bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trigeminocardiac reflex during surgery in the cerebellopontine angle
Authors: Schall Bernhard , Probst Rudolf , Strebel Stephan , Fuhr Peter , Gratzl Otmar 
Published: January 2008

In different experimental studies authors have analyzed the autonomic responses elicited by the electrical, mechanical, or chemical stimulation of the trigeminal nerve system. The trigeminocardiac reflex (TCR) is a well-recognized phenomenon that consists of bradycardia, arterial hypotension, apnea, and gastric hypermotility. It occurs during ocular surgery and during other manipulations in and around the orbit. Thus far, it has not been shown that central stimulation of the trigeminal nerve can also cause this reflex.
The TCR was defined as clinical hypotension with a drop in mean arterial blood pressure (MABP) of more than 20% and bradycardia lower than 60 beats/minute. Pre-, intra-, and postoperative heart rate (HR) and blood pressure were reviewed retrospectively in 125 patients who underwent surgery for tumors of the cerebellopontine angle (CPA), and they were divided into a TCR group and a non-TCR group. Of the 125 patients, 14 (11%) showed evidence of TCR during dissection of the tumor near the trigeminal nerve at the brainstem. Their HR fell 38% and their MABP fell 48% during operative procedures as compared with preoperative levels. After cessation of manipulation, the HR and the MABP returned to preoperative levels. Risk factors for the occurrence of TCR were compared with results from the literature.
The authors' results show the possibility of occurrence of a TCR during manipulation of the central part of the trigeminal nerve when performing surgery in the CPA.
Facial nerve injury in acoustic neuroma (vestibular schwannoma) surgery: etiology and prevention
Authors: Sampath Prakash , Holliday Michael J. , Brem Henry , Niparko John K. , Long Donlin M. 
Published: January 2008

Facial nerve injury associated with acoustic neuroma surgery has declined in incidence but remains a clinical concern. A retrospective analysis of 611 patients surgically treated for acoustic neuroma between 1973 and 1994 was undertaken to understand patterns of facial nerve injury more clearly and to identify factors that influence facial nerve outcome.
Anatomical preservation of the facial nerve was achieved in 596 patients (97.5%). In the immediate postoperative period, 62.1% of patients displayed normal or near-normal facial nerve function (House-Brackmann Grade 1 or 2). This number rose to 85.3% of patients at 6 months after surgery and by 1 year, 89.7% of patients who had undergone acoustic neuroma surgery demonstrated normal or near-normal facial nerve function.
The surgical approach appeared to have no effect on the incidence of facial nerve injury. Poor facial nerve outcome (House-Brackmann Grade 5 or 6) was seen in 1.58% of patients treated via the suboccipital approach and in 2.6% of patients treated via the translabyrinthine approach. When facial nerve outcome was examined with respect to tumor size, there clearly was an increased incidence of facial nerve palsy seen in the immediate postoperative period in cases of larger tumors: 60.8% of patients with tumors smaller than 2.5 cm had normal facial nerve function, whereas only 37.5% of patients with tumors larger than 4 cm had normal function. This difference was less pronounced, however, 6 months after surgery, when 92.1% of patients with tumors smaller than 2.5 cm had normal or near normal facial function, versus 75% of patients with tumors larger than 4 cm.
The etiology of facial nerve injury is discussed with emphasis on the pathophysiology of facial nerve palsy. In addition, on the basis of the authors' experience with these complex tumors, techniques of preventing facial nerve injury are discussed.
Arteriovenous malformation in association with moyamoya disease
Authors: Nakashima Toshihiko , Nakayama Noriyuki , Furuichi Masahiro , Kokuzawa Jouji , Murakawa Takatsugu , Sakai Noboru 
Published: January 2008

The authors report two rare cases of arteriovenous malformation (AVM) associated with moyamoya disease. An AVM, supplied by transdural communicating arteries, was located in the right occipital lobe in one patient who presented with ischemia. The second AVM, which was supplied by basal moyamoya vessels, was located in the posterior part of the left frontal lobe in a patient who developed intracerebral hemorrhage that occupied the left basal ganglion.
A review of the literature revealed a total of 12 AVMs in 11 patients with moyamoya disease including our cases. All AVMs were cerebral and two were supplied by normal cerebral arteries, whereas six AVMs were supplied by basal moyamoya vessels at the base of the brain and four AVMs were supplied by external carotid arteries through the transdural communicating arteries. Every AVM drained into deep or cortical cerebral veins. These findings suggest that the hyperangiogenic character of moyamoya disease occasionally induces the development of acquired arteriovenous shunts that mimic AVM.
Sylvian aqueduct syndrome and global rostral midbrain dysfunction associated with shunt malfunction
Authors: Cinalli Giuseppe , Sainte-Rose Christian , Simon Isabelle , Lot Guillaume , Sgouros Spiros 
Published: January 2008

Object
This study is a retrospective analysis of clinical data obtained in 28 patients affected by obstructive hydrocephalus who presented with signs of midbrain dysfunction during episodes of shunt malfunction.

Methods
All patients presented with an upward gaze palsy, sometimes associated with other signs of oculomotor dysfunction. In seven cases the ocular signs remained isolated and resolved rapidly after shunt revision. In 21 cases the ocular signs were variably associated with other clinical manifestations such as pyramidal and extrapyramidal deficits, memory disturbances, mutism, or alterations in consciousness. Resolution of these symptoms after shunt revision was usually slow. In four cases a transient paradoxical aggravation was observed at the time of shunt revision. In 11 cases ventriculocisternostomy allowed resolution of the symptoms and withdrawal of the shunt.
Simultaneous supratentorial and infratentorial intracranial pressure recordings performed in seven of the patients showed a pressure gradient between the supratentorial and infratentorial compartments with a higher supratentorial pressure before shunt revision. Inversion of this pressure gradient was observed after shunt revision and resolution of the gradient was observed in one case after third ventriculostomy. In six recent cases, a focal midbrain hyperintensity was evidenced on T2-weighted magnetic resonance imaging sequences at the time of shunt malfunction. This rapidly resolved after the patient underwent third ventriculostomy.
It is probable that in obstructive hydrocephalus at the time of shunt malfunction, the development of a transtentorial pressure gradient could initially induce a functional impairment of the upper midbrain, inducing upward gaze palsy. The persistence of the gradient could lead to a global dysfunction of the upper midbrain.

Conclusions
Third ventriculostomy contributes to equalization of cerebrospinal fluid pressure across the tentorium by restoring free communication between the infratentorial and supratentorial compartments, resulting in resolution of the patient's clinical symptoms.
Apoptosis after traumatic human spinal cord injury
Authors: Emery Evelyne , Aldana Philipp , Bunge Mary Bartlett , Puckett William , Srinivasan Anu , Keane Robert W. , Bethea John , Levi Allan D. O. 
Published: January 2008

Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated.
The authors examined the spinal cords of 15 patients who died between 3 hours and 2 months after a traumatic SCI. Apoptotic cells were found at the edges of the lesion epicenter and in the adjacent white matter, particularly in the ascending tracts, by using histological (cresyl violet, hematoxylin and eosin) and nuclear staining (Hoechst 33342). The presence of apoptotic cells was supported by staining with the terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labeling technique and confirmed by immunostaining for the processed form of caspase-3 (CPP-32), a member of the interleukin-1-beta-converting enzyme/Caenorhabditis elegans D 3 (ICE/CED-3) family of proteases that plays an essential role in programmed cell death. Apoptosis in this series of human SCIs was a prominent pathological finding in 14 of the 15 spinal cords examined when compared with five uninjured control spinal cords. To determine the type of cells undergoing apoptosis, the authors immunostained specimens with a variety of antibodies, including glial fibrillary acidic protein, 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase), and CD45/68. Oligodendrocytes stained with CNPase and a number of apoptotic nuclei colocalized with positive staining for this antibody.
These results support the hypothesis that apoptosis occurs in human SCIs and is accompanied by the activation of caspase-3 of the cysteine protease family. This mechanism of cell death contributes to the secondary injury processes seen after human SCI and may have important clinical implications for the further development of protease inhibitors to prevent programmed cell death.
Magnetic resonance imaging-monitored conservative management of traumatic spinal epidural hematomas
Authors: La Rosa Giovanni , d'Avella Domenico , Conti Alfredo , Cardali Salvatore , La Torre Domenico , Cacciola Fabio , Longo Marcello , Tomasello Francesco 
Published: January 2008

Spinal epidural hematomas (SEHs) are uncommon complications caused by traumatic injuries to the spine. Emergency surgical evacuation is the standard treatment. Although recognized in the literature, the possibility of nonsurgical treatment of traumatic SEHs is far from being codified. The authors report on the treatment of four patients whose traumatic SEHs were diagnosed by magnetic resonance (MRI) imaging and managed conservatively with excellent results.
All patients had suffered severe spine injury with fracture of a lumbar vertebral body, were admitted within 12 hours of trauma, and exhibited only minimal neurological disturbances on admission. Magnetic resonance imaging studies were performed within 24 hours of trauma. Hematomas appeared isointense/slightly hyperintense on T1- and heterogeneous on T2-weighted MR images. Clot thickness varied between 0.8 cm and 1 cm, width between 1 cm and 1.8 cm, and length between 2.7 and 9 cm. In light of each patient's fairly good neurological condition a conservative approach was taken. In all cases serial MR imaging documented progressive clot resolution, which was completed within 8 to 10 days of trauma. At discharge all patients were neurologically intact.
The conservative treatment option of traumatic SEH should be reserved for exceptional cases whose deficits are minimal, when neurological deterioration is followed by early and sustained spontaneous recovery, and when there are clear medical contraindications for surgery. The results of the present study confirm that nonsurgical treatment is feasible in a subgroup of minimally symptomatic patients who harbor moderate-sized SEHs. Although the authors' experience shows a good spontaneous outcome of some traumatic SEH, further studies are necessary to understand the real spectrum of nonsurgical treatment of such lesions.
Surgery in epilepsy associated with focal lesions in childhood
Authors: Bourgeois Marie , Sainte-Rose Christian , Lellouch-Tubiana Arielle , Malucci Conor , Brunelle Francis , Maixner Wirginia , Cinalli Giuseppe , Pierre-Kahn Alain , Renier Dominique , Zerah Michel , Hirsch Jean-François , Goutières Francoise , Aicardi Jean 
Published: January 2008

Surgery in children with epilepsy is a new, evolving field. The important practical issues have been to define strategies for choosing the most suitable candidates, as well as the type and the optimum timing of epilepsy surgery. This study was undertaken to illustrate these points.
To identify the factors that correlated with outcome, the authors analyzed a series of 200 children (aged 1–15 years, mean 8.7 years) who underwent surgery at the Hôpital Necker-Enfants Malades between 1981 and 1996. In 171 cases (85.5%) the epilepsy was medically refractory and was associated with focal cortical lesions. Surgery consisted of resection of the lesion without specifically attempting to identify and remove the "epileptogenic area."
In the group of children whose seizures were medically refractory, the mean follow-up period was 5.8 years. According to Engel's classification, 71.3% of these children became seizure free (Ia), whereas 82% were in Class I. A multivariate statistical analysis revealed that among all the factors studied, the success of surgery in a patient in whom there was a good clinical-electroencephalogram-imaging correlation, depended on the patients' having undergone a minimally traumatic operation, a complete resection of the lesion, and a short preoperative seizure duration.
After the surgical control of epilepsy, behavior disorders were more improved (31% of all patients) than cognitive function (25%). The patient age at onset, duration and frequency of seizures, intractability of the disease to therapy, and seizure characteristics, were correlated with cognitive, behavioral, and academic performance pre- and postoperatively. Multivariate statistical analysis revealed that cognitive dysfunction correlated highly with the duration of epilepsy prior to surgery, whereas behavioral disorders correlated more with seizure frequency.
These data must be taken into account when selecting patients for surgical treatment and when deciding the timing of surgery. Early surgical intervention allows for optimum brain development.
A mobile high-field magnetic resonance imaging system for neurosurgery
Authors: Sutherland Garnette R. , Kaibara Taro , Louw Deon , Saunders John 
Published: January 2008

The authors' goal was to place a mobile, 1.5 tesla magnetic resonance (MR) imaging system into a neurosurgical operating room without adversely affecting established neurosurgical management. The system would help to plan accurate surgical corridors, confirm the accomplishment of operative objectives, and detect acute complications such as hemorrhage or ischemia.
The authors used an actively shielded 1.5 tesla magnet, together with 15 m tesla/m gradients, MR console computers, gradient amplifiers, a titanium, hydraulic-controlled operating table, and a radio frequency coil that can be disassembled. The magnet is moved to and from the surgical field by using overhead crane technology. To date, the system has provided unfettered access to 46 neurosurgical patients.
In all patients, high-definition T1- and/or T2-weighted images were rapidly and reproducibly acquired at various stages of the surgical procedures. Eleven patients underwent craniotomy that was optimized after pre-incisional imaging. In four patients who harbored subtotally resected tumor, intraoperative MR imaging allowed removal of remaining tumor. Interestingly, the intraoperative administration of gadolinium in the management of patients with malignant glioma demonstrated a dynamic expansion of enhancement beyond the preoperative contrast contour. These zones of new enhancement proved, on examination of biopsy sample, to be tumor.
The authors have demonstrated that high-quality MR images can be obtained within reasonable time constraints in the operating room. Procedures can be conducted without compromising or altering traditional neurosurgical, nursing, or anesthetic techniques. It is feasible that within the next decade intraoperative MR imaging may become the standard of care in neurosurgery.
Neuroendoscopic approach to intraventricular lesions
Authors: Gaab Michael R. , Schroeder Henry W. S. 
Published: January 2008

Object
The purpose of this study was to determine the efficacy of endoscopic treatment in patients with intraventricular tumors.

Methods
A series of 30 patients with endoscopically treated intraventricular lesions is reported. The lesions included seven colloid cysts, six astrocytomas, three subependymomas, two ependymomas, and one each of the following: pineoblastoma, pineocytoma/pineoblastoma (intermediate type), epidermoid cyst, pineal cyst, medulloblastoma, arteriovenous hemangioma, cavernoma, choroid plexus papilloma, pituitary adenoma, craniopharyngioma, melanoma, and germinoma. Total tumor resections, partial resections, biopsies, stent implantations, septostomies, and third ventriculostomies were performed. In two cases (two subependymomas > 2 cm in diameter), piecemeal endoscopic resection was ineffective because of the very firm consistency of the tumors. Therefore the endoscopic procedure was discontinued and the tumors were removed microsurgically. In the remaining cases the procedures were completed as planned. Even in the presence of difficulties such as poor orientation or significant bleeding, there was no need to abandon the endoscopic procedure. A total of 28 strictly endoscopic interventions were performed, in which the average duration was 85 minutes (range 35–170 minutes). All colloid cysts and the epidermoid lesion were completely evacuated and the capsules were widely resected. Total extirpation of solid tumors was achieved in five cases, whereas most astrocytomas were partially resected. The hydrocephalus-related symptoms resolved in all of the 22 patients with cerebrospinal fluid pathway obstruction. There were no endoscopy-related deaths. In two cases, major bleeding occurred and was controlled endoscopically. The authors observed one case of meningitis, one of mutism, two of memory loss attributed to forniceal injury, one of transient trochlear palsy after a biopsy specimen of an aqueductal tumor was obtained, and one of transient confusion after a biopsy specimen of a germinoma was obtained.

Conclusions
In the authors' preliminary experience, the endoscopic approach was found to be safe and effective. In this series, it was possible to achieve relief of noncommunicating hydrocephalus, tumor resections, and even complete tumor removals by using endoscopic techniques. Based on the results, the authors believe that endoscopic techniques should be considered in the treatment of selected intraventricular lesions.
Characterization of a model of hydrocephalus in transgenic mice
Authors: Cohen Alan R. , Leifer David , Zechel Marc , Flaningan Daniel P. , Lewin Jonathan S. , Lust W. David 
Published: January 2008

The purpose of this study was to elucidate the pathophysiology of hydrocephalus in a new transgenic model of mice created to overproduce the cytokine, transforming growth factor-ß1 (TGFß1), in the central nervous system (CNS).
Galbreath and colleagues generated transgenic mice that overexpressed TGFß1 in the CNS in an effort to examine the role of this cytokine in the astrocytic response to injury. Unexpectedly, the animals developed severe hydrocephalus and died. The authors perpetuated this transgenic colony to serve as a model of congenital hydrocephalus, breeding asymptomatic carrier males that were heterozygous for the transgene with wild-type females.
One hundred twelve (49.6%) of 226 mice developed clinical manifestations of hydrocephalus, which was characterized by dorsal doming of the calvaria, spasticity, limb tremors, ataxia, and ultimately death. The presence of the TGFß1 transgene was determined by performing polymerase chain reaction (PCR) analysis of sample cuts of tail. The animals with the hydrocephalic phenotype consistently carried the transgene, although some animals with the transgene did not develop hydrocephalus. Animals without the transgene did not develope hydrocephalus.
Alterations in brain structure were characterized using magnetic resonance (MR) imaging, gross and light microscopic analysis, and immunocytochemistry. Magnetic resonance imaging readily distinguished hydrocephalic animals from nonhydrocephalic controls, and it demonstrated an obstruction at the outlets of the fourth ventricle. Gross and light microscopic examination confirmed the MR findings. The results of immunofluorescent staining of brain tissue slices revealed the presence of the TGFß1 cytokine and its receptor preferentially in the meninges and subarachnoid space in both hydrocephalic and control mice. Reverse transcriptase-PCR analysis demonstrated tissue-specific expression of the TGFß1 gene in the brains of transgenic mice, and enzyme-linked immunosorbent assay confirmed the occurrence of overexpression of the TGFß1 cytokine in brain, cerebrospinal fluid, and plasma.
The transgenic murine model provides a reproducible representation of congenital hydrocephalus. The authors hypothesize that overexpression of TGFß1 in the CNS causes hyrdocephalus by altering the environment of the extracellular matrix and interfering with the circulation of cerebrospinal fluid. A model of hydrocephalus in which the genetic basis is known should be useful for evaluating hypotheses regarding the pathogenesis of this disorder and additionally, should help in the search for novel treatment strategies.
Microendoscopic posterior cervical foraminotomy: a cadaveric model and clinical application for cervical radiculopathy
Authors: Burke Timothy G. , Caputy Anthony 
Published: January 2008

Cervical radiculopathy that is caused by either soft herniated disc material or foraminal stenosis is a common problem. Anterior and posterior surgical approaches are commonly performed to decompress the nerve root. The authors describe an endoscopic posterior foraminotomy procedure in which they use a rigid endoscope, in both a cadaveric model and in three clinical cases, including a multiple level case.
Postoperatively, all patients returned to functional work status within 4 weeks. The mean length of hospitalization was 1.3 days.
The advantages of this technique include improved visualization, a smaller incision, and significantly less postoperative discomfort when compared with a matched group of patients in whom open nonendoscopic foraminotomy has been performed.