bluuebunny/crossref_metadata_2025 huggingface dataset:
The long-term outcome after surgical treatment of dorsally exophytic brain-stem gliomas
Authors: Pollack Ian F. , Hoffman Harold J. , Humphreys Robin P. , Becker Larry
Published: May 2009

✓ Dorsally exophytic brain-stem gliomas represent a distinctive subgroup of pediatric brain-stem neoplasms that are amenable to radical excision because of their benign histology and growth characteristics. However, their attachment to the floor of the fourth ventricle invariably precludes complete tumor excision. The long-term behavior of the residual tumor remains a subject of concern. To address this issue, the authors reviewed their experience with 18 dorsally exophytic brain-stem gliomas treated between 1974 and 1990. At operation, the tumors filled the fourth ventricle, fungating out of a broad-based area of the dorsal brain stem. The exophytic tumor was resected, but no attempt was made to remove tumor from the brain stem. Histological examination showed that 16 of the tumors were grade I or II astrocytomas, one was a ganglioglioma, and one was an otherwise benign-appearing glioma with several foci of anaplasia that was classified as a grade III astrocytoma. The latter patient was one of only two in the series to receive postoperative radiation therapy; both cases so treated have no evidence of disease on follow-up imaging studies 61 and 135 months postoperatively. One other child who had stable disease postoperatively died of shunt malfunction 18 months after tumor excision. Serial radiographic studies in the other 15 patients have shown no evidence of disease in three, stable residual disease in eight, and tumor enlargement 12, 28, 40, and 84 months postoperatively in four (median follow-up period 113 months). Each of the four patients with tumor regrowth underwent repeat tumor excision. Two of these children received perioperative radiation therapy at the time of disease progression and both showed reduction in tumor volume 28 and 65 months after their second operation. In contrast, both patients who did not receive radiotherapy at the time of disease progression had further tumor enlargement 48 and 84 months after their second operation and underwent a third tumor resection; one received postoperative radiation therapy and has no evidence of disease 58 months after his third operation and the other child has stable disease 27 months postoperatively. Histological examination of tumor specimens obtained at second and third operations showed no change from the appearance of the tumor on the initial resection. The authors conclude that the majority of dorsally exophytic brain-stem gliomas can be managed successfully with subtotal excision and, if necessary, cerebrospinal fluid diversion. The small percentage of tumors in this series that showed recurrent growth remained benign histologically. In these patients, repeat tumor resection and radiotherapy appeared to be effective in maintaining long-term disease control.
Neurological complications of ankylosing spondylitis
Authors: Fox Mark W. , Onofrio Burton M. , Kilgore John E.
Published: May 2009

✓ Thirty-three patients with ankylosing spondylitis with or without spinal neurological symptoms requiring surgical intervention were identified in a retrospective review of all cases of spinal disorders treated at the Mayo Clinic during the period from 1984 to 1989. Spinal fractures (traumatic or pseudoarthroses), progressive spinal deformity, rotary instability secondary to atlanto-occipital or atlantoaxial subluxation, and spinal stenosis with associated neurological deficit, pain, or spinal instability were the most common indications for surgery. Of the 41 operations performed, there were 17 cervical, 14 thoracic, and 10 lumbar procedures. Eight patients had two or more disorders at separate spinal levels that required surgery. Preoperative neurological deficits were recorded in 13 patients: these improved following surgery in nine and stabilized in four.

This review emphasizes the fragility of the ankylosed spinal column and its inherent susceptibility to fracture with attendant neurological compromise. It also identifies the variety of spinal disorders observed in these patients and discusses their surgical management. The experience with this series suggests that thorough radiological evaluation, extreme caution with endotracheal intubation and with halo-vest applications, early surgical spinal immobilization, and aggressive postoperative mobilization of patients are necessary for a successful outcome. It is concluded that outcomes in these patients can be favorable when managed appropriately.
A randomized trial of radiotherapy versus radiotherapy plus CCNU for incompletely resected low-grade gliomas: a Southwest Oncology Group study
Authors: Eyre Harmon J. , Crowley John J. , Townsend Jeannette J. , Eltringham James R. , Morantz Robert A. , Schulman Susan F. , Quagliana Joseph M. , Al-Sarraf Muhyi
Published: May 2009

✓ Sixty adult patients with incompletely excised low-grade gliomas were randomly assigned to receive radiotherapy (55 Gy over a total of 6½ to 7 weeks) either alone or with 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU; 100 mg/sq m every 6 weeks). Pathological review showed that six patients were ineligible for the study. Evaluation of patient age. extent of surgery, tumor grade, and performance status showed no significant differences between the treatment arms. The response rate, as judged by the disappearance or reduction in size of the tumor on computerized tomography scans, was 79% for radiation therapy alone versus 54% for irradiation plus CCNU. The median survival time was 4.45 years for all patients, with no significant difference between treatment arms (p = 0.7). For the group as a whole, patient age and performance status were the most important prognostic parameters. The majority of patients receiving chemotherapy experienced moderate hematological toxicity. This study demonstrates that CCNU chemotherapy does not improve the results of radiation therapy in the treatment of incompletely excised low-grade gliomas.
Systemic T-cell lymphoma presenting with isolated neurological dysfunction and intraparenchymal brain lesions
Authors: Herman Martin D. , Gordon Leo I. , Kaul Karen , Variakojis Diana , Bauer Ken , Levy Robert M.
Published: May 2009

✓ Secondary non-Hodgkin's lymphoma of the central nervous system is typically a late manifestation of systemic T-cell lymphoma, with a 2-month median survival time after the development of neurological disease. Of the reported patients with this late complication, only 1% manifest spread of the disease to the brain parenchyma. The authors report a patient with an unusual initial neurological presentation of systemic T-cell lymphoproliferative disorder and associated space-occupying lesions of the brain parenchyma. The diagnosis was supported by extensive molecular, immunological, and histopathological analysis. Neurological symptoms appeared early in the course of systemic disease and were characterized by spontaneous exacerbations and remissions. The patient has survived for more than 5 years since the onset of his neurological symptoms. Histopathological characterization including immunoperoxidase staining for T-cell markers, DNA content, and cell-cycle analysis of brain tissue obtained at stereotactic biopsy were compared to those of atypical lymphoid cells of peripheral blood, bone marrow, and liver. The neurological manifestations and possible etiologies of T-cell lymphoma are discussed.
Ultrasound-controlled neuronavigator-guided brain surgery
Authors: Koivukangas John , Louhisalmi Yrjö , Alakuijala Jyrki , Oikarinen Jarkko
Published: May 2009

✓ The development of a unique neurosurgical navigator is described and a preliminary series of seven cases of intracerebral lesions approached with the assistance of this neuronavigation system under ultrasound control is presented. The clinical series included five low-grade astrocytomas, one chronic intracerebral hematoma, and one porencephalic cyst. Management procedures included biopsy in all cases, drainage of the hematoma, and endoscopy and fenestration for the cyst. The features of the neuronavigation system are interactive reconstructions of preoperative computerized tomography and magnetic resonance imaging data, corresponding intraoperative ultrasound images, versatility of the interchangeable end-effector instruments, graphic presentation of instruments on the reconstructed images, and voice control of the system. The principle of a common axis in the reconstructed images served to align the navigational pointer, biopsy guide, endoscope guide, ultrasound transducer, and surgical microscope to the brain anatomy. Intraoperative ultrasound imaging helped to verify the accuracy of the neuronavigator and check the results of the procedures. The arm of the neuronavigation system served as a holder for instruments, such as the biopsy guide, endoscope guide, and ultrasound transducer, in addition to functioning as a navigational pointer. Also, the surgical microscope was aligned with the neuronavigator for inspection and biopsy of the hematoma capsule to rule out tumor etiology. Voice control freed the neurosurgeon from manual exercises during start-up and calibration of the system.
Low-grade gliomas associated with intractable epilepsy: seizure outcome utilizing electrocorticography during tumor resection
Authors: Berger Mitchel S. , Ghatan Saadi , Haglund Michael M. , Dobbins Jill , Ojemann George A.
Published: May 2009

✓ Adults and children with low-grade gliomas often present with medically refractory epilepsy. Currently, controversy exists regarding the need for intraoperative electrocorticography (ECoG) to identify and, separately, resect seizure foci versus tumor removal alone to yield maximum seizure control in this patient population. Forty-five patients with low-grade gliomas and intractable epilepsy were retrospectively analyzed with respect to preoperative seizure frequency and duration, number of antiepileptic drugs, intraoperative ECoG data (single versus multiple foci), histology of resected seizure foci, and postoperative control of seizures with or without antiepileptic drugs.

Multiple versus single seizure foci were more likely to be associated with a longer preoperative duration of epilepsy. Of the 45 patients studied, 24 were no longer taking antiepileptic drugs and were seizure-free (mean follow-up interval 54 months). Seventeen patients, who all had complete control of their seizures, remained on antiepileptic drugs at lower doses (mean follow-up interval 44 months); seven of these patients were seizure-free postoperatively, yet the referring physician was reluctant to taper the antiepileptic drugs. Four patients continued to have seizures while receiving antiepileptic drugs, although at a reduced frequency and severity. In this series 41% of the adults versus 85% of the children were seizure-free while no longer receiving antiepileptic drugs, with mean postoperative follow-up periods of 50 and 56 months, respectively. This difference was statistically significant (p = 0.016). Therefore, based on this experience and in comparison with numerous retrospective studies involving similar patients, ECoG is advocated, especially in children and in any patient with a long-standing seizure disorder, to maximize seizure control while minimizing or abolishing the need for postoperative antiepileptic drugs.
Neurocognitive efficiency following left temporal lobectomy: standard versus limited resection
Authors: Wolf Ronald L. , Ivnik Robert J. , Hirschorn Kathryn A. , Sharbrough Frank W. , Cascino Gregory D. , Marsh W. Richard
Published: May 2009

✓ Decreased memory and learning efficiency may follow left temporal lobectomy. Debate exists as to whether the acquired deficit is related to the size of the surgical resection. This study addresses this question by comparing changes in cognitive performance to the extent of resection of both mesial temporal structures and lateral cortex.

The authors retrospectively reviewed 47 right-handed patients who underwent left temporal lobectomy for medically intractable seizures. To examine the effects of the extent of mesial resection, the patients were divided into two groups: those with resection at the anterior 1 to 2 cm of mesial structures versus those with resection greater than 2 cm. To examine the effects of the extent of lateral cortical resection, patients were again divided into two groups: those with lateral cortex resections of 4 cm or less versus those with resections greater than 4 cm.

Statistical analyses showed no difference in cognitive outcome between the groups defined by the extent of mesial resection. Likewise, no difference in cognitive outcome was seen between the groups defined by the extent of lateral cortical resection. Associated data analyses did, however, reveal a negative correlation of cognitive change with patient age at seizure onset. These results showed that the neurocognitive consequences of extended mesial resections were similar to those of limited mesial resections, and that the neurocognitive consequences of extended lateral cortical resections were similar to those of limited lateral cortical resections. The risk of cognitive impairment depends more on age at seizure onset than on the extent of mesial or lateral resection.
An experimental model of retrovirus gene therapy for malignant brain tumors
Authors: Takamiya Yoshiaki , Short M. Priscilla , Moolten Frederick L. , Fleet Christina , Mineta Toshihiro , Breakefield Xandra O. , Martuza Robert L.
Published: May 2009

✓ Recent research using rodent models of central nervous system gliomas indicates that a combination of gene transfer and drug treatment may be successful in killing tumor cells. In the present study, a mouse fibroblast-derived packaging cell line, psi 2, which releases a replication-defective retrovirus vector bearing the herpes simplex virus type 1 (HSV)-thymidine kinase (TK) gene, was grown with rat C6 tumor cells in the presence and absence of wild type Moloney murine leukemia virus (MoMLV). Consequently, tumor cells became sensitive to ganciclovir, which is selectively converted to a toxic nucleotide analog by HSV-TK. This killing effect was more effective in the presence than in the absence of wild type retrovirus both in culture and in subcutaneous tumors in nude mice. Tumors regressed in vivo and failed to regrow over a subsequent 10-day observation period after combined treatment with packaging cells, wild type MoMLV, and ganciclovir. This killing effect may be augmented by the ability of the helper retrovirus to package the vector in tumor cells and thus extend delivery of the HSV-TK gene to more tumor cells. This represents significant improvement in tumor therapy in this model system as compared with helper-free systems previously reported by the authors and others. Although additional improvements in the therapy can be envisioned, this approach may prove useful in combination with current modes of therapy for these insidious and lethal tumors.
Angiographic demonstration of a spinal epidural arteriovenous malformation
Authors: Olivero William C. , Hanigan William C. , McCluney Kerry W.
Published: May 2009

✓ A 16-year-old boy presented with acute midline thoracic pain followed by rapidly progressive paraplegia. The initial neurological examination demonstrated a complete sensory and motor paraplegia, which significantly improved spontaneously over the following 2 days. Magnetic resonance imaging revealed a posterior epidural hematoma extending from the T-4 to T-6 vertebrae, and spinal angiography demonstrated an arteriovenous malformation (AVM) with a nidus of abnormal epidural vessels at the level of the T-5 vertebra, which was confirmed surgically. This case represents one of the first reports of a spinal epidural AVM confirmed by angiography.
Spontaneous drainage of syringomyelia
Authors: Santoro Antonio , Delfini Roberto , Innocenzi Gualtiero , Di Biasi Claudio , Trasimeni Guido , Gualdi Gianfranco
Published: May 2009

✓ Two cases are reported of Arnold-Chiari type I malformation associated with syringomyelia, in which magnetic resonance (MR) imaging revealed spontaneous decompression of the syrinx. In one case axial MR imaging sections showed a communication between the syrinx and the spinal subarachnoid space, which supports the hypothesis that fissuring of the cord parenchyma is instrumental in the spontaneous resolution of syringomyelia. The MR imaging changes were not accompanied by variations in the patients' clinical course.
Development of neurosurgery in Southern California and the Los Angeles County/University of Southern California Medical Center
Authors: Schneider John H. , Weiss Martin H. , Couldwell William T.
Published: May 2009

✓ The Los Angeles County General Hospital has played an integral role in the development of medicine and neurosurgery in Southern California. From its fledgling beginnings, the University of Southern California School of Medicine has been closely affiliated with the hospital, providing the predominant source of clinicians to care for and to utilize as a teaching resource the immense and varied patient population it serves.
Natural history of unruptured intracranial aneurysms: a long-term follow-up study
Authors: Juvela Seppo , Porras Matti , Heiskanen Olli
Published: May 2009

✓ To investigate the natural history of unruptured aneurysms and predictive risk factors determining subsequent rupture, the authors followed 142 patients with 181 unruptured aneurysms until death or subarachnoid hemorrhage intervened, or for at least 10 years after the unruptured aneurysm was diagnosed. Six patients had a symptomatic aneurysm, five had an incidentally discovered aneurysm, and 131 had multiple aneurysms, of which the ruptured lesion was clipped at the beginning of the follow-up study. The median follow-up time was 13.9 years (range 0.8 to 30.0 years). During 1944 patient-years of follow-up study there were 27 first episodes of hemorrhage from a previously unruptured aneurysm, giving an average annual rupture incidence of 1.4%. Fourteen of these bleeding episodes were fatal. The cumulative rate of bleeding was 10% at 10 years, 26% at 20 years, and 32% at 30 years after the diagnosis.

The only predictor for the rupture was the size of the aneurysm (p = 0.036). However, in patients with multiple aneurysms (the main subgroup) the only variable that tended to predict rupture was the age of the patient: risk of rupture was inversely associated with age (p = 0.080). The median diameter of the aneurysms was 4 mm at the beginning of the follow-up period, both in those with and those without a later hemorrhage. During the angiographic monitoring period, a ruptured aneurysm significantly (p < 0.001) increased in size in 17 patients with hemorrhage but aneurysms did not increase significantly in 14 patients without hemorrhage. In addition, a new aneurysm was found in six of 31 patients. The authors conclude that an unruptured aneurysm should be operated on, irrespective of its size, if it is technically possible and the patient's age and concurrent diseases are not contraindications to surgery.
Cerebral revascularization using omental transplantation for childhood moyamoya disease
Authors: Karasawa Jun , Touho Hajime , Ohnishi Hideyuki , Miyamoto Susumu , Kikuchi Haruhiko
Published: May 2009

✓ Between January, 1986, and October, 1990, 30 children with moyamoya disease, aged from 2 to 17 years, underwent omental transplantation to either the anterior or the posterior cerebral artery territory. The mean follow-up period was 3.8 years, ranging from 1.6 to 6.4 years. Seventeen patients had symptoms of monoparesis, paraparesis, and/or urinary incontinence and were treated using unilateral or bilateral omental transplantation to the anterior cerebral artery territory. Eleven patients had visual symptoms and were treated with unilateral or bilateral omental transplantation to the posterior cerebral artery territory.

Two patients had symptoms associated with both the anterior and the posterior cerebral arteries, and were treated with dual omental transplantations. All 19 patients treated with omental transplantation to the anterior cerebral artery and 11 (84.6%) of the 13 treated with omental transplantation to the posterior cerebral artery showed improvement in their neurological state. Patients with more collateral vessels via the omentum had more rapid and complete improvement in their neurological state. Patients with severe preoperative neurological deficits associated with the posterior cerebral artery had persistence of their symptoms.
Adult intramedullary spinal cord ependymomas: the result of surgery in 38 patients
Authors: Epstein Fred J. , Farmer Jean-Pierre , Freed Diana
Published: May 2009

✓ Thirty-eight patients underwent surgery for an intramedullary spinal cord ependymoma. In 37 patients, postoperative magnetic resonance imaging confirmed that the tumor was totally removed. The morbidity of surgery was directly related to the preoperative neurological condition. Patients who were normal or nearly normal preoperatively were rarely worse after surgery, and those who had significant disability preoperatively were at greatest risk of being more impaired after surgery. There has been no tumor recurrence in any patient after a mean follow-up period of 24 months, and radiation therapy has not been employed as a surgical adjunct.
Surgical treatment of multiple brain metastases
Authors: Bindal Rajesh K. , Sawaya Raymond , Leavens Milam E. , Lee J. Jack
Published: May 2009

✓ The authors conducted a retrospective review of the charts of 56 patients who underwent resection for multiple brain metastases. Of these, 30 had one or more lesions left unresected (Group A) and 26 underwent resection of all lesions (Group B). Twenty-six other patients with a single metastasis who underwent resection (Group C) were selected to match Group B by type of primary tumor, time from first diagnosis of cancer to diagnosis of brain metastases, and presence or absence of systemic cancer at the time of surgery. Statistical analysis indicated that Groups A and B were also homogeneous for these prognostic indicators. Median survival duration was 6 months for Group A, 14 months for Group B, and 14 months for Group C. There was a statistically significant difference in survival time between Groups A and B (p = 0.003) and Groups A and C (p = 0.012) but not between Groups B and C (p > 0.5). Brain metastasis recurred in 31% of patients in Group B and in 35% of those in Group C; this difference was not significant (p > 0.5). Symptoms improved after surgery in 65% of patients in Group A, 83% in Group B, and 84% in Group C. Symptoms worsened in 13% of patients in Group A, 6% in Group B, and 0% in Group C. Groups A, B, and C had complication rates per craniotomy of 8%, 9%, and 8%, and 30-day mortality rates of 3%, 4%, and 0%, respectively. Guidelines for management of patients with multiple brain metastases are discussed. The authors conclude that surgical removal of all lesions in selected patients with multiple brain metastases results in significantly increased survival time and gives a prognosis similar to that of patients undergoing surgery for a single metastasis.
Intracranial parenchymal schwannoma
Authors: Casadei Gian Piero , Komori Takashi , Scheithauer Bernd W. , Miller Gary M. , Parisi Joseph E. , Kelly Patrick J.
Published: May 2009

✓ The clinical, radiological, and pathological features of nine cases of intracranial parenchymal schwannoma are described. The clinical course in four patients 23 years of age or younger mirrored the indolent nature of this neoplasm. Imaging studies included computerized tomography in eight patients and magnetic resonance imaging in three. The lesions were well demarcated with only mild surrounding edema. Five tumors were deep within the temporoparieto-occipital region, three were in the cerebellum, and one lay peripherally in the parietal lobe. Over two-thirds of the nine tumors were either cystic (five) or contained areas of cystic degeneration (two). One lesion was frankly hemorrhagic. A variety of imaging characteristics and contrast enhancement patterns were observed, including those of a cyst with a mural nodule and peripheral enhancement. Of the four solid neoplasms, two enhanced homogeneously while the other two demonstrated heterogeneous enhancement. Six tumors were resected totally. The follow-up period ranging from 2 months to 2 years has shown no recurrences. Microscopically, immunohistochemically, and ultrastructurally, the tumors were indistinguishable from peripheral schwannomas. A possible mechanism underlying the histogenesis of these rare lesions is discussed. The importance of recognizing this tumor is stressed, particularly in younger patients, given its benign nature, radiological resemblance to other tumors such as pilocytic astrocytoma, and favorable response to resection.
Carboplatin treatment of progressive optic pathway gliomas to delay radiotherapy
Authors: Moghrabi Albert , Friedman Henry S. , Burger Peter C. , Tien Robert , Oakes W. Jerry
Published: May 2009

✓ Six patients with optic pathway gliomas who were previously managed with surgery and/or chemotherapy were treated with carboplatin (560 mg/sq m) after radiographic evidence of disease progression. The median age at diagnosis was 2 years (range 4 months to 7 years), and the interval between diagnosis and carboplatin therapy ranged between 7 months and 6.5 years (median 1.8 years). Treatment was given at 4-week intervals and continued until unacceptable toxicity supervened, the disease progressed, or the disease was stable for 12 months. All patients demonstrated disease stability at the outset of the third cycle and continued to do so at the time of this writing. Two patients are 16 and 32 months from initial carboplatin therapy and have been off treatment for 5 and 14 months, respectively; two patients are still receiving therapy at 7 and 11 months after their initial treatment. During the study, two patients developed hypersensitivity to the drug, requiring its discontinuation. Toxicity was minimal, consisting mainly of thrombocytopenia, requiring a one-dose reduction in four of the six treated patients. No platelet transfusions were needed. These results suggest that carboplatin can arrest growth of progressive optic pathway gliomas in children and can allow delay of radiotherapy. A larger trial will be required to define the optimal use of carboplatin in the treatment of low-grade gliomas in children.
On-line monitoring of global cerebral hypoxia in acute brain injury
Authors: Cruz Julio
Published: May 2009

✓ Global cerebral oxygenation, perfusion pressure, and expired CO2 tension were continuously monitored in 69 adults with acute severe closed brain trauma. Cerebral oxygenation was assessed by continuous fiberoptic monitoring of jugular bulb oxyhemoglobin saturation, in conjunction with continuous monitoring of arterial oxyhemoglobin saturation. Jugular desaturation associated with arterial desaturation (hypoxemic cerebral hypoxia) was evaluated and managed.

A total of 121 episodes of combined arterial and jugular desaturation were documented, 76 in the presence of gross abnormalities identified on chest roentgenograms. Prolonged episodes that did not respond promptly to treatment occurred 32 times in 12 patients, usually after the initial 72 hours posttrauma. The remaining 89 episodes promptly responded to treatment and occurred predominantly within the initial 72 hours. Profound but brief desaturation was not associated with neurological deterioration, while profound and prolonged desaturation was accompanied by significant decreases in Glasgow Coma Scale scores, even though intracranial pressure levels were not significantly different in these two groups. Global cerebral hypoxia that does not respond promptly to treatment appears to be independently deleterious to neurological function in severely head-injured patients.
Video-assisted endoscopic thoracic ganglionectomy
Authors: Robertson Daniel P. , Simpson Richard K. , Rose James E. , Garza Jim S.
Published: May 2009

✓ Sympathetic nerve disorders of the upper extremities can be treated by neurosurgeons using upper thoracic sympathectomy via a posterior approach. Descriptions have been published of alternative endoscopic procedures involving thermocoagulation, laser coagulation, or nonvideo-assisted ganglionectomy using equipment not widely available, with low morbidity and excellent results. The authors describe the use of an endoscopic approach to the thoracic sympathetic ganglia with systems designed for laparoscopic cholecystectomy. Thoracic ganglionectomy is reported in 22 patients with primary palmar hyperhidrosis and eight patients with reflex sympathetic dystrophy. The patients underwent double-lumen endotracheal intubation, after which 11- and 5.5-mm trocars were introduced into the chest cavity. Pneumothorax was produced with CO2 insufflation. Fiberoptic closed-circuit television was used to visualize the structures to be dissected. The parietal pleura over the heads of the first and second ribs was excised using 5-mm blunt and sharp insulated coagulating microscissors. The stellate and upper thoracic ganglia were clearly identified and dissected. The T-2 and T-3 ganglia were grasped with forceps and excised. A No. 16 French chest tube was introduced through a trocar, placed under water seal after the lungs were reinflated, and removed in the recovery room. The average hospital stay was 15.4 hours. There were no intraoperative complications. The average operating time was 30 minutes per side. Five patients had mild pleuritic pain which resolved within 2 weeks after surgery. Six (75%) of the eight patients with reflex sympathetic dystrophy had complete or partial relief of their symptoms (average follow-up period 5 months), and all patients had complete relief of hyperhidrosis (average follow-up period 8 months). Endoscopic ganglionectomy requires readily available and easily used instrumentation and provides a well-tolerated, cost-effective alternative to posterior thoracic sympathectomy for primary palmar hyperhidrosis and reflex sympathetic dystrophy.
The effect of resuscitative moderate hypothermia following epidural brain compression on cerebral damage in a canineoutcome model
Authors: Pomeranz Shlomo , Safar Peter , Radovsky Ann , Tisherman Samuel A. , Alexander Henry , Stezoski William
Published: May 2009

✓ A canine model of temporary epidural cerebral compression and standardized intensive care was developed to evaluate the effect of resuscitative (postinsult) moderate systemic hypothermia. A balloon was inflated over the temporal region to maintain contralateral intraventricular pressure (IVP) at 62 mm Hg for 90 minutes. For a 66-hour period after initiation of brain compression, the intubated dogs received controlled ventilation and standard intensive care. From 66 to 90 hours postinjury, the extubated dogs were evaluated as to functional outcome. Morphological brain damage was evaluated at 90 hours or earlier if brain death occurred. Eight dogs in a control group were maintained at a body of temperature of 38°C. Eight treated dogs had core body temperature reduced by surface cooling starting 15 minutes after balloon inflation, first to 31°C for 5 hours and then to 35°C from 5 to 62 hours after insult.

Intraventricular pressure increased to 20 mm Hg or greater in the control group at a mean of 2.9 hours (range 2 to 4 hours) following the insult, and in the hypothermic group at a mean of 14.8 hours (range 5 to 30 hours) — that is, during the time period when the body temperature was 35°C, not 31°C (p = 0.01). There was no difference in peak pressures between the two groups. Brain death occurred in four of the eight dogs in the normothermic group at 18, 24, 24, and 48 hours (mean ± standard deviation 28 ± 13 hours) and in three of the eight in the hypothermic group at 27, 42, and 45 hours (mean 38 ± 10 hours) (not significant). The animals surviving 90 hours (four in the normothermic and five in the hypothermic group) were neurologically near normal. The total mean macroscopically damaged brain volume was 2584 ± 1890 cu mm in the normothermic versus 765 ± 611 cu mm in the hypothermic group (p = 0.03). The mean necrotic volume was 741 ± 599 cu mm in the normothermic versus 263 ± 346 cu mm in the hypothermic group (p = 0.07). Microscopically, the damaged regions consisted of ischemic neurons, reactive glia, edema, vascular endothelial hypertrophy, and erythrocyte extravasation. It is concluded that, in this model, immediate postinsult hypothermia of 31°C (not 35°C) for 5 hours prevents a rise in IVP and significantly decreases cerebral tissue damage, but does not prevent brain herniation during rewarming.
Hemin: levels in experimental subarachnoid hematoma and effects on dissociated vascular smooth-muscle cells
Authors: Letarte Peter B. , Lieberman Kristine , Nagatani Kazuhiko , Haworth Robert A. , Odell Gerard B. , Duff Thomas A.
Published: May 2009

✓ Although hemin is known to exert toxic effects on a variety of cell types, its possible participation in the genesis of cerebral vasospasm has received little attention. The authors measured the concentration of hemin in experimental subarachnoid clot and studied its effects on the morphology and 45Ca++ uptake of vascular smooth-muscle cells dissociated from canine carotid artery.

Craniectomies were performed in five dogs under general anesthesia, and 3 to 5 ml of autologous whole blood was deposited in the supraclinoid subarachnoid compartment. The concentration of hemin recovered by Folch extraction from clotted material removed 7 days after surgery was 390 ± 247 µM (mean ± standard error of the mean). Mean vascular smooth-muscle cell length after 40 minutes of exposure to 50 µM hemin was 37.3 ± 1.2 µm (control 51.6 ± 1.6 µm) (p < 0.01). The mean percent permeation of 45Ca++, measured by a dual label technique, of cells exposed to hemin was 200.9% ± 23% (control 102.9% ± 4.3%) (p < 0.01).

These findings indicate that hemin accrues in subarachnoid hematoma, that it exerts a constrictive effect on vascular smooth-muscle cells, and that this effect is associated with an increased uptake of Ca++. This study demonstrates that hemin should be included in the list of potential agents that participate in the development of cerebral vasospasm.
Microsurgical anatomy of the hippocampal arteries
Authors: Erdem Atilla , Yaşargil M. Gazi , Roth Peter
Published: May 2009

✓ An anatomical study of the vascularization of the hippocampus was performed on 30 hemispheres. There were a total of 140 arteries supplying the hippocampi, for an average of 4.7 arteries per hemisphere (range three to seven arteries). Based on the origin and caliber of the arteries supplying the hippocampus, the hemispheres were divided into five groups: A) in 57% of the hemispheres studied, the origin was mixed and included the anterior choroidal artery (AChA), the main trunk of the posterior cerebral artery (PCA), and the inferior temporal, lateral posterior choroidal, and splenial branches of the PCA; B) in 27%, all of the inferior temporal branches of the PCA predominantly supplied the hippocampus; C) in 10%, the anterior inferior temporal branch of the PCA was the predominant supplier: D) in 3%, the hippocampus was predominantly supplied by arteries originating from the main trunk of the PCA (Uchimura artery); and E) in 3%, the AChA gave origin to the hippocampal vessel.

It was found as a result of this study that the PCA directly and by its branches contributes much more to the blood supply of the hippocampal formation than the AChA. The uncal sulcus was found to be an important anastomotic site between the hippocampal branches of the AChA and the hippocampal branches of the PCA. In 26.6% of hemispheres, one of the hippocampal arteries arose from the lateral posterior choroidal artery. The splenial artery made a loop close to the extra ventricular part of the hippocampal tail and gave off multiple vessels to this structure in 36.6% of hemispheres. The finding that the AChA passes through the choroid fissure as a trunk and its later division into the lateral plexal and medial perforating branches within the choroid plexus may be of surgical significance.
Surgical treatment of partial epilepsy arising from the insular cortex
Authors: Roper Steven N. , Levesque Michel F. , Sutherling William W. , Engel Jerome
Published: May 2009

✓ Despite its documented connections with many limbic structures, the role of the insula in the etiology of partial seizures is poorly understood. Two patients are described in whom lesions of the insula were associated with intractable partial seizures. In the first patient, the seizures involved visceral sensory hallucinations followed by motor automatism. Seizures in the second patient began with somatic sensory hallucinations and then produced visceral motor effects. Both patients were found to have low-grade astrocytomas of the insula. In both instances, resection of the lesion and adjacent insular cortex resulted in a cure of the seizures. These cases are placed within the context of the existing literature on the subject.
Intracranial neurothekeoma (nerve-sheath myxoma)
Authors: Paulls Werner , Warmuth-Metz Monika , Sörensen Niels
Published: May 2009

✓ Neurothekeoma is a benign cutaneous nerve-sheath tumor. The authors describe the case of a 16-year-old girl with a parasellar neurothekeoma that was successfully removed. Magnetic resonance imaging with gadolinium administration revealed bright enhancement of the peripheral portions and nonhomogeneous uptake in the central areas, which corresponded histologically to the vascular capsule and the myxoid center. It was concluded that: 1) intracranial neurothekeoma does exist, and 2) surgical resection appears to be the definitive therapy.
Cervical cord compression by the anomalous vertebral artery presenting with neuralgic pain
Authors: Satoh Shuji , Yamamoto Nobutaka , Kitagawa Yoshinobu , Umemori Tsutomu , Sasaki Takashi , Iida Takaaki
Published: May 2009

✓ The authors report the case of a 59-year-old woman with progressive neck and arm pain that initially appeared in the neck and later extended to the shoulder and upper extremity. This pain was caused by compression of the cervical cord between the atlas and axis by the vertebral artery, and disappeared promptly following microvascular decompression.
Cranial bone grafts for use in posterior fixation of the cervical spine
Authors: Walters Beverly C.
Published: May 2009

✓ Bone grafts are usually an integral part of cervical spine fixation following spinal trauma. Unfortunately, many currently used bone graft donor sites (including the rib, iliac crest, and fibula) cause unacceptable patient morbidity, especially postoperative pain. A readily available source of autologous bone graft for posterior cervical fusion is the occipital bone. This membranous bone offers the advantage of strength and less bone resorption. It has been used at the Sunnybrook Health Science Centre for 4 years as a standard source of bone graft with no morbidity and excellent results for fusion.
Magnetic resonance angiography: a three-dimensional database for assessing arteriovenous malformations
Authors: Mehta Minesh P. , Petereit Daniel , Turski Patrick , Gehring Mark , Levin Allan , Kinsella Timothy
Published: May 2009

✓ Stereotactic angiography has long been the “gold standard” in the diagnosis of patients with arteriovenous malformations (AVM's). Although orthogonal or stereoshift images may suffice in discerning the shape and location of spherical malformations, an exact analysis and assessment of most nonspherical malformations are hampered by the fact that stereotactic angiographic images compress three-dimensional (3-D) data into two-dimensional views. As a consequence, the complex 3-D shape of an AVM can never be fully and truly discerned from conventional angiography. With the recent explosion of radiosurgical techniques, more and more AVM's are being treated noninvasively. These radiosurgical techniques require 3-D visualization to maximize nidus coverage and minimize normal brain irradiation. Alternatives to stereotactic angiography are therefore desperately needed. An entire new family of pulse sequences is now available that permits visualization of the vascular system using magnetic resonance imaging. A brief technical review of magnetic resonance angiography is presented, and its potential role(s) in the assessment and radiosurgical treatment of AVM's is explored.
Centrocentral anastomosis of the proximal nerve stump in the treatment of painful amputation neuromas of major nerves
Authors: Barbera Jose , Albert-Pamplo Rafael
Published: May 2009

✓ The term “centrocentral anastomosis” is used to describe the end-to-end connection across interposed nerve grafts between paired fascicular groups of the proximal stump of a severed nerve. In 22 patients harboring a painful terminal neuroma following amputation of a lower limb (20 neuromas on the sciatic nerve and two on the peroneal nerve), a centrocentral anastomosis was performed on the end of the sectioned nerve to treat pain that had not improved with conventional conservative treatment. Follow-up review at 1 year revealed that the typical neuroma pain had disappeared in all cases, although sporadic diffuse pain persisted in four. Where previous phantom sensation was present, no change was observed. The results presented here are consistent with laboratory findings demonstrating the absence of neuroma formation after centrocentral anastomosis. Therefore, this technique is recommended for the treatment of painful amputation neuroma.
Short-segment compression instrumentation for selected thoracic and lumbar spine fractures: the short-rod/two-claw technique
Authors: Benzel Edward C.
Published: May 2009

✓ The short-rod/two-claw (SRTC) technique of spine instrumentation was recently introduced for the treatment of thoracic and lumbar spine fractures. The use of this technique in 10 patients harboring wedge compression or burst fractures of the thoracic or lumbar spine is described.

Of three patients treated with the construct placed in a distraction mode, the average follow-up loss of angle (the difference between the immediate postoperative and follow-up midsagittal angle as measured on x-ray films) was 18.3°. Of the seven patients in whom the instrumentation was placed in a compression mode, the average observed loss of angle at follow-up examination was 1.6°. Two patients had a preoperative scoliotic deformity at the fracture site. and both deformities were exaggerated by the placement of the SRTC technique in compression. Although no patient experienced an adverse outcome and all achieved a solid fusion, the application of the SRTC technique of universal spine instrumentation in distraction was associated with an exaggerated loss of angle. Loss of angle and deformity exaggeration are not desirable and are preventable by strict patient selection and by applying the construct in a compression mode. It is emphasized that few patients are candidates for this form of instrumentation. When applicable. however, the advantages of decreased pain and stiffness and the elimination of the need for instrumentation removal make the SRTC and related short-segment techniques desirable alternatives to traditional methods of spinal fixation.
Excitatory amino acids in cerebrospinal fluid following traumatic brain injury in humans
Authors: Baker Andrew J. , Moulton Richard J. , MacMillan Vernon H. , Shedden Peter M.
Published: May 2009

✓ Evidence from models of traumatic brain injury implicates excitotoxicity as an integral process in the ultimate neuronal damage that follows. Concentrations of the excitatory amino acid glutamate were serially measured in the cerebrospinal fluid (CSF) of patients with traumatic brain injuries and in control patients for comparison. The purpose of the study was to determine whether glutamate concentrations were significantly elevated following traumatic brain injury and, if so, whether they were elevated in a time frame that would allow the use of antagonist therapy. Cerebrospinal fluid was sampled fresh from ventricular drains every 12 hours and analyzed using high-performance liquid chromatography for the excitatory amino acids. The peak concentrations of glutamate in the CSF of the 12 brain-injured patients ranged from 14 to 474 µM and were significantly higher than those in the three control patients, 4.9 to 17 µM (Mann-Whitney U-test, p < 0.02). Glutamate concentrations in five of the eight patients who were still being sampled on Day 3 were beyond the control group range. The implication of this study is that severely head-injured patients are exposed to high concentrations of a neurotoxic amino acid for days following injury and thus may benefit from antagonist intervention.
Spontaneous thrombosis of posterior cerebral artery aneurysm with angiographic reappearance
Authors: Atkinson John L. D. , Lane John I. , Colbassani Harold J. , Llewellyn D. Mark E.
Published: May 2009

✓ The case is presented of a 23-year-old man suffering ischemic brain infarction from spontaneous thrombosis of a left posterior cerebral artery P1–P2 junction aneurysm. Vasospasm and/or partial parent vessel occlusion were documented by magnetic resonance (MR) imaging and angiography. Repeat cerebral angiography and MR imaging 3 months later revealed patency of the posterior cerebral artery and luminal filling of a 1-cm fusiform aneurysm, which was successfully trapped at surgery.
Cosmetic mastoidectomy for the combined supra/infratentorial transtemporal approach
Authors: Couldwell William T. , Fukushima Takanori
Published: May 2009

✓ The authors describe a cosmetic mastoidectomy technique for use when performing a combined supra/infratentorial craniotomy and transtemporal exposure. The technique involves a single temporal suboccipital bone flap and cosmetic mastoidectomy, removing the outer table of bone for later replacement. Replacement of the outer table of mastoid bone enables tamponade of a fat graft against the dura to reduce the risk of postoperative cerebrospinal fluid leaks. The technique has been performed in eight patients treated for petroclival meningiomas with excellent cosmetic results.
Increased stroke risk predicted by compromised cerebral blood flow reactivity
Authors: Yonas Howard , Smith Holly A. , Durham Susan R. , Pentheny Susan L. , Johnson David W.
Published: May 2009

✓ The authors sought to determine risk for stroke in individuals with symptomatic carotid stenosis or occlusion based upon an assessment of cerebral blood flow (CBF) reserves. Vascular reserve was assessed by two consecutive xenon/computerized tomography (Xe/CT) CBF studies with intravenous acetazolamide introduced 20 minutes prior to the second study. Patients were assigned to one of two vasoreactivity groups. Group 2 included individuals who experienced a CBF reduction of more than 5% in at least one vascular territory and had a baseline flow of 45 cc/100 gm/min or less. Group 1 included all other individuals. Any territory with volume loss on CT of more than 50% was eliminated from analysis.

Sixty-eight individuals were followed at 6-month intervals for a mean of 24 months. In Group 1 two strokes were observed contralateral to the side with lowest reserve, for a stroke incidence of 4.4%; in Group 2 eight strokes were observed ipsilateral to the side with lowest reserve, for a stroke incidence of 36%. The latter group had a 12.6 times greater chance of stroke (p = 0.0007). History of stroke, history of transient ischemic attacks, baseline CBF, and degree of stenosis were not associated with an increased stroke rate. In this study, significantly compromised vascular reserves accompanied by relatively low initial flow identified individuals who subsequently demonstrated a significantly increased rate of ipsilateral stroke.