摘要:

&NA;Seventy patients suspected clinically of having an acoustic tumor were evaluated using the computed tomographic (CT) scan as the initial neuroradiological procedure, followed by CO2contrast CT cisternography in cases where the intravenous contrast‐enhanced scan did not reveal any lesion. Forty‐eight gas CT cisternograms revealed 10 small acoustic tumors, 2 of which were totally intracanalicular. The authors present a review of the basic CT anatomy of the temporal bone as it relates to acoustic tumors. Based upon the ease of performance of the procedure, the low postexamination morbidity, and the excellent diagnostic results, CO2CT cisternography is recommended as the procedure of choice in the diagnosis of small and intracanalicular acoustic tumors. (Neurosurgery11:733‐738, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Significant rheological, cerebrovascular, and cardiovascular alterations from base line conditions in splenectomized dogs were observed after serial intravascular volume expansion with low molecular weight dextran (MW 40,000). Nine dogs received two infusions of dextran within 120 minutes; each infusion equaled 20% of the respective dog's total blood volume (TBV). The plasma volume (PV) increased 48% and then another 40% after the two respective infusions, while the hematocrit (Hct) was obligatorily reduced by 20% and the 9%. The relative fresh blood viscosity at the shear rate of 10 sec‐1decreased initially 27% and then 6%. The blood viscosity correlated inversely with TBV and PV and varied directly with Hct after these dextran infusions. After two respective dextran infusions, cardiac output (CO) increased initially 43% and then 26% without significant alterations in mean arterial blood pressure. In addition, CO correlated negatively with both Hct and blood viscosity. Although the 14% elevation in regional cortical blood flow (rCoBF) in the territory of the middle cerebral artery did not reach statistical significance, rCoBF correlated inversely with both Hct and blood viscosity and was related directly to TBV, PV, and CO after the dextran infusions. Cortical vascular resistance (CVR) decreased initially 6% and then 5% after the two respective dextran infusions. The CVR was related inversely to PV, but its correlation with blood viscosity did not reach statistical significance. Intracranial pressure (ICP) rose 2‐fold; correlated positively with TBV, PV, and rCoBF; and varied inversely with CVR. Our data suggest that hypervolemic hemodilution with expansion of PV significantly reduces blood viscosity at relatively low shear rates. Fresh blood viscosity seems to be a major factor determining CO and cerebral perfusion after the administration of low molecular weight dextran. Reductions in blood viscosity may account for the direct relationship between rCoBF and CO observed after intravascular volume expansion with hemodiluting agents. Hypervolemic hemodilution with dextran raises ICP, possibly as a function of increased cerebral blood volume resulting from the reduced CVR and the elevated PV. (Neurosurgery11:739‐753, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Six arteriovenous malformations (AVMs) and five arterial aneurysms (AAs) were treated with either argon or neodymium:yttrium‐aluminum‐garnet laser irradiation; one AVM was treated with both. All AVMs were occluded completely, leaving adjacent tissue untouched and preserving the regional vascularization. Photocoagulation produced varying effects on AAs: in one case an intraoperative rupture was sealed, in two cases the volume of an ectasia was reduced when the bleeding and thinner areas were coagulated, and in one case a saccular aneurysm was progressively and completely obliterated while the patency of the parent artery was preserved. These preliminary results are satisfactory; more experience will indicate how and when these new techniques can replace traditional ones or be used in combination with them. (Neurosurgery11:754‐760, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Characteristic features of familial cases of cerebellar hemangioblastom a were analyzed on the basis of 54 patients, 32 male and 22 female. In this group there were 7 cases from five affected families. The overall recurrence rate was 33.3% among patients who had been followed for more than 4 years after total removal of the tumor. Recurrence was more common in the familial cases (50%). The average age at the onset of symptoms was younger (23.4 years) in familial cases than in nonfamilial cases (36.2 years) and tended to be even younger (18.9 years) in the second generation of familial cases. These findings suggest that the integration of primitive vasoformative tissues is disturbed more severely in familial cases of cerebellar hemangioblastoma. (Neurosurgery11:761‐763, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Neck clipping has generally been believed to be among the most reliable of the operative modalities for cerebral aneurysm. However, recurrences with catastrophic outcome have been known to occur. We recently treated two patients who each had a new aneurysm at the site of the initial clipping. In both cases, the recurrence was found several years after the aneurysm neck had been closed successfully with a silver clip, which had been confirmed by intraoperative inspection and by postoperative angiographic studies demonstrating disappearance of the aneurysm. Histological examination of the recurrent aneurysm showed that the arterial wall had apparently been damaged by the clip edge, which resulted in thinning and disruption of both the muscle layer and the internal elastic lamina. Therefore, local fragility of the arterial wall adjacent to the aneurysm seems to have been the cause of the formation of a new aneurysm. The need to reinforce the thin‐walled parent artery and the usefulness of high resolution computed tomography for the early detection of recurrent aneurysms are emphasized. (Neurosurgery11:764‐768, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Cerebrospinal fluid (CSF) pressure and absorption were determined in 12 patients with benign noncommunicating hydrocephalus. An extracorporeal communication of plastic tubing between the ventricular system and the lumbar subarachnoid space was established to imitate the hydromechanical condition after an intracranial bypass operation. This extracorporeal shunt, which in effect was an externalized Torkildsen shunt, served first as a test shunt for 1 hour and then as a route for the constant rate CSF infusion test. The total CSF absorptive capacity was thus determined under a condition of balanced CSF pressure between the proximal and distal compartment. Four patients, whose tests showed normal CSF pressure and absorption, were selected for intracranial bypass operation. Follow‐up examination showed a normal clinical condition, reduction of the ventricular system, normal CSF pressure, and normal CSF absorption in all 4 patients. The other 8 patients, whose tests indicated impaired CSF absorption, were treated by ventriculoatrial shunting. The tests were valid in selecting patients for intracranial bypass operation. (Neurosurgery11:769‐775, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Spontaneous regression of an arteriovenous malformation (AVM) is quite rare. When a regression does occur, there is usually an associated factor, such as intracranial hemorrhage, operation, radiation therapy, or new neurological deficit. Twenty‐one cases of AVM regression identified in the literature are reviewed. An additional case in which the resolution was totally spontaneous is presented. Regressions occurred over intervals ranging from 7 months to 21 years. Several mechanisms for regression are discussed. (Neurosurgery11:776‐780, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Eight of 48 patients with shunt infections were treated with antibiotic therapy only. Seven of the 8 were cured and remained infection‐free for at least 1 year. Six of the 7 patients had developed infection within 2 weeks of shunt insertion or revision. Shunt infections that occur soon after operation may have a good cure rate with antibiotics and no surgical intervention. (Neurosurgery11:781‐783, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;Postsurgical discomfort after lumbar discectomy can be minimized substantially by following a paramedian approach to the disc through a small incision. Comparison of results after this procedure and after a microsurgical approach showed a similar benign postoperative course. (Neurosurgery11:784‐785, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID

摘要:

&NA;A newly designed cottonoid is fixed to the tip of the suction device by the negative pressure. It is especially useful during microsurgical procedures in areas crowded with neurovascular elements. The advantage of pressure‐mounted cottonoids lies in the protection provided to the brain and neurovascular elements during suction, even in the face of high aspiration pressure, and in the simplicity of their use. (Neurosurgery11:786, 1982)

ISSN:0148-396X    

出版商:OVID    

年代:1982

数据来源: OVID