bluuebunny/crossref_metadata_2025 huggingface dataset:
Spinal tuberculosis: a diagnostic and management challenge
Authors: Nussbaum Eric S. , Rockswold Gaylan L. , Bergman Thomas A. , Erickson Donald L. , Seljeskog Edward L.
Published: June 2009

✓ The authors reviewed 29 cases of spinal tuberculosis treated from 1973 to 1993 with an average follow-up time of 7.4 years. Clinical findings included back pain, paraparesis, kyphosis, fever, sensory disturbance, and bowel and bladder dysfunction. Twenty-two patients (76%) presented with neurological deficit; 12 (41%) were initially misdiagnosed. Sixteen patients (55%) had predominant vertebral body involvement; nine had marked bone collapse with neurological compromise. Eleven individuals (39%) had intraspinal granulomatous tissue causing neurological dysfunction in the absence of bone destruction, and two (7%) had intramedullary tuberculomas.

All patients received antituberculous medications: 13 were initially treated with bracing alone, eight underwent laminectomy and debridement of extra- or intradural granulomatous tissue, and eight underwent anterior, posterior, or combined fusion procedures. No patient with neurological deficit recovered or stabilized with nonoperative management. Thirteen patients were readmitted with progression of inadequately treated osteomyelitis; 12 (92%) of these required new or more radical fusion procedures. Anterior fusion failure was associated with marked preoperative kyphosis and multilevel disease requiring a graft that spanned more than two disc spaces. Courses of antibiotic medications shorter than 6 months were invariably associated with disease recurrence.

It was concluded that 1) patients should receive at least 12 months of appropriate antituberculous therapy; 2) individuals with neurological deficit should undergo surgical decompression; 3) laminectomy and debridement are adequate for intraspinal granulomatous tissue in the absence of significant bone destruction; 4) when vertebral body involvement has produced wedging and kyphosis, aggressive debridement and fusion are indicated to prevent delayed instability and progression of disease.
Magnetic resonance image—directed stereotactic neurosurgery: use of image fusion with computerized tomography to enhance spatial accuracy
Authors: Alexander Eben , Kooy Hanne M. , van Herk Marcel , Schwartz Marc , Barnes Patrick D. , Tarbell Nancy , Mulkern Robert V. , Holupka Edward J. , Loeffler Jay S.
Published: June 2009

✓ Distortions of the magnetic field, such as those caused by susceptibility artifacts and peripheral magnetic field warping, can limit geometric precision in the use of magnetic resonance (MR) imaging in stereotactic procedures. The authors have routinely found systematic error in MR stereotactic coordinates with a median of 4 mm compared to computerized tomography (CT) coordinates. This error may place critical neural structures in jeopardy in some procedures. A description is given of an image fusion technique that uses a chamfer matching algorithm; the advantages of MR imaging in anatomical definition are combined with the geometric precision of CT, while eliminating most of the anatomical spatial distortion of stereotactic MR imaging.

A stereotactic radiosurgical case is presented in which the use of MR localization alone would have led to both irradiation of vital neural structures outside the desired target volume and underdose of the intended target volume. The image fusion approach allows for the use of MR imaging, combined with stereotactic CT, as a reliable localizing technique for stereotactic neurosurgery and radiosurgery.
Immunolocalization of cathepsin B in human glioma: implications for tumor invasion and angiogenesis
Authors: Mikkelsen Tom , Yan Pei-Sha , Ho Khang-Loon , Sameni Mansoureh , Sloane Bonnie F. , Rosenblum Mark L.
Published: June 2009

✓ The poor prognosis of patients with malignant gliomas is at least partially due to the invasive nature of these tumors. In this study, the authors investigated the possibility that the cysteine protease cathepsin B (CB) is a participant in the process of glial tumor cell invasion. To accomplish this, an immunohistochemical analysis was made of the localization of antibodies to CB in biopsies of five specimens of normal brain, 16 astrocytomas, 33 anaplastic astrocytomas, and 33 glioblastomas multiforme.

Staining was scored according to the percentage of positive cells and the intensity of the stain, graded from 0 to 3+. Staining for CB was not seen in any of five samples of normal brain except for occasional neuronal cell bodies and microglia. Only five (31%) of 16 astrocytomas showed a small percentage of positive cells (0.01%–3%) that were stained in a light, diffuse cytoplasmic pattern (1+). Twenty-nine (87.8%) of 33 anaplastic astrocytomas showed positive light, granular staining in 2% to 40% of cells. In anaplastic astrocytoma, the staining within a tumor was heterogeneous with intensities of 1+ (17%), 1+ to 2+ (29%), or 2+ (55%). In contrast, all 33 (100%) glioblastomas were positive in 10% to 90% of cells. The staining was present in a coarse, granular pattern with an intensity of 2+ (12%) or 3+ (88%). Tumor cells infiltrating into brain adjacent to malignant gliomas stained positively in 26 cases that could be evaluated for glioblastoma multiforme; these invading cells frequently followed penetrating blood vessels as typical “secondary structures of Scherer.” Moderate to intense CB staining associated with endothelial proliferation in high-grade tumors was also observed, especially in regions of tumor infiltration into adjacent normal brain. These results provide evidence consistent with the hypothesis that CB is functionally significant in the process of tumor invasion and angiogenesis in the clinical progression of the malignant phenotype in astrocytomas.
Experimental chronic compressive cervical myelopathy: effects of decompression
Authors: Harkey H. Louis , Al-Mefty Ossama , Marawi Isam , Peeler Dudley F. , Haines Duane E. , Alexander Lon F.
Published: June 2009

✓ Twelve dogs developed a delayed onset of neurological abnormalities from chronic cervical cord compression that was characteristic of myelopathy. The animals were divided into two groups and matched according to degree of neurological deficit. Six animals underwent decompression through removal of the anteriorly placed compressive device. Throughout the experiment, serial neurological examinations and somatosensory evoked potential studies were performed on each animal. Spinal cord blood flow measurements were obtained during each surgical procedure and at sacrifice. Magnetic resonance images were obtained after compression and before sacrifice.

All animals in the decompressed group showed significant neurological improvement after decompression; no spontaneous improvement in neurological function was seen in the compressed group. On pathological examination, irreversible changes including large motor neuron loss, necrosis, and cavitation were seen in four of the animals in the decompressed group and five in the compressed group.

Cervical spondylotic myelopathy in humans is known to respond to decompression; this study provides further evidence that this animal model for chronic compressive cervical myelopathy accurately reflects the disease process seen in humans.
Paradoxical progression of tuberculous lesions during chemotherapy of central nervous system tuberculosis
Authors: Rao G. Prakash , Nadh B. Rajendra , Hemaratnan A. , Srinivas T. V. , Reddy P. Kantha
Published: June 2009

✓ The peculiar phenomenon of paradoxical progression during the treatment of central nervous system tuberculosis is discussed. A few cases with this phenomenon were reported in the past, and the authors have treated four such cases. During the treatment for tuberculous meningitis, the four patients developed new lesions, mainly in the form of tuberculomas, which progressed for some time and later regressed. In all these cases the initial drug regimen was not changed, except for the addition of steroids for a short period at the time of deterioration. All four patients underwent ventriculoperitoneal shunt insertion during the course of treatment. The authors discuss the significance of the changes in the lesions and management of such cases, and review the literature.
Familial aneurysmal subarachnoid hemorrhage: a community-based study
Authors: Schievink Wouter I. , Schaid Daniel J. , Michels Virginia V. , Piepgras David G.
Published: June 2009

✓ The familial occurrence of intracranial aneurysms has been well described. However, intracranial aneurysms are not rare and the great majority of reported families consist of only two affected members. Therefore, the familial aggregation of intracranial aneurysms could be fortuitous. The authors investigated the familial occurrence of aneurysmal subarachnoid hemorrhage (SAH) in their community to determine whether family members of patients with a ruptured aneurysm are at an increased risk of developing an SAH.

All 81 patients from Rochester, Minnesota, who suffered an SAH between 1970 and 1989 from a proven aneurysmal rupture were identified, and they or their families were contacted and a family history was obtained. The number of expected SAHs among first-degree relatives was calculated using previously established age- and sex-specific incidence rates in the community of Rochester. Of the 81 index patients, 76 had complete follow up for family history. Fifteen (20%) of these 76 patients had a first- or second-degree relative with aneurysmal SAH. The number of observed first-degree relatives with aneurysmal SAH was 11, compared to an expected number of 2.66, giving a relative risk of 4.14 (95% confidence interval 2.06–7.40; p < 0.001).

In the authors' community, aneurysmal SAH was familial in one of five patients, and this familial aggregation was not fortuitous. The increase in familial risk of aneurysmal SAH is approximately fourfold among first-degree relatives.
Hydrocephalus associated with intramedullary low-grade gliomas
Authors: Cinalli Giuseppe , Sainte-Rose Christian , Lellouch-Tubiana Arielle , Sebag Guy , Renier Dominique , Pierre-Kahn Alain
Published: June 2009

✓ Over the past 15 years, eight children affected by intramedullary low-grade gliomas associated with hydrocephalus were treated at l'Hôpital des Enfants Malades. In all cases the diagnosis of hydrocephalus was made prior to that of the spinal tumor. Neuroradiological examination of all patients revealed contrast enhancement of the intracranial subarachnoid spaces. In six cases this was progressive, suggesting subarachnoid spread of the tumor, which was confirmed in two cases by histological examination.

The authors analyzed 38 cases of intramedullary low-grade glioma associated with hydrocephalus that were reported in the literature. Fifteen of the cases had intracranial leptomeningeal seeding. Several hypotheses have been proposed to explain this unusual association, such as 1) increase in cerebrospinal fluid (CSF) viscosity because of elevated fluid protein content; 2) obliteration of the cisterna magna due to a rostral extension of the tumor; and 3) blockage of the spinal subarachnoid pathways of CSF resorption. Two other theories seem of particular interest. Bamford and Labadie suggested that the abnormal presence of fibrinogen in the CSF and its transformation into fibrin at the level of the basal cisterns and Pacchioni's granulation may alter CSF hydrodynamics. This mechanism alone is sufficient to induce hydrocephalus of the communicating type. In addition, as suggested by Maurice-Williams and Lucey, the resulting leptomeningeal fibrosis might predispose secondary implantation of neoplastic elements in the subarachnoid spaces of the intracranial compartment.
Negative-pressure hydrocephalus
Authors: Vassilyadi Michael , Farmer Jean-Pierre , Montes José L.
Published: June 2009

✓ Two cases of children with closed myelodysplasia, Arnold-Chiari malformation, and shunted hydrocephalus who underwent spinal arachnoid cystopleural shunting are presented. Postoperatively, both patients developed craniovertebral symptomatology accompanied by radiologically documented ventricular dilation in spite of negative intracranial pressure and functional ventriculoperitoneal (VP) shunts. Both patients recovered after the cystopleural shunts were revised to increase the resistance to flow within the system. The authors believe that some communication between the arachnoid cyst and the subarachnoid space existed in both cases and that the negative pleural pressure was transmitted preferentially to the spinal and cerebral convexity subarachnoid spaces with relative sparing of the ventricular system. A transmantle pressure gradient was thereby established, leading to ventricular dilation. The authors further suggest that a craniospinal gradient was possibly established as well, leading to craniovertebral symptomatology in the patients. Return of flow in the VP shunts was obtained by correcting this iatrogenic transmantle pressure gradient.
Loss of forebrain cholinergic neurons following fluid-percussion injury: implications for cognitive impairment in closed head injury
Authors: Schmidt Richard H. , Grady M. Sean
Published: June 2009

✓ Disturbances in memory, concentration, and problem solving are common after even mild to moderate traumatic brain injury. Because these functions are mediated in part by forebrain cholinergic and catecholaminergic innervation, in this study the authors sought to determine if experimental concussive injury produces detectable morphological damage to these systems.

Fluid-percussion head injury, sufficient to cause a 13- to 14-minute loss of righting reflex, was produced in rats that had been anesthetized with halothane. Injury was delivered either at midline or 2 mm off midline and compared with appropriate sham-injured controls. After 11 to 15 days, the rat brains were stained in serial sections for choline acetyltransferase, tyrosine hydroxylase, dopamine β-hydroxylase, acetylcholinesterase, and nicotinamide adenine dinucleotide phosphate diaphorase. Cell counts were determined for the entire population of ventrobasal forebrain cholinergic cells. Midline injury produced a bilateral loss of cholinergic neurons averaging 36% in area Ch1 (medial septal nucleus), 45% in Ch2 (nucleus of the diagonal band of Broca), and 41% in Ch4 (nucleus basalis of Meynart), (p ≤ 0.05). Lateralized injury resulted in cholinergic neuron loss of similar magnitude ipsilaterally (p ≤ 0.05), but a smaller contralateral loss of between 11% and 28%. No loss of neurons was detected in the pontomesencephalic cholinergic groups Ch5 and Ch6. There was no visible effect of head injury on forebrain dopamine or noradrenergic innervation.

A significant and apparently selective loss of ventrobasal forebrain cholinergic neurons following brief concussive injury in rats is demonstrated in this study. This type of injury is known to produce significant disturbance in cognitive tasks linked to neocortical and hippocampal cholinergic function. It remains to be determined how this neuron loss occurs, whether it can be prevented with neuroprotective agents, how it affects innervation in target tissues, and whether it occurs in human victims of traumatic brain injury.
Genesis of a dural arteriovenous malformation in a rat model
Authors: Herman James M. , Spetzler Robert F. , Bederson Joshua B. , Kurbat James M. , Zabramski Joseph M.
Published: June 2009

✓ A rat model was developed to determine the role of sinus thrombosis and elevated sinus pressures in the pathogenesis of dural arteriovenous malformations (AVMs) Five protocols were tested to compare various sinus pressures and thrombosis of a sinus: 1) Control I, sham operation (five animals); 2) Control II, occlusion of the right common carotid artery, the right external jugular vein, and the vein draining the left transverse sinus, as well as thrombosis of the sagittal sinus (10 animals); 3) arteriovenous fistula (AVF) I, anastomosis of the right common carotid artery to the external jugular vein causing retrograde flow through the transverse sinus (10 animals); 4) AVF II, anastomosis (as described in AVF I) and thrombosis of the sagittal sinus (12 animals); 5) AVF III, anastomosis (as described in AVF I) as well as thrombosis of the sagittal sinus and occlusion of the vein draining the transverse sinus on the left (12 animals). Mean arterial and sagittal sinus pressures were monitored and cerebral angiograms were obtained intraoperatively and again 90 days later. Afterward, the animals were sacrificed and their brains and dura were examined histologically.

Formation of a fistula resulted in a significant (p < 0.05) threefold increase in sagittal sinus pressure in the AVF II group and a significant (p < 0.05) sixfold increase in the AVF III group. Seven dural AVMs (three in the AVF II group and four in the AVF III group) were demonstrated angiographically and histologically. The seven malformations were located adjacent to a thrombosed sagittal sinus. All lesions were within the dura and sinus wall with direct thrombus—sinus wall connections demonstrated in four of the malformations. The other three lesions displayed arteriovenous connections within the sinus wall and dura. These data suggest the importance of not only sinus thrombosis but also sinus hypertension in the development of a dural AVM.
Spontaneous carotid—jugular fistula and carotid dissection in a patient with multiple intracranial arachnoid cysts and hemifacial atrophy: a generalized connective tissue disorder?
Authors: Schievink Wouter I. , Piepgras David G. , Nichols Douglas A.
Published: June 2009

✓ The authors report a case of a 45-year-old woman with pulsatile tinnitus who was found to have an unusual spontaneous fistula between the petrous internal carotid artery and internal jugular vein. The fistula resolved spontaneously, possibly related to daily manual compression of the ipsilateral common carotid artery. The patient also had a contralateral carotid artery dissection, multiple intracranial arachnoid cysts, and hemifacial atrophy. Her medical history was significant for easy bruisibility, abnormal scarring, and mitral valve prolapse. This association appears unique and may represent a previously undescribed generalized connective tissue disorder.
Survival after surgical treatment of brain metastases from lung cancer: a follow-up study of 231 patients treated between 1976 and 1991
Authors: Wroński Marek , Arbit Ehud , Burt Michael , Galicich Joseph H.
Published: June 2009

✓ The authors reviewed the records of 231 patients who underwent resection of brain metastases from nonsmall-cell lung cancer between 1976 and 1991. Data regarding the primary disease and the characteristics of brain metastasis were retrospectively collected. Median survival in the group from the time of first craniotomy was 11 months; postoperative mortality was 3%. Survival rates of 1, 2, 3, and 5 years were 46.3%, 24.2%, 14.7%, and 12.5%, respectively. One hundred twelve women survived significantly longer than 119 men (13.8 vs. 9.5 months, p < 0.02). Patients with single metastatic lesions (200 patients) survived longer than those (31 patients) with multiple metastases (11.1 vs. 8.5 months, p < 0.02). Patients with supratentorial tumors survived longer than patients with cerebellar lesions. A high Karnofsky performance scale score before surgery also indicated increased survival. In multivariate analyses, incomplete resection or no resection of primary lung tumor, male gender, infratentorial location, presence of systemic metastases, and age older than 60 years were significantly correlated with shorter survival. Approximately one-third of the patients died of neurological causes, one-third of systemic disease, and one-third of a combination of both. The results of this series confirm that the overall prognosis for patients with even a single resectable brain metastasis is poor, but that aggressive therapy can prolong life with quality of life preserved and can occasionally permit long-term survival.
A posterolateral microsurgical approach to extreme-lateral lumbar disc herniation
Authors: O'Brien Michael F. , Peterson David , Crockard H. Alan
Published: June 2009

✓ Extreme-lateral lumbar disc herniations present a surgical challenge because the conventional posterior approach requires bone resection for complete visualization of the pathology. The authors have identified constant anatomical landmarks in cadaveric dissections that facilitate access to the intervertebral foramen when combined with a posterolateral approach, as described by Watkins, for lumbar spinal fusion. The authors describe a technique that allows rapid localization and safe excision of these extreme-lateral lumbar disc herniations without the need for bone resection.
Inhibition of proliferation and induction of differentiation in medulloblastoma- and astrocytoma-derived cell lines with phenylacetate
Authors: Stockhammer Gunther , Manley Geoff T. , Johnson Robert , Rosenblum Marc K. , Samid Dvorit , Lieberman Frank S.
Published: June 2009

✓ The authors investigated the effects of a nontoxic differentiation inducer, phenylacetate (PA), on neuroectodermal tumor—derived cell lines. Treatment of medulloblastoma (Daoy and D283 MED) and glioma (U-251MG, C6, and RG2) cell lines resulted in a dose-dependent decline in DNA synthesis and cell proliferation, associated with accumulation in the G0/G1 phase of the cell cycle. Phenylacetate decreased transforming growth factor (TGF)—β2 production by medulloblastoma Daoy cells. Neutralizing antibodies against either TGFβ2 or TGFβ1 failed to block the growth arrest observed. This suggests that, unlike other differentiation agents, such as retinoic acid, the effect of PA on medulloblastoma proliferation is not mediated by a TGFβ pathway. In addition to cytostasis, PA induced marked morphological changes in U-251MG and C6 glioma cells associated with increased abundance of glial fibrillary acidic protein—positive processes. Although the morphology of PA-treated medulloblastoma cells was not significantly altered, the D283 MED cells exhibited increased expression of neurofilament proteins and Hu antigen, indicative of differentiation along a neuronal pathway. The effects of PA on the medulloblastoma cell lines were compared to its effects on the human neuroblastoma cell line BE(2)C, which is capable of a bidirectional differentiation toward a neuronal or a glial/schwann cell pathway. In BE(2)C cells, PA induced differentiation toward a schwann/glial cell-like phenotype, suggesting that the choice of differentiation pathway is cell type and agent specific. These in vitro antiproliferative and differentiation inducing effects of PA suggest that this agent warrants further evaluation as a potential therapeutic modality for the treatment of medulloblastoma and malignant glioma in humans.
Evidence for clonal spread in the development of multiple meningiomas
Authors: Larson Jeffrey J. , Tew John M. , Simon Matthias , Menon Anil G.
Published: June 2009

✓ Meningiomas are common intracranial tumors that arise from the arachnoid cells of the meninges. Occasionally patients develop multiple meningiomas. Because the underlying mechanism of multiple meningioma formation is unknown, the authors examined the pattern of X chromosome inactivation in multiple meningiomas. Fifteen intracranial meningiomas were resected in four patients with multiple meningiomas to determine whether the tumors in patients with multiple meningiomas originate from a common progenitor cell or arise independently. Specimens were examined using polymerase chain reaction assays to detect the pattern of X chromosome inactivation. In each patient, all tumors showed inactivation of the same X chromosome, suggesting that tumors arose from the same clone of cells (p <0.0005). The authors conclude that multiple meningiomas arise from the uncontrolled spread of a single progenitor cell.
Repair of critical size rat calvarial defects using extracellular matrix protein gels
Authors: Sweeney Thomas M. , Opperman Lynne A. , Persing John A. , Ogle Roy C.
Published: June 2009

✓ In this study the authors examined the capacity of gels of reconstituted basement membrane, laminin, and type I collagen to mediate repair of critical size defects in rat calvaria. Although autografts are widely used to repair bone defects caused by trauma or surgical treatment of congenital malformations, neoplasms, and infections, an adequate quantity of graft is not always available. Allogenic bone is readily available, but its use is associated with an increased incidence of nonunion, fatigue fracture, and rejection. Biologically active, purified components of basement membranes, which have been shown to promote osteogenic differentiation and angiogenesisin vitroand type I collagen (the major constituent of bone extracellular matrix) can be formed into native isotonic space-filling gels.

In this study critical size calvarial defects were created in retired male Sprague-Dawley rats. Thirty-six animals were divided into seven groups. Group 1 (control) received no treatment for the defects. Group 2 animals were implanted with methylcellulose. Groups 3, 4, 5, and 6 were implanted with gels of type I collagen, reconstituted basement membrane, or laminin, respectively. The last group of three animals (Group 7) was implanted with 100 µg of type I collagen gels (identical to Group 3) and sacrificed at 20 weeks following a single CT scan to determine if complete healing could be obtained with this method given sufficient time. Except for rats in the type I collagen group that was evaluated by multiple computerized tomography (CT) scans biweekly from 2 to 12 weeks, bone repair was evaluated using CT at 12 weeks. Healing was quantified using three-dimensional reconstruction of CT. Following the final CT scan in each experimental group, animals were sacrificed, and a sample of tissues was evaluated by conventional histology. Animals treated with type I collagen gels showed 87.5% repair of the area of the defects at 12 weeks and 92.5% repair by 20 weeks. Increasing the gel volume 1.5 × accelerated complete repair to 3 months. Murine-reconstituted basement membrane and laminin gels induced 55.5% and 46.3% repair, respectively, at 3 months. In untreated control animals 7% repair of the area of the defects showed at 3 months. Histological analysis confirmed new bone formation in partial and completely healed defects. Bioengineered native collagen gels may have wide applicability for bone repair as an alternative bone graft material alone, in combination with autograft or marrow aspirate, or as a delivery system for osteogenic growth factors.
Isolated intramedullary histiocytosis-X of the cervical spinal cord
Authors: Hamilton Bruce , Connolly Edward S. , Mitchell William T.
Published: June 2009

✓ Histiocytosis-X is known to involve the central nervous system, but rarely does this disease involve the spinal cord. To the authors' knowledge, this is the first case of isolated intramedullary histiocytosis-X of the spinal cord to be reported.
Long-term prognosis and effect of endarterectomy in patients with symptomatic severe carotid stenosis and contralateral carotid stenosis or occlusion: results from NASCET
Authors: Gasecki Andrew P. , Eliasziw Michael , Ferguson Gary G. , Hachinski Vladimir , Barnett Henry J. M. , _ _
Published: June 2009

✓ The purpose of this study was to examine how the prognosis of patients who presented with a recent ischemic event referable to a 70% to 99% stenosis of one carotid artery (ipsilateral) was altered by stenosis and occlusion of the contralateral carotid artery. The benefit of performing carotid endarterectomy on the recently symptomatic artery, in the presence of contralateral artery disease, was also examined.

A total of 659 patients were grouped into one of three categories according to the extent of stenosis in the contralateral carotid artery: less than 70% (559 patients), 70% to 99% (57 patients), and occlusion (43 patients). Strokes that occurred during the follow-up period were designated as ipsilateral if they arose from the same carotid artery as the symptom for which the patient had been entered into the study. Medically treated patients with an occluded contralateral artery were more than twice as likely to have had an ipsilateral stroke at 2 years than patients with either severe (hazard ratio: 2.36; 95% confidence interval (CI): 1.00–5.62) or mild-to-moderate (hazard ratio: 2.65; 95% CI: 1.43–4.90) contralateral artery stenosis. The perioperative risk of stroke and death was higher in patients with an occluded contralateral artery (4.0% risk) or mild-to-moderate (5.1% risk) contralateral stenosis. Regression analyses indicated that the results were not affected by other risk factors.

An occluded contralateral carotid artery significantly increased the risk of stroke associated with a severely stenosed ipsilateral carotid artery. Despite higher perioperative morbidity in the presence of an occluded contralateral artery, the longer-term outlook for patients who had endarterectomy performed on the recently symptomatic, severely stenosed ipsilateral carotid artery was considerably better than for medically treated patients.
Prolonged external ventricular drainage with percutaneous long-tunnel ventriculostomies
Authors: Khanna Rohit K. , Rosenblum Mark L. , Rock Jack P. , Malik Ghaus M.
Published: June 2009

✓ External ventricular drainage has been used extensively for management of several neurosurgical disorders. The main limitation of this procedure has been the high risk of infection, especially with prolonged drainage. In an effort to minimize the risk of infection, the authors have used a new ventriculostomy technique that involves tunneling the ventricular catheter subcutaneously to an exit site in the lower chest or upper abdomen. This report describes the results of this procedure on 100 consecutive cases. Patients requiring emergency ventriculostomies had short-tunnel ventriculostomies placed at the bedside that were converted to long-tunnel ventriculostomies in the operating room within 5 days. The average duration of drainage was 18.3 days (range 5–40 days). Cerebrospinal fluid was routinely sent for Gram staining and culture to monitor for infection. Prophylactic antibiotic medications were administered only perioperatively. No infection was observed during the first 16 days of drainage in any patient. The overall incidence of infection was 4% and blockage occurred in 6% of the cases. In this series the incidence of ventricular infection was 2.37 per 1000 ventricular drainage days, one of the lowest reported incidences of infection in the literature. This procedure provides a simple and effective method of maintaining long-term ventricular drainage with a very low risk of infection or blockage.
Localization of inactive cerebrospinal fluid fistulas
Authors: Eljamel Muftah S. , Pidgeon Christopher N.
Published: June 2009

✓ Because of the importance of preoperative localization of dural fistulas, many imaging modalities have been critically evaluated for their role in pinpointing the site of cerebrospinal fluid (CSF) leakage. Twenty-one consecutive patients who were suspected of having a CSF fistula were studied to evaluate magnetic resonance (MR) imaging in locating the fistula. These patients were also studied independently by fine-slice computerized tomography (CT). The MR images demonstrated lesions compatible with dural fistulas in 19 patients, whereas CT demonstrated only seven of these lesions. All of these patients underwent surgical dural repair. The remaining two patients underwent surgical exploration on the basis of the CT findings but no dural fistula was found in either patient. All patients made a good postoperative recovery. One patient developed a postoperative wound infection and in another CSF leakage recurred. Although MR imaging was very precise in locating the CSF fistulas, CT missed a significant number of these lesions and was falsely positive in 9.5% of cases. Therefore, it is concluded that MR imaging is an essential investigation in patients with a suspected dural fistula and should be performed before embarking upon surgery and before assuming natural healing of the CSF fistula.
The natural history of cerebral cavernous malformations
Authors: Kondziolka Douglas , Lunsford L. Dade , Kestle John R. W.
Published: June 2009

✓ To determine the natural history of brain cavernous malformations, the authors entered patients referred to their center into a prospective registry between 1987 and 1993. All patients underwent magnetic resonance imaging, which showed the typical appearance of this lesion, and conservative management was recommended in all. Patients or their referring physicians were contacted for follow-up data. The purpose of the study was to define the rate of symptomatic hemorrhage and to determine the outcome in those patients who had suffered seizures.

Follow-up data were available for 122 patients with a mean age at entry of 37 years (range 4–82 years). The malformation was located in the brainstem in 43 cases (35%), the basal ganglia/thalamus in 20 (17%), and a hemispheric area in 59 (48%). Fifty percent of patients had never had a symptomatic hemorrhage, 41% had one bleed, 7% had two, and 2% had three. Seizures were reported in 23% of patients and headaches in 15%. Lesions were solitary in 80% of patients and multiple in 20%. The retrospective annual hemorrhage rate (61 bleeds/4550.6 patient-years of life) was 1.3%.

The mean prospective follow-up period was 34 months. There were nine bleeds during this time, six with new neurological deficits. In patients without a prior bleed, the prospective annual rate of hemorrhage was 0.6%. In contrast, patients with prior hemorrhage had an annual bleed rate of 4.5% (p = 0.028). Patient sex (p = 0.97) or the presence of seizures (p = 0.11), headaches (p = 0.06), or solitary versus multiple lesions (p = 0.15) were not significant predictors of later hemorrhage. There was no difference in the rate of bleeds between brain locations. Four patients with seizures became seizurefree and four patients without seizures later developed seizures; only one patient developed intractable seizures. Fourteen patients (11%) underwent surgery (two after hemorrhage, five with seizures, and seven with progressive deficits), and five had radiosurgery. No patient died in the follow-up period. This study indicates that conservative versus operative management strategies may need to be redefined, especially in patients who present with hemorrhage and who appear to have a significantly increased risk of subsequent rehemorrhage.
Neurosurgical management of cerebral aneurysms following unsuccessful or incomplete endovascular embolization
Authors: Gurian John H. , Martin Neil A. , King Wesley A. , Duckwiler Gary R. , Guglielmi Guido , Viñuela Fernando
Published: June 2009

✓ Modern endovascular techniques permit treatment of intracranial aneurysms in many circumstances when surgery is associated with significant morbidity. Occasionally, embolization of aneurysms is unsuccessful or incomplete or followed by complications, in which case surgical management is required. Since 1986, 196 patients have undergone embolization of intracranial aneurysms at the authors' institution and 21 (11%) required subsequent surgical treatment. Attempted embolization failed in five patients (Group A). Ten patients (Group B) had only partial occlusion of the aneurysm or demonstrated recanalization on follow-up studies. Eight of these Group B patients underwent embolization with Guglielmi detachable coils (GDCs), representing 5.7% of the 141 GDC-treated patients in this experience. Surgical treatment in these two groups consisted of clipping (eight cases), surgical parent vessel occlusion (one case), and parent vessel occlusion with extracranial—intracranial bypass (six cases). Fourteen (93%) of the 15 patients in these two groups had an excellent or good outcome with complete aneurysm occlusion. Six patients underwent surgery to treat complications related to the endovascular procedure (Group C). Of these, four patients had neurological improvement compared to their preoperative state, and two died. This series of cases demonstrates that surgical treatment of aneurysms is usually possible with good results following incomplete embolization and emphasizes the need for close and continued neurosurgical involvement in the endovascular management of intracranial aneurysms.
Hemin activation of an inducible isoform of nitric oxide synthase in vascular smooth-muscle cells
Authors: Suzuki Satoshi , Kassell Neal F. , Lee Kevin S.
Published: June 2009

✓ Hemin is a prominent breakdown product of hemoglobin, and high levels of hemin are found in the cerebrospinal fluid during subarachnoid hemorrhage—induced vasospasm. The possible role of hemin in modifying vascular function was examined in the present study by testing its effects on nitric oxide synthase (NOS) activity in cultured rat aortic smooth-muscle cells. Nitric oxide synthase activity was estimated from the amounts of accumulated nitrite and nitrate, which are oxidative products of nitric oxide (NO). Hemin (1–100 µM) increased the levels of nitrite and nitrate in culture medium in a dose- and time-dependent manner. The hemin-induced elevation of nitrite and nitrate was inhibited significantly by the NOS inhibitor, Nω-nitro-l-arginine (300 µM), and by the protein synthesis inhibitor, cycloheximide (5 µg/ml). These results indicate that hemin is capable of stimulating the expression of an inducible isoform of NOS (iNOS) in vascular smooth muscle. Transcriptional expression of iNOS is known to cause injurious effects on the maintenance of cellular homeostasis by generating extremely high levels of NO. The generation of hemin from methemoglobin during hemolysis of a subarachnoid blood clot could therefore stimulate an excessive production of NO in vascular smooth-muscle cells. It is postulated that this series of events contributes to the development of vascular injury associated with cerebral vasospasm after aneurysmal subarachnoid hemorrhage.
Mandibular subluxation as an adjunct to exposure of the distal internal carotid artery in endarterectomy surgery
Authors: Frim David M. , Padwa Bonnie , Buckley Deidre , Crowell Robert M. , Ogilvy Christopher S.
Published: June 2009

✓ The location of the carotid artery bifurcation and the distance atherosclerotic disease extends distally in the internal carotid artery (ICA) are two factors that contribute to the technical difficulty of carotid endarterectomy. When the bifurcation is high (above C-3) or the disease extends distally, standard approaches may not provide adequate exposure for dissection of plaque or for arteriotomy repair. A simple method of mandibular subluxation is described for added exposure of the distal carotid artery. The criteria for use of this method include: a carotid bifurcation at or above C-2; disease extending to within 2 cm of the skull base; and a small-caliber distal ICA lumen with the expectation of a patch graft extending close to the skull base. In dentulous patients, the mandible is subluxed by attaching an intradental wire from the ipsilateral mandibular bicuspid to an intradental wire around the contralateral maxillary bicuspid. In edentulous patients, a wire is placed around the ipsilateral mandible and secured to a wire placed through the anterior nasal spine. The entire preoperative subluxation requires 10 to 15 minutes under anesthesia and an additional 1 to 2 minutes postoperatively to remove the wires. A single skin suture and an absorbable intraoral suture were placed in some edentulous patients.

This technique has been evaluated over a 15-month reference period during which 115 carotid endarterectomies were performed. The criteria stated above were met in seven cases (six patients, 6%) and jaw subluxation was performed preoperatively. An additional 1 to 2 cm of distal exposure was obtained by using this technique and endarterectomy proceeded without complication. A slight “shift” of the standard anatomical landmarks occurred due to the movement of the mandible, which was easily recognized. There were no significant postoperative complaints related to the subluxation; specifically, no temporomandibular joint pain, no other postoperative pain, and no tooth damage were encountered. It is concluded that this relatively simple approach to mandibular subluxation provided significant added exposure to the distal ICA without notably increasing operative time. In addition, there was no morbidity and little additional care was needed when compared with other more radical approaches to high carotid artery exposure.
Apoptosis of human glioma cells in response to calphostin C, a specific protein kinase C inhibitor
Authors: Ikemoto Hideyasu , Tani Eiichi , Matsumoto Tsuyoshi , Nakano Atsuhisa , Furuyama Jun-Ichi
Published: June 2009

✓ Calphostin C acts at the regulatory domain as a highly selective inhibitor of protein kinase C (PKC), and staurosporine acts at the catalytic domain as a nonspecific PKC inhibitor. The authors investigated the capacity of calphostin C and staurosporine to promote apoptotic fragmentation of DNA in four human glioma cell lines. The exposure of glioma cell lines to 100 nM calphostin C for 2 to 8 hours induced a decrease in particulate PKC activities and exposure for 16 to 24 hours produced a concentration-dependent increase in internucleosomal DNA cleavage on agarose gel electrophoresis. In addition, the human glioma cells showed the classic morphological features of apoptosis: cell shrinkage, nuclear condensation, and the formation of apoptotic bodies. A 24-hour exposure to staurosporine failed to induce internucleosomal DNA fragmentation at concentrations generally used to achieve maximum inhibition of enzyme activity (50 nM) but promoted fragmentation at considerably higher concentration (more than 200 nM). Deoxyribonucleic acid fragments obtained from cells exposed to 100 nM calphostin C for 16 to 24 hours possessed predominantly 59-phosphate termini, consistent with the action of a Ca++/Mg++-dependent endonuclease. Northern and Western blot analyses revealed that the exposure to 100 nM calphostin C for 4 hours failed to alterbcl-2 transcript and protein, but exposure for more than 8 hours decreased the amount ofbcl-2 transcript and protein. Together, these observations suggest that calphostin C is capable of inducing apoptotic DNA fragmentation and cell death in a highly concentration dependent manner in human glioma cells and that the apoptosis is closely associated with the decrease in transcription and translation ofbcl-2.
Brain edema and neurological status with rapid infusion of lactated Ringer's or 5% dextrose solution following head trauma
Authors: Feldman Zeev , Zachari Serj , Reichenthal Eli , Artru Alan A. , Shapira Yoram
Published: June 2009

✓ Rapid infusion of 0.25 ml/g of 0.9% saline over 30 minutes has been shown to have no effect on electrolyte balance, neurological severity score (NSS), or brain edema, following closed head trauma (CHT). Rapid infusion of the same volume of 5% dextrose solution decreased blood sodium concentration, increased edema, and decreased NSS following CHT. In the present study the authors examined the effect of rapid infusion (30 minutes) of smaller volumes of 5% dextrose (0.08 ml/g and 0.16 ml/g) and of 0.25 ml/g lactated Ringer's solution on blood electrolyte concentrations, plasma osmolality, brain edema, and NSS. The purposes of this study were to determine whether rapid infusion of a large volume of lactated Ringer's solution could be given after CHT without increasing mortality or brain edema or producing electrolyte disturbances, and whether small volumes of 5% dextrose could be infused with few or none of the deleterious effects expected from large volumes of 5% dextrose. One hundred eighteen rats, which survived halothane anesthesia and CHT, were randomly assigned to one of 15 experimental groups. Fluids were administered beginning 1 hour after scalp incision or CHT. The NSS, extent of edema, blood electrolyte concentrations, and plasma osmolality in the groups treated with lactated Ringer's solution were not significantly different from those values in the nontreated groups. In addition, the mortality rate after CHT was not increased by administration of lactated Ringer's solution. The groups treated with 5% dextrose solution showed a significantly higher mortality rate, but the NSSs of the surviving rats were not different from controls. None of the groups treated with 0.16 ml/g 5% dextrose solution survived 24 hours. Although blood glucose concentration increased to 1126 ± 102 g% (mean ± standard deviation) and 1568 ± 283 g% and blood sodium concentration decreased to 110.4 ± 4.6 mEq/L and 92.0 ± 5.2 mEq/L in the groups treated with 0.08 ml/g and 0.16 ml/g of 5% dextrose solution, respectively, plasma osmolality was normal and no significant difference could be found between the brain tissue specific gravity of animals in the nontreated and 5% dextrose treatment groups. It is concluded that in the CHT model used in this study, the large volume of lactated Ringer's solution did not affect blood electrolyte concentration, neurological outcome, or formation of brain edema, whereas smaller volumes of 5% dextrose solution increased blood glucose and decreased blood sodium concentrations, did not affect plasma osmolality, and had a deleterious effect on neurological outcome.
Chemical Composition and Antibacterial Activity of the Essential Oils of Callistemon citrinus and Callistemon viminalis from South Africa
Authors: Oyedeji Opeoluwa  O. , Lawal Oladipupo.  A. , Shode Francis.  O. , Oyedeji Adebola.  O.
Published: June 2009

The chemical composition and the antibacterial activity of the essential oils obtained by hydrodistillation from the leaves of Callistemon citrinus and Callistemon viminalis were analyzed by GC and GC/MS. Twenty-four and twelve components were identified for C. citrinus and C. viminalis, representing 92.0% and 98.3% of the total oils. The major components of C. citrinus and C. viminalis were 1,8-cineole (61.2% and 83.2%) and α-pinene (13.4% and 6.4%), respectively. The in vitro antibacterial activity of the essential oils was studied against 12 bacteria strains using disc diffusion and broth microdilution methods. The oils exhibited strong zone of inhibitions against some bacteria such as S. faecalis (20.3-24.0 mm), both strains of S. aureus (23.0-26.3 mm), B. cereus (17.3-19.0 mm) and S. macrcesens (11.3-23.7 mm) when compared to standard antibiotics gentamycin and tetracycline used as controls. Expect for P. aeruginosa and S. macrcescens, the MIC values of both essential oils ranged from 0.31-2.50 mg/mL.
Greater Perceived Helplessness in Osteoarthritis Predicts Outcome of Joint Replacement Surgery
Authors: GANDHI RAJIV , RAZAK FAHAD , TSO PEGGY , DAVEY J. RODERICK , MAHOMED NIZAR N.
Published: June 2009

Objective.

To determine if there is a difference between male and female patients in their perceived control of osteoarthritis (OA) symptoms at the time of joint replacement surgery, as measured by the Arthritis Helplessness Index (AHI), and how this helplessness affects surgical outcomes at 1 year.

Methods.

From a joint replacement registry, 70 male and 70 female patients were randomly selected and matched for age, body mass index, comorbidity, procedure, and education. Patients completed the AHI prior to surgery. Functional status was assessed at baseline and 1-year followup with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. Linear regression modeling was used to determine the effect of sex on predicting AHI scores. A second model was constructed to examine the effect of AHI on the 1-year WOMAC change score.

Results.

There were no statistically significant differences in demographic data or clinically significant differences in AHI scores between sexes. Linear regression modeling showed that female sex was a significant predictor of a greater AHI score prior to surgery (p < 0.05). Moreover, a greater AHI score was an independent predictor of a lower WOMAC change score at 1 year (p = 0.01).

Conclusion.

Interventions to improve control over arthritis symptoms should be studied with the goal of improving surgical outcomes.