bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymptomatic versus Symptomatic Infarcts from Vasospasm in Patients with Subarachnoid Hemorrhage: Serial Magnetic Resonance Imaging
Authors: Shimoda Masami , Takeuchi Masataka , Tominaga Jiro , Oda Shinri , Kumasaka Akira , Tsugane Ryuichi 
Published: July 2004

ABSTRACT

OBJECTIVE
By use of serial magnetic resonance imaging (MRI), we prospectively investigated the incidence of and the risk factors associated with infarction caused by vasospasm with or without a delayed ischemic neurological deficit (DIND) in patients with subarachnoid hemorrhage (SAH).

METHODS
In 125 patients who underwent surgery for early aneurysms, postoperative MRI scans were obtained at four time points. We defined an infarct from vasospasm as a new lesion not present on the initial MRI within 3 days after SAH and therefore not attributable to primary brain damage or surgical complications.

RESULTS
Overall, symptoms of infarction (i.e., DIND) occurred in 38% of patients (48 of 125); DIND with a new infarct on MRI was evident in 34% (43 patients), whereas 4% (5 patients) showed no new lesion but had a DIND. However, 29 patients (23%) showed a new infarct but no DIND on MRI studies (asymptomatic infarction). Asymptomatic ischemic lesions due to vasospasm tended to involve noneloquent brain areas in the territory of intraparenchymal perforators. Multivariate analysis identified variables associated with symptomatic infarction to be of poor SAH grade, advanced age of the patient, angiographic findings of vasospasm, multiple cortical infarcts on MRI studies consistent with vasospasm, and chronic hydrocephalus.

CONCLUSION
Analysis of the data confirmed the occurrence of asymptomatic infarcts due to vasospasm. These infarcts often developed in noneloquent areas representing perforator territory. MRI investigation of vasospastic lesions referable to intraparenchymal vessels such as perforators complements the study of extraparenchymal major vessel vasospasm in patients with SAH by computed tomographic angiography.
Management of Spontaneous Cerebellar Hematomas: A Prospective Treatment Protocol
Authors: Kirollos Ramez W. , Tyagi Atul K. , Ross Stuart A. , van Hille Philip T. , Marks Paul V. 
Published: July 2004

ABSTRACT

OBJECTIVE
To identify easily applicable guidelines for the surgical and conservative management of spontaneous cerebellar hematomas.

METHODS
A treatment protocol was developed and prospectively applied for the management of 50 consecutive cases of cerebellar hematomas. The appearance of the fourth ventricle, adjacent to the hematoma, on computed tomographic scans was divided into three grades (normal, compressed, or completely effaced). The degree of fourth ventricular compression was correlated with the size and volume of the hematoma and the presenting Glasgow Coma Scale (GCS) score. The hematoma was surgically evacuated for all patients with Grade III compression and for patients with Grade II compression when the GCS score deteriorated in the absence of untreated hydrocephalus. Patients with Grade I or II compression were initially treated with only ventricular drainage in the presence of hydrocephalus and clinical deterioration.

RESULTS
The degree of fourth ventricular compression was classified as Grade I in 6 cases, Grade II in 26, and Grade III in 18. The degree of fourth ventricular compression was significantly correlated with the volume of the hematoma (rs = 0.67, P &lt; 0.0001), hydrocephalus (rs = 0.44, P = 0.001), the preoperative GCS score (rs = 0.43, P = 0.001), the maximal diameter of the hematoma (rs = 0.43, P = 0.001), and a midline location of the hematoma (χ2 = 6.84, P &lt; 0.009). Acute deterioration in GCS scores occurred for 6 (43%) of 14 patients with Grade III ventricular compression who were conscious at presentation. Thirteen patients with Grade I or II ventricular compression and stable GCS scores of more than 13 were treated conservatively. Nine patients were treated with ventricular drainage only, and 28 underwent posterior fossa craniectomy and evacuation of the hematoma with ventricular drainage. The mortality rate at 3 months was 40%. None of the patients with Grade III fourth ventricular compression and GCS scores of less than 8 at the time of treatment experienced good outcomes. Overall, 15 (60%) of 25 patients with hematomas with maximal diameters of more than 3 cm and Grade I or II compression did not require clot evacuation.

CONCLUSION
Conscious patients with Grade III fourth ventricular compression should undergo urgent clot evacuation before deterioration. Surgical evacuation of the clot may not be required for large hematomas (&gt;3 cm) if the fourth ventricle is not totally obliterated at the level of the clot.
Surgical Pathology of Spinal Schwannomas: A Light and Electron Microscopic Analysis of Tumor Capsules
Authors: Hasegawa Mitsuhiro , Fujisawa Hironori , Hayashi Yutaka , Tachibana Osamu , Kida Shinya , Yamashita Junkoh 
Published: July 2004

ABSTRACT

OBJECTIVE
Although spinal schwannomas are often encountered, the pathology of the tumor capsule has not been reported. In this study, we describe the ultrastructural pathology of the tumor capsule of spinal schwannomas.

METHODS
In 18 patients who underwent total removal of spinal schwannomas (C2–conus), the tumor capsule was collected and examined by light and electron microscopy.

RESULTS
The thickness of the tumor capsule ranged from 15 to 800 μm (mostly 30–100 μm) and was composed of three layers from the surface to the center: 1) a thinly stretched nerve tissue layer; 2) a fibrous layer of fibrocytes, abundant collagen fibers, and tumor vessels; and 3) a thin transitional layer intermingled with fibrous components and tumor cells. The thickness of each layer varied in different regions of the surface. There was no clear separation between the tumor capsule and the neoplastic tissue, even on the electron microscopic level. A number of nerve fibers ran through the fibrous layer and beneath the capsule as well as in the nerve tissue layer.

CONCLUSION
Compared with vestibular schwannomas, which have been reported to be covered by an extremely thin layer (3–5 μm) of connective tissue, spinal schwannomas were well encapsulated. The capsule was composed of three distinct components; however, the cleavage between thin capsule and tumor cells was indistinct, and the thickness of the axon-containing capsule varied from site to site. Therefore, resection of the nerve of tumor origin, rather than enucleation, would be justified to avoid tumor recurrence. Surgeons should be aware of this pathology when performing the procedure.
Can Diffusion- and Perfusion-weighted Magnetic Resonance Imaging Evaluate the Efficacy of Acute Thrombolysis in Patients with Internal Carotid Artery or Middle Cerebral Artery Occlusion?
Authors: Uno Masaaki , Harada Masafumi , Yoneda Kazuhide , Matsubara Shunji , Satoh Koichi , Nagahiro Shinji 
Published: July 2004

ABSTRACT

OBJECTIVE
The value of combined diffusion-weighted imaging (DWI) and perfusion-weighted imaging (PWI) for detecting ischemic lesions of patients with acute ischemic injury was analyzed. Combined pre- and posttreatment DWI and PWI studies were used to assess the efficacy of intra-arterial thrombolysis.

METHODS
Intra-arterial thrombolysis was performed within 6 hours of onset in 10 patients who presented with acute middle cerebral artery or internal carotid artery occlusion. DWI and PWI obtained before and after treatment were studied. The final T2-weighted magnetic resonance scans were obtained 1 month after onset. Thrombolysis resulted in recanalization in seven patients. The mismatch ratio percentage ([initial PWI − initial DWI/initial PWI] × 100) and the rescued ratio percentage ([initial PWI − final T2/initial PWI] × 100) were calculated. The National Institutes of Health Stroke Scale (NIHSS) was used for neurological assessment of stroke severity at admission and at 1 month after onset.

RESULTS
In all patients, the mismatch ratio was greater than 60% (mean ± standard deviation, 81.7 ± 16.7%) and was significantly correlated with initial NIHSS score (−0.74;P = 0.03), and the rescued ratio was significantly correlated with the NIHSS score 1 month after the insult (r = −0.83;P = 0.01). In patients who exhibited recanalization of the occluded artery (n = 7), the mean rescued ratio was 89.6 ± 12.8% (range, 63–100%). In addition, the lesion volume on posttreatment DWI scans and final T2-weighted magnetic resonance images was not enlarged; on posttreatment PWI scans, it was significantly decreased. The NHISS score at 1 month after the insult (2.3 ± 2.1) was markedly improved as compared with the initial NHISS score (10.7 ± 3.9).

CONCLUSION
In a small number of patients who presented with internal carotid artery or middle cerebral artery occlusion, the DWI/PWI mismatch ratio correlated with the initial neurological severity. The rescued ratio may be an objective indicator of the efficacy of treatment.
Gamma Knife Stereotactic Radiosurgery for Patients with Glioblastoma Multiforme
Authors: Nwokedi Emmanuel C. , DiBiase Steven J. , Jabbour Salma , Herman Joseph , Amin Pradip , Chin Lawrence S. 
Published: July 2004

ABSTRACT

OBJECTIVE
Stereotactic radiosurgery (SRS) has become an effective therapeutic modality for the treatment of patients with glioblastoma multiforme (GBM). This retrospective review evaluates the impact of SRS delivered on a gamma knife (GK) unit as an adjuvant therapy in the management of patients with GBM.

METHODS
Between August 1993 and December 1998, 82 patients with pathologically confirmed GBM received external beam radiotherapy (EBRT) at the University of Maryland Medical Center. Of these 82 patients, 64 with a minimum follow-up duration of at least 1 month are the focus of this analysis. Of the 64 assessable patients, 33 patients were treated with EBRT alone (Group 1), and 31 patients received both EBRT plus a GK-SRS boost (Group 2). GK-SRS was administered to most patients within 6 weeks of the completion of EBRT. The median EBRT dose was 59.7 Gy (range, 28–70.2 Gy), and the median GK-SRS dose to the prescription volume was 17.1 Gy (range, 10–28 Gy). The median age of the study population was 50.4 years, and the median pretreatment Karnofsky performance status was 80. Patient-, tumor-, and treatment-related variables were analyzed by Cox regression analysis, and survival curves were generated by the Kaplan-Meier product limit.

RESULTS
Median overall survival for the entire cohort was 16 months, and the actuarial survival rate at 1, 2, and 3 years were 67, 40, and 26%, respectively. When comparing age, Karnofsky performance status, extent of resection, and tumor volume, no statistical differences where discovered between Group 1 versus Group 2. When comparing the overall survival of Group 1 versus Group 2, the median survival was 13 months versus 25 months, respectively (P = 0.034). Age, Karnofsky performance status, and the addition of GK-SRS were all found to be significant predictors of overall survival via Cox regression analysis. No acute Grade 3 or Grade 4 toxicity was encountered.

CONCLUSION
The addition of a GK-SRS boost in conjunction with surgery and EBRT significantly improved the overall survival time in this retrospective series of patients with GBM. A prospective, randomized validation of the benefit of SRS awaits the results of the recently completed Radiation Therapy Oncology Group's trial RTOG 93-05.
Laminoplasty with Preservation of Posterior Cervical Elements: Surgical Technique
Authors: Tani Satoshi , Isoshima Akira , Nagashima Yasuhiro , Tomohiko Numoto Robert , Abe Toshiaki 
Published: July 2004

ABSTRACT

OBJECTIVE
We have developed a modified laminoplasty procedure that preserves the posterior cervical elements, and we have used it to treat multilevel cervical canal stenosis, with or without spondylotic changes, in 30 patients.

METHODS
In this procedure, the posterior bony elements, such as the spinous processes, are not completely detached from the ligaments and musculature and are repositioned in the midline, to maintain normal cervical anatomic relationships. Thirty patients (mean age, 55.2 yr) were registered and evaluated in this study, with a mean follow-up period of 18.1 months, between November 1995 and October 2000. The rates of bony union of the reconstructed laminae and alignment of the cervical spine were assessed by using computed tomographic scans and lateral radiographs.

RESULTS
All patients except one noted some improvement in sensation, motor function, or both. Changes in spinal curvature were noted for two patients for whom a kyphotic deformity had developed before surgery (because of S-shaped or straight curvature). The average decrease in the range of motion was 7.26 degrees. Estimated rates of bony fusion at the sites of the gutters, spacers, and spinous processes were 94.6, 62.3, and 86.6%, respectively. A stable bony arch was assumed to be achieved with bony fusion at the gutters on the hinge side, as well as the spinous processes, approximately 6 months after surgery.

CONCLUSION
Our new technique of cervical laminoplasty preserves the posterior musculature and bony elements. This new procedure also helps maintain correct spinal alignment.
Thoracoscopic Microdiscectomy
Authors: Oskouian Rod J. , Johnson J. Patrick , Regan John J. 
Published: July 2004

ABSTRACT
THE THORACOSCOPIC APPROACH for the microsurgical removal of herniated thoracic discs is described, and perioperative management is also discussed. The microsurgical techniques used for decompression of the spinal canal in the thoracic spine are presented in detail. The diagnostic imaging, surgical positioning, approach, port placement, localization of the thoracic level, exposure of the surgical field, excision of the rib head, exposure with removal of the herniated disc, and postoperative management are outlined. Surgical and operative “pearls” in thoracoscopic spinal surgery for removing herniated thoracic discs when possible are described and illustrated.
Human Endothelin Subtype A Receptor Enhancement during Tissue Culture via de Novo Transcription
Authors: Hansen-Schwartz Jacob , Nordström Carl-Henrik , Edvinsson Lars 
Published: July 2004

ABSTRACT

OBJECTIVE
Endothelin (ET) has, since its discovery, increasingly been considered a key player in the pathophysiological processes of cerebral vasospasm in the course of subarachnoid hemorrhage, although it remains unclear how ET is involved. We present data that indicate an inherent capacity of human cerebral arteries to change their sensitivity to ET.

METHODS
Human cerebral arteries were obtained from patients undergoing intracranial tumor surgery. The vessels were divided into segments and subjected to organ culture for 48 hours. The vessels were then examined by using in vitro pharmacological methods and molecular biological techniques.

RESULTS
After organ culture of the cerebral arteries, both the sensitivity to and potency of ET were enhanced (maximal response, 152 ± 9%; −log (50% effective concentration), 10.3 ± 0.3), in comparison with data for fresh cerebral arteries. Contractions were inhibited by both FR139317 (a specific ETA receptor antagonist) and bosentan (a mixed ETA and ETB receptor antagonist), in a manner indicating the sole presence of contractile ETA receptors. An inconsistent dilative response to the selective ETB receptor agonist sarafotoxin 6c was observed; the response was preserved in some segments and abolished in others, and potentiation of the precontraction was observed in yet other segments. No isolated contractile response to sarafotoxin 6c was observed, however. In reverse transcription-polymerase chain reaction assays, both ETA and ETB receptor messenger ribonucleic acid was detected.

CONCLUSION
These results demonstrate that human cerebral arteries are capable of enhancing the function of ETA receptors.
Recurrent Torticollis Caused by Dissecting Vertebral Artery Aneurysm in a Pediatric Patient: Results of Endovascular Treatment by Use of Coil Embolization: Case Report
Authors: Grosso Salvatore , Mostardini Rosa , Venturi Carlo , Bracco Sandra , Casasco Alfredo , Berardi Rosario , Balestri Paolo 
Published: July 2004

ABSTRACT

OBJECTIVE AND IMPORTANCE
Torticollis is a symptom that can be related to different pathological mechanisms ranging from simple to life-threatening conditions. We report a child with recurrent torticollis caused by an intracranial dissecting vertebral artery aneurysm. This is a very rare condition in childhood, and it was resolved successfully with endovascular treatment.

CLINICAL PRESENTATION
The patient was a 10-year-old boy with a 4-year history of left recurrent torticollis, followed by hemiparesis, dysarthria, dysmetria, and tremor. Brain magnetic resonance imaging and digital angiography detected a dissecting aneurysm involving the fourth segment of the left vertebral artery.

INTERVENTION
The patient underwent endovascular treatment. Coil embolization, followed by histoacryl injection into the lesion, provided complete obliteration of the aneurysmal sac.

CONCLUSION
The patient's postoperative course was characterized by a dramatic disappearance of symptoms and signs within a few hours of the intervention. No relapses of symptoms occurred during a follow-up period of 18 months. This is the first report of a child in whom recurrent torticollis was related to a dissecting vertebral artery aneurysm. Although long-term results of vertebral artery coil embolization remain to be elucidated, the method seems reliable and effective in treatment of these vascular lesions in pediatric patients.
Cerebellopontine Angle Epidermoids Presenting with Cranial Nerve Hyperactive Dysfunction: Pathogenesis and Long-term Surgical Results in 30 Patients
Authors: Kobata Hitoshi , Kondo Akinori , Iwasaki Koichi 
Published: July 2004

ABSTRACTOBJECTIVETo provide the characteristics and long-term surgical results of patients who present with cerebellopontine angle epidermoids and trigeminal neuralgia (TN) or hemifacial spasm.METHODSA total of 30 patients (23 women, 7 men) who presented with cerebellopontine angle epidermoids and TN (28 patients) or hemifacial spasm (2 patients) between 1982 and 1995 were reviewed, with emphasis being placed on the clinical manifestations, the mechanisms of symptom development, the long-term follow-up results, and the anatomic relationship between the tumor and the surrounding neurovascular structures.RESULTSThe average age of the patients was 37.8 years at symptom onset and 49.3 years at the time of the operation. The tumor-nerve relationships were classified into four types: complete encasement of the nerve by the tumor, compression and distortion of the nerve by the tumor, compression of the nerve by an artery located on the opposite side of the unilateral tumor, and compression of the nerve by an artery on the same side of the tumor. Total resection was achieved in 17 patients (56.7%). Microvascular decompression of the respective cranial nerve was achieved in nine cases of direct arterial compression in addition to tumor removal. The symptom was relieved completely in all cases. In an average follow-up period of 11.5 years, three patients developed recurrent symptoms: two experienced tumor regrowth, and one had arachnoid adhesion.CONCLUSIONHyperactive dysfunction of the cranial nerves, especially TN, may be the initial and only symptom that patients with cerebellopontine angle epidermoids experience. The occurrence of TN at a younger age was characteristic of TN patients with epidermoids, in contrast to patients with TN due to a vascular cause. The symptom is elicited by compression of the nerve by the tumor per se, by an artery that is displaced to the nerve, or by both. Careful resection of the tumor, whose capsule occasionally is strongly adherent to the neurovascular structures, is necessary, and microvascular decompression to straighten the neuraxis should be performed in some cases to achieve a complete, permanent cure of symptoms with a low rate of recurrence.
Hyperbaric Oxygen Treatment of Postoperative Neurosurgical Infections
Authors: Larsson Agneta , Engström Mats , Uusijärvi Johan , Kihlström Lars , Lind Folke , Mathiesen Tiit 
Published: July 2004

ABSTRACT

OBJECTIVE
To evaluate the clinical usefulness of hyperbaric oxygen (HBO) therapy for neurosurgical infections after craniotomy or laminectomy.

METHODS
The study involved review of medical records, office visits, and telephone contacts for 39 consecutive patients who were referred in 1996 to 2000. Infection control and healing without removal of bone flaps or foreign material, with a minimum of 6 months of follow-up monitoring, were considered to represent success.

RESULTS
Successful results were achieved for 27 of 36 patients, with a mean follow-up period of 27 months (range, 6–58 mo). One patient discontinued HBO therapy because of claustrophobia, and two could not be evaluated because of death resulting from tumor recurrence. In Group 1 (uncomplicated cranial wound infections), 12 of 15 patients achieved healing with retention of bone flaps. In Group 2 (complicated cranial wound infections, with risk factors such as malignancy, radiation injury, repeated surgery, or implants), all except one infection resolved; three of four bone flaps and three of six acrylic cranioplasties could be retained. In Group 3 (spinal wound infections), all infections resolved, five of seven without removal of fixation systems. There were no major side effects of HBO treatment.

CONCLUSION
HBO treatment is an alternative to standard surgical removal of infected bone flaps and is particularly useful in complex situations. It can improve outcomes, reduce the need for reoperations, and allow infection control without mandatory removal of foreign material. HBO therapy is a safe, powerful treatment for postoperative cranial and spinal wound infections, it seems cost-effective, and it should be included in the neurosurgical armamentarium.