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71.
Mauro Gentile Alessandro De Vito Cristiano Azzini Carmine Tamborino Ilaria Casetta 《Ultrasound in medicine & biology》2014,40(11):2637-2641
Contrast-transcranial Doppler and contrast-transcranial color-coded duplex sonography (c-TCCD) have been reported to have high sensitivity in detecting patent foramen ovale as compared with transesophageal echocardiography. An international consensus meeting (Jauss and Zanette 2000) recommended that the contrast agent for right-to left-shunt (RLS) detection using contrast-transcranial Doppler be prepared by mixing 9 mL of isotonic saline solution and 1 mL of air. The aim of our study was to determine whether adding blood to the contrast agent results in improved detection of RLS. We enrolled all consecutive patients admitted to our neurosonology laboratory for RLS diagnosis. For each patient, we performed c-TCCD both at rest and during the Valsalva maneuver using two different contrast agents: ANSs (1 mL of air mixed with 9 mL of normal saline) and ANSHBs (1 mL of air mixed with 8 mL of normal saline and 1 mL of the patient's blood). To classify RLS, we used a four-level visual categorization: (i) no occurrence of micro-embolic signals; (ii) grade I, 1–10 signals; (iii) grade II, >10 signals but no curtain; grade III, curtain pattern. We included 80 patients, 33 men and 47 women. RLS was detected in 18.8% at rest and in 35% during the Valsalva maneuver using ANSs, and in 31.3% and in 46.3% using ANSHBs, respectively (p < 0.0001). There was a statistically significant increase in the number of micro-embolic signals with the use of ANSHBs. The use of blood mixed with saline solution and air as a c-TCCD contrast agent produced an increase in positive tests and a higher grade of RLS compared with normal saline and air alone, either with or without the Valsalva maneuver. 相似文献
72.
J.-M. Krzesinski 《Acta chirurgica Belgica》2013,113(3):159-166
Renovascular hypertension is a clinical situation characterized by high blood pressure in the presence of renal ischemia mainly related to atherosclerotic or fibromuscular dysplasic narrowing of the renal artery (ies). This diagnosis is often “a posteriori” validated, because the discovery of a significant renal artery stenosis is not obligatory responsible of the blood pressure elevation.This article proposes a diagnostic strategy for exploring patient with this suspected secondary cause of hypertension before proposing an invasive approach (intra-arterial angiography) possibly followed by a revascularization. However, the methods for exploring such population are mainly based on patient characteristics and local expertise and habits. These must thus be individualized. First, clinical symptoms or signs frequently associated with hypertension and renal artery stenosis must be searched. If present, a non invasive and functional exploration of the renal arteries is to be proposed (Captopril radioisotope renography, colour duplex sonography) followed by magnetic resonance angiography or spiral computer tomography angiography if the clinical suspicion index is moderate or high. If this is very high, an intraarterial arteriography could immediately be performed if not too dangerous. On the opposite site, if the clinical index is low, it is recommended to follow clinically and to treat risk factors. 相似文献
73.
Jacinta E. Browne Louise M. Cannon Ronan McDermott Max Ryan Andrew J. Fagan 《Ultrasound in medicine & biology》2017,43(11):2733-2740
A device for the training and quantitative assessment of the competency of trainee radiologists in the technically challenging area of breast sonography was developed and evaluated. Currently, suitable commercially available devices are lacking, and there is a growing realization that the reliance on direct exposure to patients for learning may not represent best practice from either the trainees' or patients' perspective. Three devices (PI, PII and PIII) were designed to produce very realistic sonographic images of breast morphology with a range of embedded pathologies. The pilot evaluation used a case study research design to evaluate the role of the anthropomorphic breast sonography training device in training and assessment in a clinical environment. Through the case study, it was possible to evaluate the process and relationships when using this type of training intervention for a small group of radiology resident trainees. The investigation involved a baseline assessment of trainees' (n = 4) ability to detect and characterize all lesions in PI, followed by a 4-wk training period on PII and a post-training assessment using PIII. The evaluation revealed an improvement of 30% ± 8% in the trainee's performance from pre- to post-training. It was expected that the performance of the trainees would improve as the training phantom described in this study aligns with the learning theory of constructivism and fits the ideal specifications of a medical training device in terms of its realism and facilitation of self-directed learning and deliberate practice of the trainees. The device provides a useful platform upon which training and assessment can be facilitated. 相似文献
74.
Hans P. Van Lancker MD Paul A. Martineau MD Viviane Khoury MD 《Journal of ultrasound in medicine》2013,32(9):1653-1657
Engaging Hill‐Sachs lesions can be a factor predictive of recurrent anterior shoulder instability, yet no method has been recognized as an effective means to predict engagement. We evaluated the ability of sonography to identify engaging Hill‐Sachs lesions by using a transaxillary approach and dynamic scanning. In patients with engaging lesions, there was an abrupt change in the contour of the humeral head when the shoulder was in 90° of abduction and 90° of external rotation. Sonography therefore has the potential to be a useful preoperative tool in determining which patients may benefit from a surgical repair that also addresses Hill‐Sachs lesions. 相似文献
75.
76.
Liang Wang MD Yu Xia MD Yu-Xin Jiang MD Qing Dai MD Xiao-Yi Li MD 《Journal of ultrasound in medicine》2012,31(11):1767-1775
77.
78.
79.
Sodhi KS Sidhu R Gulati M Saxena A Suri S Chawla Y 《Journal of gastroenterology and hepatology》2005,20(10):1488-1493
Background: The purpose of the present study was to compare iissue harmonic imaging (THI) and conventional sonography in focal hepatic lesions. Methods: Fifty patients with focal hepatic lesions were enrolled for study. Conventional grayscale and THI was performed in all the patients and two sets of images of the lesions were recorded (one each for THI and conventional) and assessed for fluid–solid differentiation, detail and overall image quality. These images were compared with conventional sonographic images and graded better, same or worse as per the case. Lesions were confirmed by fine‐needle aspiration cytology (FNAC)/surgery/other modalities such as computed tomography (CT) or magnetic resonance imaging (MRI). Results: Out of 50 patients with focal hepatic lesions, 21 patients had metastatic lesions (two single; 19 multiple) five patients had hepatocellular carcinoma (HCC), five patients had hydatid cysts, nine had simple hepatic cyst whereas five patients had liver abscess, three had focal fatty infiltration; and lymphoma and hemangioma were seen in one patient each. The first observer ranked THI better than standard sonography in 40 patients (80%) for fluid–solid differentiation, in 38 (76%) for detail and in 39 (78%) for overall image quality. The second observer ranked THI better than standard sonography in 39 patients (78%) for fluid–solid differentiation, in 40 (80%) for detail and in 42 (84%) for overall image quality. Tissue harmonic imaging provided additional information in eight patients (16%) and resulted in treatment alteration in three patients (6%). Conclusion: Tissue harmonic imaging was significantly better than conventional sonography for fluid–solid differentiation, detail and total image quality in focal hepatic lesions, especially in obese patients and patients with poor acoustic window. 相似文献
80.
We present a retrospective review of 8 patients (6 women and 2 men, with an age range of 46–80 years; mean age, 60.2 years) in whom sonography was used to diagnose a calcaneal stress fracture. Sonography was performed because of a clinical suspicion of soft tissue injuries. Two patients were first assessed by standard radiography; for the remaining patients, sonography was the first imaging technique used. Patients were subsequently examined by magnetic resonance imaging, except for 1 patient in whom the diagnosis was made only on a clinical‐sonographic correlation. On sonography, there was thickening of the periosteum and subcutaneous edema in all patients; a calcified bone callus was evident in none of the 8 patients. Cortical irregularities were found in 6 of 8 patients. Color Doppler imaging showed local hypervascular changes of the periosteum in all patients. Sonography, together with clinical findings, can be used to diagnose a calcaneal stress fracture. We suggest that sonologists should include a calcaneal stress fracture in their differential diagnosis in cases of mechanical hind foot pain. They must also include, as a part of every sonographic examination of the ankle, an examination of the calcaneus and be aware of the sonographic appearance of stress fractures. If the diagnosis is still uncertain after the sonographic examination, magnetic resonance imaging should be prescribed. 相似文献