bluuebunny/crossref_metadata_2025 huggingface dataset:
Invading meningiomas of the sphenoid ridge
Authors: Bonnal Joël , Thibaut André , Brotchi Jacques , Born Jacques
Published: May 2009

✓ The authors report a series of 34 meningiomas of the sphenoid ridge. Eight tumors were totally removed uneventfully: two from the middle sphenoid ridge and six from the pterion or Sylvian point. Five tumors were not operated on because of their extensions or the patient's age. Twenty-one tumors raised serious surgical problems, resulting in a classification into three groups: deep or clinoidal, invading beyond the sphenoid wings, and a combination of both. Histological study of the hyperostotic bone showed meningiomatous cells in the bone in 12 of 13 cases so examined.

Surgical limitations included invasion of the cavernous sinus (15 cases), of the dura mater of the sella turcica (seven cases), of the lateral part of the sphenoid body at the insertion point of the ala magna (seven cases), and of the common tendinous annulus of Zinn in the orbit (five cases), and basilar extracranial extension, particularly in the pterygomaxillary fossa (three cases). Following extensive removal, there were no early recurrences and three late recurrences (9 years and more). In 13 cases with a follow-up period of 1 to 8 years, there were no clinical recurrences. In only two cases was the meningioma totally removed. There were three postoperative deaths, two cases of hemiparesis with aphasia and epilepsy, one case with a frontal lobe syndrome, and nine with slight oculomotor, visual, or esthetic sequelae.
Acquired hemophilia, meningioma, and diphenylhydantoin therapy
Authors: O'Reilly Robert A. , Hamilton Richard D.
Published: May 2009

✓ A patient is reported in whom a meningioma of the lateral one-third of the sphenoid ridge was completely removed and long-term prophylaxis for seizures with diphenylhydantoin was prescribed. One and a half years later, a powerful inhibitor developed that specifically neutralized Factor VIII, the antihemophilic factor, and caused an acquired state of hemophilia. The 4-month hemorrhagic disorder was characterized initially by painless hematuria and later by intracerebral and extradural hematomas at the operative site of the previously excised meningioma. Despite the transfusion of massive quantities of concentrates of clotting factors, and the surgical evacuation of the recurrent hematomas on two occasions, the localized bleeding could not be staunched and the patient died. The types of inhibitors that cause acquired hemophilia and their modes of treatment are examined. Although it is possible that the Factor VIII inhibitor in this patient was induced by the meningioma, most previously reported tumors associated with acquired hemophilia have had an immunological basis. The most probable explanation for the acquired hemophilia in this patient was an inhibitor to Factor VIII from an autoantibody induced by the long-term use of diphenylhydantoin.
Percutaneous tunnel ventriculostomy
Authors: Friedman William A. , Vries John K.
Published: May 2009

✓ External ventricular drainage is an important therapeutic adjunct in neurosurgical practice. Unfortunately, this procedure has been associated with a significant incidence of ventriculitis. A major source for many of these infections has been bacterial contamination of the tract of the ventricular catheter, at the site where it enters the scalp. To prevent this problem, the authors have devised a new ventriculostomy technique that involves tunneling the ventricular catheter through the scalp, between the dermis and the galea. One hundred consecutive procedures in 66 patients are analyzed in this paper. The average duration of drainage was 6.2 days. There were no infections subsequent to the insertion of the ventricular catheter in this group of patients.
Influence of respiratory stress and hypertension upon the blood-brain barrier
Authors: Robinson Joe Sam , Moody Robert A.
Published: May 2009

✓ The effects of acute hypertension and respiratory stress induced by Aramine (metaraminol bitartrate) upon blood-brain barrier (BBB) permeability to horseradish peroxidase (HRP) were studied in adult inbred white rats. The BBB permeability was quantitated by slicing the brain of each animal into 500-µ thick sections, incubating the sections using the Reese-Karnovsky method, and counting all observed HRP perivascular exudates. No evidence of BBB compromise or significant elevation of blood pressure (BP) was observed in the following experimental groups: 1) control group of five animals; 2) hyperventilated group of five animals (final mean arterial blood gases: pO2, 104.2 mm Hg; pCO2, 24.8 mm Hg; pH, 7.53); 3) anoxicstress group of five animals (final mean arterial blood gases: pCO2, 31.4 mm Hg; pCO2, 58.2 mm Hg; pH, 7.21). However, in a group of 15 animals subjected to anoxic stress followed by hyperventilation, in addition to extreme changes in the levels of arterial blood gases, a significant BP increase occurred (mean BP increase per second, 3.43 ± 0.25 mm Hg; final mean BP, 163.3 ± 3.18 mm Hg); as well as significant BBB opening (mean number of HRP exudates per animal, 12.2 ± 0.85). Likewise, a final group of 10 animals given intravenous Aramine displayed a significant systemic BP elevation (mean BP increase per second, 6.9 ± 0.38 mm Hg; final mean BP, 165.8 ± 3.16 mm Hg), accompanied by BBB opening (mean number of exudates per animal, 51.5 ± 5.95). The variable most strongly associated with the degree of barrier opening was the rate of BP rise (correlation coefficient = + 0.84).
Abnormal impulse generation in focally demyelinated trigeminal roots
Authors: Burchiel Kim J.
Published: May 2009

✓ In 12 cats and two Macaca mulatta monkeys, areas of chronic focal injury were induced in the trigeminal root by implantation of a chromic suture in the nerve near its entry into the brain stem. Experimental lesions were examined histologically and electrophysiologically at 1 week, 3 weeks, and 6 weeks after surgery. At 3 weeks following implantation, lesioned nerves showed areas of focal inflammation surrounding implanted sutures with prominent demyelination of adjacent axons. A total of 497 trigeminal units were studied, 304 of which had associated demyelination of the root. In these 304 cells, two types of abnormal impulse generation from areas of focal demyelination were recorded. Reflected orthodromic action potentials and prolonged high-frequency after-discharges following short priming trains of orthodromic stimuli were observed in 23% and 4% of cells, respectively. Ectopic spike initiation from areas of focal demyelination was not dependent upon anatomical continuity of the nerve with the brain stem, was augmented by hyperventilation, and could be eliminated by the intravenous administration of diphenylhydantoin sodium. The relevance of these findings to the pathophysiological mechanisms of pain syndromes involving peripheral nerves in general and the trigeminal system in particular is discussed.
Effects of cholinomimetic drugs on sudomotor, metabolic, respiratory, vasomotor, and temperature response in palmar hyperhidrosis
Authors: Shih Chun-Jen , Lin Mao-Tsun
Published: May 2009

✓ The effects of cholinomimetic drugs such as mecholyl (methacholine) and pilocarpine on autonomic functions (including sudomotor, metabolic, respiratory, vasomotor, and temperature responses) were assessed at room temperature (24°C) in three groups of individuals, including normal, hyperhidrotic, and denervated subjects. The normal group had no palmar hyerhidrosis, with intact T2–3 ganglia, the hyperhidrotic group had palmar hyperhidrosis with intact T2–3 ganglia, and the denervated group had palmar hyperhidrosis treated with T2–3 ganglionectomy. Subcutaneous administration of mecholyl and pilocarpine each produced a fall in oral temperature in the normal group. The hypothermia was brought about by a decrease in metabolic rate, an increase in local sweating rate (mainly of the upper limb and trunk), and an increase in cutaneous circulation (estimated by an increase in the upper limb and trunk skin temperatures). The autonomic functions induced by these cholinomimetic drugs were antagonized by pretreatment with atropine sulfate (an antagonist of cholinergic receptors). Moreover, the hypothermia induced by mecholyl or pilocarpine was greatly reduced in the hyperhidrotic group. The reduction in the cholinomimetic-induced hypothermia in the hyperhidrotic group was due to the reduced sudomotor and metabolic responses after the injections of these cholinomimetic drugs, as compared to those of the normal group. However, neither the excessive sweating of the palms nor the reduced cholinergic responses in the hyperhidrotic group was observed after T2–3 ganglionectomy. The data indicate that the T2–3 ganglia play a role in the elaboration or modulation of the sudomotor and metabolic responses induced by activation of certain cholinergic receptors in humans.
The “bonnet bypass”
Authors: Spetzler Robert F. , Roski Richard A. , Rhodes Robert S. , Modic Michael T.
Published: May 2009

✓ A saphenous vein bypass graft from the contralateral superficial temporal artery to the ipsilateral middle cerebral artery was performed in a patient who required occlusion of his left common carotid artery. This procedure was used because of the unavailability of an ipsilateral donor artery. The bypass is working well 8 months postoperatively.
Intrasellar granuloma
Authors: Pozo José Manuel Del , Roda J. Enrique , Montoya Jesús G. , Iglesias José R. , Hurtado Alejandro
Published: May 2009

✓ A case of giant-cell granuloma of the pituitary in a 28-year-old woman is reported. Clinical complaints included headache and amenorrhea. Endocrinological studies showed hypopituitarism. X-ray films showed enlargement of the sella turcica.
Nonsurgical resolution of a brain-stem abscess
Authors: Vaquero Jesús , Cabezudo José M. , Leunda Guillermo
Published: May 2009

✓ A case of solitary mesencephalic abscess in a 13-year-old boy is presented. The computerized tomography and clinical pictures, indicating a Weber syndrome and obstructive hydrocephalus, resolved totally 20 days after implantation of a ventriculoatrial shunt and treatment with intravenous chloramphenicol and penicillin. This is the fifth reported case of survival in a patient with a brain-stem abscess, and the first in which this outcome has been achieved without surgical drainage of the abscess.
The value of decompression for acute experimental spinal cord compression injury
Authors: Dolan Eugen J. , Tator Charles H. , Endrenyi Laszlo
Published: May 2009

✓ A clip compression method was used to produce acute spinal cord compression injury in rats. The force and duration of the spinal cord compression were independently varied, and functional recovery of the cord was assessed using the inclined plane technique. Mathematical modeling produced a curve defining the relationship between force, duration, and functional recovery for each week after injury. The study clearly showed the beneficial effect of decompression and that increasing either the force or duration of compression, or both, caused a reduction in recovery.
Impaction fracture of the lumbar vertebrae with dural tear
Authors: Miller Carole A. , Dewey Richard C. , Hunt William E.
Published: May 2009

✓ The authors describe a lumbar spine fracture that is characterized on anteroposterior x-ray views by separation of the pedicular shadows. It is almost invariably associated with posterior interlaminar herniation of the cauda equina through a dorsal dural split, and anterolateral entrapment or amputation of the nerve root. The fracture is unstable and requires internal fixation and fusion at the time of neurolysis. Fractures meeting these criteria should be explored as soon as the patient's condition permits. Myelography is usually unnecessary and may be contraindicated in some cases. The postulated mechanism of injury is hyperextension with vertical impaction and rupture of the ring made up of the lamina, pedicle, and vertebral body. The ring is fractured in several places in a manner similar to that seen in “Jefferson fracture” of C-1. The special anatomical relationships of the thoracolumbar junction and the plane of the lumbar facets are also discussed.
Evolution of craniotomy as a debridement technique for penetrating craniocerebral injuries
Authors: Rish Berkley L. , Dillon J. Daniel , Caveness William F. , Mohr Jay P. , Kistler J. Phillip , Weiss George H.
Published: May 2009

✓ A craniotomy debridement technique was recommended for penetrating craniocerebral injuries as early as 1940, in World War II. However, with due consideration for the bacterial contamination of penetrating injuries, the safety of this technique was questionable. The technique has been recommended in each succeeding war, but no data substantiating the safety or eventual sequelae have been available. Analysis of the data from the large Head Injury Registry of Vietnam casualties indicates that, in properly selected cases, debridement by craniotomy technique can be safe and efficacious.
Treatment of posttraumatic carotid-cavernous fistula using a detachable balloon catheter
Authors: Benati Aldo , Maschio Adriano , Perini Stefano , Beltramello Alberto
Published: May 2009

✓ Five cases of posttraumatic carotid-cavernous fistula are reported. The fistulas were occluded by intravascular detachable balloons, as described by Serbinenko and later modified by Debrun. The good results obtained in three of these patients illustrate the value of this procedure, as it allows a direct obliteration of the fistula with preservation of the internal carotid blood flow.
Cerebral cavernous angiomas in children
Authors: Pozzati Eugenio , Padovani Roberto , Morrone Bernardino , Finizio Francesco , Gaist Giulio
Published: May 2009

✓ Five cases of cerebral cavernous angiomas in children are presented. Three children had seizures as the sole manifestation of the lesion, and two had intracerebral bleeding. These malformations are encountered more commonly in adults in the third to fifth decade, and are found most frequently in the white matter of the cerebral hemispheres. Intracranial bleeding, seizures, headaches, and slowly developing focal signs are the usual presenting complaints. In childhood, seizures are the initial symptom of the malformation in many cases. The value of computerized tomography (CT) in the detection of such malformations is stressed, and CT findings that are characteristic of cavernous angiomas are described.
Cavernous angiomas of the pineal region
Authors: Vaquero Jesús , Carrillo Rafael , Cabezudo José , Leunda Guillermo , Villoria Francisco , Bravo Gonzalo
Published: May 2009

✓ Two cases of cavernous angiomas of the pineal region are presented. The possibility that a mass in the pineal region could be a cavernous angioma should be considered when deciding upon early surgery or a trial of radiotherapy.
Intracranial esthesioneuroblastoma associated with unilateral visual loss
Authors: Goldhammer Yochanan , Sadeh Menachem , Tadmor Rina , Leventon George
Published: May 2009

✓ Esthesioneuroblastoma is a rare tumor that arises from the olfactory mucosa and presents usually as a mass in the nasal cavity. Neurological complications occur in about 20% of these cases. Nine cases have been recorded so far in which the neoplasm manifested initially as an intracranial mass. These cases are reviewed and another patient, presenting with progressive unilateral visual loss, is reported.
Pituitary abscess
Authors: Selosse Paul , Mahler Charles , Klaes Robert L.
Published: May 2009

✓ A case of pituitary abscess is reported in which the diagnosis was made during surgery. The difficulties in diagnosis and management of patients with this rare entity are stressed.
Ventriculovesical shunt
Authors: West Charles G. H.
Published: May 2009

✓ A patient is reported whose hydrocephalus was controlled by diverting the ventricular cerebrospinal fluid directly into the urinary bladder. This drainage route may have a useful place in the management of the adult pressure-sensitive patient whose more conventional shunt requires frequent revision for repeated obstruction.
One-stage posterior decompression and reconstruction of the cervical spine by using pedicle screw fixation systems
Authors: Abumi Kuniyoshi , Kaneda Kiyoshi , Shono Yasuhiro , Fujiya Masanori
Published: May 2009

Object. This retrospective study was conducted to analyze the results of one-stage posterior decompression and reconstruction of the cervical spine by using pedicle screw fixation systems in 46 patients.

Methods. Causes of cervical myelopathy in these 46 patients included spondylosis or ossification of the posterior longitudinal ligament, rheumatoid arthritis, metastatic or primary vertebral tumors, cervical spinal injuries, and spinal cord tumor. Thirty-three patients underwent this one-stage procedure as primary surgery. In the remaining 13 patients who had previously undergone laminectomies, the one-stage procedure was performed as salvage surgery. Cervical pedicle screws were inserted into the pedicles after probing and tapping. Graft bone was placed on the bilateral lateral masses, and pedicle screws were interconnected longitudinally by either plates or rods. Postoperatively, 26 patients showed improved neurological status (at least one grade improvement on Frankel's functional classification). There were no cases of neurological deterioration postoperatively. Solid bony fusion was obtained in all patients, except in seven patients with metastatic tumor who did not receive bone grafts. Correction of kyphosis was satisfactory. Postoperative radiological evaluation revealed that 10 (5.3%) of 190 screws inserted into the cervical vertebrae had perforated the cortex of the pedicles; however, no neurovascular complications were caused by the perforations.

Conclusions. The pedicle screw fixation procedure, which does not require the lamina to be used as a stabilizing anchor, has proven to be valuable when performing one-stage posterior decompressive and reconstructive surgery in the cervical spine. The risk to neurovascular structures in this procedure, however, cannot be completely eliminated. Thorough knowledge of local anatomy and application of established surgical techniques are essential for this procedure.
Lateral exit-zone stenosis and lumbar radiculopathy
Authors: Maher Cormac O. , Henderson Fraser C.
Published: May 2009

Object. Hypertrophy of the superior facet of the inferior vertebra, resulting in a compression of the nerve root at the lateral foraminal exit, is a recognized cause of radicular symptoms, particularly in patients in whom previous lumbar spine surgery has failed. The lesion-specific presenting symptoms, imaging findings, and surgical treatment of this lesion, however, have received little attention. The authors prospectively studied a series of eight consecutive patients, in whom a diagnosis of lumbar stenosis at the lateral foraminal exit had been made, to elucidate the common presenting signs and symptoms of this disorder, as well as to evaluate the success of the operative treatment.

Methods. The eight patients were selected from a group of 250 consecutive patients who presented to a tertiary-care hospital and in whom a diagnosis of long-standing lumbar radiculopathy had been made. In all cases the diagnosis was confirmed by imaging studies and by intraoperative findings. The authors performed decompressive procedures on the nerve root via a medial facet-sparing approach.

Conclusions. The authors conclude that this lesion presents with characteristic physical findings and on imaging studies that distinguish it from other causes of radiculopathy, and they propose a lesion-specific, facet-sparing surgical technique that has yielded excellent results.
The role of bupivacaine in early postoperative pain control after lumbar decompression
Authors: Chadduck James B. , Sneyd J. Robert , Pobereskin Louis H.
Published: May 2009

Object. The authors studied the effect of immediate postoperative administration of bupivacaine in patients who underwent a lumbar decompressive procedure.

Methods. In this randomized double-blind trial, 50 patients who underwent elective lumbar decompression after induction of general anesthetic received a postoperative bilateral paravertebral 40-ml intramuscular application of either saline (0.9%) or bupivacaine (0.25%). For delivering morphine, both groups used a patient-controlled analgesia system for 24 hours postsurgery. Pain scores, 10-cm visual analog scale scores, and morphine consumption were similar between groups with no significant differences (p > 0.05).

Conclusions. Results of subgroup analysis suggested strongly that perioperative administration of methylprednisolone in a sustained-release preparation was associated with a reduction in postoperative pain (p < 0.05).
A biomechanical evaluation of occipitocervical instrumentation: screw compared with wire fixation
Authors: Hurlbert R. John , Crawford Neil R. , Choi Won Gyu , Dickman Curtis A.
Published: May 2009

Object. The purpose of this study was to compare cable techniques used in occipitocervical fixation with two types of screw fixation. The authors hypothesized that screw fixation would provide superior immobilization compared with cable methods.

Methods. Ten cadaveric specimens were prepared for biomechanical analyses by using standard techniques. Angular and linear displacement data were recorded from the occiput to C-6 with infrared optical sensors after conditioning runs. Specimens underwent retesting after fatiguing. Six methods of fixation were analyzed: Steinmann pin with and without C-1 incorporation; Cotrel-Dubousett horseshoe with and without C-1 incorporation; Mayfield loop with C1–2 transarticular screw fixation; and a custom-designed occipitocervical transarticular screw-plate system. Sublaminar techniques were extended to include C-3 in the fusion construct, whereas transarticular techniques incorporated the occiput, C-1, and C-2 only.

All methods of fixation provided significant immobilization in all specimens compared with the nonconstrained destabilized state. Despite incorporation of an additional vertebral segment, sublaminar techniques performed worse as a function of applied load than screw fixation techniques. Following fatiguing, these differences were more pronounced. The sublaminar techniques failed most prominently in flexion—extension and in axial rotation. On gross inspection, increased angular displacement associated with loosening of the sublaminar cables was observed.

Conclusion. Occipitocervical fixation can be performed using a variety of techniques; all bestow significant immobilization compared with the destabilized spine. All methods tested in this study were susceptible to fatigue and loss of reduction and were weakest in resisting vertical settling. Screw fixation of the occiput—C2 reduces the number of vertebral segments that are necessary to incorporate into the fusion construct while providing superior immobilization and resistance to fatigue and vertical settling compared with sublaminar methods.
Stability of the craniovertebral junction after unilateral occipital condyle resection: a biomechanical study
Authors: Vishteh A. Giancarlo , Crawford Neil R. , Melton M. Stephen , Spetzler Robert F. , Sonntag Volker K. H. , Dickman Curtis A.
Published: May 2009

Object. The authors sought to determine the biomechanics of the occipitoatlantal (occiput [Oc]—C1) and atlantoaxial (C1–2) motion segments after unilateral gradient condylectomy.

Methods. Six human cadaveric specimens (skull with attached upper cervical spine) underwent nondestructive biomechanical testing (physiological loads) during flexion—extension, lateral bending, and axial rotation. Axial translation from tension to compression was also studied across Oc—C2. Each specimen served as its own control and underwent baseline testing in the intact state. The specimens were then tested after progressive unilateral condylectomy (25% resection until completion), which was performed using frameless stereotactic guidance. At Oc—C1 for all motions that were tested, mobility increased significantly compared to baseline after a 50% condylectomy. Flexion—extension, lateral bending, and axial rotation increased 15.3%, 40.8%, and 28.1%, respectively. At C1–2, hypermobility during flexion—extension occurred after a 25% condylectomy, during axial rotation after 75% condylectomy, and during lateral bending after a 100% condylectomy.

Conclusions. Resection of 50% or more of the occipital condyle produces statistically significant hypermobility at Oc—C1. After a 75% resection, the biomechanics of the Oc—C1 and C1–2 motion segments change considerably. Performing fusion of the craniovertebral junction should therefore be considered if half or more of one occipital condyle is resected.
Convective delivery of macromolecules into the naive and traumatized spinal cords of rats
Authors: Wood J. David , Lonser Russell R. , Gogate Nitin , Morrison Paul F. , Oldfield Edward H.
Published: May 2009

Object. Many macromolecules have the potential to enhance recovery after injury and other lesions of the spinal cord, but because of the limited penetration of these compounds across the blood—spinal cord barrier, they cannot be used effectively. To determine if convective delivery could be used in a common animal model to investigate potential therapeutic macromolecules and to examine the effects of trauma on convective delivery in that model, the authors examined the distribution of a macromolecule in naive and traumatized rat spinal cords.

Methods. Using convection, various infusion volumes ([Vi]; 1, 2, and 4 µl) of 14C-albumin were infused into the dorsal columns of 13 naive and five traumatized rat spinal cords. Volume of distribution (Vd), homogeneity, percentage of recovery, and anatomical location were determined using quantitative autoradiography, scintillation analysis, calculation of kurtosis (K) value, and histological analysis. In the nontraumatized group, Vd was linearly proportional (R2 = 0.98) to Vi (Vd/Vi, 4.3 ± 0.6; mean ± standard deviation), with increases in Vd resulting from linear expansion (R2 = 0.94) primarily in the craniocaudal dimension. In the traumatized spinal cords, the Vd/Vi ratio (3.7 ± 0.5) was smaller (p < 0.02) and distributions were less confined to the craniocaudal dimension, with significantly larger cross-sectional distributions in the region of injury (p < 0.02) compared to the noninjured spinal cords. Histological analysis revealed that after infusion into the dorsal columns, albumin distribution in naive cords was limited to the dorsal white matter, but in the traumatized cords there was penetration into the central gray matter. The distribution of the infusate was homogeneous in the nontraumatized (K = −1.1) and traumatized (K = −1.1) spinal cords. Recovery of radioactivity was not significantly different (p > 0.05) between the nontraumatized (84.8 ± 6.8%) and traumatized (79.7 ± 12.1%) groups.

Conclusions. Direct convective delivery of infusate can be used to distribute macromolecules in a predictable, homogeneous manner over significant volumes of naive and traumatized rat spinal cord. These characteristics make it a valuable tool to investigate the therapeutic potential of various compounds for the treatment of injury and spinal cord disease.
Complex cervical spine neoplastic disease: reconstruction after surgery by using a vascularized fibular strut graft
Authors: Wright Neill M. , Kaufman Bruce A. , Haughey Bruce H. , Lauryssen Carl
Published: May 2009

✓ The authors report a case of an aggressive chordoma in the cervical spine of a 15-year-old girl who underwent radical resection followed by reconstruction using an anterior vascularized fibular strut graft and posterior arthrodesis prior to receiving immediate postoperative radiation therapy. The patient had successful graft incorporation 4 months postoperatively. The authors review the advantages of using vascularized fibular strut grafts for the treatment of multilevel cervical spine neoplastic disease and discuss the theoretical advantages of using vascularized grafts that tolerate therapeutic levels of radiation.
Spontaneous regression of a herniated cervical disc in a patient with myelopathy
Authors: Song Jun-Hyeok , Park Hyang-Kwon , Shin Kyu-Man
Published: May 2009

✓ The authors present a case of spontaneous regression of a herniated cervical nucleus pulposus in a patient with myelopathy. This 37-year-old woman developed sudden quadriparesis; she had reported no history of trauma. Magnetic resonance (MR) imaging revealed a large disc herniation and increased signal intensity of the cord at the C5–6 level. The extruded disc fragment was found to have resolved on follow-up MR imaging after 28 months, despite the fact that the patient had undergone no specific treatment. The patient's symptoms had subsided almost totally. This is the first case of MR-documented regression of a cervical disc herniation in a patient with myelopathy.
Subaxial cervical synovial cyst presenting with myelopathy
Authors: Cudlip Simon , Johnston Francis , Marsh Henry
Published: May 2009

✓ Synovial cysts occur infrequently in the spinal canal and are most often associated with degenerative facet joints. Despite the prevalence of degenerative spinal disease, symptomatic synovial cysts are extremely uncommon. There have been only two previously reported cases of subaxial degenerative synovial cysts of the cervical spine in patients who presented with a clinical picture of spinal cord compression. The authors report three additional patients treated for degenerative cervical synovial cysts who presented with myelopathy. In all three patients the cyst was successfully excised and a good clinical outcome achieved.
Transarterial embolization of aneurysms associated with spinal cord arteriovenous malformations
Authors: Konan Alexis Victorien , Raymond Jean , Roy Daniel
Published: May 2009

✓ The authors sought to show the feasibility and discuss the rationale of embolization of aneurysms associated with spinal cord arteriovenous malformations (SCAVMs). The authors reviewed the clinical presentation, magnetic resonance (MR) images, spinal angiograms, and clinical evolution of four patients treated for aneurysms associated with an SCAVM. Aneurysms were located on branches of the anterior spinal artery in three patients and on radiculopial arteries in two patients; one patient harbored two lesions. Treatment consisted of superselective bucrylate embolization of the branches harboring the aneurysms, with preservation of the arterial axis. Follow-up angiograms were obtained at 3 to 6 months postembolization in all patients.

All patients presented with hemorrhagic events. Hematomyelia was clearly related to a sulcocommissural or a vasa corona aneurysm in two patients. Another sulcocommissural aneurysm and multiple radiculopial aneurysms were presumed to be the cause of subarachnoid hemorrhage in two other patients. One patient harbored aneurysms on a sulcocommissural artery and on a radiculopial artery. All aneurysms were permanently obliterated. In one patient with a single fistula, the SCAVM was cured. The SCAVM was only partially obliterated (95, 50, and 20% in apparent volume) in three other patients. There were no complications or rebleeding episodes during a follow-up period of 17 to 37 months.

Aneurysms associated with SCAVMs can be eradicated by supraselective embolization, even on the anterior spinal artery territory. For patients presenting with hemorrhage and prohibitive risk of complete resection, embolization of aneurysms may decrease the risk of further rebleeding.
Risk factors for adjacent-segment failure following lumbar fixation with rigid instrumentation for degenerative instability
Authors: Etebar Shahin , Cahill David W.
Published: May 2009

Object. The authors performed a retrospective analysis of 125 consecutive patients in whom instrumentation was placed to promote lumbar fusion for the treatment of degenerative instability. All procedures were performed by a single surgeon. The authors sought to determine the risk factors for next-segment degeneration after lumbar spinal fusion with rigid instrumentation.

Methods. Thirty-one of 125 fusion procedures were performed in women who were postmenopausal. A total of 18 of 125 patients developed symptomatic next-segment degeneration at a previously asymptomatic level; 15 were postmenopausal women. Data were obtained in patients with next-segment failure based on radiographic studies, neurological assessment, demographic factors, and sequential follow-up examinations. The mean follow-up period for this group was 44.8 months. All women were postmenopausal, and 53% received biphosphonate drugs and calcium supplementation preoperatively for osteopenia. Twenty percent of all patients with next-segment failure were cigarette smokers. Next-segment diseases included spondylolisthesis (39%), spinal canal stenosis due to disc herniation and/or facet hypertrophy (33%), stress fracture of the adjacent vertebral body (28%), and scoliosis (17%). Patients frequently had more than one degenerative process at the next segment.

Conclusions. The risk of adjacent-segment failure is clearly higher for patients in whom lumbar fusion with rigid instrumentation is performed to treat degenerative instability. This risk appears to be especially high in postmenopausal women.
Cervical laminectomy without fusion in patients with rheumatoid arthritis
Authors: Christensson Dan , Säveland Hans , Zygmunt Stefan , Jonsson Kjell , Rydholm Urban
Published: May 2009

Object. The authors performed a prospective study to determine whether cervical laminectomy without simultaneous fusion results in spinal instability.

Methods. Because of clinical and radiographic signs of cord compression, 15 patients with rheumatoid arthritis (including one with Bechterew's disease) and severe involvement of the cervical spine underwent decompressive laminectomy without fusion performed on one or more levels. Preoperative flexion—extension radiographs demonstrated dislocation but no signs of instability at the level of cord compression.

Clinical and radiological reexamination were performed twice at a median of 15 months (6–24 months) and 43 months (28–72 months) postoperatively. One patient developed severe vertical translocation 28 months after undergoing a C-1 laminectomy, which led to sudden tetraplegia. She required reoperation in which posterior fusion was performed. No signs of additional instability at the operated levels were found in the remaining 14 patients. In three patients increased but stable dislocation was demonstrated. The results of clinical examination were favorable in most patients, with improvement of neurological symptoms and less pain.

Conclusions. The authors conclude that decompressive laminectomy in which the facet joints are preserved can be performed in the rheumatoid arthritis-affected cervical spine in selected patients in whom signs of cord compression are demonstrated, but in whom radiographic and preoperative signs of instability are not. Performing a simultaneous fusion procedure does not always appear necessary. Vertical translocation must be detected early, and if present, a C-1 laminectomy should be followed by occipitocervical fusion.
A prospective randomized double-blind controlled trial to evaluate the efficacy of an analgesic epidural paste following lumbar decompressive surgery
Authors: Hurlbert R. John , Theodore Nicholas , Drabier Janine B. , Magwood Andrea M. , Sonntag Volker K. H.
Published: May 2009

Object. Pain control can often be improved by local (as opposed to systemic) application of analgesic and/or anesthetic medication. The purpose of this study was to evaluate the efficacy of a single-dose epidural analgesic “paste” in the control of postoperative pain in patients who have undergone lumbar decompressive surgery.

Methods. Sixty patients undergoing routine elective lumbar decompressive surgery were randomized in a double-blind fashion to one of two groups: those receiving active paste or placebo paste. The paste was applied to the exposed dura at the time of surgery, just prior to wound closure. Patients received follow-up care in the hospital and at home for 3 months postsurgery. Several outcome measures were studied to ascertain differences in pain control and to ensure comparability between groups. Patients who received active paste demonstrated significantly lower pain scores compared with those who received placebo paste for up to 6 weeks postoperatively. General health perception indexed by the Short Form 36 was also significantly better in patients who received active paste for up to 6 weeks. In-hospital and outpatient oral narcotic consumption was significantly lower in the active paste-treated group. Inpatient straight leg raising scores were improved in those patients who received active compared with control paste.

Conclusions. Application of an analgesic paste directly to the epidural space during lumbar decompressive surgery significantly improves postoperative pain control, reduces prescribed analgesic drug consumption, and improves overall health perception for up to 6 weeks following surgery. The authors conclude that this postoperative pain control strategy is both effective and safe and may provide a new standard of pain management in patients undergoing lumbar discectomy or laminectomy.
Variations of the extreme-lateral craniocervical approach: anatomical study and clinical analysis of 69 patients
Authors: Salas Eduardo , Sekhar Laligam N. , Ziyal Ibrahim M. , Caputy Anthony J. , Wright Donald C.
Published: May 2009

Object. The aim of this study was to describe six variations of the extreme-lateral craniocervical approach, their application, and treatment results.

Methods. During a 4-year period 69 patients underwent surgery in which six variations of the extreme-lateral craniocervical approach were performed. The variations included: the transfacetal approach (TFA), performed to treat four lesions in the upper cervical spine anterior or anterolateral to the spinal cord; the retrocondylar approach, to treat five intradural lesions located anterolateral to the medulla oblongata and six vascular lesions to expose the extradural segment of the vertebral artery (VA); the partial transcondylar approach (PTCA), to treat 18 intradural lesions located anterior to the medulla oblongata; the complete transcondylar approach (CTCA), to treat 13 extradural lesions that involved the lower clivus and anterior upper cervical spine; the extreme-lateral transjugular approach, to treat 14 jugular foramen tumors; and the transtubercular approach with or without division of the sigmoid sinus, to treat complex VA and vertebrobasilar junction aneurysms. An anatomical prosection was performed to study the surgical exposure of each of the six variations of the extreme-lateral craniocervical approach.

Total removal was achieved in 35 (69%) of the patients with tumor; subtotal resection was achieved in 16 (31%) of those patients. In the 12 patients with VA aneurysms, seven underwent clipping, three underwent trapping and a vein graft bypass procedure, and two underwent trapping without the use of a bypass procedure. In five other patients, different cystic, inflammatory, and other vascular lesions were successfully treated. Fifty percent of the patients who underwent surgery via the TFA, 83% via the of the CTCA, and 11% via the PTCA required an occipitocervical fusion procedure. The mean Karnofsky Performance Scale score was 74.7 preoperatively and 76.4 postoperatively. Major complications were hydrocephalus (nine patients), cerebrospinal fluid leakage (seven patients), worsened cranial nerve function (seven patients), vertebrobasilar vasospasm (one patient), and sigmoid sinus thrombosis (one patient).

Conclusions. To treat lesions in the region of the foramen magnum and surrounding areas, the approach should be tailored to each specific lesion to provide the needed exposure without unnecessary operative steps.
Vascular endothelial growth/permeability factor in spinal cord injury
Authors: Vaquero Jesús , Zurita Mercedes , de Oya Santiago , Coca Santiago
Published: May 2009

Object. Predicated on the hypothesis that this cytokine can contribute to the development of vascular hyperpermeability, leading to tissue edema after trauma, the purpose of this study was to determine the presence in tissue of vascular endothelial growth/permeability factor (VEG/PF) after experimental spinal cord injury.

Methods. The presence of VEG/PF was studied at 8 hours and 2, 8, and 14 days after a traumatic injury in adult Wistar rats. Studies were conducted in which a monoclonal antibody to the VEG/PF was used. Strong VEG/PF immunoreactivity was detected in the walls of pial and intramedullary vessels and in reactive astrocytes 8 hours posttrauma and was unchanged on Days 2 and 8. By Day 14, immunoreactivity decreased, and most of the arterioles from the pia and gray matter showed no mural VEG/PF.

Conclusions. The authors' present findings suggest a role for this cytokine in the development of tissue edema after spinal cord trauma and point to the possible usefulness of a therapeutic approach to spinal cord injury based on blocking the cell expression of VEG/PF or its physiological effects.
Use of porous hydroxyapatite graft containing recombinant human bone morphogenetic protein-2 for cervical fusion in a caprine model
Authors: Takahashi Toshiyuki , Tominaga Teiji , Watabe Noriaki , Yokobori A. Toshimitu , Sasada Hiroshi , Yoshimoto Takashi
Published: May 2009

Object. The efficacy of recombinant human bone morphogenetic protein-2 (rhBMP-2) for enhancing anterior cervical spine interbody fusion when added to a porous hydroxyapatite (HA) graft was investigated.

Methods. Fourteen mature goats underwent three-level anterior discectomies after induction of endotracheal anesthesia. Porous HA grafts that contained 0, 5, and 50 µg of rhBMP-2 were placed concurrently with anterior cervical spine plates to achieve interbody fusion. The fusion rate, radiological findings, biomechanical stiffness, and histological appearance were evaluated in 42 spinal units immediately and again at 4 and 12 weeks after graft and plate placement.

At 12 weeks postsurgery, manual testing showed a 100% fusion rate in the spines with HA grafts containing high-dose rhBMP-2; however, only a 50% fusion rate was shown in spines with grafts that contained no or low-dose rhBMP-2. On radiographic and histological studies the process of solid fusion was seen to be more advanced in relation to the use of larger amounts of rhBMP-2. Biomechanical testing demonstrated significantly higher stiffness values for grafts that contained high-dose rhBMP-2 than those without rhBMP-2 in flexion at 4 weeks, as well as in flexion, extension, and lateral bending tests at 12 weeks. Histological analysis demonstrated that rhBMP-2 increased the amount of bone apposition on the surface of the implants and promoted bone formation in the porous structure without increasing the penetration distance.

Conclusions. Through osteogenesis at the fusion site, the addition of rhBMP-2 to a porous HA ceramic graft enhances the rate of anterior cervical fusion.
Neurocytoma of the cauda equina
Authors: Stephan Christina L. , Kepes John J. , Arnold Paul , Green K. Douglas , Chamberlin Fran
Published: May 2009

✓ A case of a neurocytoma involving a nerve root of the cauda equina in a 46-year-old woman is reported. The patient presented with a 2-month history of progressive left lower-extremity weakness and pain and decreased ability to walk, as well as complaints of incomplete voiding. A magnetic resonance image revealed a 7-mm oval mass that was located intrathecally and extended from T-12 to L-1 and was adjacent to a nerve root. No lesions were identified at higher vertebral levels. The mass was excised. On histological examination it was found to have classical features of a neurocytoma. To the best of the authors' knowledge, this is the first report of a neurocytoma occurring in that region. A detailed histological description of this case and review of the pertinent literature are provided.
A new occipitocervical fusion construct in pediatric patients with occipitocervical instability
Authors: Brockmeyer Douglas L. , Apfelbaum Ronald I.
Published: May 2009

✓ Posterior occipitocervical stabilization procedures were successfully performed in 10 patients (nine boys and one girl) 16 years of age or younger by using C1–2 transarticular screws coupled with a rigid occipitocervical construct. The average length of follow-up evaluation was 18.8 months (range 5–37 months). No implant failed and all fusions were successful without the use of an external orthotic halo device.
A new type of microelectrode for obtaining unitary recordings in the human spinal cord
Authors: Guenot Marc , Hupe Jean-Michel , Mertens Patrick , Ainsworth Alan , Bullier Jean , Sindou Marc
Published: May 2009

Object. In this paper the authors report on the conception and adjustment of a microelectrode used to obtain unitary recordings in the human spinal cord.

Methods. To overcome the difficulties related to intraoperative pulsations of the spinal cord, the authors opted to use a floating microelectrode. Because the recordings are obtained most often from spontaneous activities, it is difficult, with a single microelectrode, to separate spikes from electrical artifacts that are related to the switching of devices. Consequently, the authors designed a dual microelectrode made of two tungsten-in-glass—attached microelectrodes separated by 300 µm. Because the two electrodes cannot obtain recordings in the same neuron, it is possible to distinguish unambiguously spikes (recorded on one tip) from electrical artifacts (recorded simultaneously on the two tips). The dual microelectrode is 2 cm long, with a 20-µm tip length, and 800 to 1200—Ohms impedance. This microelectrode can be implanted “free hand,” in the dorsal horn, by using a microsurgical forceps under a surgical microscope. The data analysis is performed off-line with spike sorter hardware.

In the dorsal horns in 17 patients who were selected to undergo a dorsal root entry zone (DREZ) rhizotomy to treat various pathological conditions, unitary recordings were obtained using this double microelectrode. The authors recorded 57 neurons in good conditions of stability and isolation.

Conclusions. The microelectrode described in this paper was successfully used to obtain recordings in neurons in more than 85% of the patients. This simplified, floating double microelectrode can therefore be considered for use in microsurgical DREZ rhizotomy to obtain unitary recordings in the human spinal dorsal horn.
Artificial lamina-assisted laminoplasty performed in seven cases
Authors: Fornari Maurizio , Luccarelli Giovanni , Giombini Sergio , Chiapparini Luisa
Published: May 2009

Object. The authors attempted to simplify the operative approach to severe multilevel cervical spondylotic myelopathy. Seven patients with progressive and severe myelopathy underwent modified double-door laminoplasty during a 5-month period.

Methods. The double-door laminoplasty procedure was modified by using two artificial titanium laminae obtained by simple surgical 0.5-mm Ti-mesh (rather than by bone graft or ceramic spacers).

Preoperatively, gait disturbance was present in all patients with long-tract signs on neurological examination. In all cases the sagittal diameter of the cervical spinal canal was somewhat reduced (< 10 mm) by congenital stenosis, and further severe compression of the spinal cord resulted from osteophytic bars and calcified ligamenta flava at different levels. No abnormal alignment, pathological movements, or instability was present. Computerized tomography (CT) studies demonstrated severe multilevel cervical compression, and T2-weighted magnetic resonance (MR) imaging demonstrated pathological areas of hyperintensity within the spinal cord in all cases.

In the initial follow-up study (range 8–12 months), the patients who underwent this procedure experienced marked improvement of gait disturbance without any significant incidence of morbidity or complications. Postoperative CT and MR imaging studies demonstrated complete spinal cord decompression and restoration of the patency of the subarachnoid spaces.

Conclusions. The proposed procedure has the advantage of achieving both an immediate stabilization of the open laminae by means of a bridgelike mechanism and protection from the possible compression of the dural sac by paravertebral muscles.