bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of cerebral perfusion pressure on contusion volume following impact injury
Authors: Kroppenstedt Stefan-Nikolaus , Kern Michael , Thomale Ulrich-Wilhelm , Schneider Gerd-Helge , Lanksch Wolfgang Reinhardt , Unterberg Andreas Wilhelm
Published: May 2009

Object. Although it is generally acknowledged that a sufficient cerebral perfusion pressure (CPP) is necessary for treatment of severe head injury, the optimum CPP is still a subject of debate. The purpose of this study was to investigate the effect of various levels of blood pressure and, thereby, CPP on posttraumatic contusion volume.

Methods. The left hemispheres of 60 rats were subjected to controlled cortical impact injury (CCII). In one group of animals the mean arterial blood pressure (MABP) was lowered for 30 minutes to 80, 70, 60, 50, or 40 mm Hg 4 hours after contusion by using hypobaric hypotension. In another group of animals the MABP was elevated for 3 hours to 120 or 140 mm Hg 4 hours after contusion by administering dopamine. The MABP was not changed in respective control groups. Intracranial pressure (ICP) was monitored with an ICP microsensor. The rats were killed 28 hours after trauma occurred and contusion volume was assessed using hematoxylin and eosin—stained coronal slices. No significant change in contusion volume was caused by a decrease in MABP from 94 to 80 mm Hg (ICP 12 ± 1 mm Hg), but a reduction of MABP to 70 mm Hg (ICP 9 ± 1 mm Hg) significantly increased the contusion volume (p < 0.05). A further reduction of MABP led to an even more enlarged contusion volume. Although an elevation of MABP to 120 mm Hg (ICP 16 ± 2 mm Hg) did not significantly affect contusion volume, there was a significant increase in the contusion volume at 140 mm Hg MABP (p < 0.05; ICP 18 ± 1 mm Hg).

Conclusions. Under these experimental conditions, CPP should be kept within 70 to 105 mm Hg to minimize posttraumatic contusion volume. A CPP of 60 mm Hg and lower as well as a CPP of 120 mm Hg and higher should be considered detrimental.
Tamoxifen radiosensitization in human glioblastoma cell lines
Authors: Donson Andrew M. , Weil Michael D. , Foreman Nicholas K.
Published: May 2009

Object. A combined tamoxifen and radiation therapy is being used in clinical trials to treat glioblastoma multiforme (GBM). The rationale behind this therapy is that tamoxifen is a radiosensitizer. However, the evidence for this is weak. The authors, therefore, examined the effect of combined radiation—tamoxifen therapy in three GBM cell lines of human origin.

Methods. The GBM cell lines were exposed to different concentrations (0.3–5 µg/ml) of tamoxifen and subsequently irradiated at varying doses (0.8–5 Gy). Tumor growth inhibition was measured using a proliferation assay. The interaction of tamoxifen and radiation therapies was quantified using the combination index method, which distinguishes whether a combined antitumor effect is synergistic, additive, or antagonistic. At high doses of tamoxifen or radiation there was significant inhibition of tumor cell proliferation. At low doses of either therapeutic agent, there was little effect. In one cell line, synergism occurred at high doses of tamoxifen and radiation. In the other two cell lines, an additive effect was observed. In only one of the three cell lines was there synergy between tamoxifen and radiation at doses that significantly inhibited tumor proliferation.

Conclusions. Because synergy could not be demonstrated in all three cell lines at active dosages, the clinical combination of tamoxifen and radiation therapies may not be of benefit to all patients.
Anatomical and embryological considerations in the repair of a large vertex cephalocele
Authors: Hoving Eelco , Blaser Susan , Kelly Edmond , Rutka James T.
Published: May 2009

✓ The case of a neonate with a large vertex cephalocele is presented. The anatomical features of this anomaly were evaluated by means of magnetic resonance imaging and magnetic resonance angiography. Fusion of the thalami, dysgenesis of the corpus callosum, and failure of adequate formation of the interhemispheric fissure were characteristics of the major cerebral anomalies associated with the cephalocele. The absence of a falx in the midline, a split configuration of the superior sagittal sinus, and a dysgenetic tentorium with a concomitant abnormal venous drainage pattern were found in association with a large dorsal cyst. Repair of the anomaly was undertaken on the 3rd postnatal day. A cerebrospinal fluid shunt was required to treat hydrocephalus on Day 30. The child is well at age 3 years, but with significant developmental delay. The pathogenesis of this vertex cephalocele relates to semilobar holoprosencephaly and dorsal cyst formation. In addition, a disturbance in the separation of the diencephalic portion of the neural tube from the surface ectoderm or skin during the final phases of neurulation had occurred to help create the large cephalocele. Detailed preoperative imaging studies and awareness of the embryology and anatomy of this lesion facilitated the repair of the cephalocele. The prognosis of the child is determined not only by the presence of hydrocephalus, but also by the number of associated major cerebral anomalies. Options for treatment are discussed.
Primary cerebellar glioblastomas multiforme in children
Authors: Kulkarni Abhaya V. , Becker Laurence E. , Jay Venita , Armstrong Derek C. , Drake James M.
Published: May 2009

✓ Primary cerebellar glioblastomas multiforme are exceedingly rare in children. The authors therefore retrospectively characterized the clinical behavior and pathological features of these tumors. A review of the database at the Hospital for Sick Children, Toronto, Canada revealed four patients with cerebellar tumors that displayed significant pleomorphism, hypercellularity, mitoses, and necrosis with pseudopalisading. The authors performed a detailed clinical, radiological, histological, and immunohistochemical analysis of the tumors in these four children (three boys and one girl; average age at presentation 7 years; range 21 months–15 years). Magnetic resonance imaging and computerized tomography most commonly revealed a large lesion with minimal edema, inhomogeneous contrast enhancement, and a discrete border. Tumor resection was subtotal in one patient and gross total in three patients. Immunostaining of the tumor cells with antisera to glial fibrillary acidic protein and vimentin was positive in varying degrees. Initial adjuvant therapy consisted of local radiation only (one patient), chemotherapy only (one patient), and radiation and chemotherapy (one patient). One patient received no adjuvant therapy. Tumor recurrence was documented in all patients: two local recurrences (at 3.5 and 7 months), one spinal recurrence (at 14 months), and one local recurrence with ventricular and spinal spread (at 8 months). Ultimately, three of the four patients developed leptomeningeal tumor spread. Patient follow up ranged from 8 to 17 months (mean 12.5 months). Three patients were dead at last follow up with a mean survival of 15 months.

The prognosis for patients with cerebellar glioblastomas is extremely poor, and the tumor has a tendency for cerebrospinal fluid dissemination. The optimal management of patients harboring of these difficult-to-treat tumors, including the role of craniospinal radiation and chemotherapy, has not yet been achieved.
Hyperactive rhizopathy of the vagus nerve and microvascular decompression
Authors: Resnick Daniel K. , Jannetta Peter J.
Published: May 2009

✓ A 37-year-old woman underwent microvascular decompression of the superior vestibular nerve for disabling positional vertigo. Immediately following the operation, she noted severe and spontaneous gagging and dysphagia. Multiple magnetic resonance images were obtained but failed to demonstrate a brainstem lesion and attempts at medical management failed. Two years later she underwent exploration of the posterior fossa. At the second operation, the vertebral artery as well as the posterior inferior cerebellar artery were noted to be compressing the vagus nerve. The vessels were mobilized and held away from the nerve with Teflon felt. The patient's symptoms resolved immediately after the second operation and she has remained symptom free. The authors hypothesize that at least one artery was shifted at the time of her first operation, or immediately thereafter, which resulted in vascular compression of the vagus nerve. To the authors' knowledge, this is the first reported case of a hyperactive gagging response treated with microvascular decompression. The case also illustrates the occurrence of a possibly iatrogenic neurovascular compression syndrome.
Obituary: Henry G. Schwartz, M.D. 1909–1998
Authors: Grubb Robert L.
Published: May 2009

Following a long illness, Henry G. Schwartz, former editor of the Journal of Neurosurgery, died on December 24, 1998 at the age of 89 years.

The author provides an annotated chronology of Dr. Schwartz's life and some highlights of his distinguished career.
The ciliospinal reflex in pentobarbital coma
Authors: Andrefsky John C. , Frank Jeffrey I. , Chyatte Douglas
Published: May 2009

Object. This study was conducted to delineate the ciliospinal reflex (CSR), which is defined as pupillary dilation caused by a noxious stimulus to the face or head. The authors anecdotally observed that patients in a pentobarbital coma have a CSR that can mimic pathological conditions. A pentobarbital coma obscures the results of the neurological examination in patients with potentially life-threatening cerebral edema; pupil size and reactivity are the only readily monitored signs. Any condition that incorrectly suggests evolving intracranial pathological processes can lead to unnecessary clinical actions.

Methods. The authors evaluated six consecutive patients in the neurointensive care unit in whom a pentobarbital coma had been induced, documenting the presence and duration of the CSR. The CSR was always bilateral and symmetrical, manifesting as enlarged (6–8 mm), seemingly nonreactive pupils continuing from 1 to 6 minutes and was usually seen after routine nursing maneuvers. The pupils appeared nonreactive to short flashes of direct light but did react if longer flashes were used.

Conclusions. Recognition of the CSR can potentially lead to reduction of unnecessary transportation and complicating medical interventions in critically neurologically ill patients in whom a pentobarbital coma has been induced.
Differential effects of octreotide treatment and transsphenoidal surgery on growth hormone—binding protein levels in patients with acromegaly
Authors: Hernandez Irma , Soderlund Daniela , Espinosa-de-los-Monteros Ana Laura , Ochoa Raquel , Zarate Arturo , Mercado Moises
Published: May 2009

Object. The high-affinity growth hormone—binding protein (GHBP) represents the extracellular portion of the growth hormone (GH) receptor, and its serum levels are a reflection of the tissue receptor status. Levels of GHBP are decreased in patients with active acromegaly, probably because of downregulation of GH receptors. However, there are no studies of patients with acromegaly in which the effects of medical (that is, administration of somatostatin analogs) and surgical therapy on GHBP levels have been compared. That is the task the authors set out to accomplish in this study.

Methods. The authors studied seven patients in whom acromegaly had been recently diagnosed. They examined these patients at baseline, 2 months after octreotide treatment (subcutaneous administration of 100 µg octreotide three times per day), and 1 month after transsphenoidal surgery. Growth hormone—binding activity was measured, as well as the following biochemical markers of the somatotropic axis: GH suppression induced by oral administration of glucose, insulin-like growth factor-I (IGF-I), and insulin-like growth factor—binding protein-3 (IGFBP3). Although octreotide treatment induced a decrease in the levels of GH, IGF-I, and IGFBP3, as well as an increase in the level of GHBP, these biochemical markers did not reach normal levels. On the other hand, after transsphenoidal surgery, GHBP levels became normal, particularly in those patients in whom serum GH could be suppressed to an undetectable level after glucose loading.

Conclusions. The authors conclude that persistently low GHBP levels in patients with acromegaly are normalized by successful pituitary surgery and correlate well with disease activity.
How should a subarachnoid hemorrhage grading scale be determined? A combinatorial approach based solely on the Glasgow Coma Scale
Authors: Takagi Kiyoshi , Tamura Akira , Nakagomi Tadayoshi , Nakayama Hitoshi , Gotoh Osamu , Kawai Kensuke , Taneda Mamoru , Yasui Nobuyuki , Hadeishi Hiromu , Sano Keiji
Published: May 2009

Object. The purpose of this study was to present a combinatorial approach used to develop a subarachnoid hemorrhage (SAH) grading scale based on the patient's preoperative Glasgow Coma Scale (GCS) score.

Methods. There are 4094 different combinations that can be used to compress the 13 scores of the GCS into two to 12 grades. Break points, the positions in the scale in which two adjacent scores connote a significantly different outcome, are obtained by a direct comparison of the GCS and the Glasgow Outcome Scale (GOS). Guided by the break points, the number of combinations to be considered can be limited. All possible combinations are statistically analyzed with respect to intergrade differences in outcome. Single combinations, with the maximum number of grades having maximum intergrade outcome differences for each corresponding set of adjacent grades, must be selected. The authors verified the validity of this combinatorial approach by retrospectively analyzing 1398 consecutive patients with aneurysmal SAH who underwent surgery within 7 days of the last hemorrhage episode. The patients' GCS scores were assessed just before surgery and their GOS scores were estimated 6 months post-SAH. The combinatorial approach yields only one acceptable grading scale: I (GCS Score 15); II (GCS Scores 11–14); III (GCS Scores 8–10); IV (GCS Scores 4–7); and V (GCS Score 3).

Conclusions. The combinatorial approach, guided by the break points, is so simple and systematic that it can be used again in the future when revision of the grading scale becomes necessary after development of new and effective treatment modalities that improve patients' overall outcome.
Percutaneous transluminal angioplasty and stent placement for recurrent carotid artery stenosis
Authors: Lanzino Giuseppe , Mericle Robert A. , Lopes Demetrius K. , Wakhloo Ajay K. , Guterman Lee R. , Hopkins L. Nelson
Published: May 2009

Object. Treatment consisting of percutaneous transluminal angioplasty (PTA) and stent placement has recently been proposed as an alternative to surgical reexploration in patients with recurrent carotid artery stenosis following endarterectomy. The authors retrospectively reviewed their experience after performing 25 procedures in 21 patients to assess the safety and efficacy of PTA with or without stent placement for carotid artery restenosis.

Methods. The mean interval between endarterectomy and the endovascular procedures was 57 months (range 8–220 months). Seven arteries in five patients were treated by PTA alone (including bilateral procedures in one patient and repeated angioplasty in the same vessel in another). Early suboptimum results and recurrent stenosis in some of these initial cases prompted the authors to combine PTA with stent placement in the treatment of 18 arteries over the past 3 years. No major periprocedural deficits (neurological or cardiac complications) or death occurred. There was one periprocedural transient neurological event, and in one patient a pseudoaneurysm of the femoral artery (at the access site) required surgical repair. In the 16 patients who each underwent at least 6 months of follow-up review, no neurological events ipsilateral to the treated artery had occurred after a mean follow-up period of 27 months (range 6–57 months). Three of five patients who underwent PTA alone developed significant (> 50%) asymptomatic restenoses that required repeated angioplasty in one and PTA with stent placement in two patients. Significant restenosis (55%) was observed in only one of the vessels treated by combined angioplasty and stent placement.

Conclusions. Endovascular PTA and stenting of recurrent carotid artery stenosis is both technically feasible and safe and has a satisfactory midterm patency. This procedure can be considered a viable alternative to surgical reexploration in patients with recurrent carotid artery stenosis.
Delayed neurological deterioration following resection of arteriovenous malformations of the brain
Authors: Morgan Michael K. , Sekhon Lali H. S. , Finfer Simon , Grinnell Verity
Published: May 2009

Object. The aim of this study was to analyze delayed neurological deficits following surgical resection of arteriovenous malformations (AVMs).

Methods. The authors report on a consecutive series of 200 patients with angiographically proven AVMs of the brain that were surgically resected between January 1989 and June 1998. The 30-day mortality rate for patients in this series was 1%, with one death caused by AVM resection and one death attributed to basilar artery aneurysm repair following successful AVM resection. The Spetzler—Martin grading system correlated well with the difficulty of surgery. No permanent incidence of morbidity resulted from resection of Grade I or II AVMs; the percentage of patients with a significant neurological deficit due to resection was 7.8% for those with Grade III lesions and 33.3% for those with Grade IV or V AVMs. However, this grading system did not accurately predict the development of delayed neurological deficits.

Ten patients (5%) developed delayed neurological deficits after recovering from anesthesia and surgery. The delayed deficit was due to hemorrhage in four of the 10 patients and all four had undergone resection of AVMs measuring at least 4 cm in diameter. An increase in blood pressure during the first 8 postoperative days precipitated hemorrhage in these patients. Edema arising as a consequence of propagated venous thrombosis (two patients) was associated with extensive venous drainage networks rather than large AVM niduses. Both hemorrhagic and edematous complications can be included under the umbrella term of “arterial-capillary-venous hypertensive syndrome” to describe the common underlying pathogenesis accurately. An additional four patients developed a delayed deficit as a result of vasospasm. Vasospasm occurred when resection had involved extensive dissection of proximal anterior and middle cerebral arteries; in such cases the incidence of vasospasm was 27%.

Conclusions. On the basis of their analysis of these complications, the authors recommend strict blood pressure control for patients with lesions measuring 4 cm or more in diameter (particularly those with a deep arterial supply). Thromboprophylaxis with aspirin and heparin is prescribed for patients with extensive venous drainage networks, and prophylactic nimodipine therapy and angiographic surveillance for vasospasm are suggested for patients in whom extensive dissection of proximal anterior or middle cerebral arteries has been necessary.
Role of protein tyrosine phosphorylation in erythrocyte lysate—induced intracellular free calcium concentration elevation in cerebral smooth-muscle cells
Authors: Iwabuchi Satoshi , Marton Linda S. , Zhang John H.
Published: May 2009

Object. Tyrosine kinases play an important role in the regulation of systemic vascular smooth-muscle tone. The authors studied the involvement of protein tyrosine kinase activity in erythrocyte lysate—mediated signal transduction in cerebral smooth-muscle cells.

Methods. Tyrosine kinase phosphorylation and intracellular free Ca++ ([Ca++]i) were measured in rat aortic and basilar artery smooth-muscle cells by using Western blot and fura 2-acetoxymethyl ester microfluorimetry. Erythrocyte lysate enhanced tyrosine phosphorylation in cultured rat aortic and basilar smooth-muscle cells and induced a rapid transient and a prolonged plateau phase of [Ca++]i response in rat basilar smooth-muscle cells. The tyrosine kinase inhibitors genistein and tyrphostin A51 (administered at concentrations of 30 or 100 µM) attenuated both phases of erythrocyte lysate—induced [Ca++]i elevation. Erythrocyte lysate was separated into low- (< 10 kD, which contains adenine nucleotides) and high- (> 10 kD, which contains hemoglobin) molecular-weight fractions; these fractions were tested separately in these cells. The low-molecular-weight fraction produced a similar [Ca++]i response to that of erythrocyte lysate and the high-molecular-weight fraction produced a small response. The [Ca++]i responses from both fractions were inhibited by tyrosine kinase inhibitors.

Conclusions. To the authors' knowledge, this is the first report to show that tyrosine phosphorylation may be involved in erythrocyte lysate—induced signal transduction and [Ca++]i responses in cerebral smooth-muscle cells.
Nimodipine-induced survival rate of facial motor neurons following intracranial transection of the facial nerve in the adult rat
Authors: Mattsson Per , Aldskogius Håkan , Svensson Mikael
Published: May 2009

Object. Neuronal survival is an important factor in the achievement of functional restitution after peripheral nerve injuries. Intracranial tumors or trauma may cause patients to exhibit a temporary or permanent facial nerve palsy. Nimodipine, which acts as an antagonist to L-type voltage-gated calcium channels, has been shown to be neuroprotective in various lesion models of the central and peripheral nervous systems. The aim of the present study was to evaluate the effect of nimodipine on motor neuron survival in the facial motor nucleus following intracranial transection of the adult rat facial nerve.

Methods. The facial nerve was cut intracranially in the posterior cranial fossa. Nimodipine was administered orally preoperatively for 3 days and postoperatively for up to 1 month, after which the number of neuronal profiles was quantified. The glial reaction was studied in the facial nucleus for up to 1 month by using immunocytochemical analysis.

There was a significantly larger proportion of surviving motor neurons 1 month postinjury in animals treated with nimodipine (61 ± 6.7%) in comparison with untreated animals (26.8 ± 11.3%). Immunocytochemical analysis showed an increase in the amount of OX42 (microglia), ED1 (macrophages), and anti-glial fibrillary acidic protein (astrocytes) ipsilateral to the nerve injury; however, there was no difference between the two experimental groups of animals 2 to 28 days after surgery.

Conclusions. The authors propose a neuroprotective role for nimodipine, which may be useful as a “cranial nerve protective agent” following insults such as head injury or skull base surgery.
Persistent bilateral hearing loss after shunt placement for hydrocephalus
Authors: Stoeckli Sandro J. , Böhmer Andreas
Published: May 2009

✓ Transient hearing decrease following loss of cerebrospinal fluid (CSF) has been reported in patients undergoing lumbar puncture, spinal anesthesia, myelography, and/or different neurosurgical interventions. The authors present the first well-documented case of a patient with persistent bilateral low-frequency sensorineural hearing loss after shunt placement for hydrocephalus and discuss the possible pathophysiological mechanisms including the role of the cochlear aqueduct. These findings challenge the opinion that hearing decreases after loss of CSF are always transient. The authors provide a suggestion for treatment.
Clinical application of three-dimensional anisotropy contrast magnetic resonance axonography
Authors: Nakada Tsutomu , Nakayama Naoki , Fujii Yukihiko , Kwee Ingrid L.
Published: May 2009

✓ The utility of three-dimensional anisotropy contrast (3DAC) magnetic resonance (MR) axonography, a method sensitive to neuronal fibers and their directionality, was investigated in the clinical setting using a 3-tesla MR imaging system based on a General Electric Signa platform. The study focused on healthy volunteers and patients with common structural central nervous system disorders, namely chronic infarction, brainstem cavernous hemangioma, supratentorial meningioma, and astrocytoma. Three orthogonal anisotropic diffusion-weighted images were first obtained. Three primary colors were each assigned to a diffusion-weighted image, respectively, and the images were subsequently combined into a single-color image in full-color spectrum (3DAC MR axonography image). Fiber-tract definition in the cerebral peduncle of the midbrain of healthy volunteers showed intersubject variation, with two general patterns recognized: dispersed (60% of cases) and compact (40% of cases). Pathological alterations in the fiber tracts were readily identified in cases involving wallerian degeneration of the pyramidal tract, as illustrated in the cases of chronic infarction. Displacement of major tracts, such as the medial lemniscus or corticospinal tract, as well as fiber directionality, was also easily recognized in cases of mass lesions. As an imaging method uniquely capable of providing information regarding axonal connectivity, 3DAC MR axonography appears to have promising potential for routine clinical application.
Trigeminal nerve peripheral branch phenol/glycerol injections for tic douloureux
Authors: Wilkinson Harold A.
Published: May 2009

Object. Trigeminal neuralgia or tic douloureux is a disease affecting older individuals, and thus, office-based “minimally invasive” therapy is inherently attractive. The author sought to determine whether injection of peripheral trigeminal branches with neurolytic solutions offers a simple, less invasive therapy, with low risk for patients with one- or two-division trigeminal neuralgia that is unresponsive to pharmacotherapy.

Methods. This retrospective study focused on a review of case charts from 18 patients treated for tic douloureux. Sixty injections of 10% phenol in glycerol were given to the 18 patients, six of whom had undergone other neurosurgical procedures. The median patient age was 74 years, ranging from 36 to 94 years. There were nine women and nine men. Forty-six injections were administered into the infraorbital nerve in its canal in the midface, 11 percutaneous injections were administered into the mandibular nerve just proximal to the mandibular canal in the ramus of the jaw, and three injections were administered into supraorbital nerves. Eighty-seven percent of injections brought marked or total relief initially. Of those injections that provided initial relief, 37% still provided relief after 1 year and 30% after 2 years, with relief lasting for a median of 9 months after each injection. Most patients whose pain recurred after months of relief requested a repeated procedure, rather than undergo a ganglion nerve block procedure or open surgery. There were no serious complications or dysesthetic pain. Facial sensory loss generally recovered within 6 months and was well tolerated.

Conclusions. Office-based injection of trigeminal branches is a useful technique for neurosurgeons who treat trigeminal neuralgia. It is easily repeated and can provide immediate pain relief of intermediate duration.
Surgery of epilepsy associated with focal lesions in childhood
Authors: Bourgeois Marie , Sainte-Rose Christian , Lellouch-Tubiana Arielle , Malucci Conor , Brunelle Francis , Maixner Wirginia , Cinalli Giuseppe , Pierre-Kahn Alain , Renier Dominique , Zerah Michel , Hirsch Jean-François , Goutières Francoise , Aicardi Jean
Published: May 2009

Object. Surgery in children with epilepsy is a new, evolving field. The important practical issues have been to define strategies for choosing the most suitable candidates and the type and optimal timing of epilepsy surgery. This study was undertaken to elucidate these points.

Methods. To identify the factors that correlated with outcome, the authors analyzed a series of 200 children (aged 1–15 years (mean 8.7 years) who underwent surgery between 1981 and 1996 at the Hôpital Necker—Enfants Malades. In 171 cases (85.5%) the epilepsy was medically refractory and was associated with focal cortical lesions. Surgery consisted of resection of the lesion without specifically attempting to identify and remove the “epileptogenic area.”

In the group of children whose seizures were medically refractory, the mean follow-up period was 5.8 years. According to Engel's classification, 71.3% of these children became seizure free (Class Ia,) whereas 82% were in Class I. A multivariate statistical analysis revealed that among all the factors studied, the success of surgery in a patient in whom there was a good clinical/electroencephalogram/imaging correlation depended on the patient's having undergone a minimally traumatic operation, a complete resection of the lesion, and a short preoperative seizure duration.

After the surgical control of epilepsy, behavior disorders were more improved (31% of all patients) than cognitive function (25%). The patient age at onset, duration and frequency of seizures, intractability of the disease to therapy, and seizure characteristics were correlated with cognitive, behavioral, and academic performance pre- and postoperatively. Multivariate statistical analysis revealed that cognitive dysfunction correlated highly with the duration of epilepsy prior to surgery, whereas behavioral disorders correlated more with seizure frequency.

Conclusions. These data must be taken into account when selecting patients for surgical treatment and when deciding the timing of surgery. Early surgical intervention allows for optimum brain development.
Endovascular treatment of ruptured dissecting aneurysms aimed at occlusion of the dissected site by using Guglielmi detachable coils
Authors: Yamaura Ikuya , Tani Eiichi , Yokota Masayuki , Nakano Atsuhisa , Fukami Masahiro , Kaba Keizo , Matsumoto Tsuyoshi
Published: May 2009

Object. Surgical or endovascular occlusion of the parent artery proximal to an aneurysm has been recommended for treatment of dissecting aneurysms of the intracranial posterior circulation. However, dissecting aneurysms may rupture even after proximal occlusion because distal progression of thrombus is necessary to occlude the dissecting aneurysm completely, and this may be delayed by the presence of retrograde flow. In this article the authors present their experience in treating six patients with ruptured dissecting aneurysms.

Methods. The authors report on six patients with a ruptured dissecting aneurysm in the posterior fossa who were successfully treated by endovascular occlusion of the aneurysm by using Guglielmi detachable coils. The procedure was particularly aimed at occluding the dissected site.

Conclusions. At the present time, endovascular occlusion of the dissected site is a safe, minimally invasive, and reliable treatment for dissecting aneurysms when a test occlusion is tolerated and adequate collateral circulation is present.
A comparison between endovascular and surgical management of basilar artery apex aneurysms
Authors: Gruber David P. , Zimmerman Gary A. , Tomsick Thomas A. , van Loveren Harry R. , Link Michael J. , Tew John M.
Published: May 2009

Object. The goal of this retrospective study was to evaluate endovascular treatment by means of Guglielmi detachable coils (GDCs) compared with surgical management for basilar artery (BA) apex aneurysms.

Methods. Forty-one patients presented with saccular BA apex aneurysms with angiographically definable necks that were judged suitable for either treatment. Of 20 patients who underwent surgery and 21 who underwent GDC embolization, 15 (75%) and 11 (52%), respectively, were treated in the acute phase after subarachnoid hemorrhage (SAH). Twenty-four (92%) of the 26 patients presenting with an SAH had a Hunt and Hess Grade III or better. Fifteen patients with unruptured or ruptured aneurysms more than 14 days post-SAH were treated electively. Patients in the endovascular and surgical treatment groups had aneurysms with comparable dimensions and configurations. Overall, 15 (75%) of the surgical patients and 20 (95%) of the patients in whom GDC embolization was performed had a good outcome (Glasgow Outcome Scale score of 4 or 5). Among those patients treated in the acute stage post-SAH, 11 (73%) of the surgical group and 10 (91%) of the endovascular group did well. Fourteen patients treated electively (93%) had good outcomes. There were two deaths (10%) in the surgical group and none in the endovascular group. Patients treated surgically were hospitalized twice as long and incurred twice the expenses of patients who underwent endovascular treatment (p < 0.001).

Conclusions. Endovascular GDC embolization of select BA apex aneurysms may be a competitive alternative to direct surgical clipping. Long-term follow up is needed to better define the natural history of the endovascularly treated aneurysm and to further evaluate the accuracy of these preliminary results.
Clinical outcome of cotransplantation of peripheral nerve and adrenal medulla in patients with Parkinson's disease
Authors: López-Lozano Juan J. , Bravo Gonzalo , Abascal Javier , Brera Begoña , Millan Isabel , _ _
Published: May 2009

Object. Transplants of adrenal medulla (AM) and fetal ventral mesencephalon (FVM) are currently being tested as therapeutic alternatives in patients with Parkinson's disease (PD). At the Clínica Puerta de Hierro in Madrid, a controlled clinical trial is underway to establish which donor tissue, if any, is the best for open surgical implantation in patients with PD.

Methods. Since 1987, varying degrees of clinical improvement have been achieved in Grade IV and V parkinsonian patients by implanting perfused AM and FVM into the right caudate nucleus. To investigate further whether implantation of different types of donor tissues results in qualitatively and quantitatively different degrees of recovery, four patients with Grade IV or V PD received implants of pre-coincubated autologous AM and intercostal nerve in the caudate nucleus. Four nonsurgically treated patients served as a control group. Three years posttransplantation, longer on phases (46.2% ± 10.4% of the day presurgery to 87.5% ± 10.4% of the day 36 months postsurgery) and improved symptoms in on and off phases persist in all four cases, with reduced dyskinesias (67.1% ± 9.2% of the day in on phases presurgery to 17% ± 13.8% of the day in on phases 36 months postsurgery). Progress appears to be stepwise, starting within weeks of tranplantation and becoming clinically significant in the 2nd and 3rd months (similar to our AM- and sooner than in our FVM-implanted patients), followed by a period of stability and, after a second wave of improvement 12 to 18 months posttransplantation (similar to FVM implants), has continued (87.5 ± 7 points presurgery to 46 ± 5.6 points 36 months postsurgery). In the experimental group, doses of levodopa have been reduced by more than 60% and dopamine agonist use has not resumed. In contrast, there have been no significant clinical changes in the control group.

Conclusions. Implantation of tissue other than fetal tissue can promote a long-term improvement in the clinical symptomatology of seriously disabled parkinsonian patients. This finding is supported by the autopsy report of a patient with PD who had undergone grafting of AM plus peripheral nerve in which it was demonstrated that a large number of tyrosine hydroxylase—positive cells survive 1 year after implantation. In addition, there was a dense network of host dopaminergic fibers around the graft.
Movement disorders following nonfunctional neurosurgery
Authors: Krauss Joachim K. , Borremans Jan J. , Pohle Thomas , Godoy Nelson
Published: May 2009

Object. Knowledge is scarce about movement disorders that follow neurosurgical operations other than functional stereotactic surgery. The cases of 14 patients who suffered from movement disorders secondary to craniocerebral or spinal surgery are analyzed. None of these patients was initially treated by any of the authors.

Methods. Twelve patients underwent surgery for cerebral diseases. Nine of these patients harbored tumors and three patients had neurovascular disorders. Two patients underwent spinal surgery for cervicothoracic ependymoma or for multiple cervical disc herniations. Twelve of the 14 patients had immediate postoperative side effects such as hemiparesis, ataxia, and somnolence. In all but two patients, movement disorders became manifest only after a delay.

Dystonic movement disorders developed in eight patients, unilateral tremors in three patients, unilateral facial myokymia in one patient, and hemichorea—hemiballism in two patients. The mean delay of onset for tremor was 5 weeks and that for dystonic movement disorders was 5.5 months. Movement disorders were transient in three patients; however, they were persistent in 11 patients at a mean follow-up period of 5 years. These movement disorders caused marked persistent disability in four patients. Lesions of the contralateral striatum were identified in patients with dystonic syndromes and lesions of the dentatothalamic outflow in patients with tremors. In three patients who had postoperative basal ganglia lesions after partial removal of astrocytomas, tumor regrowth was later documented. Medical treatment in patients with persistent movement disorders rendered only limited benefit. Two patients improved with botulin injections. In one patient postoperative hemidystonia was alleviated by contralateral thalamotomy.

Conclusions. Dystonic syndromes and tremors are the most common movement disorders that occur after craniocerebral and spinal surgery. Postoperative movement disorders can lead to various degrees of functional disability. The pathoanatomical correlations are similar to those described in other patients with secondary movement disorders.
A brainstem stereotactic atlas in a three-dimensional magnetic resonance imaging navigation system: first experiences with atlas-to-patient registration
Authors: Niemann Klaus , van den Boom Roland , Haeselbarth Katja , Afshar Farhad
Published: May 2009

Object. The authors describe a computer-resident digital representation of a stereotactic atlas of the human brainstem, its semiautomated registration to sagittal fast low—angle shot three-dimensional (3-D) magnetic resonance (MR) imaging data sets in 27 healthy volunteers and 24 neurosurgical patients, and an analysis of the subsequent transforms needed to refine the initial registration.

Methods. Contour drawings from the atlas, which offer the 70th percentile of variation of anatomical structures, were interpolated into an isotropic 3-D representation. Initial atlas-to-patient registration was based on the fastigium/ventricular floor plane reference system. The quality of the fit was evaluated using superimposition of the atlas and MR images. If necessary, the atlas was tailored to the individual anatomy by using additional transforms. On average, the atlas had to be stretched by 2 to 6% in the three directions of space. Scale factors varied over a broad range from −8 to +19% and the benefit of visual interactive control of the atlas-to-patient registration was evident. Analysis of distances within the pons measured in the midsagittal MR imaging slices and the required scale factors revealed significant correlations that may be used to reduce the amount of user interaction in the coregistration substantially. In 70.6% of the cases, the atlas had to be shifted in a cranial direction along the brainstem axis (in 25.5% of cases 3–4 mm, in 45.1% of cases 1–2 mm). This was due to a more caudal position of the fastigium cerebelli on the MR images compared with the atlas.

Conclusions. This observation, in conjunction with the variability of the height of the fourth ventricle in our MR imaging data (range 6.1–15.2 mm, mean 10.1 mm, standard deviation 1.8 mm) calls into question the role of the fastigium cerebelli as an anatomical landmark for localization within the brainstem.
Comparison of tissue impedance measurements with nerve fiber architecture in human telencephalon: value in identification of intact subcortical structures
Authors: Axer Hubertus , Stegelmeyer Jörn , von Keyserlingk Diedrich Graf
Published: May 2009

Object. After establishing the general possibility of real-time impedance monitoring during stereotactic procedures in five postmortem human brains, the authors proceeded to analyze the value of impedance measurements in intact cerebral structures.

Methods. The authors performed impedance measurements at 24 selected points in the brain of a human cadaver and labeled the points by using 1,1′-dilinoleyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI). The texture of the nerve fibers was visualized using confocal laser scanning microscopy, which allowed classification of distinct anatomical regions in the white and gray matter according to their fiber structure (density, direction, structure, and diameter). These regions displayed characteristic differences in impedances according to their fiber structure at frequencies between 8000 and 10,000 Hz. Differences in tissue impedance are not removed, although they are shifted to higher values by fixation with formalin. The reference frequency used in clinical environments (50,000 Hz) is not useful for distinct localization purposes. Finally, the orientation of the electrode in relation to the tissue is a crucial factor.

Conclusions. It should be possible to draw conclusions about the correct position of the stereotactic needle on the basis of the proposed location, the texture of the fibers (orientation and density), and the orientation of the electrode.
Biodegradable semirigid plate and miniscrew fixation compared with rigid titanium fixation in experimental calvarial osteotomy
Authors: Peltoniemi Hilkka H. , Tulamo Riitta-Mari , Toivonen Terttu , Hallikainen Dorrit , Törmälä Pertti , Waris Timo
Published: May 2009

Object. To determine the biocompatibility and suitability of resorbable plates and miniscrews, consolidation of symmetrical, bilateral frontal bone craniotomies that had been closed using various methods was studied in 20 growing lambs.

Methods. Bone fixation with a flexible, punched polylactide plate and four slowly degradable, self-reinforced polylevolactide (SR-PLLA) or rapidly degradable, self-reinforced polyglycolide (SR-PGA) miniscrews (10 animals in each group) was compared intraindividually with rigid fixation by using a titanium miniplate and four miniscrews. Plain x-ray films, magnetic resonance images, histological studies, and histomorphometric studies were obtained at 4 to 104 weeks.

Conclusions. No dislocation, instability, clinical foreign body reactions, infections, or loss of fixation were observed. Bone consolidation of the 2.35-mm-wide craniotomy lines was incomplete; connective tissue—filled defects through the bone were observed in 13 of 28 lines at 26 to 52 weeks. Statistical analyses based on histomorphometric studies showed no difference in consolidation with SR-PLLA miniscrew and titanium plate/screw fixation or between the two resorbable fixation methods. Fixation with rapidly degradable SR-PGA miniscrews resulted in less effective consolidation than on the contralateral titanium-treated side (p < 0.05), but the bone segment was thicker (p < 0.005). The SR-PGA miniscrews had disappeared by 6 weeks, the polyactide plate by 104 weeks, and the SR-PLLA miniscrews had been mostly resorbed at 104 weeks. Passive translocation of the titanium plates and screws into the bone tissue was seen at 52 and 104 weeks. In rapidly growing lamb frontal bone, comparable consolidation results, without complications, can be achieved with semirigid resorbable fixation compared with rigid metallic fixation.
Polymorphism of the endoglin gene in patients with intracranial saccular aneurysms
Authors: Takenaka Katsunobu , Sakai Hideki , Yamakawa Hiroyasu , Yoshimura Shin-ichi , Kumagai Morio , Yamakawa Haruki , Nakashima Shigeru , Nozawa Yoshinori , Sakai Noboru
Published: May 2009

Object. Endoglin, a transforming growth factor β—binding protein, is a glycoprotein expressed on the surface of human vascular endothelial cells. Mutations of this gene are responsible for hereditary hemorrhagic telangiectasis and are associated with sporadic intracerebral hemorrhage as a risk factor. The purpose of this study was to examine the polymorphism of this gene in patients with intracranial aneurysms.

Methods. The authors identified the mutations and insertion polymorphism around exon 7 of the endoglin gene in 82 patients with intracranial saccular aneurysms (aneurysm group) and 114 control volunteers (control group).

A 6-base insertion (GGGGGA) was found in intron 7 at 26 bases beyond the 3′ end of exon 7. The homozygous insertion of intron 7 of the gene was present in 20.7% of the aneurysm group compared with 6.1% of the control group (χ2 = 9.837, p = 0.0073). The insertion allele frequency was significantly higher in the aneurysm group (67 [40.8%] of 164) than that in the control group (63 [27.6%] of 228) (χ2 = 7.48, p = 0.0062). The most notable clinical characteristic of the 17 patients with homozygous insertion in the aneurysm group was the relatively high percentage of patients with hypertension and of those with multiple aneurysms.

Conclusions. The data provide evidence of an association between aneurysm development and a polymorphism at a genetic variant of endoglin in patients with these lesions.
The hPMS2 exon 5 mutation and malignant glioma
Authors: Taylor Michael D. , Perry James , Ƶlatescu Magdalena C. , Stemmer-Rachamimov Anat O. , Ang L. C. , Ino Yasushi , Schwartz Michael , Becker Laurence E. , Louis David N. , Cairncross J. Gregory
Published: May 2009

✓ Patients with Turcot syndrome (TS) are predisposed to colon tumors and primary brain tumors, typically glioblastomas or medulloblastomas. The authors describe a patient with TS featuring a known germline mutation of exon 5 of the hPMS2 mismatch repair gene who developed two metachronous glioblastomas, both with distinct oligodendroglial features. Molecular genetic analysis revealed allelic loss of chromosome 19q in the patient's second tumor but no allelic loss of chromosome 1p. Prominent microsatellite instability was also found in this tumor, consistent with a germline mismatch repair defect. Because this patient had an unusual underlying condition and his tumor had a unique histological appearance for TS, it was hypothesized that this genetic defect may predispose to malignant gliomas with oligodendroglial features. The authors therefore evaluated whether sporadic glioblastomas and oligodendrogliomas undergo mutations of this region of the hPMS2 gene. However, single-strand conformation polymorphism analysis of hPMS2 exon 5 failed to reveal mutations in 20 sporadic glioblastomas and 16 sporadic oligodendroglial gliomas. Thus, although it is possible that the germline hPMS2 exon 5 mutation may predispose to glioblastomas with an oligodendroglial component, the same genetic defect is not commonly involved in sporadic oligodendrogliomas or glioblastomas.
Transumbilical embolization of a congenital dural arteriovenous fistula at the torcular herophili in a neonate
Authors: Komiyama Masaki , Nishikawa Misao , Kitano Shouhei , Sakamoto Hiroaki , Miyagi Nobuhiro , Kusuda Satoshi , Sugimoto Hisakazu
Published: May 2009

✓ A neonate, in whom a congenital cerebral vascular anomaly had been diagnosed prenatally, exhibited progressive high-output congestive heart failure soon after birth. Cerebral angiography revealed a congenital dural arteriovenous fistula (AVF) with a huge dural lake located at the torcular herophili. In addition to the meningeal blood supply, an unusual pial blood supply from all cerebellar arteries was observed to feed the fistula. The patient was treated by repeated transarterial and transvenous embolization through the umbilical venous route. To the authors' knowledge, neither the existence of a congenital dural AVF at the torcular herophili presenting with an enormous pial blood supply or the technique of transumbilical venous intervention has been reported in the literature.