bluuebunny/crossref_metadata_2025 huggingface dataset:
Autologous adult human Schwann cells genetically modified to provide alternative cellular transplants in peripheral nerve regeneration
Authors: Haastert Kirsten , Mauritz Christina , Matthies Cordula , Grothe Claudia
Published: January 2008

Object

The purpose of this study was to provide genetically modified adult human Schwann cells as tools for cell transplantation in peripheral nerve repair. The application of transfected autologous Schwann cells overexpressing regeneration-promoting proteins, for example, neurotrophic or growth factors, is a promising approach in the aforementioned context. To achieve an optimal clinical outcome, it is highly important to perform enrichment, genetic modification, and retransplantation of cells in a short time.

Methods

To enable the development of these autologous cellular prostheses, the authors tested the properties of adult human Schwann cells obtained from differently treated human peripheral nerve biopsy samples. The use of “cold jet,” a fast and effective enrichment procedure, as well as selective, serum-free culture conditions, resulted in very pure adult human Schwann cell cultures. Using an optimized electroporation protocol, as many as 48.4% of adult human Schwann cells were successfully transfected.

Conclusions

The authors present a very fast protocol to establish adult human Schwann cell cultures that demonstrably express plasmid proteins after plasmid DNA insertion by electroporation. These autologous human Schwann cells transfected to enhance the endogenous production of regeneration-supporting proteins will likely constitute a major component of tissue-engineered peripheral nerve grafts.
Superficial surgical landmarks for identifying the posterior interosseous nerve
Authors: Tubbs R. Shane , Salter E. George , Wellons John C. , Blount Jeffrey P. , Oakes W. Jerry
Published: January 2008

Object

There is a paucity of information in the neurosurgical literature regarding the surgical anatomy surrounding the posterior interosseous nerve (PIN). The goal of the current study was to provide easily recognizable superficial bone landmarks for identification of the PIN.

Methods

Thirty-four cadaveric upper extremities obtained from adults were subjected to dissection of the PINs, and measurements were made between this nerve and surrounding superficial bone landmarks.

In all specimens the main radial trunk was found to branch into its superficial branch and PIN at the level of the lateral epicondyle of the humerus. Proximally, the PIN was best identified following dissection between the brachioradialis and extensor carpi radialis longus and brevis muscles. At its exit site from the supinator muscle, the PIN was best identified after retraction between the extensor carpi radialis longus and brevis and extensor digitorum communis muscles. This site was a mean distance of 6 cm distal to the lateral epicondyle of the humerus. No compression of the PIN by the tendon of origin of the extensor carpi radialis brevis muscle was seen. One specimen was found to have a proximally split PIN that provided a previously undefined articular branch to the elbow joint. The mean diameter of the PIN proximal to the supinator muscle was 4.5 mm. The leash of Henry crossed the PIN in all but one specimen and was found at a mean distance of 5 cm inferior to the lateral epicondyle. The PIN exited the distal edge of the supinator muscle at a mean distance of 12 cm distal to the lateral epicondyle of the humerus. Here the mean diameter of the PIN was 4 mm. The exit site from the distal edge of the supinator was found to be at a mean distance of 18 cm proximal to the styloid process of the ulna. This exit site for the PIN was best identified following dissection between the extensor carpi radialis longus and brevis and extensor digitorum communis muscles. The distal articular branch of the PIN was found to have a mean length of 13 cm and the proximal portion of this terminal segment was located at a mean distance of 7.5 cm proximal to the Lister tubercle.

Conclusions

The addition of more anatomical landmarks can help the neurosurgeon to be more precise in identifying the PIN and in avoiding complications during surgery in this region.
Conduction aphasia as a function of the dominant posterior perisylvian cortex
Authors: Quigg Mark , Geldmacher David S. , Elias W. Jeff
Published: January 2008

✓ Assessment of eloquent functions during brain mapping usually relies on testing reading, speech, and comprehension to uncover transient deficits during electrical stimulation. These tests stem from findings predicted by the Geschwind–Wernicke hypothesis of receptive and expressive cortices connected by white matter tracts. Later work, however, has emphasized cortical mechanisms of language function. The authors report two cases that demonstrate that conduction aphasia is cortically mediated and can be inadequately assessed if not specifically evaluated during brain mapping.

To determine the distribution of language on the dominant cortex, electrical cortical stimulation was performed in two cases by using implanted subdural electrodes during brain mapping before epilepsy surgery. A transient isolated deficit in repetition of language was reported during stimulation of the posterior portion of the dominant superior temporal gyrus in one patient and during stimulation of the supramarginal gyrus in the other patient.

These cases demonstrate a localization of language repetition to the posterior perisylvian cortex. Brain mapping of this region should include assessment of verbal repetition to avoid potential deficits resembling conduction aphasia.
Gamma knife surgery for dural arteriovenous shunts: 25 years of experience
Authors: Söderman Michael , Edner Göran , Ericson Kaj , Karlsson Bengt , Rähn Tiit , Ulfarsson Elfar , Andersson Tommy
Published: January 2008

Object

The aim of this study was to assess the clinical efficacy of gamma knife surgery (GKS) in the treatment of dural arteriovenous shunts (DAVSs).

Methods

From a database of more than 1600 patients with intracranial arteriovenous shunts that had been treated with GKS, the authors retrospectively and prospectively identified 53 patients with 58 DAVSs from the period between 1978 and 2003. Four patients were lost to follow-up evaluation and were excluded from the series. Thus, this study is based on the remaining 49 patients with 52 DAVSs. Thirty-six of the shunts drained into the cortical venous system, either directly or indirectly, and 22 of these were associated with intracranial hemorrhage on patient presentation. The mean prescription radiation dose was 22 Gy (range 10–28 Gy).

All patients underwent a clinical follow-up examination. In 41 cases of DAVS a follow-up angiography study was performed. At the 2-year follow-up visit, 28 cases (68%) had angiographically proven obliteration of the shunt and in another 10 cases (24%) there was significant flow regression. Three shunts remained unchanged.

There was one immediate minor complication related to the administration of radiation. Furthermore, one patient had a radiation-induced complication 10 years after treatment, although she recovered completely. There was one posterior fossa bleed 2 months after radiosurgery; a hematoma, as well as a lesion, was evacuated, and the patient recovered uneventfully. A second patient had an asymptomatic occipital hemorrhage approximately 6 months postradiosurgery.

The clinical outcome after GKS was significantly better than that in patients with naturally progressing shunts (p < 0.01, chi-square test); figures on the latter have been reported previously.

Conclusions

Gamma knife surgery is an effective treatment for DAVSs, with a low risk of complications. Major disadvantages of this therapy include the time elapsed before obliteration and the possibility that not all shunts will be obliterated. Cortical venous drainage from a DAVS, a risk factor for intracranial hemorrhage, is therefore a relative contraindication. Consequently, GKS can be used in the treatment of both benign DAVSs with subjectively intolerable bruit and aggressive DAVSs not responsive to endovascular treatment or surgery.
Gamma surgery in the treatment of nonsecretory pituitary macroadenoma
Authors: Mingione Vincenzo , Yen Chun Po , Vance Mary Lee , Steiner Melita , Sheehan Jason , Laws Edward R. , Steiner Ladislau
Published: January 2008

Object

The authors report on a retrospective analysis of the imaging and clinical outcomes following gamma surgery in 100 patients with nonsecretory pituitary macroadenoma.

Methods

Between June 1989 and March 2004, 100 consecutive patients with nonsecretory pituitary macroadenoma were treated at the Lars Leksell Center for Gamma Surgery, University of Virginia Health System (Charlottesville, VA). Ninety-two patients had residual or recurrent macroadenoma following one or more surgical procedures. In eight patients, gamma surgery was the primary treatment. Ten patients received conventional fractionated radiotherapy before the gamma surgery. Sixty-nine patients required hormone replacement therapy for one or more deficits before gamma knife treatment. Peripheral doses between 5 and 25 Gy (mean 18.5 Gy) were administered.

Imaging and endocrinological follow-up evaluations were performed in 90 patients; these studies ranged from 6 to 142 months (mean 44.9 months) and 6 to 127 months (mean 47.9 months), respectively. Tumor volume decreased in 59 patients (65.6%), remained unchanged in 24 (26.7%), and increased in seven (7.8%). The minimal effective peripheral dose was 12 Gy; peripheral doses greater than 20 Gy did not seem to provide additional benefit. Of 61 patients with a partially or fully functioning pituitary gland and follow-up data, 12 (19.7%) suffered new hormone deficits following gamma surgery. In patients with endocrinological follow-up data that had been collected over more than 2 years, the rate of new deficits was 25%. No neurological morbidity or death was related to treatment.

Conclusions

Current experience suggests that gamma surgery is an appropriate means of managing recurrent or residual nonsecretory pituitary macroadenoma following microsurgery and a primary treatment in selected patients. To evaluate definite rates of recurrence and new endocrine deficiencies, long-term follow-up studies are needed.
Natural course of incidentally found nonfunctioning pituitary adenoma, with special reference to pituitary apoplexy during follow-up examination
Authors: Arita Kazunori , Tominaga Atsushi , Sugiyama Kazuhiko , Eguchi Kuniki , Iida Koji , Sumida Masayuki , Migita Keisuke , Kurisu Kaoru
Published: January 2008

Object

The increase in the incidental detection of asymptomatic pituitary adenomas, known as “pituitary inciden-talomas,” led the authors to conduct a survey of the natural course of these lesions.

Methods

Forty-two patients with clinically nonfunctioning pituitary adenomas who had manifested no neurological or endocrinological disorders were monitored with magnetic resonance imaging studies. The follow-up period ranged from 10.8 to 168.2 months (mean ± standard deviation, 61.9 ± 38.2 months). The mean initial tumor size was 18.3 ± 7 mm.

In 21 patients, the tumor increased by at least 10% of its measured size on detection. This increase was first detected between 8.4 and 58.8 months (mean 31.8 ± 17.6 months) after diagnosis. There was no correlation between the original tumor size, patient age, or the presence of intratumoral cysts and tumor growth. Symptoms were noted in 10 patients during follow up; in four, extensive tumor necrosis accompanied hemorrhage, leading to severe headache, acute ophthalmological symptoms, and panhypopituitarism, which was indicative of pituitary apoplexy. Transsphenoidal surgery was performed in 12 patients with enlarged tumors, including three with apoplexy. With the exception of one apoplectic patient, visual function was recovered in all who underwent surgery. All apoplectic patients continue to manifest hypopituitarism.

Conclusions

In the course of 4 years, the size of the incidentalomas increased in 40% of 42 patients and became symptomatic in 20%. During the 5-year follow up, pituitary apoplexy developed in 9.5%. These findings may justify early intervention, especially in young individuals with incidentally found macroadenoma.
Endovascular operating suite: future directions for treating neurovascular disease
Authors: Murayama Yuichi , Saguchi Takayuki , Ishibashi Toshihiro , Ebara Masaki , Takao Hiroyuki , Irie Koreaki , Ikeuchi Satoshi , Onoue Hisashi , Ogawa Takeki , Abe Toshiaki
Published: January 2008

Object

The purpose of this study was to evaluate initial experiences in a surgical operating room (OR) with a multi-purpose angiography unit, which offers integrated neurosurgical and radiological capabilities.

Methods

A specially designed biplane digital subtraction (DS) angiography system was installed in the neurosurgery OR. The new suite, which allows three-dimensional DS angiography with C-arm for computerized tomography and microsurgery capabilities, allows the neurosurgeon to perform a wide range of neurosurgical and endovascular procedures. Three hundred thirty-two procedures were performed in the endovascular OR between November 2003 and March 2005. Patients arriving in the emergency department were transferred to the endovascular OR without delay. The neurovascular team performed diagnostic angiography followed by endovascular interventional procedures or surgery.

Conclusions

The newly designed endovascular OR facilitates safe and systemic treatment of neurovascular disease.
Sequential and spatial profiles of apoptosis in ischemic penumbra after two-vein occlusion in rats
Authors: Nishioka Toshikazu , Nakase Hiroyuki , Nakamura Mitsutoshi , Konishi Noboru , Sakaki Toshisuke
Published: January 2008

Object

The two-vein occlusion model is known to be useful for ischemic penumbra studies in vivo. It was applied here to examine sequential changes in the expression of Bax and Bcl-2 proteins and in apoptotic cells to assess the relationship between penumbra and apoptosis.

Methods

Two cortical veins were occluded photochemically by using rose bengal dye in 27 Wistar rats. The animals were killed with perfusion fixation at the following intervals: 4, 12, 24, 48, 96, and 168 hours after vein occlusion (four at each interval; three additional rats were sham-treated). Immunohistochemical analysis for the Bcl-2 family of proteins was performed along with the terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay to examine the relationship to single-cell death.

Cells positive for antiapoptotic proteins began to appear in the TUNEL assay for animals killed 24 hours after vein occlusion, with a peak at 48 hours. These cells were localized in the core of infarction. Immunohistochemical staining for Bax protein showed an increased presence around ischemic lesions at 4 hours after vein occlusion, and the amounts continued to rise until 24 hours, when the localization was diffuse around the core of infarction. Negative findings on immunohistochemical studies for Bcl-2 protein were seen at the early phase after two-vein occlusion.

Conclusions

After vein occlusion, apoptosis appeared sequentially and widely in cortical lesions considered to be the penumbra. Therefore, control of apoptosis would be expected to offer a therapeutic window for treatment of venous infarction.
Anatomical and quantitative description of the transcavernous approach to interpeduncular and prepontine cisterns
Authors: Figueiredo Eberval Gadelha , Zabramski Joseph M. , Deshmukh Pushpa , Crawford Neil R. , Preul Mark C. , Spetzler Robert F.
Published: January 2008

Object

The management of wide-necked, giant, or unsuccessfully coil-treated basilar apex aneurysms requires a wide exposure, for both working area and linear visualization of the basilar artery (BA). Cranial-based approaches, such as the transcavernous approach, have been proposed to deal with such aneurysms; whether abbreviated forms of this approach might provide similar exposure remains controversial. The authors examine this issue quantitatively.

Methods

Four alcohol-preserved cadaveric heads injected with pigmented silicone were prepared for bilateral dissection. After completing an orbitozygomatic craniotomy, the surgeons worked in a reverse direction, performing the transcavernous approach in five steps: 1) posterior clinoidectomy; 2) cavernous sinus opening; 3) anterior clinoidectomy; 4) cutting of the distal dural ring; and 5) cutting of the proximal dural ring.

Performing the complete transcavernous approach significantly increased the working area and linear exposure of the BA compared with abbreviated forms of the approach (p < 0.05). Opening the roof of the cavernous sinus significantly increased the working area compared with posterior clinoidectomy alone (p = 0.014); however, additional gains in exposure required completing the transcavernous approach. Resection of the anterior clinoid process combined with opening of only the distal dural ring did not significantly increase the working area or linear exposure of the BA.

Conclusions

The complete transcavernous approach significantly increases the working area and linear exposure of the BA compared with the more conservative forms of approach.
Treatment of a middle cerebral artery giant aneurysm using a covered stent
Authors: Pero Guglielmo , Denegri Federica , Valvassori Luca , Boccardi Edoardo , Scialfa Giuseppe
Published: January 2008

✓ The authors report the case of a 60-year-old man harboring a wide-necked giant aneurysm of the M1 segment of the left middle cerebral artery (MCA); his symptoms included transient ischemic attacks characterized by right hemiparesis and aphasia. The aneurysm was treated by placing a covered stent across the orifice of the aneurysm. The 18-month follow-up examination showed a very good outcome, with perfect left MCA patency, no new ischemic lesion, and minor residual aphasia and right hemiparesis. This is the first report in the literature of an MCA aneurysm treated using a covered stent.
Traumatic carotid artery–cavernous sinus fistula treated with a covered stent
Authors: Madan Anoop , Mujic Asim , Daniels Katie , Hunn Andrew , Liddell John , Rosenfeld Jeffrey V.
Published: January 2008

✓ The authors describe the cases of two patients with unilateral traumatic caroticocavernous fistulas in whom a self-expanding covered stent was successfully used to obliterate the fistula after failed occlusion with detachable balloons and coils. They discuss this option as a primary therapeutic modality in cases in which detachable balloons or coils, with or without a bare stent, have failed to obliterate the fistula. The placement of a covered stent to occlude the lesion from the outset may represent a new therapeutic approach to the treatment of these lesions.
Microcatheter pull-up technique in the transvenous embolization of an isolated sinus dural arteriovenous fistula
Authors: Hanaoka Mami , Satoh Koichi , Satomi Junichiro , Matsubara Shunji , Nagahiro Shinji , Takimoto Osamu , Ohbayashi Masaaki
Published: January 2008

✓ The authors describe a novel technique involving the use of a gooseneck snare for microcatheterization of isolated sinus dural arteriovenous fistulas (DAVFs). In some patients the inferior petrosal and transverse–sigmoid sinuses, the route of transvenous embolization (TVE) for DAVF, are separated by several channels. Even if a guidewire can be passed over the occluded portion and the affected sinus can be accessed, one may not necessarily be able to insert a microcatheter. The authors report on three patients who underwent successful microcatheterization via a novel pull-up technique, which makes use of a gooseneck snare to perform TVE even in very difficult circumstances.
Decompression of cavernous sinus meningioma for preservation and improvement of cranial nerve function
Authors: Couldwell William T. , Kan Peter , Liu James K. , Apfelbaum Ronald I.
Published: January 2008

✓ Meningiomas are the most common tumors affecting the cavernous sinus (CS). Despite advances in microsurgery and radiosurgery, treatment of CS meningiomas remains difficult and controversial. As in cases of other meningiomas, the goal of treatment for CS meningioma is long-term growth control and preservation of neural function. Gross-total resection, the ideal treatment for meningioma, is not always possible to obtain in patients with CS meningiomas with an acceptable level of morbidity. Therefore, microsurgery and radiosurgery have recently been advocated as a combined therapy to achieve good control of tumor growth and favorable functional outcome. The authors describe a technique in which tumor volume can be reduced to a minimal residual amount, while preserving cranial nerve function. This enables the smallest field to be treated radiosurgically. The optic nerve is decompressed, and the tumor mass is reduced to provide at least a 5-mm interpositional distance between the optic nerve and the residual lesion. Direct decompression of the CS, with opening of the lateral and superior sinus walls, and piecemeal removal of the tumor in “safe” locations are performed to facilitate an improvement in cranial nerve function. The authors describe the use of this technique in a series of patients and demonstrate improvement of cranial nerve function in a subset of these patients.
Accurate placement of the distal end of a ventriculoatrial shunt with the aid of real-time transesophageal echocardiography
Authors: Machinis Theofilos G. , Fountas Kostas N. , Hudson John , Robinson Joe Sam , Troup E. Christopher
Published: January 2008

Objective

Ventriculoatrial (VA) shunts remain a valid option for the treatment of hydrocephalus, especially in patients in whom ventriculoperitoneal (VP) shunts fail. Correct positioning of the distal end of the catheter in the right atrium is of paramount importance for maintaining shunt patency and reducing the incidence of VA shunt-associated morbidity. The authors present their experience with real-time transesophageal echocardiography (TEE) monitoring for the accurate placement of the distal catheter of a VA shunt.

Methods

Four patients underwent conversion of a VP shunt to a VA shunt under the guidance of intraoperative fluoroscopy and TEE between May 2003 and December 2004. After induction of general anesthesia, the TEE transducer was advanced into the esophagus. A cervical incision was made and the external jugular vein was visualized. An introducer was passed through an opening in the jugular vein and a guidewire was placed through the introducer. Under continuous TEE guidance, the guidewire was carefully advanced into the superior vena cava. A distal shunt catheter overlying a J-wire was then passed to the superior vena cava, again under TEE guidance. The catheter was advanced to the right atrium after removing the guidewire.

Final visualization with TEE and fluoroscopy revealed a good position of the catheter in the right atrium in all four cases. The mean duration of the operation was 91 minutes (range 65–120 minutes) and the mean operative blood loss was 23 ml (range 10–50 ml). No procedure-related complication was noted.

Conclusions

Real-time TEE is a safe and simple technique for the accurate placement of the distal catheter of a VA shunt.
Use of surface electromyography to assess and select patients with idiopathic dystonia for bilateral pallidal stimulation
Authors: Wang Shouyan , Liu Xuguang , Yianni John , Green Alex L. , Joint Carole , Stein John F. , Bain Peter G. , Gregory Ralph , Aziz Tipu Z.
Published: January 2008

Object

The object of this study was to identify a preoperative physiological index by using surface electromyography (EMG) signals that would correlate with clinical outcome in dystonic patients following bilateral pallidal stimulation.

Methods

In 14 patients with spasmodic torticollis, generalized dystonia, and myoclonic dystonia, surface EMG signals were recorded from the most affected muscle groups. Although the dystonia affected different body segments, the EMG signals in all patients could be decomposed into bursting and sustained components. Subsequently, a ratio of the EMG amplitude was calculated between the two components and then correlated with clinical outcome.

Patients who experienced rapid improvement following bilateral pallidal stimulation had a significantly higher EMG ratio compared with those who did not. Furthermore, a significant correlation was found between the EMG ratio and clinical improvement during the 12-month period following pallidal stimulation.

Conclusions

The authors concluded that surface EMG studies could be used to predict the clinical outcome of and to select patients for pallidal stimulation for dystonia.
Evaluation, management, and long-term follow up of vein of Galen malformations
Authors: Gupta Arun Kumar , Rao Vedula Rajani Kanth , Varma Dandu Ravi , Kapilamoorthy Tirur R. , Kesavadas Chandrasekharan , Krishnamoorthy Thamburaj , Thomas Bejoy , Bodhey Narendra K. , Purkayastha Sukalyan
Published: January 2008

Object

Vein of Galen malformations (VGMs) are extremely rare intracranial lesions. Clinical presentation and management strategies vary significantly in different areas of the world. The authors report their experience in evaluation, management, and long-term follow up of these lesions in India.

Methods

Between October 1983 and June 2003, 25 patients with VGMs were referred to the authors’ institution for evaluation and management. Ten children younger than 2 years of age presented with rapidly increasing head size as the chief complaint. Among 11 children 2 years of age or older, the most common presenting symptom was chronic headache. Four patients who presented during adulthood had chronic headache for many years before presentation. Angiographic evaluation of the lesion was performed in 21 patients. Fifteen patients were treated using endovascular techniques. Injection of the embolic material was performed after induction of systemic hypotension when the flow in the fistula was high.

Complete occlusion of the arteriovenous shunt could be achieved in two patients with vein of Galen aneurysmal dilation (100% of patients with this type of malformation) and in five of the six patients with the mural type of malformation (83%). Among patients with the choroidal type of malformation, complete obliteration of the shunt could be achieved in three patients. In three patients with high-flow choroidal malformations, embolization carried out in a single sitting resulted in shunt reduction of nearly 90%. These patients received clinical follow up.

Conclusions

The authors’ experience in evaluation and management of VGMs reveals that in areas of the world where access to dedicated specialist care is limited, the clinical presentation of VGMs can differ appreciably from the classic descriptions in the literature. Endovascular management of these lesions results in excellent angiographic and clinical results.
Volumetric extent of resection and residual contrast enhancement on initial surgery as predictors of outcome in adult patients with hemispheric anaplastic astrocytoma
Authors: Keles G. Evren , Chang Edward F. , Lamborn Kathleen R. , Tihan Tarik , Chang Chih-Ju , Chang Susan M. , Berger Mitchel S.
Published: January 2008

Object

To investigate the prognostic significance of the volumetrically assessed extent of resection on time to tumor progression (TTP), overall survival (OS), and tumor recurrence patterns, the authors retrospectively analyzed preoperative and postoperative tumor volumes in 102 adult patients from the time of the initial resection of a hemispheric anaplastic astrocytoma (AA).

Methods

The quantification of tumor volumes was based on a previously described method involving computerized analysis of magnetic resonance (MR) images. Analysis of contrast-enhancing tumor volumes on T1-weighted MR images was conducted for 67 patients who had contrast-enhancing tumors. Measurements of T2 hyperintensity were obtained for all 102 patients in the study.

The presence or absence of preresection enhancement, actual volume of this enhancement, and the percentage of preoperative enhancement as it relates to the total T2 tumor volume did not have a statistically significant relationship to TTP or OS. In addition to age, the volume of residual disease measured on T2-weighted MR images was the most significant predictor of TTP (p < 0.001), and residual contrast-enhancing tumor volume was the most significant predictor of OS (p = 0.003) on multivariate analysis. In contrast to low-grade gliomas, there was no statistically significant relationship between the extent of resection and histological characteristics at the time of recurrence, that is, tumor Grade III compared with Grade IV.

Conclusions

Data from this retrospective analysis of a histologically uniform group of hemispheric AAs treated in the MR imaging era suggest that residual tumor volumes, as documented on postoperative imaging studies, may be a prognostic factor for TTP and OS for this patient population.
Cellular immunity of patients with malignant glioma: prerequisites for dendritic cell vaccination immunotherapy
Authors: Rapp Marion , Özcan Zakir , Steiger Hans-Jakob , Wernet Peter , Sabel Michael C. , Sorg Rüdiger V.
Published: January 2008

Object

Vaccination therapy that uses dendritic cells (DCs) is a promising immunotherapeutic approach. However, it relies on intact cellular immunity and efficient generation of mature DCs, both of which can be impaired in patients with glioma. Therefore, the immune status and ex vivo generation of DC in such patients were studied.

Methods

The frequencies of white blood cell subsets and monocyte-derived, mature DCs in patients with high-grade gliomas and healthy control volunteers were analyzed using flow cytometry.

In the patients, frequencies of lymphocytes, T cells, and B cells were reduced in comparison with the volunteers in the control group, whereas frequencies of neutrophils and monocytes were increased. There were no differences between the two groups in terms of white blood cell counts or the frequency of NK cells and the major T-cell subsets. The responsiveness of T cells to lectin stimulation was normal. For monocytes, lower frequencies of CD80+ and CD86+ cells but not of CD40+ and HLA-DR+ cells were observed in patients. Ex vivo DC generation in a two-step culture protocol in autologous plasma–supplemented medium or in serum-free medium showed only minor differences in CD80 and HLA-DR expression between the patient and control groups. Frequencies of CD83+, CD1a+, CD14−, CD40+, and CD86+ cells were comparable. Overall, the serum-free medium was superior to the plasma-supplemented medium and allowed efficient ex vivo generation of CD83+, CD1a+, and CD14− mature DCs.

Conclusions

Only minor defects in the immune status of patients with glioma were observed, which probably would not hamper immunotherapy. Mature DCs can be generated successfully in normal numbers and with typical immunophenotypes from monocytes of patients with glioma, particularly under serum-free conditions.
Subtraction ictal single-photon emission computed tomography coregistered to magnetic resonance imaging in evaluating the need for repeated epilepsy surgery
Authors: Wetjen Nicholas M. , Cascino Gregory D. , Fessler A. James , So Elson L. , Buchhalter Jeffrey R. , Mullan Brian P. , O’Brien Terence J. , Meyer Fredric B. , Marsh W. Richard
Published: January 2008

Object

The aim of this study was to determine whether ictal single-photon emission computed tomography (SPECT) is useful in localizing the site of seizure onset in patients in whom surgery for intractable epilepsy failed and who are being considered for repeated surgery.

Methods

Subtraction ictal SPECT coregistered to magnetic resonance imaging (SISCOM) studies were retrospectively analyzed in 58 patients who were being evaluated for possible repeated resection for intractable partial epilepsy between January 1, 1996, and October 31, 1999. All patients had persistent seizures subsequent to an initial resection and underwent another excision. The SISCOM-demonstrated abnormalities were classified as concordant, discordant, or indeterminate, compared with the localization of the epileptogenic zone revealed on video electroencephalography monitoring. The ability of SISCOM to predict operative outcome was also determined in patients who had undergone repeated surgical procedures.

The SISCOM studies revealed a localized hyperperfused alteration in 46 (79%) of 58 patients. Forty-one (89%) of these 46 patients had a SISCOM-demonstrated alteration in the hemisphere of the previous epilepsy surgery. Imaging changes in 33 (72%) of the 46 patients were at the site of the previous focal cortical resection. Eight (17%) of the 46 had SISCOM-demonstrated abnormalities remote from the lobe in which surgery had been performed but in the ipsilateral hemisphere. The hyperperfusion focus was in the contralateral hemisphere in the remaining five patients (11%). The site of the epileptogenic zone was concordant with the SISCOM focus in 32 (70%) of 46 patients. Twenty-six patients underwent repeated resection and were followed up for a mean of 44 months thereafter; 11 of these patients (42%) had a significant reduction in seizure tendency. Only five patients (19%) were seizure free. Ten (50%) of 20 patients with a concordant SISCOM focus compared with none (0%) of three patients with a discordant focus had a favorable surgical outcome (p = 0.23).

Conclusions

The SISCOM method might be useful in the evaluation of, and the surgical planning for, patients with intractable partial epilepsy in whom previous resective treatment has failed and who are being considered for reoperation.
Neurostimulation for chronic noncancer pain: an evaluation of the clinical evidence and recommendations for future trial designs
Authors: Coffey Robert J. , Lozano Andres M.
Published: January 2008

Object

Neurostimulation to treat chronic pain includes approved and investigational therapies directed at the spinal cord, thalamus, periaqueductal or periventricular gray matter, motor cortex, and peripheral nerves. Persistent pain after surgery and work-related or neural injuries are common indications for such treatments. In light of the risks, efforts, costs, and expectations associated with neurostimulation therapies, a careful reexamination of the methods used to gather evidence for this treatment’s long-term efficacy is in order.

Methods

The authors combed English-language publications to determine the nature of the evidence supporting the efficacy of neurostimulation therapies for chronic noncancer pain. To formulate recommendations for the design of future studies, the results of their analysis were compared with established guidelines for the evaluation of medical evidence.

Evidence supporting the efficacy of neurostimulation has been collected predominantly from retrospective series or from prospective studies whose design or methods of analysis make them subject to limited interpretation. To date, there has been no successful clinical study focused on establishing the efficacy of neurostimulation for pain and incorporating sufficient numbers of participants, matched control groups, sham stimulation, randomization, prospectively defined end points, and methods for controlling experimental bias. Currently available data provide little support for the common practices of psychological or pharmacological screening or trial stimulation to predict and/or improve long-term results.

Conclusions

These findings do not diminish the value of previous investigations or positive patient experiences and do not mean that the treatments are ineffective; rather, they reveal that new data are required to answer the questions raised in and by previous study data. Future analyses of emerging neurostimulation modalities for pain should, whenever feasible, require unambiguous diagnoses as an entry criterion and should involve the use of randomization, parallel control groups that receive sham stimulation, and blinding of patients, investigators, and device programmers. Given the chronicity of patient symptoms and stimulation therapies, efficacy should be studied for 1 year or longer after device implantation. Meticulous study methods are especially important to evaluate new therapies like motor cortex and occipital nerve stimulation.
Vascular complications of vestibular schwannoma surgery: a comparison of the suboccipital retrosigmoid and translabyrinthine approaches
Authors: Sade Burak , Mohr Gérard , Dufour Jean-Jacques
Published: January 2008

Object

Vascular complications of the surgery for vestibular schwannomas (VSs) can have devastating consequences; however, there is scant literature on the systematic analysis of the different types of complications. In this context, the authors of this study analyzed these complications, with particular interest in the role of surgical approach in their occurrence.

Methods

The charts of 391 patients who had undergone 413 procedures for VS during a 24-year period were reviewed retrospectively. A suboccipital retrosigmoid (RS) approach was used in 338 procedures, and the translabyrinthine (TL) route in 75. Postoperative hemorrhage or infarction was identified and stratified according to the complication type and surgical approach.

Postoperative vascular complications were encountered in 11 procedures (2.7%), and their incidence was the same for both the RS and TL approaches. Of these complications, eight were hemorrhagic (two cerebellopontine angle, one intracerebellar, and five epidural hematomas) and three were ischemic in nature. Five patients (45.4%) had a complete recovery, and four patients (36.4%) a partial recovery; two patients (18.2%) died. The overall procedure-related mortality rate was 0.5% (two of 413 procedures): 0.3% (one of 338 procedures) for the RS approach and 1.3% (one of 75 procedures) for the TL approach (p > 0.05).

Conclusions

In this study, the overall incidences of vascular complications in VS surgery were similar for the RS and TL approaches. Regardless of the preferred surgical route, this group of complications carries a significant risk of morbidity and therefore warrants special consideration in the management of VSs.
Surgery for large vestibular schwannomas: how patients and surgeons perceive quality of life
Authors: Nicoucar Keyvan , Momjian Shahan , Vader John-Paul , de Tribolet Nicolas
Published: January 2008

Object

The aim of this study was to assess the consequences of total removal of a large vestibular schwannoma on the patient’s symptoms and quality of life (QOL).

Methods

A questionnaire regarding preoperative and postoperative symptoms with measures of both daily and global QOL and a modified 36-Item Short Form Health Survey (SF-36) QOL instrument were sent to 103 patients who had undergone surgery via a retrosigmoid approach for total removal of a Grade III or IV vestibular schwannoma. In addition, 48 patients underwent follow-up clinical examinations to assess their conditions.

Seventy-two of the 103 patients completed and returned the questionnaire. Forty-six (64%) of the schwannomas were Grade IV and 26 (36%) were Grade III. The patients’ pre- and postoperative symptoms were similar to those reported in other studies. The patients’ perceptions of facial movement were likely to be worse than the clinicians’ estimation based on the House–Brackmann classification. All scores in the QOL categories were significantly reduced when compared with normative data. Patients with large vestibular schwannomas had lower scores in all SF-36 categories except pain compared with data from other studies. Psychological problems were the preponderant symptoms, and their presence was the most powerful predictive variable for global and daily QOL.

Conclusions

Surgery for a large vestibular schwannoma has a significant impact on the patient’s QOL. To improve QOL postoperatively, the patient should be prepared and well informed of the consequences of such a surgery on QOL. Clinicians must be aware that early involvement of a clinical psychologist may be very helpful.
Gamma Knife surgery for metastatic brainstem tumors
Authors: Yen Chun Po , Sheehan Jason , Patterson Greg , Steiner Ladislau
Published: January 2008

Object

The authors review imaging and clinical outcomes in patients with metastatic brainstem tumors treated using Gamma Knife surgery (GKS).

Methods

Between March 1989 and March 2005, 53 patients (24 men and 29 women) with metastatic brainstem lesions underwent GKS. The metastatic deposits were located in the midbrain in eight patients, the pons in 42, and the medulla oblongata in three. Lung cancer was the most common primary malignancy, followed by breast cancer, melanoma, and renal cell carcinoma. The mean volume of the metastatic deposits at the time of treatment was 2.8 cm3 (range 0.05–21 cm3). The prescription doses varied from 9 to 25 Gy (mean 17.6 Gy).

Imaging follow-up studies were not completed in 16 patients, because of the short-term survival in 11 and patient refusal in five. Of the remaining 37 patients, who underwent an imaging follow-up evaluation at a mean of 9.8 months (range 1–25 months), the tumors disappeared in seven, shrank in 22, remained unchanged in three, and grew in five. All but one of 18 patients with asymptomatic brainstem deposits remained free of symptoms. In 35 patients with symptomatic brainstem deposits, neurological symptoms improved in 21, remained stable in 11, and worsened in three. At the time of this study, 10 patients were alive, and their survival ranged from 3 to 52 months after treatment. Thirty-four patients died of extracranial disease, three of the progressing metastatic brainstem lesion, and six of additional progressing intracranial deposits in other parts of the brain. The overall median survival period was 11 months after GKS. In terms of survival, the absence of active extracranial disease was the only favorable prognostic factor. Neither previous whole-brain radiation therapy nor a single brainstem metastasis was statistically related to the duration of survival.

Conclusions

Compared with allowing a metastatic brainstem lesion to take its natural course, GKS prolongs survival. The risks associated with such treatment are low. The severity of systemic diseases largely determines the prognosis of metastases to the brainstem.
Effects of balloon angioplasty on perfusion- and diffusion-weighted magnetic resonance imaging results and outcome in patients with cerebral vasospasm
Authors: Beck Jürgen , Raabe Andreas , Lanfermann Heiner , Berkefeld Joachim , De Rochemont Richard Du Mesnil , Zanella Friedhelm , Seifert Volker , Weidauer Stefan
Published: January 2008

Object

The aim of this study was to analyze the effects and outcome of transluminal balloon angioplasty (TBA) on brain tissue perfusion by using combined perfusion- and diffusion-weighted (PW/DW) magnetic resonance (MR) imaging in patients with cerebral vasospasm after subarachnoid hemorrhage.

Methods

Ten consecutive patients with cerebral vasospasm treated using TBA were included in this prospective study. Hemodynamically relevant vasospasm was diagnosed using a standardized PW/DW MR imaging protocol. Digital subtraction angiography was used to confirm vasospasm, and TBA was performed to dilate vasospastic arteries. The PW/DW imaging protocol was repeated after TBA. The evaluation of the passage of contrast medium after standardized application using the bolus tracking method allowed for the calculation of the time to peak (TTP) before and after TBA.

Tissue at risk was defined based on perfusion delays in individual vessel territories compared with those in reference territories. In cases with proximal focal vasospasm, TBA could dilate spastic arteries. Follow-up PW/DW MR imaging showed the disappearance of, or a decrease in, the mismatch. A TBA-induced reduction in the perfusion delay of 6.2 ± 1 seconds (mean ± standard error of the mean) to 1.5 ± 0.45 seconds resulted in the complete prevention of infarction; a reduction in the delay of 6.2 ± 2.7 to 4.1 ± 1.9 seconds resulted in the preservation of those brain tissue parts having only small infarcts in the vessel territories. Without TBA, however, the perfusion delay remained or even increased (11.1 ± 3.7 seconds), and the complete infarction of a territory occurred.

Conclusions

Angioplasty of vasospastic arteries leads to hemodynamic effects that can be quantified using PW/DW MR imaging. In cases of a severe PW/DW imaging mismatch successful TBA improved tissue perfusion and prevented cerebral infarction. The clinical significance of PW/DW MR imaging and the concept of tissue at risk is shown by cerebral infarction in vessels not accessible by TBA.
Primary stent therapy for symptomatic intracranial atherosclerotic stenosis: 1-year follow-up angiographic and midterm clinical outcomes
Authors: Lee Chang-Young , Yim Man-Bin
Published: January 2008

Object

The aim of this study was to report 1-year angiographic follow-up results and midterm clinical outcomes in patients with symptomatic intracranial atherosclerotic lesions treated with stent placement.

Methods

Ten patients with ischemic symptoms referable to stenotic intracranial atherosclerotic arteries, with greater than 60% stenosis, underwent elective surgery in which a primary stent was placed. All patients underwent pretreatment (≥ 1 week) combination oral antiplatelet (clopidogrel and aspirin) therapy and long-term (6-month) combination oral antiplatelet (clopidogrel and aspirin) therapy after stents were placed. The procedure involved selecting stents of the same size as the diameter of the target vessel and slowly inflating the balloon to its nominal pressure. One-year angiography and midterm clinical follow-up data were obtained.

The stents were successfully placed in all patients without any perioperative complication. The mean preoperative stenosis rate of 81% decreased to 4% after the stent was placed. Nine patients who underwent follow-up angiography (one patient refused) at a mean of 12.3 months (range 10–19 months) had no changes in luminal diameter compared with the immediate postoperative luminal diameter. Luminal narrowing increased, from 15 to 38%, in one case in which there was comparatively greater residual stenosis (15%). No patient suffered new ischemic symptoms during a mean clinical follow-up period of 21 months (range 12–36 months).

Conclusions

Elective stent surgery can provide good angiographic and clinical midterm outcomes in patients with symptomatic intracranial atherosclerotic stenosis, and the procedure is associated with a high degree of technical success. Reassessment of these promising results is needed in a larger population and in a randomized prospective comparison study.