bluuebunny/crossref_metadata_2025 huggingface dataset:
Cerebral cavernous malformations: clinical insights from genetic studies
Authors: Mindea Stefan A. , Yang Benson P. , Shenkar Robert , Bendok Bernard , Batjer H. Hunt , Awad Issam A.
Published: January 2008

✓ Familial disease is responsible for one third to one half of cerebral cavernous malformation (CCM) cases presenting to clinical attention. Much has been learned in the past decade about the genetics of these cases, which are all inherited in an autosomal dominant pattern, at three known chromosome loci. Unique features of inherited CCMs in Hispanic-Americans of Mexican descent have been described. The respective genes for each locus have been identified and preliminary observations on disease pathways and mechanisms are coming to light, including possible explanations for selectivity of neural milieu and relationships to endothelial layer abnormalities. Mechanisms of lesion genesis in cases of genetic predisposition are being investigated, with evidence to support a two-hit model emerging from somatic mutation screening of the lesions themselves and from lesion formation in transgenic murine models of the disease. Other information on potential inflammatory factors has emerged from differential gene expression studies. Unique phenotypic features of solitary versus familial cases have emerged: different associations with venous developmental anomaly and the exceptionally high penetrance rates that are found in inherited cases when high-sensitivity screening is performed with gradient echo magnetic resonance imaging. This information has changed the landscape of screening and counseling for patients and their families, and promises to lead to the development of new tools for predicting, explaining, and modifying disease behavior.
Review of the literature on de novo formation of cavernous malformations of the central nervous system after radiation therapy
Authors: Nimjee Shahid M. , Powers Ciaran J. , Bulsara Ketan R.
Published: January 2008

✓In this paper the authors review the literature concerning de novo cavernoma formation after radiation treatment. PubMed and MEDLINE database searches were performed. Data were compiled on all patients in whom de novo cavernomas formed after radiation treatment and whose cases were reported in the literature. The authors found reports in the literature of 76 patients in whom cavernomas formed de novo after radiation treatment. The mean age of the patients was 11.7 years, and the majority of these lesions occurred in males. The patients received a mean radiation dose of 60.45 Gy. The mean latency period before detection of the cavernoma was 8.9 years, and most of these lesions were detected incidentally. In symptomatic patients, the most common presenting symptoms were seizures. Thirty-seven of the patients had evidence of hemorrhage, and 54% of these required surgical intervention.

De novo formation of cavernomas after radiation treatment is a relatively rare phenomenon. Patients in whom these cavernomas develop need to be followed closely because there is a propensity for the lesions to hemorrhage. Surgical intervention to treat symptomatic lesions has a favorable outcome.
Drug-resistant temporal lobe epilepsy due to cavernous malformations
Authors: Paolini Sergio , Morace Roberta , Di Gennaro Giancarlo , Picardi Angelo , Grammaldo Liliana G. , Meldolesi Giulio Nicolò , Quarato Pier Paolo , Raco Antonino , Esposito Vincenzo
Published: January 2008

Object

Supratentorial cavernous angiomas may be associated with drug-resistant focal epilepsy. Surgical removal of the malformation may result in seizure control in a number of patients, although in most studies a long history and high frequency of attacks have been recognized as indicators of unfavorable seizure outcome. In the literature, there are no clear indications regarding the optimal diagnostic presurgical workup and the surgical strategy for this particular subgroup of patients with symptomatic epilepsy. In this paper the authors focus on the preoperative workup and the surgical management of the disease in eight consecutive patients undergoing surgery for drug-resistant temporal lobe epilepsy (TLE) due to cavernous malformations (CMs), and the relevant literature on this issue is also reviewed.

Methods

Preoperatively, all patients were assessed using a noninvasive protocol aimed at localizing the epileptogenic zone on the basis of anatomical, electrical, and clinical criteria. The presurgical assessment yielded an indication for lesionectomy in two cases, lesionectomy plus anteromesial temporal lobectomy in four cases, and lesionectomy plus extended temporal lobectomy in two cases. At follow-up examinations, seizure, neuropsychological, and psychiatric outcomes were all evaluated. Seven patients were categorized in Engel Class IA (seizure free), and one was categorized in Engel Class IB (occasional auras only). No adverse effects on neuropsychological or psychosocial functioning were observed.

Conclusions

Epilepsy surgery can be performed with excellent results in patients with intractable TLE caused by CMs. Noninvasive presurgical evaluation of these patients may enable a tailored approach, providing complete seizure relief in most cases.
Intrathecal baclofen therapy in children
Authors: Albright A. Leland , Ferson Susan S.
Published: January 2008

✓ Since its introduction in the late 1980s, intrathecal baclofen (ITB) therapy has become the standard treatment for severe generalized spasticity and dystonia in children. Treatment with ITB decreases spasticity in the upper and lower extremities and has been associated with improved function and decreased musculoskeletal contractures. In addition, ITB decreases generalized secondary dystonia and has been associated with improved comfort and ease of care in approximately 85% and with improved function in approximately 33% of patients. Continued effectiveness of ITB in treating spasticity has been observed for up to 17 years, and its effectiveness in treating dystonia has been observed for up to 10 years. Although ITB therapy is frequently associated with complications such as infections, catheter malfunctions, and cerebrospinal fluid leaks, the benefits of therapy appear to outweigh the risks. Additional investigation is needed to determine the effects of ITB on other movement disorders such as athetosis and chorea.
Surgical techniques of selective dorsal rhizotomy for spastic cerebral palsy
Authors: Park Tae Sung , Johnston James M.
Published: January 2008

✓ Selective dorsal rhizotomy is a well-established surgical procedure for improving lower-extremity spasticity in children with cerebral palsy. The standard technique requires an L1–S1 laminectomy or laminoplasty for visualization of all dorsal nerve roots exiting at their respective foramina. The authors describe a rhizotomy procedure that requires a single-level laminectomy at the level of the conus, with the advantages of decreased operating time and postoperative pain as well as a minimal risk of progressive lumbar instability. This procedure is both effective and well tolerated in appropriately selected children and adults, and has had one cerebrospinal fluid lead requiring operative repair in more than 1500 patients treated at the authors' institution since 1991.
Effect of combined simvastatin and cyclosporine compared with simvastatin alone on cerebral vasospasm after subarachnoid hemorrhage in a canine model
Authors: Bulsara Ketan R. , Coates Joan R. , Agrawal Vivek K. , Eifler Danielle M. , Wagner-Mann Colette C. , Durham H. Edward , Fine Deborah M. , Toft Kris
Published: January 2008

Object

The object of this study was to determine whether the combination of cyclosporine and simvastatin could ameliorate cerebral vasospasm after subarachnoid hemorrhage (SAH) in a canine model to a greater extent than simvastatin alone.

Methods

Animals were assigned to one of three groups: control (five dogs), simvastatin alone (four), or simvastatin and cyclosporine (four). A double SAH model was used. Baseline basilar artery (BA) angiograms were obtained. These were repeated at Days 3, 7, and 10. Measurement of the BA diameter was performed.

Decreased BA diameter was seen on Day 3 in the control and simvastatin/cyclosporine group. A return to baseline diameters was seen by Day 7. An increase from baseline diameter was seen in the simvastatin group at Day 10.

Conclusions

Cyclosporine may interfere with the vasodilatory effects of simvastatin. Vasodilation greater than baseline is seen at Day 10 in the simvastatin group. The combination of simvastatin and cyclosporine does not ameliorate cerebral vasospasm in a canine model to a greater extent than simvastatin alone.
Effect of intraarterial papaverine and/or angioplasty on the cerebral veins in patients with vasospasm after subarachnoid hemorrhage due to ruptured intracranial aneurysms
Authors: Elsayed Ayman A. , Moran Christopher J. , Cross DeWitte T. , Derdeyn Colin P. , Pilgram Thomas K. , Milburn James M. , Dacey Ralph G. , Diringer Michael N.
Published: January 2008

Object

The goal in this study was to determine if there was a change in intracranial venous diameters after endo-vascular treatment of carotid distribution vasospasm caused by subarachnoid hemorrhage.

Methods

The venous diameters were measured in all patients who received intraarterial papaverine and/or balloon angioplasty for treatment of vasospasm during the study period of 3 years. To evaluate the veins of Labbé and Trolard, the straight sinus, and the superior sagittal sinus (SSS), measurements were performed in a blinded manner with the aid of a magnification loupe. Predetermined sites were evaluated on angiograms obtained before and after endovascular treatment. Forty-three treatments in 26 patients were included: 18 patients (33 territories) were treated with intraarterial papaverine alone, four (four territories) were treated with balloon angioplasty alone, and four (six territories) were treated with both papaverine infusion and angioplasty.

The mean measured venous diameters increased significantly after addition of papaverine (10.9%), and also after combined papaverine and angioplasty (4.2%). There was no statistically significant increase in the mean venous diameters after angioplasty alone. If the initial intracranial pressure (ICP) was less than 15 mm Hg before treatment, the veins showed a greater tendency to dilate than if the initial ICP measurements were greater than 15 mm Hg. The straight sinus and the SSS increased more in diameter than the veins of Labbé and Trolard. There was no statistically significant correlation between the change in venous diameters with treatment and ICP.

Conclusions

Endovascular treatment produces measurable increases in intracranial venous diameters. However, these changes do not correlate with changes in ICP.
Lumbar spine injuries in athletes
Authors: Dunn Ian F. , Proctor Mark R. , Day Arthur L.
Published: January 2008

✓Lumbar spine injuries in athletes are not uncommon and usually take the form of a mild muscle strain or sprain. More severe injuries sustained by athletes include disc herniations, spondylolistheses, and various types of fracture. The recognition and management of these injuries in athletes involve the additional consideration that to return to play, the lumbar spine must be able to withstand forces similar to those that were injurious. The authors consider common lumbar spine injuries in athletes and discuss management principles for neurosurgeons that are relevant to this population.
Ocular manifestations and treatment of central nervous system lymphomas
Authors: Gündüz Kaan , Pulido Jose S. , McCannel Colin A. , O'Neill Brian Patrick
Published: January 2008

✓ Intraocular primary central nervous system lymphoma (PCNSL), also called primary intraocular lymphoma (PIOL), is a subset of PCNSL in which lymphoma cells invade the subretinal pigment epithelial space and vitreous cavity with or without central nervous system involvement at the time of ocular diagnosis. The frequency of this rare condition has increased over the past years in immunosuppressed as well as immunocompetent patients. The authors review the current status of PIOL and elaborate on their group's experience with its diagnosis and treatment.

The incidence of PIOL is increasing. There is evidence that chronic antigenic stimulation may result in the development of PIOL. Recent advancements in the diagnosis of PIOL include better handling of vitreous specimens for cytological studies, immunocytological investigation for lymphoid cells, flow cytometry, cytokine evaluation, and molecular analysis. Because PIOL has a nonspecific presentation, the differential diagnosis should include infectious and noninfectious causes presenting with vitreitis and/or subepithelial infiltration as well as paraneoplastic syndromes including CRMP-5 optic neuropathies. Given that therapy is long-term and has significant systemic and ocular complications, tissue diagnosis is important. Treatment of PIOL may include systemic chemotherapy in which high-dose methotrexate-based regimens are used as well as intraocular injections of methotrexate and rituximab (anti-CD20 antibody). Cranial and ocular external-beam radiotherapy is being used less often today.

Further studies are needed to prevent the tumor formation in terms of eliminating antigenic load and inhibiting B-cell chemokines as well as to determine the optimal local and systemic chemotherapy and immunotherapy options in the management of PIOL.
Efficacy of celecoxib in the treatment of CNS lymphomas: an in vivo model
Authors: Wang Weijun , Kardosh Adel , Su Yuzhuang S. , Schonthal Axel H. , Chen Thomas C.
Published: January 2008

Object

The incidence of primary central nervous system lymphomas (PCNSLs) has increased over the past several decades. Unfortunately, even with the most effective therapeutic regimen (that is, methotrexate with whole-brain radiation therapy), PCNSL recurs within a few years in more than half of the treated patients and is eventually fatal. Because PCNSL usually occurs in older patients and in those with acquired immunodeficiency syndrome, combination treatments in which both chemo- and radiation therapy are used is often poorly tolerated and results in a significant reduction in the quality of life. Recently, it has been demonstrated that the selective cyclooxygenase-2 inhibitor celecoxib (Celebrex), can block the growth of lymphoma cells in vitro.

Methods

To create an experimental animal model in vivo for the PCNSL study, the authors intracranially injected a human B-cell lymphoma cell line into nude mice. Their data demonstrate that this experimental model is an excellent one for human PCNSL with brain and leptomeningeal involvement. They also evaluated the feasibility of using celecoxib as a therapeutic agent in the treatment of PCNSL. Nude mice with intracranial lymphomas were treated with celecoxib contained in the animal chow. The treated animals demonstrated significantly prolonged survival times compared with the untreated animals.

Conclusions

Based on the authors' data, celecoxib may be a promising therapeutic agent for the treatment of PCNSL.
Spinal nerve root stimulation
Authors: Haque Raqeeb , Winfree Christopher J.
Published: January 2008

✓Spinal nerve root stimulation is a recently developed form of neuromodulation used for the treatment of chronic pain conditions. Unlike spinal cord stimulation, in which electrical impulses are directed at the dorsal columns, spinal nerve root stimulation guides electrical current directly to one or more nerve roots. There are a variety of techniques by which this can be accomplished, yet no consistent terminology to describe these variations exists. In this review, the authors group the various techniques according to anatomical approach, define each category, describe and illustrate each of the techniques, review the available reports on their uses, and discuss the advantages and disadvantages of each one.
Motor cortex stimulation and neuropathic facial pain
Authors: Henderson Jaimie M. , Lad Shivanand P.
Published: January 2008

✓Trigeminal neuropathic pain is a syndrome of severe, constant facial pain related to disease of or injury to the trigeminal nerve or ganglion. Causes of this type of pain can include injury from sinus or dental surgery, skull and/or facial trauma, or intentional destruction for therapeutic reasons (deafferentation) as well as intrinsic pathological conditions in any part of the trigeminal system. Motor cortex stimulation (MCS) is a relatively new technique that has shown some promise in the treatment of trigeminal neuropathic pain. This technique has the potential to revolutionize the treatment of chronic pain. The authors present a review of the literature, focusing on surgical technique, device programming, safety, and efficacy, and suggest some initial guidelines for standardization of these aspects. It is important to evaluate MCS critically in a prospective, controlled fashion.
Classification of posterior dynamic stabilization devices
Authors: Khoueir Paul , Kim K. Anthony , Wang Michael Y.
Published: January 2008

✓Numerous new posterior dynamic stabilization (PDS) devices have been developed for the treatment of disorders of the lumbar spine. In this report the authors provide a classification scheme for these devices and describe several clinical situations in which the instrumentation may be expected to play a role. By using this classification, the PDSs that are now available and those developed in the future can be uniformly categorized.
Posterior dynamic stabilization of the lumbar spine: pedicle-based stabilization with the AccuFlex rod system
Authors: Mandigo Christopher E. , Sampath Prakash , Kaiser Michael G.
Published: January 2008

✓Posterior dynamic stabilization in the lumbar spine is performed in an attempt to reduce loading across the intervertebral disc for the purpose of relieving pain and limiting degeneration while preserving motion. The AccuFlex rod system (Globus Medical, Inc.), a first-generation device, achieves this by changing the properties of the rod within the Protex pedicle screw–based rigid rod system. Helical cuts that have been created in the standard 6.5-mm rod allow for a limited range of motion while providing a posterior tension band that relieves a significant amount of disc loading. The AccuFlex rod system has been approved by the Food and Drug Administration for single-level fusion when used in conjunction with an interbody graft. In a study involving 170 patients who underwent fusion surgery for back pain, the 54 who received the AccuFlex construct had statistically similar fusion rates and outcomes (as assessed by visual analog scale and Short Form-16 scores) when compared with 116 patients treated with rigid rod fixation after 1 year of follow up. Future clinical studies will examine and provide information regarding the impact of AccuFlex on the incidence of adjacent-level disease. Information gained through the clinical experience with AccuFlex will serve as a foundation for the development of a stand-alone dynamic construct.
Arachnoid cysts: case series and review of the literature
Authors: Pradilla Gustavo , Jallo George
Published: January 2008

Object

Arachnoid cysts are commonly encountered fluid collections in the central nervous system. Recent advances in neuroimaging have translated into an increased detection of these cysts; that is, diagnoses can be made more frequently at earlier stages. Significant advances have also been made in the surgical management of these lesions. The authors report on a case series that illustrates the diverse forms of presentation and the treatment modalities commonly used for arachnoid cysts.

Methods

Between January 2002 and December 2006, 20 patients with arachnoid cysts underwent surgery performed by the senior author at The Johns Hopkins Hospital. Seventy percent of the cysts were supratentorial, 5% infratentorial, and 25% spinal. All diagnoses were confirmed on neuroimaging, surgery, and histological examination. Included in the study were 12 male (60%) and eight female (40%) patients, ranging in age from 2 weeks to 39 years (mean age 10.9 years) at the time of surgery.

Symptoms at presentation included headache (41%), weakness (23%), seizure (14%), hydrocephalus (9%), scoliosis (4%), cognitive decline (4%), and visual loss (4%). Twenty-five percent of the cysts were sylvian, 20% intraventricular, and 20% suprasellar. Supratentorial cysts were treated endoscopically in 73% of patients and with open resection in the remaining 27%. Complications included spasticity, hemiparesis, cerebrospinal fluid leak, hydrocephalus, and subdural hygroma. On follow-up evaluation, 60% of patients had stable cysts and improved symptoms, 13% complete symptom resolution, and 13% stable symptoms.

All patients with spinal cysts underwent laminectomies and fenestration, and one cystosubarachnoid (CS) shunt was placed. Cyst reaccumulation occurred in three patients; two patients required cystoperitoneal (CP) and CS shunts. No deaths occurred.

Conclusions

Most arachnoid cysts are found incidentally and can be managed conservatively. Symptomatic patients are surgical candidates. Treatments include CP shunt placement, craniotomy, or endoscopic fenestration, and stereotactic aspiration. Recent advances in neurosurgical techniques and neuroendoscopy continue to favor fenestration over shunt insertion as the method of choice for initial cyst decompression.
Vascular complications after radiosurgery for meningiomas
Authors: Barami Kaveh , Grow Allison , Brem Steven , Dagnew Elias , Sloan Andrew E.
Published: January 2008

✓During the past 25 years, radiosurgery has evolved as a primary treatment modality for certain meningiomas when resection would be associated with high patient morbidity. In addition, radiosurgery is now routinely used as an adjunctive therapy for residual or recurrent meningiomas after surgical removal. In this review the authors summarize the vascular complications that occur after radiosurgery for meningiomas as well as experimental study data that give insight into the pathogenesis of this complication. These data may be useful when discussing with patients the risk/benefit ratio of choosing among conservative management, radiosurgery, and surgery.
Surgical management of brain metastases
Authors: Ranasinghe Moksha G. , Sheehan Jonas M.
Published: January 2008

✓Metastatic brain tumors continue to increase in incidence as patients with cancer live longer. The options for management continue to evolve as well, with advances in radiation-based treatment, chemotherapy, and surgery. Although metastatic brain tumors are frequently treated without surgical intervention, there continues to be a significant role for surgery in caring for patients with these lesions. Study data have proven that surgery has a positive effect on survival and quality of life in properly selected patients. Those with a suitable age, functional status, systemic disease control, and several metastases may be suitable for surgical treatment. Advances in preoperative imaging and planning as well as intraoperative surgical adjuncts have lowered the morbidity associated with resection. With proper patient selection and operative and postoperative management, resection continues to play a significant and evolving role in the care of patients with metastatic brain tumor.
Radiobiology of brain metastasis: applications in stereotactic radiosurgery
Authors: Jagannathan Jay , Sherman Jonathan H. , Mehta Gautam U. , Chin Lawrence S.
Published: January 2008

✓Stereotactic radiosurgery is a neurosurgical modality in which a target lesion can be irradiated while sparing normal brain tissue. In some respects, brain metastasis is well suited for radiosurgery, as metastatic lesions tend to be small and well circumscribed and displace (but do not infiltrate) normal brain tissue, facilitating the delivery of radiation. Advances in stereotactic radiosurgical planning, such as blocking patterns and beam shaping, have allowed further targeting of discrete lesions while minimizing the effect of radiation toxicity on the central nervous system. In this paper the authors review the radiobiology of brain metastases and stereotactic radiosurgical approaches that can be used to treat these tumors safely.
A rare, delayed complication of a ventriculogallbladder shunt
Authors: Fountas Kostas N. , Kassam Mozaffar A. , Grigorian Arthur A.
Published: January 2008

✓The use of the gallbladder as an alternative cerebrospinal fluid diversion site has been previously described in cases in which all other body cavities, such as the peritoneal cavity, right atrium, or pleural cavity, have been exhausted. Various ventriculogallbladder (VG) shunt complications have been described as well. In the present paper, the authors report on a rare, delayed VG shunt complication. A distal obstruction developed in a previously inserted VG shunt because of a large, radiolucent bile calculus. The presence of the VG shunt could be implicated in the pathogenetic mechanism of the bile calculus formation. The authors also review the pertinent literature.
The history of mathematical modeling in hydrocephalus
Authors: Clarke Michelle J. , Meyer Fredric B.
Published: January 2008

✓The mathematical modeling of hydrocephalus is a relatively young field. The discipline evolved from Hakim's initial description of the brain as a water-filled sponge. Nagashima and colleagues subsequently translated this description into a computer-driven model by defining five important system rules. A number of researchers have since criticized and refined the method, providing additional system constraints or alternative approaches. Such efforts have led to an increased understanding of ventricular shape change and the development of periventricular lucency on imaging studies. However, severe limitations exist, precluding the use of the mathematical model to influence the operative decisions of practicing surgeons. In this paper, the authors explore the history, limitations, and future of the mathematical model of hydrocephalus.
Role of edema in peritumoral cyst formation
Authors: Baggenstos Martin A. , Butman John A. , Oldfield Edward H. , Lonser Russell R.
Published: January 2008

✓Peritumoral cysts (those arising immediately adjacent to the tumor mass) are frequently associated with benign and malignant tumors of the brain and spinal cord (syringomyelia). The cystic component of central nervous system (CNS) tumors and associated peritumoral cysts are often the cause of clinical symptoms. Because of the common occurrence of peritumoral cysts with CNS neoplasms and the morbidity associated with them, advanced imaging, histological, and molecular techniques have been used to determine the mechanism underlying cyst formation and propagation. Based on evidence from such studies, edema appears to be a common precursor to peritumoral cyst formation in the CNS. Mediators of vascular permeability acting locally in the tumor and/or hydrodynamic forces within abnormal tumor vascula-ture appear to drive fluid extravasation. When these forces overcome the ability of surrounding tissue to resorb fluid, edema and subsequent cyst formation occur. These findings support the concept that the tumor itself is the source of the edema that precedes cyst formation and that resection of tumors or medical therapies directed at decreasing their vascular permeability will result in the resolution of edema and cysts.
Preconditioning with hyperbaric oxygen attenuates brain edema after experimental intracerebral hemorrhage
Authors: Qin Zhiyong , Song Shuijiang , Xi Guohua , Silbergleit Robert , Keep Richard F. , Hoff Julian T. , Hua Ya
Published: January 2008

Object

Preconditioning with hyperbaric oxygen (HBO2) reduces ischemic brain damage. Activation of p44/42 mitogen-activated protein kinases (p44/42 MAPK) has been associated with preconditioning-induced brain ischemic tolerance. This study investigated if preconditioning with HBO2 protects against intracerebral hemorrhage (ICH)–induced brain edema formation and examined the role of p44/42 MAPK in such protection.

Methods

The study had three experimental groups. In Group 1, Sprague-Dawley rats received two, three, or five consecutive sessions of preconditioning with HBO2 (3 ata, 100% xygen, 1 hour daily). Twenty-four hours after preconditioning with HBO2, rats received an infusion of autologous blood into the caudate. They were killed 1 or 3 days later for brain edema measurement. Rats in Group 2 received either five sessions of preconditioning with HBO2 or control pretreatment and were killed 24 hours later for Western blot and immunohistochemical analyses. In Group 3, rats received an intracau-date injection of PD098059 (an inhibitor of p44/42 MAPK activation) before the first of five sessions of preconditioning with HBO2. Twenty-four hours after the final preconditioning with HBO2, rats received an intracaudate blood infusion. Brain water content was measured 24 hours after ICH.

Results

Fewer than five sessions of preconditioning with HBO2 did not significantly attenuate brain edema after ICH. Five sessions of preconditioning with HBO2 reduced perihematomal edema 24 and 72 hours after ICH (p < 0.05). Strong p44/42 MAPK immunoreactivity was detected in the basal ganglia 24 hours after preconditioning with BO2. Intracaudate infusion of PD098059 abolished HBO2preconditioning–induced protection against ICH-induced brain edema formation.

Conclusions

Preconditioning with HBO2 protects against brain edema formation following ICH. Activation of the p44/42 MAPK pathway contributes to that protection. Preconditioning with HBO2 may be a way of limiting brain injury during invasive neurosurgical procedures that cause bleeding.
Surgical management of malignant peripheral nerve sheath tumors
Authors: Gachiani John , Kim Daniel , Nelson Adriane , Kline David
Published: January 2008

Object

The aim of this study was to describe the presentation of patients harboring soft tissue sarcomas involving the nerves, most of which were malignant peripheral nerve sheath tumors (MPNSTs), and provide an algorithm for their treatment.

Methods

The authors retrospectively analyzed data on 43 surgically treated soft tissue sarcomas involving the nerves, 34 (79%) of which were MPNSTs. Tumor classifications are presented, together with patient numbers, locations of MPNSTs, surgical techniques, and adjunctive treatments.

Results

The 34 MPNSTs were surgically treated during a period of 40 years. Most of these lesions (19 MPNSTs [56%]) were located in the brachial plexus, whereas the rest were located on other major nerves. Neurofibromatosis Type 1–associated tumors (12 lesions) represented 35% of the total number of MPNSTs. Although the main goal of surgery was complete excision, it was successful in only 16 patients (47%). Of the available records, 18 patients (53%) died due to disease progression.

Conclusions

Malignant peripheral nerve sheath tumors are rare. Surgical removal with margins when possible coupled by adjuvant radiotherapy offers the best chance of survival. The role of chemotherapy is still being defined.
Granular cell tumor: a rare tumor of the ulnar nerve
Authors: Davis Gavin A.
Published: January 2008

✓Granular cell tumors of the ulnar nerve are extremely rare, with only two cases previously reported in the English literature. The author presents a case of granular cell tumor of the ulnar nerve, in which the tumor was resected and the nerve was repaired with a nerve graft. The histopathological characteristics, imaging findings, and clinical data regarding these tumors are reviewed, and based on all the available evidence, a new treatment paradigm is proposed, which differs from that used in the earlier reported cases and takes into account the reported rate of tumor recurrence after incomplete resection.
Diagnostic approach to Cushing disease
Authors: Gross Bradley A. , Mindea Stefan A. , Pick Anthony J. , Chandler James P. , Batjer H. Hunt
Published: January 2008

✓ In Cushing disease, a pituitary corticotroph neoplasm causes secondary adrenal hypercortisolism. This condition has known morbidity and mortality, underscoring the need for an efficient and accurate diagnostic approach. An 11 p.m. salivary cortisol level is a modern, simple initial screening tool for the diagnosis of Cushing syndrome. Confirmation with a 24-hour urinary free cortisol test and/or a low-dose dexamethasone suppression test may subsequently be performed. Patients with repeatedly equivocal results should be reevaluated after several months or undergo a corticotropin-releasing hormone (CRH) stimulation test following low-dose dexamethasone suppression to help rule out pseudo-Cushing states. The presence of low morning serum adrenocorticotropic hormone (ACTH) levels then distinguishes primary adrenal hypercortisolism from Cushing disease and the ectopic ACTH syndrome. Patients with moderate ACTH levels can undergo CRH stimulation testing to clarify the underlying disease because those with an ACTH-independent disorder have blunted subsequent ACTH levels. Once ACTH-dependent hypercortisolemia is detected, magnetic resonance (MR) imaging of the pituitary gland can be performed to detect a pituitary neoplasm. Normal or equivocal MR imaging results revealing small pituitary lesions should be followed up with inferior petrosal sinus sampling, a highly specific measure for the diagnosis of Cushing disease in experienced hands. If necessary, body imaging may be used in turn to detect sources of ectopic ACTH.
Gamma Knife surgery for neurocytoma
Authors: Yen Chun Po , Sheehan Jason , Patterson Greg , Steiner Ladislau
Published: January 2008

Object

Although considered benign tumors, neurocytomas have various biological behaviors, histological patterns, and clinical courses. In the last 15 years, fractionated radiotherapy and radiosurgery in addition to microsurgery have been used in their management. In this study, the authors present their experience using Gamma Knife surgery (GKS) in the treatment of these tumors.

Methods

Between 1989 and 2004, the authors performed GKS in seven patients with a total of nine neurocytomas. Three patients harbored five recurrent tumors after a gross-total resection, three had progression of previous partially resected tumors, and one had undergone a tumor biopsy only. The mean tumor volume at the time of GKS ranged from 1.4 to 19.8 cm3 (mean 6.0 cm3). A mean peripheral dose of 16 Gy was prescribed to the tumor margin with the median isodose configuration of 32.5%.

Results

After a mean follow-up period of 60 months, four of the nine tumors treated disappeared and four shrank significantly. Because of secondary hemorrhage, an accurate tumor volume could not be determined in one. Four patients were asymptomatic during the follow-up period, and the condition of the patient who had residual hemiparesis from a previous transcortical resection of the tumor was stable. Additionally, the patient who experienced tumor hemorrhage required a shunt revision, and another patient died of sepsis due to a shunt infection.

Conclusions

Based on this limited experience, GKS seems to be an appropriate management alternative. It offers control over the tumor with the benefits of minimal invasiveness and low morbidity rates. Recurrence, however, is not unusual following both microsurgery and GKS. Open-ended follow-up imaging is required to detect early recurrence and determine the need for retreatment.
Blood flow disturbance in perforating arteries attributable to aneurysm surgery
Authors: Sasaki Tatsuya , Kodama Namio , Matsumoto Masato , Suzuki Kyouichi , Konno Yutaka , Sakuma Jun , Endo Yuji , Oinuma Masahiro
Published: January 2008

Object

The object of this study was to investigate patients with cerebral infarction in the area of the perforating arteries after aneurysm surgery.

Methods

The authors studied the incidence of cerebral infarction in 1043 patients using computed tomography or magnetic resonance imaging and the affected perforating arteries, clinical symptoms, prognosis, and operative maneuvers resulting in blood flow disturbance.

Results

Among 46 patients (4.4%) with infarction, the affected perforating arteries were the anterior choroidal artery (AChA) in nine patients, lenticulostriate artery (LSA) in nine patients, hypothalamic artery in two patients, posterior thalamoperforating artery in five patients, perforating artery of the vertebral artery (VA) in three patients, anterior thalamoperforating artery in nine patients, and recurrent artery of Heubner in nine patients. Sequelae persisted in 21 (45.7%) of the 46 patients; 13 (28.3%) had transient symptoms and 12 (26.1%) were asymptomatic. Sequelae developed in all patients with infarctions in perforating arteries in the area of the AChA, hypothalamic artery, or perforating artery of the VA; in four of five patients with posterior thalamoperforating artery involvement; and in two of nine with LSA involvement. The symptoms of anterior thalamoperforating artery infarction or recurrent artery of Heubner infarction were mild and/or transient. The operative maneuvers leading to blood flow disturbance in perforating arteries were aneurysmal neck clipping in 21 patients, temporary occlusion of the parent artery in nine patients, direct injury in seven patients, retraction in five patients, and trapping of the parent artery in four patients.

Conclusions

The patency of the perforating artery cannot be determined by intraoperative microscopic inspection. Intraoperative motor evoked potential monitoring contributed to the detection of blood flow disturbance in the territory of the AChA and LSA.
Antivasospastic and antiinflammatory effects of caspase inhibitor in experimental subarachnoid hemorrhage
Authors: Iseda Keiichi , Ono Shigeki , Onoda Keisuke , Satoh Motoyoshi , Manabe Hiroaki , Nishiguchi Mitsuhisa , Takahashi Kenji , Tokunaga Koji , sugiu Kenji , Date Isao
Published: January 2008

Object

Inflammation in the subarachnoid space and apoptosis of arterial endothelial cells have been implicated in the development of delayed cerebral vasospasm after subarachnoid hemorrhage (SAH). The authors investigated mechanisms of possible antivasospastic effects of N-benzyl-oxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK), a caspase inhibitor that can inhibit both inflammatory and apoptotic systems, in animal models of SAH.

Methods

Rabbits were assigned to three groups of eight animals each and were subjected to SAH by injection of blood into the cisterna magna. The experiments were performed in the following groups: SAH only, SAH + vehicle, and SAH + Z-VAD-FMK. The Z-VAD-FMK (1 mg) or vehicle (5% dimethyl sulfoxide) was intrathecally administered before SAH induction. Diameters of the basilar artery (BA) were measured on angiograms obtained before and 2 days after SAH. The BA diameter on Day 2 was expressed as a percentage of that before SAH. Interleukin (IL)–1β in the cerebrospinal fluid (CSF) was examined using Western blotting, and brains were immunohistochemically examined for caspase-1 and IL-1β. In a separate experiment, 20 rats were subjected to SAH and their brains were immunohisto-chemically assessed for caspase-1, IL-1β, and macrophages.

Results

In rabbits, Z-VAD-FMK significantly attenuated cerebral vasospasm (the BA diameter on Day 2 in SAH-only, SAH + vehicle, and SAH + Z-VAD-FMK groups was 66.6 ± 3.2%, 66.3 ± 3.7%, and 82.6 ± 4.9% of baseline, respectively), and suppressed IL-1β release into the CSF and also suppressed immunoreactivities of caspase-1 and IL-1β in macrophages infiltrating into the subarachnoid space. Immunoreactivities for caspase-1 and IL-1β were observed in immunohistochemically proven infiltrating macrophages in rats.

Conclusions

These results indicate that caspase activation may be involved in the development of SAH-induced vasospasm through inflammatory reaction.
Axillary nerve repair by triceps motor branch transfer through an axillary access: anatomical basis and clinical results
Authors: Bertelli Jayme Augusto , Kechele Paulo Roberto , Santos Marcos Antonio , Duarte Hamilton , Ghizoni Marcos Flávio
Published: January 2008

Object

Grafting or nerve transfers to the axillary nerve have been performed using a deltopectoral approach and/or a posterior arm approach. In this report, the surgical anatomy of the axillary nerve was studied with the goal of repairing the nerve through an axillary access.

Methods

The axillary nerve was bilaterally dissected in 10 embalmed cadavers to study its variations. Three patients with axillary nerve injuries then underwent surgical repair through an axillary access; the axillary nerve was repaired by transfer of the triceps long head motor branch.

Results

At the lateral margin of the subscapularis muscle, the axillary nerve was found in the center of a triangle bounded medially by the subscapular artery, laterally by the latissimus dorsi tendon, and cephalad by the posterior circumflex humeral artery. At the entrance of the quadrangular space, the axillary nerve divisions were loosely connected to each other, and could be clearly separated and correctly identified. Surgery for the axillary nerve repair through the axillary access was straightforward. Eighteen months after surgery, all three patients had recovered deltoid strength to a score of M4 on the Medical Research Council scale and had improved abduction strength by 50%. No deficit was evident in elbow extension.

Conclusions

The axillary nerve and its branches can be safely dissected and repaired by triceps motor nerve transfer through an axillary access.
Accuracy of ventriculostomy catheter placement using a head- and hand-tracked high-resolution virtual reality simulator with haptic feedback
Authors: Banerjee P. Pat , Luciano Cristian J. , Lemole G. Michael , Charbel Fady T. , Oh Michael Y.
Published: January 2008

Object

The purpose of this study was to evaluate the accuracy of ventriculostomy catheter placement on a head- and hand-tracked high-resolution and high-performance virtual reality and haptic technology workstation.

Methods

Seventy-eight fellows and residents performed simulated ventriculostomy catheter placement on an ImmersiveTouch system. The virtual catheter was placed into a virtual patient's head derived from a computed tomography data set. Participants were allowed one attempt each. The distance from the tip of the catheter to the Monro foramen was measured.

Results

The mean distance (± standard deviation) from the final position of the catheter tip to the Monro foramen was 16.09 mm (± 7.85 mm).

Conclusions

The accuracy of virtual ventriculostomy catheter placement achieved by participants using the simulator is comparable to the accuracy reported in a recent retrospective evaluation of free-hand ventriculostomy placements in which the mean distance from the catheter tip to the Monro foramen was 16 mm (± 9.6 mm).
Reduction of intractable deafferentation pain due to spinal cord or peripheral lesion by high-frequency repetitive transcranial magnetic stimulation of the primary motor cortex
Authors: Saitoh Youichi , Hirayama Azuma , Kishima Haruhiko , Shimokawa Toshio , Oshino Satoru , Hirata Masayuki , Tani Naoki , Kato Amami , Yoshimine Toshiki
Published: January 2008

Object

The authors previously reported that navigation-guided repetitive transcranial magnetic stimulation (rTMS) of the precentral gyrus relieves deafferentation pain. Stimulation parameters were 10 trains of 10-second 5-Hz TMS pulses at 50-second intervals. In the present study, they used various stimulation frequencies and compared efficacies between two types of lesions.

Methods

Patients were divided into two groups: those with a cerebral lesion and those with a noncerebral lesion. The rTMS was applied to all the patients at frequencies of 1, 5, and 10 Hz and as a sham procedure in random order. The effect of rTMS on pain was rated by patients using a visual analog scale.

Results

The rTMS at frequencies of 5 and 10 Hz, compared with sham stimulation, significantly reduced pain, and the pain reduction continued for 180 minutes. A stimulation frequency of 10 Hz may be more effective than 5 Hz, and at 1 Hz was ineffective. The effect of rTMS at frequencies of 5 and 10 Hz was greater in patients with a noncerebral lesion than those with a cerebral lesion.

Conclusions

High-frequency (5- or 10-Hz) rTMS of the precentral gyrus can reduce intractable deafferentation pain, but low-frequency stimulation (at 1 Hz) cannot. Patients with a noncerebral lesion are more suitable candidates for high-frequency rTMS of the precentral gyrus.
Influence of light fluence rate on the effects of photodynamic therapy in an orthotopic rat glioma model
Authors: Angell-Petersen Even , Spetalen Signe , Madsen Steen J. , Sun Chung-Ho , Peng Qian , Carper Stephen W. , Sioud Mouldy , Hirschberg Henry
Published: January 2008

Object

Failure of treatment for high-grade gliomas is usually due to local recurrence at the site of resection, indicating that a more aggressive local therapy could be beneficial. Photodynamic therapy (PDT) is a local treatment involving the administration of a tumor-localizing photosensitizing drug, in this case aminolevulinic acid (ALA). The effect depends on the total light energy delivered to the target tissue, but may also be influenced by the rate of light delivery.

Methods

In vitro experiments showed that the sensitivity to ALA PDT of BT4C multicellular tumor spheroids depended on the rate of light delivery (fluence rate). The BT4C tumors were established intracranially in BD-IX rats. Microfluorometry of frozen tissue sections showed that photosensitization is produced with better than 200:1 tumor/normal tissue selectivity after ALA injection. Four hours after intraperitoneal ALA injection (125 mg/kg), 26 J of 632 nm light was delivered interstitially over 15 (high fluence rate) or 90 (low fluence rate) minutes. Histological examination of animals treated 14 days after tumor induction demonstrated extensive tumor necrosis after low-fluence-rate PDT, but hardly any necrosis after high-fluence-rate treatment. Neutrophil infiltration in tumor tissue was increased by PDT, but was similar for both treatment regimens. Low-fluence-rate PDT administered 9 days after tumor induction resulted in statistically significant prolongation of survival for treated rats compared with nontreated control animals.

Conclusions

Treatment with ALA PDT induced pronounced necrosis in tumors only if the light was delivered at a low rate. The treatment prolonged the survival for tumor-bearing animals.