摘要:

&NA;In most standard anatomical textbooks, the cavernous branches of the internal carotid artery (ICA) are rarely or shortly described. Among three reports dealing with these branches, there is a lack of agreement in description and nomenclature. This study presents a systematic nomenclature based on the result of anatomical dissection in the cavernous sinus (CS) of 32 human subjects. The ophthalmic artery was found arising inside the CS in 5 subjects (15.6%). The posterior trunk (meningohypophyseal trunk of Parkinson) was present in all subjects (100%), but its distribution varied considerably. In 9 subjects, one or two of its primary divisions originated directly from the ICA. The lateral trunk was found in 21 subjects (65.8%), and the capsular arteries of McConnell of the median group were found in 9 (28.1%). Other branches to the surrounding structures (trigeminal ganglion and divisions, superior wall of the CS, the 3rd, 4th, and 6th cranial nerves, and osseous branches) were inconstant. Anastomotic branches to the ophthalmic, middle meningeal, and ascending pharyngeal arteries were also noted. A systematic nomenclature is proposed, in which the branches of the ICA are named according to their topographical origins from the artery and their primary or secondary divisions are named according to their destinations. (Neurosurgery20:205‐210, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;The auditory evoked response (AER) was used to study the effect of increased intracranial pressure (ICP) on the auditory pathway in normal New Zealand rabbits and in those made hydrocephalic by intracisternal injections of kaolin. AERs were studied: (a) in the normal and then in the hydrocephalic animal; and (b) in the hydrocephalic animal during further ICP elevation by cerebrospinal fluid infusion. The AER was obtained from ongoing electroencephalographic activity after rarefaction auditory clicks presented at 90 dB sound pressure equivalent. In comparing base line normal AERs to those found in hydrocephalic conditions, a statistically significant increase in latency for AER components N2, P2, and P5was noted in hydrocephalic rabbits. Increased ICP in the hydrocephalic model showed an increase in the latencies of AER components for P0and P1at 250 mm H2O, and a prolongation of P3‐P5central conduction time at 700 mm H2O above base line cerebrospinal fluid pressure. In addition, a decrease in the P4/N5amplitude and an increase in P1‐P3central conduction times at 700 mm H2O was observed. The differences between normal and hydrocephalic rabbit AER base lines may be the result of the chronically increased ICP and presumed chronic anatomical changes within the auditory pathway due to kaolin itself. The differences in the AER from base line hydrocephalus to acute increased ICP may indicate that the hydrocephalic system is more sensitive to acute neuropraxic pressure effects on the brain stem auditory structures than is the normal brain. (Neurosurgery20:211‐218, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;Experimental carbon dioxide brain lesions were created over the intact dura mater of the left parietooccipital region of the anesthetized albino rabbit (40‐watt impacts of 0.5‐second duration, for a total of 4 seconds, with 0.5‐second intervals between impacts), and cerebral blood flow (CBF) studies were performed with the hydrogen clearance technique. The animals were mechanically ventilated to maintain a constant PaCO2. Blood pressure, central venous pressure, electroencephalogram, and intracranial pressure were continuously monitored. The control CBF before lesion was 64.1 ± 15.8 and 70.9 ± 13.4 ml/100 g/minute for the left and the right hemispheres, respectively. CBF studies at 2, 4, 6, 8, and 24 hours after the lesion did not significantly change from the control values, save for a trend to increase over the right hemisphere only at 2 hours (range 106.0 ± 55.4 to 41.6 ± 9.3). It is concluded that in this model the changes in intracranial pressure and brain edema that are seen and have been previously reported are not due to change in cerebral circulation. The brain edema that results probably has characteristics similar to those seen in the cryogenic lesion (vasogenic) model, and this could account for the rise in intracranial pressure. (Neurosurgery20:219‐221, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;With the advent of magnetic resonance imaging (MRI) of the brain, a large number of incidental lesions (ILs) are being identified. The prevalence and clinical significance of these ILs are not known. The MRI and clinical records of 86 consecutive patients who underwent technically satisfactory brain imaging at a large urban referral center were reviewed. Patients with definite or probable demyelinating disease were excluded. Incidental lesions were defined as parenchymal areas of increased signal intensity on T2‐weighted imaging, which could not be directly explained by the patient's current clinical diagnosis, neurological status, or computed tomographic (CT) scan. The ILs were noted and graded according to size, multiplicity, and location and were correlated with age, clinical presentation, CT scan findings, and risk factors for cerebrovascular disease. One or more IL were identified in 22% of patients under 40 years of age, in 57% of patients 41 to 60 years of age, and in 90% of patients over 60 years of age. Large patches of confluent ILs were not encountered in any patient less than 40 years of age; they were present in 10% of patients 41 to 60 years of age, and in 30% of patients over 60 years of age. The incidence of severity of ILs correlated significantly with age (P< 0.0005) and with risk factors for cerebrovascular disease (P< 0.02). Patients with most severe ILs also had areas of vague periventricular leukomalacia on the CT scan. The clinical significance of incidental MRI lesions in various age groups is discussed in detail. It is concluded that deep hemispheric lesions are frequent incidental findings on MRI in the elderly, and may represent an index of chronic cerebrovascular disease in these patients. (Neurosurgery20:222‐227, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;Fifty unfixed cerebral hemispheres were injected with polyester resin and dissected under the operating microscope to show the anatomy of the posterior communicating artery (PCoA). There was a single PCoA in every hemisphere. Eleven (22%) were of fetal origin, and 17 (34%) were hypoplastic. Infundibular dilatations were found in 5 (10%) of the arteries. The outer diameter (OD) of the PCoA at its origin was 1.5 ± 0.8 mm on the right and 1.6 ± 0.6 mm on the left. At the junction of the PCoA with the P1segment of the posterior cerebral artery, the PCoA had an OD of 1.4 ± 0.7 mm on the right side and 1.6 ± 0.6 mm on the left. The total length of the PCoA was 12.7 ± 3.2 mm on the right and 12.5 ± 1.7 mm on the left side. PCoA branches originated from the superior (36%) or lateral (64%) surface of the PCoA and coursed superiorly, posteriorly, or laterally. These vessels supplied the paramedian perforated substance (21%), the tuber cinereum (16.8%), the sulcus between the optic tract and the tuber cinereum (14.4%), the circuminfundibular anastomosis (11.5%), the mamillary bodies (8.4%), the sulcus between the optic tract and the cerebral peduncles (7.6%), and the cerebral peduncles (5.7%). The largest and most constant branch of the PCoA was the premamillary artery. The number and size of the branches from the PCoA were independent of the size of the parent artery. (Neurosurgery20:228‐235, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;The occurrence of intracranial aneurysms (IAs) in the families of 579 consecutive patients with subarachnoid hemorrhage (SAH), of whom 485 had verified IAs, was studied retrospectively. IAs occurred in the families of 6.7% of the IA patients, but only 0.4% of their siblings had IAs. However, there were differences between the familial and nonfamilial IA patients, indicating that the familial patients are a specific small subpopulation of IA patients. The familial patients were younger, often had multiple aneurysms, and had aneurysms frequently located on arteries other than those in the nonfamilial group. (Neurosurgery20:236‐239, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;These experiments were done to develop techniques to expose and manipulate the spinal cord in fetal rats, techniques that could be used to study spinal cord regeneration and transplantation. Adequate maternal anesthesia required a mixture of acepromazine‐ketamine supplemented by thiopental. Fetal rats were operated on at 16 to 22 days of gestation. Fetal mortality increased as the age of the fetus decreased. Microsurgical techniques were developed to expose, divide, and transplant the distal spinal cord. (Neurosurgery20:240‐242, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;The distribution of cholesterol in the astrocytic plasma membranes of normal and ischemic caudate nucleus in the cat was investigated with the polyene antibiotic, filipin, a morphological probe for membrane cholesterol domains in freezefracture tissue replicas. After filipin incubation of prefixed vibratome slices, filipin‐cholesterol complexes appeared as 20 to 30 nm protuberances and pits on P‐ and E‐faces of the replicas. Distinct patterns of filipin‐cholesterol complexes were found on nonischemic and ischemic astrocyte membranes. The filipin‐treated specimens showed an 80% decrease in astroglial plasmalemma of cholesterol 1 hour after cerebral ischemia. (Neurosurgery20:243‐248, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;In some cases, basilar artery aneurysms cannot be repaired surgically and the basilar artery is occluded near the neck of the aneurysm to stop flow into the aneurysm. After the operation, the aneurysm can fill only by flow through the posterior communicating arteries (PCoAs). Hemodynamically, if the flow were the same in both PCoAs and there were no phase lag in the pressures, there would be no pressure gradient for flow to go across the neck of the aneurysm and therefore the aneurysm would thrombose. We have assumed that the diameter of the artery is roughly proportional to the flow that goes through it chronically. We measured the diameters of the PCoAs in 25 patients who had hunterian ligation of the basilar artery. We also measured the maximal width, height, and depth of the aneurysms on angiograms obtained before and after operation. Eleven aneurysms thrombosed completely and had a diameter ratio of >0.6; 10 aneurysms thrombosed partially and had a diameter ratio of 0.46 ˜ 1.0; 4 aneurysms did not change and had a diameter ratio of <0.45. The ratio of the sizes of the PCoAs pre‐ and postoperatively was comparable in most cases, so we believe that it is possible to predict reasonably accurately from this simple measurement whether the aneurysm is likely to thrombose if the basilar artery is ligated. (Neurosurgery20:249‐253, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID

摘要:

&NA;Seventy‐six patients with closed head injuries alone were studied to define the relation between the severity of the head injury and secondary alterations of general metabolism. The effect of metabolic changes on neurological outcome and the importance of nutritional support on nutritional status and neurological outcome were also evaluated. Using a powerful statistical tool, convergence analysis, it was possible to take into consideration the effects of a number of confounding factors that obviously affected general metabolism. Most of the patients were hypermetabolic for prolonged periods. In addition, many did not receive even basal requirements of calories or protein for many days. Despite this, their outcomes were determined by their initial neurological status and the amounts that they were fed, admittedly relatively modest, did not influence their courses. Despite such feedings, their visceral protein levels, which often dropped initially, rose toward normal levels, indicating effective adaptation. Indeed, it could not be shown that these patients developed complications of malnutrition such as infections. However, it will require a sophisticated randomized clinical trial of vigorous intravenous hyperalimentation to determine whether this complex, dangerous, and expensive therapy is helpful for severely head‐injured patients. (Neurosurgery20:254‐265, 1987)

ISSN:0148-396X    

出版商:OVID    

年代:1987

数据来源: OVID