bluuebunny/crossref_metadata_2025 huggingface dataset:
Tumors of the endolymphatic sac in patients with von Hippel—Lindau disease: implications for their natural history, diagnosis, and treatment
Authors: Kim H. Jeffrey , Butman John A. , Brewer Carmen , Zalewski Christopher , Vortmeyer Alexander O. , Glenn Gladys , Oldfield Edward H. , Lonser Russell R.
Published: May 2009

Object. Endolymphatic sac tumors (ELSTs), which often are associated with von Hippel—Lindau (VHL) disease, cause irreversible hearing loss and vestibulopathy. Clinical and imaging surveillance protocols provide new insights into the natural history, mechanisms of symptom formation, and indications for the treatment of ELSTs. To clarify the uncertainties associated with the pathophysiology and treatment of ELSTs, the authors describe a series of patients with VHL disease in whom serial examinations recorded the development of ELSTs.

Methods. Patients with VHL disease were included if serial clinical and imaging studies captured the development of ELSTs, and the patients underwent tumor resection. The patients' clinical, audiological, and imaging characteristics as well as their operative results were analyzed.

Five consecutive patients (three men and two women) with a mean age at surgery of 34.8 years and a follow-up period of 6 to 18 months were included in this study. Audiovestibular symptoms were present in three patients before a tumor was evident on neuroimaging. Imaging evidence of an intralabyrinthine hemorrhage coincided with a loss of hearing in three patients. Successful resection of the ELSTs was accomplished by performing a retrolabyrinthine posterior petrosectomy (RLPP). Hearing stabilized and vestibular symptoms resolved after surgery in all patients. No patient has experienced a recurrence.

Conclusions. Audiovestibular symptoms, including hearing loss, in patients with VHL disease can be the result of microscopic ELSTs. Once an ELST has been detected, it can be completely resected via an RLPP with preservation of hearing and amelioration of vestibular symptoms. Early detection and surgical treatment of small ELSTs, when hearing is still present, should reduce the incidence and severity of hearing loss, tinnitus, vertigo, and cranial nerve dysfunction, which are associated with these tumors.
Selective ablation of nociceptive neurons for elimination of hyperalgesia and neurogenic inflammation
Authors: Tender Gabriel C. , Walbridge Stuart , Olah Zoltan , Karai Laszlo , Iadarola Michael , Oldfield Edward H. , Lonser Russell R.
Published: May 2009

Object. Neuropathic pain is mediated by nociceptive neurons that selectively express the vanilloid receptor 1 (VR1). Resiniferatoxin (RTX) is an excitotoxic VR1 agonist that causes destruction of VR1-positive neurons. To determine whether RTX can be used to ablate VR1-positive neurons selectively and to eliminate hyperalgesia and neurogenic inflammation without affecting tactile sensation and motor function, the authors infused it unilaterally into the trigeminal ganglia in Rhesus monkeys.

Methods. Either RTX (three animals) or vehicle (one animal) was directly infused (20 µl) into the right trigeminal ganglion in Rhesus monkeys. Animals were tested postoperatively at 1, 4, and 7 weeks thereafter for touch and pain perception in the trigeminal distribution (application of saline and capsaicin to the cornea). The number of eye blinks, eye wipes, and duration of squinting were recorded. Neurogenic inflammation was tested using capsaicin cream. Animals were killed 4 (one monkey) and 12 (three monkeys) weeks postinfusion. Histological and immunohistochemical analyses were performed.

Throughout the duration of the study, response to high-intensity pain stimulation (capsaicin) was selectively and significantly reduced (p < 0.001, RTX-treated compared with vehicle-treated eye [mean ± standard deviation]): blinks, 25.7 ± 4.4 compared with 106.6 ± 20.8; eye wipes, 1.4 ± 0.8 compared with 19.3 ± 2.5; and squinting, 1.4 ± 0.6 seconds compared with 11.4 ± 1.6 seconds. Normal response to sensation was maintained. Animals showed no neurological deficit or sign of toxicity. Neurogenic inflammation was blocked on the RTX-treated side. Immunohistochemical analysis of the RTX-treated ganglia showed selective elimination of VR1-positive neurons.

Conclusions. Nociceptive neurons can be selectively ablated by intraganglionic RTX infusion, resulting in the elimination of high-intensity pain perception and neurogenic inflammation while maintaining normal sensation and motor function. Analysis of these findings indicated that intraganglionic RTX infusion may provide a new treatment for pain syndromes such as trigeminal neuralgia as well as others.
Glioblastoma multiforme metastasis to the axis
Authors: Utsuki Satoshi , Tanaka Satoshi , Oka Hidehiro , Iwamoto Kazuhisa , Sagiuchi Takao , Fujii Kiyotaka
Published: May 2009

✓ Extracranial bone metastasis from glioblastoma multiforme (GBM) has rarely been reported in the literature, and most metastatic GBMs are multiple bone metastases. The authors describe the first case of a GBM with metastasis only to the axis. This 42-year-old man presented with a 2-month history of headache, nausea, vomiting, and disorientation. Magnetic resonance imaging demonstrated a right temporal tumor, which was diagnosed as a GBM based on tumor resection. The patient was treated using radiation (6000 cGy) and the intravenous administration of nimustine hydrochloride. Eighteen months thereafter, he experienced the sudden onset of neck pain. Magnetic resonance studies revealed a tumor in the axis that was diagnosed as GBM based on biopsy procedure.
Rosai—Dorfman disease with dural sinus invasion
Authors: Toh Cheng-Hong , Chen Yao-Liang , Wong Ho-Fai , Wei Kuo-Chen , Ng Shu-Hang , Wan Yung-Liang
Published: May 2009

✓ Rosai—Dorfman disease (RDD) is an idiopathic proliferation of histiocytes that affects the lymph nodes. Central nervous system involvement in the absence of nodal disease is extremely rare. On neuroimaging studies, intracranial RDD appears as solitary or multiple well-circumscribed, dura-based lesions. The authors report on two cases of RDD with locally aggressive features including dural sinus invasion, which to their knowledge has never before been described.

A 60-year-old woman presented with progressive dizziness and vertigo that had lasted for 1 week. Cranial computerized tomography and magnetic resonance imaging revealed an extraaxial homogeneous lobulated enhancing mass involving the right occipital lobe and the right cerebellar hemisphere. Invasion of the right transverse sinus was identified on a cerebral digital subtraction angiogram. A 59-year-old man with no prior medical illness experienced progressive weakness of both upper extremities and a partial complex seizure. Magnetic resonance imaging of his brain revealed a well-circumscribed enhancing mass in the left frontal lobe with extension to the right frontal lobe and invasion of the superior sagittal sinus. Both patients underwent resection of their brain masses. Pathological studies identified the disease as RDD in both patients.
Endovascular management of traumatic and iatrogenic aneurysms of the pericallosal artery
Authors: Cohen José E. , Rajz Gustavo , Itshayek Eyal , Shoshan Yigal , Umansky Felix , Gomori John M.
Published: May 2009

✓ Traumatic intracranial aneurysms are rare complications of closed and penetrating head injuries and may also be related to a variety of neurosurgical procedures. The primary goals in the treatment of patients harboring these lesions are early identification and intervention to prevent bleeding. Traumatic aneurysms are fragile, prone to rupture, and represent a challenging subset of vascular lesions for either surgery or endovascular therapy. Surgical approaches to aneurysms located at the pericallosal arteries are associated with higher rates of morbidity and mortality than approaches to other supratentorial aneurysms. Current endovascular treatment most often involves occlusion of the parent artery with the potential of added morbidity. The authors present their experience in the endovascular management of traumatic and iatrogenic aneurysms of the pericallosal artery achieved by primary coil embolization with parent vessel preservation. For patients harboring traumatic pericallosal aneurysms with favorable anatomical characteristics, in which the morbidity caused by parent vessel occlusion is not acceptable, endosaccular coil placement may be a valuable option.
Endovascular coil embolization of intracranial aneurysms: important factors related to rates and outcomes of incomplete occlusion
Authors: Kole Max K. , Pelz David M. , Kalapos Paul , Lee Donald H. , Gulka Irene B. , Lownie Stephen P.
Published: May 2009

Object. The authors report on important factors that influenced clinical and angiographically demonstrated outcomes in patients treated using coil embolization.

Methods. This study included 160 consecutive patients who underwent endovascular coil embolization for treatment of intracranial aneurysms. Univariate and multivariate logistic regression analyses were performed to assess factors that influenced the immediate posttreatment angiographic result. Cox regression analysis was used to establish factors related to the occurrence of negative events as well as a curve indicating the time to a negative event. Negative events were defined as aneurysm remnant increase, repeated treatment, rebleeding, or death during periprocedural hospitalization.

Seventy-three percent of the patients treated in this study were independent or demonstrated no deficit (Glasgow Outcome Scale [GOS] Score 4 or 5) at a mean follow up of 18.2 months. The annual delayed rebleeding rate was 0.45%. Fifty percent of patients (65 of 131) suffered a negative event within 13 ± 14 months (standard deviation). Statistically significant factors associated with the occurrence of negative events were rupture status (p = 0.0128) and immediate posttreatment angiographic result (p < 0.001). Overall clinical outcome assessed using the GOS was significantly related to the immediate posttreatment angiographic result (χ2 = 4.788, p = 0.029). The immediate posttreatment angiographic results were significantly influenced by catheter stability (p = 0.0012), aneurysm geometry (that is, simple or complex, p = 0.0053), and aneurysm neck diameter (p = 0.0205).

Conclusions. A good or excellent clinical outcome can be obtained in most patients treated using endovascular coil embolization of intracranial aneurysms. Note, however, that a significant number of patients treated using traditional platinum coils will harbor unstable aneurysm remnants or require repeated treatment.
Safety of intracranial aneurysm surgery performed in a postgraduate training program: implications for training
Authors: Woodrow Sarah I. , Bernstein Mark , Wallace M. Christopher
Published: May 2009

Object. Patient care and educational experience have long formed a dichotomy in modern surgical training. In neurosurgery, achieving a delicate balance between these two factors has been challenged by recent trends in the field including increased subspecialization, emerging technologies, and decreased resident work hours. In this study the authors evaluated the experience profiles of neurosurgical trainees at a large Canadian academic center and the safety of their practice on patient care.

Methods. Two hundred ninety-three patients who underwent surgery for intracranial aneurysm clipping between 1993 and 1996 were selected. Prospective data were available in 167 cases, allowing the operating surgeon to be identified. Postoperative data and follow-up data were gathered retrospectively to measure patient outcomes. In 167 cases, a total of 183 aneurysms were clipped, the majority (91%) by neurosurgical trainees. Trainees performed dissections on aneurysms that were predominantly small (<1.5 cm in diameter; 77% of patients) and ruptured (64% of patients). Overall mortality rates for the patients treated by the trainee group were 4% (two of 52 patients) and 9% (nine of 100 patients) for unruptured and ruptured aneurysm cases, respectively. Patient outcomes were comparable to those reported in historical data. Staff members appeared to be primary surgeons in a select subset of cases.

Conclusions. Neurosurgical trainees at this institution are exposed to a broad spectrum of intracranial aneurysms, although some case selection does occur. With careful supervision, intracranial aneurysm surgery can be safely delegated to trainees without compromising patient outcomes. Current trends in practice patterns in neurosurgery mandate ongoing monitoring of residents' operative experience while ensuring continued excellence in patient care.
Prognostic significance of intracranial dissemination of glioblastoma multiforme in adults
Authors: Parsa Andrew T. , Wachhorst Scott , Lamborn Kathleen R. , Prados Michael D. , McDermott Michael W. , Berger Mitchel S. , Chang Susan M.
Published: May 2009

Object. The clinical outcome and treatment of adult patients with disseminated intracranial glioblastoma multiforme (GBM) is unclear. The objective in the present study was to assess the prognostic significance of disseminated intracranial GBM in adults at presentation and at the time of tumor progression.

Methods. Clinical data from 1491 patients older than 17 years and harboring a GBM that had been diagnosed between 1988 and 1998 at the University of California at San Francisco neurooncology clinic were retrospectively reviewed. Dissemination of the GBM (126 patients) was determined based on Gd-enhanced magnetic resonance images. Classification of dissemination was as follows: Type I, single lesion with subependymal or subarachnoid spread; Type II, multifocal lesions without subependymal or subarachnoid spread; and Type III, multifocal lesions with subependymal or subarachnoid spread. Subgroups of patients were compared using Kaplan—Meier curves that depicted survival probability.

The median postprogression survival (PPS), defined according to neuroimaging demonstrated dissemination, was 37 weeks for Type I (23 patients), 25 weeks for Type II (50 patients), and 10 weeks for Type III spread (19 patients). Patients with dissemination at first tumor progression (52 patients) overall had a shorter PPS than those in a control group with local progression, after adjusting for age, Karnofsky Performance Scale score, and time from tumor diagnosis to its progression (311 patients). When analyzed according to tumor dissemination type, PPS was significantly shorter in patients with Type II (33 patients, p < 0.01) and Type III spread (11 patients, p < 0.01) but not in those with Type I spread (eight patients, p = 0.18).

Conclusions. Apparently, the presence of intracranial tumor dissemination on initial diagnosis does not in itself preclude aggressive treatment if a patient is otherwise well. A single focus of GBM that later demonstrates Type I dissemination on progression does not have a worse prognosis than a lesion that exhibits only local recurrence.
Intraoperative auditory brainstem responses in patients with cerebellopontine angle meningiomas involving the inner auditory canal: analysis of the predictive value of the responses
Authors: Nakamura Makoto , Roser Florian , Dormiani Mehdi , Samii Madjid , Matthies Cordula
Published: May 2009

Object. Meningiomas of the cerebellopontine angle (CPA) can either arise from or secondarily grow into the inner auditory canal (IAC). This location may have a great impact on hearing function following surgery to remove these lesions. The aim of this retrospective study was to investigate the reliability and predictive importance of auditory brainstem responses (ABRs) for the determination of postoperative auditory function in patients with CPA meningiomas in comparison with results obtained in patients who undergo surgery for vestibular schwannomas.

Methods. In a consecutive series of 1800 meningiomas surgically treated between 1978 and 2002, 421 lesions were located in the CPA. In 38 patients with CPA meningiomas involving the IAC, the findings of intraoperative ABR monitoring and the hearing status of each patient before and after surgery were retrospectively analyzed.

On analysis, ABR monitoring demonstrated stable findings in 24 patients throughout tumor resection and fluctuating signals in 10 patients. Among the 24 patients with stable ABRs, postoperative hearing function improved in three patients, remained the same in 15, and worsened in six patients, including one patient who displayed postoperative deafness. There was even one patient recovering from preoperative deafness. Among the 10 patients with unstable ABRs, intermittent decreases in amplitude and deformations of variable duration in the ABR wave were noted. The risk of deafness was considerably higher in patients with prolonged phases of intermittent ABR deterioration.

Conclusions. The presence and absence of ABRs during surgery for CPA meningiomas reliably predicted the presence and absence of postoperative auditory function. Intermittent deterioration of ABRs may result in postoperative deafness, depending on the duration of these events during surgery. Improvements in hearing are only seen when the ABRs are stable for amplitudes and latencies throughout surgery.
Resection of large vestibular schwannomas: facial nerve preservation in the context of surgical approach and patient-assessed outcome
Authors: Anderson Douglas E. , Leonetti John , Wind Joshua J. , Cribari Denise , Fahey Karen
Published: May 2009

Object. Vestibular schwannoma surgery has evolved as new therapeutic options have emerged, patients' expectations have risen, and the psychological effect of facial nerve paralysis has been studied. For large vestibular schwannomas for which extirpation is the primary therapy, the goals remain complete tumor resection and maintenance of normal neurological function. Improved microsurgical techniques and intraoperative facial nerve monitoring have decreased the complication rate and increased the likelihood of normal to near-normal postoperative facial function. Nevertheless, the impairment most frequently reported by patients as an adverse effect of surgery continues to be facial nerve paralysis. In addition, patient assessment has provided a different, less optimistic view of outcome. The authors evaluated the extent of facial function, timing of facial nerve recovery, patients' perceptions of this recovery and function, and the prognostic value of intraoperative facial nerve monitoring following resection of large vestibular schwannomas; they then analyzed these results with respect to different surgical approaches.

Methods. The authors retrospectively reviewed a database of 67 patients with 71 vestibular schwannomas measuring 3 cm or larger in diameter. The patients had undergone surgery via translabyrinthine, retrosigmoid, or combined approaches. Clinical outcomes were analyzed with respect to intraoperative facial nerve activity, responses to intraoperative stimulation, and time course of recovery.

Eighty percent of patients obtained normal to near-normal facial function (House—Brackmann Grades I and II). Patients' perceptions of facial nerve function and recovery correlated well with the clinical observations.

Conclusions. Trends in the data lead the authors to suggest that a retrosigmoid exposure, alone or in combination with a translabyrinthine approach, offers the best chance of facial nerve preservation in patients with large vestibular schwannomas.
Long-term neurological, visual, and endocrine outcomes following transnasal resection of craniopharyngioma
Authors: Chakrabarti Indro , Amar Arun P. , Couldwell William , Weiss Martin H.
Published: May 2009

Object. The authors report on a cohort of patients with craniopharyngioma treated principally through transnasal (TN) resection and followed up for a minimum of 5 years. More specifically, they evaluate the role of the TN approach in the management of craniopharyngioma.

Methods. Between 1984 and 1994, 68 patients underwent TN resection of craniopharyngiomas at the University of Southern California. The tumor was at least partially cystic in 88% of cases. Four tumors were purely intrasellar, 53 had intra- and suprasellar components, and 11 were exclusively suprasellar. During the same period, 18 patients underwent transcranial (TC) resection of purely suprasellar craniopharyngiomas. Long-term neurological, visual, and endocrine outcomes were reviewed for all patients.

In 61 (90%) of 68 patients in the TN group, total resection was achieved, according to 3-month postoperative magnetic resonance images, although four patients suffered a recurrence. Three (43%) of the seven tumors that had been partially resected were enlarged on serial imaging. Fifty-four (87%) of 62 patients with preoperative visual loss experienced improvement in one or both eyes, but two patients (3%) with exclusively suprasellar tumors experienced postoperative visual worsening in one or both eyes. New instances of postoperative endocrinopathy (that is, not present preoperatively) occurred as follows: hypogonadism (eight of 22 cases), growth hormone (GH) deficiency (four of 18 cases), hypothyroidism (11 of 49 cases), hypocortisolemia (nine of 52 cases), and diabetes insipidus (DI; four of 61 cases). One case each of hypocortisolemia and hypothyroidism resolved after surgery. Hyperphagia occurred in 27 (40%) of 68 patients. One patient had short-term memory loss. Postoperative complications included one case of cerebrospinal fluid leak.

Among the 18 patients in the TC group, 11 had complete resections. In one case (9%) the tumors recurred. Three (43%) of the seven subtotally resected tumors grew during the follow-up interval. Vision improved in 11 (61%) of 18 cases and worsened in three (17%) as a result of surgery. New instances of postoperative endocrinopathy occurred as follows: hypogonadism (one of six cases), GH deficiency (four of seven cases), hypothyroidism (11 of 14 cases), hypocortisolemia (eight of 15 cases), and DI (nine of 16 cases). No instance of preoperative endocrinopathy was corrected through TC surgery. Four patients (22%) exhibited short-term memory loss and 11 (61%) had hyperphagia after surgery. When compared with those in the TC group, patients in the TN group had shorter hospital stays.

Conclusions. Use of the TN approach can render good outcomes in properly selected patients with craniopharyngioma, particularly when the tumor is cystic. Even in mostly suprasellar cases, an extended TN approach can afford complete resection. Note that endocrine function often worsens after surgery and that postoperative obesity can be a significant problem.
Combined cimetidine and temozolomide, compared with temozolomide alone: significant increases in survival in nude mice bearing U373 human glioblastoma multiforme orthotopic xenografts
Authors: Lefranc Florence , James Syril , Camby Isabelle , Gaussin Jean-François , Darro Francis , Brotchi Jacques , Gabius Joachim , Kiss Robert
Published: May 2009

Object. Malignant gliomas consist of both heterogeneous proliferating and migrating cell subpopulations, with migrating glioma cells exhibiting less sensitivity to antiproliferative or proapoptotic drugs than proliferative cells. Therefore, the authors combined cimetidine, an antiinflammatory agent already proven to act against migrating epithelial cancer cells, with temozolomide to determine whether the combination induces antitumor activities in experimental orthotopic human gliomas compared with the effects of temozolomide alone.

Methods. Cimetidine added to temozolomide compared with temozolomide alone induced survival benefits in nude mice with U373 human glioblastoma multiforme (GBM) cells orthotopically xenografted in the brain. Computer-assisted phase-contrast microscopy analyses of 9L rat and U373 human GBM cells showed that cimetidine significantly decreased the migration levels of these tumor cells in vitro at concentrations at which tumor growth levels were not modified (as revealed on monotetrazolium colorimetric assay). Computer-assisted microscope analyses of neoglycoconjugate-based glycohistochemical staining profiles of 9L gliosarcomas grown in vivo revealed that cimetidine significantly decreased expression levels of endogenous receptors for fucose and, to a lesser extent, for N-acetyl-lactosamine moieties. Endogenous receptors of this specificity are known to play important roles in adhesion and migration processes of brain tumor cells.

Conclusions. Cimetidine, acting as an antiadhesive and therefore an antimigratory agent for glioma cells, could be added in complement to the cytotoxic temozolomide compound to combat both migrating and proliferating cells in GBM.
Dexamethasone preventing contractile and cytoskeletal protein changes in the rabbit basilar artery after subarachnoid hemorrhage
Authors: Gomis Philippe , Tran-Dinh Yves Roger , Sercombe Christine , Sercombe Richard
Published: May 2009

Object. The aim of this project was to study the perturbations of four smooth-muscle proteins and an extracellular protein, type I collagen, after subarachnoid hemorrhage (SAH) and to examine the possible preventive effects of dexamethasone.

Methods. Using a one-hemorrhage rabbit model, the authors first examined the effects of SAH on the expression of α-actin, h-caldesmon, vimentin, smoothelin-B, and type I collagen; second, they studied whether post-SAH systemic administration of dexamethasone (three daily injections) corrected the induced alterations. Measurements were obtained at Day 7 post-SAH. The proteins were studied by performing immunohistochemical staining and using a laserscanning confocal microscope.

Compared with control (sham-injured) arteries, the density of the media of arteries subjected to SAH was reduced for α-actin (−11%, p = 0.01) and h-caldesmon (−15%, p = 0.06) but increased for vimentin (+15%, p = 0.04) and smoothelin-B (+53%, p = 0.04). Among animals in which SAH was induced, arteries in those treated with dexamethasone demonstrated higher values of density for α-actin (+13%, p = 0.05) and h-caldesmon (+20%, p = 0.01), lower values for vimentin (−55%, p = 0.05), and nonsignificantly different values for smoothelin-B. The density of type I collagen in the adventitia decreased significantly after SAH (−45%, p = 0.01), but dexamethasone treatment had no effect on this decrease.

Conclusions. The SAH-induced alterations in the density of three of four smooth-muscle proteins were prevented by dexamethasone treatment; two of these proteins—α-actin and h-caldesmon—are directly related to contraction. This drug may potentially be useful to prevent certain morphological and functional changes in cerebral arteries after SAH.
Long-term high-frequency bilateral pallidal stimulation for neuroleptic-induced tardive dystonia
Authors: Franzini Angelo , Marras Carlo , Ferroli Paolo , Zorzi Giovanna , Bugiani Orso , Romito Luigi , Broggi Giovanni
Published: May 2009

✓ The authors report the results of long-term bilateral high-frequency pallidal stimulation in two patients affected by neuroleptic-induced dystonia.

The first patient, a 33-year-old man, experienced a dystonic posture of the trunk, with involvement of the neck and upper and lower limbs after 11 years of treatment with neuroleptic drugs. The second patient, a 30-year-old man, presented with a torsion dystonia, spasmodic torticollis, and involuntary movements of the upper limbs, which appeared after 4 years of neuroleptic treatment. Both of these dystonias worsened even after the neuroleptic treatment had been discontinued, and neither patient responded to clozapine or benzodiazepine therapy. The time lapse between the first appearance of dystonia and surgery was, respectively, 5 and 3 years. In each case bilateral stereotactic implantation of electrodes within the globus pallidus internus (GPI) was performed while the patient was in a state of general anesthesia. The electrodes were placed at the following anterior commissure—posterior commissure line—related coordinates: 20 mm lateral to the midline, 6 mm below the intercommissural plane, and 3 mm anterior to the midcommissural point. Electrical stimulation (130 Hz, 1 V, 90 µsec) was begun on the 1st postoperative day. In both patients, a genetic analysis positively ruled out a mutation in the DYT1 gene, and magnetic resonance imaging yielded normal findings in both cases.

Extrapyramidal symptoms and dystonia disappeared almost completely and dramatically in both patients just a few days after high-frequency bilateral pallidal stimulation commenced. Both patients regained autonomy and neuroleptic treatment was reinitiated. The follow-up period for both cases was 1 year. Long-term bilateral high-frequency stimulation of GPI resulted in a dramatic and long-lasting improvement of neuroleptic-induced tardive dystonia.
De novo presentation of an arteriovenous malformation
Authors: Gonzalez L. Fernando , Bristol Ruth E. , Porter Randall W. , Spetzler Robert F.
Published: May 2009

✓ The authors report the case of a patient with a de novo arteriovenous malformation (AVM), indicating that the origin of these lesions may not always be congenital.

A 3-year-old girl who was struck by a car suffered a mild head injury and experienced posttraumatic epilepsy. The initial magnetic resonance (MR) image obtained in this child revealed only a small contusion in the left frontal lobe. Intractable epilepsy subsequently developed. A second MR image obtained almost 4 years after the injury demonstrated an AVM in the right posterior temporal lobe that was verified using angiography. The lesion was classified as a Spetzler—Martin Grade III AVM. The patient underwent embolization of the feeding vessels followed by gamma knife surgery. Fourteen months after treatment she was asymptomatic. Follow-up MR images demonstrate no evidence of an AVM and no changes in the white matter.

This case presents a de novo AVM that developed within approximately 4 years. The findings indicate that AVMs may not always be congenital and reinforce the concept that the natural history of AVMs is dynamic. Lesions may appear de novo, grow, and thrombose spontaneously.
Intracranial metastasis from a sacrococcygeal chordoma
Authors: Kamel Mahmoud Hamdy , Lim Chris , Kelleher Michael , Aquilina Kristian , Keohane Catherine , Kaar George
Published: May 2009

✓ Chordoma is a locally invasive tumor of low metastatic potential. Only six cases of chordoma that metastasized to the brain are found in the English literature. Most of these lesions were clinically silent and all were associated with extraneural metastases. The authors report a case of symptomatic brain metastasis from a sacrococcygeal chordoma in the absence of other metastases. The incidence, sites, and factors predictive of chordoma metastasis are discussed.
Battling blood loss in neurosurgery: Harvey Cushing's embrace of electrosurgery
Authors: Voorhees Jennifer R. , Cohen-Gadol Aaron A. , Laws Edward R. , Spencer Dennis D.
Published: May 2009

✓ For his pioneering spirit, definitive work, and unparalleled devotion to conquering neurosurgery's toughest obstacles, Harvey Williams Cushing inarguably has earned the title, “The Father of Neurosurgery.” His revolutionary incorporation of electrosurgical techniques in neurosurgery was not exceptional, but part of a pattern of recognizing, embracing, and establishing the use of medical technologies with great potential. Until 1910, Cushing had systematically reduced neurosurgery's primary complications—infection and the effects of intracranial pressure—to decrease mortality rates. Hemostasis had always been a concern of William Halsted's surgical protégé, but only after 1910 could Cushing primarily focus on it. In fact, Cushing's crucial collaboration with William T. Bovie and his electrosurgical apparatus conquered this major obstacle in 1926. The nature of their collaboration—two experts in their respective fields who were passionate about their work, working side by side in the operating room—resulted in progress that surpassed all predecessors in the field. Cushing never did learn the physics behind one of the most important advances of his career. Nonetheless, he did know that by greatly reducing blood loss, electrosurgery allowed him to operate in patients whose tumors had been previously deemed inoperable and on the entire spectrum of neurosurgical patients more safely.
Program self-evaluation: the evolution of an injury prevention foundation
Authors: Rosenberg Rachel I. , Zirkle Dorothy L. , Neuwelt Edward A.
Published: May 2009

Object. Injuries are a leading cause of morbidity and mortality in the US. The authors provide a brief discussion of a national injury prevention foundation's self-evaluation of its efforts to decrease the incidence of traumatic injuries through educational programs, legislative efforts, and community programming.

Methods. The authors performed a literature review of evaluation studies and activities of the Think First National Injury Prevention Foundation accomplished between 1986 and 2002 and summarized their findings.

Suggestions generated from research studies were incorporated into the foundation's programs. Efficacy studies show that the injury prevention programs have a significant impact on knowledge, attitudes, and practice, and demonstrate the need for injury prevention to be recognized as a valuable component of the US medical system.

Conclusions. After a self-evaluation, the Think First National Injury Prevention Foundation has made strides in developing a multilevel approach to injury prevention by combining education with legislative initiatives, community-wide safety programming, and a large public presence, similar to what has been accomplished with successful smoking cessation programs and seat-belt use campaigns.
Posttraumatic migraine characteristics in athletes following sports-related concussion
Authors: Mihalik Jason P. , Stump Jamie E. , Collins Michael W. , Lovell Mark R. , Field Melvin , Maroon Joseph C.
Published: May 2009

Object. The object of this study was to compare symptom status and neurocognitive functioning in athletes with no headache (non-HA group), athletes complaining of headache (HA group), and athletes with characteristics of posttraumatic migraine (PTM group).

Methods. Neurocognitive tests were undertaken by 261 high-school and collegiate athletes with a mean age of 16.36 ± 2.6 years. Athletes were separated into three groups: the PTM group (74 athletes with a mean age of 16.39 ± 3.06 years), the HA group (124 athletes with a mean age of 16.44 ± 2.51 years), and the non-HA group (63 patients with a mean age of 16.14 ± 2.18 years). Neurocognitive summary scores (outcome measures) for verbal and visual memory, visual motor speed, reaction time, and total symptom scores were collected using ImPACT, a computer software program designed to assess sports-related concussion.

Significant differences existed among the three groups for all outcome measures. The PTM group demonstrated significantly greater neurocognitive deficits when compared with the HA and non-HA groups. The PTM group also exhibited the greatest amount of departure from baseline scores.

Conclusions. The differences among these groups can be used as a basis to argue that PTM characteristics triggered by sports-related concussion are related to increased neurocognitive dysfunction following mild traumatic brain injury. Thus, athletes suffering a concussion accompanied by PTM should be examined in a setting that includes symptom status and neurocognitive testing to address their recovery more fully. Given the increased impairments observed in the PTM group, in this population clinicians should exercise increased caution in decisions about treatment and when the athlete should be allowed to return to play.
Blood pressure in the artery distal to an intraarterial embolus during thrombolytic therapy for occlusion of a major artery: a predictor of cerebral infarction following good recanalization
Authors: Sorimachi Takatoshi , Fujii Yukihiko , Tsuchiya Naoto , Nashimoto Takeo , Saito Masatsune , Morita Kenichi , Ito Yasushi , Tanaka Ryuichi
Published: May 2009

Object. The aim in this study was the investigation of back pressure in arteries distal to the occlusion site during intraarterial thrombolysis as well as the usefulness of back pressure measurement in combination with diffusion-weighted (DW) magnetic resonance (MR) imaging to predict the occurrence of ischemic lesions following good recanalization.

Methods. Twenty-five consecutive patients with severe hemiparesis caused by embolism of the internal carotid artery (10 patients) and the proximal middle cerebral artery (15 patients) were treated using intraarterial thrombolysis. Systolic back pressure, measured through a microcatheter in the artery just distal to the emboli, ranged from 22 to 78 mm Hg. According to an angiographic inclusion criterion for good recanalization—that is, recanalization of the M2 or more distal arteries at the end of thrombolysis—21 of 25 patients underwent evaluation in this study. In 14 patients volumes of low-density areas on computerized tomography (CT) scans obtained 2 months postthrombolysis were smaller in comparison with volumes of hyperintense areas on DW MR images acquired before treatment, whereas these low-density areas were larger in seven patients. Compared with those on initial DW MR images, the volume of abnormalities on CT scans obtained 2 months posttreatment were significantly reduced in patients with a systolic back pressure greater than 30 mm Hg (16 patients) than in those with a back pressure of 30 mm Hg or less (five patients) (p < 0.05). Systolic back pressures greater than 30 mm Hg were associated with significantly better modified Rankin Scale scores than those 30 mm Hg or less (p < 0.05).

Conclusions. Back pressure measurement in combination with DW MR imaging can be used to predict the occurrence of infarction as demonstrated on CT scans following thrombolysis.
Decrease in platelet count as an independent risk factor for symptomatic vasospasm following aneurysmal subarachnoid hemorrhage
Authors: Hirashima Yutaka , Hamada Hideo , Kurimoto Masanori , Origasa Hideki , Endo Shunro
Published: May 2009

Object. Increased platelet consumption is expected in patients with cerebral vasospasm, according to data from clinical and experimental studies. The authors investigated sequential changes in platelet counts in patients with subarachnoid hemorrhage (SAH) and the difference in platelet consumption between patients with and those without symptomatic vasospasm (SV). Variables related to platelet count as well as other clinical and radiological variables were analyzed as independent predictors of SV.

Methods. One hundred consecutive patients who had undergone surgery within 48 hours after SAH onset were entered in the study. Clinical and radiological variables and blood cell counts, including red blood cells, white blood cells, and platelets, after SAH were retrospectively examined. Twenty of these variables were entered into univariate and multivariate analyses to determine predictors for SV.

After SAH, the platelet count decreased to a minimum and then increased rapidly to levels greater than those recorded on admission. This change was specific to SAH, and platelet consumption was more severe in patients with SV than in those without. There were three independent predictors of SV: a ratio of the lowest platelet count and the admission count greater than 0.7 (odds ratio [OR] 0.322, 95% confidence interval [CI] 0.124–0.834, p = 0.0196) and a history of hypertension (OR 0.338, 95% CI 0.126–0.906, p = 0.0311) were negatively significant (that is, decreases the occurrence of SV), and a Fisher Grade 3 (OR 4.42, 95% CI 1.48–13.2, p = 0.0077) was positively significant (that is, increases the occurrence of SV).

Conclusions. The association between a decrease in platelet count and the occurrence of SV indicates the important role of platelets in the pathophysiology of vasospasm following SAH.
Incidence of hemorrhage associated with electrophysiological studies performed using macroelectrodes and microelectrodes in functional neurosurgery
Authors: Gorgulho Alessandra , De Salles Antonio A. F. , Frighetto Leonardo , Behnke Eric
Published: May 2009

Object. The goal of this study was to analyze the incidence of intracranial bleeding in patients who underwent procedures guided by microelectrode recording (MER) rather than by macroelectrode stimulation alone.

Methods. Between March 1994 and July 2001, 178 patients underwent 248 functional neurosurgical procedures performed by the same team at the University of California at Los Angeles. The procedures included pallidotomy (122 patients), thalamotomy (19 patients), and implantation of deep brain stimulation electrodes in the subthalamic nucleus (36 patients), globus pallidus internus (17 patients), and ventralis intermedius nucleus (54 patients). One hundred forty-four procedures involved macroelectrode stimulation and 104 involved MER. Groups were analyzed according to the presence of arterial hypertension, MER or macroelectrode stimulation use, and occurrence of hemorrhage. Nineteen patients with arterial hypertension underwent 28 surgical procedures.

Five cases of hemorrhage (2.02%) occurred. One patient presented with hemiparesis and dysphasia but no surgery was required. The incidence of hemorrhage in patients in whom MER was performed was 2.9%, whereas the incidence in patients in whom MER was not used was 1.4% (p = 0.6529). Bleeding occurred in 10.71% of patients with hypertension and 0.91% of those who were nonhypertensive (p = 0.0111). Among the 104 patients in whom MER was performed, 12 had hypertension. Bleeding occurred in two (16.67%) of these 12 patients. An increased incidence of bleeding in hypertensive patients who underwent MER (p = 0.034) was noticed when compared with nonhypertensive patients who underwent MER. A higher number of electrode passes through the parenchyma was observed when MER was used (p = 0.0001). A positive trend between the occurrence of hemorrhage and multiple passes was noticed.

Conclusions. Based on the data the authors suggest that a higher incidence of hemorrhage occurs in hypertensive patients, and a higher incidence as well in hypertensive patients who underwent MER rather than macroeletrode stimulation. Special attention should be given to MER use in hypertensive patients and particular attention should be made to multiple passes.
Surgical anatomy of the axillary nerve within the quadrangular space
Authors: Tubbs R. Shane , Tyler-Kabara Elizabeth C. , Aikens Alan C. , Martin Justin P. , Weed Leslie L. , Salter E. George , Oakes W. Jerry
Published: May 2009

Object. There is a paucity of literature regarding the surgical anatomy of the quadrangular space (QS), which is a potential site of entrapment for the axillary nerve. Muscle hypertrophy of this geometrical area and fascial bands within it have been implicated in compression of the axillary nerve.

Methods. Fifteen human cadavers (30 sides) were dissected for this study. Measurements of the QS and its contents were made. The mean height of this space was 2.5 cm and the mean width 2.5 cm; its mean depth was 1.5 cm. The axillary nerve was always the most superior structure in the space, and in all cases the nerve and artery hugged the surgical neck of the humerus just superior to the origin of the lateral head of the triceps brachii muscle. This arrangement placed the axillary nerve in the upper lateral portion of the QS in all cadaveric specimens. The nerve branched into its muscular components within this space in 10 sides (33%) and posterior to it in 20 sides (66%). The cutaneous component of the axillary nerve branched from the main trunk of the nerve posterior to the QS in all specimens. Fascial bands were found in this space in 27 (90%) of 30 sides.

Conclusions. Knowledge of the anatomy of the QS may aid the surgeon who wishes to explore and decompress the axillary nerve within this geometrical confine.
Intraoperative perfusion computerized tomography scanning for management of intracranial stent placement in a patient with tandem intracranial stenoses
Authors: Sanford Matthew F. , Turk Aquilla S. , Niemann David B. , Pulfer Kari A. , Aagaard-Kienitz Beverly A.
Published: May 2009

✓ The authors describe the novel use of cerebral perfusion computerized tomography studies to evaluate the effectiveness of internal carotid artery stent placement in a man with symptomatic transient ischemic attacks caused by tandem stenoses of the internal carotid and middle cerebral arteries.
Intracranial endovascular stent placement for symptomatic metastatic non-Hodgkin lymphoma
Authors: Rajpal Sharad , Niemann David B. , Aagaard-Kienitz Beverly , Turk Aquilla S.
Published: May 2009

✓ A case of cranial-based metastatic non-Hodgkin lymphoma with cerebral vascular compromise is presented. The patient underwent intracranial endovascular stent placement resulting in an improvement in his symptoms. This is the first reported case of endovascular stent placement for an intracranial neoplasm in the literature to date.
Long-term resolution of acute, obstructive, triventricular hydrocephalus by endoscopic removal of a third ventricular hematoma without third ventriculostomy
Authors: Barbagallo Giuseppe M. V. , Platania Nunzio , Schonauer Claudio
Published: May 2009

✓ The authors describe a new extension of the use of neuroendoscopy beyond that which is ordinarily performed. The authors report on the resolution of acute, obstructive, triventricular hydrocephalus in a 42-year-old woman with hypertensive caudate hemorrhage that migrated into the ventricular system. The patient underwent emergency endoscopic removal of a third ventricular hematoma, which was obstructing the orifice of the aqueduct, and restoration of cerebrospinal fluid (CSF) flow but no third ventriculostomy. The authors believe that this is the first such case to be reported. In selected cases of third ventricular hemorrhage, endoscopic removal of the intraventricular hematoma may represent a useful and effective treatment option even in emergency conditions as well as a better alternative to prolonged CSF external ventricular drainage. A reduction in the duration of hospitalization is a beneficial consequence. The authors assert that third ventriculostomy is not always needed.
Vagus nerve stimulation for chronic intractable hiccups
Authors: Payne Bryan Rankin , Tiel Robert Lyons , Payne Mary Say , Fisch Bruce
Published: May 2009

✓ Intractable hiccups are debilitating and usually a result of some underlying disease. Initial management includes vagal maneuvers and pharmacotherapy. When hiccups persist despite medical therapy, surgical intervention rarely is pursued. Cases described in the literature cite successful phrenic nerve blockade, crush injury, or percutaneous phrenic nerve pacing. The authors report on a case of intractable hiccups occurring after a posterior fossa stroke. Complete resolution of the spasms has been achieved to date following the placement of a vagus nerve stimulator.