bluuebunny/crossref_metadata_2025 huggingface dataset:
Capillary hemangioma of the central nervous system
Authors: Abe Masamitsu , Tabuchi Kazuo , Tanaka Shin , Hodozuka Akira , Kunishio Katsuzo , Kubo Naohiko , Nishimura Yukimasa
Published: May 2009

Object. Capillary hemangiomas are benign tumors or tumorlike lesions that originate from blood vessels and have rarely been reported to develop in the brain or spinal cord. The authors summarize the clinical and histological features of capillary hemangiomas of the central nervous system (CNS).

Methods. The clinical features, imaging characteristics, and outcomes in 10 patients with CNS capillary hemangiomas were reviewed. Histological studies included immunostaining with CD31, α-smooth muscle actin, vascular endothelial growth factor, and Ki-67 antigen. Three patients with lesions in the brain presented with symptoms of increased intracranial pressure or seizures. Seven patients with lesions in the spinal cord presented with progressive sensorimotor disturbances of the lower limbs. Computerized tomography and magnetic resonance imaging demonstrated well-defined, enhancing lesions associated with marked perifocal edema. Angiography demonstrated hypervascular lesions, which have not recurred after resection. In two cases, multiple satellite lesions resolved after the systemic administration of steroid drugs or interferon-α. Histologically, all lesions were consistent with findings of capillary hemangioma of the skin or soft tissues. The CNS lesions differed significantly from other vascular neoplasms, such as hemangioendotheliomas, hemangiopericytomas, and hemangioblastomas.

Conclusions. Capillary hemangiomas of the CNS are benign lesions that can be surgically removed and cured without adjuvant therapy.
Prospective risk of hemorrhage in patients with vertebrobasilar nonsaccular intracranial aneurysm
Authors: Flemming Kelly D. , Wiebers David O. , Brown Robert D. , Link Michael J. , Nakatomi Hirofumi , Huston John , McClelland Robyn , Christianson Teresa J. H.
Published: May 2009

Object. Nonsaccular intracranial aneurysms (NIAs) are characterized by dilation, elongation, and tortuosity of intracranial arteries. Dilemmas in management exist due to the limited regarding the natural history of this disease entity. The objective of this study was to determine the prospective risk of subarachnoid hemorrhage (SAH) in patients with vertebrobasilar NIAs.

Methods. All patients with vertebrobasilar fusiform or dolichoectatic aneurysms that had been radiographically demonstrated between 1989 and 2001 were identified. These patients' medical records were retrospectively reviewed. A prospective follow-up survey was sent and death certificates were requested. Based on results of neuroimaging studies, the maximal diameter of the involved artery, presence of SAH, and measurements of arterial tortuosity were recorded. Nonsaccular intracranial aneurysms were classified according to their radiographic appearance: fusiform, dolichoectatic, and transitional. Dissecting aneurysms were excluded. The aneurysm rupture rate was calculated based on person-years of follow up. Predictive factors for rupture were evaluated using univariate analysis (p < 0.05). One hundred fifty-nine patients, 74% of whom were men, were identified. The mean age at diagnosis was 64 years (range 20–87 years). Five patients (3%) initially presented with hemorrhage; four of these patients died during follow up. The mean duration of follow up was 4.4 years (692 person-years). Nine patients (6%) experienced hemorrhage after presentation; six hemorrhages were definitely related to the NIA. The prospective annual rupture rate was 0.9% (six patients/692 person-years) overall and 2.3% in those with transitional or fusiform aneurysm subtypes. Evidence of aneurysm enlargement or transitional type of NIA was a significant predictor of lesion rupture. Six patients died within 1 week of experiencing lesion rupture.

Conclusions. Risk of hemorrhage in patients harboring vertebrobasilar NIAs is more common in those with evidence of aneurysm enlargement or a transitional type of aneurysm and carries a significant risk of death.
Prevention of vasospasm by anti-CD11/CD18 monoclonal antibody therapy following subarachnoid hemorrhage in rabbits
Authors: Pradilla Gustavo , Wang Paul P. , Legnani Federico G. , Ogata Lynn , Dietsch Gregory N. , Tamargo Rafael J.
Published: May 2009

Object.Adhesion of leukocytes and their migration into the periadventitial space may be critical in the pathophysiology of vasospasm following subarachnoid hemorrhage (SAH). The cell adhesion molecules involved in this process are lymphocyte function—associated antigen—1 (CD11a/CD18) and macrophage antigen—1 (CD11b/CD18), which are present on neutrophils/macrophages, and intercellular adhesion molecule—1 (CD54), which is present in endothelial cells. A humanized monoclonal antibody (mAb), Hu23F2G, targets CD11/CD18 and prevents leukocyte adhesion to endothelial cells. In this study, systemic administration of Hu23F2G prevented vasospasm in the rabbit model of SAH.

Methods.Twenty-six New Zealand White rabbits were injected with autologous blood into the cisterna magna to induce SAH, after which they were randomized to receive injections of either Hu23F2G (10 animals) or a placebo at 30 minutes and 24 and 48 hours after SAH (six animals). Control animals underwent sham operations (four animals) or SAH alone (six animals). The animals were killed 72 hours after SAH, their bodies perfused and fixed, and their basilar arteries processed for morphometric analysis. Peripheral white blood cells (WBCs) were counted at 72 hours. The percentages of lumen patency were compared using the Student t-test. The presence of neutrophils and macrophages was confirmed by immunohistochemical analysis in which a rat anti—rabbit anti-CD18 mAb and cresyl violet were used.

Treatment with Hu23F2G resulted in the significant prevention of vasospasm. Animals treated with Hu23F2G had 90 ± 7% lumen patency compared with 65 ± 7% in the placebo group (p = 0.025). The percentage of lumen patency in the SAH-only group was 59 ± 10%. The mean WBC count was 16,300 ± 2710/µl in the treatment group, compared with 7000 ± 386/µl in the control group (p = 0.02). Administration of Hu23F2G produced increased numbers of WBCs in 70% of the animals treated.

Conclusions.This study supports the concept that leukocyte—endothelial cell interactions play an important role in the pathophysiology of chronic vasospasm after SAH. Systemic therapy with an anti-CD11/CD18 mAb prevents vasospasm after SAH by inhibiting adhesion of neutrophils and macrophages and their migration into the periadventitial space.
Bifurcation geometry and the presence of cerebral artery aneurysms
Authors: Ingebrigtsen Tor , Morgan Michael K. , Faulder Ken , Ingebrigtsen Linda , Sparr Trygve , Schirmer Henrik
Published: May 2009

Object. The angles of arterial bifurcations are governed by principles of work minimization (optimality principle). This determines the relationship between the angle of a bifurcation and the radii of the vessels. Nevertheless, the model is predicated on an absence of significant communication between these branches. The circle of Willis changes this relationship because the vessels proximal to the ring of vessels have additional factors that determine work minimization compared with more distal branches. This must have an impact on understanding of the relationship between shear stress and aneurysm formation. The authors hypothesized that normal bifurcations of cerebral arteries beyond the circle of Willis would follow optimality principles of minimum work and that the presence of aneurysms would be associated with deviations from optimum bifurcation geometry. Nevertheless, the vessels participating in (or immediately proximal to) the circle of Willis may not follow the geometric model as it is generally applied and this must also be investigated.

Methods. One hundred seven bifurcations of the middle cerebral artery (MCA), distal internal carotid artery (ICA), and basilar artery (BA) were studied in 55 patients. The authors analyzed three-dimensional reconstructions of digital subtraction angiography images with respect to vessel radii and bifurcation angles. The junction exponent (that is, a calculated measure of the division of flow at the bifurcation) and the difference between the predicted optimal and observed branch angles were used as measures of deviation from the geometry thought best to minimize work.

The mean junction exponent for MCA bifurcations was 2.9 ± 1.2 (mean ± standard deviation [SD]), which is close to the theoretical optimum of 3, but it was significantly smaller (p < 0.001; 1.7 ± 0.8, mean ± SD) for distal ICA bifurcations. In a multilevel multivariate logistic regression analysis, only the observed branch angles were significant independent predictors for the presence of an aneurysm. The odds ratio (OR) (95% confidence interval) for the presence of an aneurysm was 3.46 (1.02–11.74) between the lowest and highest tertile of the observed angle between the parent vessel and the largest branch. The corresponding OR for the smallest branch was 48.06 (9.7–238.2).

Conclusions. The bifurcation beyond the circle of Willis (that is, the MCA) closely approximated optimality principles, whereas the bifurcations within the circle of Willis (that is, the distal ICA and BA) did not. This indicates that the confluence of hemodynamic forces plays an important role in the distribution of work at bifurcations within the circle of Willis. In addition, the observed branch angles were predictors for the presence of aneurysms.
Enhancement of C2-ceramide antitumor activity by small interfering RNA on X chromosome—linked inhibitor of apoptosis protein in resistant human glioma cells
Authors: Hatano Manabu , Mizuno Masaaki , Yoshida Jun
Published: May 2009

Object. Many human glioma cells are resistant to ceramide. In this study the authors investigated the mechanisms of that resistance and considered ways to overcome it.

Methods. The authors first administered C2-ceramide (N-acetylsphingosine) to human glioma cells from rare cell lines susceptible to C2-ceramide (SKMG1 and U87MG) and other cell lines resistant to it (U251SP, T98G, SKAO2, and U251MG). Following this, the authors analyzed the statuses of transduction signals such as cell viability, morphological changes, caspases, mitochondrial membrane potential, apoptosis-inducing factor, oligonucleosomal DNA fragmentation, and the inhibitor of apoptosis protein (IAP) family.

Conclusions. Ceramide resistance was found to arise from the inhibition of caspase-7 induced by IAPs, especially X chromosome—linked IAP (XIAP). Small interfering RNA (siRNA) on XIAP quenched that resistance in ceramide-resistant human glioma cells (U251SP, T98G, SKAO2, U251MG), indicating that a siRNA for XIAP may be a useful tool for overcoming the resistance to ceramide in human glioma cells.
Effects of aminoguanidine and l-arginine methyl ester resuscitation following induction of fluid percussion injury and severe controlled hemorrhagic shock in the rat brain
Authors: Atan Md Shirhan , Moochhala Shabbir M. , Ng Kian Chye , Low Kerwin , Teo Ai Ling , Lu Jia
Published: May 2009

Object.In this study the authors compared the effects of both a selective inducible nitric oxide synthase (iNOS) inhibitor and a nonselective inhibitor on posttraumatic recovery and neuron survival by using a combined model of lateral fluid percussion injury (FPI) and hemorrhagic shock (HS).

Methods.Male Sprague—Dawley rats weighing 300 to 350 g underwent FPI to the brain (3.5 atm) and hemorrhage to a mean arterial blood pressure (MABP) of 40 mm Hg for 1 hour. Rats were then resuscitated during 1 hour with bolus infusions of aminoguanidine (AG) or nitro-l-arginine methyl ester (l-NAME). Neuronal apoptosis was determined by performing Nissl staining and in situ terminal deoxynucleotidyl transferase—mediated deoxyuridine triphosphate nick-end labeling technique. Rats infused with AG showed a significant increase in mean survival time and cerebral tissue perfusion, although the MABP and nitrate/nitrite levels did not significantly change compared with those inl-NAME—treated rats even though both animal groups had been subjected to combined FPI and HS, FPI alone, or HS alone. Furthermore, infusion of AG also significantly decreased the number of apoptotic neurons when compared with the number in rats treated withl-NAME.

Conclusions.The authors asserted that treatment with AG, which causes the inhibition of iNOS, might contribute to improved physiological parameters and neuronal cell survival following FPI and HS.
Pulsed holmium:yttrium-aluminum-garnet laser—induced liquid jet as a novel dissection device in neuroendoscopic surgery
Authors: Nakagawa Atsuhiro , Hirano Takayuki , Jokura Hidefumi , Uenohara Hiroshi , Ohki Tomohiro , Hashimoto Tokitada , Menezes Viren , Sato Yasuhiko , Kusaka Yasuko , Ohyama Hideki , Saito Tsutomu , Takayama Kazuyoshi , Shirane Reizo , Tominaga Teiji
Published: May 2009

Object.A pressure-driven continuous jet of water has been reported to be a feasible tool for neuroendoscopic dissection owing to its superiority at selective tissue dissection in the absence of thermal effects. With respect to a safe, accurate dissection, however, continuous water flow may not be suitable for intraventricular use. The authors performed experiments aimed at solving problems associated with continuous flow by using a pulsed holmium:yttrium-aluminum-garnet (Ho:YAG) laser-induced liquid jet (LILJ). They present this candidate neuroendoscopic LILJ dissection system, having examined its mechanical characteristics and evaluated its controllability both in a tissue phantom and in a rabbit cadaveric ventricle wall.

Methods.The LILJ generator was incorporated into the tip of a No. 4 French catheter so that the LILJ could be delivered via a neuroendoscope. Briefly, the LILJ was generated by irradiating an internally supplied column of physiological saline with a pulsed Ho:YAG laser (pulse duration time 350 µsec; laser energy 250–700 mJ/pulse) within a No. 4 French catheter (internal diameter 1 mm) and ejecting it from a metal nozzle (internal diameter 100 µm). The Ho:YAG laser energy pulses were conveyed by an optical fiber (core diameter 400 µm) at 3 Hz, whereas physiological saline (4°C) was supplied at a rate of 40 ml/hour. The mechanical characteristics of the pulsed LILJ were investigated using high-speed photography and pressure measurements; thermal effects and controllability were analyzed using an artificial tissue model (10% gelatin of 1 mm thickness). Finally, the ventricle wall of a rabbit cadaver was dissected using the LILJ.

Jet pressure increased in accordance with laser energy from 0.1 to 2 bar; this translated into a penetration depth of 0.08 to 0.9 mm per shot in the ventricle wall of the rabbit cadaver. The gelatin phantom could be cut into the desired shape without significant thermal effects and in the intended manner, with a good surgical view.

Conclusions.The present results show that the pulsed LILJ has the potential to become a safe and reliable dissecting method for endoscopic procedures.
Emergency stent placement for symptomatic acute carotid artery occlusion after endarterectomy
Authors: Kim Stanley H. , Qureshi Adnan I. , Levy Elad I. , Hanel Ricardo A. , Siddiqui Amir M. , Hopkins L. Nelson
Published: May 2009

✓ The authors report a case of emergency carotid artery (CA) stent placement for a symptomatic acute CA occlusion following carotid endarterectomy (CEA). This 43-year-old man underwent a right-sided CEA for an asymptomatic 80% CA stenosis detected using duplex ultrasound testing. The patient experienced hypotension and possibly a myocardial infarction intraoperatively and a left hemiplegia immediately postoperatively. He was referred to the authors' institution for consideration of emergency coronary intervention and evaluation of stroke. A computerized tomography scan of the head demonstrated subtle early ischemic changes in the right posterior parietal region. Cerebral angiography revealed occlusion of the right common CA (CCA) at the CA bifurcation. Two coronary stents (Magic Wall; Boston Scientific Scimed, Maple Grove, MN) were placed in tandem in the right CCA and internal CA (ICA), overlapping at the proximal cervical ICA. Complete recanalization of the CA was achieved, and the patient made a clinically significant recovery. Diagnostic angiography can provide important information about CA and intracranial circulation that will aid in the evaluation of postoperative stroke after CEA. Stent placement should be considered as an alternative method of treatment for acute CA occlusion or dissection following CEA.
Large anterior skull base lesions presenting with obstructive sleep apnea
Authors: Murali Raj , Douyon Philippe , Omeis Ibrahim
Published: May 2009

✓ Patients with sleep apnea often are treated by sleep disorder specialists and are studied in a sleep laboratory. The authors present two such patients who ultimately were found to harbor large benign anterior skull base lesions that caused their obstructive sleep apnea (OSA). The first patient had a massive pituitary tumor and had undergone a tracheostomy before the lesion was diagnosed. The second patient had a large frontoethmoidal encephalocele that was diagnosed at the same time as a recommendation for continuous positive airway pressure therapy was being considered. Such therapy in the presence of an encephalocele can be dangerous and even fatal. Although there are case reports of tumors causing OSA, nearly all of these lesions have been large pharyngeal lipomas (some of which were palpable in the neck during physical examination) or growth hormone—secreting pituitary adenomas. The patients reported here were completely unaware of the presence of these large lesions until imaging studies and/or nasal endoscopy were performed. These cases illustrate the need to perform nasopharyngeal endoscopy and also to obtain magnetic resonance images of the head before prescribing therapy for OSA. Neurosurgeons must be aware that large skull base lesions sometimes present only with OSA.
Deep brain stimulation for dystonia confirming a somatotopic organization in the globus pallidus internus
Authors: Vayssiere Nathalie , van der Gaag Niels , Cif Laura , Hemm Simone , Verdier Regis , Frerebeau Philippe , Coubes Philippe
Published: May 2009

Object. In patients with dystonia, symptoms vary greatly in their extent and severity. The efficacy of pallidal stimulation is now established, but an interindividual variability in the responses to this treatment exists. A retrospective analysis of postoperative magnetic resonance (MR) images demonstrated millimetric variations in the positions of electrode contacts inside the posterolateroventral portion of the globus pallidus internus (GPi). It therefore seemed very likely that there is a somatotopic organization within the GPi. The goal of this study was to examine the positions of specific electrode contacts according to patients' clinical evolution, so that a somatotopic organization within the GPi could be defined.

Methods. This study included 19 patients (17 of whom were right handed) with generalized dystonia who were treated by bilateral stimulation of the GPi. Patients were examined pre- and postoperatively by using the Burke-Fahn-Marsden Dystonia Rating Scale. Dividing the patient's body into three parts—cervicoaxial area, superior limb, and inferior limb—we determined the following: 1) where the dystonic symptoms started; 2) where symptoms predominated at the time of surgery; and 3) where the highest postoperative improvement was observed.

Variations in clinical response were correlated to the positions of the electrode contacts. All activated electrode contacts were in the posterolateroventral portion of the GPi (Laitinen target). A correlation between the contact location measured longitudinally and the part of the body in which the highest improvement was observed (three different areas; p = 0.004) showed that a location more anterior for the inferior limb and one more posterior for the superior limb were delineated for the right side, but not for the left side.

Conclusions. Inside the posterolateroventral subvolume of the GPi on the right side, three statistically different locations of electrode contacts were determined to be primary deep brain stimulation treatment sites for particular body parts in cases of dystonia.
Influence of apoptosis on neurological outcome following traumatic cerebral contusion
Authors: Nathoo Narendra , Narotam Pradeep K. , Agrawal Devendra K. , Connolly Catherine A. , van Dellen James R. , Barnett Gene H. , Chetty Runjan
Published: May 2009

Object. Apoptosis has increasingly been implicated in the pathobiology of traumatic brain injury (TBI). The present study was undertaken to confirm the presence of apoptosis in the periischemic zone (PIZ) of traumatic cerebral contusions and to determine the role of apoptosis, if any, in neurological outcome.

Methods. Brain tissue harvested at Wentworth Hospital from the PIZ in 29 patients with traumatic supratentorial contusions was compared with brain tissue resected in patients with epilepsy. Immunohistochemical analyses were performed on the tissues to see if they contained the apoptosis-related proteins p53, bcl-2, bax, and caspase-3. The findings were then correlated to demographic, clinical, surgical, neuroimaging, and outcome data.

In the PIZ significant increases of bax (18-fold; p < 0.005) and caspase-3 (20-fold; p < 0.005) were recorded, whereas bcl-2 was upregulated in only 14 patients (48.3%; 2.9-fold increase) compared with control tissue. Patients in the bcl-2—positive group exhibited improved outcomes at the 18-month follow-up examination despite an older mean age and lower mean admission Glasgow Coma Scale score (p < 0.03). Caspase-3 immunostaining was increased in those patients who died (Glasgow Outcome Scale [GOS] Score 1, 12 patients) when compared with those who experienced a good outcome (GOS Score 4 or 5, 17 patients) (p < 0.005). Regression analysis identified bcl-2—negative status (p < 0.04, odds ratio [OR] 5.5; 95% confidence interval [CI] 1.1–28.4) and caspase-3—positive status (p < 0.01, OR 1.4, 95% CI 1.1—1.8) as independent predictors of poor outcome. No immunostaining for p53 was recorded in the TBI specimens.

Conclusions. The present findings confirm apoptosis in the PIZ of traumatic cerebral contusions and indicate that this form of cell death can influence neurological outcome following a TBI.
Localization of hand sensory function to the pli de passage moyen of Broca
Authors: Boling Warren W. , Olivier André
Published: May 2009

Object. The goal of this study was to identify a reliable landmark for hand sensory function in the central area.

Methods. Hand sensory activation on positron emission tomography (PET) scans was analyzed in 27 patients. Each PET study was coregistered with the patient's magnetic resonance image and analyzed in two-dimensional and three-dimensional cortical surface reconstructions to define anatomicofunctional relationships.

Conclusions. The substratum of hand sensory function is a prominent fold of cortex elevating the floor of the central sulcus and connecting the pre- and postcentral gyri. Broca named this cortical fold the pli de passage moyen, and hand motor function has been localized to the precentral component of this structure. In this study the authors demonstrate that hand sensory function is highly correlated with the postcentral component of the pli de passage moyen, and that this structure is a reliable cortical landmark for identifying the aforementioned function.
Coerced training of the nondominant hand resulting in cortical reorganization: a high-field functional magnetic resonance imaging study
Authors: Nakada Tsutomu , Fujii Yukihiko , Kwee Ingrid L.
Published: May 2009

Object. The authors investigated brain strategies associated with hand use in an attempt to clarify genetic and nongenetic factors influencing handedness by using high-field functional magnetic resonance imaging.

Methods. Three groups of patients were studied. The first two groups comprised individuals in whom handedness developed spontaneously (right-handed and left-handed groups). The third group comprised individuals who were coercively trained to use the right hand and developed mixed handedness, referred to here as trained ambidexterity. All trained ambidextrous volunteers were certain that they were innately left-handed, but due to social pressure had modified their preferred hand use for certain tasks common to the right hand.

Although right-handed and left-handed volunteers displayed virtually identical cortical activation, involving homologous cortex primarily located contralateral to the hand motion, trained ambidextrous volunteers exhibited a clearly unique activation pattern. During right-handed motion, motor areas in both hemispheres were activated in these volunteers. During left-handed motion, the right supplemental motor area and the right intermediate zone of the anterior cerebellar lobe were activated significantly more frequently than observed in naturally right-handed or left-handed volunteers.

Conclusions. The results provide strong evidence that cortical organization of spontaneously developed right- and left-handedness involves homologous cortex primarily located contralateral to the hand motion, and this organization is likely to be prenatally determined. By contrast, coerced training of the nondominant hand during the early stages of an individual's development results in mixed handedness (trained ambidexterity), indicating cortical reorganization.
Whipple disease confined to the central nervous system presenting as a solitary frontal tumor
Authors: Löhr Mario , Stenzel Werner , Plum Georg , Gross Wulf-Peter , Deckert Martina , Klug Norfrid
Published: May 2009

✓ Whipple disease is a rare infection caused by the bacterium Tropheryma whippelii. Patients usually present with gastrointestinal symptoms or migratory arthralgias. Although symptomatic central nervous system (CNS) involvement frequently occurs, Whipple disease confined to the CNS is rare. The authors present the case of a 40-year-old man who was surgically treated for a symptomatic left frontal tumor that had the neuroimaging features of a low-grade glioma (LGG). A histopathological investigation revealed a perivascular accentuated inflammation with macrophages harboring PAS-positive diastase-resistant rods, which are distinctive features of cerebral Whipple disease. The patient received cotrimoxazole for 1 year postoperatively and recovered well. This case is exceptional because it represents an isolated cerebral manifestation of Whipple disease that presented as a solitary frontal tumor, thus raising the differential diagnosis of LGG. A review of diagnostic and therapeutic options in suspected cases is presented.
A transcranial approach for direct mechanical thrombectomy of dural sinus thrombosis
Authors: Chahlavi Ali , Steinmetz Michael P. , Masaryk Thomas J. , Rasmussen Peter A.
Published: May 2009

✓ Cerebral venous sinus thrombosis is often difficult to manage. Treatment options include systemically delivered anticoagulation therapy or chemical thrombolysis. Targeted endovascular delivery of thrombolytic agents is currently a popular option, but it carries an increased risk of hemorrhage. These strategies require significant time to produce thrombolysis, often in a patient with a rapidly deteriorating neurological condition. Rapid mechanical recanalization with thrombectomy is therefore very attractive; this procedure provides rapid recanalization with no increased risk of hemorrhage from use of thrombolytic agents. Nevertheless, the rheolytic catheter is large and stiff and may not be able to navigate tortuous intracranial vascular anatomy. The authors present their experience with direct dural sinus mechanical thrombectomy performed using the rheolytic catheter via a transcranial route.

Two patients with dural sinus thrombosis and rapidly deteriorating levels of consciousness underwent unsuccessful attempts at mechanical thrombolysis via the usual transfemoral route. Through a burr hole over the dural sinus, mechanical thrombectomy was subsequently performed using the thrombectomy catheter. Sinus patency was restored following treatment and both patients demonstrated neurological recovery.

Hemorrhage or a rapidly deteriorating neurological condition may preclude the use of systemic or locally delivered thrombolytic agents for the treatment of cerebral venous sinus thrombosis. Mechanical thrombectomy may be the treatment of choice in these circumstances. In patients with limited transfemoral access, a transcranial approach may be used to access the cerebral dural sinuses and thrombectomy may be safely and effectively performed. Further evaluation of this therapy is warranted.
Oculomotor palsy from an unruptured posterior communicating artery aneurysm presenting with cerebrospinal fluid pleocytosis and enhancement of the third cranial nerve
Authors: Kraus Robert R. , Kattah Jorge , Bortolotti Carlo , Lanzino Giuseppe
Published: May 2009

✓ The authors describe a patient with an unruptured posterior communicating artery aneurysm presenting with enhancement of the third cranial nerve on magnetic resonance (MR) imaging and cerebrospinal fluid (CSF) pleocytosis. Pathological entities associated with enhancement of the third cranial nerve on MR imaging are discussed and the authors speculate about the possible explanation for the CSF pleocytosis.
Evaluation of suprascapular nerve neurotization after nerve graft or transfer in the treatment of brachial plexus traction lesions
Authors: Malessy Martijn J. A. , de Ruiter Godard C. W. , de Boer Kees S. , Thomeer Ralph T. W. M.
Published: May 2009

Object.The aim of this retrospective study was to evaluate the restoration of shoulder function by means of suprascapular nerve neurotization in adult patients with proximal C-5 and C-6 lesions due to a severe brachial plexus traction injury. The primary goal of brachial plexus reconstructive surgery was to restore biceps muscle function and, secondarily, to reanimate shoulder function.

Methods.Suprascapular nerve neurotization was performed by grafting the C-5 nerve in 24 patients and by accessory or hypoglossal nerve transfer in 29 patients. Additional neurotization involving the axillary nerve was performed in 18 patients.

Postoperative needle electromyography studies of the supraspinatus, infraspinatus, and deltoid muscles showed signs of reinnervation in most patients; however, active glenohumeral shoulder function recovery was poor. In nine (17%) of 53 patients supraspinatus muscle strength was Medical Research Council (MRC) Grade 3 or 4 and in four patients (8%) infraspinatus muscle power was MRC Grade 3 or 4. In 18 patients in whom deltoid muscle reinnervation was attempted, MRC Grade 3 or 4 function was demonstrated in two (11%). In the overall group, eight patients (15%) exhibited glenohumeral abduction with a mean of 44 ± 17° (standard deviation [SD]; median 45°) and four patients (8%) exhibited glenohumeral exorotation with a mean of 48 ± 24° (SD; median 53°). In only three patients (6%) were both functions regained.

Conclusions.The reanimation of shoulder function in patients with proximal C-5 and C-6 brachial plexus traction injuries following suprascapular nerve neurotization is disappointingly low.
Relationship between intracranial pressure and other clinical variables in patients with aneurysmal subarachnoid hemorrhage
Authors: Heuer Gregory G. , Smith Michelle J. , Elliott J. Paul , Winn H. Richard , Leroux Peter D.
Published: May 2009

Object. Increased intracranial pressure (ICP) is well known to affect adversely patients with head injury. In contrast, the variables associated with ICP following aneurysmal subarachnoid hemorrhage (SAH) and their impact on outcome have been less intensely studied.

Methods. In this retrospective study the authors reviewed a prospective observational database cataloging the treatment details in 433 patients with SAH who had undergone surgical occlusion of an aneurysm as well as ICP monitoring. All 433 patients underwent postoperative ICP monitoring, whereas only 146 (33.7%) underwent both pre- and postoperative ICP monitoring.

The mean maximal ICP was 24.9 ± 17.3 mm Hg (mean ± standard deviation). During their hospital stay, 234 patients (54%) had elevated ICP (> 20 mm Hg), including 136 of those (48.7%) with a good clinical grade (Hunt and Hess Grades I–III) and 98 (63.6%) of the 154 patients with a poor grade (Hunt and Hess Grades IV and V) on admission. An increased mean maximal ICP was associated with several admission variables: worse Hunt and Hess clinical grade (p < 0.0001), a lower Glasgow Coma Scale (GSC) motor score (p < 0.0001); worse SAH grade based on results of computerized tomography studies (p < 0.0001); intracerebral hemorrhage (p = 0.024); severity of intraventricular hemorrhage (p < 0.0001); and rebleeding (p = 0.0048). Both intraoperative cerebral swelling (p = 0.0017) and postoperative GCS score (p < 0.0001) were significantly associated with a raised ICP. Variables such as patient age, aneurysm size, symptomatic vasospasm, intraoperative aneurysm rupture, and secondary cerebral insults such as hypoxia were not associated with raised ICP. Increased ICP adversely affected outcome: 71.9% of patients with normal ICP demonstrated favorable 6-month outcomes postoperatively, whereas 63.5% of patients with ICP between 20 and 50 mm Hg and 33.3% with ICP greater than 50 mm Hg demonstrated favorable outcomes. Among 21 patients whose raised ICP did not respond to mannitol therapy, all experienced a poor outcome and 95.2% died. Among 145 patients whose elevated ICP responded to mannitol, 66.9% had a favorable outcome and only 20.7% were dead 6 months after surgery (p < 0.0001). According to results of multivariate analysis, however, ICP was not an independent outcome predictor (odds ratio 1.26, 95% confidence interval 0.28–5.68).

Conclusions. Increased ICP is common after SAH, even in patients with a good clinical grade. Elevated ICP post-SAH is associated with a worse patient outcome, particularly if ICP does not respond to treatment. This association, however, may depend more on the overall severity of the SAH than on ICP alone.
Impact of stereotactic hematoma evacuation on activities of daily living during the chronic period following spontaneous putaminal hemorrhage: a randomized study
Authors: Hattori Naoyuki , Katayama Yoichi , Maya Yoshio , Gatherer Alexander
Published: May 2009

Object. Stereotactic evacuation of hematoma has been reported to reduce the incidence of mortality and to improve functional outcome in patients with spontaneous putaminal hemorrhage. Stereotactic evacuation of hematoma has not been widely accepted as a standard therapy, however, because its effect on functional outcome has been regarded as marginal and there have been no randomized trials with sufficient statistical power to quantify the benefits of this procedure. The authors reassessed the value of stereotactic evacuation of hematoma by analyzing its impact on activities of living during the chronic period following spontaneous putaminal hemorrhage in a randomized study.

Methods. Four hundred ninety patients were entered into the study. The severity of their hemorrhages was graded neurologically on admission (neurological grades: 1, eyes are open; 2, eyes are closed but open to weak stimuli; 3, eyes are closed but open to strong stimuli; 4, eyes do not open but extremities move to stimuli; and 5, eyes do not open and extremities do not move to stimuli). Patients with Grade 2 and those with Grade 3 were randomized into two groups with different treatment protocols (Group I, stereotactic evacuation of the hematoma; and Group II, conservative treatment). Patients assigned neurological Grade 4 or 5 were excluded from the study because a large-scale retrospective study in Japan revealed that surgical treatment in patients assigned to these neurological grades does not improve functional outcome. Among the 490 patients, 242 were randomized strictly. This patient population comprised 148 men and 94 women ranging in age from 38 to 80 years (mean 60.5 years).

Compared with Group II, Group I treatment resulted in a lower mortality rate and better recovery to functional independence in patients with neurological Grade 3. In patients with Grade 2, Group I treatment contributed to a better recovery of functional outcome and a lower mortality rate, but the difference was not significant. Multivariate analysis confirmed that stereotactic evacuation of the hematoma was contributory to a better recovery in functional outcome.

Conclusions. Stereotactic evacuation of hematoma is clearly of value in selected patients with spontaneous putuminal hemorrhage, whose eyes are closed but will open in response to strong stimuli (neurological Grade 3) on admission.
Proton magnetic resonance spectroscopy imaging in the evaluation of patients undergoing gamma knife surgery for Grade IV glioma
Authors: Chan Antoinette A. , Lau Aubrey , Pirzkall Andrea , Chang Susan M. , Verhey Lynn J. , Larson David , McDermott Michael W. , Dillon William P. , Nelson Sarah J.
Published: May 2009

Object. The purpose of this study was to assess the differences in spatial extent and metabolic activity in a comparison of a radiosurgical target defined by conventional strategies that utilize the enhancing lesion and a metabolic lesion defined by proton magnetic resonance spectroscopy (MRS) imaging. The authors evaluated whether these differences manifest themselves in the clinical outcome of patients and assessed the value of incorporating 1H-MRS imaging—derived spatial information into the treatment planning process for gamma knife surgery (GKS).

Methods. Twenty-six patients harboring Grade IV gliomas who had previously been treated with external-beam radiation therapy were evaluated by comparing the radiosurgically treated lesion volume with the volume of metabolically active tumor defined on 1H-MRS imaging. The cohort was evenly divided into two groups based on the percentage of overlap between the radiosurgical target and the metabolic lesion volumes. Patients with a percentage of overlap greater than 50% with respect to the metabolic lesion volume were classified as low risk and those with an overlap less than 50% were classified as high risk.

Kaplan—Meier estimators were calculated using time to progression and survival as dependent variables. The metabolite levels within the metabolic lesion were significantly greater than those within the radiosurgical target (p ≤ 0.001). The median survival was 15.7 months for patients in the low-risk group and 10.4 months for those in the highrisk group. This difference was statistically significant (p < 0.01).

Conclusions. Analysis of the results of this study indicates that patients undergoing GKS may benefit from the inclusion of 1H-MRS imaging in the treatment planning process.
Combined use of 18F-fluorodeoxyglucose and 11C-methionine in 45 positron emission tomography—guided stereotactic brain biopsies
Authors: Pirotte Benoit , Goldman Serge , Massager Nicolas , David Philippe , Wikler David , Lipszyc Maurice , Salmon Isabelle , Brotchi Jacques , Levivier Marc
Published: May 2009

Object.The aim of this study was to compare the contribution of the tracers11C-methionine (Met) and18F-fluorodeoxyglucose (FDG) in positron emission tomography (PET)—guided stereotactic brain biopsy.

Methods.Forty-five patients underwent combined Met-PET and FDG-PET studies associated with computerized tomography (CT)— or magnetic resonance (MR)—guided stereotactic biopsy. Each patient presented with a lesion that was in proximity to the cortical or subcortical gray matter. The Met-PET and FDG-PET scans were analyzed to determine which tracer offers the best information to guide at least one stereotactic biopsy trajectory. Histologically based diagnoses were rendered in all patients (39 tumors, six nontumorous lesions) and biopsies were performed in all tumors with the aid of PET guidance. When tumor FDG uptake was higher than that in the gray matter (18 tumors), FDG was used for target definition. When FDG uptake was absent or equivalent to that in the gray matter (21 tumors), Met was used for target definition. Parallel review of all histological and imaging data showed that all tumors had an area of abnormal Met uptake and 33 had abnormal FDG uptake. All six nontumorous lesions had no Met uptake and biopsies were performed using CT or MR guidance only. All tumor trajectories had an area of abnormal Met uptake; all nondiagnostic trajectories in tumors had no abnormal Met uptake.

Conclusions.When FDG shows limitations in target selection, Met is a good alternative because of its high specificity in tumors. Moreover, in the context of a single-tracer procedure and regardless of FDG uptake, Met is a better choice for PET guidance in neurosurgical procedures.
Comparison of the transvermian and telovelar approaches to the fourth ventricle
Authors: Tanriover Necmettin , Ulm Arthur J. , Rhoton Albert L. , Yasuda Alexandre
Published: May 2009

Object. The two most common surgical routes to the fourth ventricle are the transvermian and telovelar approaches. The purpose of this study was to compare the microanatomy and exposures gained through these approaches.

Methods. Ten formalin-fixed specimens were dissected in a stepwise manner to simulate the transvermian and telovelar surgical approaches. Stealth image guidance was used to compare the exposures and working angles obtained using these approaches.

The transvermian and telovelar approaches provided access to the entire rostrocaudal length of the fourth ventricle floor from the aqueduct to the obex. In addition, both approaches provided access to the entire width of the floor of the fourth ventricle. The major difference between the two approaches regarded the exposure of the lateral recess and the foramen of Luschka. The telovelar, but not the transvermian, approach exposed the lateral and superolateral recesses and the foramen of Luschka. The transvermian approach, which offered an incision through at least the lower third of the vermis, afforded a modest increase in the operator's working angle compared with the telovelar approach when accessing the rostral half of the fourth ventricle.

Conclusions. The transvermian approach provides slightly better visualization of the medial part of the superior half of the roof of the fourth ventricle. The telovelar approach, which lacks incision of any part of the cerebellum, provides an additional exposure to the lateral recesses and the foramen of Luschka.
Effects of hyperbaric oxygen therapy on cerebral oxygenation and mitochondrial function following moderate lateral fluid-percussion injury in rats
Authors: Daugherty Wilson P. , Levasseur Joseph E. , Sun Dong , Rockswold Gaylan L. , Bullock M. Ross
Published: May 2009

Object. In the current study, the authors examined the effects of hyperbaric O2 (HBO) following fluid-percussion brain injury and its implications on brain tissue oxygenation (PO2) and O2 consumption (VO2) and mitochondrial function (redox potential).

Methods. Cerebral tissue PO2 was measured following induction of a lateral fluid-percussion brain injury in rats. Hyperbaric O2 treatment (100% O2 at 1.5 ata) significantly increased brain tissue PO2 in both injured and sham-injured animals. For VO2 and redox potential experiments, animals were treated using 30% O2 or HBO therapy for 1 or 4 hours (that is, 4 hours 30% O2 or 1 hour HBO and 3 hours 100% O2). Microrespirometer measurements of VO2 demonstrated significant increases following HBO treatment in both injured and sham-injured animals when compared with animals that underwent 30% O2 treatment. Mitochondrial redox potential, as measured by Alamar blue fluorescence, demonstrated injury-induced reductions at 1 hour postinjury. These reductions were partially reversed at 4 hours postinjury in animals treated with 30% O2 and completely reversed at 4 hours postinjury in animals on HBO therapy when compared with animals treated for only 1 hour.

Conclusions. Analysis of data in the current study demonstrates that HBO significantly increases brain tissue PO2 after injury. Nonetheless, treatment with HBO was insufficient to overcome injury-induced reductions in mitochondrial redox potential at 1 hour postinjury but was able to restore redox potential by 4 hours postinjury. Furthermore, HBO induced an increase in VO2 in both injured and sham-injured animals. Taken together, these data demonstrate that mitochondrial function is depressed by injury and that the recovery of aerobic metabolic function may be enhanced by treatment with HBO.
Suprapineal recess: an alternate site for third ventriculostomy?
Authors: Daniel Roy Thomas , Lee Gabriel Yin Foo , Reilly Peter Lawrence
Published: May 2009

✓ This 30-year-old woman presented with clinical symptoms and signs of intracranial hypertension and Parinaud syndrome secondary to ventriculoperitoneal shunt dysfunction. Magnetic resonance (MR) imaging revealed gross triventricular hydrocephalus with a large suprapineal recess due to aqueductal stenosis. Using an endoscopic approach, a ventriculostomy was performed within the floor of the dilated suprapineal recess. Following this procedure the patient experienced alleviation of all her neurological symptoms and signs. Postoperative MR imaging and cerebrospinal fluid flow studies demonstrated a functioning ventriculostomy. The anatomy of the suprapineal recess and its suitability for endoscopic ventriculostomy are discussed.
Transition from meningeal melanocytoma to primary cerebral melanoma
Authors: Roser Florian , Nakamura Makoto , Brandis Almuth , Hans Volkmar , Vorkapic Peter , Samii Madjid
Published: May 2009

✓ The authors describe the first case of an intracranial transition of a melanocytoma into a primary malignant melanoma within a short time. A 37-year-old woman presented with progressive brainstem syndrome due to a tumor, originally diagnosed and treated 12 years earlier, that extended from the petroclival area to the anterior craniocervical junction. The histological workup following subtotal tumor resection of the initial tumor had revealed the typical features of a fibrous melanocytic meningioma without increased proliferation. Ten years after the patient had completed treatment for the melanocytic meningioma, control neuroimaging demonstrated growth of the residual tumor with compression of the brainstem. Another neurosurgical intervention revealed a dark tumor of hard consistency. At this time immunohistochemical examinations demonstrated melanocytic features (expression of vimentin, S100 protein, and melan A) of the lesion with focally increased proliferation (5% of Ki-67—positive cells) but no higher mitotic activity. Clinical signs of deterioration along with imaging-confirmed tumor progression precipitated another operation within 7 months. A neuropathological examination revealed epithelial and anaplastic changes and indicated that the MIB-1 indices were greater than 25%. Pleomorphic changes and a focal high mitotic activity led to the diagnosis of a primary cerebral malignant melanoma. The patient's later clinical course consisted of a rapid diffuse meningeal spread of the lesion throughout the entire brain and spine. Despite whole-brain and stereotactic radiation therapy as well as chemotherapy, the patient died 4 months after the last neuropathological diagnosis. Although grossly resembling a meningioma, melanocytomas lack the former's histological and immunohistochemical features. The biological behavior of a melanocytoma is variable and recurrence may happen after subtotal resection, but intracranial transition into a malignant melanoma has not been observed previously.