bluuebunny/crossref_metadata_2025_split huggingface dataset:
Combined MRI and PET imaging in brain stem mass lesions: diagnostic yield in a series of 30 stereotactically biopsied patients
Authors: Massager Nicolas , David Philippe , Goldman Serge , Pirotte Benoît , Wikler David , Salmon Isabelle , Nagy Nathalie , Brotchi Jacques , Levivier Marc 
Published: May 2009

Object. In the management of brainstem lesions, the place of stereotactic biopsy sampling remains debatable. The authors compared the results of magnetic resonance (MR) imaging, positron emission tomography (PET) scanning, and histological studies obtained in 30 patients who underwent MR imaging— and PET-guided stereotactic biopsy procedures for a brainstem mass lesion.Methods. Between July 1991 and December 1998, 30 patients harboring brainstem mass lesions underwent a stereotactic procedure in which combined MR imaging and PET scanning guidance were used. Positron emission tomography scanning was performed using [18F]fluorodeoxyglucose in 16 patients, methionine in two patients, and both tracers in 12 patients. Definite diagnosis was established on histological examination of the biopsy samples. Interpretation of MR imaging findings only or PET findings only was in agreement with the histological diagnosis in 63% and 73% of cases, respectively. Magnetic resonance imaging and PET findings were concordant in 19 of the 30 cases; in those cases, imaging data correlated with histological findings in 79%. Treatment based on information derived from MR imaging was concordant with therapy based on histological findings in only 17 patients (57%). Combining MR imaging and PET scanning data, the concordance between the neuroimaging-based treatment and treatments based on histological findings increased to 19 patients (63%). In seven patients who underwent biopsy procedures with one PET-defined and one MR imaging—defined trajectory, at histological examination the PET-guided samples were more representative of the tumor's nature and grade than the MR imaging—guided samples in four cases (57%). In 18 patients PET scanning was used to define a biopsy target and provided a diagnostic yield in 100% of the cases.Conclusions. Although the use of combined PET and MR imaging improves radiological interpretation of a mass lesion in the brainstem, it does not accurately replace histological diagnosis that is provided by a stereotactically obtained biopsy sample. Combining information provided by MR imaging and PET scanning in stereotactic conditions improves the accuracy of targeting and the diagnostic yield of the biopsy sample; an MR imaging— and PET-guided stereotactic biopsy procedure is a safe and efficient modality for the management of mass lesions of the brainstem.
Long-term natural history of hemorrhagic type moyamoya disease in 42 patients
Authors: Kobayashi Eiichi , Saeki Naokatsu , Oishi Hiromichi , Hirai Shinji , Yamaura Akira 
Published: May 2009

Object. The purpose of this study was to delineate the long-term natural history of hemorrhagic moyamoya disease (MMD).Methods. A retrospective review was conducted among 42 patients suffering from hemorrhagic MMD who had been treated conservatively without bypass surgery. The group included four patients who had undergone indirect bypass surgery after an episode of rebleeding. The follow-up period averaged 80.6 months. The clinical features of the first bleeding episode and repeated bleeding episodes were analyzed to determine the risk factors of rebleeding and poor outcome.Intraventricular hemorrhage with or without intracerebral hemorrhage was a dominant finding on computerized tomography scans during the first bleeding episode in 29 cases (69%). During the follow-up period, 14 patients experienced a second episode of bleeding, which occurred 10 years or longer after the original hemorrhage in five cases (35.7%). The annual rebleeding rate was 7.09%/person/year. The second bleeding episode was characterized by a change in which hemisphere bleeding occurred in three cases (21.4%) and by the type of bleeding in seven cases (50%). After rebleeding the rate of good recovery fell from 45.5% to 21.4% and the mortality rate rose from 6.8% to 28.6%. Rebleeding and patient age were statistically significant risk factors of poor outcome. All four patients in whom there was indirect revascularization after the second bleeding episode experienced a repeated bleeding episode within 8 years.Conclusions. The occurrence of rebleeding a long time after the first hemorrhagic episode was not uncommon. Furthermore, the change in which hemisphere and the type of bleeding that occurred after the first episode suggested the difficulty encountered in the prevention of repeated hemorrhage.
Dynamic nature of cavernous malformations: a prospective magnetic resonance imaging study with volumetric analysis
Authors: Clatterbuck Richard E. , Moriarity John L. , Elmaci Ilhan , Lee Roland R. , Breiter Steven N. , Rigamonti Daniele 
Published: May 2009

Object. Although cavernous malformations (CMs) are not detected in angiographic studies, they have a characteristic appearance on magnetic resonance (MR) images. A number of reports published in the last decade have focused on the behavior of these lesions within the clinical environment. However, little has been published about the evolution of CMs over time, as observed in imaging studies. To understand imaging-documented changes in CMs over time, we analyzed MR images of 114 cavernous malformations in 68 patients who were followed prospectively.Methods. For each CM the location, volume, and MR imaging signal characteristics were recorded. Volume data were available for 107 lesions from initial images. The mean volume of these 107 CMs was 2779 mm3. The lesions ranged in size from 0.5 to 46,533 mm3 (46.5 cm3). Volume data from a second set of images were available for 76 CMs (mean interval from first imaging session 26 months), and from a third set of images for 24 lesions (mean interval from second imaging session 18 months). Over the first follow-up interval, the mean volume change was −991 mm3 (a decrease of approximately 1 cm3) and over the second interval the mean volume change was −642 mm3. Although these mean volume changes appear modest, volume changes in single lesions during follow-up intervals were more dramatic, with decreases as large as 45,629 mm3 (45.6 cm3) and increases as large as 6,074 mm3 (6 cm3). Serial examinations of the MR imaging signal characteristics of these CMs demonstrate a trend for maturation of blood products from a subacute, to a mixed, and finally to a chronic appearance. Three lesions appeared de novo during the follow-up period.Conclusions. On the basis of their analysis, the authors conclude that CMs exhibit a range of dynamic behaviors including enlargement, regression, and de novo formation, as well as progression through a series of characteristic MR imaging appearances.
Volumetric reduction in caudate nucleus following stereotactic lesions of anterior cingulate cortex in humans: a morphometric magnetic resonance imaging study
Authors: Rauch Scott L. , Kim Hackjin , Makris Nikos , Cosgrove G. Rees , Cassem Edwin H. , Savage Cary R. , Price Bruce H. , Nierenberg Andrew A. , Shera David , Baer Lee , Buchbinder Bradley , Caviness Verne S. , Jenike Michael A. , Kennedy David N. 
Published: May 2009

Object. The goal of this study was to test hypotheses regarding changes in volume in subcortical structures following anterior cingulotomy.Methods. Morphometric magnetic resonance (MR) imaging methods were used to assess volume reductions in subcortical regions following anterior cingulate lesioning in nine patients. Magnetic resonance imaging data obtained before and 9 ± 6 months following anterior cingulotomy were subjected to segmentation and subcortical parcellation.Significant volume reductions were predicted and found bilaterally within the caudate nucleus, but not in the amygdala, thalamus, lenticular nuclei, or hippocampus. Subcortical parcellation revealed that the volume reduction in the caudate nucleus was principally referrable to the body, rather than the head. Furthermore, the magnitude of volume reduction in the caudate body was significantly correlated with total lesion volume.Conclusions. Taken together, these findings implicate significant connectivity between a region of anterior cingulate cortex (ACC) lesioned during cingulotomy and the caudate body. This unique data set complements published findings in nonhuman primates, and advances our knowledge regarding patterns of cortical—subcortical connectivity involving the ACC in humans. Moreover, these findings indicate changes distant from the site of anterior cingulotomy lesions that may play a role in the clinical response to this neurosurgical procedure.
Subnecrotic stereotactic radiosurgery controls epilepsy produced by kainic acid injection in rats
Authors: Maesawa Satoshi , Kondziolka Douglas , Dixon C. Edward , Balzer Jeffrey , Fellows Wendy , Lunsford L. Dade 
Published: May 2009

Object. Any analysis of the potential role of stereotactic radiosurgery for epilepsy requires the experimental study of its potential antiepileptogenic, behavioral, and histological effects. The authors hypothesized that radiosurgery performed using subnecrotic tissue doses would reduce or abolish epilepsy without causing demonstrable behavioral side effects. The kainic acid model in rats was chosen to test this hypothesis.Methods. Chronic epilepsy was successfully created by stereotactic injection of kainic acid (8 µg) into the rat hippocampus. Epileptic rats were divided into three groups: high-dose radiosurgery (60 Gy, 16 animals), low-dose (30 Gy, 15 animals), and controls. After chronic epilepsy was confirmed by observation of the seizure pattern and by using electroencephalography (EEG), radiosurgery was performed on Day 10 postinjection. Serial seizure and behavior observation was supplemented by weekly EEG sessions performed for the next 11 weeks. To detect behavioral deficits, the Morris water maze test was performed during Week 12 to study spatial learning and memory. Tasks involved a hidden platform, a visible platform, and a probe trial.After radiosurgery, the incidence of observed and EEG-defined seizures was markedly reduced in rats from either radiosurgically treated group. A significant reduction was noted after high-dose (60 Gy) radiosurgery in Weeks 5 to 9 (p < 0.003). After low-dose (30 Gy) radiosurgery, a significant reduction was found after 7 to 9 weeks (p < 0.04). During the task involving the hidden platform, kainic acid—injected rats displayed significantly prolonged latencies compared with those of control animals (p < 0.05). Hippocampal radiosurgery did not worsen this performance. The probe trial showed that kainic acid—injected rats that did not undergo radiosurgery spent significantly less time than control rats in the target quadrant (p = 0.03). Rats that had undergone radiosurgery displayed no difference compared with control rats and demonstrated better performance than rats that received kainic acid alone (p = 0.04). Radiosurgery caused no adverse histological effects.Conclusions. In a rat model, radiosurgery performed with subnecrotic tissue doses controlled epilepsy without causing subsequent behavioral impairment.
Effects of potassium channel inhibitors on the relaxation induced by the NO donor DEA/NO in isolated human cerebral arteries
Authors: Hempelmann Ralf G. , Seebeck Jörg , Ziegler Albrecht , Mehdorn H. Maximilian 
Published: May 2009

Object. The goal of this study was to investigate whether K+ channels are involved in nitric oxide (NO)—induced relaxation of isolated human cerebral arteries.Methods. Successive concentration—response curves relating to the use of the NO donor diethylamine NO (DEA/NO) were established in the absence and presence of different K+ channel inhibitors after mounting human cerebral arteries onto a wire myograph. The arteries were obtained from macroscopically intact tissue that had been removed during brain tumor operations.A high K+ concentration partially inhibited the relaxant effects of DEA/NO. Different K+ channel inhibitors (tetraethylammonium [TEA], 10−3 M; charybdotoxin, 10−7 M; glibenclamide, 10−6 M; 4-aminopyridine [4-AP], 10−3 M; BaCl2, 5 × 10−5 M; and apamin, 10−6 M) alone failed to affect the responses to DEA/NO. However, a combination of TEA, glibenclamide, 4-AP, and BaCl2 partially blocked the relaxant effects of DEA/NO. In addition, the effects of DEA/NO were inhibited by the thromboxane A2 analog U46619 (3 × 10−7 M).Conclusions. Inhibitors of the large-conductance or small-conductance Ca++-activated K+ channels, the adenosine triphosphate— sensitive K+ channels, and the delayed-rectifier or inward-rectifier K+ channels failed to alter the effects of DEA/NO when only one K+ channel blocker was used. However, a regimen of a combination of K+ channel blockers that possess selectivity for different channels demonstrated that different K+ channel types are involved; these channels may function in a redundant manner and compensate for each other. Selective thromboxane A2 agonists are capable of inhibiting the relaxant response to the NO donor.
Linear accelerator radiosurgery for vestibular schwannoma
Authors: Spiegelmann Roberto , Lidar Zvi , Gofman Jana , Alezra Dror , Hadani Moshe , Pfeffer Raphael 
Published: May 2009

Object. The use of radiosurgery in the treatment of acoustic neuromas has increased substantially during the last decade. Most published experience relates to the use of the gamma knife. In this report, the authors review the methods and results of linear accelerator (LINAC) radiosurgery in 44 patients with acoustic neuromas who were treated between 1993 and 1997.
Methods. Computerized tomography scanning was selected as the stereotactic imaging modality for target definition. A single, conformally shaped isocenter was used in the treatment of 40 patients; two or three isocenters were used in four patients who harbored very irregular tumors. The radiation dose directed to the tumor border was the only parameter that changed during the study period: in the first 24 patients who were treated the dose was 15 to 20 Gy, whereas in the last 20 patients the dose was reduced to 11 to 14 Gy. After a mean follow-up period of 32 months (range 12–60 months), 98% of the tumors were controlled. The actuarial hearing preservation rate was 71%. New transient facial neuropathy developed in 24% of the patients and persisted to a mild degree in 8%. Radiation dose correlated significantly with the incidence of cranial neuropathy, particularly in large tumors (≥ 4 cm3).
Conclusions. Single-isocenter LINAC radiosurgery proved to be an effective treatment for acoustic neuromas in this series, with results that were comparable with those reported for gamma knife radiosurgery and multiple isocenters.
Surgical treatment for neocortical temporal lobe epilepsy: clinical and surgical aspects and seizure outcome
Authors: Schramm Johannes , Kral Thomas , Grunwald Thomas , Blümcke Ingmar 
Published: May 2009

Object. The goal of this paper was to describe the clinical and surgical aspects of a group of patients suffering from drug-resistant neocortical temporal lobe epilepsy (TLE), as well as seizure outcomes and factors affecting seizure outcomes in these patients.
Methods. This study was based on data prospectively collected and retrospectively evaluated. Sixty-two patients with neocortical TLE constituted the study population. Only patients who underwent corticectomies, lesionectomies, lateral anterior lobe resections, and/or multiple subpial transections were included. The pathological areas resected in these patients could be separated into three groups composed of 35 neoplastic lesions, 23 nonneoplastic lesions, and three nonlesional areas. The mean duration of follow-up review in these patients was 21.9 ± 14 months.
Outcomes were categorized according to Engel classes. Class I was found in 79% of the patients and Class II in 11%. Invasive presurgical evaluation was performed in 43% of the patients. There were only temporary complications (3.3% surgical and 1.6% neurological) and no deaths. In summary, lesions confirmed on histological examination were rarely found in patients with neocortical TLE. Low-grade tumors were the most commonly found lesions in these patients and the most common tumor was ganglioglioma. Outcome was best for those patients with neoplastic lesions and was independent of the duration of their seizures. Outcome was little influenced by the type of resection performed and was found to be as good as that achieved in patients with mesial TLE.
Conclusions. These results demonstrate that the concept of lateral or neocortical TLE as a distinct entity is useful. Surgery for neocortical TLE can be considered a viable treatment option that is associated with a low morbidity rate and good outcomes.
Analysis of the results obtained in 120 patients with large acoustic neuromas surgically treated via the translabyrinthine—transtentorial approach
Authors: Sluyter Steven , Graamans Kees , Tulleken Cornelis A. F. , Van Veelen Cornelis W. M. 
Published: May 2009

Object. The authors review the results of a series of 120 acoustic neuromas that were surgically treated via the translabyrinthine-transtentorial approach between 1986 and 1999.
Methods. The authors retrospectively evaluated a series of 120 acoustic neuromas with extrameatal diameters of 2 cm or greater, 99 (82.5%) of which had diameters longer than 3 cm. Complete tumor removal, as ascertained using computerized tomography or magnetic resonance imaging, was achieved in 110 patients (91.7%). The facial nerve was anatomically preserved in 97 patients (80.8%). The main postoperative complications were cerebrospinal fluid (CSF) leakage through the scalp wound (13.3%) requiring surgical revision in 2.5%, meningitis (9.2%), CSF rhinorrhea (6.7%) requiring surgical revision in 2.5%, and epileptic seizures (the only permanent complication) requiring medication (3.3%). There was no death directly related to the surgery. Long-term follow-up examination of the facial nerve revealed recovery of function to the level of House—Brackmann Grade I or II in 56.2% of the patients.
Conclusions. The results and complications presented in this series are comparable to those reported in the literature. The authors conclude that the combined translabyrinthine—transtentorial approach is a safe route for removing acoustic neuromas with a diameter of 2 cm or greater.
Frameless neuronavigation in intracranial endoscopic neurosurgery
Authors: Schroeder Henry W. S. , Wagner Wolfgang , Tschiltschke Wolfgang , Gaab Michael R. 
Published: May 2009

Object. Frameless computerized neuronavigation has been increasingly used in intracranial endoscopic neurosurgery. However, clear indications for the application of neuronavigation in neuroendoscopy have not yet been defined. The purpose of this study was to determine in which intracranial neuroendoscopic procedures frameless neuronavigation is necessary and really beneficial compared with a free-hand endoscopic approach.
Methods. A frameless infrared-based computerized neuronavigation system was used in 44 patients who underwent intracranial endoscopic procedures, including 13 third ventriculostomies, nine aqueductoplasties, eight intraventricular tumor biopsy procedures or resections, six cystocisternostomies in arachnoid cysts, five colloid cyst removals, four septostomies in multiloculated hydrocephalus, four cystoventriculostomies in intraparenchymal cysts, two aqueductal stent placements, and fenestration of one pineal cyst and one cavum veli interpositi. All interventions were successfully accomplished. In all procedures, the navigational system guided the surgeons precisely to the target. Navigational tracking was helpful in entering small ventricles, in approaching the posterior third ventricle when the foramen of Monro was narrow, and in selecting the best approach to colloid cysts. Neuronavigation was essential in some cystic lesions lacking clear landmarks, such as intraparenchymal cysts or multiloculated hydrocephalus. Neuronavigation was not necessary in standard third ventriculostomies, tumor biopsy procedures, and large sylvian arachnoid cysts, or for approaching the posterior third ventricle when the foramen of Monro was enlarged.
Conclusions. Frameless neuronavigation has proven to be accurate, reliable, and extremely useful in selected intracranial neuroendoscopic procedures. Image-guided neuroendoscopy improved the accuracy of the endoscopic approach and minimized brain trauma.
Interleukin-6 overexpression as a marker of malignancy in human gliomas
Authors: Rolhion Christine , Penault-Llorca Frédérique , Kémény Jean-Louis , Lemaire Jean-Jacques , Jullien Christiane , Labit-Bouvier Corinne , Finat-Duclos Françoise , Verrelle Pierre 
Published: May 2009

Object. Glioblastomas multiforme (GBMs) grow rapidly and are highly resistant to treatment compared with other glioma types and grades. Consequently, it is of major interest to identify markers of aggressiveness in these tumors that could represent new therapeutic targets. Interleukin (IL)—6 is frequently produced in gliomas and, given its manifold properties, could be considered as a candidate marker. Expression of IL-6 may be involved in cell growth, resistance to chemotherapy and radiotherapy (via an antiapoptotic pathway), and angiogenesis. This study was conducted to test this hypotheses and to evaluate the suitability of IL-6 as a target in the treatment of GBMs.
Methods. The authors studied the relationship between the level of IL-6 gene expression as assessed using semiquantitative reverse transcription—polymerase chain reaction and by determining various histological types and grades in a series of 59 gliomas. It was found that GBMs displayed a significantly higher level of IL-6 expression than other types of glioma (p < 0.001). Immunohistochemical analysis revealed that IL-6 was produced mainly by malignant cells and a few vascular endothelial cells.
Conclusions. It can be inferred from these findings that IL-6 gene expression is related to glioma aggressiveness and that IL-6 may play a central role in GBM behavior. Interleukin-6, therefore, could be considered as a new potential target in the treatment of GBMs.