Showing papers in "Journal of Neurosurgery in 2004"
TL;DR: There is an urgent need for randomized, controlled, long-term studies on the efficacy of SCS involving larger patient sample sizes and, in general, SCS was a safe and effective treatment for a variety of chronic neuropathic conditions.
Abstract: Object. The purpose of this report was to examine the available literature to determine the safety and efficacy of spinal cord stimulation (SCS) for the treatment of chronic pain of the trunk and limbs. Methods. The author identified 68 studies that fulfilled the efficacy inclusion/exclusion criteria, grouped on the basis of pain indication, with an overall population of 3679 patients. Fifty-one studies fulfilled all safety inclusion/exclusion criteria. Based on the literature review, the author found that SCS had a positive, symptomatic, long-term effect in cases of refractory angina pain, severe ischemic limb pain secondary to peripheral vascular disease, peripheral neuropathic pain, and chronic low-back pain, and that, in general, SCS was a safe and effective treatment for a variety of chronic neuropathic conditions. Conclusions. Despite the positive findings, there is an urgent need for randomized, controlled, long-term studies on the efficacy of SCS involving larger patient sample sizes.
698 citations
TL;DR: Following pial synangiosis, the majority of pediatric patients with moyamoya syndrome stop having strokes and TIAs, and they appear to experience an excellent long-term prognosis.
Abstract: Object. Moyamoya syndrome, a narrowing of the basal intracranial vessels accompanied by the development of a cloud of collateral “moyamoya” vasculature, causes cerebral ischemia and stroke. This study was undertaken to determine if a standardized neurosurgical revascularization procedure, pial synangiosis, conferred long-term benefit in pediatric patients. Methods. The authors reviewed the clinical and radiographic records obtained in a consecutive series of patients with moyamoya syndrome. Patients were 21 years of age or younger and underwent surgery performed by a single neurosurgeon during a 17-year period. There were 143 patients (89 females and 54 males). Sixteen patients were Asian. Neurofibromatosis was present in 16 patients, 13 had undergone therapeutic cranial irradiation, and Down syndrome was present in 10. In 66 there was no known predisposing condition. Stroke had occurred in 67.8% of the population and transient ischemic attacks (TIAs) in 43.4% prior to surgery. Within the first 30 days following 271 craniotomies for pial synangiosis, there were 11 episodes of stroke (7.7% per patient; 4% per surgically treated hemisphere) and three severe TIAs. Follow-up evaluation was performed in all but one patient (mean period 5.1 years). In 126 patients followed for more than 1 year, four suffered a late-onset stroke, one suffered a severe reversible TIA without magnetic resonance imaging‐documented evidence of stroke, and two experienced persistent TIAs. In 46 patients followed for more than 5 years in whom the major initial presentation was stroke alone, only two late-onset strokes have occurred. Functional status at the time of surgery determined long-term functional status. Conclusions. Following pial synangiosis, the majority of pediatric patients with moyamoya syndrome stop having strokes and TIAs, and they appear to experience an excellent long-term prognosis.
484 citations
TL;DR: Joint distraction and firm lateral mass fixation in selected cases of basilar Invagination is a reasonable surgical treatment for reducing the basilar invagination, restoring craniospinal alignment, and establishing fixation of the atlantoaxial joint.
Abstract: Object. The author discusses the successful preliminary experience of treating selected cases of basilar invagination by performing atlantoaxial joint distraction, reduction of the basilar invagination, and direct lateral mass atlantoaxial plate/screw fixation. Methods. Twenty-two patients with basilar invagination—in which the odontoid process invaginated into the foramen magnum and the tip of the odontoid process was above the Chamberlain, McRae foramen magnum, and Wackenheim clival lines—were selected to undergo surgery. In all patients fixed atlantoaxial dislocations were documented. The 16 male and six female patients ranged in age from 8 to 50 years. A history of trauma prior to the onset of symptoms was documented in 17 patients. Following surgery, the author observed minimal-to-significant reduction of basilar invagination and alteration in other craniospinal parameters resulting in restoration of alignment of the tip of the odontoid process and the clivus and the entire craniovertebral junction i...
403 citations
TL;DR: Electrical stimulation of the GPi is an effective, reversible, and adaptable treatment for PGD and should be considered for conditions refractory to pharmaceutical therapies.
Abstract: Object. Primary generalized dystonia (PGD) is a medically refractory disease of the brain causing twisting or spasmodic movements and abnormal postures. In more than 30% of cases it is associated with the autosomal DYT1 mutation. Continuous electrical stimulation of the globus pallidus internus (GPi) has been used successfully in the treatment of PGD. The aim of this study was to examine the long-term efficacy and safety of deep brain stimulation (DBS) in the treatment of PGD in children and adults with and without the DYT1 mutation. Methods. Thirty-one patients with PGD were selected for surgery. Electrodes were bilaterally implanted under stereotactic guidance and connected to neurostimulators that were inserted subcutaneously. Efficacy was evaluated by comparing scores on the clinical and functional Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) before and after implantation. The efficacy of stimulation improved with time. After 2 years, compared with preoperative values, the mean (� standard deviation) clinical and functional BFMDRS scores had improved by 79 � 19% and 65 � 33%, respectively. At the 2-year follow-up examination the improvement was comparable in patients with and without the DYT1 mutation in both the functional (p = 0.12) and clinical (p = 0.33) scores. Children displayed greater improvements in the clinical score than adult patients (p = 0.04) at 2 years of follow up. In contrast, there was no significant difference in functional scores between children and adults (p = 0.95). Conclusions. Electrical stimulation of the GPi is an effective, reversible, and adaptable treatment for PGD and should be considered for conditions refractory to pharmaceutical therapies.
381 citations
TL;DR: In patients with gliomas that are located within or adjacent to the rolandic cortex and, thus, the descending motor tracts, stimulation mapping of subcortical pathways enables the surgeon to identify these descending motor pathways during tumor removal and to achieve an acceptable rate of permanent morbidity in these high-risk functional areas.
Abstract: Object. Intraoperative stimulation mapping of subcortical white matter tracts during the resection of gliomas has become a valuable surgical adjunct that is used to reduce morbidity associated with tumor removal. The purpose of this retrospective analysis was to assess the morbidity and functional outcome associated with this method, thus allowing the surgeon to predict the likelihood of causing a temporary or permanent motor deficit. Methods. In this study, the authors report their experience with intraoperative stimulation mapping to locate subcortical motor pathways in 294 patients who underwent surgery for hemispheric gliomas within or adjacent to the rolandic cortex. Data were collected regarding intraoperative cortical and subcortical stimulation mapping results, along with the patient's neurological status pre- and postoperatively. For patients in whom an additional motor deficit occurred postoperatively, its evolution was examined. Of 294 patients, an additional postoperative motor deficit occurre...
355 citations
TL;DR: It is suggested that CED of paclitaxel in patients with recurrent malignant gliomas is associated with a high antitumor response rate, although it is associatedWith a significant incidence of treatment-associated complications.
Abstract: Object. A minority of patients with recurrent glioblastomas multiforme (GBMs) responds to systemic chemotherapy. The authors investigated the safety and efficacy of intratumoral convection-enhanced delivery (CED) of paclitaxel in patients harboring histologically confirmed recurrent GBMs and anaplastic astrocytomas. Methods. Fifteen patients received a total of 20 cycles of intratumoral CED of paclitaxel. The patients were observed daily by performing diffusion-weighted (DW) magnetic resonance (MR) imaging to assess the convective process and routine diagnostic MR imaging to identify the tumor response. Effective convection was determined by the progression of the hyperintense signal within the tumor on DW MR images, which corresponded to a subsequent lytic tumor response displayed on conventional MR images. Of the 15 patients, five complete responses and six partial responses were observed, giving a response rate of 73%. The antitumor effect was confirmed by one biopsy and three en bloc resections of tum...
319 citations
TL;DR: It is postulate that lateral saccular aneurysms located on more curved arteries are subjected to higher hemodynamic stresses, and the large impact zone at the distal side of theAneurysm neck correlates well with other findings, implicating this zone as the most likely site of aneurYSm growth or regrowth of treated lesions.
Abstract: Object. Few researchers have quantified the role of arterial geometry in the pathogenesis of saccular cerebral aneurysms. The authors investigated the effects of parent artery geometry on aneurysm hemodynamics and assessed the implications relative to aneurysm growth and treatment effectiveness. Methods. The hemodynamics of three-dimensional saccular aneurysms arising from the lateral wall of arteries with varying arterial curves (starting with a straight vessel model) and neck sizes were studied using a computational fluid dynamics analysis. The effects of these geometric parameters on hemodynamic parameters, including flow velocity, aneurysm wall shear stress (WSS), and area of elevated WSS during the cardiac cycle (time-dependent impact zone), were quantified. Unlike simulations involving aneurysms located on straight arteries, blood flow inertia (centrifugal effects) rather than viscous diffusion was the predominant force driving blood into aneurysm sacs on curved arteries. As the degree of arterial c...
293 citations
TL;DR: The use of autologous bone to reconstruct skull defects in pediatric patients after decompressive craniectomy is associated with a high incidence of bone resorption and should be reevaluated in light of the high rate of reoperation in this pediatric population.
Abstract: Object. The authors have routinely performed primary autologous cranioplasty to repair skull defects after decompressive craniectomy. The high rates of subsequent bone resorption occurring in children prompted this study. Methods. In an institutional review, the authors identified 40 (32 male and eight female) children and adolescents ranging from 4 months to 19 years of age in whom autologous cranioplasty was performed after decompressive craniectomy. The defect surface area ranged from 14 to 147 cm2. In all cases, the bone was fresh frozen at the time of the decompression. Symptomatic bone resorption subsequently occurred in 20 children (50%) in all of whom reoperation was required. The incidence of bone resorption significantly correlated with an increased skull defect area (p < 0.025). No significant correlation was found with age, sex, or anatomical location of the skull defect, number of fractured bone fragments, presence of a shunt, cause for decompressive craniectomy, method of duraplasty, or inte...
289 citations
TL;DR: Agarose gel (0.6%) is a useful surrogate for in vivo brain in exploratory studies of convection-enhanced delivery in preclinical and exploratory Studies of infusion-based intraparenchymal drug and cell delivery.
Abstract: Object. The goal of this study was to validate a simple, inexpensive, and robust model system to be used as an in vitro surrogate for in vivo brain tissues in preclinical and exploratory studies of infusion-based intraparenchymal drug and cell delivery. Methods. Agarose gels of varying concentrations and porcine brain were tested to determine the infusion characteristics of several different catheters at flow rates of 0.5 and 1 µl per minute by using bromophenol blue (BPB) dye (molecular weight [MW] ∼690) and gadodiamide (MW ∼573). Magnetic resonance (MR) imaging and videomicroscopy were used to measure the distribution of these infusates, with a simultaneous measurement of infusion pressures. In addition, the forces of catheter penetration and movement through gel and brain were measured. Agarose gel at a 0.6% concentration closely resembles in vivo brain with respect to several critical physical characteristics. The ratio of distribution volume to infusion volume of agarose was 10 compared with 7.1 for ...
285 citations
TL;DR: The hypothesis that DBS of the ventral caudate nucleus might be effective in a patient with intractable severe OCD and concomitant major depression is tested.
Abstract: Obsessive-compulsive disorder (OCD) is an anxiety disorder associated with recurrent intrusive thoughts and repetitive behaviors. Although conventional pharmacological and/or psychological treatments are well established and effective in treating OCD, symptoms remain unchanged in up to 30% of patients. Deep brain stimulation (DBS) of the anterior limb of the internal capsule has recently been proposed as a possible therapeutic alternative in treatment-resistant OCD. In the present study, the authors tested the hypothesis that DBS of the ventral caudate nucleus might be effective in a patient with intractable severe OCD and concomitant major depression. Psychiatric assessment included the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), the Hamilton Depression Rating Scale (HDRS), the Hamilton Anxiety Rating Scale (HARS), and the Global Assessment of Functioning (GAF) Scale for determining the symptom severity of OCD, depression, and anxiety as well as the quality of pychosocial and occupational functioning, respectively. Neuropsychological assessment consisted of a wide range of tests primarily exploring memory and executive functions. Deep brain stimulation of the ventral caudate nucleus markedly improved symptoms of depression and anxiety until their remission, which was achieved at 6 months after the start of stimulation (HDRS < or = 7 and HARS < or = 10). Remission of OCD (Y-BOCS < 16) was also delayed after 12 or 15 months of DBS. The level of functioning pursuant to the GAF scale progressively increased during the 15-month follow-up period. No neuropsychological deterioration was observed, indicating that DBS of the ventral caudate nucleus could be a promising strategy in the treatment of refractory cases of both OCD and major depression.
282 citations
TL;DR: Deferoxamine and other iron chelators may be potential therapeutic agents for treating ICH by reducing the oxidative stress caused by the release of iron from the hematoma.
Abstract: Object Previous studies undertaken by the authors have indicated that iron accumulation and oxidative stress in the brain contribute to secondary brain damage after intracerebral hemorrhage (ICH). In the present study the authors investigate whether deferoxamine, an iron chelator, can reduce ICH-induced brain injury. Methods Male Sprague-Dawley rats each received an infusion of 100 microl of autologous whole blood into the right basal ganglia and were killed 1, 3, or 7 days later. Iron distribution was examined histochemically (enhanced Perls reaction). The effects of deferoxamine on ICH-induced brain injury were examined by measuring brain edema and neurological deficits. Immunohistochemical analysis was performed to investigate 8-hydroxyl-2'-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, and Western blot analysis was performed to measure the amount of apurinic/apyrimidinic endonuclease/redox effector factor-1 (APE/Ref-1), a repair mechanism for DNA oxidative damage. Iron accumulation was observed in the perihematomal zone from 1 day after ICH. Deferoxamine attenuated brain edema, neurological deficits, and ICH-induced changes in 8-OHdG and APE/Ref-1. Conclusions Deferoxamine and other iron chelators may be potential therapeutic agents for ICH. They may act by reducing the oxidative stress caused by the release of iron from the hematoma.
TL;DR: Track fibers by using diffusion-tensor imaging in combination with functional localization has the potential to reduce surgical morbidity by revealing subcortical connections of the functional cortex.
Abstract: Object. The goal of this study was to use diffusion-tensor (DT) magnetic resonance (MR) imaging to track fibers combined with cortical stimulation mapping to delineate descending motor pathways. Subcortical localization of motor pathways in relation to a glioma may provide critical information to guide tumor resection and prevent surgical morbidity. Methods. Eleven adult patients harboring gliomas underwent MR imaging 1 day prior to image-guided intraoperative cortical motor mapping and tumor resection. Screens depicting 27 cortical motor sites on a surgical navigation system were saved to launch DT imaging of fiber tracks of descending motor pathways. The position and organization of motor tracts were visualized by fiber tracking. Tracks from 16 motor stimulation sites followed descending pathways from the precentral gyrus, through the corona radiata and internal capsule, and into the cerebral peduncle. These tracks were also observed on DT images to diverge along crossing white matter bundles (four patients) and to terminate or deviate in regions of peritumoral vasogenic edema (five patients). Conclusions. The use of precise intraoperative cortical mapping information and DT images of fiber tracks can reveal the course of motor pathways beneath the cortex. The subcortical fiber tracks generated are consistent with the known anatomical course and somatotopic organization of the motor tract in relation to its cortical origins. Tracking fibers by using DT imaging in combination with functional localization has the potential to reduce surgical morbidity by revealing subcortical connections of the functional cortex.
TL;DR: The hypothesis that normobaric hyperoxia in patients with severe TBI improves the indices of brain oxidative metabolism is supported.
Abstract: Object. The effect of normobaric hyperoxia (fraction of inspired O2 [FIO2] concentration 100%) in the treatment of patients with traumatic brain injury (TBI) remains controversial. The aim of this study was to investigate the effects of normobaric hyperoxia on five cerebral metabolic indices, which have putative prognostic significance following TBI in humans. Methods. At two independent neurointensive care units, the authors performed a prospective study of 52 patients with severe TBI who were treated for 24 hours with 100% FIO2, starting within 6 hours of admission. Data for these patients were compared with data for a cohort of 112 patients who were treated in the past; patients in the historical control group matched the patients in our study according to their Glasgow Coma Scale scores after resuscitation and their intracranial pressure within the first 8 hours after admission. Patients were monitored with the aid of intracerebral microdialysis and tissue O2 probes. Normobaric hyperoxia treatment resulted in a significant improvement in biochemical markers in the brain compared with the baseline measures for patients treated in our study (patients acting as their own controls) and also compared with findings from the historical control group. In the dialysate the glucose levels increased (369.02 620.1 mmol/L in the control group and 466.9 6 20.39 mmol/L in the 100% O2 group, p = 0.001), whereas the glutamate and lactate levels significantly decreased (p , 0.005). There were also reductions in the lactate/glucose and lactate/pyruvate ratios. Intracranial pressure in the treatment group was reduced significantly both during and after hyperoxia treatment compared with the control groups (15.03 6 0.8 mm Hg in the control group and 12.13 6 0.75 mm Hg in the 100% O2 group, p , 0.005) with no changes in cerebral perfusion pressure. Outcomes of the patients in the treatment group improved. Conclusions. The results of the study support the hypothesis that normobaric hyperoxia in patients with severe TBI improves the indices of brain oxidative metabolism. Based on these data further mechanistic studies and a prospective randomized controlled trial are warranted.
TL;DR: High levels of inflammatory cytokines were significantly correlated with recurrence and layering CSDH; a prolonged postoperative antiinflammatory medicine given as prophylaxis may help prevent the recurrence of a CSDH.
Abstract: Object. To evaluate the role of local inflammation in the pathogenesis and postoperative recurrence of chronic subdural hematoma (CSDH), the authors conducted an investigation in a selected group of patients who could clearly recall a traumatic event and who did not have other risk factors for CSDH. Inflammation was analyzed by measuring the concentration of the proinflammatory and inflammatory cytokines interleukin (IL)-6 and IL-8. The authors also investigated the possible relationship between high levels of local inflammation that were measured and recurrence of the CSDH. Methods. A prospective study was performed between 1999 and 2001. Thirty-five patients who could clearly recall a traumatic event that had occurred at least 3 weeks previously and who did not have risk factors for CSDH were enrolled. All patients were surgically treated by burr hole irrigation plus external drainage. The concentration of inflammatory cytokines was very high in the lesion, whereas it was normal in serum. In five cases ...
TL;DR: Shunting of CSF through a lumbar drain after an SAH markedly reduces the risk of clinically evident vasospasm and its sequelae, shortens hospital stay, and improves outcome.
Abstract: Object Cerebral vasospasm after subarachnoid hemorrhage (SAH) continues to be a major source of morbidity in patients despite significant clinical and basic science research. Efforts to prevent vasospasm by removing spasmogens from the subarachnoid space have produced mixed results. The authors hypothesize that lumbar cisternal drainage can remove blood from the basal subarachnoid spaces more effectively than an external ventricular drain (EVD). This nonrandomized, controlled-cohort study was undertaken to evaluate the effectiveness of a lumbar drain in patients with SAH compared with those in whom an EVD or no form of cerebrospinal fluid (CSF) drainage was used to prevent the development of clinical vasospasm and its sequelae. Methods The authors collected data on 266 patients with nontraumatic SAH who were admitted to the University of Utah Health Sciences Center between January 1994 and January 2003. Of these, 167 met the study entry criteria. The treatment group consisted of 81 patients in whom a lumb...
TL;DR: CSF shunts were extremely effective in the acute treatment of pseudotumor cerebri-associated intractable headache, providing long-term relief in the majority of patients.
Abstract: Object. Cerebrospinal fluid (CSF) shunts effectively reverse symptoms of pseudotumor cerebri postoperatively, but long-term outcome has not been investigated. Lumboperitoneal (LP) shunts are the mainstay of CSF shunts for pseudotumor cerebri; however, image-guided stereotaxy and neuroendoscopy now allow effective placement of a ventricular catheter without causing ventriculomegaly in these cases. To date it remains unknown if CSF shunts provide long-term relief from pseudotumor cerebri and whether a ventricular shunt is better than an LP shunt. The authors investigated these possibilities. Methods. The authors reviewed the records of all shunt placement procedures that were performed for intractable headache due to pseudotumor cerebri at one institution between 1973 and 2003. Using proportional hazards regression analysis, predictors of treatment failure (continued headache despite a properly functioning shunt) were assessed, and shunt revision and complication rates were compared between LP and ventricul...
TL;DR: This cooling helmet delivers initial rapid and selective brain cooling and maintains a significant temperature gradient between the core and brain temperatures throughout the hypothermic period to provide sufficient regional hypothermia yet minimize systemic complications.
Abstract: Object Hypothermia is by far the most potent neuroprotectant. Nevertheless, timely and safe delivery of hypothermia remains a clinical challenge. To maximize neuroprotection yet minimize systemic complications, ultra-early delivery of selective cerebral hypothermia by Emergency Medical Service (EMS) personnel in the field would be advantageous. The authors (W.E. and H.W.) have developed a cooling helmet by using National Aeronautics and Space Administration spinoff technology. In this study its effectiveness in lowering brain temperature in patients with severe stroke or head injury is examined. Methods Patients were randomly assigned to groups receiving either the cooling helmet or no cooling, and brain temperatures (0.8 cm below the cortical surface) were continuously monitored for a mean of 48 to 72 hours with a Neurotrend sensor and then compared with the patients' core temperatures. There were eight patients in the study group and six in the control group. The mean change in temperature (brain — body...
TL;DR: Although the availability of MEG is still limited across epilepsy surgery centers, this study method may be substituted for the Wada procedure in assessing hemispheric dominance for language in select cases.
Abstract: Object. In this study the authors evaluated the sensitivity and selectivity of a noninvasive language mapping procedure based on magnetoencephalography (MEG), for determining hemispheric dominance for language functions. Methods. Magnetic activation profiles of the brain were obtained from 100 surgical candidates (age range 8‐56 years) with medically intractable seizure disorder by using a whole-head MEG system within the context of a word recognition task. The degree of language-specific activity was indexed according to the number of consecutive sources (modeled as single, moving current dipoles) in perisylvian brain areas. Only activity sources that were observed with a high degree of spatial and temporal overlap in two split-half data sets were used to compute the MEG laterality index. Independently, all patients underwent Wada testing for the determination of hemispheric dominance for language. Independent clinical judgments based on MEG and Wada data showed a high degree of concordance (87%). Magnetoencephalography laterality judgments had an overall sensitivity of 98%, but a lower selectivity of 83%, which was due to the fact that MEG detected more activity in the nondominant hemisphere than was predicted based on the Wada test. A number of objective criteria were derived based on this large patient series to ensure data quality and bolster the clinical usefulness of MEG for language mapping. Conclusions. Although the availability of MEG is still limited across epilepsy surgery centers, this study method may be substituted for the Wada procedure in assessing hemispheric dominance for language in select cases.
TL;DR: The single-stage posterolateral transpedicular approach to decompress the spine circumferentially and to place instrumentation achieved a high success rate for pain palliation, neurological preservation, and functional improvement, while avoiding the morbidity associated with combined approaches.
Abstract: Object. Patients with metastatic spine tumors often have multicolumn involvement and high-grade epidural compression, requiring circumferential decompression and instrumentation. Secondary medical and oncological issues add morbidity to combined approaches. The authors present their experience in using the single-stage posterolateral transpedicular approach (PTA) to decompress the spine circumferentially and to place instrumentation. Methods. From September 1997 to February 2004, 140 patients with spine metastases underwent the PTA. Magnetic resonance imaging revealed high-grade spinal cord compression in 120 patients (86%) and lytic vertebral body destruction in all patients. Preoperatively 84 patients (60%) received radiotherapy directed to the involved level and 42 (30%) underwent tumor embolization. Following circumferential decompression, all patients underwent anterior reconstruction with polymethylmethacrylate and Steinmann pins, and posterior segmental fixation. The median operative time was 5.1 h...
TL;DR: Elevated ICP post-SAH is associated with a worse patient outcome, particularly if ICP does not respond to treatment, however, this association may depend more on the overall severity of the SAH than on ICP alone.
Abstract: 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...
TL;DR: It is necessary to map both languages in bilinguals because L1 and L2 sites are functionally distinct, and language organization comparisons in bilingual and monolingual brains demonstrate the presence of L2-restricted zones, which are dedicated to L1.
Abstract: Object. The aim of this investigation was to address three questions in bilingualism research: 1) are multiple languages functionally separated within the bilingual brain; 2) are these languages similarly organized; and 3) does language organization in bilinguals mirror that in monolinguals? Methods. During awake dominant-hemisphere craniotomy in each of 25 bilingual patients, the authors mapped both languages by using identical object-naming stimuli. Essential sites for primary (L1) and secondary (L2) languages were compared. Sites were photographically recorded and plotted onto an anatomically referenced grid system. Language organization in bilinguals was then compared with that in 117 monolinguals and 11 monolingual children. Conclusions. The authors found distinct language-specific sites as well as shared sites that support both languages. The L1 and L2 representations were similar in total cortical extent but significantly different in anatomical distribution. The L2-specific sites were located excl...
TL;DR: Monitoring of MEPs is superior to SSEP monitoring and MDU in detecting motor impairment, particularly that from subcortical ischemia in aneurysm surgery, but microvascular Doppler ultrasonography is superior in detecting inadvertent vessel occlusion, but cannot assess remote collateral flow.
Abstract: Object. The aims of this study were to compare the efficiency of motor evoked potentials (MEPs), somatosensory evoked potentials (SSEPs), and microvascular Doppler ultrasonography (MDU) in the detection of impending motor impairment from subcortical ischemia in aneurysm surgery; to determine their sensitivity for specific intraoperative events; and to compare their impact on the surgical strategy used. Methods. Motor evoked potentials, SSEPs, and MDU were monitored during 100 operations for 129 aneurysms in 95 patients. Intraoperative events, monitoring results, and clinical outcome were correlated in a prospective observational design. Motor evoked potentials indicated inadequate temporary clipping, inadvertent occlusion, inadequate retraction, vasospasm, or compromise to perforating vessels in 21 of 33 instances and deteriorated despite stable SSEPs in 18 cases. Microvascular Doppler ultrasonography revealed inadvertent vessel occlusion in eight of 10 cases and insufficient clipping in four of four case...
TL;DR: The most constant insular area of supply was from the prefrontal and precentral arteries that supplied the anterior and middle short gyri, respectively, and the precentral insular vein was the one that most commonly connected to the superficial sylvian vein.
Abstract: Object. The purpose of this study was to define the topographic anatomy, arterial supply, and venous drainage of the insula and sylvian fissure. Methods. The neural, arterial, and venous anatomy of the insula and sylvian fissure were examined in 43 cerebral hemispheres. Conclusions. The majority of gyri and sulci of the frontoparietal and temporal opercula had a constant relationship to the insular gyri and sulci and provided landmarks for approaching different parts of the insula. The most lateral lenticulostriate artery, an important landmark in insular surgery, arose 14.6 mm from the apex of the insula and penetrated the anterior perforated substance 15.3 mm medial to the limen insulae. The superior trunk of the middle cerebral artery (MCA) and its branches supplied the anterior, middle, and posterior short gyri; the anterior limiting sulcus; the short sulci; and the insular apex. The inferior trunk supplied the posterior long gyrus, inferior limiting sulcus, and limen area in most hemispheres. Both of these trunks frequently contributed to the supply of the central insular sulcus and the anterior long gyrus. The areas of insular supply of the superior and inferior trunks did not overlap. The most constant insular area of supply by the cortical MCA branches was from the prefrontal and precentral arteries that supplied the anterior and middle short gyri, respectively. The largest insular perforating arteries usually arose from the central and angular arteries and most commonly entered the posterior half of the central insular sulcus and posterior long gyrus. Insular veins drained predominantly to the deep middle cerebral vein, although frequent connections to the superficial venous system were found. Of all the insular veins, the precentral insular vein was the one that most commonly connected to the superficial sylvian vein.
TL;DR: Tumors that present with complex genetic alterations, even those with a benign histological grade, are potentially aggressive and require closer follow up and the FISH method appears to be more accurate than the standard cytogenetic one in detecting these alterations.
Abstract: Object. The malignant progression of benign tumors is well documented in gliomas and other systemic lesions. It is also well known that some meningiomas become progressively aggressive despite their original benign status. The theory of clonal evolution is widely believed to explain malignant progression in meningioma; however, the data used to explain stepwise progression have typically been derived from the cytogenetic analysis of different types of tumors of different grades and in different patients. In this study, the authors examined the data obtained in a group of patients with meningiomas that showed clear histopathological progression toward a higher grade of malignancy and then analyzed the underlying cytogenetic findings. Methods. Among 175 patients with recurrent meningiomas, 11 tumors showed a histopathological progression toward a higher grade that was associated with an aggressive clinical course. Six tumors progressed to malignancy and five to the atypical category over a period averaging ...
TL;DR: The artificial graft made with BMSC-DSCs represents an alternative method for the difficult reconstruction of a long distance gap in a peripheral nerve.
Abstract: Object. Bone marrow stromal cells (BMSCs) can be induced to form Schwann cells by sequentially treating the cells with β-mercaptoethanol and retinoic acid, followed by forskolin and neurotrophic factors including heregulin. In this study the authors made artificial grafts filled with BMSC-derived Schwann cells (BMSC-DSCs) and transplanted them into the transected sciatic nerve in adult rats to evaluate the potential of BMSCs as a novel alternative method of peripheral nerve regeneration. Methods. The BMSC-DSCs were suspended in Matrigel and transferred into hollow fibers (12 mm in length), which were transplanted into the transected sciatic nerve in adult Wistar rats. Six months after cell transplantation, electrophysiological evaluation and walking track analysis were performed. Results of these studies showed significant improvement in motor nerve conduction velocity and sciatic nerve functional index in the BMSC-DSC—transplanted group compared with the control group (Matrigel graft only). Immunohistoch...
TL;DR: In the present study, ETV failed in eight patients and the time to failure after the procedure was a mean of 3.4 months, and the authors found that the aqueductal stenosis subgroup had the highest proportion of functioning ETV (89%).
Abstract: Object. The purpose of this paper is to elucidate the safety and efficacy of, and indications and outcome prognosis for endoscopic third ventriculostomy (ETV) in 58 patients with obstructive hydrocephalus. Methods. Between September 1999 and April 2003, 58 ETVs were performed in 58 patients with obstructive hydrocephalus (36 male and 22 female patients) at the authors' institution. The ages of the patients ranged from 5 to 67 years (mean age 35 years) and the follow-up period ranged from 3 to 41 months (mean duration of follow up 24 months). Patients were divided into four subgroups based on the cause of the obstructive hydrocephalus: 21 with intracranial tumors; 11 with intracranial cysts; 18 with aqueductal stenosis; and eight with intracranial hemorrhage or infection. Both univariate and multi-variate statistical analyses were performed to assess the prognostic relevance of the cause of the obstructive hydrocephalus, early postoperative clinical appearance, and neuroimaging findings in predicting the r...
TL;DR: R Rathke cleft cysts are associated with a variety of clinical presentations and sometimes confusing intraoperative and pathological findings, especially after a partial removal, as in cases with squamous metaplasia.
Abstract: Object. Rathke cleft cysts (RCCs) are rarely symptomatic. The purpose of this study was to clarify the clinical, neuroimaging, surgical, and pathological features of symptomatic RCCs with special attention to their recurrence. Methods. This retrospective study involved 53 patients with pathologically confirmed symptomatic RCCs. There were 28 female and 25 male patients, ranging in age from 11 to 68 years (mean 37 years). Common clinical presentations included headache, visual impairment, and endocrine disturbance. The most common endocrine disturbances were hyperprolactinemia and diabetes insipidus. Most of these improved or were resolved after surgery, with the exception of diabetes insipidus and panhypopituitarism. The cysts were intrasellar with suprasellar extension in 33 patients, and ranged in size from 5 to 40 mm (mean 17 mm). In the 50 magnetic resonance (MR) images that were reviewed, the signal intensities were quite variable. Fourteen MR images demonstrated enhancement after an injection of Gd. Intraoperatively, the cyst contents were found to be yellowish (18 patients [37%]) and mucoid (25 patients [51%]). Pathological examinations revealed a pseudostratified columnar epithelium in 26 patients (49%). Abundant squamous metaplasia and a stratified squamous epithelium were also found in 12 patients (23%). Follow-up MR images revealed cyst recurrences that required a repeated operation in six patients. Statistically significant risk factors for a recurrence included enhancement of the lesion on MR images (p = 0.017), the extent of cyst removal (p = 0.012), and the presence of squamous epithelium (p = 0.008). Conclusions. Rathke cleft cysts are associated with a variety of clinical presentations and sometimes confusing intraoperative and pathological findings. Close postoperative observation with neuroimaging and neuroophthalmological assessment is necessary, especially after a partial removal, as in cases with squamous metaplasia.
TL;DR: A retrospective review of clinical notes and radiological studies found patterns of failure following radiosurgery with regard to the pain and tumor control in patients with solitary spinal metastases can achieve rapid and durable pain control.
Abstract: Object. Single-dose radiosurgery for solitary spinal metastases can achieve rapid and durable pain control. This study was conducted to determine the patterns of failure after spinal radiosurgery. Methods. Forty-nine patients with 61 solitary spinal metastases underwent radiosurgery between May 2001 and May 2003. Single-dose radiosurgery (10–16 Gy) was delivered only to the involved spinal segments. The authors undertook a retrospective review of clinical notes, including patient questionnaires and radiological studies (computerized tomography or magnetic resonance imaging), to analyze patterns of failure following radiosurgery with regard to the pain and tumor control. Complete and partial pain relief was achieved in 85% of the lesions treated. Relapse of pain at the treated site was noted in 7%. Radiologically, lesions progressively metastasized to the immediately adjacent spines in 5%. These patients also had progressive primary and/or other systemic metastatic diseases. Conclusions. Spine-related pain...
TL;DR: The size and position of the subthalamic nucleus is appearing to be smaller and situated more posterior and lateral on MR images than in atlases, and care must be taken in relying on coordinates relative to the commissures for targeting of the STN.
Abstract: Object. The subthalamic nucleus (STN) is a target in surgery for Parkinson disease, but its location according to brain atlases compared with its position on an individual patient's magnetic resonance (MR) images is incompletely understood. In this study both the size and location of the STN based on MR images were compared with those on the Talairach and Tournoux, and Schaltenbrand and Wahren atlases. Methods. The position of the STN relative to the midcommissural point was evaluated on 18 T2-weighted MR images (2-mm slices). Of 35 evaluable STNs, the most anterior, posterior, medial, and lateral borders were determined from axial images, dorsal and ventral borders from coronal images. These methods were validated using histological measurements in one case in which a postmortem examination was performed. The mean length of the anterior commissure—posterior commissure was 25.8 mm. Subthalamic nucleus borders derived from MR imaging were highly variable: anterior, 4.1 to −3.7 mm relative to the midcommiss...
TL;DR: Results of similar models indicated that among patients with intraventricular hemorrhage (IVH), surgical clip application carried a lower risk of shunt-dependent hydrocephalus compared with that for endovascular embolization.
Abstract: Object. This study was designed to determine whether the frequency of shunt-dependent hydrocephalus in patients suffering from aneurysmal subarachnoid hemorrhage (SAH) differs when comparing surgical clip application with endovascular obliteration of ruptured aneurysms. Methods. In this prospective nonrandomized study, 245 patients with aneurysmal SAH treated using either surgical clip application or endovascular coil embolization were studied at our institution between September 1997 and March 2003. One hundred eighty patients underwent clip application and 65 had coil embolization. In those patients who underwent clip application of anterior circulation aneurysms, the lamina terminalis was systematically fenestrated. The occurrence of acute, asymptomatic, and shunt-dependent hydrocephalus was analyzed in both treatment groups. A subgroup analysis of patients with good clinical grade (World Federation of Neurosurgical Societies [WFNS] Grades I–III) and better Fisher Grade (1–3) and of patients with Fishe...