bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relationship of Local Infarctions to Cognitive and Psychosocial Impairments after Aneurysmal Subarachnoid Hemorrhage
Authors: Vilkki Juhani S. , Juvela Seppo , Siironen Jari , Ilvonen Titta , Varis Joona , Porras Matti 
Published: October 2004

Abstract

OBJECTIVE:
Previous studies suggest that cognitive and psychosocial impairments after subarachnoid hemorrhage (SAH) result from diffuse brain damage caused by the initial bleeding rather than from focal lesions. We describe the relationship of local infarctions to these impairments and explore how well test and questionnaire results explain psychosocial outcome.

METHODS:
A total of 170 patients, selected from a consecutive series of patients with aneurysmal SAH, underwent neurological and neuroradiological examinations, and 138 of them were assessed with neuropsychological tests and questionnaires 1 year after SAH.

RESULTS:
Patients with left and bilateral infarctions performed worse on verbal memory tests than the other patients, and patients with left infarctions had more impaired working capacity than those with no infarction. The indices of the severity of SAH were related to reductions in both working capacity and social activity but less clearly to poor test performances. Whereas the modified Rankin scale was the most important correlate of working capacity, performance on cognitive tests was associated with return to work, and questionnaire ratings of mental impairments correlated with reduced working capacity and decreased social activity.

CONCLUSION:
Left-hemisphere infarctions cause deficits in verbal memory and working capacity. The severity of SAH is associated with impairments in working capacity and social activity rather than with specific cognitive deficits. Patients' and partners' opinions on patients' mental impairments could provide complementary information to clinical grades and cognitive tests in the evaluation of outcome after SAH.
Spinal Dural Arteriovenous Fistulae: Analysis of Outcome in Relation to Pretreatment Indicators
Authors: Cenzato Marco , Versari Pietro , Righi Claudio , Simionato Franco , Casali Cecilia , Giovanelli Massimo 
Published: October 2004

Abstract

OBJECTIVE:
The outcome of treatment for a spinal dural arteriovenous fistula is unpredictable. In this study, we reviewed the outcome of patients treated for this condition, in relation to pretreatment indicators.

METHODS:
We reviewed the records of 37 consecutive patients treated either surgically or endovascularly in our department between 1989 and 2002.

RESULTS:
At follow-up, 78% of the patients reported improvement. Those with motor symptoms had the best outcome: improvement was achieved in more than 60% of the patients, amounting to 1 or 2 points on the Aminoff scale. Sensory disorders improved in 43% of cases, pain in 61%, and sphincter impairment in only 37%. Patients with a fistula in the lower thoracic region did better than those with fistulae in other locations.

CONCLUSION:
The clinical state before treatment is certainly relevant in predicting outcome. Age and duration of the symptoms before treatment have no direct relation to the chances of improvement with treatment, particularly when motor improvement is considered. The modality of onset of symptoms and location of the fistula play significant roles, also: a fistula in the lower thoracic segment was associated with more severe symptoms but tended to improve more (83%, P = 0.04) after treatment. Midthoracic and lumbar fistulae showed a lower incidence of improvement (&lt;50%).
Relationship between Valve Opening Pressure, Body Position, and Intracranial Pressure in Normal Pressure Hydrocephalus: Paradigm for Selection of Programmable Valve Pressure Setting
Authors: Bergsneider Marvin , Yang Isaac , Hu Xiao , McArthur David L. , Cook Shon W. , Boscardin W J. 
Published: October 2004

Abstract

OBJECTIVE:
There is little scientific basis for guidance in selecting the optimal valve for the treatment of normal pressure hydrocephalus. The aim of this study was to determine the programmable valve opening pressure setting that would result in a slight reduction in intracranial pressure (ICP) after a ventriculoperitoneal shunt is implanted. We also assessed whether shunt-induced ICP could be predicted on the basis of a simple hydrodynamic equation.

METHODS:
In this prospective study of 11 patients with normal pressure hydrocephalus, ICP was measured before and after implantation of a shunt incorporating a programmable valve without an antisiphon device. Pressure measurements, including intraperitoneal pressure, were recorded at body angles ranging from 0 to 55 degrees and at valve settings ranging from 30 to 200 mm H2O. Measured ICP values were compared with values computed using a simple hydrodynamic equation.

RESULTS:
Even at a valve setting greater than the mean baseline ICP (200 mm H2O), the supine ICP was significantly lower than the baseline value (baseline ICP, 164 ± 64 mm H2O; postoperative ICP, 125 ± 69 mm H2O, P = 0.04). Valve pressure did not equate 1:1 with the measured postoperative ICP. Comprehensive ICP measurements at upright body positions demonstrated a stepwise reduction in ICP rather than a precipitous decline as a result of so-called siphoning.

CONCLUSION:
This study indicates that very high valve opening pressure settings may be optimal for the initial treatment of normal pressure hydrocephalus. The relationship between ICP and opening pressure valves is linear but not predicted by simple hydrodynamics.
Treatment of Unruptured Cerebral Aneurysms by Embolization with Guglielmi Detachable Coils: Case-fatality, Morbidity, and Effectiveness in Preventing Bleeding—A Systematic Review of the Literature
Authors: Lanterna Luigi A. , Tredici Giovanni , Dimitrov Borislav D. , Biroli Francesco 
Published: October 2004

Abstract

OBJECTIVE:
Guglielmi detachable coils (GDCs) increasingly are being used to treat unruptured cerebral aneurysms (UCAs). We systematically reviewed the literature to assess the case-fatality and permanent morbidity rates of GDC embolization of UCAs and the postembolization bleeding rate.

METHODS:
Through a MEDLINE search of the English, Italian, and French literature from January 1990 through December 2002, we retrieved studies on GDC embolization of aneurysms and extracted data on UCAs. Inclusion criteria were: 1) attempted GDC embolization of at least five consecutive patients with UCAs, 2) reported percentage of at least either case-fatality or permanent morbidity rate or crude data allowing an independent calculation. When data on UCAs could not be characterized with certainty among data on other, different lesions, the study was rejected.

RESULTS:
We included 30 studies. One thousand three hundred seventy-nine patients were available for the calculation of the case-fatality rate, 794 for the permanent morbidity rate, and 703 for the bleeding rate. The case-fatality rate was 0.6% (95% confidence interval, 0.2–1%), the permanent morbidity rate was 7% (95% confidence interval, 5.3–8.7%), and the bleeding rate was 0.9% per year (95% confidence interval, 0.41–1.4%). Only incompletely coiled UCAs of 10 mm or more accounted for the bleeding events. Morbidity decreased from 8.6% to 4.5% (P &lt; 0.05) when the midyear of study (average calendar year of treatment) was 1995 or later.

CONCLUSION:
GDC embolization of UCAs is relatively safe, and the outcome is progressively improving. Partial embolization of UCAs of 10 mm or more is unlikely to provide an acceptable protection. Most of the source publications suffer from methodological weaknesses. Prospective studies with longer follow-up periods are needed to definitively assess the effectiveness of GDCs on UCAs.
Functional Magnetic Resonance Imaging and Optical Imaging for Dominant-hemisphere Perisylvian Arteriovenous Malformations
Authors: Cannestra Andrew F. , Pouratian Nader , Forage James , Bookheimer Susan Y. , Martin Neil A. , Toga Arthur W. 
Published: October 2004

Abstract

OBJECTIVE:
In this study, we developed an a priori system to stratify surgical intervention of perisylvian arteriovenous malformations (AVMs) in 20 patients. We stratified the patients into three categories based on preoperative functional magnetic resonance imaging (fMRI) language activation pattern and relative location of the AVM.

METHODS:
In Group I (minimal risk), the AVM was at least one gyrus removed from language activation, and patients subsequently underwent asleep resection. In Group II (high risk), the AVM and language activation were intimately associated. Because the risk of postoperative language deficit was high, these patients were then referred to radiosurgery. In Group III (indeterminate risk), the AVM and language were adjacent to each other. The risk of language deficit could not be predicted on the basis of the fMRI alone. These patients underwent awake craniotomy with electrocortical stimulation mapping and optical imaging of intrinsic signals for language mapping.

RESULTS:
All patients from Group I (minimal risk) underwent asleep resection without deficit. All Group II (high-risk) patients tolerated radiosurgery without complication. In Group III (indeterminate risk), three patients underwent successful resection, whereas two underwent aborted resection after intracranial mapping.

CONCLUSION:
We advocate the use of fMRI to assist in the preoperative determination of operability by asleep versus awake craniotomy versus radiosurgery referral. In addition, we advocate the use of all three functional mapping (fMRI, electrocortical stimulation mapping, and optical imaging of intrinsic signals) techniques to clarify the eloquence score of the Spetzler-Martin system before definitive treatment (anesthetized resection versus radiosurgery versus intraoperative resection versus intraoperative closure and radiosurgery referral).
Taurine Detection by Proton Magnetic Resonance Spectroscopy in Medulloblastoma: Contribution to Noninvasive Differential Diagnosis with Cerebellar Astrocytoma
Authors: Moreno-Torres Ángel , Martínez-Pérez Irene , Baquero Miguel , Campistol Jaume , Capdevila Antoni , Arús Carles , Pujol Jesus 
Published: October 2004

Abstract

OBJECTIVE:
We sought to evaluate whether taurine detection in short-echo (20 ms) proton magnetic resonance spectroscopy contributes to the noninvasive differential diagnosis between medulloblastoma and cerebellar astrocytoma in children and young adults. These two types of tumor have very different prognoses and may be difficult to differentiate by neuroradiological or clinical means.

METHODS:
Single-voxel proton magnetic resonance spectra of tumors were acquired at 1.5 T in 14 patients with biopsy-proven primary cerebellar tumors (six medulloblastomas, seven astrocytomas, and one mixed astroependymoma) using short-echo time (20 ms) and long-echo time (135 ms). For taurine assignment, qualitative analysis was performed on short-echo time spectra and results were compared in vitro with spectra of model solutions. Perchloric acid extracts of postsurgical tumor biopsies were performed in two medulloblastoma cases.

RESULTS:
Taurine detection was demonstrated in all patients with medulloblastoma and in none of those with astrocytoma. We were unable to ascertain any relationship between taurine and metastatic spread within the medulloblastoma group.

CONCLUSION:
Medulloblastomas characteristically seem to show taurine detectable in vivo by short-echo proton magnetic resonance spectroscopy, which may help to discriminate medulloblastoma from cerebellar astrocytoma.
Operative Findings and Outcomes of Microvascular Decompression for Trigeminal Neuralgia in 35 Patients Affected by Multiple Sclerosis
Authors: Broggi Giovanni , Ferroli Paolo , Franzini Angelo , Nazzi Vittoria , Farina Laura , La Mantia Loredana , Milanese Clara 
Published: October 2004

Abstract

OBJECTIVE:
The concept of vascular compression of the trigeminal root as the main etiological factor in idiopathic trigeminal neuralgia has achieved widespread acceptance, and microvascular decompression (MVD) is a well-established surgical procedure for its treatment. Multiple sclerosis (MS) has long been considered to be an absolute contraindication to MVD because of the supposed exclusive causative role of a demyelinating lesion affecting the trigeminal root entry zone. Magnetic resonance imaging preoperative identification of suspicious vessels along the cisternal course of the trigeminal nerve in MS patients raises the question of a possible causative role of vascular compression in MS patients.

METHODS:
We describe magnetic resonance imaging findings, surgical findings, and outcomes in 35 MS patients who underwent MVD for medically intractable trigeminal neuralgia. Results were assessed by clinical follow-up and periodic phone surveys. The mean follow-up was 44 months (range, 6–108 mo).

RESULTS:
Magnetic resonance imaging revealed the presence of demyelinating lesions affecting the brainstem trigeminal pathways of the painful side in 26 (74%) of 35 patients. During surgery, severe neurovascular compression at the trigeminal root entry zone was found in 16 (46%) of 35 patients. The long-term outcome was excellent in 39%, good in 14%, fair in 8%, and poor in 39% of patients. No statistically significant prognostic factor predicting good outcome could be found. There was no mortality, with a 2.5% long-term morbidity rate (facial nerve palsy in one patient).

CONCLUSION:
Results of MVD in trigeminal neuralgia MS patients are much less satisfactory than in the idiopathic group, indicating that central mechanisms play a major role in pain genesis.
Microvascular Decompression for Trigeminal Neuralgia in the Elderly: A Review of the Safety and Efficacy
Authors: Ashkan Keyoumars , Marsh Henry 
Published: October 2004

Abstract

OBJECTIVE:
To critically examine the efficacy and safety of microvascular decompression (MVD) for trigeminal neuralgia (TN) in elderly patients.

METHODS:
We performed a retrospective review of medical records, followed by prospective follow-up. The outcome data from 44 MVD operations for TN performed in 40 consecutive patients with a mean age of 65 years (range, 60–75 yr) in the period 1991 to 2001 were compared with those from 40 younger control subjects (mean age, 46 yr; range, 20–59 yr) operated on during the same period.

RESULTS:
The median time from diagnosis of TN to MVD in the older patients was 7 years (range, 1–22 yr), compared with 3 years (range, 3 mo to 20 yr) in the younger group (P = 0.02). With the exception of one, all patients in this study were classified as American Society of Anesthesiologist Grade 1 or 2. Initial pain relief was achieved in 98 and 100% of the patients in the study and control groups, respectively. There were no operative mortalities or life-threatening morbidities. Transient facial numbness and diplopia occurred in both groups. Headaches, nausea, and vomiting were more frequent in the younger patients, whereas wound infection and confusion were more common in the older patients. The mean length of hospital stay was 5.4 days (range, 3–10 d) for the older patients, compared with 5.3 days (range, 3–9 d) for the control group (P = 0.4). After average follow-ups of 30 and 33 months, the pain recurred in 24 and 27% of the patients in the elderly and control groups, respectively.

CONCLUSION:
MVD is underused in the elderly despite being both safe and effective. Fitness and not age should be the key in deciding the treatment options. It is proposed that any patient with medically refractory TN who is fit for general anesthesia should be given the opportunity to choose MVD.
Gilliatt-Sumner Hand Revisited: A 25-year Experience
Authors: Tender Gabriel C. , Thomas Ajith J. , Thomas Najeeb , Kline David G. 
Published: October 2004

Abstract

OBJECTIVE:
Thirty-three patients with true neurogenic thoracic outlet syndrome, or Gilliatt-Sumner hand, underwent surgical treatment at Louisiana State University during a 25-year period. This study retrospectively evaluated the outcome referable to pain and motor function in these patients.

METHODS:
All patients had the typical Gilliatt-Sumner hand, secondary to compression of C8, T1, and/or lower trunk. Nineteen patients underwent an anterior supraclavicular approach, and 15 patients underwent a posterior subscapular approach to the brachial plexus. Nerve action potential recordings showed plexus involvement close to the spine, at the level of the junction of the spinal nerves to the lower trunk.

RESULTS:
Pain, present in 22 patients, improved in 21. Mild motor deficit improved in 12 of 14 patients. Severe motor deficit improved partially in 14 of 20 patients.

CONCLUSION:
The diagnosis of true neurogenic thoracic outlet syndrome provides a clear operative indication. Surgical decompression needs to involve the medial portion of the plexus, and especially the spinal nerves. An anterior supraclavicular approach is preferred in most cases. If there is a large cervical rib or there has been a prior anterior operation, then a posterior subscapular approach is indicated.
Development of Hybrid Integrated Endoscope-holder System for Endoscopic Microneurosurgery
Authors: Morita Akio , Okada Yoshikazu , Kitano Masahiko , Hori Tomokatsu , Taneda Mamoru , Kirino Takaaki 
Published: October 2004

Abstract

OBJECTIVE:
Endoscopic techniques in the field of neurosurgery are under development. To perform sophisticated bimanual procedures in the delicate surgical fields of neurosurgery, rigid endoscope fixation devices with accurate locking and a safe releasing system are required. Here, we report the development of a new hybrid integrated endoscope-holder system.

INSTRUMENTATION:
The basic concepts of the holding device were as follows: 1) it should combine both video system and holding device; 2) it should have easy maneuverability and accurate fixation and be equipped with a safe releasing mechanism; and 3) it should be able to be used universally either in a primary or an assisting endoscopic procedure. A negatively actuated air-locking system and a bayonet-shaped endoscope were newly developed. Clinical trials of 25 patients were performed, and each prototype was tested and modified until the functional requirements were fulfilled. The final version was tested for accuracy and security in fixation and releasing mechanism.

RESULTS:
Eight problems were encountered in the clinical trials and improved. Accuracy in fixation of the final version was superior to the most advanced endoscope-holder on the market. No dangerous events were observed during repetitive insertion, fixation, and release in the simulated deep surgical field in the cadaveric skull. No apparent complications were noted in the clinical application.

CONCLUSION:
We have developed a highly reliable, accurately fixable, and easily maneuverable hybrid endoscope-holder system. To achieve a safer, more accurate, and less invasive surgery in the current socioeconomic demands, commercial manufacturers and surgeons in multiple centers need to combine their efforts to create useful techniques.
Multi-Stage Amphoteric Redox Hydrocarbons Based on a Phenalenyl Radical
Authors: Nakasuji Kazuhiro , Kubo Takashi 
Published: October 2004

Abstract
Molecular design and properties of amphoteric redox hydrocarbons are reviewed. Our molecular design is based on a phenalenyl radical, which has a non-bonding molecular orbital with an occupation number of one and is known to behave as a two-stage amphoteric redox system. We have prepared eight amphoteric redox compounds containing two or three phenalenyl units. Cyclic voltammetry showing small E1sum values confirms the high amphotericity of these compounds. The properties of ionic redox species generated are also investigated. At the last part of this account, we show some aspects of a singlet biradicaloid character that originates from a small HOMO–LUMO gap.
A New Application of High-Viscosity Kinetics. An Attempt to Identify a Site of Solvent Reorganizations around a Reactant
Authors: Sugita Keijiro , Goto Yoshitaka , Ono Mikiko , Yamashita Kazumi , Hayase Kayoko , Takahashi Toru , Ohga Yasushi , Asano Tsutomu 
Published: October 2004

Abstract
Thermal fading of a colored species photochemically generated from so-called chromenes was kinetically studied in highly viscous media. The reaction was retarded by an increase in viscosity at viscosities higher than 102 Pa s. We propose to use substituent dependence of this retarding effect as a tool to identify the main site of solvent reorganizations around the reactant molecule in the activation step.
Experimental Evidence of Differences in the Hydrogen-Bonded Structure of Concentrated Aqueous Solutions Involving Dl- and l-Alanine Molecules
Authors: Kameda Yasuo , Sasaki Motoya , Yaegashi Masahiro , Amo Yuko , Usuki Takeshi 
Published: October 2004

Abstract
Time-of-Flight (TOF) and steady state reactor neutron diffraction measurements have been carried out for aqueous 2.5 mol% Dl- and l-alanine solutions in order to investigate the differences in intermolecular hydrogen-bonded structure between solutions involving amino acid molecules with different optical activities. The observed difference functions, Δi(Q) and Δiinter(Q), between observed scattering cross sections for Dl- and l-alanine solutions with a D content of 96.1% exhibit the first peak located at Q = 2 Å−1 followed by oscillatory features extending up to the higher-Q region. The difference distribution function, Δg(r), obtained from the Fourier transform of Δi(Q), clearly indicates negative peaks at r = 2 and 2.5 Å and a positive one at r = 3.5 Å. Partial structure factors, aHH(Q), aXH(Q), and aXX(Q) (X: O, N, C, HM, and HM′, where HM and HM′ denote methyl and methine hydrogen atoms within the alanine molecule, respectively) for 2.5 mol% Dl-alanine solutions are successfully determined from combined analyses of intermolecular interference terms observed for solutions with 96.1, 66.0, and 35.9% exchangeable deuterium content. The nearest neighbor O···Hex and Hex···Hex (Hex: exchangeable hydrogen atom) distances are determined from the least squares fit of the observed partial structure factors, 1.90(1) and 2.48(1) Å, respectively. These values correspond to the positions of negative peaks observed in the present Δg(r) function. The least squares fitting analysis of the observed Δi(Q) revealed that the difference in the coordination number of the nearest neighbor O···Hex and Hex···Hex interactions between the Dl- and l-alanine solutions are −0.031(5) and −0.072(5), respectively. It is concluded that the intermolecular hydrogen bonds among solvent water molecules in the Dl-alanine solution are ca. 2% weaker than those in the l-alanine solution.