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81.
目的探讨B超及多排螺旋CT血管造影(CTA)在诊断颈动脉海绵窦瘘中的应用价值。方法分析23例颈动脉海绵窦瘘病例。对受检者行B型超声及颅脑CTA检查,采用容积再现(VR)、最大密度投影(MIP)、多平面重建(MPR)技术处理图像。结果超声可发现增粗的眼上静脉与脉搏同步搏动,并能检测血流频谱,CT检查发现23例均海绵窦扩大.动脉期眼上静脉显影并扩张,8例动脉期大脑中静脉显影并扩张。其中一例同时合并左侧大脑中动脉动脉瘤。结论B型超声及多排螺旋CT血管造影对诊断颈内动脉海绵窦瘘有重要的应用价值。 相似文献
82.
Watanabe A Nagaseki Y Ohkubo S Ohhashi Y Horikoshi T Nishigaya K Nukui H 《Clinical anatomy (New York, N.Y.)》2003,16(1):9-14
The dimensions of the 10 triangles around the cavernous sinus were measured to define the anatomical characteristics of the triangles and to compare their consistency in shape and area. Twelve tissue blocks containing the bilateral cavernous sinuses and medial two-thirds of the middle cranial fossae were obtained from Japanese adults at autopsy, fixed to a stereotactic frame, and examined with an operative microscope. The dimensions of each triangle were measured with calipers and compared, based on the same point and border. The anteromedial triangle and the superolateral (Parkinson's) triangle were more consistent in shape than the paramedial and oculomotor triangles, but the oculomotor triangle was larger in area than these other triangles. The posteromedial (Kawase's) triangle was more consistent in shape and larger than the anterolateral, lateral, and the posterolateral (Glasscock's) triangles. The anteromedial and superolateral (Parkinson's) triangles are important for the combined epi- and subdural approach to cavernous sinus lesions. The posteromedial (Kawase's) triangle is important for gaining access to the posterior cranial fossa from the middle cranial fossa. 相似文献
83.
Ramon Sanchez Richard K. Sibley Juan Rosai Ronald F. Dorfman 《Ultrastructural pathology》1981,2(2):101-119
Eleven cases of sinus histiocytosis with massive lymphadenopathy (SHML) involving lymph nodes were studied electron microscopically. Histiocytes were the most conspicuous element of the infiltrate. They could be divided into small and large forms, although transitions were apparent among them. Most of the small histiocytes were located in the medullary cords. The large histiocytes were predominantly seen within sinuses and were subdivided into two types on the basis of their appearance. The most distinctive feature of these histiocytes was the presence of lymphocytes, plasma cells, and neutrophils within their cytoplasm. Other cells present in the infiltrate were lymphocytes, plasma cells, and occasional neutrophils and mast cells. Blood vessels were prominent throughout. Virus particles, bacteria, and Langerhans granules were consistently absent. No morphologic clues were provided by this study as to the etiology of this disorder. 相似文献
84.
There are two sets of peripheral arterial chemoreceptors in the cat, the carotid bodies innervated by the carotid sinus nerve and the aortic bodies with afferents in the aortic depressor nerves. Reflex stimulation of ventilation in response to hypoxia is abolished acutely after interrupting the sensory pathway from the carotid body chemoreceptors in the cat even though the reflex pathway from the aortic body chemoreceptors is intact. However, in chronically maintained preparations, there is a restoration of the hypoxic response which is mediated by the aortic chemoreflex pathway. It was proposed that restoration was due to a ‘central reorganization’ of chemoreflex pathways which followed interruption of the sensory pathway from the carotid bodies and that the reorganization enhanced the efficacy of the aortic ventilation chemoreflex. This proposal was tested in the present experiments by measuring reflex ventilatory and cardiovascular responses to electrical stimulation of the sensory nerves containing aortic and carotid chemoreceptor afferents following bilateral interruption of carotid sinus nerves and carotid body resection. Responses measured acutely (1–6 h) after interruption were compared with those measured 60–80 and 110–140 days later. At 60–80 days, a chemoreflex response (increase in tidal volume of ventilation) to stimulation of the interrupted carotid sinus sensory pathway was markedly attenuated while the response to stimulation of the uninterrupted pathway in aortic depressor nerves was enhanced. At 110–140 days, the tidal volume response to carotid sinus nerve stimulation was greatly enhanced while the aortic depressor nerve response declined from the elevated level. There were significant but less pronounced changes in the response of other ventilatory and cardiovascular variables to aortic depressor nerve and carotid sinus nerve stimulation.The results support the idea that there is a ‘central reorganization’ of chemoreflex pathways which is reflected functionally by changes in the efficacy of reflexes evoked from aortic depressor nerve and carotid sinus nerve. The changes are analagous to those occurring in somatic reflexes during regeneration of sensory nerves. It is suggested that the changes in efficacy of carotid sinus nerve reflexes are due to a degenerative loss of synapses of the central projections of interrupted carotid sinus nerve sensory axons (degenerative atrophy) and subsequent regenerative like changes (regenerative proliferation) in the central projections. The changes in the efficacy of aortic depressor nerve reflexes may be attributed to formation of new synapses by converging central projections of this uninterrupted pathway (reactive synaptogenesis) and subsequent regression of the newly formed synapses. 相似文献
85.
Piette V Bousquet C Kvedariene V Dhivert-Donnadieu H Crampette L Senac JP Bousquet J Demoly P 《Allergy》2004,59(8):863-868
BACKGROUND: Involvement of paranasal sinuses has been suggested in allergic rhinitis but not clearly demonstrated. AIMS: To investigate the relationship between intermittent allergic rhinitis and computerized tomography (CT). METHODS: Twenty patients with intermittent rhinitis and sensitized to cypress pollens underwent unilateral nasal provocation tests (NPTs) using increasing concentrations of cypress pollens out of the pollen season. Sinus CT-scans were carried out just before a NPT and 24 h later. Nasal lavage was carried out just before a NPT, 30 min after a positive challenge and again 24 h later. Leucotriene C4/D4, intracellular adhesion molecule-1 and eosinophil cationic protein were measured in nasal secretions. RESULTS: Thirteen patients (65%) showed an alteration in their CT-scans after allergen challenge. Ten of them showed sinus changes controlateral to their allergenic provocation. Radiological changes mainly affected the osteomeatal complex and the ethmoid sinuses. Pre-existing abnormalities (13 of 20 cases) mainly concerned the maxillary sinuses. There was no correlation between CT-scan abnormalities and levels of mediators released in nasal secretions. CONCLUSIONS: We have shown that nasal allergen challenge can produce radiological changes in the paranasal sinuses. This mainly concerned the ethmoid sinuses. 相似文献
86.
上矢状窦三维断层解剖及其临床意义 总被引:4,自引:0,他引:4
目的:为给临床影像诊断提供解剖依据,方法:应用24例头部标本研究了上矢状窦的三维断层解剖,结果:在正中矢状断层内,上矢状窦呈前窄后宽的弯曲裂隙,在冠状和横断层中,上矢状窦呈圆形,椭圆形,三角形和楔形,并测量了有关数据,结论:上矢状窦在各断层内的形态与其和人体横断面及冠状面所成的角度有关。 相似文献
87.
在80侧成人颞骨干标本上,对面神经锥体段的埋藏位置及深度,面神经与面神经隐窝、鼓室窦三者之间的关系及其变异类型进行了应用解剖学研究。提出了耳科后鼓室进手术路中对面神经锥体段的予测方法。经90例手术验证有实用价值。 相似文献
88.
Sinusitis is one of the most common reasons patients visit their primary care physician. The etiology of sinusitis is multifactorial
in most cases. However, the final common pathway of disruption is usually made with a thorough history. The physical examination
is often unremarkable. Complaints of nasal obstruction, mucopuluent nasal drainage, and facial pain/pressure are most diagnostic
chronic sinusitis. Isolated headache is an uncommon presenting symptom. Computed tomography scans are the gold standard for
diagnostic imaging. They can be used both for diagnosis and surgical treatment. All chronic sinusitis patients, being considered
for endoscopic sinus surgery, should have failed a trial of maximal medical therapy. This includes a 4–6 wk course of oral
antibiotics, nasal steroids, topical nasal decongestants, and oral prednisone if possible. Patients who fail maximal medical
therapy have persistent symptoms that significantly effect their daily activities, have chronic abnormalities on computet
tomography scan, and are candidates for endoscopic sinus surgery. Appropriate patient selection and preoperative counseling
are key factors in patient satisfaction. Most patients with symptoms that significantly impact their daily activities will
receive marked improvement in symptoms after sinus surgery. Endoscopic sinus surgery has undergone radical changes in the
last 15 yr. Minimally invasive techniques, combined with advances in instrumentation and computers have reduced postoperative
discomfort and improved patient satisfaction. 相似文献
89.
A. S. Zagami G. A. Lambert 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,81(3):552-566
Summary Extracellular recordings were made in the thalamus of cats anaesthetized with chloralose and urethane following electrical,
mechanical and chemical stimulation of the superior sagittal sinus or middle meningeal artery. Facial receptive fields were
looked for using electrical and mechanical stimuli. The locations of fifty-six cells were verified histologically. Twenty
six cells were located in the ventroposteromedial nucleus (VPM) and six in its ventral periphery (VPMvp). All units in VPM
had facial receptive fields, usually involving the first trigeminal division. Cells with nociceptive receptive fields or responding
to the craniovascular application of bradykinin were often found in the periphery or “shell” region of VPM. Other craniovascular
nociceptive cells were found in VPMvp, in the posterior group and in the intralaminar complex. This study shows that craniovascular
afferents in the cat project to several thalamic nuclei and implicate VPM especially in craniovascular nociception. 相似文献
90.
O. E. Osadchii V. M. Pokrovskii I. L. Cherednik A. N. Kurzanov 《Bulletin of experimental biology and medicine》1993,116(1):759-761
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N
o
7, pp. 4–6, July, 1993 相似文献