摘要:

&NA;The effect of altering the volume and timing of hemorrhage on the severity of spasm was studied in a canine model. All animals received three cisterna magna injections of fresh unheparinized autologous arterial blood. Selective left vertebral arteriograms were obtained during the week before and exactly 7 days after the initial subarachnoid injection. Increasing volumes of hemorrhage (from 9 to 15 ml of blood) delivered over 24 hours produced increasingly more severe arterial spasm, with reductions in basilar artery diameter of 37% ± 14 (SD) and 58% ± 15, respectively. Delay of the final injection of blood to 96 hours in the 15‐ml hemorrhage group resulted in even more intense spasm, with an average 71% ± 12 reduction in basilar artery diameter. Serial angiographic evaluation demonstrated the resolution of spasm in this group over approximately 3 weeks. Finally, small, late rebleeding episodes resulted in the rapid onset of intense spasm. Our results support the clinical impression of previous studies that the severity of spasm is related to the volume of hemorrhage and, in addition, suggest that the time course of hemorrhage may play a significant role in determining the overall severity of chronic cerebral vasospasm. (Neurosurgery18:1‐6, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;Operative morbidity, including osteomyelitis and meningeal and cerebral sepsis, remains high among patients undergoing the composite (bony and overlying soft tissue) resection of malignant skull base tumors. This is in part because of the poor wound healing afforded by free skin grafts and the poorly vascularized pericranial flaps routinely used to resurface the operative defect. In an effort to reduce the operative morbidity, single stage resection and reconstruction with distant vascularized flap tissue was performed in five consecutive patients who presented with malignant skull base tumors. We think that immediate flap reconstruction will allow skull base lesions previously considered unresectable or associated with a prohibitive complication rate to be safely resected. Case presentations illustrate operative techniques. The potential disadvantage of masking a tumor recurrence with immediate flap coverage is discussed. (Neurosurgery18:7‐11, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;The incidence of hydrocephalus and vasospasm and the relationship between them were analyzed retrospectively in 87 patients with subarachnoid hemorrhage from ruptured intracranial aneurysms. Sixty‐seven per cent of the patients showed ventricular enlargement on a computed tomographic scan done within 30 days of the hemorrhage; in patients whose first scan was done within 3 days of the hemorrhage, 63% seemed to have ventricular enlargement by a neuroradiologist's interpretation. Shunts were required in 14% of the patients because of delayed neurological deterioration or enlarging ventricles; 3% required ventriculostomy shortly after admission. Seventy‐four per cent of the patients had angiographic spasm on an angiogram done within the first 30 days after hemorrhage. Sixty‐two per cent of the patients had both hydrocephalus and vasospasm: 22% had neither. Five per cent had hydrocephalus, but no spasm; 11% had spasm. but no hydrocephalus. Hydrocephalus and vasospasm were significantly associated (P< 0.01, x2). These data document a high incidence of mild ventricular enlargement and angiographic vasospasm after subarachnoid hemorrhage. They also emphasize that these two sequelae of subarachnoid hemorrhage are closely linked, probably by the presence of blood in the basal cisterns obstructing cerebrospinal fluid flow and surrounding arteries there. (Neurosurgery18:12‐16, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;The main purposes of this study were to evaluate pressure‐volume relations and cerebrospinal fluid (CSF) dynamics in patients with head injury and to evaluate the pressure‐volume index (PVI) in that context. Sixteen head‐injured patients underwent (a) continuous intracranial (intraventricular) pressure (ICP) monitoring, (b) studies of the PVI and the width of the pulse amplitude, and (c) studies of CSF dynamics determined by the PVI technique or controlled withdrawal and expressed as resistance to the outflow of CSF (Rout). In this study, the PVI technique proved safe and relatively simple. The PVI based on bolus injections was significantly greater than the PVI based on CSF withdrawal. The PVI varied independently of clinical course, outcome, and ICP. The ICP pulse amplitude increased linearly with the ICP. It was not possible to establish any clinically useful correlation between pulsatile ICP changes and intracranial compliance (PVI). There was a linear correlation between ICP and Rout. (Neurosurgery18:17‐24, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;We evaluated the ability of intermittent external pneumatic calf compression to prevent deep venous thrombosis after subarachnoid hemorrhage from ruptured intracranical aneurysms. Fifty‐six subarachnoid hemorrhage patients not given external pneumatic calf compression were compared with 90 patients who had calf compression after their subarachnoid hemorrhages. Both groups of patients were on strict bedrest for 7 to 21 days after aneurysm rupture, and both received e‐aminocaproic acid, 30 to 36 g/day intravenously, until operation. The risk factors in the two groups were similar, and the nursing and medical care did not seem to differ. Of patients without external pneumatic compression, 18% had venographically proven deep venous thrombi, which contrasts with 6% of patients receiving calf compression. This was a significant difference (p< 0.05; x2). These retrospective data suggest that external pneumatic calf compression helps to prevent deep venous thrombosis in patients with subarachnoid hemorrhage when delayed operation, bedrest, and antifibrinolytic agents are used. (Neurosurgery18:25‐28, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;The presence of intracranial aneurysm in association with arteriovenous malformation has been well documented. Aneurysms have been described in typical proximal sites along the feeding system to the arteriovenous malformation, in abnormal distal locations along feeding vessels, and in sites remote and apparently hemodynamically unrelated to the arteriovenous malformation. Little attention has been focused on the most appropriate medical and surgical care of patients harboring these lesions. Since 1977, 22 patients with this combination of lesions have been evaluated at our institution. Nine patients (41%) presented after intracranial hemorrhage. The remaining 13 patients were investigated because of seizures in 5 patients (23%), headaches in 4 patients (18%), and progressive ischemia in 4 patients (18%). Among the patients suffering intracranial hemorrhage, 78% had bled from an aneurysm, with 22% having hemorrhaged from their arteriovenous malformation. All 7 of the patients who suffered aneurysmal hemorrhage bled from atypical distal aneurysms on major feeding vessels. Our experience and that of others has led us to believe that the safest approach to patients with this combination of lesions is to treat the aneurysm before microsurgical resection of the associated arteriovenous malformation. Hemodynamic changes associated with the abrupt elimination of an arteriovenous malformation may place associated aneurysms at immediate risk. (Neurosurgery18:29‐35, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;The effects on cerebral metabolism and the electroencephalogram (EEG) of combining hypocapnia with hypotension have been only incompletely examined. The present study examined the possibility that hypocapnia may worsen the cerebral metabolic and EEG disturbances caused by hypotension. Cerebral metabolism and the EEG were studied at three levels of hypotension during hypocapnia (PaCO2= 20 mm Hg) in dogs under light halothane anesthesia. A sequential decrease of the mean arterial pressure (MAP) to 60, 50, and 40 mm Hg (30 minutes at each level) was achieved with sodium nitroprusside (SNP) (n = 12) or trimethaphan (TMP) (n = 12). With SNP‐induced hypotension plus hypocapnia, the power of the &agr; and &bgr;2spectra of the EEG decreased at MAP ≤ 60 mm Hg. Cerebral metabolic values were unchanged at a MAP of 60 or 50 mm Hg. Brain tissue phosphocreatine and the cerebral energy charge decreased, and the lactate/pyruvate ratio increased at a MAP of 40 mm Hg. With TMP‐induced hypotension plus hypocapnia, power decreased in the &agr; and &bgr;2spectra of the EEG at MAP ≤ 60 mm Hg. Cerebral metabolic values were unchanged at a MAP of 60 mm Hg. At MAP ≤ 50 mm Hg, power in the &bgr;1spectrum, brain tissue phosphocreatine, and the cerebral energy charge all decreased. At a MAP of 40 mm Hg, the cerebral glucose value decreased and the lactate/pyruvate ratio increased. The cerebral metabolic and EEG consequences of hypotension plus hypocapnia observed here were similar to those previously reported to occur with SNP‐ or TMP‐induced hypotension at a normal PaCO2. In these studies, hypocapnia did not intensify the cerebral impact of SNP‐ or TMP‐induced hypotension. (Neurosurgery18:36‐44, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;Thirty‐five patients who had incurred head trauma were studied with computed tomography (CT) and magnetic resonance imaging (MRI). CT was performed using a General Electric 8800 scanner. MRI was conducted with a Technicare Teslacon system using a 5.0 kG (0.5 T) magnetic field. Clinically, patients varied from those with mild concussions without focal neurological signs to those with severe neurological dysfunction including posttraumatic coma. MRI was superior to CT in imaging 23 of 41 extracerebral fluid collections, both in estimating the size of the collections and in diagnosing small collections. MRI was also superior to CT in distinguishing chronic subdural hematomas from hygromas. Further, MRI was superior to CT in visualizing nonhemorrhagic contusion in 15 of 21 lesions. Because of the potential failure of MRI to diagnose acute subarachnoid or acute parenchymal hemorrhage, CT remains the procedure of choice in diagnosing head injury less than 72 hours old. (Neurosurgery18:45‐52, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;Three‐dimensional (3D) images were reconstructed from axial computed tomographic scans using the new 3D83 (General Electric Co.) software. Images were reformatted as a movie in multiple frames, each consisting of a discrete 3D scene, and were rotated 360° in 3D space. Improvement in shading and surface algorithm has been made from the previous 3D82 program so that 3D images now have a realistic appearance. Soft tissue and bone modes are available; the latter reconstructs best in 3D because of its high density pixels, which provide a more exclusive threshold. 3D reconstructions of the spine were the most rewarding because the complex anatomy of the spine seems to be best suited for 3D imaging. By hemisection of the spine by subregion, the intervertebral foramina can be evaluated for stenosis. Some drawbacks in this program are the need for user interaction, the lengthy time of reconstruction, and the dependence on high quality axial images. (Neurosurgery18:53‐58, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID

摘要:

&NA;Lesions of the peripheral part of the trigeminal nerve may cause trigeminal neuropathy associated with severe pain. Such pain usually does not respond to carbamazepine and analgesics, and it is continuous and lacks the characteristic paroxysmal character of tic douloureux. These patients often present with complex changes of facial sensibility in the form of dysesthesia, hyperalgesia, and allodynia. The pain sometimes responds favorably to transcutaneous nerve stimulation, but direct stimulation of the trigeminal ganglion and rootlets via an implanted electrode provides a greater likelihood of pain relief. Fourteen patients diagnosed as having painful trigeminal neuropathy received implants of a gasserian ganglion‐stimulating electrode. The mean follow‐up period is 4 years (range, 1 to 7 years). Eleven of the patients have retained the pain‐relieving effect, and 1 had pain disappear without further stimulation. Eight of the patients estimated their pain relief to be complete or very good. There were no serious complications, but in several of the patients the electrode had to be exchanged because the insulation of the lead wires broke. For the selection of patients for permanent electrode implantation, a method has been developed for trial stimulation via a percutaneous electrode introduced into the trigeminal cistern. Temporary trial stimulation can be performed for several days. It is concluded that stimulation of the trigeminal ganglion and rootlets with the aid of an implanted electrode may effectively relieve certain forms of trigeminal pain that are otherwise extremely difficult to manage. (Neurosurgery18:59‐66, 1986)

ISSN:0148-396X    

出版商:OVID    

年代:1986

数据来源: OVID