bluuebunny/crossref_metadata_2025 huggingface dataset:
Myofibroblastoma in the suprasellar region
Authors: Shinojima Naoki , Ohta Kazutaka , Yano Shigetoshi , Nakamura Hideo , Kochi Masato , Ishimaru Yasuji , Nakazato Youichi , Ushio Yukitaka
Published: May 2009

✓ Myofibroblastoma is a rare type of benign mesenchymal tumor; only two cases of intracranial myofibroblastoma have been reported in the literature. The authors report on the case of a 34-year-old woman with a myofibroblastoma in the suprasellar region who presented with the complaint of sudden onset of headache followed within 2 weeks by progressively worsening visual disturbance. Computerized tomography scanning demonstrated a mixed low- and high-density mass in the suprasellar region and contrast-enhanced magnetic resonance imaging revealed the mass to be of mixed intensity with heterogeneous enhancement. The tumor was subtotally removed via a right frontobasal translamina—terminalis approach and her vision improved immediately. Histologically, the tumor was characterized by alternating areas of spindle-shaped and round cells that were separated by collagen fibers. The diagnosis of myofibroblastoma was based on the tumor's intense immunoreactivity for α—smooth-muscle actin and the ultrastructural identification of myofibroblasts. The tumor was thought to have originated from the meninges in the suprasellar region.
Extradural motor cortex stimulation for advanced Parkinson disease
Authors: Canavero Sergio , Paolotti Riccardo , Bonicalzi Vincenzo , Castellano Giancarlo , Greco-Crasto Stefania , Rizzo Laura , Davini Ottavio , Zenga Francesco , Ragazzi Paola
Published: May 2009

✓ Motor cortex stimulation is a minimally invasive surgical procedure used for pain control. The authors report their results treating two patients with typical Parkinson disease. Unilateral motor cortex stimulation proved to be beneficial bilaterally. Motor cortex stimulation may represent a cost-effective alternative to deep brain stimulation.
Endoscopic endonasal treatment of a spontaneous temporosphenoidal encephalocele with a detachable silicone balloon
Authors: Alfieri Alessandra , Schettino Raffaele , Taborelli Angelo , Pontiggia Maurizio , Reganati Paolo , Ballarini Valerio , Monolo Luigi
Published: May 2009

✓ Temporosphenoidal encephaloceles are rare entities that occur when the temporal lobe herniates into the sphenoid sinus through a skull base defect of the temporal bone. Both an iatrogenic and a traumatic pathogenesis have been proposed.

The authors describe a spontaneously occurring temporosphenoidal encephalocele in a 63-year-old woman who had a 4-year history of rhinorrhea. Spiral computerized tomography (CT) scanning revealed a bone defect located inside the ophthalmomaxillary triangle. The intrasphenoidal encephalocele had a heterogeneously hypointense signal compared with cerebrospinal fluid (CSF) on T1-weighted magnetic resonance (MR) images and a hyperintense signal compared with CSF on T2-weighted MR images. Two previous endonasal endoscopic procedures, performed by ear, nose, and throat surgeons, had been unsuccessful. The authors performed an endoscopic endonasal right nostril procedure by using 0° and 45° rigid-lens endoscopes that were 4 mm in diameter and 18 cm long. The encephalocele in the sphenoid sinus was partially removed. DuraGen and fat graft were positioned in the bone defect. Two No. 2 French detachable silicone balloons (1.5 cm3 volume) inflated with surgical glue were introduced into the skull defect and into the sphenoid sinus, respectively. The CSF leakage stopped immediately. No nasal packing or postoperative CSF lumbar drainage was necessary. The patient did well. Postoperative CT and MR imaging, obtained at 24 hours and at 3 months, demonstrated that the balloon and the fat graft filled the bone defect and the sphenoid sinus. Eight months postprocedure no CSF leakage was observed. This appears to be the first case reported in the literature of a temporosphenoidal encephalocele successfully treated by an endoscopic endonasal technique involving packing of the defect with inflated detachable balloons.
Intracranial aneurysms associated with unsuspected aortic coarctation
Authors: Mercado Rodrigo , López Susana , Cantú Carlos , Sanchez Angel , Revuelta Rogelio , Gómez-Llata Sergio , Bouffard J. Antonio , Pineda Carlos
Published: May 2009

✓ Intracranial aneurysms (IAs) are found more often in patients with aortic coarctation (AC) than in the general population and aneurysm rupture occurs much earlier in the lives of these patients when there is coexistent AC. The diagnosis of AC is frequently made only after a serious cerebrovascular complication has developed. The aim of this paper is to call attention to AC in patients presenting with aneurysmal subarachnoid hemorrhage. The literature is reviewed, the key clinical features are highlighted, and the proposed pathogenesis of this association is discussed.

The authors present clinical information and imaging data obtained in three young patients with ruptured IAs that were associated with initially unnoticed AC. Abnormal results of cardiovascular examinations led the authors to consider an underlying AC, which was later confirmed by aortography. These aneurysms were successfully treated prior to correction of the ACs.

The diagnosis of AC should be considered in adolescent and young adult patients presenting with IAs.
Brachial plexopathy due to chondrolipoangioma
Authors: Sekula Raymond F. , Oh Michael Y. , Bellotte J. Brad , Wilberger Jack E.
Published: May 2009

✓ Chondrolipoangioma is a mesenchymoma primarily composed of cartilage, with adipose tissue and vascular elements present in lesser proportions. Chondrolipoangiomas have been reported to occur in the extremities, chest wall, oral soft tissues, mediastinum, uterus and its round ligament, seminal vesicles, and heart. In this report, the authors present an unusual case in which a chondrolipoangioma caused a brachial plexopathy. To their knowledge, a chondrolipoangioma has never been reported in the neurosurgical literature.
Downregulation of cerebrospinal fluid production in patients with chronic hydrocephalus
Authors: Silverberg Gerald D. , Huhn Stephen , Jaffe Richard A. , Chang Steven D. , Saul Thomas , Heit Gary , Von Essen Ann , Rubenstein Edward
Published: May 2009

Object. The goal of this study was to determine the effect of hydrocephalus on cerebrospinal fluid (CSF) production rates in patients with acute and chronic hydrocephalus.

Methods. The authors studied CSF production both in patients presenting with acute and chronic hydrocephalus, and patients with Parkinson disease (PD) of a similar mean age, whose CSF production was known to be normal. A modification of the Masserman method was used to measure CSF production through a ventricular catheter. The CSF production rates (means ± standard deviations) in the three groups were then compared.

The patients with PD had a mean CSF production rate of 0.42 ± 0.13 ml/minute; this value lies within the normal range measured using this technique. Patients with acute hydrocephalus had a similar CSF production rate of 0.4 ± 0.13 ml/minute, whereas patients with chronic hydrocephalus had a significantly decreased mean CSF production rate of 0.25 ± 0.08 ml/minute.

Conclusions. The authors postulate that chronic increased intracranial pressure causes downregulation of CSF production.
Increased levels of lipid peroxides as predictive of symptomatic vasospasm and poor outcome after aneurysmal subarachnoid hemorrhage
Authors: Kamezaki Takao , Yanaka Kiyoyuki , Nagase Sohji , Fujita Keishi , Kato Noriyuki , Nose Tadao
Published: May 2009

Object. Cerebral vasospasm remains a devastating medical complication of aneurysmal subarachnoid hemorrhage (SAH). Reactive oxygen species and subsequent lipid peroxidation are reported to participate in the causes of cerebral vasospasm. This clinical study was performed to investigate the relationships between levels of lipid peroxides in cerebrospinal fluid (CSF) and both delayed cerebral vasospasm and clinical outcome after SAH.

Methods. Levels of phosphatidylcholine hydroperoxide (PCOOH) and cholesteryl ester hydroperoxide (CEOOH) in the CSF were measured in 20 patients with aneurysmal SAH. The patients' CSF was collected within 48 hours of hemorrhage onset and on Day 6 or 7 post-SAH. On Day 7, angiography was performed to verify the degree and extent of the vasospasm. The relationship between the patients' clinical profiles and the levels of lipid peroxides in the CSF were investigated.

Both PCOOH and CEOOH were detectable in CSF, and their levels decreased within 7 days after onset of SAH. The levels of CEOOH within 48 hours after onset of hemorrhage were significantly higher in patients in whom symptomatic vasospasm later developed than in patients in whom symptomatic vasospasm did not develop (p = 0.002). Levels of PCOOH measured within 48 hours after onset of hemorrhage were significantly higher in patients with poor outcomes than in patients with good outcomes (p = 0.043).

Conclusions. Increased levels of lipid peroxides measured in the CSF during the acute stage of SAH were predictive of both symptomatic vasospasm and poor outcome. Measurements of lipid peroxides in the CSF may be useful prognostically for patient outcomes as well as for predicting symptomatic vasospasm.
New laboratory model for neurosurgical training that simulates live surgery
Authors: Aboud Emad , Al-Mefty Ossama , Yaşargil M. Gazi
Published: May 2009

Object. Laboratory training models are essential for developing and refining surgical skills, especially for microsurgery. The closer to live surgery the model is, the greater the benefit. In this paper the authors introduce a cadaver model with unique characteristics: dynamic filling of the cerebral vasculature with colored liquid and clear fluid filling of the arachnoid cisterns. This model is distinctive and has great practical value for training in a wide range of surgical procedures.

Methods. Cadaveric heads were prepared for surgical procedures in the following manner: the carotid arteries (CAs) and vertebral arteries (VAs) in the neck were cannulated, as were the internal jugular veins (JVs) on both sides. Two tubes were introduced into the spinal canal and each one was advanced into one of the cerebellopontine angle cisterns. A CA, VA, or both were then connected to a reservoir containing light red fluid and a pressure of 80 to 120 mm Hg and a pulse rate of 60 beats/minute were established using a pump. The JV on the side currently being dissected was connected to a reservoir containing dark red fluid and kept at a pressure between 20 and 40 mm Hg. The remaining vessels were clamped in the neck. The cisternal tubes were connected to a reservoir of clear fluid that was regulated by an adjustable flow. Nine trainees have tested this model on eight specimens by practicing a variety of surgical procedures and maneuvers, including craniotomies; hemostasis; cisternal and vascular dissection; vascular anastomosis and repair; establishment of arterial bypasses; aneurysm creation, dissection, and clipping; management of an aneurysm rupture; intraparenchymal resection such as amygdalohippocampectomy; ventricular endoscopy and third ventriculostomy; cavernous sinus and skull base approaches; and resection of artificial tumors in the basal cisterns.

Conclusions. This model mimics the normal human anatomy and dynamic vascular filling found in real surgery and presents it from the training perspective, allowing a wide range of skill development and repeated practice. It provides an alternative model to laboratory animals. It is inexpensive and readily available, and has great value for the acquisition and refinement of surgical skills that are not only specific to neurosurgery, but are applicable to other surgical disciplines.
Analysis of immunoglobulin H gene rearrangement by polymerase chain reaction in primary central nervous system lymphoma
Authors: Kros Johan M. , Bagdi Eniko K. , Zheng Pingpin , Hop Wim C. , Driesse Maarten J. , Krenacs Laszlo , Dinjens Winand N. M.
Published: May 2009

Object. Diagnosing primary central nervous system lymphoma (PCNSL) may be difficult either because of a paucity of tumor cells in the brain biopsy specimens or a failure to demonstrate monoclonality on immunomorphological studies. Monoclonality can also be demonstrated by amplification of the rearranged immunoglobulin H genes by polymerase chain reaction (PCR) to the framework region (FR)3 and FR2 complementarity determining region (CDR)-III and CDR-II of these genes. The PCR method is feasible with formalin-fixed, paraffin-embedded biopsy material and has proven to be helpful in the diagnosis of non-Hodgkin lymphoma on biopsy samples obtained from various locations in the body. Nevertheless, few studies have addressed the value of this method in the context of PCNSL. In the present study, the contribution of both FR3 single and FR2 seminested PCR procedures for confirming the diagnosis of PCNSL was estimated retrospectively in 30 cases of PCNSL and in three cases of epidural lymphoma.

Methods. Twenty-eight cases of immunophenotypically confirmed PCNSL and two of suspected lymphoma were studied. Tissue specimens obtained in 22 cases of other cerebral diseases, among which were various inflammatory conditions, were used as negative controls. In 18 (60%) of 30 cases the results of FR3 PCR demonstrated monoclonality, whereas FR2 PCR showed monoclonality in 12 cases (40%). In 11 cases FR3 PCR yielded monoclonal patterns and FR2 PCR did not, whereas reversibly in five cases FR2 PCR proved monoclonality and FR3 PCR failed to do so. Adding the results of FR3 to those of FR2 PCR, monoclonal patterns were obtained in 23 (77%) of 30 cases. In both cases in which lymphoma was suspected but not proven immunomorphologically, FR3 PCR revealed monoclonality, as did FR2 PCR in one case. In all 22 control lesions either polyclonal patterns were seen or no consistent patterns were obtained. In the PCNSL group, older age of patients and multifocal presentation of lesions on neuroimaging were significantly associated with worse survival. No correlation between histological subtype and clinical outcome was elucidated.

Conclusions. The application of FR3 and FR2 PCR is a useful additional tool in making the diagnosis of PCNSL. Moreover, in some cases the PCR method may be essential in distinguishing neoplasia from reactive conditions.
A new reproducible model of an epidural mass lesion in rodents. Part I: Characterization by neurophysiological monitoring, magnetic resonance imaging, and histopathological analysis
Authors: Burger Ralf , Bendszus Martin , Vince Giles Hamilton , Roosen Klaus , Marmarou Anthony
Published: May 2009

Object. The goal of this study was to characterize a new model of an epidural mass lesion in rodents by means of neurophysiological monitoring, magnetic resonance imaging, and histopathological analysis.

Methods. Changes in intracranial pressure (ICP), cerebral perfusion pressure (CPP), and laser Doppler flowmetry (LDF) values, intraparenchymal tissue partial oxygen pressure (PtiO2), and electroencephalography (EEG) activity were evaluated in the rat during controlled, epidural expansion of a latex balloon up to a maximum ICP of 60 mm Hg. The initial balloon inflation was followed by periods of sustained inflation (30 ± 1 minute) and reperfusion (180 ± 5 minutes). Histopathological analysis and magnetic resonance (MR) imaging were performed to characterize the lesion.

The time to maximum balloon expansion and the average balloon volume were highly reproducible. Alterations in EEG activity during inflation first appeared when the CPP decreased to 57 mm Hg, the LDF value to 66% of baseline values, and the PtiO2 to 12 mm Hg. During maximum compression, the CPP was reduced to 34 mm Hg, the LDF value to 40% of baseline, and the PtiO2 to 4 to 5 mm Hg. The EEG tracing was isoelectric during prolonged inflation and the values of LDF and PtiO2 decreased due to accompanying hypotonia. After reperfusion, the CPP was significantly decreased (p < 0.05) due to the elevation of ICP. Both the LDF value and EEG activity displayed incomplete restoration, whereas the value of PtiO2 returned to normal. Histological analysis and MR imaging revealed brain swelling with a midline shift and a combined cortical—subcortical ischemic lesion beyond the site of balloon compression.

Conclusions. This novel model of an epidural mass lesion in rodents closely resembles the process observed in humans. Evaluation of pathophysiological and morphological changes was feasible by using neurophysiological monitoring and MR imaging.
Hajdu—Cheney syndrome and syringomyelia
Authors: Faure Alexis , David Albert , Moussally Frédéric , Khalfallah Mansour , Jacquemont Sébastien , Hamel Olivier , Conti Michele , Hamel Antoine , Raoul Sylvie , Robert Roger
Published: May 2009

✓ This 7-year-old boy with Hajdu—Cheney syndrome presented with cervical syringomyelia related to rapidly progressing platybasia. Decompressive craniectomy provided temporary improvement, and his clinical status was eventually stabilized after external immobilization, according to findings at 2.5 years of follow up. In a review of the literature the authors found 57 cases of the syndrome, only three of which were associated with syringomyelia. The youth of the patient, the severe form and rapid course of the disease, and the very specific anatomical conditions related to cranial and facial deformities raised various therapeutic problems.
Rotational vertebral artery occlusion from occipital bone anomaly: a rare cause of embolic stroke
Authors: Tominaga Teiji , Takahashi Toshiyuki , Shimizu Hiroaki , Yoshimoto Takashi
Published: May 2009

✓ Vertebral artery (VA) occlusion by rotation of the head is uncommon, but can result from mechanical compression of the artery, trauma, or atlantoaxial instability. Occipital bone anomalies rarely cause rotational VA occlusion, and patients with nontraumatic intermittent occlusion of the VA usually present with compromised vertebrobasilar flow.

A 34-year-old man suffered three embolic strokes in the vertebrobasilar system within 2 months. Magnetic resonance imaging demonstrated multiple infarcts in the vertebrobasilar territory. Angiography performed immediately after the third attack displayed an embolus in the right posterior cerebral artery. Radiographic and three-dimensional computerized tomography bone images exhibited an anomalous osseous process of the occipital bone projecting to the posterior arch of the atlas. Dynamic angiography indicated complete occlusion of the left VA between the osseous process and the posterior arch while the patient's head was turned to the right. Surgical decompression of the VA resulted in complete resolution of rotational occlusion of the artery.

An occipital bone anomaly can cause rotational VA occlusion at the craniovertebral junction in patients who present with repeated embolic strokes resulting from injury to the arterial wall.
Intention-to-treat analysis of Spetzler—Martin Grades IV and V arteriovenous malformations: natural history and treatment paradigm
Authors: Han Patrick P. , Ponce Francisco A. , Spetzler Robert F.
Published: May 2009

Object. In this study the authors quantified a subgroup of patients with Spetzler—Martin Grades IV and V arteriovenous malformations (AVMs) recommended for complete, partial, or no treatment, and calculated the retrospective hemorrhage rate for these lesions.

Methods. Between July 1997 and May 2000, 73 consecutive patients with Grades IV and V AVMs were evaluated prospectively by the cerebrovascular team at Barrow Neurological Institute. Treatment recommendations given to the patients or referring physicians were classified as complete treatment, partial treatment, and no treatment. Retrospectively, the hemorrhage rates associated with these treatment groups were also calculated.

In the prospective portion of the study (the intention-to-treat analysis), no treatment of the AVM, was recommended for 55 patients (75%) and partial treatment was recommended for seven patients (10%). Aneurysms associated with an AVM were obliterated by surgical or endovascular treatment in seven patients (10%), and complete surgical removal was recommended for four patients (5%). The overall hemorrhage rate for Grades IV and V AVMs was 1.5% per year. The annual risk of hemorrhage was 10.4% among patients who previously had received incomplete treatment, compared with patients without previous treatment.

Conclusions. The hemorrhage risk of 1.5% per year, which was associated with Grades IV and V AVMs appears to be lower than that reported for Grades I through III AVMs. The authors recommend that no treatment be given for most Grades IV and V AVMs. No evidence indicates that partial treatment of an AVM reduces a patient's risk of hemorrhage. In fact, partial treatment may worsen the natural history of an AVM. The authors do not support palliative treatment of AVMs, except in the specific circumstances of arterial or intranidal aneurysms or progressive neurological deficits related to vascular steal. Complete treatment is warranted for patients with progressive neurological deficits caused by hemorrhage of the AVM. This selection process plays a significant role in the relatively low combined morbidity and mortality rates for Grade IV and Grade V AVMs (17 and 22%, respectively) reported by the cerebrovascular group in both retrospective and prospective studies.
Preoperative and postoperative cognitive functioning in patients with frontal meningiomas
Authors: Tucha Oliver , Smely Christian , Preier Michael , Becker Georg , Paul Geraldine M. , Lange Klaus W.
Published: May 2009

Object. There is presently no specific information available concerning the nature and course of cognitive deficits caused by intracranial meningiomas. In this prospective study the authors examined the cognitive functioning of patients with frontal meningiomas.

Methods. Fifty-four patients with frontal meningiomas were examined neuropsychologically before and after neurosurgery. The test battery consisted of standardized instruments including those assessing memory, attention, visuoconstructive abilities, and executive functions. The time period between pre-and postoperative assessment ranged from 4 to 9 months. The patients' performance was compared with the results in 54 healthy adults who were also assessed twice by using the same test battery in a period ranging from 4 to 9 months. In addition, the effect on cognition of meningioma lateralization, localization, lesion size, edema, brain compression, time course, and the occurrence of preoperative seizures was analyzed.

Conclusions. Except in the case of working memory, comparisons of pre- and postoperative assessments of cognition revealed no differences in memory, visuoconstructive abilities, or executive functions, although a postoperative improvement in attentional functions was observed. The results of this study indicate that the surgical removal of frontal meningiomas does not impair patients' cognitive functioning. Furthermore, improvements in attentional functions may occur in these patients.
The impact of stereotactic pallidal surgery on the dopamine D2 receptor in Parkinson disease: a positron emission tomography study
Authors: Nakajima Takeshi , Nimura Taro , Yamaguchi Keiichiro , Ando Tadashi , Itoh Masatoshi , Yoshimoto Takashi , Shirane Reizo
Published: May 2009

Object. The aim of this study was to estimate the impact of stereotactic pallidal surgery on the binding potential of dopamine D2 receptors in patients with advanced Parkinson disease (PD).

Methods. Six patients with advanced PD (three men and three women; mean age 56.7 ± 9.8 years, Hoehn and Yahr stage 3.3 ± 1.1/3.9 ± 1.2 [on/off scores], mean ± standard deviation) underwent stereotactic pallidal surgery. One underwent right posteroventral pallidotomy (PVP), one received left PVP, three were treated with deep brain stimulation (DBS) of the left globus pallidus internus (GPi), and one with bilateral DBS of the GPi. The binding potential of the dopamine D2 receptors of these patients was determined before and after surgery by using positron emission tomography scanning with 11C-nemonapride and it was compared with the value in eight healthy volunteers. The authors also examined whether changes in the D2 receptor binding potential were correlated with the clinical outcome. The clinical symptoms, especially those in the off state, were significantly improved after surgery. Preoperatively, the D2 receptor binding potential in the putamen was elevated by 27% (p < 0.01) and that in the thalamus was 29% lower than that in controls (p < 0.01). The D2 receptor binding potential in the putamen and thalamus returned to control levels after surgery. The preoperative level of the D2 receptor binding potential in the anterior cingulate cortex was comparable to that of controls, but it declined significantly after surgery, whereas the D2 receptor binding potential in other regions of both hemispheres showed no significant changes after surgery. Although the D2 receptor binding potential did not correlate with the Hoehn and Yahr stage, the Schwab and England score, or the Unified PD Rating Scale (UPDRS) score, a positive correlation was seen between the percent improvement rate of the total UPDRS score in the off state and the percentage change of the D2 receptor binding potential in the putamen (r = 0.773, p = 0.0417 according to the Pearson linear correlation).

Conclusions. The altered dopamine D2 receptor binding potential in the putamen might play a crucial role in clinical improvement after PVP or DBS of the GPi in advanced PD.
Surgical management of brainstem hemangioblastomas in patients with von Hippel—Lindau disease
Authors: Weil Robert J. , Lonser Russell R. , Devroom Hetty L. , Wanebo John E. , Oldfield Edward H.
Published: May 2009

Object. Hemangioblastomas of the brainstem constitute 5 to 10% of central nervous system (CNS) tumors in patients with von Hippel—Lindau (VHL) disease. At present, optimal management of brainstem hemangioblastomas associated with VHL disease is incompletely defined. In an attempt to clarify some of the uncertainty about the operative treatment of these lesions and its outcome, the authors reviewed all cases of VHL disease in which resection of brainstem hemangioblastomas was performed at the National Institutes of Health during a 10-year period.

Methods. Twelve consecutive patients with VHL disease (six male and six female patients [mean age 31.7 ± 9 years; range 15–46 years]) who underwent 13 operations to remove 17 brainstem hemangioblastomas were included in this study (mean follow-up period, 88.4 ± 37.4 months; range 37–144 months). Serial examinations, hospital charts, magnetic resonance images, and operative records were reviewed. To evaluate clinical course, clinical grades were assigned to each patient before and after surgery.

Preoperative neurological function was the best predictor of long-term outcome. In addition, patients who underwent CNS surgeries for hemangioblastomas were more likely to improve or to remain neurologically stable. Tumor or cyst size, the presence of a cyst, or the location of the tumor (intramedullary, extramedullary, or mixed; posterior medullary, obex, or lateral) did not affect outcome. No patient was neurologically worse after brainstem surgery. At long-term follow-up review (mean 88.4 months), only one patient had declined neurologically and this was due to the cumulative neurological effects caused by eight additional hemangioblastomas of the spinal cord and their surgical treatment.

Conclusions. Brainstem hemangioblastomas in patients with VHL disease can be removed safely; they generally should be resected when they become symptomatic or when the tumor has reached a size such that further growth will increase the risks associated with surgery, or in the presence of an enlarging cyst. Magnetic resonance imaging is usually sufficient for preoperative evaluation and presurgical embolization is unnecessary. The goal of surgery is complete resection of the lesion before the patient experiences a disabling neurological deficit.
Progressive and extensive dopaminergic degeneration induced by convection-enhanced delivery of 6-hydroxydopamine into the rat striatum: a novel rodent model of Parkinson disease
Authors: Oiwa Yoshitsugu , Sanchez-Pernaute Rosario , Harvey-White Judith , Bankiewicz Krys S.
Published: May 2009

Object. A striatal dopamine lesion induces progressive nigral degeneration in rodents; however, intrastriatal injection of 6-hydroxydopamine (6-OHDA) causes only limited lesions due to spontaneous regeneration of the neurons that survive. To make an extensive lesion, the authors used a convection-enhanced delivery (CED) method for intrastriatal infusion of 6-OHDA and evaluated the animals for a model of Parkinson disease (PD).

Methods. Different doses of 6-OHDA were infused into the unilateral striatum in rats by using the CED method. The dopaminergic neuronal degeneration was evaluated based on morphological, biochemical, and behavioral measurements until 8 weeks postlesion.

Due to the wide distribution of the drug, CED of 20 µg of 6-OHDA into the striatum was sufficient to obtain a progressive and extensive nigrostriatal lesion as defined by morphological (> 80% cell loss in the substantia nigra [SN]) and biochemical (> 95% decrease in striatal dopamine) criteria. The extent of the lesion manifested as a stable turning behavior with amphetamine (> 6 turns/minute) and apomorphine (> 4 turns/minute). It also appeared that at 1 week postlesion the apoptotic markers were maximal in neurons of the SN.

Conclusions. A rat model of PD with a progressive and extensive dopamine lesion was successfully made by intrastriatal CED of 6-OHDA. In this model, the therapeutic value can be assessed using behavioral, biochemical, and histochemical measurements. The delay of nigral neuronal death with respect to the time of 6-OHDA administration may provide a therapeutic window for testing neuroprotective strategies.
Growth inhibition of human malignant glioma cells induced by the PI3-K—specific inhibitor
Authors: Shingu Takashi , Yamada Kazuo , Hara Nobumasa , Moritake Kouzo , Osago Harumi , Terashima Masaharu , Uemura Takeshi , Yamasaki Toshiki , Tsuchiya Mikako
Published: May 2009

Object. The phosphatase and tensin homolog deleted from chromosome 10 (PTEN) functions as a tumor suppressor by negatively regulating the growth/survival signals of the phosphatidylinositol 3-kinase (PI3-K)/Akt pathway. The PI3-K/Akt pathway in PTEN-deficient tumors may be one of the key targets for anticancer therapy. The authors examined the effects of the PI3-K inhibitor 2-(4-morpholinyl)-8-phenylchromone (LY294002) on human malignant glioma cells, and compared these effects on PTEN-deficient cells with those on PTEN—wild-type (PTEN-wt) cells.

Methods. Using human malignant glioma cell lines, including the PTEN-deficient cells A172 and U87MG and the PTEN-wt cells LN18 and LN229, the effects of LY294002 on cell growth, apoptosis, and chemotherapeutic agent—induced cytotoxicity were evaluated. The LY294002 inhibited the growth of U87MG cells associated with reduced phosphatidylinositol 3,4,5,-trisphosphate and phosphorylated Akt, and also induced growth inhibition in three other cell lines. Although LY294002 caused apoptosis in all four cell lines, apoptosis seemed to contribute to only a small portion of growth inhibition induced by LY294002. There was no link between the status of PTEN and the median inhibitory concentration values for LY294002 or between the gene status and the extent of LY294002-induced apoptosis. The LY294002 significantly augmented the cytotoxicity induced by etoposide in PTEN-deficient cells, but not in PTEN-wt cells. Enhancement of 1,3-bis(2-chloroethyl)-1-nitrosourea— and cisplatin-induced cytotoxicity by LY294002 was not linked to the status of PTEN. No marked difference in the amounts of phosphorylated Akt was found between PTEN-deficient and PTEN-wt cells.

Conclusions. The findings show that PI3-K is a possible target for therapy in patients with gliomas, and PI3-K inhibitors in combination with chemotherapeutic agents could be potent therapeutic modalities for patients with malignant gliomas.
Comparative genomic hybridization analysis of craniopharyngiomas
Authors: Rienstein Shlomit , Adams Eric F. , Pilzer David , Goldring Ayala Aviram , Goldman Boleslaw , Friedman Eitan
Published: May 2009

Object. Craniopharyngioma is the most common childhood brain tumor and is thought to arise from embryonic remnants of the Rathke pouch. Some craniopharyngiomas are monoclonal in origin and hence presumably harbor somatic genetic alterations, although the precise molecular mechanisms involved in craniopharyngioma development are unknown. The goal of this study was to identify genetic alterations in craniopharyngiomas.

Methods. To gain insight into the molecular mechanisms involved in development of these tumors, the authors analyzed nine adamantinomatous craniopharyngiomas by using comparative genomic hybridization. Six tumors (67%) displayed at least one genomic alteration, and three had six or more alterations. Only two tumors displayed a decrease in DNA copy number, and in all others an increase in DNA copy number was noted.

Conclusions. The authors conclude that a subset of craniopharyngiomas consists of monoclonal tumors arising from activation of oncogenes located at specific chromosomal loci.
Motor cortex stimulation in a patient with intractable complex regional pain syndrome Type II with hemibody involvement
Authors: Son Byung Chul , Kim Moon Chan , Moon Dong Eon , Kang Joon Ki
Published: May 2009

✓ The authors describe the effectiveness of motor cortex stimulation (MCS) in a patient with complex regional pain syndrome (CRPS) Type II, formerly known as causalgia, with hemibody allodynia. During MCS, a subjective sensation of warm paresthesia developed in the painful hand and forearm and spread toward the trunk. Pain and allodynia in the areas associated with this sensation were alleviated significantly. The analgesic effect of stimulation proved to be long lasting and was still present at the 12-month follow up.

The authors speculate that MCS might exert its effect through the modulation of thalamic activity in this particular case of CRPS with hemisensory deficit. A central mechanism associated with functional disturbance in noxious-event processing in the thalamus might have an important role in the pathogenesis of the condition.
Apoplectic lymphocytic hypophysitis
Authors: Lee Michael S. , Pless Misha
Published: May 2009

✓ Pituitary apoplexy has not been reported in the setting of lymphocytic hypophysitis. The authors present the case of a woman with sudden vision loss and headache. Magnetic resonance imaging revealed focal hemorrhages in a sellar lesion with suprasellar extension. The results of histopathological analysis were consistent with lymphocytic hypophysitis.
Histopathological findings in a human carotid artery after stent implantation
Authors: Toma Naoki , Matsushima Satoshi , Murao Kenichi , Kawaguchi Kenji , Imanaka-Yoshida Kyoko , Yoshida Toshimichi , Taki Waro
Published: May 2009

✓ Despite the high technical success rates and the acceptable morbidity and mortality rates that are associated with carotid artery (CA) stent implantation, morphological changes in the vessel wall after this procedure are still unknown. The authors describe histopathological findings of the CA after stent implantation in a human autopsy specimen.

A 75-year-old man with asymptomatic CA stenosis underwent successful CA stent implantation, but died 8 months afterward of complications surrounding treatment of a thoracic aortic artery aneurysm. The stented CA was isolated from the autopsy specimen and was analyzed macroscopically and with the aid of scanning electron microscopy and histopathological methods.

Although there was focal persistence of a chronic inflammatory reaction around the stent struts, a stabilized neointima overlying the stent, which was principally composed of cells that stained positively for α—smooth muscle actin and collagen deposition with complete reendothelialization of the luminal surface, was confirmed in the internal CA. In contrast, residual mural thrombus around the stent struts in the common CA led to a concern about the potential risk for distal embolism in the future. The present case provides supportive evidence of stabilized neointima overlying the stent and valuable information regarding morphological characteristics useful for selecting a stent of an appropriate size.
Quantitative pupillometry, a new technology: normative data and preliminary observations in patients with acute head injury
Authors: Taylor William R. , Chen Jeff W. , Meltzer Hal , Gennarelli Thomas A. , Kelbch Cynthia , Knowlton Sharen , Richardson Jenny , Lutch Matthew J. , Farin Azadeh , Hults Kathryn N. , Marshall Lawrence F.
Published: May 2009

✓ The authors prospectively used a new hand-held point-and-shoot pupillometer to assess pupillary function quantitatively. Repetitive measurements were initially made in more than 300 healthy volunteers ranging in age from 1 to 87 years, providing a total of 2432 paired (alternative right eye, left eye) measurements under varying light conditions. The authors studied 17 patients undergoing a variety of nonintracranial, nonophthalmological, endoscopic, or surgical procedures and 20 seniors in a cardiology clinic to learn more about the effects of a variety of drugs. Additionally, the authors carried out detailed studies in 26 adults with acute severe head injury in whom intracranial pressure (ICP) was continuously monitored. Finally, five patients suffering from subarachnoid hemorrhage were also studied.

Quantitative pupillary measurements could be reliably replicated in the study participants. In healthy volunteers the resting pupillary aperture averaged 4.1 mm and the minimal aperture after stimulation was 2.7 mm, resulting in a 34% change in pupil size. Constriction velocity averaged 1.48 ± 0.33 mm/second. Pupillary symmetry was striking in both healthy volunteers and patients without intracranial or uncorrected visual acuity disorders. In the 2432 paired measurements in healthy volunteers, constriction velocity was noted to fall below 0.85 mm/second on only 33 occasions and below 0.6 mm/second on eight occasions (< one in 310 observations).

In outpatients, the reduction in constriction velocity was observed when either oral or intravenous narcotic agents and diazepam analogs were administered. These effects were transient and always symmetrical.

Among the 26 patients with head injuries, eight were found to have elevations of ICP above 20 mm Hg and pupillary dynamics in each of these patients remained normal. In 13 patients with a midline shift greater than 3 mm, elevations of ICP above 20 mm Hg, when present for 15 minutes, were frequently associated with a reduction in constriction velocity on the side of the mass effect to below 0.6 mm/second (51% of 156 paired observations). In five patients with diffuse brain swelling but no midline shift, a reduction in constriction velocities did not generally occur until the ICP exceeded 30 mm Hg. Changes in the percentage of reduction from the resting state following stimulation were always greater than 10%, even in patients receiving large doses of morphine and propofol in whom the ICP was lower than 20 mm Hg. Asymmetry of pupillary size greater than 0.5 mm was observed infrequently (< 1%) in healthy volunteers and was rarely seen in head-injured patients unless the ICP exceeded 20 mm Hg. Pupillometry is a reliable technology capable of providing repetitive data on quantitative pupillary function in states of health and disease.
Noninvasive intracranial compliance monitoring
Authors: Lang Erhard W. , Paulat Klaus , Witte Christoph , Zolondz Jürgen , Mehdorn H. Maximilian
Published: May 2009

✓ Although invasive measurement of intracranial pressure (ICP) involving high-resolution waveform analysis allows assessment of intracranial compliance (ICC), it is only feasible in a few selected neurosurgical conditions. Intracranial compliance can be assessed using the high-frequency centroid (HFC), which is the power-weighted mean frequency within the 4 to 15—Hz band of the ICP waveform. The authors have systematically tested the utility, performance, and reliability of a noninvasive monitor of ICC. The underlying principle of this device is that the ICP transmission and its infrasonic waves are transmitted through the inner ear toward the tympanic membrane. If the outer ear is sealed in an airtight fashion, motions of the tympanic membrane cause air pressure fluctuations that can be recorded using a special sensor.

The authors compared the HFC calculated from an intraparenchymal ICP sensor with that obtained simultaneously from an ipsilaterally placed noninvasive device during half of a respiratory cycle (peak to baseline) as well as for three random samples of three heart cycles. They analyzed 32 sessions in 13 patients in whom mechanical ventilation had been established. In four (11%) of 36 sessions they could not demonstrate an adequate signal.

For the peak-to-baseline cycle, the mean invasively recorded HFC was 8.05 ± 0.55 Hz (range 6.7–9 Hz) whereas the mean noninvasively recorded HFC was 8.04 ± 0.49 Hz (range 7–9.3 Hz). The ICP was 8.5 ± 5 mm Hg (range 2–24 mm Hg). For the three heart cycles randomly sampled, the values were 7.73 ± 0.51 Hz (range 6.7–8.6 Hz) and 7.76 ± 0.56 mm Hg (range 6.5–8.8 mm Hg), respectively.

This device allows noninvasive assessment of ICC based on the HFC waveform analysis that is equivalent to that obtained by invasive intraparenchymal recording. The monitoring device may become a valuable tool for monitoring parameters in patients in whom placement of an intracranial sensor is not feasible but assessment of ICC as an alternative to ICP measurement is desired.
Functional magnetic resonance imaging and control over the biceps muscle after intercostal—musculocutaneous nerve transfer
Authors: Malessy Martijn J. A. , Bakker Dick , Dekker Ad J. , van Dijk J. Gert , Thomeer Ralph T. W. M.
Published: May 2009

Object. Recent progress in the understanding of cerebral plastic changes that occur after an intercostal nerve (ICN)—musculocutaneous nerve (MCN) transfer motivated a study with functional magnetic resonance (fMR) imaging to map reorganization in the primary motor cortex.

Methods. Eleven patients with traumatic root avulsions of the brachial plexus were studied. Nine patients underwent ICN—MCN transfer to restore biceps function and two patients were studied prior to surgery. The biceps muscle recovered well in seven patients who had undergone surgery and remained paralytic in the other two patients. Maps of neural activity within the motor cortex were generated for both arms in each patient by using fMR imaging, and the active pixels were counted. The motor task consisted of biceps muscle contraction. Patients with a paralytic biceps were asked to contract this muscle virtually. The location and intensity of motor activation of the seven surgically treated arms that required good biceps muscle function were compared with those of the four arms with a paralytic biceps and with activity obtained in the contralateral hemisphere regulating the control arms.

Activity could be induced in the seven surgically treated patients whose biceps muscles had regained function and was localized within the primary motor area. In contrast, activity could not be induced in the four patients whose biceps muscles were paralytic. Neither the number of active pixels nor the mean value of their activations differed between the seven arms with good biceps function and control arms. The weighted center of gravity of the distribution of activity also did not appear to differ.

Conclusions. Reactivation of the neural input activity for volitional biceps control after ICN—MCN transfer, as reflected on fMR images, is induced by successful biceps muscle reinnervation. In addition, the restored input activity does not differ from the normal activity regulating biceps contraction and, therefore, has MCN acceptor qualities. After ICN—MCN transfer, cerebral activity cannot reach the biceps muscle following the normal nervous system pathway. The presence of a common input response between corticospinal neurons of the ICN donor and the MCN acceptor seems crucial to obtain a functional result after transfer. It may even be the case that a common input response between donor and acceptor needs to be present in all types of nerve transfer to become functionally effective.
Symptomatic vasospasm and outcomes following aneurysmal subarachnoid hemorrhage: a comparison between surgical repair and endovascular coil occlusion
Authors: Rabinstein Alejandro A. , Pichelmann Mark A. , Friedman Jonathan A. , Piepgras David G. , Nichols Douglas A. , McIver Jon I. , Toussaint L. Gerard , McClelland Robyn L. , Fulgham Jimmy R. , Meyer Fredric B. , Atkinson John L. D. , Wijdicks Eelco F. M.
Published: May 2009

Object. The authors studied patients with aneurysmal subarachnoid hemorrhage (SAH) to determine whether the incidence of symptomatic vasospasm or overall clinical outcomes differed between patients treated with craniotomy and clip application and those treated by endovascular coil occlusion.

Methods. The authors reviewed 415 consecutive patients with aneurysmal SAH who had been treated with either craniotomy and clip application or endovascular coil occlusion at a single institution between 1990 and 2000. Three hundred thirty-nine patients underwent surgical clip application procedures, whereas 76 patients underwent endovascular coil occlusion.

Symptomatic vasospasm occurred in 39% of patients treated with clip application, 30% of patients treated with endovascular coil occlusion, and 37% of patients overall. Compared with patients treated with clip application, patients treated with endovascular coil occlusion were more likely to suffer acute hydrocephalus (50 compared with 34%, p = 0.008) and were more likely to harbor aneurysms in the posterior circulation (53 compared with 20%, p < 0.001). Logistic regression models controlling for patient age, admission World Federation of Neurosurgical Societies (WFNS) grade, acute hydrocephalus, aneurysm location, and day of treatment revealed that, among patients with an admission WFNS grade of I to III, endovascular coil occlusion carried a lower risk of symptomatic vasospasm (odds ratio [OR] 0.34, 95% confidence interval [CI] 0.14—0.8) and death or permanent neurological deficit due to vasospasm (OR 0.28, 95% CI 0.08–1) compared with craniotomy and clip application. Similar models revealed no difference in the likelihood of a Glasgow Outcome Scale score of 3 or less at the longest follow-up review (median 6 months) between treatment groups (OR 0.58, 95% CI 0.28–1.21).

Conclusions. Patients with better clinical grades (WFNS Grades I–III) at hospital admission were less likely to suffer symptomatic vasospasm when treated by endovascular coil occlusion, compared with craniotomy and clip application. Nevertheless, there was no significant difference in overall outcome at the longest follow-up examination between the two treatment groups.