Abstract:
OBJECT:The angles of arterial bifurcations are governed by principles of work minimization (optimality principle). This determines the relationship between the angle of a bifurcation and the radii of the vessels. Nevertheless, the model is predicated on an absence of significant communication between these branches. The circle of Willis changes this relationship because the vessels proximal to the ring of vessels have additional factors that determine work minimization compared with more distal branches. This must have an impact on understanding of the relationship between shear stress and aneurysm formation. The authors hypothesized that normal bifurcations of cerebral arteries beyond the circle of Willis would follow optimality principles of minimum work and that the presence of aneurysms would be associated with deviations from optimum bifurcation geometry. Nevertheless, the vessels participating in (or immediately proximal to) the circle of Willis may not follow the geometric model as it is generally applied and this must also be investigated. METHODS:One hundred seven bifurcations of the middle cerebral artery (MCA), distal internal carotid artery (ICA), and basilar artery (BA) were studied in 55 patients. The authors analyzed three-dimensional reconstructions of digital subtraction angiography images with respect to vessel radii and bifurcation angles. The junction exponent (that is, a calculated measure of the division of flow at the bifurcation) and the difference between the predicted optimal and observed branch angles were used as measures of deviation from the geometry thought best to minimize work. The mean junction exponent for MCA bifurcations was 2.9 +/- 1.2 (mean +/- standard deviation [SD]), which is close to the theoretical optimum of 3, but it was significantly smaller (p < 0.001; 1.7 +/- 0.8, mean +/- SD) for distal ICA bifurcations. In a multilevel multivariate logistic regression analysis, only the observed branch angles were significant independent predictors for the presence of an aneurysm. The odds ratio (OR) (95% confidence interval) for the presence of an aneurysm was 3.46 (1.02-11.74) between the lowest and highest tertile of the observed angle between the parent vessel and the largest branch. The corresponding OR for the smallest branch was 48.06 (9.7-238.2). CONCLUSIONS:The bifurcation beyond the circle of Willis (that is, the MCA) closely approximated optimality principles, whereas the bifurcations within the circle of Willis (that is, the distal ICA and BA) did not. This indicates that the confluence of hemodynamic forces plays an important role in the distribution of work at bifurcations within the circle of Willis. In addition, the observed branch angles were predictors for the presence of aneurysms.
journal_name
J Neurosurgjournal_title
Journal of neurosurgeryauthors
Ingebrigtsen T,Morgan MK,Faulder K,Ingebrigtsen L,Sparr T,Schirmer Hdoi
10.3171/jns.2004.101.1.0108subject
Has Abstractpub_date
2004-07-01 00:00:00pages
108-13issue
1eissn
0022-3085issn
1933-0693journal_volume
101pub_type
杂志文章abstract::Dolichoectatic and fusiform aneurysms represent a small subset of cerebral aneurysms and are often among the most difficult to treat. A consecutive series of 40 patients with 41 of these two types of aneurysms is presented, including their clinical characteristics and surgical treatments. Common to all aneurysms was t...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1996.84.2.0185
更新日期:1996-02-01 00:00:00
abstract::The case of General Leonard Wood is notable both for its contribution to the field of neurosurgery and its historical significance. As one of Harvey Cushing's first successful brain tumor operations in 1910, Wood's surgery was part of the case series that culminated in Cushing's monograph Meningioma. This case was imp...
journal_title:Journal of neurosurgery
pub_type: 传,历史文章,杂志文章
doi:10.3171/2011.7.JNS102067
更新日期:2011-12-01 00:00:00
abstract:OBJECTIVE:Stereotactic radiosurgery (SRS) is a commonly employed treatment modality for brain arteriovenous malformations (AVMs). However, due to the low frequency of delayed cyst formation after AVM SRS, as well as the prolonged time interval between treatment and its occurrence, the characteristics of post-SRS cyst f...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/2017.6.JNS17559
更新日期:2018-10-01 00:00:00
abstract::The radiographic features and long-term clinical outcome in three patients who presented at birth with a cystic suboccipital mass in direct communication with the fourth ventricle are reviewed. The pathological findings in a fourth infant who died are also discussed. All surviving infants were treated with cyst excisi...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1984.61.2.0348
更新日期:1984-08-01 00:00:00
abstract::OBJECTIVE Hemangiopericytomas (HPCs) are rare tumors widely recognized for their aggressive clinical behavior, high recurrence rates, and distant and extracranial metastases even after a gross-total resection. The authors report a large multicenter study, through the International Gamma Knife Research Foundation (IGKR...
journal_title:Journal of neurosurgery
pub_type: 杂志文章,多中心研究
doi:10.3171/2016.1.JNS152860
更新日期:2017-03-01 00:00:00
abstract::A 48-year-old laborer presented with a 1-year history of low-back pain radiating into the posterior aspects of both thighs. Two weeks before admission, acute exacerbation resulted in signs and symptoms of compressive radiculopathy at L-5. Myelography revealed concentric constriction of the lower thecal sac due to abun...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1982.57.4.0559
更新日期:1982-10-01 00:00:00
abstract::The authors report a case of neurofibromatosis Type 2 presenting with symptoms of trigeminal neuralgia refractory to medical management following placement of an auditory brainstem implant (ABI). Physical examination and history revealed trigeminal neuralgia. A 3D FIESTA (fast imaging employing steady-state acquisitio...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/2010.5.JNS091709
更新日期:2011-01-01 00:00:00
abstract::Mannitol is widely considered the hyperosmolar therapy of choice in routine neurosurgical practice for the reduction of intracranial pressure (ICP). The authors present a unique case of a patient with a large meningioma treated with mannitol, in which mannitol accumulation within the tumor and its surrounding parenchy...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/JNS/2008/108/5/1010
更新日期:2008-05-01 00:00:00
abstract::Levels of protein kinase C (PKC) isoforms in eight human glioblastoma cell lines and two normal human glial cell cultures were determined. Earlier studies identified PKC-alpha and PKC-gamma in these cell lines but PKC-beta was not present. In this study, PKC-epsilon and PKC-zeta are demonstrated immunologically in the...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1994.81.5.0734
更新日期:1994-11-01 00:00:00
abstract::Intraventricular rupture of a colloid cyst is a rare phenomenon and has been proposed as a mechanism for sudden death in patients with colloid cysts. Imaging of a colloid cyst during rupture has been described in only one other instance. The authors report a highly unusual case of a 53-year-old man who presented with ...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/2016.5.JNS153015
更新日期:2017-06-01 00:00:00
abstract::A 30-year-old man presented with a subacute course of myelopathic signs and symptoms. Magnetic resonance imaging demonstrated an epidural mass lesion of the spinal canal at the cervicothoracic junction causing compression of the spinal cord. Laminectomy with resection of this lesion revealed a large varix with acute a...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1988.69.6.0940
更新日期:1988-12-01 00:00:00
abstract:OBJECT:Sellar lesions with suprasellar extension may cause loss of visual acuity and visual field damage due to compression of the optic chiasm. Using intraoperative MR (iMR) imaging to detect symptomatic lesion remnants adjacent to the optic chiasm (that may be resected in the same procedure) may positively affect the...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/2011.4.JNS101568
更新日期:2011-09-01 00:00:00
abstract::Bacteriological studies were performed on 45 craniocerebral missile wounds incurred in Vietnam within 2 to 4 hours of occurrence. All missiles had penetrated into the brain. Aerobic and anaerobic cultures were taken of the skin wound, brain, and indriven bone fragments. Forty-four of the skin wounds were contaminated,...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1971.34.2part1.0145
更新日期:1971-02-01 00:00:00
abstract::The problems of sickle cell disease and its complications is discussed. Subarachnoid hemorrhage is not a common complication of sickle cell disease and should be evaluated in the same way as if it were not associated with the disease. Patients with sickle cell trait have an added risk during angiography and hypotensiv...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1977.47.5.0761
更新日期:1977-11-01 00:00:00
abstract:OBJECT:The use of nicardipine prolonged-release implants (NPRIs) is associated with a significant improvement in the therapy of patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) regarding the occurrence and severity of cerebral vasospasm, new infarcts, and functional outcome (FO). Because quality of lif...
journal_title:Journal of neurosurgery
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.3171/2008.2.17670
更新日期:2009-05-01 00:00:00
abstract::The authors report on an unusual case of a primary intracranial myxoma in a 39-year-old woman. The patient presented with headache and generalized seizure. Magnetic resonance imaging revealed a large right frontal tumor resembling a parasagittal meningioma. A gross-total resection was performed, and histological revie...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.2006.104.3.440
更新日期:2006-03-01 00:00:00
abstract::The lateral extracavitary approach to the spine was used for resection of displaced bpne and disc located anterior to the dura in 62 patients with traumatic lesions of the thoracic and lumbar spine. Fifty-two patients had closed vertebral fractures and 10 had gunshot wounds. The spinal cord was involved in 44 patients...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1976.45.6.0628
更新日期:1976-12-01 00:00:00
abstract::The authors report their investigation of the effects of high-dose barbiturates on the multimodality evoked response in 9 cats. After baseline evoked responses were obtained, boluses of pentobarbital were infused intravenously at regular intervals, amounting to cumulative total doses of 9, 18, 27, 45, 63, 123, and 183...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1982.57.2.0178
更新日期:1982-08-01 00:00:00
abstract::OBJECTIVEDecompressive craniectomy is used for uncontrolled intracranial pressure in traumatic brain injury and malignant hemispheric stroke. Subcutaneous preservation of the autologous bone flap in the abdomen is a simple, portable technique but has largely been abandoned due to perceived concerns of resorption. The ...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/2017.6.JNS17943
更新日期:2018-12-01 00:00:00
abstract:OBJECT:Microangiopathy associated with hypertension is a notable cause of cerebral small vessel disease (SVD), including deep intracerebral hemorrhage (ICH) and lacunar infarct. Dotlike low-intensity spots (dotlike hemosiderin spots: dotHSs) on T2*-weighted magnetic resonance (MR) images have been histologically diagno...
journal_title:Journal of neurosurgery
pub_type: 临床试验,杂志文章
doi:10.3171/jns.2004.101.6.0915
更新日期:2004-12-01 00:00:00
abstract:OBJECT:Telomerase activity is responsible for cell immortality. To examine the role of telomerase in the carcinogenesis of human glioblastomas multiforme (GBMs), the authors studied telomerase activity, telomerase component expression, and telomere lengths in 42 GBM samples. METHODS:In all samples, EGFR and MDM2 ampli...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.2000.93.4.0618
更新日期:2000-10-01 00:00:00
abstract::Cranial and spinal trauma resulted in disseminated intravascular coagulation (DIC) in a 78-year-old man, causing widespread bleeding and incoagulable blood. Traumatized brain tissue was found in the lumina of dural venous sinuses. The mechanisms of DIC are reviewed. It is suggested that intravascular release of potent...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1980.52.2.0266
更新日期:1980-02-01 00:00:00
abstract::In clinical follow-up studies after radiosurgery, imaging modalities such as computerized tomography (CT) and magnetic resonance (MR) imaging are used. Accurate determination of the residual lesion volume is necessary for realistic assessment of the effects of treatment. Usually, the diameters rather than the volume o...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.2000.93.supplement
更新日期:2000-12-01 00:00:00
abstract::The roles of hemoglobin (Hb) in the pathogenesis of cerebral vasospasm remain a matter of discussion. Hemoglobin is known to be released from extravasated red blood cells in a variety of pathological conditions, including subarachnoid hemorrhage. These conditions are often accompanied by infiltration of inflammatory c...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1994.81.6.0895
更新日期:1994-12-01 00:00:00
abstract::Optochiasmal arachnoiditis has been reported following treatment of ruptured intracranial aneurysms, particularly arising from the anterior communicating artery. It has been suggested that the accompanying loss of vision is due to a muslin-induced optic neuropathy. This paper considers five cases of this condition; th...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1991.75.3.0393
更新日期:1991-09-01 00:00:00
abstract::A method of lateral orbital rim advancement is described for periorbital deformities associated with coronal and metopic synostosis in infants. The technique offers the advantages of a smooth lateral rim contour and improvement in accompanying malar recession. In 13 patients with follow-up periods of up to 2 years fol...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1990.72.1.0022
更新日期:1990-01-01 00:00:00
abstract::Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5-year period (1989-1993) at a single institution. Major primary s...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1996.85.3.0438
更新日期:1996-09-01 00:00:00
abstract:OBJECT:The management of massive brain swelling remains an unsolved problem in neurosurgery. Despite newly developed medical and pharmacological therapy, the rates of mortality and morbidity caused by massive brain swelling remain high. According to many recent reports, surgical decompression with dural expansion is su...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1999.91.6.0953
更新日期:1999-12-01 00:00:00
abstract::In this experiment, the effects of ischemia on neural conduction in the monkey spinal cord were studied. In six monkeys generalized ischemia of the spinal cord was created by bleeding the animals to a hypotensive level below the lower limits of autoregulation in the spinal cord. The progressive development of spinal c...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/jns.1979.50.5.0639
更新日期:1979-05-01 00:00:00
abstract:OBJECT:The authors analyzed the role of endoscopic third ventriculostomy (ETV) as a primary treatment for hydrocephalus and also as an alternative to shunt revision for malfunctioning and infected ventriculoperitoneal (VP) shunts. METHODS:A retrospective analysis of clinical notes, operation records, and magnetic reso...
journal_title:Journal of neurosurgery
pub_type: 杂志文章
doi:10.3171/ped.2005.103.5.0393
更新日期:2005-11-01 00:00:00