bluuebunny/crossref_metadata_2025 huggingface dataset:
Rare giant cell ependymoma in an octogenarian
Authors: Cooper Patrick B. , Katus Matthew , Moores Leon , Geyer Dennis , Smirniotopoulos James G. , Sandberg Glenn D. , Rushing Elisabeth J.
Published: January 2008

✓Ependymomas are glial tumors that occur most often in children. In adults, ependymomas most often appear in the spinal cord. The World Health Organization recognizes several rare ependymoma subtypes, including the giant cell ependymoma of the terminal filum. The authors describe an unusual case of a posterior fossa giant cell ependymoma in an 89-year-old man presenting with vertigo and disequilibrium. Only seven cases of this tumor have been reported in the literature to date. The authors discuss the clinical presentation, radiological findings, pathological considerations, and surgical intervention in this patient and review the relevant literature.
Myeloid sarcoma with multiple lesions of the central nervous system in a patient without leukemia
Authors: Widhalm Georg , Dietrich Wolfgang , Müllauer Leonhard , Streubel Berthold , Rabitsch Werner , Kotter Mark R. , Knosp Engelbert , Roessler Karl
Published: January 2008

✓ The authors report the unusual case of a 35-year-old woman suffering from left leg numbness and radiculopathy due to multiple lesions in the central nervous system: one right parietal extracranial–intracranial lesion with invasion of the sensory cortex, and two intraspinal, intradural lesions compressing the spinal cord at T3–5 and S1–4. Biopsy sampling of the extracranial part of the parietal lesion led to a diagnosis of myeloid sarcoma. Further examination revealed no evidence of leukemic disease or myeloproliferative disorder. An aggressive multimodal approach to treatment in this patient with a combination of chemotherapy, whole-body radiotherapy, and allogeneic bone marrow transplantation was started immediately. The patient experienced full neurological recovery and complete disappearance of all lesions. At the 7-year follow-up examination, there was no evidence of disease. To the authors’ knowledge, this is the first report of a myeloid sarcoma with both intracranial and intraspinal manifestations in a patient without leukemia.
Use of diffusion tensor imaging to evaluate weakness
Authors: Kim Chi Heon , Chung Chun-Kee , Kim June Sic , Jahng Tae Ahn , Lee June Ho , Song In Chan
Published: January 2008

Object

Recently, diffusion tensor (DT) imaging was introduced to demonstrate white matter tracts. However, research interest has focused on the anatomical rather than the functional aspects of this imaging modality. The authors undertook a functional analysis of DT imaging to determine the relationship between weakness and changes on DT images.

Methods

Diffusion tensor images were obtained in 23 patients with lesions located adjacent to the pyramidal tract. Patients were classified according to their motor deficit. Axial magnetic resonance image sections through the maximum tumor diameters were selected and the mean apparent diffusion coefficients (ADCs) and mean fractional anisotropies (FAs) were measured. One ovoid region of interest (ovROI) was placed in the center of the pyramidal tract and another was designed to include the whole pyramidal tract at the same axial level (wROI). To determine intraobserver variability, a single neurosurgeon measured mean ADCs and FAs four times by using these two different ROI types without knowledge of any clinical information. To determine interobserver variability, a second neurosurgeon who was also unaware of any clinical information measured the mean ADCs and FAs by using the wROI method.

The five measurements produced the same results. The mean FA at the lesion side of the pyramidal tract was significantly lower in patients with weakness (p < 0.01). Little intraobserver measurement variability occurred using the ovROI method, and no interobserver variability occurred using the wROI method.

Conclusions

Motor weakness was significantly related to a low mean FA in the pyramidal tract on the lesion side. Designing an ROI that includes the whole pyramidal tract is an easier and more reproducible method than using an ovROI method.
Gamma Knife surgery for focal brainstem gliomas
Authors: Yen Chun Po , Sheehan Jason , Steiner Melita , Patterson Greg , Steiner Ladislau
Published: January 2008

Object

Focal tumors, a distinct subgroup of which is composed of brainstem gliomas, may have an indolent clinical course. In the past, their management involved monitoring of open-ended imaging studies and shunt placement if cerebrospinal fluid diversion was required. Nonetheless, their treatment remains a significant challenge for neurosurgeons. Gamma Knife surgery (GKS) has recently been tried as an alternative to surgical extirpation. In the present study the authors assess clinical and imaging results in 20 patients who harbored focal brainstem gliomas treated with GKS between 1990 and 2001.

Methods

There were 10 male and 10 female patients with a mean age of 19.1 years. Sixteen tumors were located in the midbrain, three in the pons, and one in the medulla oblongata. The mean tumor volume at the time of GKS was 2.5 cm3. In 10 cases a tumor specimen was obtained either by open surgery or stereotactic biopsy, securing the diagnosis of pilocytic astrocytoma in five patients and nonpilocytic astrocytoma in five others. In the remaining 10 cases, the diagnosis was based on clinical and neuroimaging findings. The prescription Gamma Knife dose varied between 10 and 18 Gy, except in three patients who were receiving a boost to a site in which external-beam radiation was previously delivered. An average of four isocenters were utilized per GKS.

Patients were followed up for a mean of 78.0 months. The tumors disappeared in four patients and shrank in 12 patients. Of these patients, one experienced transitory extrapyramidal symptoms and fluctuating impairment of consciousness (from somnolence to coma) for 6 months. Another patient whose tumor disappeared 3 years following GKS died of stroke 8 years postoperatively. The rest of the patients either remained stable or improved clinically. Tumor progression occurred in four patients; of these four, one patient developed hydrocephalus requiring a ventriculoperitoneal shunt, two showed neurological deterioration, and one 4-year-old boy died of tumor progression.

Conclusions

Gamma Knife surgery may be an effective primary treatment or adjunct to open surgery for focal brainstem gliomas.
Fusion imaging of three-dimensional magnetic resonance cisternograms and angiograms for the assessment of microvascular decompression in patients with hemifacial spasms
Authors: Satoh Toru , Onoda Keisuke , Date Isao
Published: January 2008

Object

The precise preoperative assessment of the complex nerve–vessel relationship at the root exit zone (RExZ) of the facial nerve is important when planning microvascular decompression (MVD) in patients with hemifacial spasms. The authors have developed an imaging technique—the fusion of 3D magnetic resonance (MR) cisternography and coregistered 3D MR angiography images—that allows clear visualization of the spatial relationship between the vessels and the rootlet of the facial nerve at the brainstem.

Methods

The authors reconstructed 3D MR cisternograms and 3D MR angiograms by using a perspective volume-rendering algorithm that they applied to the volumetric data sets of the following modalities: MR cisternography (a T2-weighted 3D fast spin echo sequence) and coregistered MR angiography (a 3D time-of-flight sequence). The complex anatomical relationship between the offending vessels and the facial nerve RExZ was inspected preoperatively by examining the fusion images from various perspectives within the cerebellopontine angle cistern, within the affected facial nerve, and through the simulated surgical route. The reconstructed 3D findings of the nerve–vessel relationship were compared with the intraoperative findings. Postoperatively, the fused 3D MR imaging technique was used to confirm that microsurgical dissection and the interposed prosthesis had succeeded in maintaining the causative vessels in a position away from the RExZ.

Conclusions

The fusion of 3D MR cisternograms and 3D MR angiograms may prove useful in the pre- and postoperative assessment of MVD in patients with hemifacial spasm.
Emergency embolectomy for treatment of acute middle cerebral artery occlusion
Authors: Horiuchi Tetsuyoshi , Nitta Junpei , Sakai Keiichi , Tanaka Yuichiro , Hongo Kazuhiro
Published: January 2008

Object

The authors evaluated the efficacy of emergency embolectomy in patients with acute middle cerebral artery occlusion (MCAO).

Methods

A retrospective review of the charts for patients undergoing embolectomy at the authors’ institution was performed. Between October 1997 and May 2004, 12 patients (mean age 70 years) with acute MCAO were treated using embolectomy. Local intraarterial fibrinolysis with urokinase was initially undertaken in eight of 12 patients. Sufficient recanalization was not achieved with fibrinolysis in any patient, and thus embolectomy was performed immediately thereafter. Recanalization by embolectomy was achieved in all patients (mean occlusion time 6 hours, 11 minutes). Each patient’s condition was evaluated on discharge. Outcomes in the 12 patients according to the Glasgow Outcome Scale were good recovery in five, moderate disability in two, severe disability in three, vegetative state in one, and death due to a cardiac complication in one. None of the 12 patients had symptomatic hemorrhagic infarction.

Conclusions

Emergency embolectomy can be performed in patients with MCAO with minimal morbidity and death. The procedure can be used to achieve good recovery even in patients in whom fibrinolysis is insufficient after acute MCAO and should be a part of the algorithm for the treatment of MCAO.
Ischemic complications associated with resection of opercular glioma
Authors: Kumabe Toshihiro , Higano Shuichi , Takahashi Shoki , Tominaga Teiji
Published: January 2008

Object

Opercular glioma inferolateral to the hand/digit sensorimotor area can be resected safely using a neuronavigation system and functional brain mapping techniques. However, the surgery can still sometimes cause postoperative ischemic complications, the character of which remains unclear. The authors of this study investigated the occurrence of infarction associated with resection of opercular glioma and the arterial supply to this region.

Methods

The study involved 11 consecutive patients with gliomas located in the opercular region around the orofacial primary motor and somatosensory cortices but not involving either the hand/digit area or the insula, who had been treated in their department after 1997. Both pre- and postoperative diffusion-weighted magnetic resonance (MR) imaging was performed in the nine consecutive patients after 1998 to detect ischemic complications. All patients underwent open surgery for maximum tumor resection. Postoperative MR imaging identified infarction beneath the resection cavity in all patients. Permanent motor deficits associated with infarction involving the descending motor pathway developed in two patients. Cadaveric angiography showed that the distributing arteries to the corona radiata were the long insular arteries and/or medullary arteries from the opercular and cortical segments of the middle cerebral artery.

Conclusions

Subcortical resection around the upper limiting sulcus of the posterior region of the insula and wide resection in the anteroposterior and cephalocaudal directions of the opercular region were considered to be risk factors of the critical infarction. Surgeons should be aware that resection of opercular glioma can disrupt the blood supply of the corona radiata, and carries the risk of permanent motor deficits.
Intradural cranial chordoma: a rare presentation of an uncommon tumor
Authors: Roberti Fabio , Sekhar Laligam N. , Jones Robert V. , Wright Donald C.
Published: January 2008

Object

Intracranial intradural chordomas are extremely rare lesions, and only a few cases have been reported in the neurosurgical literature. The authors performed a retrospective analysis of cases treated at their institutions. They present an illustrative surgical scenario and discuss the published literature, pathogenesis, and histopathological features as well as available follow-up data on the clinical behavior of these intradural lesions.

Methods

The authors reviewed clinical, neuroimaging, operative and follow-up data from a series of 79 chordomas treated at their institutions over the last 17 years. They found that the tumors were confined exclusively to the intradural compartment in only three cases. Staining for MIB-1 was performed to support the differential diagnosis between ecchordosis physaliphora and intradural chordoma, and in all three patients the neoplastic nature of the lesions was confirmed. None of these three cases showed recurrence of the lesion at midterm follow up.

Conclusions

Complete resection, followed by close clinical and neuroradiological follow up, is warranted in cases of intradural cranial chordoma.
Detection of cerebral ischemia in neurovascular surgery using quantitative frequency-domain near-infrared spectroscopy
Authors: Calderon-Arnulphi Mateo , Alaraj Ali , Amin-Hanjani Sepideh , Mantulin William W. , Polzonetti Chiara M. , Gratton Enrico , Charbel Fady T.
Published: January 2008

Object

There is great value in monitoring for signs of ischemia during neurovascular procedures. Current intraoperative monitoring techniques provide real-time feedback with limited accuracy. Quantitative frequency-domain near-infrared spectroscopy (Q-NIRS) allows measurement of tissue oxyhemoglobin (HbO2), deoxyhemoglobin (HHb), and total hemoglobin (tHb) concentrations and brain tissue oxygen saturation (SO2), which could be useful when monitoring for evidence of intraoperative ischemia.

Methods

Using Q-NIRS, the authors monitored 25 neurovascular procedures including aneurysm clip placement, arteriovenous malformation resection, carotid endarterectomy, superficial temporal artery–middle cerebral artery (MCA) bypass surgery, external carotid artery–MCA bypass surgery, encephaloduromyosynangiosis, and balloon occlusion testing. The Q-NIRS technology provides measurable cerebral oxygenation values independent from those of the scalp tissue. Thus, alterations in the variables measured with Q-NIRS quantitatively reflect cerebral tissue perfusion. Bilateral monitoring was performed in all cases.

Five of the patients exhibited evidence of clinical ischemic events during the procedures. One patient suffered blood loss with systemic hypotension and developed diffuse brain edema intraoperatively, one patient suffered an ischemic event intraoperatively and developed an occipital stroke postoperatively, and one patient showed slowing on electroencephalography intraoperatively during carotid clamping; in two patients balloon occlusion testing failed. In all cases of ischemic events occurring during the procedure, Q-NIRS monitoring showed a decrease in HbO2, tHb, and SO2, and an increase in HHb.

Conclusions

Quantitative frequency-domain near-infrared spectroscopy provides quantifiable and continuous real-time information about brain oxygenation and hemodynamics in a noninvasive manner. This continuous intraoperative oxygenation monitoring is a promising method for detecting ischemic events during neurovascular procedures.
Cerebral aneurysm progression suppressed by blockage of endothelin B receptor
Authors: Sadamasa Nobutake , Nozaki Kazuhiko , Takagi Yasushi , Moriwaki Takuya , Kawanabe Yoshifumi , Ishikawa Masatsune , Hashimoto Nobuo
Published: January 2008

Object

Cerebral aneurysm is a major cause of subarachnoid hemorrhage, but the mechanisms of its development remain unclear. Mechanical stretch has been reported to induce vascular smooth-muscle cell apoptosis via endothelin B receptors (ETBRs). The objectives of this study were to clarify the expression and localization of ETBR in cerebral aneurysms and to examine the effect of ETBR blockage on the development of experimental cerebral aneurysms.

Methods

Seventy-two rats underwent a cerebral aneurysm induction procedure and were divided into four groups according to the duration of postoperative study periods. Expression of ETBR was confirmed by reverse transcription–polymerase chain reaction and immunohistochemical analysis. The authors also studied the effect of K-8794, an oral selective antagonist of ETBR, to see whether it would influence the formation of cerebral aneurysms.

Two weeks after the aneurysm induction procedure, ETBR was rarely detected in anterior cerebral artery–olfactory artery bifurcations, but it was weakly expressed in experimental cerebral aneurysms at 1 month after the procedure, and markedly expressed at 3 months. The administration of K-8794 for 1 month after the procedure significantly reduced the number of advanced aneurysms and the number of apoptotic smooth-muscle cells.

Conclusions

These results suggest that ETBR might play a significant role in the progression of cerebral aneurysms and have the potential to improve prevention and treatment of cerebral aneurysms.
Neural injury and recovery near cortical contusions: a clinical magnetic resonance spectroscopy study
Authors: Nakabayashi Motoaki , Suzaki Shinichiro , Tomita Hiroki
Published: January 2008

Object

Proton magnetic resonance (MR) spectroscopy can detect neural metabolic alterations noninvasively after traumatic brain injury (TBI) even in areas that appear normal. Unlike metabolic depression in diffuse TBI, focal metabolic alterations near cortical contusions in humans have not been previously investigated in a longitudinal study. The object of this study was to identify these alterations and examine their course.

Methods

At 1 week and 1 month after mild to moderate TBI involving cortical contusion, 30 patients underwent 1H MR spectroscopy examination that focused bilaterally on normal-appearing frontal and temporal white matter. Levels of N-acetylaspartate (NAA), choline (Cho) compounds, and creatine (Cr) were measured to obtain two metabolite ratios, NAA/Cr and Cho/Cr. The ratios were compared with those of 11 healthy individuals.

At 1 week after TBI, the NAA/Cr ratio was significantly lower near cortical contusions than it was in white matter remote from the injury or in controls, while the Cho/Cr ratios did not differ significantly. At 1 month, the decreased NAA/Cr ratios near contusions had increased significantly from 1 week, as had the Cho/Cr ratio.

Conclusions

Metabolic depression reflecting neural injury was apparent in subjacent normal-appearing white matter at 1 week after cortical contusion; this had normalized substantially at 1 month.
A retrospective analysis of reasons for reoperation following initially successful peripheral nerve stimulation
Authors: Ishizuka Kelly , Oaklander Anne Louise , Chiocca E. Antonio
Published: January 2008

Object

The authors investigated the causes for surgical reexploration in patients with complex regional pain syndrome Type II who received initial relief of pain from implantation of a peripheral nerve stimulator (PNS).

Methods

The authors reviewed the charts of 11 consecutive patients who underwent a total of 27 PNS-related operations at one institution. Duration of follow up ranged from 5 days to more than 24 months. Of 11 patients who received PNS implants, seven (64%) required one or more additional surgeries to relocate the PNS because initial pain relief following stimulation was lost and not restored by changing pulse generator settings. Loss of analgesia was attributed to migration of the sutured electrode strip paddle (nine [33%] of 27 surgeries), infection (four [15%] of 27), and the need for placement in an alternative location (three [11%] of 27).

Conclusions

Although infection is attributable to surgical technique, most complications requiring repeated surgery (nine [33%] of 27) are caused by equipment design. Changes in PNS design or in implantation technique might substantially reduce the need for reoperation after PNS implantation.
Direct repair (nerve grafting), neurotization, and end-to-side neurorrhaphy in the treatment of brachial plexus injury
Authors: Haninec Pavel , Šámal Filip , Tomáš Robert , Houstava Ladislav , Dubový Petr
Published: January 2008

Object

The authors present the long-term results of nerve grafting and neurotization procedures in their group of patients with brachial plexus injuries and compare the results of “classic” methods of nerve repair with those of end-to-side neurorrhaphy.

Methods

Between 1994 and 2006, direct repair (nerve grafting), neurotization, and end-to-side neurorrhaphy were performed in 168 patients, 95 of whom were followed up for at least 2 years after surgery. Successful results were achieved in 79% of cases after direct repair and in 56% of cases after end-to-end neurotization. The results of neurotization depended on the type of the donor nerve used. In patients who underwent neurotization of the axillary and the musculocutaneous nerves, the use of intraplexal nerves (motor branches of the brachial plexus) as donors of motor fibers was associated with a significantly higher success rate than the use of extraplexal nerves (81% compared with 49%, respectively, p = 0.003). Because of poor functional results of axillary nerve neurotization using extraplexal nerves (success rate 47.4%), the authors used end-to-side neurorrhaphy in 14 cases of incomplete avulsion. The success rate for end-to-side neurorrhaphy using the axillary nerve as a recipient was 64.3%, similar to that for neurotization using intraplexal nerves (68.4%) and better than that achieved using extraplexal nerves (47.4%, p = 0.19).

Conclusions

End-to-side neurorrhaphy offers an advantage over classic neurotization in not requiring sacrifice of any of the surrounding nerves or the fascicles of the ulnar nerve. Typical synkinesis of muscle contraction innervated by the recipient nerve with contraction of muscles innervated by the donor was observed in patients after end-to-side neurorrhaphy.
The suprapetrosal craniotomy
Authors: Ribas Guilherme Carvalhal , Rodrigues Aldo Junqueira
Published: January 2008

Object

The primary aim of this study was to establish standard sites for bur holes that maintain constant anatomical relationships with the skull base and neural structures and can serve as the basal aspect of supratentorial temporooccipital craniotomies.

Methods

To determine cranial–cerebral relationships, the authors created bur holes in 16 adult cadaveric skulls. Three bur holes were made on each side of the skulls (32 cerebral hemispheres). The authors then introduced plastic catheters through the bur holes to evaluate pertinent cranial and neural landmarks.

The first bur hole, located anterior to the auricle of the ear, appeared to have a particular anatomical relationship with the anterior aspect of the petrous portion of the temporal bone and the most anterior aspect of the midbrain. The second bur hole, whose base was located 1 cm above the interface of the parietomastoid and squamous sutures, had a particular relationship with the posterior border of the petrous portion of the temporal bone and with the posterior aspect of the midbrain. The third bur hole, whose base was located 1 cm above the asterion, was mostly supratentorial and particularly related to the preoccipital notch.

Conclusions

The preauricular bur hole and the bur hole whose base was located 1 cm above the interface of the parietomastoid and squamous sutures delimit anteriorly and posteriorly the external projection of the petrous bone and the midbrain. The middle fossa floor is located anterior to the site of the preauricular bur hole, and the superior surface of the tentorium is posterior to the bur hole located above the parietomastoid–squamous suture interface. Together with the bur hole whose base is located above the asterion, these bur holes can be considered standards for temporooccipital craniotomies.
Chromosome arm 1q gain associated with good response to chemotherapy in a malignant glioma
Authors: Takahashi Satoshi , Hirose Yuichi , Ikeda Eiji , Fukaya Raita , Kawase Takeshi
Published: January 2008

✓The authors describe the case of a patient with a glioblastoma multiforme who showed remarkably good response to chemotherapy. A genetic analysis using comparative genomic hybridization (CGH) revealed that the tumor had a gain on the q arm of chromosome 1 (1q). Using CGH for a series of genetic analyses of more than 180 patients with gliomas, six were found to have a demonstrated 1q gain. Although the tumors in all six of these cases were histopathologically diagnosed as high-grade gliomas, compared with other malignant gliomas they demonstrated a good prognosis because of their favorable chemotherapeutic sensitivity. In immunohistochemical tests, most of the tumor cells in these cases were negative for O6-methylguanine–DNA methyltransferase, which antagonizes the effect of DNA-alkylating chemotherapeutic agents. The authors believed that a gain of 1q could be produced through the genetic events that cause loss of 1p, because these chromosomal aberrations have an imbalance of DNA copy number in common (1p <1q). A gain of 1q is an infrequent chromosomal aberration and its clinical importance should be investigated in a larger study; however, patients with malignant gliomas demonstrating a 1q gain possibly show longer survival and good response to chemotherapy similar to patients with tumors demonstrating 1p loss. The importance of using genetic analysis for gliomas is emphasized in this report because it may help in selecting cases responsive to chemotherapy and because appropriate treatment for these patients will lead to progress in the treatment of malignant gliomas.
Lack of utility of arteriojugular venous differences of lactate as a reliable indicator of increased brain anaerobic metabolism in traumatic brain injury
Authors: Poca Maria A. , Sahuquillo Juan , Vilalta Anna , Garnacho Angel
Published: January 2008

Object

Ischemic lesions are highly prevalent in patients with traumatic brain injuries (TBIs) and are the single most important cause of secondary brain damage. The prevention and early treatment of these lesions is the primary aim in the modern treatment of these patients. One of the most widely used monitoring techniques at the bedside is quantification of brain extracellular level of lactate by using arteriojugular venous differences of lactate (AVDL). The purpose of this study was to determine the sensitivity, specificity, and predictive value of AVDL as an indicator of increases in brain lactate production in patients with TBIs.

Methods

Arteriojugular venous differences of lactate were calculated every 6 hours using samples obtained though a catheter placed in the jugular bulb in 45 patients with diffuse head injuries (57.8%) or evacuated brain lesions (42.2%). Cerebral lactate concentration obtained with a 20-kD microdialysis catheter implanted in undamaged tissue was used as the de facto gold standard.

Six hundred seventy-three AVDL determinations and cerebral microdialysis samples were obtained simultaneously; 543 microdialysis samples (81%) showed lactate values greater than 2 mmol/L, but only 21 AVDL determinations (3.1%) showed an increase in brain lactate. No correlation was found between AVDL and cerebral lactate concentration (ρ = 0.014, p = 0.719). Arteriojugular venous differences of lactate had a sensitivity and specificity of 3.3 and 97.7%, respectively, with a false-negative rate of 96.7% and a false-positive rate of 2.3%.

Conclusions

Arteriojugular venous differences of lactate do not reliably reflect increased cerebral lactate production and consequently are not reliable in ruling out brain ischemia in patients with TBIs. The clinical use of this monitoring method in neurocritical care should be reconsidered.
Treatment for posterior fossa dissemination of primary supratentorial glioma
Authors: Smith Justin S. , Parney Ian F. , Lamborn Kathleen R. , McDermott Michael W. , Sneed Penny K. , Chang Susan M.
Published: January 2008

Object

This study was designed to assess the presentation, management, and outcome of cases involving patients who had a supratentorial glioma that subsequently progressed in the posterior fossa (PF).

Methods

The authors performed a retrospective chart review of adult patients treated between 1997 and 2005 for supratentorial gliomas that progressed in the PF. The 29 patients with PF progression in this study were relatively young (median age of 34 years at original presentation). Twenty of these patients presented with symptoms. The symptoms were typically nonspecific to this population, at times leading to delays in diagnosis. Overall, these symptoms resolved in eight patients (40%) and progressed or remained unchanged in 12 (60%). Patients treated with more than 5000 cGy of radiation administered to the PF were more likely to have symptom resolution than those who received any other form of treatment, including reduced doses of radiation (p = 0.004). The patients treated with higher doses also survived significantly longer after PF progression (univariate analysis, p = 0.01, and after adjusting for tumor grade, p = 0.04).

Conclusions

Patients with PF progression of supratentorial infiltrative gliomas may benefit from treatment, and the authors recommend more than 5000 cGy of radiation to the PF if prior radiotherapy ports and doses allow.
Increase in glutamate as a sensitive indicator of extracellular matrix integrity in peritumoral edema: a 3.0-tesla proton magnetic resonance spectroscopy study
Authors: Kimura Teruo , Ohkubo Masaki , Igarashi Hironaka , Kwee Ingrid L. , Nakada Tsutomu
Published: January 2008

Object

The authors of previous studies based on diffusion tensor imaging have indicated that there are two types of peritumoral edema—namely, edema with preserved structural integrity of the glial matrix and edema with compromised glial matrix. The authors of this study hypothesized that functionality of the glutamate (Glu)–glutamine shuttle, a vital neuron–glia interaction, may be differentially affected by peritumoral edema. They tested this hypothesis using proton magnetic resonance (MR) spectroscopy on a 3.0-tesla system that is capable of quantifying Glu without need of editing.

Methods

Twenty-three patients, each with a single brain tumor mass and peritumoral edema (nine high-grade gliomas, eight metastatic brain tumors, and six meningiomas), and nine healthy individuals participated in this study. Single-voxel proton MR imaging targeting the region of peritumoral edema was performed using a 3.0-tesla system.

Glutamate levels in the peritumoral edema of nonglial tumors was significantly elevated (p < 0.01) compared with edema associated with glial tumors or normal white matter. The finding confirmed that peritumoral edema in nonglial tumors is distinct from that of glial tumors, as previously indicated in diffusion tensor imaging studies. The authors hypothesized that the former condition represents a compensatory increase in activities of the Glu–glutamine shuttle brought about by simple expansion of the extracellular space due to edema.

Conclusions

The assessment of Glu concentrations in peritumoral edema using 3.0-tesla proton MR spectroscopy may be developed into an objective index of the structural integrity of the glial matrix.
Correlation of magnetic resonance spectroscopic and growth characteristics within Grades II and III gliomas
Authors: McKnight Tracy R. , Lamborn Kathleen R. , Love Tonya D. , Berger Mitchel S. , Chang Susan , Dillon William P. , Bollen Andrew , Nelson Sarah J.
Published: January 2008

Object

The accurate diagnosis of World Health Organization Grades II and III gliomas is crucial for the effective treatment of patients with such lesions. Increased cell density and mitotic activity are histological features that distinguish Grade III from Grade II gliomas. Because increased cellular proliferation and density both contribute to the in vivo magnetic resonance (MR) spectroscopic peak corresponding to choline-containing compounds (Cho), the authors hypothesized that multivoxel MR spectroscopy might help identify the tumor regions with the most aggressive growth characteristics, which would be optimal locations for biopsy. They investigated the ability to use one or more MR spectroscopic parameters to predict the MIB-1 cell proliferation index (PI), the terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling cell death index (DI), the cell density, and the ratio of proliferation to cell death (PI/DI) within different regions of the same tumor.

Methods

Patients with presumed Grades II or III glioma underwent 3D MR spectroscopic imaging prior to surgery, and two or three regions within the tumor were targeted for biopsy retrieval based on their spectroscopic features. Biopsy specimens were extracted from the tumor during image-guided resection, and the PI, DI, and cell density were assessed in the specimens using immunohistochemical methods.

Conclusions

The authors found that the relative levels of Cho and N-acetylaspartate (NAA) correlated with the cell density, PI, and PI/DI ratio within different regions of the same tumor and that the association held for the subpopulation of nonenhancing tumors. The association was stronger in tumors with large ranges of Cho/NAA values, irrespective of the presence of contrast enhancement. The findings demonstrate the validity of using MR spectroscopy to identify regions of aggressive growth in presumed Grade II or III gliomas that would be suitable targets for retrieving diagnostic biopsy specimens.
Pressure-dependent effect of shock waves on rat brain: induction of neuronal apoptosis mediated by a caspase-dependent pathway
Authors: Kato Kaoruko , Fujimura Miki , Nakagawa Atsuhiro , Saito Atsushi , Ohki Tomohiro , Takayama Kazuyoshi , Tominaga Teiji
Published: January 2008

Object

Shock waves have been experimentally applied to various neurosurgical treatments including fragmentation of cerebral emboli, perforation of cyst walls or tissue, and delivery of drugs into cells. Nevertheless, the application of shock waves to clinical neurosurgery remains challenging because the threshold for shock wave–induced brain injury has not been determined. The authors investigated the pressure-dependent effect of shock waves on histological changes of rat brain, focusing especially on apoptosis.

Methods

Adult male rats were exposed to a single shot of shock waves (produced by silver azide explosion) at over-pressures of 1 or 10 MPa after craniotomy. Histological changes were evaluated sequentially by H & E staining and terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling (TUNEL). The expression of active caspase-3 and the effect of the nonselective caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK) were examined to evaluate the contribution of a caspase-dependent pathway to shock wave–induced brain injury.

High-overpressure (> 10 MPa) shock wave exposure resulted in contusional hemorrhage associated with a significant increase in TUNEL-positive neurons exhibiting chromatin condensation, nuclear segmentation, and apoptotic bodies. The maximum increase was seen at 24 hours after shock wave application. Low-overpressure (1 MPa) shock wave exposure resulted in spindle-shaped changes in neurons and elongation of nuclei without marked neuronal injury. The administration of Z-VAD-FMK significantly reduced the number of TUNEL-positive cells observed 24 hours after high-overpressure shock wave exposure (p < 0.01). A significant increase in the cytosolic expression of active caspase-3 was evident 24 hours after high-overpressure shock wave application; this increase was prevented by Z-VAD-FMK administration. Double immunofluorescence staining showed that TUNEL-positive cells were exclusively neurons.

Conclusions

The threshold for shock wave–induced brain injury is speculated to be under 1 MPa, a level that is lower than the threshold for other organs. High-overpressure shock wave exposure results in brain injury, including neuronal apoptosis mediated by a caspase-dependent pathway. This is the first report in which the pressure-dependent effect of shock wave on the histological characteristics of brain tissue is demonstrated.
The nerve to the mylohyoid as a donor for facial nerve reanimation procedures: a cadaveric feasibility study
Authors: Tubbs R. Shane , Loukas Marios , Shoja Mohammadali M. , Acakpo-Satchivi Leslie , Wellons John C. , Blount Jeffrey P. , Oakes W. Jerry
Published: January 2008

Object

Facial nerve injury with resultant facial muscle paralysis is disfiguring and disabling. Reanimation of the facial nerve has been performed using different regional nerves. The nerve to the mylohyoid has not been previously explored as a donor nerve for facial nerve reanimation procedures.

Methods

Five fresh adult human cadavers (10 sides) were dissected to identify an additional nerve donor candidate for facial nerve neurotization. Using a curvilinear cervicofacial skin incision, the nerve to the mylohyoid and facial nerve were identified. The nerve to the mylohyoid was transected at its point of entrance into the anterior belly of the digastric muscle. Measurements were made of the length and diameter of the nerve to the mylohyoid, and this nerve was repositioned superiorly to the various temporofacial and cervicofacial parts of the extracranial branches of the facial nerve.

All specimens had a nerve to the mylohyoid. The mean length of this nerve available inferior to the mandible was 5.5 cm and the mean diameter was 1 mm. In all specimens, the nerve to the mylohyoid reached the facial nerve stem and the temporofacial and cervicofacial trunks without tension. No gross evidence of injury to surrounding neurovascular structures was identified.

Conclusions

To the authors' knowledge, the use of the nerve to the mylohyoid for facial nerve reanimation has not been explored previously. Based on the results of this cadaveric study, the use of the nerve to the mylohyoid may be considered for facial nerve reanimation procedures.
Inhibition of Src tyrosine kinase and effect on outcomes in a new in vivo model of surgically induced brain injury
Authors: Jadhav Vikram , Matchett Gerald , Hsu Frank P. K. , Zhang John H.
Published: January 2008

Object

Brain tissue at the periphery of a neurosurgical resection site is vulnerable to injury by a variety of mechanisms including direct trauma, edema, hemorrhage, retractor stretch, and electrocautery. The goal in the present study was to develop an in vivo model of surgically induced brain injury and to test an Src tyrosine kinase inhibitor for neuro-protective properties in this model.

Methods

The authors developed a new surgically induced brain injury model in rats. This model involves resection of part of the frontal lobe. Sprague–Dawley male rats weighing between 300 and 350 g were divided randomly into four groups: Group 1, surgical injury with vehicle treatment; Group 2, surgical injury after treatment with PP1 (an Src tyrosine kinase inhibitor with known neuroprotective properties); Group 3, sham surgery; and Group 4, control. Postoperative assessment included blood–brain barrier (BBB) permeability studies, and histological, immunohistochemical, and Western blot analyses. The authors found that surgical injury caused localized edema and disruption of the BBB compared with findings in the sham surgery group. Treatment with PP1 was associated with decreased edema, decreased breakdown of the BBB, decreased expression of both vascular endothelial growth factor and phosphorylated extracellular signal–regulated kinase 1 and 2, and preservation of ZO-1 expression.

Conclusions

In this study the authors describe a simple and reproducible in vivo animal model of surgically induced brain injury. Pretreatment with PP1 results in improved outcomes in this model, which suggests a possible role for Src tyrosine kinase inhibitors as preoperative therapy for planned neurosurgical procedures.
From manuscript submission to publication: a tour of the Journal of Neurosurgery Publishing Group
Authors: Eliason Jo Ann M.
Published: January 2008

✓The author offers a “soup-to-nuts” description of day-to-day operations at the Journal of Neurosurgery Publishing Group. The route a manuscript follows from submission to publication is outlined and placed within the context of a brief history of the Journal of Neurosurgery and its related journals.
A new method for superselective middle cerebral artery infusion in the rat
Authors: Woitzik Johannes , Schilling Lothar
Published: January 2008

Object

Selective intraarterial drug delivery is used to achieve enhanced local uptake with reduced systemic side effects. In the present paper the authors describe and characterize a new microcatheter-based model of superselective perfusion of the middle cerebral artery (MCA) in rats combined with blockade of blood flow through the MCA.

Methods

Selectivity of administration was shown by infusion of Evans blue which diffusely stained the MCA territory, indicating an increased permeability of the blood–brain barrier during the blockade of blood flow to the MCA. Perfusion of autologous blood through the microcatheter resulted in a flow rate–related increase in the cerebral blood flow measured by laser Doppler flowmetry. Similarly, infusion of an artificial O2 carrier, Oxycyte, was accompanied by an increase in tissue oxygenation as measured using a Licox sensor. Blockade of blood flow to the MCA with the new microcatheter for an extended period of time resulted in the development of ischemia, which was comparable to that induced by intravascular occlusion using a silicone-coated thread. In a 24-hour MCA occlusion model, selective administration of a low dose of MK-801 (0.3 mg/kg body weight) resulted in a significantly smaller infarct volume than systemic application (339 ± 53 mm3 compared with 508 ± 26 mm3, p < 0.001).

Conclusions

This new model of superselective MCA infusion is a valuable tool for investigating the effect of selective delivery and enhanced drug uptake into cerebral ischemic tissue. Without constant blockade of blood flow through the MCA it may also be useful for enhanced drug uptake, gene transfer, or application of stem cells in other neuro-pathological conditions.
Microsurgical anatomy of the mesencephalic veins
Authors: Ardeshiri Ardavan , Ardeshiri Ardeshir , Linn Jennifer , Tonn Jörg-Christian , Winkler Peter A.
Published: January 2008

Object

The mesencephalic veins drain crucial brainstem areas. Due to the narrowness of the tentorial notch, these veins can become obstructed as a result of herniation or surgery, leading to hemorrhage and severe consequences for the patient. There is little in the literature about the mesencephalic veins. The aim of this study was to perform an exact analysis of their microanatomy.

Methods

Fifty-two cadaveric hemispheres were examined under an operating microscope, and measurements were made with a digital caliper. The authors focused on the basal vein (BV), pontomesencephalic vein (PMV), peduncular vein (PV), lateral mesencephalic vein (LMV), and other smaller veins.

The PMV was identified in 84.6% of specimens (mean diameter 0.54 mm); the PV, in 86.5% (mean diameter 0.86 mm); and the LMV, in 100% (mean diameter 1.07 mm). Four types of LMV were identified on the basis of the vein's course. Other smaller veins were also differentiated according to whether they drained mainly the cerebral peduncle, the lemniscal trigone, or the tectum. These veins and their junctions with other veins were depicted.

Conclusions

A thorough understanding of the microanatomy of the mesencephalic veins is crucial in brainstem surgery in order to avoid brain damage due to venous infarction and subsequent edema. Because knowledge of the course, variations, and outflow system of these veins could improve surgical outcome, they warrant special attention during surgery.
Stent fracture and restenosis after placement of a drug-eluting device in the vertebral artery origin and treatment with the stent-in-stent technique
Authors: Kim Seong-Rim , Baik Min-Woo , Yoo Seung-Hoon , Park Ik-Seong , Kim Sang-Don , Kim Moon-Chan
Published: January 2008

✓ The authors report two cases of stent fracture and restenosis after placement of a drug-eluting device in the vertebral artery (VA) origin, and describe management of restenosis with the stent-in-stent technique. Two women, one 62 and the other 67 years of age, underwent stent placement in the VA origin to treat symptomatic and angiographically significant stenosis in this vessel. Sirolimus-eluting coronary stents (Cypher) were used in both cases. Four months after placement of the devices, the symptoms recurred. Follow-up angiography performed 5 months after insertion of the devices revealed a transverse stent fracture with separation of the fragments and severe in-stent restenosis in both cases. The restenoses were treated with reinsertion of coronary stents (Cypher and Jostent FlexMaster) by using the stent-in-stent technique. After stent reinsertion, the patients exhibited relief of symptoms.

This paper is the first report of fracture in a drug-eluting stent and restenosis after stent placement in the VA origin. Restenosis caused by such a fracture can be managed successfully by performing the stent-in-stent maneuver. The physical properties of metallic devices, stent strut geometry, and anatomical peculiarities of the subclavian artery may be associated with stent fractures. Earlier follow-up angiography studies (within 6 months) are warranted.
Identification of venous variants in the pineal region with 3D preoperative computed tomography and magnetic resonance imaging navigation
Authors: Giordano Mario , Wrede Karsten H. , Stieglitz Lennart H. , Samii Madjid , Lüdemann Wolf O.
Published: January 2008

Object

The purpose of this study was to determine the ability of software-assisted 3D reconstruction performed using a neuronavigation system to delineate the anatomy and variation patterns of the pineal region venous complex, and then to compare these data with previous anatomical findings.

Methods

The authors retrospectively reviewed the neuroimages obtained in 100 patients with intracranial lesions (50 computed tomography [CT] scans obtained with contrast agents and 50 magnetic resonance [MR] images obtained with gadolinium) by using a neuronavigation workstation for 3D reconstruction. Particular attention was given to the internal cerebral vein, basal vein (BV), and the vein of Galen. The various connection patterns between the major vessels were classified and statistically analyzed.

Conclusions

The venous system of the pineal region shows a wide range of sex-related variations. In the female patient the absence of a BV (Type 0) is significantly more frequent than in the male. In this study the authors illustrate the ability to depict the venous drainage patterns in the pineal region for all cases studied by using 3D neuronavigation software without the need for additional examinations. This simple tool provides important information for surgical planning and may be of significant help intraoperatively.