摘要:

&NA;The surgical approaches to the cavernous sinus were examined in 50 adult cadaveric cavernous sinuses using magnification of х3 to х40. The following approaches were examined:1) the superior intradural approach directed through a frontotemporal craniotomy and the roof of the cavernous sinus:2) the superior intradural approach combined with an extradural approach for removing the anterior clinoid process and unroofing the optic canal and orbit;3) the superomedial approach directed through a supraorbital craniotomy and subfrontal exposure to the wall of the sinus adjacent to the pituitary gland;4) the lateral intradural approach directed below the temporal lobe to the lateral wall of the sinus;5) the lateral extradural approach for exposure of the internal carotid artery in the floor of the middle cranial fossa proximal to the sinus;6) the combined lateral and inferolateral approach, in which the infratemporal fossa was opened and the full course of the petrous carotid artery and the lateral wall of the sinus were exposed and;7) the inferomedial approach, in which the medial wall of the sinus was exposed by the transnasal‐transsphenoidal route. It was clear that a single approach was not capable of providing access to all parts of the sinus. The intracavernous structures best exposed by each route are reviewed. The osseous relationships in the region were examined in dry skulls. Anatomic variants important in exposing the cavernous sinus are reviewed. (Neurosurgery26:903‐932, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Of 37 patients with 44 intracavernous carotid artery aneurysms (ICCAAns) diagnosed between 1976 and 1988. patients with 20 aneurysms were followed without treatment for 5 months to 13 years (median, 2.4 years). Ten of the 20 ICCAAns were asymptomatic at diagnosis, and 10 were symptomatic. Three of the asymptomatic ICCAAns were symptomatic at follow‐up. One of these required clipping because of a progressing cavernous sinus syndrome; the other 2 were minimally symptomatic and have not required treatment. Of the 10 initially symptomatic ICCAAns, 2 had not changed, 4 became more symptomatic, and 4 had symptomatically improved by follow‐up. One patient with an ICCAAn that had not changed clinically was lost to follow‐up 6 months after diagnosis. Of the 4 ICCAAns that became more symptomatic, 2 continue to be monitored, and 2 required intervention; one with detachable balloon occlusion of the aneurysm with preservation of the internal carotid artery lumen, and the other with gradual cervical internal carotid artery occlusion. The clinical course of this selected group of patients with ICCAAns suggests that the natural history of ICCAAns can be quite variable. Although clinical progression does occur, symptomatic ICCAAns also can improve spontaneously. Therapeutic intervention for asymptomatic ICCAAns should be reserved for patients with aneurysms arising at the anterior genu of the carotid siphon and/or extending into the subarachnoid space, where subarachnoid hemorrhage is most likely. Intervention for symptomatic ICCAAns should be reserved for patients with subarachnoid hemorrhage, epistaxis, severe facial or orbital pain, evidence of radiographic enlargement, progressive ophthalmoplegia, or progressive visual loss. (Neurosurgery26:933‐938, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Elastin and reticular fibers were identified using standard histological stains in middle cerebral arteries taken from patients who had died from aneurysmal subarachnoid hemorrhage and control patients who did not have cerebral aneurysms, Examination of cerebral arteries from normal individuals revealed a dense network of fine reticular fibers in the arterial media that were uniformly distributed. Computerized morphometric analysis indicated that reticular fibers in the arterial media of cerebral arteries were significantly decreased in patients with aneurysms. In addition, these fibers were irregularly distributed and shortened when compared to those seen in control arteries. In both patients with aneurysms and control patients, elastin fibers were limited almost exclusively to the internal elastin lamina. No differences were observed in the appearance or content of elastin fibers in control patients and patients with aneurysm. Although other explanations cannot be excluded, these observations are consistent with the hypothesis that “intrinsic“ abnormalities in the walls of cerebral arteries lead to conditions that favor the formation and rupture of cerebral aneurysms. (Neurosurgery26:939‐943, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Clinical evidence suggests that a moiety of patients with low back syndrome refractory to conventional treatment may embody a pleiotropic expression of Marfan‐like pathology of support tissue. Individuals in the suspect group display a triad of clinical findings including refractory low back syndrome, certain dural ectasias, and a susceptibility to protracted reactions after lumbar puncture. Certain stigmata found in these patients and their families are among those commonly seen in Marfan's disease. The concept, if valid, has important implications affecting therapeutic choices and may offer insights into unexplained failures. The finding of significant family involvement strengthens the possibility of a heritable substratum for this category of low back disease. (Neurosurgery26:944‐951, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Spinal cord blood flow (SCBF) and motor performance on the inclined plane were measured up to 9 days after a reversible spinal cord compression injury in 49 Sprague‐Dawley rats. A load of 35 g on 11 mm2of the thoracic spinal cord for 5 minutes caused transient paraparesis with a decrease in the capacity angle on the inclined plane from 62± 1° (mean ± SEM) before injury to 33 ± 1° on Day 1, 45 ± 2° on Day 4, and 54 ± 3° on Day 9. SCBF was measured by the [14C] iodoantipyrine method, and in gray matter there was a decrease from 78.4 ± 2.3 ml/min/100 g of tissue in uninjured animals to 33.7 ± 1.5 ml/min/100 g of tissue on Day 1 after injury, increasing to 50.1 ± 2.0 on Day 4 and to 70.5 ± 2.7 ml/min/100 g of tissue on Day 9. At the corresponding times, the SCBF values in white matter were 14.5 ± 0.5, 6.7 ± 0.5. 10.2 ± 0.6, and 13.4 ± 0.6 ml/min/100 g of tissue, respectively. The animals in another group were loaded with 25 g for 5 minutes and on Day 1 exhibited a capacity angle of 43 ± 2° while the SCBF values for gray and white matter were 55.1 ± 2.0 and 11.1 ± 0.4 ml/min/100 g of tissue, respectively; thus, the results in this group were similar to the values on Day 4 in the animals loaded with 35 g. There was a significant linear correlation between SCBF in both gray and white matter, on the one hand, and the capacity angle on the other. This suggests that in this model, the disturbance in SCBF after spinal cord injury is related to the motor deficit in spinal cord function. (Neurosurgery26:952‐957, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;We used the tissue distribution of [14C]butanol to quantitate regional blood flow in the spinal cord (RSCBF) of pentobarbital‐anesthetized. normothermic rats in which segmental local cooling of the spinal cord (to 25‐28°C) at vertebral levels C4‐C6 (n = 6) was induced. Thirty minutes later, blood flow measurements were made at seven levels of the spinal cord and in the sciatic nerve trunks and biceps femoris muscles. Sham‐cooled rats served as controls (n = 12). In control rats. RSCBF varied between 41.5 ± 2.4 and 65.1 ± 3.2 ml ‐ min‐1‐. 100 g‐1. Local cooling of the C4‐C6 cord segment reduced RSCBF by 32%, from 65.1 ± 3.2 to 44.4 ± 3.5 ml ‐ min1‐ 100g‐1(P<0.01). Tissue vascular resistance (R) in the cooled C4‐C6 segment was elevated versus control. There were no other changes in RSCBF at the other cord levels or in the cauda equina. Similarly, local cooling of the T13‐L1 segment resulted in a 40% fall in RSCBF in that segment, from 57.1 ± 2.4 to 34.1 ± 4.3 ml ‐ min‐1‐ 100g‐1(P<0.001). R in the cooled T13‐L1 segment was elevated versus control. RSCBF was reduced by 30% in the adjacent proximal T12 segment (P<0.001) and by 21% in the adjacent distal L2‐L3 segment (P<0.05). R was increased in both of these adjacent segments. RSCBF was not altered elsewhere in the cord. There were no differences among test and control rats in mean arterial blood pressure, arterial blood gases, or anesthetic duration. We conclude that local cooling of the spinal cord in pentobarbital‐anesthetized rats reduces RSCBF in the cooled (and adjacent) segments, but not at other levels of the spinal cord. (Neurosurgery26:958‐962, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Excitotoxin‐induced neural tissue damage is mediated through specific receptors. We studied the in vivo effect of two selectiveN‐methyl‐D‐aspartate receptor antagonists on the compressed spinal cord segments of rats harboring a thoracolumbar epidural tumor. The effect of a single intramuscular treatment with either MK‐801 (3 mg/kg) or ketamine (110 mg/kg) given at the onset of paraplegia was evaluated 30 hours later. In saline‐treated control animals. significant increases in water content, prostaglandin E2, and 6‐keto‐prostaglandin F1&agr;were evident. Treatment with either agent resulted in a normal water content in the compressed segments but had no effect on prostaglandin synthesis. Evaluation of the effect of treatment on the course of the disease required dose reduction by 45% for ketamine and by 30% for MK‐801, to avoid the excessive sedative effect. Treatment was started at the first appearance of neurological dysfunction (Grade 1) and continued to paraplegia (Grade 5). The mean time interval between Grades 1 and 5 was 2.1 ± 0.3 days in saline‐treated control animals, and it was not significantly altered by either ketamine or MK‐801. Our study indicates that in the end stage of epidural compression, when ischemia is present, excitotoxins probably participate in the evolution of a cytotoxic edema. It is suggested that treatment initiated at the onset of paraplegia may still reduce the cytotoxic edema, but its potential clinical value requires further investigations. (Neurosurgery26:963‐966, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;It has been demonstrated in paraplegic rats harboring an epidural neoplasm that an antiedema effect can be achieved by in vivo treatment with either steroidal or nonsteroidal anti‐inflammatory agents or by glutamate receptor antagonists. The effect of these treatments on vascular permeability of the normal and compressed spinal cord was quantitated by the Evans blue dye technique. Tumor‐free and tumor‐bearing rats were assigned randomly for treatment as follows: 0.5 ml of saline or three doses at 12‐hour intervals of either dexamethasone (5 mg/kg), methylprednisolone (30 mg/kg), indomethacin (5 mg/kg every 24 hours), or a single dose of either ketamine (110 mg/kg) or MK‐801 (3 mg/kg). Treatment was given at the onset of paraplegia, and the animals were killed after 30 hours. In tumor‐bearing rats in the early symptomatic stage, extravasation of Evans blue dye was 4.8 times greater than that of the normal cord (P<0.001) and at the onset of paraplegia it was 9.9 times greater (P<0.0006), Glucocorticoids and indomethacin reduced dye extravasation in paraplegic animals (P<0.01 andP<0.003, respectively), but the decreased permeability induced by ketamine and MK‐801 did not reach the level of significance. In tumor‐free control animals permeability was not changed by administration of either glucocorticoids or indomethacin but was significantly reduced by ketamine or MK‐801 801 (P<0.01). It is suggested that the disparity in the effect on vascular permeability between the anti‐inflammatory agents and glutamate receptor antagonists in the normal and the pathological states offers further support to the concept that spinal cord edema in epidural compression is probably related to both vasogenic and cytotoxic edema. (Neurosurgery26:967‐970, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;Positron emission tomography is currently one of the most useful methods for measurements of cerebral hemodynamics and oxygen metabolism, because it facilitates accurate analysis of the local cerebral circulation in three‐dimensional quantitative images. In this study, we performed positron emission tomography studies to measure cerebral circulation in a total of 11 patients who sustained head injuries with contusion. Several parameters were measured including regional cerebral blood flow, regional cerebral blood volume, permeability, and regional cerebral metabolic rate for oxygen. Data from brains both with and without contusion were analyzed for chronological changes, in the subacute stage from the 8th to 29th day and in the chronic stage until 360 days after the injury and compared with similar data in a group of normal subjects. It was concluded that in the subacute stage, regional cerebral blood flow decreased (26 ± 7 and 39 ± 10 ml/100 g/min) and regional cerebral blood volume increased (5.6 ± 1.8 and 5.4 ± 0.9 ml/100 g) both in areas of cerebral contusion and in areas remote from cerebral contusion and that permeability increased in areas of contusion but not in remote brain areas. In the chronic stage, these parameters showed a tendency for recovery. (Neurosurgery26:971‐979, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID

摘要:

&NA;A retrospective review of 16 consecutive patients with pituitary apoplexy treated over a 10‐year period is reported. Eight men and 8 women (mean age, 48 years) underwent transsphenoidal decompression after an average duration of symptoms of 19 days. The diagnosis of pituitary apoplexy was made by the sudden onset of headache (88%), nausea (56%), or meningismus (13%), with or without visual disturbances (75%), in the setting of a sellar tumor on computed tomographic or magnetic resonance imaging scans. Thirteen of 16 patients showed significant improvement of symptoms after surgery (average follow‐up, 2.5 years). In addition, 5 patients with clinically silent yet extensive pituitary hemorrhage were treated. Although extensive pituitary hemorrhage often produced fulminant apoplexy, it also presented insidiously over many days with few, if any, clinical signs. Rapid diagnosis, endocrine replacement, and transsphenoidal decompression constituted effective therapy. Magnetic resonance imaging (after at least 12 hours of symptoms) was superior to computed tomography in detecting hemorrhage. (Neurosurgery26:980‐986, 1990)

ISSN:0148-396X    

出版商:OVID    

年代:1990

数据来源: OVID