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Purpose

To compare the position and orientation accuracy between using one 6-degree of freedom (DOF) electromagnetic (EM) sensor, or the position information of three 5DOF sensors within the scope of tumor tracking.

Methods

The position accuracy of Northern Digital Inc Aurora 5DOF and 6DOF sensors was determined for a table-top field generator (TTFG) up to a distance of 52 cm. For each sensor 716 positions were measured for 10 s at 15 Hz. Orientation accuracy was determined for each of the orthogonal axis at the TTFG distances of 17, 27, 37 and 47 cm. For the 6DOF sensors, orientation was determined for sensors in-line with the orientation axis, and perpendicular. 5DOF orientation accuracy was determined for a theoretical 4 cm tumor. An optical tracking system was used as reference.

Results

Position RMSE and jitter were comparable between the sensors and increasing with distance. Jitter was within 0.1 cm SD within 45 cm distance to the TTFG. Position RMSE was approximately 0.1 cm up to 32 cm distance, increasing to 0.4 cm at 52 cm distance. Orientation accuracy of the 6DOF sensor was within 1\(^\circ \), except when the sensor was in-line with the rotation axis perpendicular to the TTFG plane (4\(^\circ \) errors at 47 cm). Orientation accuracy using 5DOF positions was within 1\(^\circ \) up to 37 cm and 2\(^\circ \) at 47 cm.

Conclusions

The position and orientation accuracy of a 6DOF sensor was comparable with a sensor configuration consisting of three 5DOF sensors. To achieve tracking accuracy within 1 mm and 1\(^\circ \), the distance to the TTFG should be limited to approximately 30 cm.
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Medical treatment of patients inherently entails the risk of undesired complication or side effects. It is essential to inform the patient about the expected outcomes, but also the possible undesired outcomes. The patients preference and values regarding the potential outcomes should be involved in the decision making process. Even though many orthopaedic surgeons are positive towards shared decision-making, it is minimally introduced in the orthopaedic daily practice and decision-making is still mostly physician based. Decision aids are designed to support the physician and patient in the shared- decision-making process. By using decision aids, patients can learn more about their condition and treatment options in advance to the decision-making. This will reduce decisional conflict and improve participation and satisfaction.  相似文献   
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Objective

To examine the potential of a questionnaire (CQI ‘R-ICU’) to measure the quality of care from the perspective of relatives in the Intensive Care Unit (ICU).

Methods

A quantitative survey study has been undertaken to explore the psychometric properties of the instrument, which was sent to 282 relatives of ICU patients from the Erasmus MC, an academic hospital in Rotterdam, the Netherlands. Factor-analyses were performed to explore the underlying theoretical structure.

Results

Survey data from 211 relatives (response rate 78%) were used for the analysis. The overall reliability of the questionnaire was sufficiently high; two of the four underlying factors, namely ‘Communication’ and ‘Involvement’, were significant predictors. Two specific aspects of care that needed the most improvement were missing information about meals and offering an ICU diary. There is a significant difference in mean communication with nurses among the four wards in Erasmus MC.

Conclusions

The CQI ‘R-ICU’ seems to be a valid, reliable and usable instrument. The theoretical fundament appears to be related to communication.

Practice implications

The newly developed instrument can be used to provide feedback to health care professionals and policy makers in order to evaluate quality improvement projects with regard to relatives in the ICU.  相似文献   
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Background and objectives

Breast conserving surgery (BCS) can be challenging for large regions of ductal carcinoma in situ (DCIS), resulting in high rates of positive resection margins. Radioactive seed localization (RSL) using multiple radioactive iodine (125I) seeds can be used to bracket extensive DCIS (eDCIS). The goal of this study was to retrospectively compare the use of a single or multiple 125I seeds in RSL to enable BCS in patients with eDCIS.

Methods

All patients with eDCIS (area of ≥3.0 cm) who underwent either single or multiple-seed RSL between January 2008 and December 2016 were included. Patient, tumor and surgery characteristics were compared between both groups. Primary outcome measures were positive resection margin and re-operation rates.

Results

Respectively 48 and 58 patients with eDCIS underwent single- and multiple-seed RSL and subsequent BCS. The rate of positive resection margin (focal and more than focal) with single-seed RSL was 47.9%, compared to 29.3% with multiple-seed RSL (p = 0.06). The re-operation rate was 39.6% with single-seed RSL and 20.7% in the multiple-seed RSL group (p = 0.05).

Conclusion

Multiple-seed RSL enables bracketing of large areas of DCIS, with the potential to decrease the high rate of positive resection margins in this patient group.  相似文献   
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This study investigates the relationship between blood group and waiting time until transplantation or death on the waiting list. All patients listed for liver transplantation in the Netherlands between 15 December 2006 and 31 December 2012, were included. Study variables were gender, age, year of listing, diagnosis, previous transplantations, blood group, urgency, and MELD score. Using a competing risks analysis, separate cumulative incidence curves were constructed for death on the waiting list and transplantation and used to evaluate outcomes.In 517 listings, the mean death rate per 100 patient‐years was 10.4. A total of 375 (72.5% of all listings) were transplanted. Of all transplantations, 352 (93.9%) were ABO‐identical and 23 (6.1%) ABO‐compatible. The 5‐year cumulative incidence of death was 11.2% (SE 1.4%), and of transplantation 72.5% (SE 2.0%). Patient blood group had no multivariate significant impact on the hazard of dying on the waiting list nor on transplantation. Age, MELD score, and urgency status were significantly related to the death on the waiting list and transplantation. More recent listing had higher probability of being transplanted. In the MELD era, patient blood group status does not have a significant impact on liver transplant waiting list mortality nor on waiting time for transplantation.  相似文献   
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