bluuebunny/crossref_metadata_2025 huggingface dataset:
Abnormal cerebral vasodilation in aneurysmal subarachnoid hemorrhage: use of serial 133Xe cerebral blood flow measurement plus acetazolamide to assess cerebral vasospasm
Authors: Dinh Yves Roger Tran , Lot Guillaume , Benrabah Rabah , Baroudy Oussama , Cophignon Jean , Seylaz Jacques
Published: May 2009

✓ A patient with cerebral vasospasm following subarachnoid hemorrhage (SAH) was investigated by serial measurement of cerebral blood flow (CBF) using the xenon-133 emission tomography method. The CBF was measured before and after acetazolamide injection. On Day 2 after SAH, there was early local hyperperfusion in the middle cerebral artery (MCA) territory, ipsilateral to the left posterior communicating artery aneurysm. The regional CBF of this arterial territory decreased slightly after acetazolamide injection, probably because of vasoplegia and the “steal” phenomenon, and thus surgery was delayed. A right hemiplegia with aphasia and disturbed consciousness occurred 4 days later (on Day 6 after SAH) due to arterial vasospasm, despite treatment with a calcium-channel blocker. The initial hyperemia of the left MCA territory was followed by ischemia. The vasodilation induced by acetazolamide administration was significantly subnormal until Day 13, at which time CBF and vasoreactivity amplitude returned to normal and the patient's clinical condition improved. Surgery on Day 14 and outcome were without complication. It is concluded that serial CBF measurements plus acetazolamide injection are useful for monitoring the development of cerebral vasospasm to determine the most appropriate time for aneurysm surgery.
Intracanalicular acoustic neuroma: early surgery for preservation of hearing
Authors: Haines Stephen J. , Levine Samuel C.
Published: May 2009

✓ Diagnosis of very small acoustic neuromas has become much more common since the advent of magnetic resonance imaging. Many of the patients so diagnosed have minimal unilateral hearing loss as their only symptom. Because limited information is available on the natural history and prognosis of these lesions, the choice of treatment is controversial. The authors review their recent experience with the surgical treatment of intracanalicular acoustic neuroma.

The records of 14 consecutive patients with intracanalicular acoustic neuroma were reviewed with respect to type of presentation, pre- and postoperative facial and auditory nerve function, surgical approach, and complications. Detailed results for patients operated on to preserve hearing are presented. Presenting symptoms were nearly equally divided among diminished hearing, vertigo, and tinnitus. Eleven of the 14 patients had serviceable hearing preoperatively and nine (82%) remained in this condition postoperatively. Facial nerve function was unchanged by operation in 12 patients. Seven operations were performed through the middle fossa, five through the posterior fossa, and two by the translabyrinthine approach.

The probability of preserving hearing during surgical excision of intracanalicular acoustic neuroma in patients with serviceable hearing exceeds 80%. Given the relative infrequency of serious complications and the likelihood of progressive hearing loss in the untreated patient, excision of such small tumors shortly after diagnosis may offer the best chance of long-term hearing preservation.
Spinal malignant nerve-sheath tumor or cellular schwannoma? A striking difference in prognosis
Authors: Seppälä Matti T. , Haltia Matti J. J.
Published: May 2009

✓ Cellular schwannoma, a recently delineated entity, has a histological appearance mimicking that of malignant neoplasms. The aim of this study was to determine the outcome for patients treated for a spinal cellular schwannoma or malignant nerve-sheath tumor. A histological re-examination was conducted of 283 spinal tumors, considered to originate from a nerve root, that were treated in the Department of Neurosurgery between 1953 and 1985. After re-examination, 50 of these were determined to be other tumors or nonneoplastic lesions. The review yielded eight cellular schwannomas and six malignant nerve-sheath tumors out of 233 of nerve-sheath origin. Immunohistochemical staining with a commercially available polyclonal antibody against S-100 protein was positive in all cases of cellular schwannoma, but negative for the malignant tumors. Clinical outcome was favorable for patients with cellular schwannomas, but uniformly poor for those with the malignant tumors.
The role of photodynamic therapy in posterior fossa brain tumors
Authors: Whelan Harry T. , Schmidt Meic H. , Segura Annette D. , McAuliffe Timothy L. , Bajic Dawn M. , Murray Kevin J. , Moulder John E. , Strother Douglas R. , Thomas James P. , Meyer Glenn A.
Published: May 2009

✓ Photodynamic therapy was studied in dogs with and without posterior fossa glioblastomas. This mode of therapy consisted of intravenous administration of Photofrin-II at doses ranging from 0.75 to 4 mg/kg 24 hours prior to laser light irradiation in the posterior fossa. Tissue levels of Photofrin-II were four times greater in the tumor than in the surrounding normal brain. Irradiation was performed using 1 hour of 500 mW laser light at a wavelength of 630 nm delivered through a fiberoptic catheter directly into the tumor bed via a burr hole. All animals receiving a high dose (4 or 2 mg/kg) of Photofrin-II developed serious brain-stem neurotoxicity resulting in death or significant residual neurological deficits. A lower dose (0.75 mg/kg) of Photofrin-II produced tumor kill without significant permanent brain-stem toxicity in either the control animals or the animals with cerebellar brain tumors receiving photodynamic therapy.
Magnetoencephalographic localization of a language processing cortical area adjacent to a cerebral arteriovenous malformation
Authors: Martin Neil A. , Beatty Jackson , Johnson Russell A. , Collaer Marcia L. , Viñuela Fernando , Becker Donald P. , Nuwer Marc R.
Published: May 2009

✓ In order to accurately estimate the risk of surgery for dominant perisylvian arteriovenous malformations, the topographical relationship of the lesion to language cortex must be determined. A case is presented in which a magnetoencephalographic (MEG) study was used to map preoperatively and noninvasively an intracortical source of speech-receptive cortex in a 25-year-old right-handed man with a dominant left temporal lobe arteriovenous malformation. The speech-evoked magnetic field was analyzed at 36 positions over the left hemisphere in response to presentations of the consonant-vowel syllables “da” and “ga.” A topographical map of the magnetic component evoked at 110 msec after stimulus onset, which was negative going to the vertex in concurrent electrical recordings, was congruent with a superficial cortical neuronal current source. This source was displaced from that usually observed in normal individuals to tonal or click stimuli, being superior to the probable location of auditory cortex, and superior and anterior to the probable location of Wernicke's area as conventionally described. The MEG results were in accord with the determination of position of a language-processing cortical area as assessed by direct electrical stimulation of the cortex during surgery under local anesthesia, and by superselective Amytal (amobarbital) injection during angiography. The MEG recordings and exposed brain stimulation sites were coordinated by cranial measurements, skull x-ray landmarks, and angiographic anatomy. Investigations such as this, which compare MEG findings with those from established clinical procedures, are an essential step in determining the physiological and anatomical utility of magnetoencephalography for noninvasive clinical functional localization.
Intracranial vertebral arteriovenous fistula
Authors: Halliday Andrea L. , Ogilvy Christopher S. , Crowell Robert M.
Published: May 2009

✓ True intracranial arteriovenous fistulas are rare. The authors report a case of a direct fistula between the intracranial portion of the vertebral artery and the lateral medullary venous system. The patient initially presented with a subarachnoid hemorrhage. An open surgical approach with clip obliteration of the lesion was used. The anatomy of this lesion and its surgical management are described.
True anatomical compartmentalization of the cavernous sinus in a patient with bilateral cavernous dural arteriovenous fistulae
Authors: Chaloupka John C. , Goller David , Goldberg Robert A. , Duckwiler Gary R. , Martin Neil A. , Viñuela Fernando
Published: May 2009

✓ An unusual case of complete anatomical compartmentalization of the cavernous sinus in a patient with bilateral Type D cavernous dural arteriovenous fistulae is described. This anatomical anomaly isolated the anterior cavernous sinus and orbital venous system, which was primarily responsible for the patient's clinical presentation. The compartmentalization of the cavernous sinus also limited options for definitive endovascular therapy to a transvenous approach via the superior ophthalmic vein.
Primary (granulomatous) angiitis of the central nervous system with multiple aneurysms of spinal arteries
Authors: Yoong Meow F. , Blumbergs Peter C. , Brian North J.
Published: May 2009

✓ A 55-year-old woman with primary (granulomatous) angiitis of the central nervous system in association with non-Hodgkin's lymphoma (mucosa-associated lymphoid tissue type) presented with an acute spinal subdural hemorrhage secondary to rupture of one of several fusiform inflammatory aneurysms of the spinal cord radicular arteries. The literature on hemorrhagic complications, aneurysms, and spinal cord involvement in granulomatous angiitis is reviewed. Recognition of granulomatous angiitis is important, as the condition may be responsive to immunosuppressive therapy.
Supraorbital craniotomy by fracture of the anterior orbital roof
Authors: Delashaw Johnny B. , Jane John A. , Kassell Neal F. , Luce Craig
Published: May 2009

✓ The authors describe a new and rapid method to safely perform a supraorbital craniotomy. This technique can be used when tumor does not invade the orbital roof. Previous descriptions of the supraorbital craniotomy involved exposure of the frontal sinus by removing its anterior wall and using the Gigli saw to separate the orbital roof. This new approach avoids removal of the anterior frontal sinus wall and separates the supraorbital bone flap from the calvaria by fracturing the anterior orbital roof forward. In addition, a method for harvesting a laterally based pericranium and muscle pedicle that contains a section of contralateral temporalis muscle is described. This vascularized pedicle can be used for repair of cerebrospinal fluid leaks or bone defects along the anterior fossa floor and orbit.
Neurosurgeon as innovator: William V. Cone (1897–1959)
Authors: Preul Mark C. , Stratford Joseph , Bertrand Gilles , Feindel William
Published: May 2009

✓ Neurosurgeons are well known for being productive researchers and innovators. Few, however, have possessed the prolific ingenuity of William Cone. In 1934, he and Wilder Penfield were cofounders of the Montreal Neurological Institute where, until 1959, he filled the twin roles of neurosurgeon-in-chief and neuropathologist.

Because he did not find writing easy, many of his technical inventions and refinements remained unpublished. His numerous innovations included the extensive use of twist-drill technique for biopsy, drainage for subdural hematoma and cerebral abscess, and ventriculography. In the mid-1940's, he developed power tools driven by nitrogen that led to the modern, universally used air-driven tool systems. He had a special interest in the treatment of spinal dysfunction, for which he invented the Cone-Barton skull-traction tongs along with the Cone spinal operating table. He also devised operative procedures for vertebral fracture-dislocation and craniospinal anomalies. For the maintenance of muscle tone in the paralyzed bladder, he constructed a tidal drainage system. He introduced and popularized ventriculoperitoneal shunting techniques and carried out some of the earliest experimental trials to treat brain infections with sulphonamide and antibiotic drugs. He designed his own set of surgical suction devices, bone rongeurs, and a personal suction “air-conditioning” system for each surgeon. He had a keen early interest in intracranial tumors, and also demonstrated on monkeys how subdural mass lesions caused pupillary dilation and mesial temporal lobe damage due to cerebral compression. His work for the military during World War II on effects of altitude on brain pressure remained classified for many years. The first clipping and excision of an intracranial aneurysm is attributed to Cone.

Although Penfield was known as “the Chief,” Cone was referred to as “the Boss.” His fervent dedication to provide total care to his patients was expressed in round-the-clock vigils; he did not separate “nursing” from “surgical” care. Ultimately, Cone's driving passion for perfection led in part to his tragic death. His accomplishments, inventions, and his example as teacher and physician have become part of neurosurgery's collective legacy.
Therapeutic effects of local delivery of dexamethasone on experimental brain tumors and peritumoral brain edema
Authors: Ikeda Yukio , Carson Benjamin S. , Lauer Jeremy A. , Long Donlin M.
Published: May 2009

✓ To determine if dexamethasone administered by osmotic pump directly to brain tumors would control peritumoral edema and at the same time suppress tumor growth and prolong survival, the authors studied experimental brain tumors produced in 102 rabbits by implanting VX2 carcinoma cells. Of these, 58 animals were separated into three treatment groups: Group 1 included 15 untreated rabbits; Group 2 included 18 rabbits treated with systemic dexamethasone (4 mg/kg/day); and Group 3 included 25 rabbits treated with local dexamethasone (0.24 mg/day) delivered by osmotic pump. Systemic or local dexamethasone was administered from Day 3 or Day 7 after tumor implantation, and animals were sacrificed on Day 13. A survival study was performed with 44 rabbits separated into the same treatment groups, beginning drug delivery on Day 7. Brain water content in the white matter of sacrificed animals was measured by the specific gravity method. The length and width of the brain tumors in all animals were measured and the tumor volume estimated. Findings showed that systemic and local dexamethasone administered from Day 3 or Day 7 was associated with a significant (5% level) inhibition of tumor volume as well as a mean reduction of brain edema in most tested sites. Systemic and local dexamethasone therapy also resulted in a significant (5% level) increase in survival time relative to the untreated group. These short-term results suggest that locally delivered dexamethasone may constitute a clinically important therapeutic modality.
Dissociation of cerebral blood flow, glucose metabolism, and electrical activity in pediatric brain death
Authors: Medlock Michael D. , Hanigan William C. , Cruse Robert P.
Published: May 2009

✓ A 2-month-old infant demonstrated clinical brain death 48 hours after suffering a closed head injury accompanied by cardiac arrest. Two nuclear cerebral blood flow (CBF) studies demonstrated normal perfusion. On the 11th day following injury, cerebral electrical activity ceased and a normal glucose metabolic gradient between gray and white matter was documented on positron emission tomography. Autopsy revealed widespread necrosis with mononuclear cell infiltrates throughout all cerebral cortical layers.

Nine children have previously been described with clinical brain death, electrocerebral silence, and evidence of CBF by radionuclide scan. The dissociation between cerebral electrical activity and blood flow may be explained by an increase in cranial volume allowed by the expansile neonatal skull, preventing both intracranial hypertension and a reduction in perfusion pressure. The persistence of glucose metabolism may be associated with the presence of inflammatory microglial cells in the ischemic cortex. The authors conclude that persistence of CBF and glucose metabolism in brain-dead children may not indicate neuronal survival. If repeated neurological examinations with or without electroencephalography support the diagnosis of brain death, the presence of CBF and glucose metabolism should not alter this conclusion.
Increased mitotic activity as a negative prognostic indicator in pleomorphic xanthoastrocytoma
Authors: Macaulay Robert J. B. , Jay Venita , Hoffman Harold J. , Becker Laurence E.
Published: May 2009

✓ Pleomorphic xanthoastrocytoma is a recently characterized neoplasm with a favorable prognosis despite aggressive histological features. The authors report a case of pleomorphic xanthoastrocytoma that recurred 4 years after complete gross resection. The original tumor exhibited histological features characteristic of this neoplasm, but up to 4 mitoses/10 high-power fields were present focally. The recurrent tumor contained small foci of classical pleomorphic xanthoastrocytoma, but consisted predominantly of glioblastoma multiforme. Transitional zones contained nests of glial fibrillary acidic protein (GFAP)-immunopositive cells surrounded by delicate collagenous and reticulin-rich septa. Electron microscopy of the transitional zone showed continuous basal lamina investing cells containing bundles of intermediate filaments. These were GFAP-positive by immunogold electron microscopy, confirming the astrocytic nature of pleomorphic xanthoastrocytoma. This example illustrates the capacity of this tumor to evolve into glioblastoma. The indolent clinical behavior of most pleomorphic xanthoastrocytomas is evident from a literature review, which confirms the prolonged survival of many patients after onset of symptoms. Completeness of excision, subjectively assessed at surgery, did not influence the risk of recurrence or survival up to 10 years after initial resection. Postoperative radiotherapy did not improve survival, but may reduce the probability of recurrence; more studies are needed to corroborate this finding.

The data compiled herein support the designation of pleomorphic xanthoastrocytoma as a distinct astrocytic neoplasm with a favorable prognosis. An increased mitotic rate has not previously been correlated with a worse outcome, and should not be used to exclude this diagnosis. However, anaplastic transformation of pleomorphic xanthoastrocytoma confers a much worse prognosis, and this case suggests that increased mitotic activity may be a negative prognostic indicator since it may herald subsequent anaplastic transformation.
Split-calvaria osteoplastic rotational flap for anterior fossa floor repair after tumor excision
Authors: Kantrowitz Allen B. , Hall Craig , Moser Franklin , Spallone Aldo , Feghali Joseph G.
Published: May 2009

✓ A split-calvaria osteoplastic rotational flap to repair the anterior fossa floor after tumor excision was devised and tested clinically. At surgery, the flap is outlined between the glabella and the vertex. After the pericranium between the glabella and the flap's anterior pole is elevated to form its pedicle, a full-thickness craniotomy is performed to expose the diploic aspect of the bone graft donor site (when the graft is relatively wide, bifrontal craniotomies may be advantageous). The diploic space is splitin situ, taking care to protect the pedicle and its attachments to the osseous segment. Linear osteotomies in the outer table are created to mobilize the flap. With the flap rotated frontally, the craniotomy is completed. After tumor extirpation, the margins of the osseous segment of the flap are shaped to conform to the defect of the anterior fossa floor. Transverse osteotomies are performed so that the graft's convex curve conforms to that of the anterior fossa floor. The flap is then rotated into position.

Follow-up evaluation in two patients at 22 and 30 months demonstrated bone integrity of the anterior fossa floor with graft preservation. Transient postoperative cerebrospinal fluid (CSF) rhinorrhea, which occurred in Case 1, was avoided in Case 2 by placing the osseous segment of the graft coplanar with the bone floor of the fossa. Neither patient had late meningitis or CSF rhinorrhea.

The split-calvaria osteoplastic rotational flap may represent an advance toward the ideal reconstruction of the anterior cranial fossa floor.
Release of β-endorphin and methionine-enkephalin into cerebrospinal fluid during deep brain stimulation for chronic pain
Authors: Young Ronald F. , Bach Flemming W. , Norman Alan S. Van , Yaksh Tony L.
Published: May 2009

✓ The authors systematically studied the release of the endogenous opioid peptides β-endorphin and methionine (met)-enkephalin into the cerebrospinal fluid (CSF) during deep brain stimulation in patients suffering from otherwise intractable chronic pain. Nine patients were included in the study; six had stimulation electrodes placed in both the periventricular gray matter (PVG) and the thalamic nucleus ventralis posterolateralis (VLP) and three in the PVG only. Immunoreactivity of β-endorphin and met-enkephalin (β-EPir and MEir, respectively) was measured by radioimmunoassays in ventricular and lumbar CSF samples obtained before, during, and after stimulation. Prestimulation concentrations of β-EPir and MEir were lower in ventricular than in lumbar CSF (6.6 ± 0.5 vs. 13.7 ± 1.0 pmol/liter, p = 0.0001, for β-EPir; 33.6 ± 5.1 vs. 48.3 ± 3.2 pmol/liter, p < 0.05, for MEir). Ventricular CSF concentrations of both β-EPir and MEir increased significantly during PVG stimulation, whereas VPL stimulation was without effect. No changes were seen in lumbar CSF levels of the peptides during stimulation in either site. A significant inverse relationship was found between the “during:before stimulation” ratios of visual analog scale ratings and β-EPir levels during PVG stimulation. The β-EPir and MEir concentration during:before stimulation ratios were positively correlated, whereas no correlation was present in prestimulation samples from ventricular or lumbar CSF. High-performance liquid chromatography of ventricular CSF pools obtained during PVG stimulation revealed that major portions of β-EPir and MEir eluted as synthetic β-endorphin and met-enkephalin, respectively, thus documenting the release of β-endorphin and met-enkephalin into ventricular CSF during PVG stimulation. The finding of a direct relationship between β-EPir release and pain alleviation may suggest a role for β-endorphin in the analgesic mechanism of PVG stimulation.
Central nervous system gangliogliomas
Authors: Miller Douglas C. , Lang Frederick F. , Epstein Fred J.
Published: May 2009

Histopathological features that suggest the diagnosis of ganglioglioma require, in most cases, confirmation by special stains to distinguish these tumors from other gliomas. For this purpose, immunostaining for synaptophysin, which has previously been shown to selectively label the cell surface of neoplastic ganglion cells, was used to retrospectively examine glioma tumor specimens. Sixty-three cases of ganglioglioma were identified. The files of the Division of Neuropathology of New York University Medical Center contained 45 tumors that had been diagnosed as ganglioglioma, of which 42 were verified by synaptophysin; three cases were reclassified, two as astrocytomas and one as a gangliocytic paraganglioma. Thus, a tumor identified as ganglioglioma based on other criteria was likely to be a ganglioglioma. The other 21 cases of gangliogliomas were originally diagnosed as astrocytoma or mixed glioma, but were shown by synaptophysin staining to be gangliogliomas. In some cases the ultimate diagnosis was obtained after radical surgery provided relatively abundant amounts of tissue, thereby limiting sampling errors, in contrast to the biopsies from which the original diagnoses were made.

Histopathological review of these cases demonstrated that four features represent important clues to the correct diagnosis: 1) clusters of large cells potentially representing neurons (without such cells the tumor cannot be classified as a ganglioglioma); 2) no perineuronal clustering of the glial cells around the alleged neoplastic neurons; 3) fibrosis (desmoplasia); and 4) calcification. Binucleate neurons, previously suggested to be common in gangliogliomas, were not frequently found in this series, and lymphocytic infiltrates, while common, are so often found in other tumors that they gave no specific hint that any single neoplasm was a ganglioglioma. The glial elements were astrocytic in all cases, except that one tumor also had oligodendroglial and ependymal patterns. Four tumors also had small mature neurons, as seen in neurocytomas. Cells from one tumor were successfully grown in short-term tissue culture; the culture contained large dividing neurons with synaptophysin immunoreactivity as well as smaller dividing cells, demonstrating that the neuronal cells are a proliferating element in gangliogliomas.
Effects of dorsal rhizotomy on depressor response to spinal cord stimulation mediated by endogenous calcitonin gene-related peptide in the pithed rat
Authors: Nuki Yoshitsugu , Kawasaki Hiromu , Taguchi Toshifumi , Takasaki Koichiro , Wada Akihiko
Published: May 2009

✓ The effects of acute and chronic dorsal rhizotomy on vasodilation induced by spinal cord stimulation were investigated in the pithed ratin vivo. Pithed rats were treated intravenously with hexamethonium (2 mg/kg/min) to block autonomic outflow, and mean arterial blood pressure was maintained at approximately 100 mm Hg with methoxamine (10 to 15 µg/kg/min). Electrical stimulation (2 or 4 Hz, 10 V, 1 msec) of the lower thoracic spinal cord (T9–12) via the pithing rod caused a frequency-dependent depressor response without a change in heart rate. The depressor response to spinal cord stimulation was inhibited by the intravenous administration of human calcitonin gene-related peptide (CGRP) [8–37] (60 nmol/kg/min) or tetrodotoxin (100 µg/kg). In the pithed rat with acute or chronic bilateral dorsal root rhizotomy at lower thoracic levels (T8–12), spinal cord stimulation at 2 and 4 Hz caused no depressor response. These results suggest that the depressor response to spinal cord stimulation is mediated by endogenous CGRP, which is released from CGRP-containing nerves. The present results also suggest an outflow of CGRP-containing nerves from the spinal cord via the dorsal roots.
Dose-response study of the pathological effects of chronically applied direct current stimulation on the normal rat spinal cord
Authors: Hurlbert R. John , Tator Charles H. , Theriault Elizabeth
Published: May 2009

✓ Electrical stimulation of the mammalian central nervous system (CNS) can result in extensive destruction of tissue unless applied within specific stimulation parameters. Classically, unbalanced or monopolar currents have been avoided in order to minimize these harmful effects. However, direct current (DC) fields have recently been proposed for the treatment of spinal cord injury. Until now, no rigorous analysis has been made of the safety of these fields in the mammalian CNS. The purpose of this study was to determine the amount of chronically applied DC current that can be tolerated by the normal rodent spinal cord stimulated with metal disc electrodes.

Thirty-five normal rats underwent implantation of DC stimulating devices and were allowed to recover for a period of 2 to 12 weeks. The stimulators delivered constant currents of 0 to 50 µA through two disc-shaped platinum/iridium electrodes positioned extradurally at the C-7 and T-3 levels. Following sacrifice of the animals, serial 8-µm cross sections of the spinal cord at the electrode sites were examined microscopically. Evidence of demyelination presumed due to the physical presence of the rostral electrode was seen in animals from most groups including control animals. Pathological changes directly attributable to the applied fields were seen with current as low as 3 µA. It was concluded that DC's of 3 µA or more are harmful to the mammalian CNS with this method of stimulation. In addition, the data suggest that the maximum current density tolerated by the rodent spinal cord is in the order of 75 µA/sq cm. These findings have important implications for the use of chronic DC stimulation in the mammalian CNS.
Atlas hypoplasia as a cause of high cervical myelopathy
Authors: Komatsu Yoji , Shibata Tomoyuki , Yasuda Susumu , Ono Yukio , Nose Tadao
Published: May 2009

✓ A high cervical myelopathy due to atlas hypoplasia is described in a 56-year-old man; the condition caused marked segmental compression of the spinal cord. A remarkable neurological recovery followed decompressive laminectomy of the atlas and adjacent regions. The authors discuss the embryology and etiology of this anomaly.
Neurogenic hypertension related to basilar impression
Authors: Dickinson Lawrence D. , Papadopoulos Stephen M. , Hoff Julian T.
Published: May 2009

✓ The authors report the resolution of essential hypertension following transoral odontoidectomy and medullary decompression in a 39-year-old woman with basilar invagination. Current understanding of central regulation of the cardiovascular system is discussed and the pertinent neuroanatomy illustrated. Experimental and clinical evidence supporting the role of neurogenic mechanisms in the pathogenesis of hypertension is reviewed.
Microvascular sling decompression for trigeminal neuralgia secondary to ectatic vertebrobasilar compression
Authors: Stone James L. , Lichtor Terry , Crowell Robert M.
Published: May 2009

✓ A patient with trigeminal neuralgia caused by a tortuous and ectatic vertebrobasilar artery is presented. He was treated with microvascular decompression using a fine silicone sling sutured to the dura over the petrous pyramid. The technical details are described.
Temporal muscle microfixation in pterional craniotomies
Authors: Zager Eric L. , Del Vecchio Daniel A. , Bartlett Scott P.
Published: May 2009

✓ Temporal muscle asymmetry is a common sequela of pterional craniotomies. The authors describe a simple technique of restoring the temporal muscle to its origin by microscrew fixation. This technique provides reliable preservation of temporal muscle bulk and function with little additional operating time and no compromise of operative exposure.
Labeled Schwann cell transplants versus sural nerve grafts in nerve repair
Authors: Kim Daniel H. , Connolly Sean E. , Kline David G. , Voorhies Rand M. , Smith Andrea , Powell Mary , Yoes Tracy , Daniloff Joanne K.
Published: May 2009

✓ This study evaluated the ability of Schwann cell transplants to enhance the recovery of function in injured nerves and compared the results to those produced by sural nerve grafts. Schwann cells were isolated from sciatic nerves, prelabeled with gold fluorescent dye admixed with collagen gel, and placed in resorbable collagen tubes. Twenty-four adult rats underwent severing of the bilateral sciatic nerves, with a 10-mm gap between the nerve stumps. The rats were then divided into two groups. A collagen tube with implanted Schwann cells was implanted in one leg of the Group I rats, and the contralateral leg served as a control and was repaired with a collagen tube filled with collagen gel only. The Group II animals received conduits packed with labeled Schwann cells in one leg to bridge the 10-mm gap; the contralateral leg was repaired with an autogenous sural nerve graft. Recovery of function was assessed physiologically and morphologically.

Nerve conduction velocity and nerve action potential amplitude measurements showed that the Schwann cell implants induced return of function comparable to that of the sural nerve grafts. Morphological assessments of myelination suggested a tendency toward greater numbers of myelinated axons in Schwann cell implants than in sural nerve grafts. Anatomical analyses of gold fluorescent dye showed both high viability of prelabeled Schwann cells at 120 days after transplantation and migration as far as 30 mm away from the implant site.
The role of active smooth-muscle contraction in the occurrence of chronic vasospasm in the canine two-hemorrhage model
Authors: Matsui Toru , Kaizu Hiroyuki , Iron Shoichi , Asano Takao
Published: May 2009

✓ To evaluate the pathogenetic role of alterations in the physical properties of the arterial wall (the passive component) and of active smooth-muscle contraction (the active component) in the occurrence of chronic vasospasm, the temporal profiles of these events were examined using the canine “two-hemorrhage” model. In thein vivostudy, the basilar artery was exposed via the transclival approach on Day 0, 2, 4, 7, or 14. Nicardipine, followed by the protein kinase C inhibitor H-7, then papaverine were administered in a cumulative fashion, and the change in the basilar artery diameter induced by the addition of each agent was recorded angiographically. Drug administration markedly reversed the arterial narrowing caused by chronic vasospasm. When the vasodilatory effect of each agent was compared, the dilation induced by nicardipine or papaverine progressively decreased from Day 2 to Day 7, whereas that induced by H-7 increased. Thein vitroexperiment using arterial segments excised from the basilar artery revealed a progressive increase in arterial stiffness from Day 2 to Day 7. Also, there was a significant decrease in the initial half-circumference of the arterial segment, which was at its maximum on Days 4 and 7. However, the alteration in the initial half-circumference was considerably less than that in the angiographic diameter following subarachnoid hemorrhage. These data indicate that the augmented spontaneous tonus of the smooth muscle plays the predominant role in the occurrence of chronic vasospasm. Thus, the involvement of the protein kinase C-mediated contractile system is strongly suggested.
A new model of diffuse brain injury in rats
Authors: Marmarou Anthony , Foda Montasser A. Abd-Elfattah , Brink Wimer van den , Campbell J. , Kita H. , Demetriadou K.
Published: May 2009

✓ This report describes the development of an experimental head injury model capable of producing diffuse brain injury in the rodent. A total of 161 anesthetized adult rats were injured utilizing a simple weight-drop device consisting of a segmented brass weight free-falling through a Plexiglas guide tube. Skull fracture was prevented by cementing a small stainless-steel disc on the calvaria. Two groups of rats were tested: Group 1, consisting of 54 rats, to establish fracture threshold; and Group 2, consisting of 107 animals, to determine the primary cause of death at severe injury levels. Data from Group 1 animals showed that a 450-gm weight falling from a 2-m height (0.9 kg-m) resulted in a mortality rate of 44% with a low incidence (12.5%) of skull fracture. Impact was followed by apnea, convulsions, and moderate hypertension. The surviving rats developed decortication flexion deformity of the forelimbs, with behavioral depression and loss of muscle tone. Data from Group 2 animals suggested that the cause of death was due to central respiratory depression; the mortality rate decreased markedly in animals mechanically ventilated during the impact. Analysis of mathematical models showed that this mass-height combination resulted in a brain acceleration of 900 G and a brain compression gradient of 0.28 mm. It is concluded that this simple model is capable of producing a graded brain injury in the rodent without a massive hypertensive surge or excessive brain-stem damage.
Moyamoya disease with repeated intraventricular hemorrhage due to aneurysm rupture
Authors: Hamada Jun-Ichiro , Hashimoto Nobuo , Tsukahara Tetsuya
Published: May 2009

✓ Two cases of moyamoya disease associated with repeated intraventricular hemorrhage are reported. The origin of bleeding was thought to be a distal aneurysm of the choroidal artery. The aneurysms were confirmed radiologically and histologically. The relationship between moyamoya disease and aneurysms is discussed, and a treatment proposed.
Transcranial Doppler ultrasound findings in cerebral venous sinus thrombosis
Authors: Wardlaw Joanna M. , Vaughan G. T. , Steers A. James W. , Sellar Robin J.
Published: May 2009

✓ Transcranial Doppler ultrasound (TCD) findings are described in a patient with acute thrombosis of the sagittal venous sinus. The TCD finding of prominent venous signals adjacent to the middle cerebral artery gave the first indication of the diagnosis, which was subsequently confirmed by computerized tomography. Awareness of the possible TCD findings in patients with a similar history may lead to a more rapid diagnosis of cerebral venous sinus thrombosis.
Wie erfolgreich war das Dauerwaldkonzept bislang: eine historische Analyse | Continuous cover forests – a success? A historical analysis
Authors: Schmidt Uwe Eduard
Published: May 2009

Since the beginning of the 19th century, differe nt methods of natural regeneration and single-tree orientated systems of management existed in southern Germany and in Switzerland. In the early 1920s, Alfred Möller from Eberswalde created the term “continuous cover forest” (perpetual forest, Dauerwald), which was introduced in the practice of forestry and was controversially discussed by forestry experts. Considerably differing opinions on how to manage this type of forest and on its economical and ecological yield (output) were expressed. During the 1930s, the maxim of perpetual forests temporarily reached the status of a forest economic doctrine in the state forests but it was finally suspended because of additional need of timber in times of war and striving after economic independence. In the aftermath of war, renowned experts of forest science and practice in West and East Germany sought economical concepts of managing the overexploited forests in order to re-establish profit-yielding forests. These efforts led to the founding of the ANW, a forestry panel which turned down the principle of even-aged forests while stressing the importance of sustainability. This can be seen as an equivalent of the traditional principle of continuous cover forests during the 1920s and 1930s. However, after an enthusiastic start, the ANW sank almost into insignificance until the 1980s when the increasing perception of ecology loss re-directed attention towards its ideas. The demands from the ecologically orientated part of our society brought the idea of continuous forests back into current and future discussions in Germany and in other European countries.
Synthesis of the System Modeling and Signal Detecting Circuit of a Novel Vacuum Microelectronic Accelerometer
Authors: Li Dongling , Wen Zhiyu , Wen Zhongquan , He Xuefeng , Yang Yinchuan , Shang Zhengguo
Published: May 2009

A novel high-precision vacuum microelectronic accelerometer has been successfully fabricated and tested in our laboratory. This accelerometer has unique advantages of high sensitivity, fast response, and anti-radiation stability. It is a prototype intended for navigation applications and is required to feature micro-g resolution. This paper briefly describes the structure and working principle of our vacuum microelectronic accelerometer, and the mathematical model is also established. The performances of the accelerometer system are discussed after Matlab modeling. The results show that, the dynamic response of the accelerometer system is significantly improved by choosing appropriate parameters of signal detecting circuit, and the signal detecting circuit is designed. In order to attain good linearity and performance, the closed-loop control mode is adopted. Weak current detection technology is studied, and integral T-style feedback network is used in I/V conversion, which will eliminate high-frequency noise at the front of the circuit. According to the modeling parameters, the low-pass filter is designed. This circuit is simple, reliable, and has high precision. Experiments are done and the results show that the vacuum microelectronic accelerometer exhibits good linearity over -1 g to +1 g, an output sensitivity of 543 mV/g, and a nonlinearity of 0.94 %.
Symptoms of Depression Predict the Trajectory of Pain Among Patients with Early Inflammatory Arthritis: A Path Analysis Approach to Assessing Change
Authors: SCHIEIR ORIT , THOMBS BRETT D. , HUDSON MARIE , TAILLEFER SUZANNE , STEELE RUSSELL , BERKSON LAEORA , BERTRAND CAROLE , COUTURE FRANCOIS , FITZCHARLES MARY-ANN , GAGNÉ MICHEL , GARFIELD BRUCE , GUTKOWSKI ANDRZEJ , KANG HARB , KAPUSTA MORTON , LIGIER SOPHIE , MATHIEU JEAN-PIERRE , MÉNARD HENRI , MERCILLE SUZANNE , STARR MICHAEL , STEIN MICHAEL , ZUMMER MICHEL , BARON MURRAY
Published: May 2009

Objective.

To assess the longitudinal relationships, including directionality, among chronic pain, symptoms of depression, and disease activity in patients with early inflammatory arthritis (EIA).

Methods.

One hundred eighty patients with EIA completed an examination, including swollen joint count, and were administered the Center for Epidemiological Studies Depression Scale (CES-D) and the McGill Pain Questionnaire (MPQ) at 2 timepoints 6 months apart. Cross-lagged panel path analysis was used to simultaneously assess concurrent and longitudinal relationships among pain, symptoms of depression, and number of swollen joints.

Results.

Pain, symptoms of depression, and number of swollen joints decreased over time (p < 0.001) and were prospectively linked to pain, symptoms of depression, and number of swollen joints, respectively, at 6 months. Symptoms of depression and pain were correlated with each other at baseline (0.47) and at 6-month followup assessments (0.28). Baseline symptoms of depression significantly predicted pain symptoms at 6 months (standardized regression coefficient = 0.28, p = 0.001), whereas pain and disease activity did not predict the course of any other variable after controlling for baseline values.

Conclusion.

Symptoms of depression predicted the trajectory of pain from baseline to 6 months. In addition, there were reciprocal/bidirectional associations between pain and symptoms of depression over time. More research is needed to better understand the relationship between pain and depressive symptoms and how to best manage patients with EIA who have high levels of both.
Dendritic Cells Contribute to Autoimmune Kidney Injury in MRL-Faslpr Mice
Authors: IWATA YASUNORI , FURUICHI KENGO , SAKAI NORIHIKO , YAMAUCHI HIROYUKI , SHINOZAKI YASUYUKI , ZHOU HAIYAN , KUROKAWA YUKIE , TOYAMA TADASHI , KITAJIMA SHINJI , OKUMURA TOSHIYA , YAMADA SHINGO , MARUYAMA IKURO , MATSUSHIMA KOUJI , KANEKO SHUICHI , WADA TAKASHI
Published: May 2009

Objective.

Dendritic cells (DC) contribute to autoimmune disease progression and pathogenesis. Mature DC have been reported to secrete high mobility group box protein (HMGB-1), a novel inflammatory cytokine, via p38 mitogen-activated protein kinase (MAPK) activation. We investigated whether DC are involved in progression of autoimmune diseases followed by secretion of HMGB-1 via p38 MAPK activation in a lupus-prone mouse model.

Methods.

FR167653, a specific inhibitor of p38 MAPK, was given orally from 3 months of age in MRL-Faslpr mice. Cultured DC, treated with or without FR167653, were stimulated with tumor necrosis factor-α.

Results.

Inhibition of p38 MAPK led to a reduction in the number of CD11c-positive cells, including those with the mature phenotype, in the diseased kidney and spleen, which resulted in improvement of kidney pathology in MRL-Faslpr mice. The number of CD11c-positive cells in circulation was also reduced. HMGB-1 protein and transcripts detected in the diseased kidney, and the number of cells dual-positive for HMGB-1 and CD11c, were reduced by inhibition of p38 MAPK. Maturation of cultured DC and increased cytokines, including HMGB-1, in the supernatant were inhibited by FR167653 treatment. These results suggest that DC are involved in the progression of autoimmune kidney diseases in MRL-Faslpr mice followed by HMGB-1 secretion via p38 MAPK activation.

Conclusion.

Our results indicated that DC secrete HMGB-1 via p38 MAPK activation to participate in autoimmunity in MRL-Faslpr mice.
Cementoplasty in the Treatment of Avascular Necrosis of the Hip
Authors: REUTER NICOLAS , ROMIER ALBAN , HAMBOURG ZEPHIR , PALMIERI FRÉDÉRIC , FAYET DOMINIQUE , PALLOT-PRADES BÉATRICE , COLLET PHILIPPE , FESSY MICHEL-HENRY , FARIZON FRÉDÉRIC , BARRAL FABRICE G. , THOMAS THIERRY
Published: May 2009

Objective.

This retrospective study evaluated the role of percutaneous cementoplasty in the treatment of avascular necrosis (AVN) of the hip in order to postpone or avoid total hip replacement.

Methods.

The study population comprised 40 patients (47 hips) with mean age of 46 ± 4.7 years and mean body mass index of 26.7 ± 4.6 kg/m2. AVN was classified according to the Ficat-Arlet classification as one stage I, 30 stage II, and 16 stage III. The minimum followup was 9 months.

Results.

It was found that 74.5% of hips were secondarily operated for total hip replacement a mean of 19.9 ± 15 months (median 14 mo) after cementoplasty. As well, 94% of patients with stage 3AVN and 68% with stage 2AVN underwent surgery. Twelve hips were not operated, with a mean followup of 39 ± 19.2 months. Pain decreased by more than 80% after cementoplasty in two-thirds of patients, but the mean pain-free interval was only 8.1 ± 6.6 months (median 5 mo). Nineteen of the 29 working patients were able to transiently return to work. The outcome was more unfavorable with radiological stage III AVN, joint effusion, and/or a double-line sign around the lesions on magnetic resonance images.

Conclusion.

Despite early relief of pain, the results of the cementoplasty technique were disappointing, with need for arthroplasty surgery in most cases within 2 years. Alternative percutaneous techniques using different filler materials with osteoinductive properties should be evaluated in further studies.
Limitations to the 6-Minute Walk Test in Interstitial Lung Disease and Pulmonary Hypertension in Scleroderma
Authors: GARIN MARGARET C. , HIGHLAND KRISTIN B. , SILVER RICHARD M. , STRANGE CHARLIE
Published: May 2009

Objective.

To determine factors that influence 6-minute walk distance (6MWD) in patients with scleroderma (systemic sclerosis, SSc)-interstitial lung disease (ILD), SSc-pulmonary hypertension (PH), and idiopathic pulmonary fibrosis (IPF).

Methods.

We retrospectively evaluated all patients with SSc or IPF who performed a 6-minute walk test (6MWT) at a university hospital between 1999 and 2003. Chi-square, ANOVA, simple linear regression, and backwards elimination multivariable regressions were performed.

Results.

Forty-eight consecutive IPF patients with 6MWT were compared to 33 patients with SSc-ILD, 13 with SSc-PH, 19 with both SSc-ILD and SSc-PH (SSc-Both), and 15 with SSc without ILD or PH (SSc-Neither). Mean 6MWD did not differ between groups. Limitations to 6MWT trended toward dyspnea in IPF and lower extremity pain in SSc. SSc-Both had dyspnea limitation more than other SSc subgroups (p = 0.017). Percentage predicted forced vital capacity (FVC%) and percentage predicted carbon monoxide diffusing capacity (DLCO%) were more strongly predictive of 6MWD in IPF than in SSc; however, exclusion of SSc subjects with pain limitation improved the predictive value. Significant correlates of 6MWD in multivariable analysis differed between subgroups.

Conclusion.

Pain limitations confound the utility of the 6MWT, particularly in SSc. Pain may cause failure to reach a dyspnea limitation during 6MWT, especially in SSc patients without both ILD and PH. Correlates of 6MWD differ between SSc subgroups and IPF; therefore, the 6MWT distance is not always reflective of the same physiological process. 6MWT interpretation should include consideration of vascular, pulmonary, and musculoskeletal exercise limitations.