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91.
Carotid endarterectomy (CEA) is the main treatment for atherosclerotic plaque of the cervical internal carotid artery. The surgical anatomy of the carotid arteries was studied in the carotid triangle of 49 cadavers. The carotid bifurcation was located at the level of the lower third of C-3. The superior thyroid artery arose from the anterior wall of the external carotid artery in 70% of specimens and from the distal portion of the common carotid artery in 30%. The lingual artery arose as a separate trunk between the origins of the superior thyroid and facial arteries in 81% of specimens, with the facial artery from a common trunk in 18%, and with the superior thyroid artery in 1%. The occipital artery arose from the posterior aspect of the external carotid artery above the level of origin of the facial artery in 57% of specimens, between the origins of the facial and lingual arteries in 32%, and below the origin of the lingual artery in 11%. The origin of the occipital artery was positioned low and the distal portion of the occipital artery was crossed by the hypoglossal nerve in 20%. The ascending pharyngeal artery arose from the posterior wall of the external carotid artery above the level of origin of the lingual artery in 66% of specimens, below the origin of the lingual artery in 9%, from the proximal portion of the occipital artery in 19%, from the carotid bifurcation in 2%, and from the internal carotid artery in 2%. The branches of the external carotid artery are the key landmarks for adequate exposure and appropriate placement of cross-clamps on the carotid arteries. It is necessary to understand the surgical anatomy of the carotid arteries to carry out successful removal of plaque and minimize postoperative complications in a bloodless surgical field.  相似文献   
92.
Tanaka S  Nagashima T  Hori T 《Neurologia medico-chirurgica》1998,38(12):812-7; discussion 817-8
The use of monoclonal antibodies to the tumor necrosis factor (TNF) receptors, the TNF-p55 receptor (TNF-p55R) and the TNF-p75 receptor (TNF-p75R), was evaluated to reduce the effects of TNF caused by binding to TNF-p75R. Competitive binding of anti-TNF-p55R (mAbp55R) and anti-TNF-p75R monoclonal antibodies (mAbp75R) with iodine-125-labeled TNF-alpha to GL-9 glioma cells and U937 histiocytic lymphoma cells was evaluated. The effects of mAbp55R and mAbp75R on the growth suppression by TNF-alpha of GL-9 cells and TNF-alpha production in U937 cells were also examined. mAbp75R bound to U937 cells competitively with TNF-alpha and suppressed TNF-alpha production by U937, but had no effect on the growth inhibition of GL-9 human glioma cell by TNF-alpha in vitro. These findings suggest that co-administration of TNF-p75R antagonist with TNF-alpha may decrease the toxicity of TNF-alpha administration resulting in a better therapeutic result.  相似文献   
93.
CT assessment of the inferior peripancreatic veins: clinical significance   总被引:7,自引:0,他引:7  
OBJECTIVE: The purpose of this study was to evaluate and clarify the clinical significance of CT scans of the inferior peripancreatic veins. MATERIALS AND METHODS: Forty-three patients with suspected pancreatic disease underwent three-phase helical CT (collimation, 5 mm; reconstruction, 2.5 mm; scan delay, 30, 60, and 150 sec). The frequency of visualization on CT of the anterior and posterior inferior pancreaticoduodenal veins, inferior pancreaticoduodenal vein, and first jejunal trunk was assessed and correlated with angiographic and pathologic findings. RESULTS: The frequency of visualization of normal inferior peripancreatic veins in patients (n = 22) with a normal portomesenteric vein was 36% for the anteroinferior pancreaticoduodenal vein, 36% for the posteroinferior pancreaticoduodenal vein, 59% for the inferior pancreaticoduodenal vein, and 100% for the first jejunal trunk. The smaller inferior peripancreatic veins were frequently not visualized when normal. In patients (n = 13) with pancreatic carcinoma involving the portosuperior mesenteric vein, all of the inferior peripancreatic veins were dilated and easily recognizable. When the tumor did not involve the portosuperior mesenteric vein but did involve the anteroinferior pancreaticoduodenal, posteroinferior pancreaticoduodenal, and inferior pancreaticoduodenal veins (n = 8), some of the other peripancreatic veins (first jejunal trunk, anterior and posterior superior pancreaticoduodenal veins, and gastrocolic trunk) were dilated. Dilatation indicated tumor extension to the third portion of the duodenum. In patients (n = 7) with involvement of the inferior pancreaticoduodenal vein, the first jejunal trunk, or both without the involvement of the portosuperior mesenteric vein, dilatation of the other peripancreatic veins (anteroinferior pancreaticoduodenal vein, posteroinferior pancreaticoduodenal vein, anterosuperior pancreaticoduodenal vein, posterosuperior pancreaticoduodenal vein, and gastrocolic trunk) indicated tumor invasion of only the second portion of the extrapancreatic nerve plexus (n = 4) and tumor invasion of both the second portion of the extrapancreatic nerve and the mesenteric root (n = 3). CONCLUSION: Dilatation of peripancreatic veins with nonvisualization of inferior peripancreatic veins suggests tumor invasion of peripancreatic tissue.  相似文献   
94.
HepaSphere微球栓塞治疗高流量动静脉畸形   总被引:1,自引:0,他引:1  
目的 探讨HepaSphere微球血管内栓塞治疗高流量动静脉畸形(artefiovenous inalforma-tions,AVM)的疗效.方法 HepaSphere微球吸水后膨胀变软、直径大小可控制.13例AVM患者采用HepaSphere微球血管内栓塞治疗,其中3例栓塞后联合手术治疗.随访3个月至3年,根据临床症状的改善情况和影像学检查资料评价疗效.结果 13例共进行28次栓塞治疗,10例单纯栓塞、3例(2例颌面部、1例肺部AVM)栓塞后手术完全切除,弥漫性AVM多次栓塞后症状均有所改善.组织学显示HepaSphere微球充填血管导致血管腔阻塞,血管壁炎性反应轻微.结论 HepaSphere微球血管内栓塞治疗高流量AVM安全有效,对弥漫性AVM需要联合多种方法治疗.  相似文献   
95.
MRI of hyperpolarized 129Xe dissolved in pulmonary tissues, and blood has the potential to offer a new tool for regional evaluation of pulmonary gas exchange and perfusion; however, the extremely short T and low magnetization density make it difficult to acquire the image. In this study, an ultrashort echo‐time sequence was introduced, and its feasibility to quantitatively assess emphysema‐like pulmonary tissue destruction by a combination of dissolved‐ and gas‐phase 129Xe lung MRI was investigated. The ultrashort echo‐time has made it possible to acquire dissolved 129Xe images with reasonably high spatial resolution of 0.625 × 0.625 mm2 and to obtain T of 0.67 ± 0.30 ms in a spontaneously breathing mouse at 9.4 T. The regional dynamic alveolar gas uptake as well as subsequent transport by pulmonary blood flow was also visualized. The ratio of 129Xe magnetization that diffused into the septa relative to the gas‐phase magnetization F was regionally evaluated. The mean F value of elastase‐treated mice was 2.28 ± 0.46%, which was significantly reduced from that of control mice 3.41 ± 0.48% (P = 0.0052). This reflects the reduced uptake efficiency due to alveolar tissue destruction and is correlated with the histologically derived alveolar surface‐to‐volume ratio. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
96.

Introduction

A physical 3-dimensional phantom that simulates PET/SPECT images of static regional cerebral blood flow in grey matter with a realistic head contour has been developed. This study examined the feasibility of using this phantom for evaluating PET/SPECT images.

Methods

The phantom was constructed using a transparent, hydrophobic photo-curable polymer with a laser-modelling technique. The phantom was designed to contain the grey matter, the skull, and the trachea spaces filled with a radioactive solution, a bone-equivalent solution of K2HPO4, and air, respectively. The grey matter and bone compartments were designed to establish the connectivity. A series of experiments was performed to confirm the accuracy and reproducibility of the phantom using X-ray CT, SPECT, and PET.

Results

The total weight was 1997 ± 2 g excluding the inner liquid, and volumes were 563 ± 1 and 306 ± 2 mL, corresponding to the grey matter and bone compartments, respectively. The apparent attenuation coefficient averaged over the whole brain was 0.168 ± 0.006 cm?1 for Tc-99 m, which was consistent with the previously reported value for humans (0.168 ± 0.010 cm?1). Air bubbles were well removed from both grey-matter and bone compartments, as confirmed by X-ray CT. The phantom was well adapted to experiments using PET and SPECT devices.

Conclusion

The 3-dimensional brain phantom constructed in this study may be of use for evaluating the adequacy of SPECT/PET reconstruction software programs.  相似文献   
97.

Objectives

The purposes of this MR-based study were to calculate q-space imaging (QSI)–derived mean displacement (MDP) in meningiomas, to evaluate the correlation of MDP values with apparent diffusion coefficient (ADC) and to investigate the relationships among these diffusion parameters, tumour cell count (TCC) and MIB-1 labelling index (LI).

Methods

MRI, including QSI and conventional diffusion-weighted imaging (DWI), was performed in 44 meningioma patients (52 lesions). ADC and MDP maps were acquired from post-processing of the data. Quantitative analyses of these maps were performed by applying regions of interest. Pearson correlation coefficients were calculated for ADC and MDP in all lesions and for ADC and TCC, MDP and TCC, ADC and MIB-1 LI, and MDP and MIB-1 LI in 17 patients who underwent subsequent surgery.

Results

ADC and MDP values were found to have a strong correlation: r?=?0.78 (P?=?<0.0001). Both ADC and MDP values had a significant negative association with TCC: r?=?–0.53 (p?=?0.02) and –0.48 (P?=?0.04), respectively. MIB-1 LI was not, however, found to have a significant association with these diffusion parameters.

Conclusion

In meningiomas, both ADC and MDP may be representative of cell density.

Key Points

? Diffusion-weighted MRI offers possibilities to assess the aggressiveness of meningiomas. ? The q-space imaging-derived mean displacement correlates strongly with apparent diffusion coefficients. ? Both diffusion parameters showed a strong negative association with tumour cell counts. ? Derived mean displacement may help assess the aggressiveness of meningiomas preoperatively.  相似文献   
98.
To elucidate the relation between glucose tolerance and myocardial uptake of F-18 fluorodeoxyglucose (FDG), FDG-PET with 75 g oral glucose loading was performed on 43 coronary artery disease patients (twice in 2 patients). The patients were divided into 4 groups based on the blood glucose level (BS) and the insulinogenic index (II): group 1, normal (n = 9); group 2, impaired glucose tolerance (IGT, n = 12); group 3, mild diabetes mellitus (DM) (II > 0.4, n = 12); and group 4, severe DM (II < 0.4, n = 12). Percent (%) dose uptake of FDG in the normal regions of the myocardium was not significantly different in groups 1,2, and 3, but it was much lower in group 4 than in groups 1 and 2. In groups 2,3, and 4, % dose uptake showed a definite negative correlation with BS 60 min after glucose loading (r = -0.450, p < 0.05), and a close positive correlation with II (r = 0.363, p < 0.05). These findings indicate that myocardial FDG uptake in normal regions is not greatly impaired in patients with IGT or mild DM. Myocardial viability can be assessed by oral glucose loading in patients with IGT and mild DM as well as in patients with normal glucose tolerance.  相似文献   
99.
BACKGROUND: Increasing evidence supports the sentinel lymph node (SN) concept for melanoma and breast cancers. SN biopsy may replace routine lymph node dissection in the treatment of these cancers. But there are little data evaluating this concept in patients with gastric cancer. The objective of this study was to test the feasibility of SN mapping in gastric cancers by using the dual-mapping procedure with dye and radioactive colloid. STUDY DESIGN: Thirty-one consecutive patients preoperatively diagnosed as T1-2 and N0 underwent SN biopsy using the dual-mapping procedure. Distributions of SNs identified by the dye-guided technique (blue nodes; BNs) were compared with those identified by the gamma probe guided technique (hot nodes; HNs). RESULTS: Among the 31 patients, 7 were found to have lymph node metastases. All positive nodes were detected by SN biopsy using the dual method. So, an accuracy rate of 100% was achieved in predicting the status of regional lymph nodes. Both BNs and HNs were identified in 28 of 31 patients (90%), but significant discrepancy of distribution was noted between BNs and HNs. Among the 28 patients with identified BNs, there was one metastasis in a non-BN. So the accuracy rate was 96% for the dye-guided technique. In contrast, among the 28 patients with identified HNs, 2 patients had metastasis in non-HNs, making the accuracy rate 93% for the gamma probe-guided technique. CONCLUSIONS: SN mapping is feasible in gastric cancer, but the dye-guided and gamma probe-guided techniques are complementary. So we recommend the dual-mapping procedure.  相似文献   
100.
Patients who require management in the intensive care unit (ICU) for complications after allogeneic hematopoietic stem-cell transplantation (HSCT) generally have a poor outcome. We retrospectively studied whether the risk-prediction stratification systems commonly used for patients admitted to the ICU, that is, the Acute Physiology and Chronic Health Evaluation (APACHE) II and APACHE III systems, could be useful for identifying patients who should receive intensive care earlier. We reviewed the medical records of 210 patients who underwent allogeneic HSCT and found that 18 (8.6%) had been admitted to the ICU for acute respiratory failure (n=9), acute renal failure (n=7), and septic shock (n=2). The median APACHE II and III scores were, respectively, 16 (10-27) and 55 (22-87) at the onset of complications and 26 (15-43) and 101 (65-157) upon admission to the ICU. Thus, both the APACHE II and APACHE III scores at ICU admission were higher than those at the onset of complications (P <0.0001). Seventeen patients (94%) subsequently died, with a median ICU stay of 7.5 days (1-51 days), as a result of multiorgan failure (n=14), respiratory failure (n=2), and septic shock (n=1). The APACHE II and III scores of the sole surviving patient were, respectively, 21 and 71 at the onset and 24 and 86 upon transfer to the ICU. Thus, the APACHE scores in this study were lower than those reported for other surgical or medical patients treated in the ICU, despite their uniform poor prognosis. Although nine patients had developed grade III to IV acute graft-versus-host disease, which is the most common cause of morbidity and mortality after allogeneic HSCT, this was not fully evaluated in the current scoring systems. Application of these systems to HSCT will require adequate modification, with particular attention to organ dysfunction secondary to graft-versus-host disease.  相似文献   
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