摘要:

THE ANTERIOR APPROACH to the thoracic and lumbar spine for neoplastic disease is now a well-accepted procedure, with results, for the most part, superior to those achieved with laminectomy. However, the specific indications for anterior decompression and the selection of reconstruction techniques based on the location and extent of bony destruction have received surprisingly little attention. The authors report their experience with the operative management of 33 patients with benign and malignant tumors of the thoracic and lumbar spine, using the anterior transthoracic or retroperitoneal approach. The role of stabilization and the relative indications for anterior or posterior instrumentation are emphasized. The mean age of patients was 58 years. Twenty-three patients were male. Five patients had benign tumors, and the remainder had a variety of metastatic lesions. Twenty-nine patients had lower extremity motor deficits, although 25 were ambulatory preoperatively. Thirty-seven noncontiguous resections were performed in 33 patients. In 13 patients, the resected vertebral body was replaced with acrylic or bone without instrumentation; in 18, the acrylic was supplemented with anterior instrumentation; and in 6, both anterior and posterior instrumentation were used. Above T11, vertebral reconstruction techniques were used to restore stability after decompression. Between T11 and L4, anterior instrumentation was used to supplement vertebral reconstruction in all patients. Supplemental posterior instrumentation was used for three-column involvement. Motor function was stabilized or improved in 94% of patients, and 88% of patients were ambulatory postoperatively. Of 28 patients with malignant disease, 23 died after a mean survival of 10.2 months (range, 2–51 mo) and 5 are alive a mean of 34.4 months since their operation. There were no instrumentation failures, and alignment was maintained in all patients. The authors emphasize that the necessity for instrumentation and the type of instrumentation employed depends on the extent and location of bony destruction. Correct patient selection for operative therapy and the appropriate application of anterior or posterior instrumentation are essential for optimizing results.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

WE PROSPECTIVELY STUDIED 712 consecutive patients during a 1-year period who presented with amnesia or loss of consciousness after nonpenetrating head trauma and who had a perfect Glasgow Coma Scale score of 15. Of the 67 (9.4%) patients with acute traumatic lesions disclosed by computed tomography (CT) of the head, 2 required neurosurgical intervention and 1 died. Four factors were statistically correlated (P< 0.05) with abnormal CT findings: Older age, white race, signs of basilar skull fracture, and being either a pedestrian hit by a motor vehicle or a victim of an assault. Sex, length of antero- or retrograde amnesia, forward and reverse digit spans, object recall, focal abnormality on the general neurological exam, and subjective complaints were not statistically correlated with CT abnormality. Using step-wise discriminant function analysis, no single item or combination of items could be used to classify 95% of the patients into either the normal or abnormal CT group. Therefore, regardless of age, mechanism of injury, or clinical findings, intracranial lesions cannot be completely excluded clinically on head-trauma patients who have loss of consciousness or amnesia, even if the Glasgow Coma Scale score is 15. However, only two patients (0.3%) required neurosurgical intervention.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

THE LONG-TERM COURSE of intracranial pressure (ICP) was studied in 53 patients from a group of 90 patients with severe head injury treated over a 3-year period. In 49 of these, ICP was significantly elevated during the observation period. The maximum in ICP was usually observed 24 to 96 hours posttrauma. A subgroup of patients developed a second rise of ICP. Such a course was observed in 15 (31%) of the 49 patients with intracranial hypertension. In these cases, ICP increased initially to 20 to 30 mm Hg but could be controlled. Thereafter, ICP was decreased again for at least 12 hours. The secondary ICP rise occurred 3 to 10 days after trauma. In six patients, intracranial hypertension became uncontrollable and eventually caused brain death. The outcome of patients with a secondary rise of ICP was worse when compared with that of patients without this complication. A cause of the secondary ICP rise could only be identified in some cases. Delayed traumatic intracerebral hemorrhage, traumatic vasospasm, hypoxia, and hyponatremia were diagnosed in seven cases. In seven other patients, the secondary ICP rise coincided with a pronounced leukocytosis, which was not associated with apparent infections. Because the occurrence and degree of a secondary rise of ICP after severe head injury are important factors affecting outcome, monitoring of ICP after severe head injury should be prolonged.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

THE IMPORTANCE OF delayed or secondary brain insults in the eventual outcome of closed-head trauma has been documented in experimental models. To understand this phenomenon in the clinical setting, we studied a series of head-injured patients in whom multiple cranial computed tomographic (CT) scans were obtained. Patients whose follow-up CT studies revealed new intracranial lesions or worsening, compared with admission findings, were considered to have delayed cerebral injury. One hundred forty-nine (44.5%) of 337 consecutively studied patients developed delayed brain injury. There were highly significant associations (P< 0.001) between the appearance of delayed cerebral insults and the severity of the initial brain injury, the need for cardiopulmonary resuscitation in the field, the presence of coagulopathy at admission, and subdural hematoma on the initial CT scan. In addition, delayed injury was associated (P< 0.001) with higher mortality, slowed recovery, and poorer outcome at 6 months. Delayed brain injury was not significantly associated with patient age, sex, injury mechanism, associated injury, the need for endotracheal intubation in the field, early talking, CT abnormality other than intracranial hematoma, or type of residual neurological deficits. We used multiple regression analysis to explore the relationship between severity of injury, delayed insults, and outcome. As expected, the severity of the initial brain trauma contributed significantly to neurological outcome. The presence of delayed cerebral injury makes the outcome dramatically worse for each category of initial injury severity. The relationship between initial and secondary brain injury is discussed.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

OF 200 PATIENTS with acoustic neurinoma undergoing an operation via the retrosigmoid transmeatal approach in the semisitting position, 18 patients had a high jugular bulb on the tumor side. The frequency was 9%. From a neurosurgical point of view, a jugular fossa above the low border of the internal auditory canal (IAC) is classified as a high one. All 200 patients were evaluated by computed tomography with bone window reconstruction of high-resolution thin axial slices (1.5 mm). High jugular bulbs were classified into three grades as follows: Grade I, jugular bulb situated less than 1.5 mm above the low border of IAC; Grade II, jugular bulb between 1.5 and 3.0 mm above the low border of the IAC; Grade III, jugular bulb >3 mm above the low border of IAC. There were eight patients with Grade I, six patients with Grade II, and four patients with Grade III. In these patients, in order to open the IAC without concomitant injury of the jugular bulb, the superior posterior portion of the porus was drilled away. Opening the jugular fossa was unavoidable in Grade III cases. No difference was noted in functional preservation of facial or cochlear nerve between HJB cases and normal jugular bulb cases, but HJB cases had a higher frequency of air embolism during tumor removal than did normal cases (16 versus 5%), especially Grade III cases (two of four). There was no mortality or morbidity in the cases of air embolism. Details of the surgical procedure in such cases are discussed.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

TWENTY-TWO SURGICALLY TREATED infratentorial ependymomas were analyzed according to their anatomical origins and characteristics of extension in conjunction with the microsurgical anatomy of the fourth ventricle. The correlation between tumor origin and postoperative survival of the patients was also assessed. The tumors were classified into three types according to their origins and extensions: 1) midfloor-type: tumors originating from the caudal half of the fourth ventricular floor beneath the striae medullares. After occupying the fourth ventricular cavity, they extended downward through the foramen Magendie to the upper cervical level. 2) Lateral type: tumors arising from the vestibular area and/or the lateral recess. They grew not only inferiorly but also laterally to the cerebellomedullary cistern through the cerebellomedullary fissure and the foramen of Luschka. 3) Roof type: tumors originating from the roof of the ventricle. The overall cumulative survival rates at 2, 5, and 10 years were 84, 62, and 47%, respectively. Interestingly, the lateral-type tumors showed a significantly lower 5-year cumulative survival rate and mean survival time (21% and 40 months) when compared with midfloor-type tumors (73% and 170 months). Because the tumor originates near the vital neural structures and because each type has characteristics of extension, a clear knowledge of the microanatomical relationship between the tumor and the surrounding structures would be of great benefit for improving the operative outcome of posterior fossa ependymomas.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

TO MONITOR THE course of infectious intracranial aneurysms, repeated cerebral angiography has been recommended every 2 weeks during intravenous antibiotic therapy until the aneurysm has resolved or an operation has been performed. However, serial cerebral angiograms are not without some risk to the patient. We have prospectively studied five patients harboring a total of six infectious intracranial aneurysms by sequential computed tomography (CT) and/or magnetic resonance imaging (MRI) studies. All infectious aneurysms were initially identified by cerebral angiography and were treated with 6 to 8 weeks of intravenous antibiotics. The aneurysm size ranged from 4 to 10 mm. Sequential CT scans and/or MRI studies were obtained at 2- to 3-week intervals to monitor the course of the aneurysms. Three aneurysms enlarged during antibiotic therapy, and one remained unchanged in size. These four aneurysms were treated surgically. The two remaining aneurysms resolved with intravenous antibiotic therapy. Cerebral angiograms were obtained routinely preoperatively and were used to verify the resolution of the infectious aneurysms when they were no longer visible on CT or MRI. On the basis of this prospective study, we conclude that sequential thin-slice CT and/or MRI can effectively and safely monitor the course of infectious intracranial aneurysms once identified by cerebral angiography. This may reduce the need for serial angiography and reduce the ultimate risk in the management of infectious intracranial aneurysms.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

A FRAMELESS COMPUTERIZED navigating system was successfully employed in 20 cases of open microsurgical operations on deep-seated brain tumors and vascular malformations. Localization in space was made by measuring the traveling time of sonic waves (24 kHz) in air. This allowed the construction of mechanically simple, lightweight freehand targeting instruments. The tips can be localized with a measuring accuracy of ± 1 mm intracranially on the basis of computed tomographic scans. This thoroughly redesigned sonic stereometrical device is being optimized for everyday use; magnetic resonance imaging, digital substraction angiography, and other diagnostic modalities will be implemented. Some perspectives on “computer-aided (neuro)surgery” are discussed.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

THE OXIDIZED BREAKDOWN products of hemoglobin are important in the pathogenesis of cerebral vasospasm because of their effects on the endothelium and the smooth muscle of the arterial wall. Cytoskeletal changes in cultured vascular cells are sensitive indicators of oxidative injury. Cultured endothelial cells and smooth muscle cells showed a dose-related disruption of the cytoskeleton, particularly the F-actin and vimentin filaments, when exposed to 10−5M oxyhemoglobin. The cytoskeletal injury was prevented by the addition of 10−3M deferoxamine or 1% albumin. These experiments support a role for deferoxamine in the pharmacological treatment of vasospasm. Furthermore, cytoskeletal studies of cultured arterial endothelial and smooth muscle cells provide a novel in vitro approach by which to study the cellular mechanisms of oxidant injury initiated by the breakdown products of hemoglobin.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

WE INVESTIGATED THE natural course of the morphological regeneration of the endothelium and smooth muscle of the rat carotid artery after clipping injury. Vascular damage was produced by clipping the right carotid arteries of Wistar rats. Endothelial regeneration was confirmed by the injection of Evans blue dye and the detection of factor VIII-related antigen. The volume of the smooth muscle cell layer and the luminal size were measured by computer-assisted morphometric analysis. Immediately after arterial injury, Evans blue dye freely permeated the smooth muscle layer, suggesting that complete endothelial denudation had occurred. Endothelial regrowth started within 24 hours and was fastest on the third and fourth days after injury. The endothelial injury was repaired within 5 days. The area of the smooth muscle layer did not change immediately after clipping injury, but it gradually increased within a month. The luminal area of the injured artery increased during the 3-month recovery period. These findings suggest that endothelial regrowth is completed within a week after clipping injury, whereas smooth muscle cell regrowth is slower. In addition, arteriosclerotic luminal narrowing did not occur during recovery of the rat carotid artery from clipping injury.

ISSN:0148-396X    

出版商:OVID    

年代:1993

数据来源: OVID