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81.
We report a young patient with post traumatic acquired thoracic aortic coarctation in whom three‐dimensional transthoracic echocardiography (3DTTE) demonstrated incremental value over two‐dimensional transthoracic echocardiography (2DTTE). 3DTTE showed (1) en face views of the obstruction site that showed a markedly narrowed, roughly circular orifice measuring 0.33 cm2 in area, (2) echogenic tissue encroaching on the graft lumen consistent with fibrosis/thrombus, and (3) no graft protrusion into the aortic lumen, only hypermobility of the medial portion of the graft. These important findings were not detected by 2DTTE. (Echocardiography 2010;27:470‐472)  相似文献   
82.
We studied 31 patients with prosthetic valves (PVs) using two‐dimensional and three‐dimensional transthorathic echocardiography (2DTTE and 3DTTE, respectively) in order to determine whether 3DTTE provides an incremental value on top of 2DTTE in the evaluation of these patients. With 3DTTE both leaflets of the St. Jude mechanical PV can be visualized simultaneously, thereby increasing the diagnostic confidence in excluding valvular abnormalities and overcoming the well‐known limitations of 2DTTE in the examination of PVs, which heavily relies on Doppler. Three‐dimensional transthorathic echocardiography provides a more comprehensive evaluation of PV regurgitation than 2DTTE with its ability to more precisely quantify PV regurgitation, in determining the mechanism causing regurgitation, and in localizing the regurgitant defect. Furthermore, 3DTTE is superior in identifying, quantifying, and localizing PV thrombi and vegetations, in addition to the unique feature of providing a look inside mass lesions by serial sectioning. These preliminary results suggest the superiority of 3DTTE over 2DTTE in the evaluation of PVs and that it provides incremental knowledge to the echocardiographer. (ECHOCARDIOGRAPHY, Volume 26, November 2009)  相似文献   
83.
Multicenter evaluation of SonoVue for improved endocardial border delineation   总被引:10,自引:0,他引:10  
OBJECTIVES: Two multicenter studies were conducted to evaluate the safety and efficacy of SonoVue as a contrast agent for enhanced left ventricular endocardial border delineation (LVEBD), and to compare the efficacy of SonoVue and Albunex in adult patients with a suboptimal, nonenhanced echocardiogram. BACKGROUND: The use of contrast to enhance echocardiographic assessment of LVEBD is well-established. SonoVue is a new microbubble contrast agent that contains sulfur hexafluoride. METHODS: Patients were randomized to receive four injections of SonoVue (0.5, 1, 2, and 4 ml), or two injections of Albunex and two injections of hand-agitated saline (0.08 and 0.22 ml/kg). Echocardiographic images were evaluated at the study centers and by four blinded, offsite reviewers for degree of left ventricle opacification (LVO), duration of contrast enhancement, and LVEBD. RESULTS: LVO scores were significantly higher for all doses of SonoVue. Patients with complete LVO ranged from 34%-87% for SonoVue and from 0%-16% for Albunex. The mean duration of useful contrast effect ranged from 0.8-4.1 minutes for SonoVue and < 15 seconds for Albunex. Mean increases in LVEBD scores ranged from 3.8-18.2 for SonoVue and 0.1-4.3 for Albunex. SonoVue (cumulative 7.5 ml dose) was well-tolerated, with a safety profile similar to that observed in the control group. CONCLUSIONS: SonoVue is superior to Albunex for improving visualization of endocardial borders in patients with suboptimal noncontrast echocardiograms. Optimal increases in LVEBD, LVO, and duration of useful contrast effect were observed at the 2.0 ml dose of SonoVue.  相似文献   
84.
We describe a transesophageal technique for identifying the origin and precervical course of the right vertebral artery with the probe positioned in the upper esophagus. The technique was successful in 9 of 11 patients in whom it was attempted.  相似文献   
85.
86.
Ten confirmed cases of invasive aspergillosis (IA) in cancer patients were analysed retrospectively. Eight were pulmonary, one was sinonasal and one was cutaneous. The majority of patients had haematological malignancies (7), the remaining three were cases of solid tumours. Fever was present in all 10 cases. Cough and lung signs were present in all eight cases of invasive pulmonary aspergillosis. Haemoptysis was encountered in three of nine cases of pulmonary and sinonasal aspergillosis. Mortality was low (2%). While corticosteroids, antibiotics and anticancer chemotherapy/radiotherapy were factors predisposing the patients to IA, neutropenia was perhaps responsible for their mortality. Seven of the patients had other associated pathogens isolated in culture in addition to Aspergillus spp. Aspergillus fumigatus was the predominant species, followed by A. flavus, A. glaucus, A. nidulans and A. niger. Direct microscopic examination (in six of seven cases) and culture (six of seven cases) correlated well with radiographic and clinical findings in cases with lung involvement. Serology for anti-Aspergillus antibodies performed by gel diffusion precipitin test was positive in one case of sinonasal aspergillosis, wherein only one precipitin band was observed. Correlation of clinical symptoms, consistent radiographic findings and microbiological work-up (the latter including a triad of direct microscopy, culture and serology) are required to arrive at a diagnosis of IA, especially where histology cannot form the mainstay of diagnosis.  相似文献   
87.
88.
目的探讨原发性甲状腺功能亢进的手术治疗。方法回顾性分析33例原发性甲状腺功能亢进症患者手术治疗的临床资料,行双侧近全切除30例,一侧全切加对侧次全切2例,双侧全切除1例。结果本组无死亡病例,双侧全切除患者术后发生永久性喉返神经瘫痪伴甲状旁腺功能低下。所有病例经随访2-18月,无1例复发,5例出现甲状腺功能减退,采用甲状腺素替代治疗效果满意。结论手术是治疗原发性甲状腺功能亢进的安全有效办法,推荐术式为甲状腺近全切除术,强调围手术期处理,熟练掌握手术技巧可防止手术并发症。  相似文献   
89.
90.
Effects of an alkylating anticancer drug, cyclophosphamide (Cp), on 23Na signal intensity (23Na SI) and water apparent diffusion coefficient (ADC) were examined in subcutaneously-implanted radiation-induced fibrosarcoma (RIF-1) tumors by 23Na and 1H magnetic resonance imaging (MRI). MRI experiments were performed on untreated control (n = 5) and Cp-treated (n = 6) C3H mice, once before Cp injection (300 mg/kg) then daily for 3 days after treatment. Tumor volumes were significantly lower in treated animals 2 and 3 days posttreatment. At the same time points, in vivo MRI experiments showed an increase in both 23Na SI and water ADC in treated tumors, whereas control tumors did not show any significant changes. The correlation between 23Na SI and water ADC changes was dramatically increased in the Cp-treated group, suggesting that the observed increases in 23Na SI and water ADC were caused by the same mechanism. Histologic sections showed decreased cell density in the regions of increased 23Na and water ADC SI. Destructive chemical analysis showed that Cp treatment increased the relative extracellular space and tumor [Na+]. We conclude that the changes in water ADC and 23Na SI were largely due to an increase in extracellular space. 23Na MRI and 1H water ADC measurements may provide valuable noninvasive techniques for monitoring chemotherapeutic responses.  相似文献   
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