bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracranial Castleman's disease of solitary form
Authors: Hashimoto Hiroyuki , Iida Jun-ichi , Hironaka Yasuo , Sakaki Toshisuke 
Published: May 2009

✓ This 62-year-old woman presented with clumsiness in her right hand. Magnetic resonance imaging demonstrated a small lesion mimicking a meningioma, which had arisen from the tentorium and contained notable edema.Full recovery was achieved by total removal of the lesion, which was diagnosed as a lymphoid mass resembling giant lymph node hyperplasia on histological examination. The lack of notable findings on whole-body and laboratory studies was compatible with a rare case of intracranial Castleman's disease of solitary form. The authors document clinical, neuroradiological, and pathological features of this rare disease.
Thalamic stimulation and functional magnetic resonance imaging: localization of cortical and subcortical activation with implanted electrodes
Authors: Rezai Ali R. , Lozano Andres M. , Crawley Adrian P. , Joy Michael L. G. , Davis Karen D. , Kwan Chun L. , Dostrovsky Jonathan O. , Tasker Ronald R. , Mikulis David J. 
Published: May 2009

✓ The utility of functional magnetic resonance (fMR) imaging in patients with implanted thalamic electrodes has not yet been determined. The aim of this study was to establish the safety of performing fMR imaging in patients with thalamic deep brain stimulators and to determine the value of fMR imaging in detecting cortical and subcortical activity during stimulation.Functional MR imaging was performed in three patients suffering from chronic pain and two patients with essential tremor. Two of the three patients with pain had undergone electrode implantation in the thalamic sensory ventralis caudalis (Vc) nucleus and the other had undergone electrode implantation in both the Vc and the periventricular gray (PVG) matter. Patients with tremor underwent electrode implantation in the ventralis intermedius (Vim) nucleus. Functional MR imaging was performed during stimulation by using a pulse generator connected to a transcutaneous extension lead. Clinically, Vc stimulation evoked paresthesias in the contralateral body, PVG stimulation evoked a sensation of diffuse internal body warmth, and Vim stimulation caused tremor arrest.Functional images were acquired using a 1.5-tesla MR imaging system. The Vc stimulation at intensities provoking paresthesias resulted in activation of the primary somatosensory cortex (SI). Stimulation at subthreshold intensities failed to activate the SI. Additional stimulation-coupled activation was observed in the thalamus, the secondary somatosensory cortex (SII), and the insula. In contrast, stimulation of the PVG electrode did not evoke paresthesias or activate the SI, but resulted in medial thalamic and cingulate cortex activation. Stimulation in the Vim resulted in thalamic, basal ganglia, and SI activation.An evaluation of the safety of the procedure indicated that significant current could be induced within the electrode if a faulty connecting cable (defective insulation) came in contact with the patient. Simple precautions, such as inspection of wires for fraying and prevention of their contact with the patient, enabled the procedure to be conducted safely. Clinical safety was further corroborated by performing 86 MR studies in patients in whom electrodes had been implanted with no adverse clinical effects.This is the first report of the use of fMR imaging during stimulation with implanted thalamic electrodes. The authors' findings demonstrate that fMR imaging can safely detect the activation of cortical and subcortical neuronal pathways during stimulation and that stimulation does not interfere with imaging. This approach offers great potential for understanding the mechanisms of action of deep brain stimulation and those underlying pain and tremor generation.
Five-year experience in using coil embolization for ruptured intracranial aneurysms: outcomes and incidence of late rebleeding
Authors: Byrne James V. , Sohn Min-Joo , Molyneux Andrew J. 
Published: May 2009

Object. During a 5-year period 317 patients presenting with aneurysmal subarachnoid hemorrhage were successfully treated by coil embolization within 30 days of hemorrhage. The authors followed patients to assess the stability of aneurysm occlusion and its longer-term efficacy in protecting patients against rebleeding.Methods. Patients were followed for 6 to 65 months (median 22.3 months) by clinical review, angiography performed at 6 months posttreatment, and annual questionnaires. Stable angiographic occlusion was evident in 86.4% of small and 85.2% of large aneurysms with recurrent filling in 38 (14.7%) of 259 aneurysms. Rebleeding was caused by aneurysm recurrence in four patients (between 11 and 35 months posttreatment) and by rupture of a coincidental untreated aneurysm in one patient. Annual rebleeding rates were 0.8% in the 1st year, 0.6% in the 2nd year, and 2.4% in the 3rd year after aneurysm embolization, with no rebleeding in subsequent years. Rebleeding occurred in three (7.9%) of 38 recurrent aneurysms and in one (0.4%) of 221 aneurysms that appeared stable on angiography.Conclusions. Periodic follow-up angiography after coil embolization is recommended to identify aneurysm recurrence and those patients at a high risk of late rebleeding.
A simple relationship between radiological arteriovenous malformation hemodynamics and clinical presentation: a prospective, blinded analysis of 31 cases
Authors: Norris John S. , Valiante Taufik A. , Wallace M. Christopher , Willinsky Robert A. , Montanera Walter J. , terBrugge Karel G. , Tymianski Michael 
Published: May 2009

Object. The authors sought to establish prospectively whether there is a simple relationship between radiological features of brain arteriovenous malformation (AVM) hemodynamics and a patient's clinical presentation.Methods. Thirty-one consecutive patients with AVMs underwent cerebral angiography at 3.8 frames/second during each standardized injection of contrast material. Contrast dilution curves were derived from the image sequences by using regions of interest (ROIs) traced on arteries feeding and veins draining the AVM nidus. Angiographic parameters were then analyzed in a blinded fashion. These parameters included the times required to reach the peak contrast density, the contrast decay time, and fractions thereof, in the ROI for each vessel. The authors determined whether these parameters, the arteriovenous transit time, and/or AVM size were related to patients' presentation with hemorrhage (11 patients), seizure (11 patients), or other clinical symptoms (nine patients). Statistically significant results were found only in analyses of arterial phase times to reach peak contrast density. Analyses of venous parameters, AVM size, and nidus transit time showed trends but no statistical significance. Arterial filling with contrast material was significantly slower in patients presenting with hemorrhage (mean 50%, 80%, and 100% of time to peak ± standard error [SE] = 1.19 ± 0.13, 1.97 ± 0.18, and 3.04 ± 0.34 seconds, respectively) compared with patients presenting with seizures (mean 50%, 80%, and 100% of time to peak ± SE = 0.80 ± 0.12, 1.32 ± 0.18, and 1.95 ± 0.29 seconds, respectively) according to analysis of variance (p < 0.05) and post-hoc t-tests (p < 0.05) for each parameter. Patients who presented with other symptoms had intermediate arterial filling times.Conclusions. These simple hemodynamic parameters, which can be obtained without added risk to the patient, may help identify a subset of individuals in whom AVMs pose a higher risk of future hemorrhage and who may therefore warrant more expeditious treatment.
Topographic anatomy of the insular region
Authors: Türe Uğur , Yaşargil Dianne C. H. , Al-Mefty Ossama , Yaşargil M. Gazi 
Published: May 2009

Object. The insula is one of the paralimbic structures and constitutes the invaginated portion of the cerebral cortex, forming the base of the sylvian fissure. The authors provide a detailed anatomical study of the insular region to assist in the process of conceptualizing a reliable surgical approach to allow for a successful course of surgery.Methods. The topographic anatomy of the insular region was studied in 25 formalin-fixed brain specimens (50 hemispheres). The periinsular sulci (anterior, superior, and inferior) define the limits of the frontoorbital, frontoparietal, and temporal opercula, respectively. The opercula cover and enclose the insula. The limen insula is located in the depths of the sylvian fissure and constitutes the anterobasal portion of the insula. A central insular sulcus divides the insula into two portions, the anterior insula (larger) and the posterior insula (smaller). The anterior insula is composed of three principal short insular gyri (anterior, middle, and posterior) as well as the accessory and transverse insular gyri. All five gyri converge at the insular apex, which represents the most superficial aspect of the insula. The posterior insula is composed of the anterior and posterior long insular gyri and the postcentral insular sulcus, which separates them. The anterior insula was found to be connected exclusively to the frontal lobe, whereas the posterior insula was connected to both the parietal and temporal lobes. Opercular gyri and sulci were observed to interdigitate within the opercula and to interdigitate the gyri and sulci of the insula. Using the fiber dissection technique, various unique anatomical features and relationships of the insula were determined.Conclusions. The topographic anatomy of the insular region is described in this article, and a practical terminology for gyral and sulcal patterns of surgical significance is presented. This study clarifies and supplements the information presently available to help develop a more coherent surgical concept.
Complex right hemisphere developmental venous anomaly associated with multiple facial hemangiomas
Authors: Aagaard Beverly D. L. , Song Joon K. , Eskridge Joseph M. , Mayberg Marc R. 
Published: May 2009

✓ Complex developmental venous anomalies (DVAs) represent variations of normal cerebral venous drainage and consist of dilation of the superficial and/or deep venous system. These rare anomalies can occur unilaterally or bilaterally, supratentorially or infratentorially, focally or they can affect the entire hemisphere. Some DVAs are associated with cervicofacial venous malformations or facial lymphatic malformations. Anomalies of this type are generally clinically silent, and cerebral dysfunction is usually absent. Symptoms, when they occur, are most commonly headache or mild seizure disorders. The angiographic findings are striking, with well-formed but enlarged transcerebral medullary and deep and/or superficial cortical veins. Opacification of these venous structures occurs within the same time frame as a normal angiographic venous phase.The authors report the case of a 33-year-old man in whom a large inoperable arteriovenous malformation had been previously diagnosed and who presented with seizures. Repeated magnetic resonance imaging and angiography demonstrated abnormally dilated transcerebral, superficial, and deep venous structures involving the entire right hemisphere with no identifiable nidus. Additionally, multiple bilateral benign facial hemangiomas were present in this patient.It is important to recognize this rare venous appearance as a developmental variant and not mistake it for an arteriovenous malformation or a partially thrombosed vein of Galen malformation. Because these venous anomalies are extreme variants of the normal venous system, hemorrhage rarely, if ever, occurs and the patient can be reassured that no interventional or surgical therapy is necessary or warranted.
Endovascular treatment of multiple intracranial aneurysms by using Guglielmi detachable coils
Authors: Solander Sten , Ulhoa Alexandre , Viñuela Fernando , Duckwiler Gary R. , Gobin Y. Pierre , Martin Neil A. , Frazee John G. , Guglielmi Guido 
Published: May 2009

Object. The purpose of this paper is to present the authors' experience with Guglielmi detachable coil (GDC) embolization of multiple intracranial aneurysms and to evaluate the results of this therapy in single-stage procedures.Methods. Clinical and angiographic evaluations were performed in 38 consecutive patients with multiple intracranial aneurysms treated by GDC embolization between March 1990 and October 1997. Twenty-nine patients presented with subarachnoid hemorrhage (SAH), four with mass effect, and five were asymptomatic. These 38 patients harbored 101 aneurysms, 79 of which were treated with GDCs, 14 by surgical clipping, and eight were left untreated. Of the GDC-treated lesions, a complete endovascular occlusion was achieved in 55 aneurysms (70%), and 24 (30%) presented neck remnants. Twenty-five patients (66%) underwent GDC embolization of more than one aneurysm in the first session. Eighteen (86%) of 21 patients with acute SAH underwent treatment for all aneurysms within 3 days after admission (15 of 21 in one session). Follow-up angiographic studies in 30 patients demonstrated an unchanged or improved result in 94% of the aneurysms (59 lesions) and coil compaction in 6% (four lesions). The overall clinical outcome was excellent in 34 patients (89%), good in one (3%), fair in one (3%), and death in two (5%).Conclusions. Endovascular treatment of multiple intracranial aneurysms, regardless of their location, with GDCs was performed safely in one session, even during the acute phase of SAH. Treatment of all aneurysms in one session protected the patient from rebleeding and eliminated the risk of mistakenly treating only the unruptured aneurysms.
Lack of correlation between neuronal hyperexcitability and electrocorticographic responsiveness in epileptogenic human neocortex
Authors: Telfeian Albert E. , Spencer Dennis D. , Williamson Anne 
Published: May 2009

Object. The purpose of this study was to determine whether intrinsic neuronal properties and synaptic responses differed between interictally active and inactive tissue removed in neocortical resections from patients undergoing surgical treatment for epilepsy.Methods. Whole-cell patch recordings were performed in layer 2 or 3 and layer 5 pyramidal cells in neocortical slices obtained from tissue surgically removed from patients for the treatment of medically intractable seizures. Synaptic responses to stimulation at the layer 6—white matter border were used to classify cells as nonbursting if they responded with only a single action potential for all above-threshold stimuli (80%). These responses were usually followed by biphasic inhibitory postsynaptic potentials (IPSPs). Cells were classified as bursting if they fired at least three action potentials in response to synaptic stimulation (20%). These cells typically showed no IPSPs and responded in either an all-or-nothing or graded fashion. Approximately twice as many cells at layer 2 or 3 (29%) than cells at layer 5 (14%) fired synaptic bursts. Synaptic bursting was not associated with an alteration in a cell's response properties to γ-aminobutyric acid. It was notable that, in tissue samples determined by electrocorticography (ECoG) to be either interictally active or not active, the proportion of cells that burst was exactly the same in both groups (24%). We found no cells with intrinsic burst firing.Conclusions. We conclude that synaptic bursting was characteristic of a small proportion of cells from epileptic tissue; however, this did not correlate with interictal spikes on ECoG.
Anatomical and functional connectivity of the transected ulnar nerve after intercostal neurotization in cats
Authors: Isla Alberto , Bejarano Bartolomé , Morales Carmen , Conde Concepción Pérez , Avendaño Carlos 
Published: May 2009

Object. Acute transfer of three intercostal nerves to the ulnar nerve was performed in cats for histological and clinical evaluation of a distal muscle reinnervation.Methods. Infraclavicular intercostal-ulnar communications were created after dividing the motor branches of the upper intercostal nerves in 14 adult cats. Reinnervation of distal forelimb muscles in the ulnar territory was assessed by electromyographic (EMG) studies and motor function rating each month until 18 months postsurgery. In five of these treated animals, and in four controls, horseradish peroxidase (HRP) was applied to the ulnar or intercostal nerves to study the amount and distribution of retrograde motor neuron labeling in the spinal cord. Also, samples of reinnervated muscles and neurotized ulnar nerves were processed to assess regeneration.Simple ulnar transection without reconstruction led to permanent atrophy of ulnar muscles, lack of recovery according to EMG or clinical studies, and disappearance of the ulnar motor neuron pool. In contrast, ulnar neurotization with the intercostal nerves led to a high rate of functional recovery, which began 5 months postsurgery, and progressed from muscle activity synchronized with ventilatory movements to spontaneous movements that were independent of respiration. This recovery was accompanied by substantial retrograde labeling of intercostal motor neurons after HRP application in the ulnar nerve. Cell counts showed that practically the whole motor neuron pool of the involved intercostal nerves contributed to reinnervation of the transected ulnar nerve.Conclusions. These findings demonstrate that the use of intercostal nerves to neurotize long brachial plexus nerves can achieve long-lasting and successful reinnervation of distal forelimb muscles.
Mitogen-activated protein kinase mediation of hemolysate-induced contraction in rabbit basilar artery
Authors: Zubkov Alexander Y. , Ogihara Kotaro , Tumu Phani , Patlolla Anita , Lewis Adam I. , Parent Andrew D. , Zhang John 
Published: May 2009

Object. Mitogen-activated protein kinase (MAPK) is an important signaling factor in vascular proliferation and contraction, which are the two features of cerebral vasospasm that follow subarachnoid hemorrhage. The authors studied the possible involvement of MAPK in hemolysate-induced signal transduction and contraction in rabbit basilar artery (BA).Methods. Isometric tension was used to record the contractile response of rabbit BA to hemolysate, and Western blots were obtained using antibodies for MAPK.The following results are reported. 1) Hemolysate produced a concentration-dependent contraction of rabbit BA; however, preincubation of arteries with the MAPK kinase (MEK) inhibitor PD-98059 markedly reduced this contraction. The administration of PD-98059 also relaxed, in a concentration-dependent fashion, the sustained contraction induced by 10% hemolysate. 2) The Janus tyrosine kinase 2 inhibitor AG-490, preincubated with arterial rings, reduced the contractile response to hemolysate but failed to relax the sustained contraction induced by this agent. The Src-tyrosine kinase inhibitor damnacanthal and the phosphatidylinositol 3—kinase inhibitor wortmannin failed to reduce hemolysate-induced contraction. 3) Hemolysate produced a time-dependent elevation of MAPK immunoreactivity as seen on Western blots of rabbit BA. The MAPK was enhanced 1 minute after hemolysate exposure and the effect reached maximum levels at 5 minutes. The immunoreactivity of MAPK decayed slowly over time, but the level of this kinase was still higher than the basal level, even at 2 hours after exposure to hemolysate. Preincubation of arteries with the MEK inhibitor PD-98059 abolished the effect of hemolysate on MAPK immunoreactivity.Conclusions. Hemolysate produced contraction of rabbit BA, possibly by activation of MAPK, and therefore MAPK inhibitors may be useful in the treatment of cerebral vasospasm.
Experience with a programmable valve shunt system
Authors: Yamashita Nobuko , Kamiya Ken , Yamada Kazuo 
Published: May 2009

Object. The goal of this study was to clarify the efficacy of the Codman Hakim programmable valve. Clinical data obtained in 179 patients with hydrocephalus or other intracranial fluid—accumulating diseases were analyzed.Methods. Shunt placement operations were effective in 168 patients, approximately one half (50.6%) of whose devices required reprogramming of opening pressure postoperatively. This was a significantly larger number of shunts than the authors had thought would need reprogramming. Extremely narrowed ventricles observed on computerized tomography scans, as well as clinical symptoms related to inadequate or excessive cerebrospinal fluid drainage, improved in patients after shunt reprogramming. Shunt reprogramming frequently was necessary in patients with posthemorrhagic acute hydrocephalus; the programmable valve proved particularly beneficial for such patients. Subdural effusion and arachnoid cyst also proved to be good indications for use of the valve. Twelve patients (7%) suffered complications postoperatively. The most common complication was valve obstruction, which occurred in five patients, most of whom had brain tumors.Conclusions. The programmable valve was beneficial for the treatment of hydrocephalus and other intracranial fluid—accumulating diseases. It is important to be careful in selecting patients for treatment with the programmable valve, because complications involving the valve seem more likely in brain tumor cases. The valve proved to be poorly resistant to magnetic fields; therefore, it is essential to confirm opening pressure after every magnetic resonance imaging examination. The authors recommend that an identification system for patients be developed so that medical personnel will be aware of the presence of the valve and the previous setting of opening pressure.
Functional neuronavigation with magnetoencephalography: outcome in 50 patients with lesions around the motor cortex
Authors: Ganslandt Oliver , Fahlbusch Rudolf , Nimsky Christopher , Kober Helmut , Möller Martin , Steinmeier Ralf , Romstöck Johann , Vieth Jürgen 
Published: May 2009

Object. The authors conducted a study to evaluate the clinical outcome in 50 patients with lesions around the motor cortex who underwent surgery in which functional neuronavigation was performed.Methods. The sensorimotor cortex was identified in all patients with the use of magnetoencephalography (MEG). The MEG-source localizations were superimposed onto a three-dimensional magnetic resonance image and the image data set was implemented into a neuronavigation system. Based on this setup, the surgeon chose the best surgical strategy. During surgery, the pre- and postcentral gyri were identified by neuronavigation and, in addition, the central sulcus was localized using intraoperative recording of somatosensory evoked potentials. In all cases MEG localizations of the sensory or motor cortex were correct. In 30% of the patients preoperative paresis improved, in 66% no additional deficits occurred, and in only 4% (two patients) deterioration of neurological function occurred. In one of these patients the deterioration was not related to the procedure.Conclusions. The method of incorporating functional data into neuronavigation systems is a promising tool that can be used in more radical surgery to lessen morbidity around eloquent brain areas.