Background and Purpose: To perform a retrospective in vivo dosimetry study of 129 total body irradiation (TBI) on leukemia and bone marrow transplant patients treated in our clinic from 2008 to 2011 and to find out if...Background and Purpose: To perform a retrospective in vivo dosimetry study of 129 total body irradiation (TBI) on leukemia and bone marrow transplant patients treated in our clinic from 2008 to 2011 and to find out if there is any indication of the necessity of developing a new efficient TBI approach. Materials and Methods: The in vivo dosimetry data of 129 patients treated with TBI between 2008 and 2011 were retrieved from the database and analyzed. These patients were mostly treated with the regime of a single fraction or 6 fractions with some exceptions of 8-fraction or 2-fraction treatments depending on the protocols that were applied. For every fraction of treatment, 10 pairs of diode dosimeters were used to monitor the doses to the midline of head, neck, arms, mediastinum, left lung, right lung, umbilicus, thigh, knee, and ankle for both AP and PA fields. The doses to the midline of the above body parts were considered to be the average of the AP and PA readings of each diode pair. Dose deviation from the prescribed value for each body part was studied by plotting the histogram of the frequency versus deviation and comparing this with the dose delivered to the midline of the umbilicus to where the dose was prescribed. The correlation of dose deviation to body part thickness was also studied. By studying the dose deviations, we can find the uniformity of general dose distributions for conventional TBI treatments. Results: The retrospective dosimetry study of the 129 TBI patient treatments indicates that for most of the patients treated in our clinic, the doses received by different body parts monitored with in vivo dosimetry were within the window of 10% difference from the prescribed dose. The inhomogeneity of dose on different body parts could be manually improved by using compensators, but the method is cumbersome and time consuming. The dose deviation in many histograms ranging from about ?10% to 10% indicates some incongruity of dose distribution. This could be due to the method of using lead compensato展开更多
Operating Theatre is the centre of the hospital management＇s efforts. It constitutes the most expensive sector with more than 10% of the intended operating budget of the hospital. To reduce the costs while maintainin...Operating Theatre is the centre of the hospital management＇s efforts. It constitutes the most expensive sector with more than 10% of the intended operating budget of the hospital. To reduce the costs while maintaining a good quality of care, one of the solutions is to improve the existent planning and scheduling methods by improving the services and surgical specialty coordination or finding the best estimation of surgical case durations. The other solution is to construct an effective surgical case plan and schedule. The operating theatre planning and scheduling is the two important steps, which aim to make a surgical case programming with an objective of obtaining a realizable and efficient surgical case schedule. This paper focuses on the first step, the operating theatre planning problem. Two planning methods are introduced and compared. Real data of a Belgian university hospital ＂Tivoli＂ are used for the experiments.展开更多
The paper discusses an extended entropy model for the prediction of trip amount and provides a method to solve it, called the simple block iterative algorithm, from the point of view of the system of nonlinear equatio...The paper discusses an extended entropy model for the prediction of trip amount and provides a method to solve it, called the simple block iterative algorithm, from the point of view of the system of nonlinear equations. Because the algorithm gives consideration to the characteristic of the model, it has better effect in our practice. The paper also studies the existence and uniqueness of the solution and convergence of the algorithm.展开更多
文摘Background and Purpose: To perform a retrospective in vivo dosimetry study of 129 total body irradiation (TBI) on leukemia and bone marrow transplant patients treated in our clinic from 2008 to 2011 and to find out if there is any indication of the necessity of developing a new efficient TBI approach. Materials and Methods: The in vivo dosimetry data of 129 patients treated with TBI between 2008 and 2011 were retrieved from the database and analyzed. These patients were mostly treated with the regime of a single fraction or 6 fractions with some exceptions of 8-fraction or 2-fraction treatments depending on the protocols that were applied. For every fraction of treatment, 10 pairs of diode dosimeters were used to monitor the doses to the midline of head, neck, arms, mediastinum, left lung, right lung, umbilicus, thigh, knee, and ankle for both AP and PA fields. The doses to the midline of the above body parts were considered to be the average of the AP and PA readings of each diode pair. Dose deviation from the prescribed value for each body part was studied by plotting the histogram of the frequency versus deviation and comparing this with the dose delivered to the midline of the umbilicus to where the dose was prescribed. The correlation of dose deviation to body part thickness was also studied. By studying the dose deviations, we can find the uniformity of general dose distributions for conventional TBI treatments. Results: The retrospective dosimetry study of the 129 TBI patient treatments indicates that for most of the patients treated in our clinic, the doses received by different body parts monitored with in vivo dosimetry were within the window of 10% difference from the prescribed dose. The inhomogeneity of dose on different body parts could be manually improved by using compensators, but the method is cumbersome and time consuming. The dose deviation in many histograms ranging from about ?10% to 10% indicates some incongruity of dose distribution. This could be due to the method of using lead compensato
基金part of thoughts of the HRP2(Hospitals:Grouping,Sharing and Piloting)project which involves French laboratories hospitals which was sponsored by the Region Rhne-Alpes.It has been realized in the framework of a research project fulfilled in the Belgian laboratory MAAD(Applied Mathematics Decision-making Aid)with the cooperation of a Belgian Hospital"Tivoli".The original version was presented on ICSSSM’06.
文摘Operating Theatre is the centre of the hospital management＇s efforts. It constitutes the most expensive sector with more than 10% of the intended operating budget of the hospital. To reduce the costs while maintaining a good quality of care, one of the solutions is to improve the existent planning and scheduling methods by improving the services and surgical specialty coordination or finding the best estimation of surgical case durations. The other solution is to construct an effective surgical case plan and schedule. The operating theatre planning and scheduling is the two important steps, which aim to make a surgical case programming with an objective of obtaining a realizable and efficient surgical case schedule. This paper focuses on the first step, the operating theatre planning problem. Two planning methods are introduced and compared. Real data of a Belgian university hospital ＂Tivoli＂ are used for the experiments.
文摘The paper discusses an extended entropy model for the prediction of trip amount and provides a method to solve it, called the simple block iterative algorithm, from the point of view of the system of nonlinear equations. Because the algorithm gives consideration to the characteristic of the model, it has better effect in our practice. The paper also studies the existence and uniqueness of the solution and convergence of the algorithm.
