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Yuanyuan Feng Hannah McGowan Azin Semsar Hamid R. Zahiri Ivan M. George Timothy Turner Adrian Park Andrea Kleinsmith Helena M. Mentis 《International journal of computer assisted radiology and surgery》2018,13(9):1463-1472
Purpose
To assess a virtual pointer in supporting surgical trainees’ development of professional vision in laparoscopic surgery.Methods
We developed a virtual pointing and telestration system utilizing the Microsoft Kinect movement sensor as an overlay for any imagine system. Training with the application was compared to a standard condition, i.e., verbal instruction with un-mediated gestures, in a laparoscopic training environment. Seven trainees performed four simulated laparoscopic tasks guided by an experienced surgeon as the trainer. Trainee performance was subjectively assessed by the trainee and trainer, and objectively measured by number of errors, time to task completion, and economy of movement.Results
No significant differences in errors and time to task completion were obtained between virtual pointer and standard conditions. Economy of movement in the non-dominant hand was significantly improved when using virtual pointer (\(p = 0.012\)). The trainers perceived a significant improvement in trainee performance in virtual pointer condition (\(p < 0.001\)), while the trainees perceived no difference. The trainers’ perception of economy of movement was similar between the two conditions in the initial three runs and became significantly improved in virtual pointer condition in the fourth run (\(p = 0.017\)).Conclusions
Results show that the virtual pointer system improves the trainer’s perception of trainee’s performance and this is reflected in the objective performance measures in the third and fourth training runs. The benefit of a virtual pointing and telestration system may be perceived by the trainers early on in training, but this is not evident in objective trainee performance until further mastery has been attained. In addition, the performance improvement of economy of motion specifically shows that the virtual pointer improves the adoption of professional vision— improved ability to see and use laparoscopic video results in more direct instrument movement.3.
Maria Elissavet Metska Azin Parsa Irene Helena Adriana Aartman Paul Rudolf Wesselink Ahmet Rifat Ozok 《Journal of endodontics》2013
Introduction
Cone-beam computed tomography (CBCT) allows us to assess in 3 dimensions the location and size of periapical radiolucencies. We aimed to assess by CBCT scans the volumetric changes of periapical radiolucencies in endodontically treated teeth 1 year after orthograde retreatment.Methods
Forty-five root-filled teeth with persistent apical periodontitis requiring endodontic orthograde retreatment from 37 individuals were included in the study. The research protocol was approved by the VU University Medical Center Amsterdam ethics committee (2007/265), and the participants signed a letter of consent. We made 2 CBCT scans for every patient, the first one before retreatment and the second one a year later. Two observers measured independently the volume of radiolucencies on CBCT images by using the AMIRA software. The intraclass correlation coefficient was used to evaluate interobserver agreement, and the Wilcoxon signed rank test was used to assess pretreatment and post-treatment volume size.Results
The intraclass correlation coefficients were 0.994 and 0.998 for the scans before retreatment and 1 year after, respectively. The recall rate was 78% for the teeth and 73% for the patients. The volumetric change in periapical radiolucencies 1 year after retreatment was statistically significant (z = −3.112, P < .005). The volume of periapical radiolucencies reduced in 20 teeth (57%), remained unchanged in 8 (23%), and increased in 7 (20%).Conclusions
One year after endodontic orthograde retreatment, the volume of periapical radiolucencies reduced significantly in 57% of the teeth. 相似文献4.
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Jameela Abdulaziz Kari Sherif El-Desoky Youssef Farag Hisham Mosli Abdul-Malik Altyieb Ahmad Al Sayad Othman Radawi Hosam Ghabra Faten Basnawi Ohood Bahrawi Ajay Singh Hassan Farsi 《Pediatric nephrology (Berlin, Germany)》2013,28(6):927-931
Background
Posterior urethral valves (PUV) are a common cause of end-stage renal failure in childhood. Our aim was to describe a cohort of patients with PUV and to investigate the predictors of renal impairment.Methods
We performed a retrospective chart review of children with PUV who were followed at King Abdulaziz University hospital between 2002 and 2011.Results
The cohort comprised 68 boys. There was a significant difference in the duration of follow-up (p?=?0.024), nadir serum creatinine (p?<?0.001), and last known serum creatinine level (p?=?0.001) between the patients with and without renal impairment. The duration of follow-up appeared to be a significant predictor for serum creatinine doubling (p?=?0.003; odds ratio, 1.8). There was no difference in the age of presentation, age at the time of the study, and first or last serum creatinine between children who initially had vesicostomy and children who had ablation.Conclusions
Ablation of PUV or vesicostomy did not influence kidney function in our study cohort. Children with a normal nadir serum creatinine who presented early had a better outcome. 相似文献6.
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Beatriz Bonadio Aoki Dayana Fram M?nica Taminato Ruth Ester Sayad Batista Angélica Belasco Dulce Aparecida Barbosa 《Revista latino-americana de enfermagem》2014,22(4):637-644
OBJECTIVES:
to assess renal function in elderly patients undergoing contrast-enhanced computed tomography and identify the preventive measures of acute kidney injury in the period before and after the examination.METHOD:
longitudinal cohort study conducted at the Federal University of São Paulo Hospital, from March 2011 to March 2013. All hospitalized elderly, of both sexes, aged 60 years and above, who performed the examination, were included (n=93). We collected sociodemographic data, data related to the examination and to the care provided, and creatinine values prior and post exam.RESULTS:
an alteration in renal function was observed in 51 patients (54%) with a statistically significant increase of creatinine values (p<0.04), and two patients (4.0%) required hemodialysis.CONCLUSION:
There is an urgent need for protocols prior to and post contrast-enhanced examination in the elderly, and other studies to verify the prognosis of this population. 相似文献9.
Maria Elissavet Metska Vania May Ling Liem Azin Parsa Jan Harm Koolstra Paul Rudolf Wesselink Ahmet Rifat Ozok 《Journal of endodontics》2014
Introduction
The primary aim of this study was to compare the precision of root canal length determination on cone-beam computed tomographic (CBCT) scans and periapical radiographs (PAs) with the actual root canal length. The secondary aim was to examine the influence of tooth type on root canal length measurements as assessed on CBCT scans and PAs.Methods
In total, 40 root canals of 33 teeth (molars, premolars, canines, and incisors) out of 5 dentate maxillas of human cadavers were included. Root canal length measurement was performed by a consensus panel (2 examiners) on CBCT scans (3D Accuitomo 170; J Morita, Kyoto, Japan) and digital PAs. After straight-line access opening, a #15 file was fixated in every root canal at the length measured on CBCT scans. All teeth were extracted, and the root canal containing the file was uncovered. Measurements made on images taken with a digital camera (AxioCam; Carl Zeiss, Sliedrecht, The Netherlands) linked to a stereozoom microscope (Stemi SV6, Carl Zeiss) were used as the actual root canal length.Results
When all roots were examined together, it was not clear which method is better for all types of teeth. For root canals of anterior teeth, there was no significant difference between the 2 methods. For root canals of posterior teeth, CBCT images gave results significantly closer to the actual root canal length in comparison with PAs (t value = −1.96; critical value is 1.74 with a significance level of 0.05).Conclusions
Root canal length measurements of posterior maxillary teeth were more accurate when assessed by CBCT images than PAs. 相似文献10.