bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-dose Trigeminal Neuralgia Radiosurgery Associated with Increased Risk of Trigeminal Nerve Dysfunction
Authors: Pollock Bruce E. , Phuong Loi K. , Foote Robert L. , Stafford Scott L. , Gorman Deborah A. 
Published: July 2004

Abstract

OBJECTIVE
Stereotactic radiosurgery is being used with more frequency in the management of patients with trigeminal neuralgia. To improve facial pain outcomes, many centers have increased the prescribed radiation dose to the trigeminal nerve.

METHODS
Between April 1997 and December 1999, 68 patients underwent radiosurgery for trigeminal neuralgia with use of the Leksell gamma knife (Elekta Instruments, Norcross, GA) and a single 4-mm isocenter of radiation. Twenty-seven patients (40%) received 70 Gy (low dose) of irradiation and 41 patients (60%) received 90 Gy (high dose). The groups were similar with regard to age, sex, duration of pain, number of prior surgeries, and preexisting trigeminal deficits. The primary facial pain outcomes for analysis were excellent (pain-free, no medications) and good (pain-free, reduced medications). The mean length of follow-up after radiosurgery was 14.4 months (range, 2–36 mo).

RESULTS
At last follow-up examination, 11 (41%) of the 27 patients with low-dose radiosurgery remained pain-free compared with 25 (61%) of the 41 patients with high-dose radiosurgery (P = 0.17). Additional surgery was performed in 12 low-dose patients (44%) and 8 high-dose patients (20%) (P = 0.05). High-dose radiosurgery was associated with an increased rate of permanent trigeminal nerve dysfunction (54% versus 15%, P = 0.003). Bothersome dysesthesias occurred in 13 high-dose patients (32%), whereas only 1 low-dose patient had this complication (P = 0.01). Three high-dose patients (8%) developed corneal numbness after radiosurgery. Pain recurred with more frequency in patients not developing trigeminal nerve dysfunction after radiosurgery (9 of 22 patients, 41%) compared with those who sustained facial numbness, paresthesias, or dysesthesias (4 of 27 patients, 15%); however, the difference was not statistically significant (P = 0.08).

CONCLUSION
Higher doses of radiation may correlate with better facial pain outcomes after radiosurgery for trigeminal neuralgia. However, the incidence of significant trigeminal nerve dysfunction is markedly increased after radiosurgery for patients receiving high-dose radiosurgery. Because of the nonselective nature of this ablative technique, dose prescription should be limited to less than 90 Gy.
C1–C2 Transarticular Screw Fixation for Atlantoaxial Instability: A 6-year Experience
Authors: Haid Regis W. , Subach Brian R. , McLaughlin Mark R. , Rodts Gerald E. , Wahlig John B. 
Published: July 2004

Abstract

OBJECTIVE
We review a 6-year, single-center experience using the technique of C1–C2 transarticular screw fixation for atlantoaxial instability in 75 consecutive operations.

METHODS
The study group was composed of 43 men and 32 women, with a mean age of 44 years (range, 8–76 yr). Each patient had documented atlantoaxial instability. In 28 patients (37%), atlantoaxial instability was a result of trauma; in 22 patients, (29%), it was a result of rheumatoid arthritis; in 16 patients (21%), it was a result of prior surgery; and in 9 patients (12%), it was a result of congenital abnormalities. All patients underwent stabilization with C1–C2 transfacetal screws and a posterior interspinous construct. Nine patients had unilateral screws placed. Postoperatively, the patients were maintained in a rigid cervical orthosis for a mean of 11 weeks (range, 8–15 wk); five patients were immobilized with halo fixation for a mean of 13 weeks (range, 10–16 wk). The mean follow-up period was 2.4 years (range, 1–5.5 yr).

RESULTS
Osseous fusion was documented in 72 patients (96%). There were no hardware failures; however, three patients developed pseudarthrosis. Two superficial wound infections (one at the graft site and one at the cervical incision site) required antibiotic therapy. Four patients had transient suboccipital hypesthesia. No instances of an errant screw, dural laceration, or injury to the vertebral artery, spinal cord, or hypoglossal nerve were noted.

CONCLUSION
C1–C2 transarticular screw fixation supplemented with an interspinous construct yielded a 96% fusion rate, with a low incidence of complications. We attribute our successful outcomes to careful preoperative assessment and meticulous surgical technique.
Three-dimensional Visualization of the Pyramidal Tract in a Neuronavigation System during Brain Tumor Surgery: First Experiences and Technical Note
Authors: Coenen Volker A. , Krings Timo , Mayfrank Lothar , Polin Richard S. , Reinges Marcus H.T. , Thron Armin , Gilsbach Joachim M. 
Published: July 2004

Abstract

OBJECTIVE
To integrate spatial three-dimensional information concerning the pyramidal tracts into a customized system for frameless neuronavigation during brain tumor surgery.

METHODS
Four consecutive patients with intracranial tumors in eloquent areas underwent diffusion-weighted and anatomic magnetic resonance imaging studies within 48 hours before surgery. Diffusion-weighted datasets were merged with anatomic data for navigation purposes. The pyramidal tracts were segmented and reconstructed for three-dimensional visualization. The reconstruction results, together with the fused-image dataset, were available during surgery in the environment of a customized neuronavigation system.

RESULTS
In all four patients, the combination of reconstructed data and fused images was a helpful additional source of information concerning the tumor seat and topographical interaction with the pyramidal tract. In two patients, intraoperative motor cortex stimulation verified the tumor seat with regard to the precentral gyrus.

CONCLUSION
Diffusion-weighted magnetic resonance imaging allows individual estimation of large fiber tracts applicable as important information in intraoperative neuronavigation and in planning brain tumor resection. A three-dimensional representation of fibers associated with the pyramidal tract during brain tumor surgery is feasible with the presented technique and is a helpful adjunct for the neurosurgeon. The main drawbacks include the length of time required for the segmentation procedure, the lack of direct intraoperative control of the pyramidal tract position, and brain shift. However, mapping of large fiber tracts and its intraoperative use for neuronavigation have the potential to increase the safety of neurosurgical procedures and to reduce surgical morbidity.
Transsphenoidal Approaches for the Extracapsular Resection of Midline Suprasellar and Anterior Cranial Base Lesions
Authors: Kaptain George J. , Vincent David A. , Sheehan Jason P. , Laws Edward R. 
Published: July 2004

Abstract

OBJECTIVE
The transsphenoidal approach is an effective method for treating tumors contained within the sella or extending into the suprasellar cistern. The technique of tumor dissection is predicated on preservation of the integrity of the diaphragma, i.e., intracapsular removal. Gross total extracapsular dissection may, however, be accomplished either by using a standard approach to the pituitary fossa or by extending the exposure to include removal of a portion of the planum sphenoidale and division of the superior intercavernous sinus.

METHODS
Included in this series were 14 patients with parasellar or sellar tumors with extension into the anterior fossa and/or suprasellar cistern. For 4 of 14 patients (29%), extracapsular access was gained by broaching the tumor capsule from within the pituitary fossa. For the remaining 10 of 14 patients (71%), the dura of the floor of the sella and the planum sphenoidale was exposed, using neuronavigation to verify the limits of bony dissection; extracapsular tumor resection was performed using the operating microscope and endoscopy as indicated. The dural defect was repaired with abdominal fat, the sellar floor and planum sphenoidale were reconstructed, and in selected cases a lumbar drain was placed.

RESULTS
Seven of 14 tumors (50%) were craniopharyngiomas, 3 of 14 (21%) were pituitary adenomas, and 2 of 14 (14%) were meningiomas. There was one case of lymphocytic hypophysitis and one yolk sac tumor. Gross total resection was possible in 11 of 14 cases (79%). Immediate postoperative visual function worsened in 2 of 14 cases (14%), improved in 3 of 14 cases (21%), and was stable in the remainder of cases. Postoperatively, 2 of 14 patients (14%) developed bacterial meningitis. Overt postoperative cerebrospinal fluid rhinorrhea was not observed.

CONCLUSION
Gross total extracapsular resection of midline suprasellar tumors via a transsphenoidal approach is possible but is associated with a higher risk of complications than is standard transsphenoidal surgery.
Surgery on Anterior Foramen Magnum Meningiomas Using a Conventional Posterior Suboccipital Approach: A Report on an Experience with 17 Cases
Authors: Goel Atul , Desai Ketan , Muzumdar Dattatraya 
Published: July 2004

Abstract

OBJECTIVE
The advantages of a posterior “conventional” suboccipital approach with a midline incision over lateral, anterolateral, and anterior approaches to anteriorly placed foramen magnum meningiomas are discussed.

METHODS
From 1991 to March 2000, 17 patients with foramen magnum meningiomas arising from the anterior or anterolateral rim of the foramen magnum underwent operations in the Department of Neurosurgery at King Edward Memorial Hospital and Seth G.S. Medical College. All patients were operated on in a semi-sitting position by use of a conventional suboccipital approach with a midline incision and extension of the craniectomy laterally toward the side of the tumor up to the occipital condyle.

RESULTS
The patients ranged in age from 17 to 72 years, and the tumors ranged in size from 2.1 to 3.8 cm. The intradural vertebral artery was at least partially encased on one side in eight patients and on both sides in two patients. The brainstem was displaced predominantly posteriorly in each patient. A partial condylar resection was performed in two cases to enhance the exposure. Total tumor resection was achieved in 14 patients, and a subtotal resection of the tumor was performed in the other 3 patients. In one patient, a small part of the tumor was missed inadvertently, and in the other two patients, part of the tumor in relation to the vertebral artery and posterior inferior cerebellar artery was deliberately left behind. After surgery, one patient developed exaggerated lower cranial nerve weakness. There was no significant postoperative complication in the remainder of the patients, and their conditions improved after surgery. The average length of follow-up is 43 months, and there has been no recurrence of the tumor or growth of the residual tumor.

CONCLUSION
From our experience, we conclude that a large majority of anterior foramen magnum meningiomas can be excised with a lateral suboccipital approach and meticulous microsurgical techniques.
Adjunctive Use of Endoscopy during Posterior Fossa Surgery to Treat Cranial Neuropathies
Authors: King Wesley A. , Wackym Phillip A. , Sen Chandranath , Meyer Glenn A. , Shiau John , Deutsch Harel 
Published: July 2004

AbstractOBJECTIVEThe objective of this study was to determine the utility and safety of rigid endoscopy as an adjunct during posterior fossa surgery to treat cranial neuropathies.METHODSA suboccipital craniotomy was performed for 19 patients with non-neoplastic processes involving the Vth, VIIth, and/or VIIIth cranial nerves. Ten patients with trigeminal neuralgia (n = 8), hemifacial spasm (n = 1), or intractable tinnitus (n = 1) underwent primarily microvascular decompression procedures. One patient with geniculate neuralgia underwent nervus intermedius sectioning combined with microvascular decompression. Eight patients underwent unilateral vestibular nerve neurectomies for treatment of Ménière's disease. A 0- or 30-degree rigid endoscope was used in conjunction with the standard microscopic approach for all procedures.RESULTSAll patients experienced resolution or significant improvement of their preoperative symptoms after posterior fossa surgery. The endoscope allowed improved definition of anatomic neurovascular relationships without the need for significant cerebellar or brainstem retraction. Cleavage planes between the cochlear and vestibular nerves entering the internal auditory canal and sites of vascular compression could not be microscopically observed for several patients; however, endoscopic identification was possible for all patients. There were no complications related to the use of the endoscope.CONCLUSIONThe rigid endoscope can be used safely during posterior fossa surgery to treat cranial neuropathies, and it allows improved observation of the cranial nerves, nerve cleavage planes, and vascular anatomic features without significant cerebellar or brainstem retraction.
Evidence of Increased Endothelial Cell Turnover in Brain Arteriovenous Malformations
Authors: Hashimoto Tomoki , Mesa-Tejada Ricardo , Quick Christopher M. , Bollen Andrew W. , Joshi Shailendra , Pile-Spellman John , Lawton Michael T. , Young William L. 
Published: July 2004

AbstractOBJECTIVEWe hypothesized that human brain arteriovenous malformations (BAVMs) are nonstatic vascular lesions with active angiogenesis or vascular remodeling. To test this hypothesis, we assessed endothelial cell turnover in BAVMs.METHODSWe identified nonresting endothelial cells by use of immunohistochemistry for the Ki-67 antigen. From archived paraffin blocks, we selected BAVM vessels without intravascular thrombosis or embolic material in areas nonadjacent to the nidus edge. For controls, we used 50- to 100-μm diameter cortical vessels from temporal lobe cortex removed for epilepsy treatment. The Ki-67 index was calculated as a percentage of Ki-67-positive endothelial cells. The data were analyzed by the nonparametric Mann-Whitney test and reported as mean ± standard deviation.RESULTSThirty-seven specimens that met the above criteria were selected. There were 26 ± 15 vessels counted in each BAVM specimen versus 18 ± 5 in each control cortex (n = 5). The mean Ki-67 index was higher for BAVM vessels than control cortical vessels (0.7 ± 0.6 versus 0.1 ± 0.2%;P = 0.005), which represented an approximately seven-fold increase in the number of nonresting endothelial cells. In the BAVM group, there was a trend for younger patients to have a wider variation and higher Ki-67 index than older patients; no trend was evident in the control group.CONCLUSIONCompared with control vessels, BAVM vessels have higher endothelial cell turnover, which suggests the presence of active angiogenesis or vascular remodeling in BAVMs.
Multiple Intracranial Aneurysms as Delayed Complications of an Atrial Myxoma: Case Report
Authors: Jean Walter C. , Walski-Easton Sabrina M. , Nussbaum Eric S. 
Published: July 2004

Abstract

OBJECTIVE AND IMPORTANCE
Atrial myxomas are rare cardiac tumors that may cause neurological complications; however, delayed neurological events after total tumor resection are rare. In this report, we present a patient who developed transient cerebral ischemic attacks and was found to have multiple intracranial aneurysms 5 years after successful resection of her atrial myxoma. At the time of myxoma resection, there were no neurological symptoms; at the time of presentation with transient ischemic attacks, there was no evidence of atrial recurrence.

CLINICAL PRESENTATION
A 32-year-old woman presented with five episodes of right arm and face paresthesia, each lasting 15 to 20 minutes, 5 years after successful resection of her atrial myxoma. Clopidogrel bisulfate therapy was initiated, with resolution of her symptoms. Angiography revealed multiple, peripherally located, fusiform cerebral aneurysms.

INTERVENTION
A left frontal craniotomy for resection and biopsy of one of the aneurysms was performed, to establish the diagnosis. Pathological analysis of the biopsied aneurysm provided evidence of direct atrial myxoma invasion and occlusion of the cerebral blood vessel.

CONCLUSION
Neurological symptoms may accompany or lead to the diagnosis of atrial myxoma. Rarely, as in this case, myxomatous aneurysms may develop years after definitive treatment of the primary tumor. Patients who have undergone successful resection of a left atrial myxoma may be at risk for delayed cerebral ischemia associated with aneurysm development, and this phenomenon must be considered for patients with neurological symptoms who present even years after myxoma removal. The natural history, pathophysiological features, and treatment dilemma of these aneurysms are discussed.
Arachnoid Cyst of the Craniocervical Junction: Case Report
Authors: Price Stephen J. , David Karoly M. , O'Donovan Dominic G. , Aspoas A. Robert 
Published: July 2004

Abstract

OBJECTIVE AND IMPORTANCE
An arachnoid cyst at the craniocervical junction presenting with obstructive hydrocephalus as a result of blockage of the outflow of the fourth ventricle is described. This is a very rare anatomic site, with only five other cases described in the literature.

CLINICAL PRESENTATION
A 37-year-old woman presented with a 9-month history of severe neck pain, persistent vomiting, visual disturbances, and numbness of the nose, cheek, and lips. She had severe bilateral papilledema on ophthalmoscopy. Magnetic resonance imaging revealed a midline cystic lesion extending down to C2.

INTERVENTION
The patient underwent posterior fossa craniectomy and excision of the arachnoid cyst. She made a full recovery and was asymptomatic at follow-up examination.

CONCLUSION
The symptomatology of these rare craniocervical arachnoid cysts and their development are discussed.
Adrenocorticotropic Hormone-producing Pituitary Tumors: 12- to 22-year Follow-up after Treatment with Stereotactic Radiosurgery
Authors: Höybye Charlotte , Grenbäck Eva , Rähn Tiit , Degerblad Marie , Thorén Marja , Hulting Anna-Lena 
Published: July 2004

Abstract

OBJECTIVE
To study retrospectively long-term outcomes of patients with adrenocorticotropic hormone-producing pituitary tumors that were treated with stereotactic Leksell gamma knife unit radiosurgery.

METHODS
Eighty-nine patients aged 5 to 67 years were treated between 1976 and 1985. Eighteen patients aged 18 to 68 years (mean age, 41 yr) were followed in detail. Fifteen patients were women. None had previously received conventional radiotherapy, but pituitary microsurgery had been performed in two patients, and one patient had had an adrenalectomy. In the remaining 15 patients, radiosurgery was the primary therapy.

RESULTS
Sixty-four patients had one stereotactic treatment, and 25 patients had two or more treatments. No complications were observed during treatment and the immediate follow-up period. At follow-up, 17 patients had died 1 to 20 years after the first treatment. No deaths were related to the treatment. In our 18 patients, the follow-up time after the first radiosurgical treatment was 12 to 22 years (mean follow-up period, 17 yr). Urinary cortisol levels gradually normalized in 83% of the patients. No recurrences were observed. Pituitary hormone insufficiencies developed in about two of every three patients and occurred even more than 10 years after treatment. Eight patients had transient hyperprolactinemia. The patients' vision and visual fields were unaffected, and none of them had signs of radiation-induced side effects such as brain tumors or brain necrosis.

CONCLUSION
Stereotactic radiosurgery is a safe and effective method in the treatment of patients with adrenocorticotropic hormone-producing pituitary tumors, and the effect of treatment is long-lasting. Stereotactic radiosurgery is mainly a complement to microsurgery because of its gradually appearing effect and the occurrence of pituitary insufficiency. New pituitary deficiencies may be found more than 10 years after treatment.
Surgical Management of Isolated Hemangioblastomas of the Spinal Cord
Authors: Roonprapunt Chanland , Silvera V. Michelle , Setton Avi , Freed Diana , Epstein Fred J. , Jallo George I. 
Published: July 2004

Abstract

OBJECTIVE
Intramedullary hemangioblastomas are rare tumors, accounting for just 3% of all intraspinal neoplasms. The purpose of this study is to define the occurrence of isolated intramedullary hemangioblastomas and to analyze the role of the radiological studies and surgery for these lesions.

METHODS
The charts of 19 consecutive patients operated on for isolated spinal intramedullary hemangioblastoma were reviewed. Preoperatively, all patients underwent magnetic resonance imaging and nine underwent spinal angiography. For all patients, the surgical approach was via posterior laminectomy.

RESULTS
Our study sample comprised 6 women and 13 men, with an average age of 31.5 years (range, 16–75 yr). The mean prodrome was 20.8 months. Pain was the most common complaint. In all cases, the neoplasms were associated with a syrinx or edema. Gross total resection was achieved in all patients. At last follow-up examination (mean, 50.1 mo), 13 patients (68%) had improved and 6 patients (32%) had stabilized as compared with their preoperative clinical status.

CONCLUSION
Isolated intramedullary hemangioblastomas typically have an indolent clinical course. These tumors have characteristic imaging properties on magnetic resonance imaging and angiography. Surgical removal of these lesions results in excellent long-term functional outcome.
Nuances in Acoustic Neuroma Surgery
Authors: Malis Leonard I. 
Published: July 2004

Abstract
THIS ARTICLE DESCRIBES surgical methods developed during my resection of 600 acoustic neuromas, 599 of which were total removals. This series began in 1965, with the introduction of the surgical microscope and the development of microsurgical technique. In the 1960s, there was no established technology for the microsurgery of acoustic neuromas. Much of the work of the great early neurosurgeons—Cushing, Dandy, Olivecrona, and other remarkable pioneers—did not really apply. New approaches, solutions, and tools were introduced at that time, and there was a long, steep learning curve. I hope that some of the discussion herein makes learning easier for the new generation of neurosurgeons as they develop their own operative nuances.
Three-dimensional Computed Tomographic Cranial Base Measurements for Improvement of Surgical Approaches to the Petrous Carotid Artery and Apex Regions
Authors: Villavicencio Alan T. , Leveque Jean-Christophe , Bulsara Ketan R. , Friedman Allan H. , Gray Linda 
Published: July 2004

Abstract

OBJECTIVE
The bony and vascular anatomic features in the region of the petrous apex can vary significantly. These variations affect the operative view obtained via extended subtemporal or anterior transpetrosal approaches to cranial base lesions for individual patients. The goal of this study was to evaluate three-dimensional computed tomography as a means of obtaining detailed preoperative anatomic information regarding bony and vascular landmarks and spatial relationships in the region of the petrous carotid artery and petrous apex.

METHODS
We radiographically studied 15 patients (30 sides), using 0.8- to 1-mm-thick, reconstructed, computed tomographic images. Special attention was given to the course of the petrous carotid artery.

RESULTS
The petrous carotid artery was located lateral to the trigeminal impression. The size of the petrous apex medial to the horizontal petrous carotid artery was observed to be variable. The width of bone from the trigeminal impression to the wall of the internal auditory canal averaged 9.6 mm (range, 5.2–16.1 mm). A variable amount of bone overlying the internal auditory canal (4.5 mm) was also present. Multiple other relationships among key landmarks were quantified.

CONCLUSION
There is significant variability in the anatomic features of the petrous apex among patients. For each patient, detailed preoperative information regarding the amount of bone to be removed during a cranial base procedure can be obtained using three-dimensional computed tomography. This information may be critical for determination of the amount of extra exposure that can be achieved via an anterior petrosectomy for each patient.