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1.
BACKGROUND AND PURPOSE: The difficult transtemporal ultrasound window is a relatively frequent occurrence. The authors assessed if the thickness of the temporal bone squama as measured in the "bone window" of the head computerized tomography (CT) scan can predict the transtemporal acoustic window. METHODS: The authors retrospectively reviewed the head CTs on their bone window setting of patients in which nonimaging transcranial Dopplers (TCDs) had been performed. The thickness of the temporal squama in its thinnest portion was measured. The temporal TCD windows were graded in three classes: class 1 as good, class 2 when only a partial study is possible, and class 3 as an impossible ultrasonic window. In a case-control design, for every patient with any class 2 and 3 TCD temporal window, a patient with a class 1 window was randomly included from the same time period. RESULTS: Fifty-five temporal bones (56%) were class 1, 17 (17%) were class 2, and 27 (27%) were class 3. Bone thicknesses (in mm, mean +/- SD) were greater in those with poorer windows: class 1 = 2.67 +/- 0.70, class 2 = 4.06 +/- 0.56, and class 3 = 5.04 +/- 1.06, P < or = .0001 by Cusick's nonparametric test of trend. Temporal squama thickness of > or = 5 mm portends 86% sensitivity, 90% specificity, 70% positive predictive value, and a positive likelihood ratio of 8.6 for a class 3 transtemporal ultrasound window. CONCLUSION: Measurement of temporal bone thickness on the bone window setting of the head CT scan may be useful in identifying patients who are poor candidates for transcranial ultrasound.  相似文献   

2.
Jaroslaw Krejza  MD  PhD    Maciej Swiat  MD    Mikolaj A. Pawlak  MD  PhD    Grzegorz Oszkinis  MD  PhD    John Weigele  MD    Robert W. Hurst  MD    Scott Kasner  MD  PhD 《Journal of neuroimaging》2007,17(4):311-314
PURPOSE AND BACKGROUND: To determine whether the proportion of patients with suitable temporal bone acoustic windows is different for conventional transcranial Doppler sonography (TCD) and transcranial color-coded duplex sonography (TCCS), based on a head-to-head comparison in the same population of patients. SUBJECTS AND METHODS: Ninety patients, age 22-88 years (mean 57.1 +/- 11.7 years), 46 women and 44 men, 66 Caucasian, 19 African-American, and five Hispanic, underwent routine conventional TCD and the TCCS examination close in time to each other. Suitability of temporal bone acoustic window was defined by ability to insonate the middle and posterior and/or anterior cerebral arteries, while partial suitability was defined by ability to detect the posterior cerebral artery but not the middle cerebral artery. To compare proportions of suitable temporal bone windows for both sonographic methods, exact sign test by Liddell was used. RESULTS: Bilateral absence of temporal bone acoustic window was reported in six patients when studied with both conventional TCD and TCCS, whereas at least unilateral absence was reported in 10 patients. Partial, at least unilateral, suitability was reported in 11 patients with conventional TCD, and in 7 with TCCS. All differences in proportions were not significant (two-sided P>0.05). CONCLUSIONS: This study suggests that success rate of insonating the intracranial vessels through the temporal bone acoustic window is the same for conventional TCD and imaging TCCS.  相似文献   

3.
Jee-Hyun Kwon  MD  PhD  Jong S. Kim  MD  PhD  Dong-Wha Kang  MD  PhD  Kyun-Seop Bae  MD  PhD  Sun U. Kwon  MD  PhD 《Journal of neuroimaging》2006,16(4):347-352
BACKGROUND AND PURPOSE: Although transcranial Doppler (TCD) is useful for evaluation and treatment of ischemic stroke, temporal acoustic window failure (TAWF) limits its application. We performed this study to reveal whether initial brain CT of acute stroke patients predicted TAWF. METHODS: We performed TCD in 92 acute ischemic stroke patients (57 males, aged 38-84 years) with brain CT scans. We measured the thickness (BTW) and evaluated the texture of the temporal bone in acoustic windows shown in the CT scan with the use of picture archiving and communication system. The bone mineral density (BMD) of the vertebral bodies, femurs, and whole body was also measured. RESULTS: Doppler signals were adequately obtained in 121 (65.8%) of the 184 middle cerebral arteries (MCA) from both cerebral hemispheres. BTW and inhomogeneity of temporal bone, besides age, sex, and hypercholesterolemia, was strongly correlated with TAWF. BMD was not directly correlated with TAWF, but inhomogeneous temporal bone was correlated with lower BMD scores. If the brain CT scan showed thick (BTW >or= 2.7 mm) and inhomogeneous temporal bone, the possibility of TAWF was 93.5%, while if brain CT scan showed thin (BTW < 2.7 mm) and homogenous temporal bone, it was only 5.4%. CONCLUSIONS: The texture as well as the thickness of the temporal bone was the most important determinant of TAWF. When acute stroke patients had thin and homogeneous temporal bones in initial brain CT scan, TAWF was very rare, and loss of MCA signals on TCD specifcally indicated the absence of blood flow in MCA.  相似文献   

4.
BACKGROUND: Paradoxical thrombotic embolism via right-to-left shunt is a risk factor for ischemic stroke, especially in younger subjects. Transtemporal Doppler shows a sensibility and specificity in the detection of patent foramen ovale comparable to that of transesophageal echocardiography, but even younger patients may not have a sufficient acoustic temporal bone window (up to 10%). METHODS AND RESULTS: We thus studied prospectively in 74 patients subsequent to a recent stroke of undetermined origin whether transforaminal (foramen magnum) Doppler is an alternative to transtemporal Doppler in the detection and quantification of right-to-left cardiac shunt. We found a highly significant correlation between the two methods. CONCLUSIONS: We conclude that transforaminal Doppler may be a complement and alternative to transtemporal Doppler and thus improve its value as a screening method for right-to-left cardiac shunt due to patent foramen ovale.  相似文献   

5.
Frontal bone windows for transcranial color-coded duplex sonography   总被引:3,自引:0,他引:3  
BACKGROUND AND PURPOSE: The use of the conventional temporal bone window for transcranial color-coded duplex sonography (TCCS) often results in difficulties in obtaining angle-corrected flow velocity measurements of the A2 segment of the anterior cerebral artery, the posterior communicating artery, and the midline venous vasculature because of the unfavorable insonation angle. The same applies to B-mode imaging of the frontal parenchyma. However, transorbital TCCS raises problems with the insonation of the orbital lens. To overcome these drawbacks, we studied the feasibility of frontal bone windows for TCCS examinations. METHODS: In 75 healthy volunteers (mean age, 45.3+/-17.0 years; age range, 17 to 77 years), the circle of Willis and the venous midline vasculature were insonated through a lateral and paramedian frontal bone window. Insonation quality of parenchymal structures (B-mode) was graded on a 3-point scale depending on the visibility of typical parenchymal landmarks. In a similar manner, the quality of the color-/Doppler-mode imaging of the arteries of the circle of Willis and the internal cerebral veins was assessed. In 15 patients (mean age, 62.7+/-13.7 years; age range, 33 to 83 years), the color-/Doppler-mode imaging quality of the intracranial vessels before and after application of an ultrasound contrast-enhancing agent was compared. RESULTS: B-mode insonation quality was optimal to fair in 73.3% of cases using the lateral and in 52.0% of cases using the paramedian frontal bone window, with defined parenchymal structures used as reference. Insonation quality decreased in those older than 60 years. In those younger than 60 years, angle-corrected flow velocity measurements of the A2 segment of the anterior cerebral artery and the internal cerebral vein were possible in 73.6% and 60.0%, respectively. Contrast enhancement resulted in a highly significant improvement in the imaging quality of the intracranial vessels. CONCLUSIONS: The transfrontal bone windows offer new possibilities for TCCS examinations, although the insonation quality is inferior to the conventional temporal bone window in terms of failure of an acoustic window. This can be compensated for by application of an ultrasound contrast-enhancing agent.  相似文献   

6.
The aim of the study was to evaluate the diagnostic potential of galactose-based microbubble suspension (Levovist) in patients with acute cerebrovascular disease and inadequate transtemporal acoustic window, when examined by transcranial Doppler (TCD). We studied 10 patients with either transient ischemic attack (no. = 3) or stroke (no. = 7). Inadequate transtemporal acoustic window was unilateral in 3 patients and bilateral in the remaining 7 patients. Signals from middle, anterior, and posterior cerebral arteries (MCA, ACA, PCA) were recorded after injecting Levovist 300 mg/ml. Six patients needed 3 injections of Levovist, 1 patient two, and 3 patients one. Mean +/- SD duration of optimal signal enhancement was 175.2 +/- 53.2 s, range 70-290 s. Doppler waveform analysis was possible in 14 (82.3%) MCA, 11 (65%) ACA, and 9 (53%) PCA. Levovist improved the reliability of TCD in patients with acute cerebrovascular disease and insufficient transtemporal insonation.  相似文献   

7.
背景:种植体型牙槽嵴牵张器的初期稳定性取决于骨-牵张器界面适当的应力分布,了解植入初期的生物力学改变有助于提高种植体型牙槽嵴牵张器的临床成功率。 目的:通过有限元法了解骨质结构对牵张初期应力分布和牵张器、骨段变形情况的影响。 方法:利用CAD软件绘制由输送段和基段组成的牵张器模型(长11 mm,直径3.7~ 4.1 mm),同一软件绘制4个下颌骨节段模型模拟4类不同骨质的下颌骨。装配后导入ANSYS软件形成由10 079~11 456单元和17 299~20 101节点构成的有限元模型,利用该系列有限元模型分析松质骨、密质骨的应力改变和输送骨段、牵张器的变形情况。 结果与结论:最大应力均出现在输送骨段,随骨质量下降而增大;骨最大变形出现在输送段边缘,随着骨质量下降而增大;牵张器的下沉也随着骨质量的下降而增大。结果表明随着骨质量的下降,最大应力与变形均明显增大。骨弹性模量的下降将增大牵张成骨失败的风险。  相似文献   

8.
Echocontrast agents (ECA) are known to improve transcranial color-coded duplex (TCCD) imaging, but its diagnostic benefit in the routine clinical setting has not clearly been defined. The authors investigated the diagnostic benefit of ECA application in 54 patients with insufficient transtemporal bone window, consecutively referred to their ultrasound laboratory. According to the precontrast imaging quality, patients were assigned to three categories: A, no intracranial structures or vessel segments visible on B-mode imaging and TCCD (n = 5); and intracranial structures visible on B-mode imaging and vessel segments less than 5 mm in length (B, n = 21), or larger than 5 mm in length (C, n = 28) visible on TCCD. The effect of the echocontrast enhancement was assessed with respect to signal enhancement, imaging quality, and diagnostic confidence. In 49 out of 54 patients (91%), a significant improvement of the imaging quality was noted, enabling 43 (80%) neurovascular diagnoses of sufficient diagnostic confidence. The diagnostic ECA effect was strongly dependent on the precontrast imaging quality: upon echoenhancement, a satisfactory image quality was obtained in none of the patients of category A, as opposed to 16 (76%) and 27 (96%) patients of categories B and C, respectively. In summary, in 80% of our consecutive patient series with insufficient transtemporal bone window, application of ECA allowed for a conclusive TCCD study. Properties of the transtemporal precontrast scans are strongly predictive of the diagnostic benefit and should be taken into the decisive consideration.  相似文献   

9.
Background: Transcranial color-coded sonography (TCCS) allows direct observation of arteries and the possibility of correcting the insonation angle for reliable evaluation of hemodynamics. We obtained TCCS reference values of the cerebral hemodynamics after correction of insonation angles. Methods: We studied 195 healthy adults equally allocated into 3 age groups: 18-40, 41-60, and greater than or equal to 61 years. The middle (MCA), anterior (ACA), and posterior cerebral arteries (PCA) were evaluated through the temporal acoustic window using conventional pulsed transcranial Doppler and TCCS. Peak systolic, end diastolic, and mean blood flow velocities were registered, as well as pulsatility and resistance indices at 0° and with correction by alignment of insonation angle parallel to the blood flow vector. We derived normative values assuming both the parametric and nonparametric distributions. Results: We excluded 33 participants due to inadequate acoustic window (10.3%), carotid disease (2.1%), and embryonic variants (4.6%), leaving out 162 for final analysis (50% female, median age 48 years). The 2.5th-97.5th percentiles of the corrected angle for MCA was 0°-60°, ACA 0°-44°, and PCA 30°-60°. After angle correction, 2.5th-97.5th percentiles for flow velocity of MCA, ACA, and PCA were 37.7-112.5 cm/s, 25.6-71.2 cm/s, and 29.2-80.8 cm/s, respectively. There were wide discrepancies between hemodynamics values obtained with insonation angles at 0° and after angle correction. No differences were found between ultrasound methods at exactly 0° or between hemispheres, however, there were differences according to age and sex. Conclusions: Specific normative tables should be used in TCCS when the corrected angle is greater than 0° since the hemodynamics values greatly differ after correction of the insonation angle. Further studies are necessary to determine critical cutoffs indicating disease.  相似文献   

10.
Proper assessment of intracranial arteries by transcranial Doppler sonography (TCD) in patients with intracranial stenoses is occasionally made difficult by an insufficient temporal bone window, an unfavourable insonation angle, or low flow velocity or volume. This condition is frequently found in Chinese. In these cases, echocontrast could be helpful. We investigated 48 temporal windows of 24 acute Chinese stroke patients with insufficient native transtemporal insonation conditions before and after the application of the echo enhancer Levovist (galactose/palmitic acid) by an injection pump. We classified the signal quality from four segments of the main intracranial arteries: anterior cerebral artery (A1), main stem of the middle cerebral artery (MCA, M1), intracranial segment of the carotid artery (C1), and posterior cerebral artery (P1). The signal quality was classified as follows: 0 = no signal, 1 = poor, envelope curve does not follow spectrum, 2 = adequate, envelope curve follows spectrum. As compared to the pre-contrast scans, echocontrast allowed for more segments to be evaluated by pulsed Doppler sonography. Before Levovist, only 12% of the segments could be detected, after Levovist 63%. For all arteries, signal quality was better after Levovist, p between 0.0180 and 0.0003. In 3 patients, MCA stenoses with peak systolic Doppler flow velocities above 160 cm/s were found only after Levovist. In patients with poor pre-contrast detection, echocontrast-enhanced TCD allows for more arterial segments to be insonated and for the detection of stenoses unnoted during the non-enhanced investigation.  相似文献   

11.
BACKGROUND AND PURPOSE: The insonation of the posterior communicating artery (PcomA) is often hampered by the unfavorable insonation angle when the temporal acoustic bone window (TBW) is used. This problem may be ameliorated by a lateral frontal bone window (LFBW). This study evaluated the TBW and LFBW for the assessment of collateral intracranial flow conditions and aimed at defining diagnostic transcranial color-coded duplex sonography (TCCS) criteria that do not need compression maneuvers. METHODS: The A1 segment of the anterior cerebral artery (ACA), the PcomA, and the P1 segment of the posterior cerebral artery (PCA) were insonated by TCCS in 40 controls and 20 patients (16 internal carotid artery [ICA] occlusions or high grade stenoses, 3 middle cerebral artery stenoses or occlusions, 1 PCA stenosis). RESULTS: Detection rates for the A1 ACA and P1 PCA were higher for the TBW (94%, 98%) compared to the LFBW (86%, 81%) in controls. The PcomA was identified more frequently through the LFBW (86%) compared to the TBW (80%). Through the LFBW angle, corrected flow velocity (FV) measurements were possible for the PcomA with an average correction of 6.5 degrees. In controls, in > 80% of identified PcomAs, flow was directed towards the ICA. Side to side differences were below 7% for peak systolic FVs. In the patients with ICA disease, a flow reversal in the ipsilateral A1 ACA and a FV difference of > 30% seemed feasible for diagnosis of anterior communicating artery crossflow. Criteria for PcomA crossflow were side differences of FVs in the PcomA of > or = 30% and in the P1 PCA of > or = 20%. CONCLUSIONS: The LFBW proved useful as a complementary insonation plane to assess intracranial crossflow conditions, especially via the PcomA. We were able to define TCCS criteria for functional relevant collateralization without the need of compression maneuvers.  相似文献   

12.
OBJECTIVES: Proper assessment of the intracranial arteries by transcranial color-coded duplex sonography (TCCD) is occasionally made difficult by an insufficient temporal bone window, an unfavorable insonation angle, or low flow velocity or volume. In these cases, echocontrast could be helpful to increase the diagnostic confidence or to make the diagnosis at all. MATERIAL AND METHODS: We investigated 67 temporal windows of 47 patients with insufficient native transtemporal insonation conditions before and after the application of the second-generation (gas-filled) microbubble contrast agent Sonovue (in 20 patients out of these 47, both temporal windows were insufficient, in the remaining 27 only one side). RESULTS: As compared to the precontrast scans, echocontrast allowed for more segments to be evaluated by pulsed Doppler sonography (p < 0.0001) and for longer lumen segments to be displayed on color mode (p < 0.0001). With the help of contrast medium, flow velocity in the middle cerebral artery could be measured through 65 windows as compared to only 26 windows before contrast was applied (p < 0.0001). CONCLUSIONS: In patients with poor precontrast visualization of intracranial arteries, echocontrast-enhanced TCCD is very helpful.  相似文献   

13.
Clinical Applications of Transcranial Color-Coded Duplex Sonography   总被引:11,自引:0,他引:11  
Transcranial color-coded duplex sonography (TCCS), in contrast to "blind" conventional transcranial Doppler sonography (TCD), enables a sonographer to outline the intracranial bony and parenchymal structures, visualize the basal cerebral arteries in color, and measure angle-corrected blood flow velocities in a specific site of the artery in question. This makes measurements of flow velocity more valid than those obtained with conventional TCD. TCCS is becoming a reliable tool for detecting the occlusion and narrowing of major intracranial arterial trunks. TCCS can image the collateral flow through the anterior and posterior communicating arteries in patients with unilateral, high-grade stenosis or occlusion of the extracranial internal carotid artery, without using potentially dangerous compression tests. Large and medium-sized arteriovenous malformations can also be detected with TCCS. The rapid sonographic assessment of cerebral hemodynamics in a neurosurgical patient with increased intracranial pressure can guide further management. The use of sonographic contrast agents can increase the number of conclusive TCCS studies in patients with insufficient acoustic windows.  相似文献   

14.
BACKGROUND AND PURPOSE: Transcranial color-coded duplex sonography (TCCS) of intracranial veins and sinuses in adults is a new, emerging application of ultrasonographic imaging. This study reports a standardized examination protocol for venous TCCS and provides reference data for clinical application. METHODS: In 130 healthy volunteers (mean age, 45.9+/-16.9 years; range, 14 to 77 years) the intracranial venous system was examined using frequency-based transtemporal TCCS. Identification rate, blood flow velocity, resistance index, and systolic/diastolic ratio were recorded for each examined venous vessel. RESULTS: Intracranial veins and sinuses show a low pulsatile forward flow with maximal systolic blood flow velocity up to 20 cm/s. Significant side differences of blood flow velocity in the paired venous structures could not be detected. Venous flow velocities decreased with age, whereas resistance indices and systolic/diastolic ratios increased. Women showed higher flow velocities than men. Mean identification rates for all age groups ranged from 70% to 90% for the deep middle cerebral vein, the basal cerebral vein, and the great cerebral vein of Galen. The straight sinus, the transverse sinus, and the rostral part of the superior sagittal sinus could be detected in 55% to 70% of cases. Detection rates were dependent on age and decreased as age increased. CONCLUSIONS: Venous TCCS can reliably image a significant part of the cerebral venous system. This method can provide information on venous hemodynamics in normal subjects and pathological cases.  相似文献   

15.
摘要 背景:目前异种松质骨作为组织工程材料较为多见,而皮质骨因其难以降解,孔隙率低等原因限制了其使用。但皮质骨具有许多松质骨不具备的优越性,如生物力学方面,如何开发利用皮质骨是课题研究的重点。 目的:观察兔骨髓间充质干细胞复合带部分松质骨小牛皮质骨支架材料植入兔体内后血管内皮细胞生长因子表达。 方法:健康1月龄新西兰大白兔4只用于干细胞提取;3月龄新西兰大白兔60只,在髂骨翼分别植入骨髓间充质干细胞成骨诱导后复合异种骨,单纯异种骨,自体髂骨。术后4,8,12,24周取材RT-PCR检测血管内皮细胞生长因子的表达。 结果与结论:血管内皮细胞生长因子的表达情况:在各时间点,单纯异种骨组低于骨髓间充质干细胞成骨诱导后复合异种骨组和自体髂骨组(P < 0.05)。术后第4周时,骨髓间充质干细胞成骨诱导后复合异种骨组低于自体髂骨组(P < 0.05),在术后第8,12,24周时,两组差异无显著性意义(P > 0.05)。提示兔骨髓间充质干细胞复合带部分松质骨的小牛皮质骨支架材料植入新西兰兔体内具有较好的血管生成能力。 关键词:成骨诱导;骨髓间充质干细胞;带部分松质骨小牛皮质骨;血管内皮细胞生长因子;骨科生物材料 doi:10.3969/j.issn.1673-8225.2010.34.005  相似文献   

16.
Gerriets T  Seidel G  Fiss I  Modrau B  Kaps M 《Neurology》1999,52(6):1133-1137
OBJECTIVE: To evaluate the diagnostic efficiency and accuracy of contrast-enhanced transcranial color-coded sonography (CE-TCCS). BACKGROUND: TCCS is hampered by insufficient ultrasonic penetration in 20% of cerebrovascular patients. METHODS: In 47 patients whose basal arteries could not be assessed adequately, 59 TCCS examinations were performed before and after administration of the ultrasonic contrast agent (CA) Levovist. The assessability of different basal cerebral arteries after CA administration was evaluated off-line. Angiographic records were available from 11 patients. RESULTS: Satisfactory investigation of the middle cerebral artery, the anterior cerebral artery, the P1 and P2 segments of the posterior cerebral artery, and the supraclinoid portion of the internal carotid artery siphon was possible in 5.1%, 28.8%, 35.6%, 55.9%, and 47.5% of patients before, and in 84.7%, 91.5%, 93.2%, 94.5%, and 93.2% of patients after contrast enhancement. Stenoses or occlusions of basal cerebral arteries were registered in 28 patients (60%). CE-TCCS diagnosis was confirmed by digital subtraction angiography or magnetic resonance angiography in 10 of the 11 patients, leading to positive and negative predictive values of 0.86 and 1.00. CONCLUSION: Contrast enhancement improves the diagnostic potential of TCCS significantly in patients with temporal bone window failure, and proved to be a reliable method for detecting middle cerebral artery and siphon occlusion.  相似文献   

17.
背景:传统的松质骨孔隙率检测方法如直接法、气体膨胀法、压汞法、密度法和吸渗法等测量方法存在效率低、劳动强度大和工作繁杂等不足。 目的:利用MATLAB图像处理松质骨切片,计算松质骨孔隙率。 方法:运用MATLAB处理图像的方法,通过对染色后的松质骨切片图像进行去除灯光不均、图像增强、二值化、移除干扰目标等处理,最后得到二值化的二维矩阵。 结果与结论:切片图像由骨质和孔隙构成,对切片图像进行分割并计算孔隙率。主要解决了图像信息中由光照强度不均和其他干扰而影响统计的问题。利用MATLAB骨切片图像处理与分析方法不仅可以用来进行松质骨孔隙率的测量,而且能用来研究孔隙率的分布和变化规律。选取图像不同区域计算出各个选取区域孔隙率大小,用来分析切片孔隙分布的情况,这对于研究松质骨结构提供了一种方法与思路。  相似文献   

18.
It is well known that the case of multiple myeloma shows punched-out lesions of the cranium without intracranial hypertension. In this paper a case of multiple myeloma is reported showing intracranial hypertension due to a large tumor that developed in the left parietal bone. There are only 13 case reports about cranial mass lesion of multiple myeloma since 1928. A 52 year-old female was admitted to Iwate Prefectural Isawa Hospital suffering from headache, nausea and vomiting. She had been already diagnosed as multiple myeloma and treated with chemotherapy using Cyclophosphamide, Melphalan and Prednisolone for 2 years. On admission, a large subcutaneous mass was presented on the left parietal region. Craniogram revealed large osteolytic lesion of the left parietal bone and 3 punched-out lesions of the frontal bone. CT scan revealed a large mass lesion in the left epidural space, diploe and subcutaneous space. Angiography showed avascular area. Brain scintigram showed diffuse hot area. Other skeletal bones showed no abnormality. Laboratory examination revealed high concentration of gamma-globulin and high erythrocyte sedimentation rate. Electrophoresis showed high value of immunoglobulin G; immunoglobulin assay was as follows: IgG-6000 mg/dl, IgA-150 mg/dl, IgM-410 mg/dl, IgE-0 mg/dl. Serum electrolytes were within normal limits. Urine didn't include Bence-Jones protein. The patient was diagnosed as multiple myeloma suffering from intracranial hypertension caused by large tumor which developed in the left parietal bone. On the operation, large tumor was existed in the epidural and subcutaneous space invading into the diploe but without infiltration into the dura mater or cerebral cortex.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
Background and purposeTranscranial colour-coded sonography (TCCS) has been proven to be a method of high performance in the diagnosis of spasm of the middle cerebral artery (MCA). Relevant data concerning the anterior cerebral artery (ACA) varies amongst studies. The aim of this study was to assess the performance of TCCS in the diagnosis of spasm affecting the ACA.Material and methodsNinety-two patients (39 women and 53 men, age 51 ± 12.1 years) were examined using TCCS before cerebral angiography. Of 184 examined ACAs, only 133 arteries could be visualized due to insufficiency of the temporal acoustic window. Therefore, only 15 out of 25 arteries in which vasospasm was diagnosed with angiography (by two neuroradiologists not informed about the sonographic findings) could be included in the analysis. Receiver operating characteristic (ROC) curves were constructed for specific blood flow velocities: peak systolic (PSV), mean (M) and end-diastolic (EDV). The area under the ROC curve was used to measure the overall diagnostic performance of TCCS.ResultsThe area under the ROC curve for PSV was 0.83, which indicates good performance. The PSV threshold of 98 cm/s corresponded to maximum accuracy and was associated with 71% sensitivity vs. 88% specificity. Average systolic blood flow velocity in the vessels with vasospasm was 129 cm/s, whereas in unaffected vessels it was 76 cm/s.ConclusionsThe accuracy of TCCS in the diagnosis of ACA spasm is relatively high – the value of the area under the ROC amounts to 0.83. PSV performs best and the threshold of 98 cm/s is associated with an optimal trade-off between sensitivity and specificity.  相似文献   

20.
背景:异种脱蛋白骨与宿主骨骼具有相同的结构,抗原性较低,不会或很少引起宿主免疫反应。 目的:观察自制小牛脱蛋白松质骨与兔皮质骨来源成骨细胞的生物相容性。 方法:将自制小牛脱蛋白松质骨与新西兰大白兔成骨细胞复合培养,设单纯成骨细胞对照组,观察细胞生长、支架材料降解及细胞与支架材料附着情况。 结果与结论:小牛脱蛋白松质骨为多孔网状,孔隙互相通连,细胞在其上附着、生长、增殖。复合培养第3天,有较多的细胞黏附并铺展在支架上;第6天,细胞在支架上完全伸展,呈长梭形;第10天细胞分泌较多基质,重叠生长并连接成网状。实验组复合培养9,12 d时成骨细胞的增殖及分泌情况明显优于对照组(P < 0.05),碱性磷酸酶活性与骨钙素表达高于对照组(P < 0.05)。表明兔皮质骨成骨细胞增殖和成骨能力强,自制的小牛脱蛋白松质骨具有骨诱导性,二者复合具有良好的生物相容性。  相似文献   

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