larry K.
Published: May 2009

✓ A 63-year-old woman with a 10-year history of intermittent cerebrospinal fluid (CSF) rhinorrhea was found to have a transclival meningocele. After pluridirectional tomography demonstrated a bone defect in the clivus, the diagnosis was established by means of computerized tomography (CT) by comparing the absorption coefficients of a soft-tissue mass within the sphenoid sinus before and after the injection of metrizamide into the lumbar subarachnoid space. An increase of 39 absorption units clearly indicated the movement of CSF from the prepontine subarachnoid space into the sphenoid sinus. This case illustrates the value of metrizamide CT cisternography in the evaluation of patients with CSF rhinorrhea.
Atypical fibrous histiocytoma in the skull of a infant
Authors: Black Samuel P. W. , Adelstein Edward , Levine Clive
Published: May 2009

✓ This is a report of an atypical fibrous histiocytoma in the skull of an infant, who at the age of 3 months was noted to have a “lump” beneath the scalp in the right parietal region. It was about 2 cm in diameter, and the scalp was movable over it. Physical examination was otherwise normal. Radiographs showed erosion of the skull deep to the palpable mass. At operation a neoplasm was found, which had destroyed the bone and invaded the adjacent temporal muscle and dura mater. The tumor was removed en bloc after the surrounding bone had been excised. Histological examination using light and electron microscopy revealed the tumor to be an atypical fibrous histiocytoma. Radiation therapy was not given. There has been no recurrence for 7 years.
An unusual presentation of an oligodendroglioma
Authors: Barrer Steven J. , Simeone Frederick A. , Han Soo S.
Published: May 2009

✓ The case reported is that of an oligodendroglioma presenting only as a lump on the forehead. A thin convex area of bone was found overlying the tumor.
Bitemporal hemianopsia associated with sclerosis of the intracranial internal carotid arteries
Authors: Matsuo Koichi , Kobayashi Shigeaki , Sugita Kenichiro
Published: May 2009

✓ A case of bitemporal hemianopsia in a 68-year-old woman is reported. Surgical exploration revealed bilateral compression of the optic nerves by the arteriosclerotic internal carotid arteries. Microsurgical decompression with unroofing of the optic canals resulted in prompt recovery of the visual fields.
Anterior spinal artery aneurysm
Authors: Yonas Howard , Patre Sue , White Robert J.
Published: May 2009

✓ An anomaly of the anterior spinal artery in association with a berry aneurysm is reported. The embryological basis for this previously unreported combination is reviewed.
Acrylic spinal fusion
Authors: Hansebout Robert R. , Blomquist Gustav A.
Published: May 2009

✓ Methyl methacrylate (acrylic) was used in fusion techniques in 82 patients, most of whom had metastatic disease, between 1959 and 1979. In all cases the acrylic was used to supplement stabilization with Meurig-Williams stainless steel plates or with wire. In cases involving a decompressive laminectomy and excisional biopsy (radical resection of a tumor mass) that required posterior stabilization, acrylic helped to achieve rapid fusion with excellent results. The series included one anterior fusion with acrylic and nine atlantoaxial fusions in patients without tumors. Strict guidelines for selection of patients are outlined. The advantage of acrylic over bone fusion in selected patients is discussed. Careful follow-up studies including autopsy examinations are included. The technique of the use of acrylic is outlined.

There was no case of late instability. There was one instance of infection in a patient who was immunodeficient and in whom a combination acrylic and bone fusion was performed. Tissue reaction to the acrylic in autopsy specimens is discussed.
Interstitial brachytherapy of primary brain tumors
Authors: Hosobuchi Yoshio , Phillips Theodore L. , Stupar Terry A. , Gutin Philip H.
Published: May 2009

✓ Ten patients harboring inaccessible, slow-growing or recurrent malignant primary brain tumors were treated by the stereotaxic implantation of a radionuclide seed — iridium-192 (192Ir) or gold-198 (198Au) — either permanent or removable. The strength for 192Ir seeds was selected to deliver 10,000 to 12,000 rads to the periphery of the tumor, and that for 198Au seeds to deliver 4000 to 7500 rads. Three of the six patients treated with 192Ir showed objective responses lasting 8, 11, and 12 months, respectively; and one patient's disease stabilized for 18 months. Three of the four treated with 198Au showed responses lasting 5 months, 6 months, and 2 years, respectively. Because of the higher dose-rate attainable with 198Au, removable implants of this material are more effective against the faster-growing malignant tumors.

Another radionuclide, iodine-125 (125I), is now being tested against brain tumors. The radioactivity of 125I is high; but because its gamma emission is less energetic by a factor of 10 than that of 198Au or 192Ir, its radiation field is concentrated within a radius of 2.5 cm or less. This low-energy gamma emission also makes it easier to protect medical personnel and the patients' families against the nuclide when 125I is used.
Psychological changes following surgery for tumors in the temporal lobe
Authors: Cavazzuti Valeria , Winston Ken , Baker Richard , Welch Keasley
Published: May 2009

✓ Twenty patients with a tumor in the temporal lobe underwent extensive neuropsychological testing pre- and postoperatively, with special regard to verbal and nonverbal memory. All patients had bilateral abnormalities preoperatively. Contralateral functions tended to improve after surgery, contrary to the outcome expected in patients with bilateral abnormalities due to atrophic lesions. Computerized tomography was the most useful neurodiagnostic test in correctly identifying the nature of the lesion in these patients.
Carcinoembryonic antigen in cerebrospinal fluid of adult brain-tumor patients
Authors: Hill Stephen , Martin Edward , Ellison E. C. , Hunt William E.
Published: May 2009

✓ Carcinoembryonic antigen (CEA) was measured in plasma and cerebrospinal fluid (CSF) in patients with neoplasms and non-neoplastic neurologic conditions of the central nervous system (CNS). Seventy-two control patients had a mean CEAcsf of 0.04 ng/cu cm, 31 patients with benign tumors had a mean CEAcsf of 0.03 ng/cu cm, and 21 patients with malignant CNS tumors had mean CEAcsf of 21.7 ng/cu cm. In the absence of intradural metastasis, the existence of non-CNS malignancies did not cause CEA to appear in the CSF. There was no relationship between the plasma and CSF levels of CEA. The CSF is normally free of CEA, and its detection is strongly suggestive of either primary or secondary intradural malignancy. The titres of CEA decline with effective therapy, and may be of use in monitoring treated patients for recurrence.
Bacterial intracranial aneurysms
Authors: Frazee John G. , Cahan Leslie D. , Winter James
Published: May 2009

✓ The treatment of 13 patients with bacterial intracranial aneurysms is reported. The incidence of bacterial intracranial aneurysms was 4% of all patients admitted with intracranial aneurysms and 3% of all patients admitted with bacterial endocarditis. Each patient had neurological signs or symptoms suggestive of intracranial disease prior to the diagnosis of an aneurysm. Alpha Streptococcus was the most common infecting organism. All patients were treated with specific, high-dose antibiotics, and five patients underwent surgery as well. There were no surgical deaths. Six of eight nonsurgically treated patients died. A review of the literature confirms a high mortality for patients treated with only antibiotics, and a low mortality for elective surgery. The authors conclude that 1) patients with bacterial endocarditis, who develop sudden severe headache, focal neurological signs or symptoms, or seizures, should undergo serial cerebral angiography every 7 to 10 days throughout their hospitalization; 2) if an aneurysm is identified it should be excised whenever possible; and 3) patients with proximal or multiple aneurysms should be considered for surgery.
Neonatal intracranial hemorrhage
Authors: Leblanc Richard , O'Gorman Augustin M.
Published: May 2009

✓ Forty-six neonates with intracranial hemorrhage were classified into three groups on the basis of the major computerized tomography (CT) scan findings: Group I consisted of 24 cases of subarachnoid hemorrhage, Group II 20 cases of intracerebral and/or intraventricular hemorrhage, and Group III two cases of subdural hemorrhage. The initial scans in Group I showed blood in the interhemispheric fissure and the supratentorial recess. Sixty percent had an associated hypodensity in the frontal and/or parietal areas, thought to be an indication of ischemia. Changes in the configuration of the ventricular system were infrequent. Initial scans in Group II showed hematomas as follows: one in the brain stem, five in the basal ganglia, 10 in the temporal lobes, and 11 in the ventricles. In 70% of these cases, changes in the configuration of the ventricular system were seen, including compression of a lateral ventricle by mass effect, ventricular dilatation with blood, and obstructive hydrocephalus. Subarachnoid blood was an associated finding in 55% of cases, and focal and diffuse cerebral edema in 40%. Scans in both Group III patients initially showed a mass effect from a subdural clot. In all, 30 patients had one or more follow-up CT scans, and 13 of these were scanned at regular intervals. None of the Group I patients developed hydrocephalus, but 85% of Group II patients with intraventricular blood extending from an intracerebral hemorrhage had this complication. A seizure disorder occurred in 31% of Group I patients and 20% of Group II patients, where it was seen exclusively in those with an intralobar hematoma. A major motor disturbance occurred in 16% of patients; their CT scans showed evidence of brain destruction involving enlargement of a lateral ventricle, porencephaly, or focal atrophy. Computerized tomography is a useful adjunct to the diagnosis, management, and follow-up study of neonatal intracranial hemorrhage, and correlates well with the clinical findings.
The effect of cold-induced brain edema on cerebrospinal fluid formation rate
Authors: Go K. Gwan , Hochwald Gerald M. , Koster-Otte Lenie , van Zanten Annie K. , Gandhi Mysore
Published: May 2009

✓ The net contribution of vasogenic brain edema to cerebrospinal fluid (CSF) formation was studied by ventriculocisternal perfusion. Individual cats were perfused both before and 2 ½ hours after a severe cold-induced injury to the cerebral cortex, and the results were compared. Although the edema had occupied the larger part of the hemispheric white matter and bordered the lateral ventricle, a decrease rather than an increase in CSF formation rate was observed. This decrease was related to a decrease in the cerebral perfusion pressure by a regression equation that was not affected by the cold injury.
Alterations in ventricular size and intracranial pressure caused by sagittal sinus pathology in man
Authors: d'Avella Domenico , Greenberg Richard P. , Mingrino Salvatore , Scanarini Massimo , Pardatscher Kurt
Published: May 2009

✓ Lumbar cerebrospinal fluid (CSF) pressure and ventricular size were determined in six patients with impairment of cerebral venous outflow caused by either sagittal sinus thrombosis or arteriovenous shunting into the sagittal sinus. None of the patients had enlargement of the ventricular system, but all six had elevated CSF pressure (mean, 30 mm Hg). At least two mechanisms sufficient to prevent ventricular enlargement and significant hydrocephalus are suggested by these cases: 1) intracranial pressure elevations that occur as a result of cerebral venous outflow impediment maintain a positive pressure gradient between the intracranial CSF and the sagittal sinus contents, thereby increasing bulk CSF outflow; 2) in adults, increased function of alternative CSF outflow pathways occurs secondary to sagittal sinus thrombosis across the arachnoid villi of other intracranial vascular structures and in the spine. These mechanisms may have general importance in the generation of hydrocephalus caused by other disease states in adults but not in children.
Myoglobinuria following epsilon-aminocaproic acid (EACA) therapy
Authors: Brodkin Henry M.
Published: May 2009

✓ Myoglobinuria developed in a patient with subarachnoid hemorrhage treated with a course of 1.43 kg of epsilon-aminocaproic acid (EACA) given over 41 days. Review of eight other cases with a variety of medical disorders shows that this effect occurs after at least 4 weeks of taking doses of a minimum of 24 gm EACA per day. The effect seems to be reversible if discovered early. This side-effect should provide impetus for restricting the duration of EACA therapy to periods under 28 days, in doses no higher than 24 gm/day.
Dissecting aneurysm of the cerebral arteries
Authors: Grosman Harvey , Fornasier Victor L. , Bonder David , Livingston Kenneth E. , Platts Marjorie E.
Published: May 2009

✓ A spontaneous dissecting aneurysm of the left middle cerebral artery with extension into its major branches is reported in a 23-year-old man. The characteristic pathological and angiographic findings are demonstrated, including the rarely documented progression of this lesion. The etiological factors, the early recognition by the neuroradiologist, and the possibility of immediate treatment are briefly discussed in this report.
Computerized tomography findings in dural arteriovenous malformations
Authors: Miyasaka Kazuo , Takei Hidetoshi , Nomura Mikio , Sugimoto Sinji , Aida Toshimitsu , Abe Hiroshi , Tsuru Mitsuo
Published: May 2009

✓ Changes in the brain parenchyma and cerebrospinal fluid spaces were demonstrated in three cases of dural arteriovenous malformations by computerized tomography (CT). In various combinations, there were 1) vermiform or patchy enhancement after intravenous contrast infusion, 2) abnormal decreased density mainly in the white matter, 3) local mass effect, 4) hydrocephalus, 5) dilatation of the major venous sinus system, and 6) prominent vascular grooving of the skull inner table. Most of these changes were secondary to raised sinus pressure caused by arteriovenous shunt. It was also demonstrated by serial CT that some elements improved after artificial embolization or surgical excision of the malformations.
Giant arteriovenous fistula of the vein of Galen in early infancy treated successfully with surgery
Authors: Alvarez-Garijo Jose Andres , Mengual Manuel Vila , Gomila Dario Taboada , Martin Adela Alonso
Published: May 2009

✓ A giant arteriovenous fistula in a newborn infant was treated by surgical occlusion of the feeding vessels at 20 days of life. Congestive heart failure responded favorably to operative treatment. Because of persistent hydrocephalus, a shunt was inserted at 2 months of age. At 9 months of age, the child remained without signs of cardiac failure. Cerebral damage was manifested by a mild left hemiparesis. Successful surgical treatment of this unusual lesion in a neonate is exceptional.
Benign osteoblastoma of a thoracic vertebra
Authors: Epstein Nancy , Benjamin Vallo , Pinto Richard , Budzilovich Gleb
Published: May 2009

✓ A patient with osteoblastoma of the T-11 vertebral body presented with symptoms of spinal cord compression. Six weeks after an emergency laminectomy and subtotal removal, spinal computerized tomography disclosed residual tumor, which was totally removed via a combined anterior transthoracic approach and posterior laminectomy.
Primary reticulum-cell sarcoma (microglioma) of the brain with massive cardiac metastasis
Authors: Benjamin Ivy , Case Mary E. S.
Published: May 2009

✓ A patient is presented with reticulum-cell sarcoma of the brain and a large metastasis to the heart.
Diastematomyelia associated with teratomas
Authors: Ugarte Nancy , Gonzalez-Crussi F. , Sotelo-Avila C.
Published: May 2009

✓ Diastematomyelia, a complete or incomplete sagittal division of the neural axis into halves, is usually accompanied by a number of other malformations. However, true teratomas arising in dorsal juxtaposition to the spinal axis and associated with diastematomyelia are extremely rare. In this paper, two infants with this neoplastic-malformative complex are discussed. The two most prevalent hypotheses in the pathogenesis of diastematomyelia are reviewed. The hypothesis of a persistent neurenteric canal continues to be generally accepted, but, until more is known about the pathogenesis of extragonadal human teratomas, it is not possible to say how these neoplasms relate to the associated spinal cord malformation. Individually, each of the lesions present is extremely rare; it is possible that their concurrence in two patients may not be purely coincidental.
Treatment of spinal epidural metastases
Authors: Young Ronald F. , Post Elisabeth M. , King Gerald A.
Published: May 2009

✓ Metastases to the spinal epidural space with compression of the spinal cord or cauda equina are commonly encountered by physicians in a variety of clinical fields. In the recent past, decompressive laminectomy followed by radiotherapy was thought to be the best available treatment. More recently, radiotherapy alone has been advocated as an alternative treatment mode with a similar rate of effectiveness. This study compares laminectomy followed by radiotherapy to radiotherapy alone in the treatment of spinal epidural metastases in a randomized, prospective clinical trial. No significant difference was found in the effectiveness of the two treatment methods in regard to pain relief, improved ambulation, or improved sphincter function. Patients with an incomplete myelographic block fared well regardless of treatment, and those with a complete block fared poorly. Because of the limited size of this study and because of certain unforeseen design defects, the results are suggestive but not conclusive. Suggestions are made for a future randomized, prospective multicenter study that would conclusively answer the perplexing question as to the most efficacious method for treating spinal epidural metastases.
The effect of spinal distraction on regional spinal cord blood flow in cats
Authors: Dolan Eugen J. , Transfeldt Ensor E. , Tator Charles H. , Simmons Edward H. , Hughes Kenneth F.
Published: May 2009

✓ Distraction is considered to be a factor in many spinal cord injuries. With a specially designed distraction apparatus and the 14C-antipyrine autoradiographic technique, the effect of distraction on spinal cord blood flow (SCBF) in cats was studied. Distraction was performed at L2–3 at a rate of 0.25 cm/10 min, and the spinal evoked response (SER) was monitored by stimulating the sciatic nerve and recording at T-13. The SCBF was assessed in five control animals, four animals in whom the SER was markedly altered by distraction, and five animals after the SER had been abolished and an additional 0.5 cm distraction applied. Control cats had gray- and white-matter flows of 44.5 ± 1.4 (SEM) and 10.5 ± 0.4 ml/100 gm/min, respectively. Distraction to the point of marked SER alteration caused a 50% loss of SCBF at and caudal to the distraction site. An additional 0.5 cm distraction produced total abolition of SCBF at the distraction site and for a considerable distance rostral and caudal to it. Thus, it is shown that spinal distraction causes cord ischemia similar to that seen with other types of spinal cord injury. In addition, distraction severe enough to cause loss of the SER has already produced severe cord ischemia.
Carotid thromboendarterectomy: a reappraisal
Authors: Hugenholtz Herman , Elgie Robert G.
Published: May 2009

✓ Thromboendarterectomy performed in 35 patients with symptoms distal and ipsilateral to an occluded internal carotid artery resulted in patency in 19 cases (53%). Two factors that influence successful operation are early intervention following occlusion and good collateral circulation. In only 12 patients (34%) could the interval from occlusion to surgery be confidently determined. Four of these vessels, occluded for up to 7 days (100%), and five of eight vessels (63%), occluded for up to 4 weeks, were reopened. In the remaining patients, where the duration of occlusion was indefinite, greater reliance was placed on the evaluation and grading of angiographic collateral supply distal to the occlusion. Patients with Grade 1 to 3 collateral supply should not be explored unless occlusion occurred very recently. Patients with Grades 4 and 5 collateral supply are considered for carotid exploration regardless of the duration of the occlusion, as an alternative to other methods of revascularization.
Cerebral vasospasm: contractile activity of hemoglobin in isolated canine basilar arteries
Authors: Tanishima Takeo
Published: May 2009

✓ Recent studies suggest the possible role of the red blood cell (RBC) in causing chronic cerebral vasospasm. However, the basic action of hemoglobin (Hb), the major component of the RBC, on cerebral arteries remains unknown. The present study was undertaken to analyze the contractile effects of human Hb (purified by ion-exchange chromatography) on canine arteries in vitro. The contractile activity of lysed RBC was shown to be derived from Hb. Hemoglobin in oxygenated form (oxyHb) caused a maximum contraction equal to about 70% of that induced by serotonin in the basilar artery. Ferrous Hb's (oxyHb and carboxyHb) produced much greater contraction than ferric Hb's (methemoglobin and cyanmethemoglobin), suggesting that superoxide radicals, an active species of oxygen, may be related to the contractile activity of Hb. Neither methysergide, phentolamine, mepyramine, nor aspirin inhibited the vasoconstrictive activity of oxyHb. This finding indicates that the activation of serotonergic, alpha-adrenergic, or histaminergic H1 receptors, or prostaglandin synthesis may not be involved in the mechanism of action of oxyHb. The constituents of Hb caused little or no contraction as compared with Hb as a whole. The basilar artery was more highly sensitive to Hb than arteries from other anatomical locations. Cyclic adenosine monophosphate caused a very slight decrease in the Hb-induced contraction. It is concluded that oxyHb can contract cerebral arteries in vitro. These results, coupled with recent reports on the participation of the RBC in producing chronic vasospasm, strongly suggest that oxyHb released from RBC's plays an important role in the pathogenesis of chronic cerebral vasospasm.
The effects of mechanical immobilization on sutural development in the growing rabbit
Authors: Foley William J. , Kokich Vincent G.
Published: May 2009

✓ Methyl-2-cyanoacrylate was used to mechanically immobilize the coronal suture unilaterally in a series of New Zealand white rabbits at varying ages. The animals were separated into groups; some were sacrificed at 30 days and some at 60 days postoperatively. Amalgam markers were placed in the parietal and frontal bones across the coronal suture, and were measured immediately after surgery and at the time of sacrifice to confirm mechanical immobility. The animals were studied radiographically and histologically in order to document the presence or absence of sutural bone union. Based on the results of this study, it appears that immobilization of the coronal suture results in the formation of an ectocranial periosteal bone bridge in rabbits less than 8 weeks of age. Bone union was not found in animals older than 8 weeks of age. This age-related difference in response is believed to be due to decreased periosteal depository activity on the ectocranial surface of the calvaria once the brain ceases to expand actively. Furthermore, bone union or synostosis was never seen within or across the internal portion of the sutural ligament. It is suggested, therefore, that sutural immobilization at young ages in the rabbit does not result in sutural synostosis and that the term “periosteal bone bridge” should be used when referring to this biological response.
The evolving role of the nurse practitioner in neurosurgery
Authors: Rimel Rebecca W. , Langfitt Thomas W.
Published: May 2009

✓ The authors examine the many important roles for the nurse practitioner in neurosurgery, including patient care in academic departments and private practice, and research and scholarship. The responsibilities of nurse practitioners in a hospital can be varied: they may take some responsibility for all patients on the neurosurgery service, or their assignment may be more specific, such as to the intensive care unit; or they may be assigned to all patients with a specified neurosurgical disorder, such as head injury or intractable pain. Nurse practitioners can become coordinators of clinical research programs, with responsibility for collecting and collating the data and assisting in data analysis and manuscript preparation. Detailed clinical protocols must be developed for nurse practitioners, and those protocols then become the basis for their employment and legal status. Licensure requirements vary greatly among states, and are continuing to change.
An improved rat brain-tumor model
Authors: Kobayashi Naoki , Allen Norman , Clendenon Nancy R. , Ko Li-Wen
Published: May 2009

✓ The widely used intracerebral tumor implantation method by freehand injection into parietal or hippocampal areas of the rat brain has proven inadequate for reliable experimental therapeutic studies. Problems include poor intracerebral growth yields and significant rates of spread to extracranial tissues, lungs, and spinal cord. Major variables have been examined experimentally on a model using nitrosourea-induced nervous system tumor cell lines in syngeneic rats. A rapid stereotaxic method greatly improved the consistency of tumor placement. The optimal site was found to be the caudate nucleus. The production of a spheroid intracerebral growth was further facilitated by the use of 1% agar in the cell suspension medium and by an injection volume of 10 µl containing at least 104 cells. Further improvements involved injection technique and flushing of the operative field.

These modifications have resulted in a 99% to 100% yield of intracerebral growth, with a marked reduction in the number and size of extracranial extensions and with distant metastasis rates of 0% to 5%. These results have continually improved with further experience. The method is satisfactory for radiation and chemotherapeutic trials in which survival time as an index of tumor size may be used as an end point.
Computerized three-dimensional stereotaxic removal of small central nervous system lesions in patients
Authors: Jacques Skip , Shelden C. Hunter , McCann Gilbert D. , Freshwater Donald B. , Rand Robert
Published: May 2009

✓ The authors describe the results of their recently reported computer-based stereotaxic surgical technique for the identification, enhancement, three-dimensional reconstruction, localization, and removal of small central nervous system lesions. This technique has been applied to patients with various types of central nervous system pathology, and representative cases are reported.
Cysts in malignant gliomas
Authors: Afra Denes , Norman David , Levin Victor A.
Published: May 2009

✓ The clinical course, computerized tomography (CT) scans, and postmortem reports for 265 patients treated for malignant brain tumors were reviewed. Forty-one patients underwent reoperation for tumor recurrence and one had needle aspiration as a diagnostic procedure; of these patients, seven (3% of 265 and 17% of 42) were diagnosed as harboring tumor cysts and 10 (25% of 41) as having necrotic tumor centers. The CT scans on the 17 patients harboring tumors with surgically confirmed cysts and necrotic centers were reviewed; criteria for distinguishing between cysts and central necrosis are suggested. The relative benefits of repeated aspiration and surgical therapy for these cystic lesions are discussed.
Odontoid compression of the brain stem in a patient with rheumatoid arthritis
Authors: Smith Harold P. , Challa Venkata R. , Alexander Eben
Published: May 2009

✓ Cervical spine involvement by rheumatoid arthritis is common; brain-stem compression secondary to vertical subluxation of the odontoid in patients with rheumatoid arthritis is rare. Vertical subluxation results from 1) destruction of the transverse atlantal, apical, and alar ligaments of the atlas and odontoid, and 2) bone resorption in the occipital condyles, lateral masses of the atlas, and basilar processes of the skull. Neurological symptoms result from direct compression of the brain stem or from ischemia secondary to compression of vertebral arteries, anterior spinal arteries, or small perforating arteries of the brain stem and spinal cord. A case is reported in which a slowly progressive neurological deficit developed in a woman with rheumatoid arthritis following a fall from a stretcher. Neurological symptoms represented direct compression of the medulla by the dens, a mechanism confirmed at operation and autopsy.

Recognition of progressive neurological deficit is often difficult in patients with rheumatoid arthritis because of their inactivity and their atrophic and immobile joints, but is essential if appropriate decompressive or stabilizing procedures are to be done. In patients with vertical subluxation of the dens, the transoral approach with removal of the odontoid is recommended. Decompression should be extensive, including the fibrous capsule around the odontoid and overlying synovial tissue as well as the odontoid itself.
Angiographically cryptic AVM presenting as a pontine tumor
Authors: Albright A. Leland , Byrd Ryland P. , Harrison Mary Lee
Published: May 2009

✓ A 19-month-old child became disoriented and ataxic 6 days after a diphtheria-pertussis-tetanus (DPT) booster injection. Computerized tomographic scan revealed a hyperdense mesencephalic-pontine mass, and angiography demonstrated an avascular mass. Pontine biopsy revealed no abnormality. Her clinical course fluctuated until her death 15 months later. At autopsy, an angiographically cryptic arteriovenous malformation (AVM) was present in the mesencephalon and pons. Vascular malformations of the brain stem, producing prolonged clinical courses, are reviewed.
Spontaneous opening of large occipital-vertebral artery anastomosis during embolization
Authors: Spetzler Robert F. , Modic Michael , Bonstelle Charles
Published: May 2009

✓ A patient undergoing external carotid artery therapeutic embolization for obliteration of a dural arteriovenous malformation suddenly developed a large occipital artery to vertebral artery shunt. A devastating stroke was averted because the appearance of the shunt was observed by fluoroscopy, the embolization was stopped, and the shunt verified on a subsequent angiogram. The risk of external carotid artery embolization without constant fluoroscopic control is emphasized.
Brachial plexus injury following axillary arteriography
Authors: O'Keefe Dennis M.
Published: May 2009

✓ A case of brachial plexus injury following axillary arteriography is reported. Electrodiagnostic studies localized the lesion to the region of the puncture site. Review of the literature indicates that neural injury is due to a localized hematoma or pseudoaneurysm at the site of arterial puncture. Surgical decompression of the brachial plexus within 24 hours of the onset of motor dysfunction results in a much improved prognosis. Clinical findings that help to differentiate between postoperative traction injury and brachial plexus injury following axillary arteriography are discussed.
Inside—outside technique for posterior occipitocervical spine instrumentation and stabilization: preliminary results
Authors: Pait T. Glenn , Al-Mefty Ossama , Boop Frederick A. , Arnautovic Kenan I. , Rahman Salim , Ceola Wade
Published: May 2009

Object. The authors present a series of 16 patients who underwent inside—outside occipital and posterior cervical spine stabilization.

Methods. In this technique, the screw was placed from the inside of the occiput to the outside. An articular (lateral) mass plate was contoured to the shape of the occipital bone and the cervical spine and affixed to the occiput with a flat-headed screw or stud placed through a burr hole in the calvaria with the flat head of the screw in the epidural space and the threads facing outward. The bone plate was then secured with a nut to the occipital screw and the cervical plate was attached to the spine with a bone screw that coursed through the plate and into the articular pillar. Our series included six children and 10 adults. In five patients, previous fusion had failed; in two patients spinal instability was secondary to Down's syndrome; two patients' instability was related to developmental anomalies; and in five patients spinal instability was due to the presence of tumor. One patient with rheumatoid arthritis had undergone a transoral procedure. Two patients had suffered traumatic fracture. Three patients died of causes unrelated to the procedure, one patient died of metastatic cancer, and one patient died in a long term care facility of cardiopulmonary complications. One patient with renal failure suffered a hemorrhage from an arteriovenous fistula after being treated with dialysis. In one child, a nut backed off after 3 months. The nut was reseated, and a maturing arthrodesis was present.

Conclusions. The authors conclude that the inside—outside occipitocervical fixation is an effective technique for stabilizing the cervical spine.
Anterior cervical discectomy: is fusion necessary?
Authors: Dowd Gregory C. , Wirth Fremont P.
Published: May 2009

Object. A prospective, randomized trial was performed to compare the efficacy of anterior cervical discectomy (ACD) with ACD and fusion (ACDF) for the treatment of cervical spondylosis in patients with neurological compromise.

Methods. Forty-four patients underwent ACD and 40 underwent ACDF. Operative time and length of hospital stay were shorter and there was less need for analgesia in the ACD group. It was found that whereas the incidence of fusion was greater in the ACDF group compared to the ACD group (97 compared with 70%, respectively; p < 0.01), patient satisfaction and a return to preoperative activity level was similar between groups.

Conclusions. Analysis of the results suggests that the addition of a fusion procedure may be unnecessary.
Risk of early closed reduction in cervical spine subluxation injuries
Authors: Grant Gerald A. , Mirza Sohail K. , Chapman Jens R. , Winn H. Richard , Newell David W. , Jones Dolors T. , Grady M. Sean
Published: May 2009

Object. The authors retrospectively reviewed 121 patients with traumatic cervical spine injuries to determine the risk of neurological deterioration following early closed reduction.

Methods. After excluding minor fractures and injuries without subluxation, the medical records and imaging studies (computerized tomography and magnetic resonance [MR] images) of 82 patients with bilateral and unilateral locked facet dislocations, burst fractures, extension injuries, or miscellaneous cervical fractures with subluxation were reviewed. Disc injury was defined on MR imaging as the presence of herniation or disruption: a herniation was described as deforming the thecal sac or nerve roots, and a disruption was defined as a disc with high T2-weighted signal characteristics in a widened disc space. Fifty-eight percent of patients presented with complete or incomplete spinal cord injuries. Thirteen percent of patients presented with a cervical radiculopathy, 22% were intact, and 9% had only transient neurological deficits in the field.

Early, rapid closed reduction, using serial plain radiographs or fluoroscopy and Gardner—Wells craniocervical traction, was achieved in 97.6% of patients. In two patients (2.4%) closed reduction failed and they underwent emergency open surgical reduction. The average time to achieve closed reduction was 2.1 ± 0.24 hours (standard error of the mean).

The incidence of disc herniation and disruption in the 80 patients who underwent postreduction MR imaging was 22% and 24%, respectively. However, the presence of disc herniation or disruption did not affect the degree of neurological recovery, as measured by American Spinal Injury Association motor score and the Frankel scale following early closed reduction. Only one (1.3%) of 80 patients deteriorated, but that occurred more than 6 hours following closed reduction.

Conclusions. Although disc herniation and disruption can occur following all types of traumatic cervical fracture subluxations, the incidence of neurological deterioration following closed reduction in these patients is rare. The authors recommend early closed reduction in patients presenting with significant motor deficits without prior MR imaging.
Anterior cervical plating for the treatment of neoplasms in the cervical vertebrae
Authors: Caspar Wolfhard , Pitzen Tobias , Papavero Luca , Geisler Fred H. , Johnson Todd A.
Published: May 2009

Object. To assess clinical outcome and survival in patients with cervical vertebral spinal neoplasms after they have undergone anterior decompression and cervical plate stabilization (ACPS) by using either autologous bone graft or polymethylmethacrylate (PMMA) as the anterior load-bearing support structure.

Methods. This was a retrospective case study composed of 30 patients harboring cervical spinal vertebral neoplasms who underwent anterior cervical decompression and (ACPS) within a 7-year period. Postoperative immobilization included treatment in a halo brace in two cases and in a hard cervical collar for the remaining patients. Postoperatively most patients underwent radio- and/or chemotherapy. All patients except one benefited from a significantly improved quality of life with decreased pain and/or improved neurological status. The mean Kaplan—Meier survivoral estimate was 35.8 months (range 8 days–11.3 years, with 10 patients alive at most recent follow-up contact). Patients achieved long-term or lifelong mechanical stability in the cervical spine, and only one patient required a repeated posterior stabilization procedure. No hardware-related complications occurred. One patient died 8 days postoperatively of pneumonia. A nonsignificant difference in survival (p = 0.2164) was observed between patients harboring metastatic neoplasms (26.8 months) and those harboring lymphomatous and multiple myeloma neoplasms (54 months).

Conclusions. Favorable clinical outcome of both neurological symptoms and pain can be achieved using ACPS after surgery for neoplasms in the cervical vertebrae. Furthermore, long-term or lifelong cervical spine mechanical stability with bone fusion is achieved using this technique even when radiation therapy is delivered to the site of the bone graft.
Cervical corpectomy: report of 185 cases and review of the literature
Authors: Eleraky Mohammed A. , Llanos Carlos , Sonntag Volker K. H.
Published: May 2009

Object. This study was conducted to determine the indications, safety, efficacy, and complication rate associated with performing corpectomy to achieve anterior decompression of neural elements or for removing anterior lesions.

Methods. Between 1987 and 1998, 185 patients underwent cervical corpectomy for the treatment of degenerative spondylitic disease (81 cases), ossification of posterior longitudinal ligament (16 cases), correction of postoperative kyphosis (31 cases), trauma (39 cases), tumor (10 cases), and infection (eight cases). Ninety-nine patients presented with myelopathy, 48 with radiculomyelopathy, 24 with radicular pain, and 14 with neck muscle pain. Eighty-seven patients underwent a one-level corpectomy; 45 of these patients underwent a discectomy at a different level. Seventy patients underwent a two-level corpectomy; 27 of these patients underwent a discectomy at a different level. Twenty-eight patients underwent a three-level corpectomy. Autograft (iliac crest) was used in 141 cases and allograft (fibula) in 44 cases. All but six patients underwent fixation with an anterior plate-screw system. There were no operative deaths. During the procedure the vertebral artery was injured in four patients and preserved in two of them. No neurological sequelae were encountered. Postoperative hoarseness, transient dysphagia, and pain at the graft site were transitory and successfully managed. The fusion rate was 98.8%. Six patients experienced transient deterioration after surgery but they improved. No patient experienced permanent neurological deterioration and 160 (86.5%) improved.

Conclusions. Corpectomy has an important role in the management of various degenerative, traumatic, neoplastic, or infectious disorders of cervical spine. Following treatment in this series, radiculopathy always improved and myelopathy was reversed in most patients.
Palliative subtotal vertebrectomy with anterior and posterior reconstruction via a single posterior approach
Authors: Cahill David W. , Kumar Rakesh
Published: May 2009

Object. Laminectomy for the treatment of spinal metastatic disease is ineffective. Total spondylectomy requiring both anterior and posterior operations may cause undue morbidity in patients with a limited life expectancy. The authors demonstrate the technique, feasibility, and success of subtotal vertebrectomy that is followed by anterior and posterior reconstruction via a simple posterior approach. Although this remains a palliative procedure, it provides circumferential decompression and spinal stabilization by using rigid hardware.

Methods. The authors present a review of nine of 43 consecutive patients with spinal metastatic disease who underwent operation in a 42-month period. Via a single midline posterior approach, the authors performed single-stage circumferential decompression of the theca followed by anterior and posterior reconstruction. Anterior support is provided by a methylmethacrylate reconstruction retained with Steinmann pins. Posterior reconstruction is achieved by placement of rigid hook or pedicle screw and rod instrumentation.

Eight of the nine patients died of progression of underlying disease. All patients remained pain free until days before they died. Except for a patient with paraplegia who did not recover, all other patients remained ambulatory. Despite radio-, chemo-, and steroid therapy, there were no wound infections or breakdowns. One patient underwent reoperation because of a technical error.

Conclusions. Use of the near-total vertebrectomy followed by anterior and posterior reconstruction from T2 to L3 by using a single midline posterior approach spares the patient, who has a limited life expectancy, the operative risks associated with thoracotomy or thoracoabdominal approaches. The authors restrict the procedure for use in patients with extensive bony disease, noncontiguous spinal involvement, visceral metastases, other contraindications to a transcavitary procedure, and those with advanced age.
Intraoperative spinal angiography
Authors: Schievink Wouter I. , Vishteh A. Giancarlo , McDougall Cameron G. , Spetzler Robert F.
Published: May 2009

Object. The use of intraoperative angiography of the spine has become available to neurosurgeons as an adjunct in the management of complex spinal vascular malformations. These vascular malformations are rare, and the use of intraoperative angiography of the spine has not been well described. The authors report their recent experience with the use of this diagnostic modality.

Methods. Between 1995 and 1997, nine consecutive patients with type II or Type IV spinal arteriovenous malformations (AVMs) underwent intraoperative spinal angiography. The cervical spine was involved in three patients, the thoracic spine in five, and the thoracolumbar junction in one. In three patients, intraoperative spinal angiography revealed an unexpected finding (residual filling of the AVM). The results obtained using postoperative spinal angiography in all patients showed complete agreement with the intraoperative studies. No complications arose from obtaining the intraoperative spinal angiograms.

Conclusions. Intraoperative spinal angiography is technically feasible, can be performed safely, and has adequate resolution. It detects unexpected residual AVM in one-third of cases.