bluuebunny/crossref_metadata_2025 huggingface dataset:
Predicting outcome following surgical treatment of unruptured intracranial aneurysms: a proposed grading system
Authors: Khanna Rohit K. , Malik Ghaus M. , Qureshi Nuzhat
Published: June 2009

✓ Surgical treatment of unruptured aneurysms is gaining increased support owing to the recently defined poor long-term natural history of these aneurysms. The benefit of treatment ultimately depends on the relative risk of subsequent aneurysm rupture in untreated patients versus the risk of surgery. To identify those patients at a higher risk from surgery, the authors reviewed the management of 172 patients with unruptured intracranial aneurysms treated at their institution. The size of the aneurysms ranged from 3 to 45 mm (mean 13.7 mm). Twenty-two patients (12.8%) had aneurysms in the posterior circulation, and 32 (18.6%) of these were giant aneurysms. Major morbidity occurred in 12 patients (6.9%) and five patients (2.9%) died. Multivariate logistic analysis of several risk factors revealed that aneurysm size and location had an independent correlation with surgical outcome and that patient age approached statistical significance. Patients presenting with ischemic cerebrovascular disease, in particular, did not have a higher risk of a poor outcome.

A simple classification for predicting patients at high risk from surgical morbidity and mortality is proposed. Preoperative grading is based on the size and location of the aneurysm and patient's age. The lowest grade is given to young patients with small anterior circulation aneurysms, and the highest grade includes elderly patients with complex giant posterior circulation aneurysms. A retrospective analysis of this classification demonstrated a strong correlation with postoperative outcome. The incidence of poor outcome progressively increased with a higher grade, ranging from 0% in Grade 0 to 66.6% in Grade VI. An analysis of this classification on 50 consecutive surgically treated patients with unruptured aneurysms not included in the analysis also validated the predictive value of this system. Along with predicting outcome, this classification should provide a standardized format for comparison of results from different clinical centers as well as different therapeutic techniques (surgical vs. endovascular) without omission of significant risk factors found to influence outcome.
Treatment of large and giant fusiform intracranial aneurysms with Guglielmi detachable coils
Authors: Gobin Y. Pierre , Viñuela Fernando , Gurian John H. , Guglielmi Guido , Duckwiler Gary R. , Massoud Tarik F. , Martin Neil A.
Published: June 2009

✓ Results in nine patients with large or giant fusiform intracranial aneurysms that were treated with Guglielmi detachable coils (GDCs) are reported. There were six males and three females between the ages of 12 and 63. Four patients presented with subarachnoid hemorrhage (SAH) and four with mass effect; in one patient the aneurysm was asymptomatic and located in an arterial feeder of an arteriovenous malformation. Five aneurysms were supratentorial and four were in the posterior fossa. Five were giant and four were large. Selective occlusion with preservation of the parent artery was attempted in three cases, and complete occlusion of the aneurysm and the parent artery was performed in six patients. The tolerance to parent artery occlusion was assessed by angiography, balloon test occlusion, and amytal testing. Six aneurysms were permanently occluded and two partially recanalized. In one case, GDC embolization was not possible.

The four patients who presented with SAH made an excellent clinical recovery. Three of the four patients presenting with mass effect recovered completely and one remained unchanged. The patient with an incidental aneurysm remained asymptomatic. There were no permanent complications. In conclusion, GDCs were useful for the occlusion of large and giant intradural fusiform aneurysms. Occlusion of the aneurysm and the parent artery afforded the greatest opportunity for a complete cure. Advantages of GDCs compared to balloons include: occlusion of a shorter segment of normal artery, no traction on the parent vessel, and safer and easier catheterization techniques.
Intraoperative endovascular surgery for cerebral aneurysms
Authors: Sinson Grant , Philips Matthew F. , Flamm Eugene S.
Published: June 2009

✓ The application of a number of procedures that can be considered intraoperative endovascular neurosurgery has enhanced our ability to treat cerebral aneurysms from the abluminal surface. This study identifies a role for these techniques in the management of difficult aneurysms. A review of the last 1202 aneurysms undergoing direct clipping by the authors disclosed that these methods were used in 62 cases. Of these aneurysms, 36 arose from the internal carotid artery, 12 from the middle cerebral artery, eight from the vertebrobasilar distribution, and six from the anterior cerebral artery.

The indications for applying these methods were large size (12–60 mm), intraluminal thrombus, broad neck, plaque at the neck, the potential compromise of branches at the base of the aneurysm, or a combination of these problems. The most frequently chosen intraoperative technique was suction decompression with direct removal of plaque and thrombus using suction, dissection, and/or ultrasonic aspiration. The application of temporary clips was required in all cases in which the aneurysm was opened before definitive clipping. No special pharmacological cerebral protective regimen was used. In one case in which a greater occlusion time was anticipated, cardiopulmonary bypass with profound hypothermia was performed.

A favorable outcome was achieved in 73% of these difficult cases. An increased neurological deficit after surgery was seen in 11%, and the mortality rate was 8%. These methods should be considered and can be anticipated before surgery for unusual aneurysms. Many cases now being considered for embolization may be more suitable for definitive surgical obliteration.
Relationship between transcranial Doppler-determined pulsatility index and cerebrovascular resistance: an experimental study
Authors: Czosnyka Marek , Richards Hugh K. , Whitehouse Helen E. , Pickard John D.
Published: June 2009

✓ Clinical studies with transcranial Doppler suggest that the pulsatility of the flow velocity (FV) waveform increases when the distal cerebrovascular resistance (CVR) increases. To clarify this relationship, the authors studied animal models in which the resistance may be decreased in a controlled manner by an increase in arterial CO2 tension, or by a decrease in cerebral perfusion pressure (CPP) in autoregulating animals. Twelve New Zealand white rabbits were anesthetized, paralyzed, and ventilated. Transcranial Doppler basilar artery FV, laser Doppler cortical blood flow, arterial pressure, intracranial pressure, and end-tidal CO2 concentration were measured continuously. Cerebrovascular resistance (CPP divided by laser Doppler cortical flux) and Gosling Pulsatility Index (PI, defined as an FV pulse amplitude divided by a timed average FV) were calculated as time-dependent variables for each animal.

Four groups of animals undergoing controlled manipulations of CVR were analyzed. In Group I, arterial CO2 concentration was changed gradually from hypocapnia to hypercapnia. In Group II, gradual hemorrhagic hypotension was used to reduce CPP. In Group III, the short-acting ganglion blocking drug trimetaphan was injected intravenously to induce transient hypotension. Intracranial hypertension was produced by subarachnoid saline infusion in Group IV. During the hypercapnic challenge the correlation between the cortical resistance and Doppler flow pulsatility was positive (r = 0.77, p < 0.001). In all three groups in which cerebral perfusion pressure was reduced a negative correlation between pulsatility index and cerebrovascular resistance was found (r = −20.84, p < 0.001). The authors conclude that PI cannot be interpreted simply as an index of CVR in all circumstances.
Significance of proliferating cell nuclear antigen in predicting recurrence of intracranial meningioma
Authors: Cobb Mark A. , Husain Muhammad , Andersen Bruce J. , Al-Mefty Ossama
Published: June 2009

✓ It is well known that the histological appearance of meningiomas often fails to predict accurately the clinical behavior of the tumor. Therefore, attention has turned from tumor histology to tumor biology. Proliferating cell nuclear antigen (PCNA), a cell cycle-regulated protein, has been recently characterized as the cofactor of DNA polymerase-δ, an enzyme required for DNA replication. The rate of synthesis of PCNA directly correlates with the proliferative state of cells. Immunohistochemical labeling of this antigen is now possible with monoclonal antibodies that allow for its demonstration in routinely fixed, paraffin-embedded specimens.

In this study, the PCNA labeling index (LI) was determined for 83 meningiomas, including tumors with both benign and malignant clinical courses and with benign, atypical, and malignant histologies, apparent after total or subtotal resections. No statistical difference was found between the LI on recurrence and that found at initial presentation. In addition, stepwise multivariate regression analysis failed to identify any combination of factors (age, gender, race, age of specimen, tumor histology, Simpson grade of resection) that contributes to the predictive strength of the PCNA LI for tumor recurrence.

However, for LIs less than 2%, only one of 26 gross totally resected tumors recurred (mean follow up 53 months); for LIs more than 7%, five of 13 gross totally resected tumors recurred (mean follow up 55 months). The difference in recurrence rates between gross totally resected meningiomas with PCNA LIs less than 2% and those with PCNA LIs more than 7% achieved statistical significance with a Fisher's exact probability equaling 0.011. The authors conclude that quantitative PCNA labeling of meningiomas is a promising technique that can provide meaningful prognostic information.
Edema from intracerebral hemorrhage: the role of thrombin
Authors: Lee Kevin R. , Colon Gary P. , Betz A. Lorris , Keep Richard F. , Kim Seoung , Hoff Julian T.
Published: June 2009

✓ The mechanism by which intracerebral hemorrhage leads to the formation of brain edema is unknown. This study assesses the components of blood to determine if any are toxic to surrounding brain. Various solutions were infused stereotactically into the right basal ganglia of rats. The animals were sacrificed 24 hours later; brain edema and ion contents were measured. Whole blood caused an increase in brain water content and ion changes consistent with brain edema. Concentrated blood cells, serum from clotted blood, and plasma from unclotted blood all failed to provoke edema formation when infused directly into the brain. On the other hand, activation of the coagulation cascade by adding prothrombinase to plasma did produce brain edema. The edema response to whole blood could be prevented by adding a specific thrombin inhibitor, hirudin, to the injected blood. This study indicates that thrombin plays an important role in edema formation from an intracerebral blood clot.
A hybrid clinical—research depth electrode for acute and chronic in vivo microelectrode recording of human brain neurons
Authors: Howard Matthew A. , Volkov Igor O. , Granner Mark A. , Damasio Hanna M. , Ollendieck Michael C. , Bakken Hans E.
Published: June 2009

✓ For several decades, important scientific information has been gained from in vivo microelectrode recordings of individual human cerebral cortical neurons in patients with epilepsy. The experimental methods used, however, are technically complex and require a highly skilled intraoperative team. There are also significant experimental time limitations, as well as constraints on the type of behavioral tests conducted, and the brain regions that may be safely studied. In this report, a new method is described for obtaining in vivo microelectrode recordings using a hybrid depth electrode (HDE). High-impedance research recording contacts are interspersed between low-impedance clinical electroencephalographic (EEG) contacts along the HDE shaft. The HDE has the same external physical properties as a standard clinical depth electrode (DE). Following preclinical laboratory testing, 15 HDEs were used in the evaluation of six patients with medically refractory epilepsy. High-quality EEG recordings were obtained in all cases (two acute intraoperative, four from the chronic epilepsy monitoring unit). Action potentials from individual neurons were successfully recorded during all experimental sessions; however, the chronic preparations were clearly superior. Chronic HDEs are placed using a standard stereotactic system, and the locations of recording contacts are documented on a postimplantation imaging study. The quality of the chronic research recordings was excellent over study periods ranging from 5 to 14 days. The patients rested comfortably on the ward and were able to cooperate with complex experimental instructions. Basic neuroscientists participated fully in all aspects of the chronic investigations. The use of an HDE in place of a standard clinical DE may now allow detailed physiological investigations of any brain region targeted for clinical DE implantation.
William Macewen and the treatment of brain abscesses: revisited after one hundred years
Authors: Canale Dee J.
Published: June 2009

✓ The year 1993 marked the centennial of the publication of Sir William Macewen's monograph, Pyogenic Infective Diseases of the Brain and Spinal Cord, and its accompanying volume, Atlas of Head Sections. As Harvey Cushing noted, the text on pyogenic diseases of the brain was a landmark in surgery of the nervous system. At the time of its publication, Macewen's work was the most comprehensive study of pyogenic brain diseases.

In this paper the author reviews the state of knowledge of brain abscess existing in the 19th and 20th centuries, with particular emphasis on the late 19th century, and elucidates factors contributing to Macewen's remarkable success. His thorough knowledge of the natural history of pyogenic diseases of the temporal bone and nasal sinuses, in addition to his clear description of cranial anatomy, as illustrated in his Atlas of Head Sections, were especially important in developing his successful treatment of brain abscess. The x-ray had not yet been discovered; Macewen's diagnosis was based on clinical findings superbly illustrated by his three clinical stages of brain abscess development. His clinical observations are as relevant today as when he described them 100 years ago.

Macewen recorded 25 cases of brain abscess. Nineteen of these patients came to his attention in time to undergo surgery, resulting in 18 recoveries. All five of his patients with extradural abscess recovered. These results were achieved in the era known as “the most glorious period in British surgery.” Neurosurgery was in its infancy; nevertheless, even as the 20th century closes, Macewen's results still have not been surpassed.
Early postoperative magnetic resonance imaging following nonneoplastic cortical resection
Authors: Henegar Martin M. , Moran Christopher J. , Silbergeld Daniel L.
Published: June 2009

✓ Postcraniotomy residual tumor is often determined by magnetic resonance (MR) imaging. Magnetic resonance changes that occur in the postoperative setting must be defined to ensure both the optimum timing of postoperative image acquisition and the accurate assessment of images for residual tumor. Postoperative changes in nontumor parenchyma have previously been described for computerized tomography but not for MR imaging. In the present study, 11 patients without intracranial neoplastic disease (six females and five males with a median age of 36 years) submitted to MR imaging 17 to 28 hours after undergoing temporal lobectomies for epilepsy. Four of the operations were performed with the patients under general anesthesia and seven under local anesthesia. Postoperative MR images (T1-weighted, T1-weighted gadolinium enhanced, and T2-weighted) were reviewed. Extraaxial fluid, air, or blood was present in all cases. Enhancement of the resection bed parenchyma occurred in seven (64%) of 11 patients. In three of the remaining four patients, assessment of parenchymal enhancement was obscured by extraaxial fluid collections. Dural enhancement occurred adjacent to the resection site in all of the cases and remotely in 73%. Eight (73%) of 11 patients displayed enhancement of the pia-arachnoid of the ipsilateral cerebral convexity, two (18%) of the contralateral convexity, and four (36%) of the pia-arachnoid overlying the cerebellum. Contrary to previous reports, contrast enhancement of nonneoplastic human brain parenchyma can occur postoperatively within 17 hours. Benign parenchymal contrast enhancement is usually linear in appearance; non-neoplastic dural and leptomeningeal enhancement can occur both adjacent to and distant from the surgical site. Extraaxial fluid collections can hinder MR evaluation of the resection bed.
Characteristics and surgical treatment of dolichoectatic and fusiform aneurysms
Authors: Anson John A. , Lawton Michael T. , Spetzler Robert F.
Published: June 2009

✓ Dolichoectatic and fusiform aneurysms represent a small subset of cerebral aneurysms and are often among the most difficult to treat. A consecutive series of 40 patients with 41 of these two types of aneurysms is presented, including their clinical characteristics and surgical treatments. Common to all aneurysms was the pathological involvement of a length of blood vessel with separate inflow and outflow sites (nonsaccular). However, dolichoectatic aneurysms have markedly different symptoms and surgical treatments depending on their location in either the anterior or posterior circulation. Anterior circulation aneurysms involved the petrous internal carotid artery (ICA) in one, the supraclinoid ICA in three, the middle cerebral artery in 13, and the anterior cerebral artery in four patients. Posterior circulation aneurysms involved the basilar artery in 13, the vertebral artery in six, and the posterior inferior cerebellar artery in one patient. Various surgical procedures were performed, including direct clipping, trapping with bypass, proximal occlusion, resection with reanastomosis, transposition, aneurysmorrhaphy with thrombectomy, and wrapping. There was no surgical mortality in the patient series, and treatment was effective in many patients. Overall, outcome at late follow up was good (Glasgow Outcome Scale scores 1–2) in 78% of patients. Patients with anterior circulation aneurysms had better outcomes than patients with posterior circulation aneurysms, with good outcomes in 90% and 65% of the cases, respectively. Dolichoectatic and giant serpentine aneurysms may develop from smaller fusiform aneurysms and represent a spectrum of the same pathological entity. Arterial dissection may also play a role in the initial development of these aneurysms.
Methods for microelectrode-guided posteroventral pallidotomy
Authors: Lozano Andres , Hutchison William , Kiss Zelma , Tasker Ronald , Davis Karen , Dostrovsky Jonathan
Published: June 2009

✓ Methods for localizing the posteroventral globus pallidus internus are described. The authors' techniques include the use of microelectrodes to record single-unit activity and to microstimulate in human pallidum and its surrounding structures. This technique allows a precise determination of the locations of characteristic cell types in sequential trajectories through the external and internal segments of the pallidum. The location of the optic tract can be determined from microstimulation-evoked visual sensations and recordings of flash-evoked potentials. In addition, microstimulation-evoked motor and sensory responses allow the internal capsule to be identified. The data collected using this technique are an important adjunct to selecting optimum sites to place electrocoagulation lesions for stereotactic posteroventral pallidotomy for refractory Parkinson's disease.
Chronic electrical stimulation of the ventralis intermedius nucleus of the thalamus as a treatment of movement disorders
Authors: Benabid Alim Louis , Pollak Pierre , Gao Dongming , Hoffmann Dominique , Limousin Patricia , Gay Emmanuel , Payen Isabelle , Benazzouz Abdhelhamid
Published: June 2009

✓ Tremor was suppressed by test stimulation of the thalamic ventralis intermedius (VIM) nucleus at high frequency (130 Hz) during stereotaxy in nonanesthetized patients suffering from Parkinson's disease or essential tremor. Ventralis intermedius stimulation has since been used by the authors over the last 8 years as a treatment in 117 patients with movement disorders (80 cases of Parkinson's disease, 20 cases of essential tremor, and 17 cases of various dyskinesias and dystonias including four multiple sclerosis). Chronic electrodes were stereotactically implanted in the VIM and connected to a programmable stimulator. Results depend on the indication. In Parkinson's disease patients, tremor, but not bradykinesia and rigidity, was selectively suppressed for as long as 8 years. Administration ofl-Dopa was decreased by more than 30% in 40 Parkinson's disease patients. In essential tremor patients, results were satisfactory but deteriorated with time in 18.5% of cases, mainly for patients who presented an action component of their tremor. In other types of dyskinesias (except multiple sclerosis), results were much less favorable. Fifty-nine patients underwent bilateral implantation and 14 other patients received implantation contralateral to a previous thalamotomy. Thirty-seven patients (31.6%) experienced minor side effects, which were always well tolerated and immediately reversible. Three secondary scalp infections led to temporary removal of the implanted material. There was no permanent morbidity. This tremor suppression effect could be due to the inhibition or jamming of a retroactive loop. Chronic VIM stimulation, which is reversible, adaptable, and well tolerated even by patients undergoing bilateral surgery (74 of 117 patients) and by elderly patients, should replace thalamotomy in the regular surgical treatment of parkinsonian and essential tremors.
Protective effects of tirilazad mesylate and metabolite U-89678 against blood-brain barrier damage after subarachnoid hemorrhage and lipid peroxidative neuronal injury
Authors: Smith Sarah L. , Scherch Heidi M. , Hall Edward D.
Published: June 2009

✓ The 21-aminosteroid lipid-peroxidation inhibitor, tirilazad mesylate (U-74006F), recently was shown in a large multinational Phase III clinical trial to decrease mortality and improve neurological recovery in patients 3 months after onset of aneurysmal subarachnoid hemorrhage (SAH). A major tirilazad metabolite in animals and man, U-89678 is formed when the 4–5 double bond in the A-ring is reduced and has been postulated to contribute significantly to tirilazad's neuroprotective effects. In the first experiment of the present study, the authors compared the effects of tirilazad and U-89678 on acute blood-brain barrier (BBB) damage in rats subjected to SAH via injection of 300 µl of autologous nonheparinized blood under the dura of the left cortex. The rats were treated by intravenous administration of either 0.3 or 1.0 mg/kg of tirilazad or U-89678 10 minutes before and 2 hours after SAH, and BBB damage was quantified according to the extravasation of the protein-bound Evans' blue dye into the injured cortex 3 hours post-SAH. The results revealed that 0.3 and 1.0 mg/kg tirilazad significantly reduced SAH-induced BBB damage 35.2% (p < 0.05) and 60.6% (p < 0.0001), respectively, in comparison to treatment with vehicle. The 0.3- and 1.0-mg/kg doses of U-89678 also decreased injury by 39.1% (p < 0.05) and 21.3% (not significant), respectively. In the second experiment, the investigators assessed the relative abilities of tirilazad and U-89678 to protect cultured neurons from iron-induced lipid peroxidative injury. Fetal mouse spinal cord cells were pretreated with 3, 10, or 30 µM tirilazad or U-89678 for 1 hour and then exposed to 200 µM ferrous ammonium sulfate (FAS) for 40 minutes. Cell viability was measured in terms of the uptake of [3H]α-(methyl)-aminoisobutyric acid 45 minutes after the FAS treatment. Both compounds enhanced neuronal survival in a concentration-dependent fashion. Although the two were equally efficacious, U-89678 was slightly more potent than its parent. On the basis of these findings, the authors conclude that the tirilazad metabolite, U-89678, possesses vaso- and neuroprotective properties that are essentially equivalent to the parent 21-aminosteroid. Hence, U-89678 probably contributes to the protective effects of tirilazad in SAH and other insults to the central nervous system.
Reinnervation of avulsed and reimplanted ventral rootlets in the cervical spinal cord of the cat
Authors: Hoffmann Carel F. E. , Marani Enrico , van Dijk J. Gert , Kamp Wim V. D. , Thomeer Ralph T. W. M.
Published: June 2009

✓ Spinal nerve root avulsions frequently occur in brachial plexus injuries caused by traction. Such lesions are considered to afflict the central nervous system (CNS) and are, therefore, believed to be beyond surgical repair. The present experimental study was initiated to challenge this hypothesis. The ventral rootlets of C-7 were avulsed from the spinal cord in 28 cats via an anterior approach and subsequently reimplanted into the cord at the site of origin. In nonoperated control cats and cats undergoing reimplantation, electrophysiological experiments were performed and horseradish peroxidase was administered to the spinal nerve on the reimplanted side after survival times ranging from 6 to 293 days. Spinal cord sections in all cats were stained for neurofilament, acetylcholinesterase (AChE), Nissl, and glial fibrillary acidic protein. Horseradish peroxidase—labeled ventral horn motoneurons were found as early as 14 days after reimplantation and their number increased with time. On Days 209 and 293, the number of labeled neurons equaled the number of labeled ventral horn neurons in the two control cats that did not undergo surgery. Starting on Day 6 after reimplantation, the appearance of the ventral horn and the white matter in the neurofilament, AChE, and Nissl-stained sections changed as a result of the CNS response to the injury. A return to their normal appearance could be observed in these stainings from Day 209 onward. Glial fibrillary acidic protein—positive astrocytic tissue was consistently found in the ventral horn and in the white matter reimplantation area. From Day 69 onward, electrophysiological stimulation of the spinal nerve C-7 on the reimplanted side elicited an electromyogram response in the spinodeltoid muscle. The latency and threshold intensity of the C-7 responses were initially increased but equalized to match the nonoperated controls between 98 and 122 days after reimplantation. The results of this study show that functional regeneration of ventral horn neurons after root avulsion and subsequent reimplantation in the cat is possible.
Effects of spinal cord stimulation on the flexor reflex and involvement of supraspinal mechanisms: an experimental study in mononeuropathic rats
Authors: Ren Ben , Linderoth Bengt , Meyerson Björn A.
Published: June 2009

✓ The physiological mechanisms responsible for pain relief caused by spinal cord stimulation (SCS) are essentially unknown and recent experimental data are sparse. In the present study the authors explored the possible involvement of supraspinal mechanisms in the effects of SCS applied in rats with experimental mononeuropathy produced by sciatic nerve ligation according to the method of Bennett and Xie or that of Seltzer, et al. Confirming results of a previous study undertaken by the authors, the thresholds of the early component of the flexor reflex (latency 8–12 msec), which is mediated by A fibers, were significantly lower in the nerve-ligated than in the intact leg. In halothane-anesthetized animals the spinal cord was exposed and SCS was applied with parameters similar to those used in clinical SCS. Ten minutes of SCS produced a significant elevation of the lowered threshold of the early flexor component only in the nerve-ligated leg, and this augmentatory effect of SCS persisted for 30 to 40 minutes after cessation of the stimulation. The threshold elevation amounted to between 50% and 80% of the prestimulatory value and it was related to the intensity of SCS. The threshold of the late, C-fiber—mediated component of the flexor reflex was not influenced in either of the legs. After transection of the spinal cord at the T-6 level, there was a moderate threshold increase in both the early and late components in both legs, but the threshold of the early component in the nerve-ligated leg remained lower. Spinal cord stimulation produced an almost identical threshold increase in the early component in the nerve-ligated leg with the same time course as before the transection. There was no effect on the late component of the reflex in either leg. The results indicate that this effect of SCS in mononeuropathic rats does not necessarily involve supraspinal mechanisms; instead SCS is operative at a spinal, segmental level. In view of the similarities between the effects of therapeutic SCS on cutaneous hypersensibility in patients with peripheral neuropathic pain and the effects demonstrated in neuropathic rats, the clinical pain relief achieved with SCS may be produced, at least partially, by intraspinal mechanisms.
Induction of human autologous cytotoxic T lymphocytes against minced tissues of glioblastoma multiforme
Authors: Tsurushima Hideo , Liu Shu Qin , Tsuboi Koji , Yoshii Yoshihiko , Nose Tadao , Ohno Tadao
Published: June 2009

✓ The authors induced autologous cytotoxic T lymphocytes (CTLs) directly from peripheral blood lymphocytes by preparing a coculture of minced tissue fragments of glioblastoma multiforme (GBM) with interleukins-1, -2, -4, and -6 and interferon-g in RHAMa medium containing 5% autologous plasma for 2 weeks. At the end of this period, the frequencies of CD3+, CD4+, CD8+, and CD16+ lymphocytes were 95% to 99%, 40% to 62%, 37% to 38%, and 0.2%, respectively. The lymphocytes killed 82% to 100% of the GBM cells within 48 hours at an effector-to-target cell ratio of 1.67, whereas in a separate coculture, autologous lymphokine-activated killer (LAK) cells killed only 33% of GBM cells under the same conditions. The lymphocytes showed no cytotoxicity against LAK-sensitive Daudi cells, natural killer—sensitive K562 cells or autologous fibroblasts grown from the brain tumor, although they did show slight cytotoxicities against allogeneic GBM cell lines. These results lead the authors to suggest that the lymphocyte population contains specific CTLs for autologous brain tumor cells and that these CTLs could be effective in adoptive immunotherapy to combat brain tumor.
Intrathecal granuloma complicating chronic spinal infusion of morphine
Authors: Blount Jeffrey P. , Remley Kent B. , Yue Samuel K. , Erickson Donald L.
Published: June 2009

✓ Intrathecal morphine delivered by implanted pumps has been used in the treatment of pain caused by terminal cancer. Some authors supports its use in benign pain as well. The authors present three cases in which chronic infiltration of intraspinal narcotic medication was complicated by the formation of a granulomatous mass that became large enough to exert mass effect and induce neurological dysfunction.
Retrobulbar optic nerve cysticercosis
Authors: Bousquet Charles François , Dufour Thierry François Laurent , Derome Philippe Claude Eric
Published: June 2009

✓ The authors report a first case of intraoptic neurocysticercosis in a 12-year-old boy living on Reunion Island. Cysticercosis of the retrobulbar portion of the optic nerve is rare. Because of the patient's age and disturbances in both visual acuity and visual field, it was initially believed to be an optic nerve tumor. Computerized tomography scans and surgical aspects were confirmed by pathological findings. A conservative removal using en bloc orbitotomy showed good functional and aesthetic results.
Meningiomas of the tentorial notch: surgical anatomy and management
Authors: Samii Madjid , Carvalho Gustavo A. , Tatagiba Marcos , Matthies Cordula , Vorkapic Peter
Published: June 2009

✓ Twenty-five meningiomas located at the tentorial notch were surgically treated between 1978 and 1993 at the Neurosurgical Department of Nordstadt Hospital in Hannover, Germany. Nineteen meningiomas were classified as originating from the lateral tentorial incisura (Group I) and six were from the posteromedial tentorial incisura (Group II). Clinically, the most common symptom was trigeminal neuralgia, followed by headache. Neuroradiologically, 64% of the meningiomas were larger than 30 × 30 mm. Further evaluation revealed signs of brainstem compression in 88% of the patients. Radical surgical removal (Simpson I and II) was achieved in 88% of the cases. There was no mortality. Follow up revealed that 80% of patients were able to return to their premorbid activity. Surgical approaches to the tentorial notch included the suboccipital retrosigmoidal or the combined subtemporal—presigmoidal approach for Group I tentorial notch meningiomas; and the supracerebellar—infratentorial or the suboccipital—transtentorial approaches for Group II meningiomas. Because the best surgical approach to the tentorial incisura is still a matter of debate, the anatomy of the tentorial incisura, the clinical presentation of the patients, diagnostic indications, surgical findings, and follow up are discussed, with reference to the literature.
Endovascular treatment of basilar tip aneurysms using electrolytically detachable coils
Authors: McDougall Cameron G. , Halbach Van V. , Dowd Christopher F. , Higashida Randall T. , Larsen Donald W. , Hieshima Grant B.
Published: June 2009

✓ Preliminary experience using electrolytically detachable coils to treat basilar tip aneurysms in 33 patients is described. The most frequent presentation was subarachnoid hemorrhage (SAH) in 23 patients. All patients were referred after neurosurgical assessment and exclusion as candidates for surgical clipping of their aneurysms. At the time of initial treatment complete aneurysm occlusion was achieved in seven (21.2%) of 33 patients. In 17 of the patients (51.5%), greater than 90% but less than 100% aneurysm occlusion was achieved. Angiographic follow up (mean 11.7 months) was available in 19 patients. At follow-up angiography four (21%) of 19 aneurysms were 100% occluded and 12 (63.2%) of 19 were more than 90% but less than 100% occluded.

The mean clinical follow-up time in treated patients surviving beyond the initial treatment period is 15 months. One patient suffered major permanent morbidity from thrombosis of the basilar tip region a few hours after coil placement. One patient treated following SAH experienced further hemorrhage 6 months later. No other patient suffered direct or indirect permanent morbidity as a consequence of this method of treatment.

The authors believe that this technique is a reasonable alternative for patients who are not candidates for conventional surgical treatment or in whom such treatment has failed. This study's follow-up period is brief and greater experience with long-term follow-up study is mandatory.
Efficacy of prophylactic nimodipine for delayed ischemic deficit after subarachnoid hemorrhage: a metaanalysis
Authors: Barker Fred G. , Ogilvy Christopher S.
Published: June 2009

✓ The authors report findings from a metaanalysis of all published randomized trials of prophylactic nimodipine used in patients who have experienced subarachnoid hemorrhage (SAH). Seven trials were included with a total of 1202 patients suitable for evaluation. Eight outcome measures were examined, including good versus other outcome, good or fair outcome versus other outcome, overall mortality, deficit and/or death attributed to vasospasm, infarction rate as judged by computerized tomography (CT), and deficit and/or death from rebleeding.

Nimodipine improved outcome according to all measures examined. The odds of good and of good plus fair outcomes were improved by ratios of 1.86:1 and 1.67:1, respectively, for nimodipine versus control (p < 0.005 for both measures). The odds of deficit and/or mortality attributed to vasospasm and CT-assessed infarction rate were reduced by ratios of 0.46:1 to 0.58:1 in the nimodipine group (p < 0.008 for all measures). Overall mortality was slightly reduced in the nimodipine group, but the trend was not statistically significant. The rebleeding rate was not increased by nimodipine. A metaregression yielded findings indicating that the treatment effect of nimodipine in individual trials was positively correlated with the severity of SAH in enrolled patients.

Although the majority of individual trials examined did not have statistically significant results at the p < 0.01 level according to most outcome measures, the metaanalyses confirmed the significant efficacy of prophylactic nimodipine in improving outcome after SAH under the conditions used in these trials.
Central nervous system medulloepithelioma: a series of eight cases including two arising in the pons
Authors: Molloy Patricia T. , Yachnis Anthony T. , Rorke Lucy B. , Dattilo James J. , Needle Michael N. , Millar William S. , Goldwein Joel W. , Sutton Leslie N. , Phillips Peter C.
Published: June 2009

✓ Medulloepithelioma is an uncommon childhood tumor of the central nervous system (CNS) whose histopathological appearance has been confused with medulloblastoma and other childhood primitive neuroectodermal tumors (PNETs), but which has a vastly different clinical course. The authors have reviewed the clinical features and treatment responses of eight children with these rare tumors, the largest series to date.

In this series, the medulloepitheliomas were equally distributed between supratentorial and infratentorial primary sites. Four patients underwent gross- or near-total resections, one patient's tumor was partially resected, and one patient had biopsy only. Biopsy and ablative surgery were not attempted in two children with pontine tumors. Treatment included both radiation and chemotherapy (four patients), radiation alone (one patient), chemotherapy alone (one patient), and no postoperative treatment (two patients). Six patients died with a mean survival of 10 months and two are disease free with neurological impairment. Both long-term survivors underwent gross-total resections of their tumors. Postmortem examination revealed diffuse CNS tumor dissemination in four patients.

Medulloepithelioma, often confused with less aggressive PNETs, can mimic intrinsic brainstem glioma, responds poorly to treatment, and is prone to CNS dissemination at the time of tumor progression.
Proton magnetic resonance spectroscopy in patients with glial tumors: a multicenter study
Authors: Negendank William G. , Sauter Rolf , Brown Truman R. , Evelhoch Jeffrey L. , Falini Andrea , Gotsis Efstathios D. , Heerschap Arend , Kamada Kyousuke , Lee Benjamin C. P. , Mengeot Michel M. , Moser Ewald , Padavic-Shaller Kristin A. , Sanders John A. , Spraggins Thomas A. , Stillman Arthur E. , Terwey Burckhard , Vogl Thomas J. , Wicklow Karsten , Zimmerman Robert A.
Published: June 2009

✓ The authors represent a cooperative group of 15 institutions that examined the feasibility of using metabolic features observed in vivo with 1H-magnetic resonance (MR) spectroscopy to characterize brain tumors of the glial type. The institutions provided blinded, centralized MR spectroscopy data processing along with independent central review of MR spectroscopy voxel placement, composition and contamination by brain, histopathological typing using current World Health Organization criteria, and clinical data. Proton 1H-MR spectroscopy was performed using a spin-echo technique to obtain spectra from 8-cc voxels in the tumor and when feasible in the contralateral brain. Eighty-six cases were assessable, 41 of which had contralateral brain spectra. Glial tumors had significantly elevated intensities of choline signals, decreased intensities of creatine signals, and decreased intensities of N-acetylaspartate compared to brain. Choline signal intensities were highest in astrocytomas and anaplastic astrocytomas, and creatine signal intensities were lowest in glioblastomas. However, whether expressed relative to brain or as intratumoral ratios, these metabolic characteristics exhibited large variations within each subtype of glial tumor. The resulting overlaps precluded diagnostic accuracy in the distinction of low- and high-grade tumors. Although the extent of contamination of the 1HMR spectroscopy voxel by brain had a marked effect on metabolite concentrations and ratios, selection of cases with minimal contamination did not reduce these overlaps. Thus, each type and grade of tumor is a metabolically heterogeneous group. Lactate occurred infrequently and in all grades. Mobile lipids, on the other hand, occurred in 41% of high-grade tumors with higher mean amounts found in glioblastomas. This result, coupled with the recent demonstration that intratumoral mobile lipids correlate with microscopic tumor cell necrosis, leads to the hypothesis that mobile lipids observed in vivo in 1H-MR spectroscopy may correlate independently with prognosis of individual patients.
Color transcranial “power” Doppler ultrasound of intracranial aneurysms
Authors: Wardlaw Joanna M. , Cannon James C.
Published: June 2009

✓ “Color Doppler energy” (or “power Doppler”), a new color Doppler ultrasound technique that is independent of flow direction and very sensitive to movement, was assessed for its use in the identification of intracranial aneurysms in patients with recent subarachnoid hemorrhage immediately prior to using cerebral angiography. Features that identified aneurysms using this technique included the appearance of abnormal color where no normal artery was expected, abnormal bulging of an artery, and greater “expansibility” of the aneurysm in comparison to an adjacent normal vessel. In this exploratory study, 30 of 33 aneurysms were correctly identified in 35 patients with a good bone window. Color Doppler energy is considerably more sensitive to intracranial blood flow than conventional color Doppler imaging. Color Doppler energy is a useful research tool; if these preliminary results are verified in larger series, in addition to examination for vasospasm, the technique could be used for identification and follow up of aneurysms.
Transforaminal arthroscopic decompression of lateral recess stenosis
Authors: Kambin Parviz , Casey Kenneth , O'Brien Evan , Zhou Linqui
Published: June 2009

✓ The purpose of this study was to evaluate the feasibility and efficacy of arthroscopic decompression of lateral recess stenosis, determine potential associated complications, and present an alternative method to access the lateral recess of the lumbar spine. Forty patients were selected in whom the authors found clinical and computerized tomography evidence of lateral recess stenosis and sequestered foraminal herniations. All 40 were treated with a posterolateral arthroscopic technique, and 38 were available for this follow-up evaluation. A satisfactory result was obtained in 31 patients (82%). No neurovascular complications were encountered; however, other complications included an infection of the disc space in one patient and a causalgic-type pain in the involved extremity in four patients. The associated postoperative morbidity in this group of patients was minimal and resulted in rapid rehabilitation and return of patients to preoperative functioning level.
Prevention of subarachnoid hemorrhage—induced cerebral vasospasm by oral administration of endothelin receptor antagonists
Authors: Zuccarello Mario , Soattin Giovanni B. , Lewis Adam I. , Breu Volker , Hallak Hussein , Rapoport Robert M.
Published: June 2009

✓ The purpose of this study was to investigate the effectiveness of oral treatment with the endothelin (ET)A/Breceptor antagonist Ro 47-0203, 4-tert-butyl-N-[6-(hydroxy-ethoxy)-5-(2-methoxy-phenoxy)-2′-bipyrimidin-4-yl]-benzenesulfonamide (bosentan), and the ETAreceptor antagonist 2-benzo[1,3]dioxol-5-yl-3-benzyl-4-(4-methoxy-phenyl)-4-oxobut-2-enoic acid monosodium salt (PD155080), in the prevention of subarachnoid hemorrhage (SAH)—induced delayed cerebral vasospasm. Double hemorrhage in the rabbit constricted the basilar artery to 34% of control as determined by angiography. Oral bosentan and PD155080 administration after the initial SAH decreased the magnitude of constriction to 9% and 16% of control, respectively. Plasma and cerebrospinal fluid bosentan levels and plasma PD155080 levels were consistent with concentrations reported to inhibit ET-1 constriction of blood vesselsin vitro. These results support the use of oral administration of ETA/Band ETAreceptor antagonists as potential specific treatment for vasospasm resulting from SAH in humans.
Ovine pericardium as a new material for duraplasty
Authors: Pařízek Jan , Husěk Zdeněk , Měřička Pavel , Téra Josef , Němeček Stanislav , Spaček Josef , Němečková Jana , Šuba Petr
Published: June 2009

✓ The authors report on their 2 1/2-year clinical experience using a dural substitute, ovine pericardium, stabilized with 0.3% glutaraldehyde, flat freeze-dried, and sterilized with γ-irradiation.

Packaging of the ovine pericardium in double-plastic transparent bags allows simple storage in operating rooms and the opportunity for the surgeon to choose an ideal graft according to its shape, size, and plasticity.

The ovine pericardia were examined histologically and by transmission and scanning electron microscopy in their native, freeze-dried, and irradiated forms. The final product is composed solely of pericardium fibrosum interwoven with artificially formed extracellular microcavities that serve as natural pores for the ingrowth of host tissue. The surfaces of the grafts appear smooth on the inner and rough on the outer sides.

Sixteen grafts were examined macroscopically at autopsy and four of these were also examined histologically to illustrate their successful healing with no adhesion to the underlying brain.

As a new dural substitute, ovine pericardium proved to be superior to bovine and allogeneic pericardia because of its workability, flexibility, and reduced thickness. In a study of 120 grafts, all but one healed without complications.
Sinus skeletonization: a treatment for dural arteriovenous malformation of the tentorial apex
Authors: Lucas César P. , Oliveira Evandro de , Tedeschi Helder , Siqueira Mario , Lourenzi Mario , Piske Ronie L. , Conti Mario , Peace David
Published: June 2009

✓ Two cases of dural arteriovenous malformation of the tentorial apex are presented. Both were treated surgically by means of a sinus skeletonization technique. The operative technique included a combined bioccipital and median suboccipital craniotomy in which the posterior third of the superior sagittal and the straight and bilateral transverse sinuses were skeletonized by incising the falx and the tentorium along the sinuses. Endovascular embolization was used prior to the surgical approach in one case. Clinical and angiographic cure was achieved in both patients, with a follow up of 4 years in the first case and 1 year in the second one. The surgical technique is described in detail.
Spinal arachnoid cyst developing after surgical treatment of a ruptured vertebral artery aneurysm: a possible complication of topical use of fibrin glue
Authors: Taguchi Yoshio , Suzuki Rie , Okada Masaaki , Sekino Hiroaki
Published: June 2009

✓ A case is reported of a 59-year-old man with a spinal arachnoid cyst accompanied by spinal arachnoiditis. The patient developed symptoms after treatment for a ruptured vertebral artery aneurysm, in which fibrin glue was used for reconstruction of the suboccipital bone defect. It is believed that the fibrin glue may have played a role in forming the arachnoid cyst. The authors urge the readers to keep in mind the possibility of subclinical spinal arachnoiditis in the patients with aneurysmal subarachnoid hemorrhage and suggest that care should be taken to avoid any possible adverse effect of fibrin glue.