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51.
PURPOSE: The purpose of this study was to prospectively evaluate the usefulness of contrast-enhanced power Doppler sonography (PDUS) using a microbubble echo-enhancing agent in differentiating between malignant and benign small breast lesions. PATIENTS AND METHODS: Between July 1, 2000, and September 30, 2001, we performed gray-scale sonographic examination of patients in whom diagnostic sonography or screening mammography had revealed solid breast lesions measuring less than 2 cm in the largest dimension. The patients were then examined on PDUS before and after injection of a microbubble contrast agent. The sonographic findings for all 3 techniques, as well as the morphologic features of the Doppler signals for each patient before and after injection of the contrast agent on PDUS, were independently assessed. Each lesion was classified as "benign" or "malignant" on the basis of specific criteria for sonographic interpretation. A hemodynamic study was performed in which time-transit profiles of the Doppler signals on contrast-enhanced PDUS were generated using a computer-assisted program, and the results for each patient were compared with the findings of a histopathologic examination of surgical specimens. RESULTS: Thirty-six patients (35 women and 1 man) with a mean age of 43.5 years (range, 18-69 years) were evaluated. The tumors ranged from 4 to 19 mm in the largest dimension. Histopathologic examination revealed that 19 tumors were benign and 17 were malignant. For morphologic diagnosis of the malignant lesions, the sensitivity of gray-scale sonography was 100%, compared with 29% for PDUS without contrast enhancement. The specificity of gray-scale sonography was 47%, compared with 74% for PDUS without contrast enhancement. Contrast-enhanced PDUS had a sensitivity of 71% and a specificity of 58%. The diagnostic accuracy was 72% for gray-scale sonography, 53% for PDUS without contrast enhancement, and 64% for contrast-enhanced PDUS. The time-transit profiles of the hemodynamic study did not reveal a statistically significant difference in the accuracy rates of contrast-enhanced PDUS between benign and malignant breast lesions. CONCLUSIONS: Compared with PDUS without contrast enhancement, contrast-enhanced PDUS provides better visualization of the morphology of vascular Doppler signals that is characteristic of malignancy and therefore has a higher sensitivity and diagnostic accuracy, albeit a lower specificity. In differentiating between benign and malignant small breast lesions, contrast-enhanced PDUS can be helpful when used with gray-scale sonography and PDUS without contrast enhancement.  相似文献   
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Background

The aim was to examine the numbers of hours worked and patient visits provided by age and gender of dentists in Australia, and compare with previous estimates to describe trends.

Methods

Data were collected from a random sample (N = 2961) of Australian dentists. Private sector dentists working in clinical practise were included in the analysis.

Results

The response rate was 49% (N = 1345 dentists). Hours per year worked and number of patient visits per year were lower for dentists aged 65 years and older compared with younger dentists, and were higher for male compared with female dentists aged 35–45 to 55–64 years. Hours per year worked were lower in 2013–2014 than reported in 2009–2010, but the number of patient visits in 2013–2014 was similar to the previously reported estimate from 2009–2010.

Conclusions

Hours worked and visits provided were only lower among older dentists aged 65 years or more. Male dentists tend to work more hours per year and provide more patient visits per year than female dentists. Over the last decade, Australian dentists maintained a stable output of visits per year despite a trend towards fewer hours worked per year.  相似文献   
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Private health insurance plays a key role in financing dental care in Australia. Having private dental insurance has been associated with higher levels of access to dental care, visiting for a check‐up and receiving a favourable pattern of services. Associations with better oral health have also been reported. In the absence of any existing review, this paper aims to systematically review the relationship between dental insurance and dental service use and/or oral health outcomes in Australia. A systematic search of online databases and subsequent sifting resulted in 36 publications, 33 of which were cross sectional and three cohort analyses. Dental service outcomes were more commonly reported than oral health outcomes. There was considerable heterogeneity in the outcome measures reported, for both service use and health outcomes. Overall, the majority of the evidence was from cross sectional studies and few studies reported analyses adjusted for confounding factors. The consolidated evidence points towards a positive association between dental insurance and dental visiting. Dentally insured adults are likely to have more regular access to dental care and have a more favourable pattern of service use than the uninsured. However, evidence of associations between dental insurance and oral health are mixed.  相似文献   
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Objective

To evaluate the clinical utility of the meniscal extrusion transverse ratio of the medial meniscus in the diagnosis of meniscal root tear compared with the gold standard of arthroscopic diagnosis.

Methods

This retrospective study sample included 32 males and 35 females who underwent MRI at our institution. There were 24 meniscal root tear cases. The control groups were 18 cases of medial meniscal tears without root tears and 25 cases of negative meniscal findings on arthroscopy. Meniscal extrusion (L) and maximal transverse lengths (T) of the medial meniscus were measured, and L/T ratios were calculated. These results were correlated with arthroscopic findings and analysed statistically. With arthroscopic findings used as the standard of reference, the sensitivity and specificity of 10%, 11% and 12% extrusion thresholds, and 3 mm of medial meniscal extrusion (MME) as diagnostic thresholds, were calculated.

Results

The mean length of the meniscal extrusions of meniscal root tears was twice as long as the control group. The mean L/T ratio of the meniscal root tears was approximately 13%, while those of the control groups were 5%. The differences in the L and L/T between the meniscal root tears and normal and meniscal root tears and other meniscal tears were statistically significant (p<0.001), but those between normal and other meniscal tears were not. The best diagnostic discrimination was achieved using an extrusion ratio threshold of 10% (79% sensitivity, 86% specificity). The 3 mm of MME threshold demonstrated high specificity (98%), but not high sensitivity (54%).

Conclusion

The mean L/T ratio of the meniscal root tears was approximately 13% and was statistically significant. The best diagnostic discrimination was achieved using an extrusion ratio threshold of 10%.

Advances in knowledge

The use of the L/T ratio in combination with MME can be a useful method for evaluating medial meniscal root tears.The meniscal roots are the sites where the knee meniscus attaches to the central tibial plateau [1]. In many cases, a meniscal root tear is not prominent on a single MRI image as the structures follow oblique courses. Medial meniscal extrusion (MME) is a significant medial displacement of the medial meniscus with respect to the central margin of the medial tibial plateau and is closely associated with medial meniscal root tears (MMR) [2]. The meniscus is considered “extruded” when it extends beyond the tibial margin; this results from disruption of collagen fibres within the meniscus that provide hoop strength [3]. The critical length of extrusion is approximately 3 mm [4-5]. There is some uncertainty regarding the length of the extrusion because the transverse diameter of the medial meniscus varies with age and individual; uniform length criteria can be replaced with length ratios. The current study was performed to evaluate the clinical utility of the meniscal extrusion transverse ratio of the medial meniscus in the diagnosis of the meniscal root tears as compared with the gold standard of arthroscopic diagnosis.  相似文献   
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