Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Planning”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 91 records · Page 5Linked to original sources
PubMed1994

Consideration of time-dose-patterns in 3D treatment planning. An approach towards 4D treatment planning.

PURPOSE: The rendering of the 3D dose distribution together with anatomical information and the volumes of interest (VoI) is essential to get a visual impression of the treatment plan and to find modifications for the optimization of the dose distribution. The integration of biological effects into the 3D treatment planning is of interest for the assessment of different time-dose patterns. MATERIALS AND METHODS: One way of taking into account biological data is to relate the physical dose in critical structures to the corresponding tolerance dose. For that purpose the applied time-dose pattern has to be converted into the standard fractionation scheme being the basis of the tolerance dose. Generally any model can be used for these calculations. Here a modified incomplete repair model is used to calculate the relative biological dose distribution (RBD). The visualization of these biologically isoeffective dose distributions can be performed in the same manner as the physical dose so that the physical and biological dose distributions can by displayed side by side. As this is equivalent to introducing the time as a fourth dimension into 3D treatment planning this is called 4D treatment planning. RESULTS: From 3D dose matrices the biologically isoeffective dose distributions are calculated for the organs at risk. The changes introduced by different time-dose patterns are displayed using the same technique as for rendering 3D treatment plans. The visualisation of the three-dimensional biological dose distributions is shown by means of a patient with an oesophagus carcinoma. The RBD related to the tolerance dose of the organs at risk is displayed for different time-dose fractionations. CONCLUSION: The RBD distribution on a 3D treatment plan can be displayed in the same mode as the physical dose distribution. This offers additionally valuable information in a 3D treatment planning process about the dose to critical organs and the influence of different time-dose patterns.

Color↗
PubMed2003

A method of predicting workload and staffing level for radiotherapy treatment planning as plan complexity changes.

When assessing the impact on workload from an expanding number of new patients and increasing treatment complexity, radiotherapy clinics find that oversimplified workload parameters, such as number of patients or number of fields, are not suitable for managing and predicting workload and organisational dimension. Although the basic treatment equivalent concept is available for predicting linear accelerator utilisation, no corresponding parameter has been available for radiotherapy treatment planning. In this study, we derive a simple workload indicator for treatment planning. The dose plan unit (DPU) takes the complexity of the treatment plan into account. Categorising plans according to complexity in their production, and measuring corresponding time for completing the plans in these categories, leads to the following baseline values for workload prediction: 1 DPU (non-computed tomography [CT]), 3 DPU (CT-contour) and 6 DPU (full-CT). The measured average productivity of 0.65 DPU per hour (1 standard deviation, SD = 0.08 DPU), or alternatively 1 DPU = 92 min, for a dosimetrist in this clinic indicates that 79.0 DPU can be produced by each dosimetrist per month within normal working hours. The predictive power of the DPU is shown in terms of using it to quantify the impact on workload in treatment planning of changing treatment protocols for a particular anatomic treatment site.

Analysis of Variance↗
PubMed2004

Inversely planned intensity modulated radiotherapy of the breast including the internal mammary chain: a plan comparison study.

The aim of this paper is to evaluate the benefit of inversely planned intensity modulated radiotherapy (IMRT) in the adjuvant irradiation of breast cancer when internal mammary lymph nodes are included in the treatment volume. 20 patients treated with 3D-planned conventional radiotherapy (CRT) following breast conserving surgery were included in the study. We chose 10 patients with left-sided and 10 patients with right-sided tumors. All treatment volumes included the internal mammary chain. For plan comparison to the applied CRT plan an inverse IMRT-plan in, step-and-shoot'-technique was calculated. For all patients IMRT resulted in an improved conformity of dose distribution to the target volume compared to CRT (mean COIN95: 0.798 vs. 0.514 with COIN95 = C1 * C2 (C1= fraction of CTV that is covered by > 95% of the prescribed dose and C2 = volume of CTV that is covered by > 95% of the prescribed dose/total volume that is covered by > 95% of the prescribed dose). In all cases with matching adjacent beams, the homogeneity in the target volume was improved. The volume of the ipsilateral lung irradiated with a dose higher than 20 Gy was reduced with IMRT from 24.6% to 13.1% compared to CRT. For left-sided target volume the heart volume with a dose higher than 30 Gy was reduced from 6.2% to 0.2%. The presented plan comparison study for irradiation of the breast and the parasternal lymph nodes showed a substantial improvement of the dose distribution by inversely planned IMRT compared to CRT. This is visible for the target volume, the ipsilateral lung and, in case of left-sided target volume, the heart. Despite an increase in integral dose to the entire normal tissue, the application of IMRT might be clinically advantageous in cases where no satisfying dose distribution can be obtained by CRT.

Breast Neoplasms↗
PubMed2003

A simple meal plan emphasizing healthy food choices is as effective as an exchange-based meal plan for urban African Americans with type 2 diabetes.

OBJECTIVE: To compare a simple meal plan emphasizing healthy food choices with a traditional exchange-based meal plan in reducing HbA(1c) levels in urban African Americans with type 2 diabetes. RESEARCH DESIGN AND METHODS: A total of 648 patients with type 2 diabetes were randomized to receive instruction in either a healthy food choices meal plan (HFC) or an exchange-based meal plan (EXCH) to compare the impact on glycemic control, weight loss, serum lipids, and blood pressure at 6 months of follow-up. Dietary practices were assessed with food frequency questionnaires. RESULTS: At presentation, the HFC and EXCH groups were comparable in age (52 years), sex (65% women), weight (94 kg), BMI (33.5), duration of diabetes (4.8 years), fasting plasma glucose (10.5 mmol/l), and HbA(1c) (9.4%). Improvements in glycemic control over 6 months were significant (P < 0.0001) but similar in both groups: HbA(1c) decreased from 9.7 to 7.8% with the HFC and from 9.6 to 7.7% with the EXCH. Improvements in HDL cholesterol and triglycerides were comparable in both groups, whereas other lipids and blood pressure were not altered. The HFC and EXCH groups exhibited similar improvement in dietary practices with respect to intake of fats and sugar sweetened foods. Among obese patients, average weight change, the percentage of patients losing weight, and the distribution of weight lost were comparable with the two approaches. CONCLUSIONS: Medical nutrition therapy is effective in urban African Americans with type 2 diabetes. Either a meal plan emphasizing guidelines for healthy food choices or a low literacy exchange method is equally effective as a meal planning approach. Because the HFC meal plan may be easier to teach and easier for patients to understand, it may be preferable for low-literacy patient populations.

Black or African American↗
PubMed2003

Integrated urban water planning: big picture planning is good for the wallet and the environment.

The demands on governments and local authorities are changing in response to community expectations for environmentally sustainable outcomes. To reverse declining water quality in rivers and ensure sustainable use in the 21st century, the State Government in New South Wales has introduced a package of Water Reforms. The introduction of integrated water, sewerage and drainage planning is one of the Water Reform initiatives. Traditionally, government and local authorities have managed their water supply, sewerage and stormwater drainage systems as separate entities. Integrated urban water planning is a structured planning process to evaluate concurrently the opportunities to improve the management of water, sewerage and drainage services within an urban area in ways which are consistent with broader catchment and river management objectives. The New South Wales Department of Land & Water Conservation (DLWC) has developed an integrated urban water planning process through a number of recent pilot studies. The process links urban water management objectives to overall catchment and river management objectives. DLWC is currently developing a set of guidelines for integrated urban water plans. DLWC has developed the Integrated Urban Water Planning methodology through three pilot studies in the New South Wales towns of Finley, Goulburn and Bombala. The pilot studies have shown that an integrated approach to water, sewerage and stormwater planning can identify opportunities that are not apparent when separate strategies are developed for each service. The result is better-integrated, more sustainable solutions, and substantial cost savings for local communities.

Cities↗
PubMed1992

Planning for strategic change? A participative planning approach for community hospitals.

Strategic planning is becoming to hospitals what business case analysis is to private corporations. In fact, this type of planning is becoming essential for the professional management of Ontario hospitals. The participative strategic planning process at Toronto East General Hospital (TEGH) is an example of how a professionally structured and implemented strategic planning process can be successfully developed and implemented in a community hospital. In this article, the environmental factors driving planning are reviewed and the critical success factors for the development and implementation of a strategic plan are examined in the context of TEGH's experience.

Decision Making, Organizational↗
PubMed2006

[Dosimetric consequences of the application of a rectum hull-planning volume for treatment planning of intensity modulated radiotherapy of prostate cancer].

The present study evaluated a hull-volume definition strategy for the planning organ at risk volume (PRV) for the rectum in the planning of radiotherapy of prostate cancer. The bounding volumes of rectum contours of 1 to 5 CT scans were compared on the basis of the rectum coverage probabilities for 5 patients. In addition, IMRT treatment plans were optimized using the rectum hull PRV5 of 5 CTs and each of the conventional rectum contours PRV1. The plans were compared on the basis of the organ doses caused by the individual organ motion. PRV5 allowed to cover the rectum with a probability of nearly 90% (PRV1 67%). Rectal wall dose showed a great variability for PRV1, while planned and treatment dose agreed well for PRV5 due to the improved geometric information which resulted in a better rectal sparing. In conclusion, the rectum hull-volume PRV5 is a well suited PRV for planning of IMRT dose distributions allowing dose escalation as well as rectal sparing.

Humans↗
PubMed1985

Facility planning as a component of strategic planning.

Facility planning is an important component of health care strategic planning, for it provides an accurate assessment of the institution's physical environment and its development potential. This article, the second in HCSM's series on the organizational components of strategic planning, reviews the role of facilities planning, the functional and physical evaluation, space programming, and facilities master plan in the development and implementation of the strategic plan.

Facility Design and Construction↗
PubMedDate not supplied

Managed health care plans in Southern United States municipalities: empirical evidence on choice of plan.

This study examines factors that influence choice of Southern municipal government health care plans in the United States. Using survey data, this article specifically examines the managed care offerings of Health Maintenance Organizations (HMO), Preferred Provider Organizations (PPO) and Point of Service (POS) plans. Some of the more interesting empirical results indicate that HMO plans are associated more with employee satisfaction; PPO plans are associated with cost containment; and POS plans are more likely to provide health care benefits to part-time employees. Empirical evidence also indicates that employee satisfaction is increased when there is a greater choice of managed care plans available to municipal governments.

Administrative Personnel↗
PubMed2002

Inverse treatment planning and stereotactic intensity-modulated radiation therapy (IMRT) of the tumor and lymph node levels for nasopharyngeal carcinomas. Description of treatment technique, plan comparison, and case study.

PURPOSE: Inverse treatment planning and intensity-modulated radiation therapy (IMRT) promise advantages in the treatment of tumors of the head and neck region. Currently published studies use IMRT only in the treatment of the primary tumor. In these studies, the lymph nodes of the neck were treated using conventional techniques. The feasibility of an IMRT technique which allows treatment of the complete target volume, including the primary tumor and lymph nodes, without a beam split is described. PATIENT AND METHOD: For inverse treatment planning, the KonRad planning system was used. The primary as well as the secondary PTV (bilateral lymph node levels) were treated with one intensity-modulated primary plan. To increase the dose in the primary PTV and suspicious lymph nodes, an intensity-modulated boost plan was performed. The "step and shoot" IMRT technique was used. A plan comparison between the described IMRT approach and an IMRT approach using a split-beam technique was performed focusing on the treatment time. A patient with a carcinoma of the nasopharynx was treated with curative intent by a combined radiochemotherapy. RESULTS: The median total dose to the primary PTV was 70 Gy, to suspicious lymph nodes > or = 66.0 Gy, and to the secondary PTV 52 Gy. The defined maximum doses to the organs at risk were not exceeded, and the median dose to the protected parotid gland amounted to 21 Gy. Comparison of the treatment time between both IMRT approaches revealed only a slightly shorter treatment time (1-3 min) for the split-beam IMRT technique without considering the remaining conventional treatment parts of the split-beam IMRT technique. The patient achieved a complete response, and 18 months after treatment no signs of recurrent disease are visible. CONCLUSIONS: IMRT allows the treatment of the target volumes with high doses combined with an excellent sparing of the organs at risk. The IMRT approach presented here makes the treatment of the whole target volume with a single-beam arrangement feasible and does not increase the treatment time compared to a split-beam IMRT technique. Treatment time was comparable to a conventional three-field technique combined with electrons. This IMRT technique can prevent over- or underdosage at field matchlines in the head and neck region and, moreover, is able to spare parotid glands and therefore better avoid xerostomia compared to conventional techniques.

Algorithms↗
PubMed2003

Radiography-based treatment planning compared with computed tomography (CT)-based treatment planning for intracavitary brachytherapy in cancer of the cervix: analysis of dose-volume histograms.

PURPOSE: To analyze the dose-volume histograms (DVHs) of the tumor volume and organs at risk by CT-based treatment planning compared with conventional radiography-based treatment planning for intracavitary brachytherapy in cancer of the cervix. METHODS AND MATERIALS: Fifteen consecutive patients with cancer of the cervix (1 IB1, 3 IB2, 7 IIB, 4 IIIB) were treated with plastic CT-compatible HDR intracavitary applicators and underwent postimplant pelvic CT scans with applicators in place. CT-images were transferred to the PLATO treatment planning system. The gross tumor volume (GTV) and organs at risk were digitized. Dwell positions in the uterine tandem and colpostats were identified and registered for each patient. All patients were treated with 6 Gy per fraction to Point A using radiography-based planning. For the CT-based planning, DVHs were performed for the GTV, bladder, rectum, sigmoid colon, and small bowel in the pelvis. The dose delivered to 3% volume of the organs at risk (D3%) was compared with the respective ICRU reference doses. RESULTS: For stage IB(I), IB2, IIB, and IIIB disease the mean GTV was 20.5 cc, 56.6 cc (54.2-57.2), 63.7 cc (55.4-118.9), and 77.6 cc (49.4-102.9), respectively. The 6 Gy pear-shaped volume (PSV) encompassed an average GTV of 98.5%, 89.5%, 79.5%, and 59.5% for stages IBI, IB2, IIB, and IIIB, respectively. The mean dose for the ICRU bladder point and D3% was 3.72 Gy (1.51-5.53) and 4.74 Gy (1.70-10.10), respectively. The mean dose for the ICRU rectal point and D3% was 3.97 Gy (2.09-5.37) and 3.52 Gy (2.05-4.08), respectively. The D3% for the sigmoid colon was highest (3.88 Gy), followed by the rectum (3.52 Gy), and the small bowel (3.36 Gy). CONCLUSION: Radiography-based conventional treatment planning overestimates tumor dose, especially those with more advanced tumors. To correlate DVHs for tumor control, improved tumor imaging is necessary.

Brachytherapy↗
PubMed2006

Comparison of dose-volume histograms of IMRT treatment plans for ethmoid sinus cancer computed by advanced treatment planning systems including Monte Carlo.

BACKGROUND AND PURPOSE: To recompute clinical intensity-modulated treatment plans for ethmoid sinus cancer and to compare quantitatively the dose-volume histograms (DVHs) of the planning target volume (PTV) and the optic organs at risk. MATERIAL AND METHODS: Ten step-and-shoot intensity-modulated treatment plans were enrolled in this study. Large natural and surgical air cavities challenged the calculation systems. Each optimized treatment plan was recalculated by two superposition convolution (TMS and Pinnacle) and a Monte Carlo system (MCDE). To compare the resulting DVHs, a one-way ANOVA for repeated measurements was performed and multiple pairwise comparisons were made. RESULTS: The tails of the PTV-DVHs were significantly higher for the Monte Carlo system. The DVHs of the critical organs displayed some statistically but not always clinically significant differences. For the individual patients, the three planning systems sometimes reproduced clinically discrepant DVHs that were not significantly different when averaged over all patients. CONCLUSIONS: Dose to air cavities contains computational uncertainty. As this dose is clinically irrelevant and optimizing it is meaningless, we recommended extracting the air from the PTV when constructing the PTV-DVH. The planning systems considered reproduce DVHs that are significantly different, especially in the tail region of PTV-DVHs.

Dose-Response Relationship, Radiation↗
PubMed2004

Treatment planning for carbon ion radiotherapy in Germany: review of clinical trials and treatment planning studies.

The GSI carbon ion radiotherapy facility established the first completely active beam shaping system for heavy ions, using energy variation on the synchrotron and pencil beam scanning. The introduction of an active beam shaping system for carbon ions has considerable impact on the design of the treatment planning system (TPS). The TPS has to account for the capability of the beam delivery and the biological modelling, which is needed to calculate the RBE for the resulting varying depth dose modulation. The TPS used in clinical routine with carbon ions is described and its use in treatment planning studies are outlined. A clinical trial with carbon ion therapy as primary therapy for chordoma and chondrosarcoma of the base of skull has been completed in 2001. Currently, carbon ion therapy as a boost treatment together with conventional conformal photon therapy or IMRT is under investigation in clinical trials for adenoid cystic carcinoma, chordoma and chondrosarcoma of the cervical spine and sacrococcygeal chordoma. Treatment planning studies comparing carbon ion therapy with IMRT, using optimization of combination therapy, and optimization of beam-line design have already been completed. Analysis of uncertainties in treatment planning has been started with the investigation of range uncertainties stemming from CT imaging. Uncertainties coming from the beam delivery play only a minor role. An attempt to asses the uncertainties introduced in treatment plans by the biological modelling, was done, using phantom verification of calculated cell survival levels. The clinical trials and planning studies are of special importance for the upcoming new clinical ion facility of the Heidelberg university hospital.

Carbon↗
PubMed2002

Effects of CAHPS health plan performance information on plan choices by New Jersey Medicaid beneficiaries.

OBJECTIVE: To assess the effects of CAHPS health plan performance information on plan choices and decision processes by New Jersey Medicaid beneficiaries. DATA SOURCES/STUDY SETTING: The study sample was a statewide sample of all new Medicaid cases that chose Medicaid health plans during April 1998. The study used state data on health maintenance organization (HMO) enrollments and survey data for a subset of these cases. STUDY DESIGN: An experimental design was used, with new Medicaid cases randomly assigned to experimental or control groups. The experimental group received a CAHPS report along with the standard enrollment materials, and the control group did not. DATA COLLECTION: The HMO enrollment data were obtained from the state in June 1998, and evaluation survey data were collected from July to October 1998. PRINCIPAL FINDINGS: No effects of CAHPS information on HMO choices were found for the total sample. Further examination revealed that only about half the Medicaid cases said they received and read the plan report and there was an HMO with dominant Medicaid market share but low CAHPS performance scores. The subset of cases who read the report and did not choose this dominant HMO chose HMOs with higher CAHPS scores, on average, than did those in an equivalent control group. CONCLUSIONS: Health plan performance information can influence plan choices by Medicaid beneficiaries, but will do so only if they actually read it. These findings suggest a need for enhancing dissemination of the information as well as further education to encourage informed choices.

Adult↗
PubMed2005

Incorporating organ movements in IMRT treatment planning for prostate cancer: minimizing uncertainties in the inverse planning process.

We investigate an off-line strategy to incorporate inter fraction organ movements in IMRT treatment planning. Nowadays, imaging modalities located in the treatment room allow for several CT scans of a patient during the course of treatment. These multiple CT scans can be used to estimate a probability distribution of possible patient geometries. This probability distribution can subsequently be used to calculate the expectation value of the delivered dose distribution. In order to incorporate organ movements into the treatment planning process, it was suggested that inverse planning could be based on that probability distribution of patient geometries instead of a single snapshot. However, it was shown that a straightforward optimization of the expectation value of the dose may be insufficient since the expected dose distribution is related to several uncertainties: first, this probability distribution has to be estimated from only a few images. And second, the distribution is only sparsely sampled over the treatment course due to a finite number of fractions. In order to obtain a robust treatment plan these uncertainties should be considered and minimized in the inverse planning process. In the current paper, we calculate a 3D variance distribution in addition to the expectation value of the dose distribution which are simultaneously optimized. The variance is used as a surrogate to quantify the associated risks of a treatment plan. The feasibility of this approach is demonstrated for clinical data of prostate patients. Different scenarios of dose expectation values and corresponding variances are discussed.

Artifacts↗
PubMed2002

Dosimetric verification of inverse planned step and shoot multileaf collimator fields from a commercial treatment planning system.

An inverse treatment planning (ITP) module on a commercial treatment planning system (TPS) (Helax AB, Uppsala, Sweden) is being used for an in-house clinical trial for treatment of nasopharyngeal cancer with contralateral parotid sparing. Intensity modulated radiation therapy (IMRT) fields are delivered by step and shoot multileaf collimator (MLC) with a DMLC enabled Varian 2300 CD (Varian Associates, Palo Alto, CA). A series of testing procedures have been devised to quantify the modeling and delivery accuracy of routine clinical inverse planned IMRT using Helax TMS and the Varian step and shoot MLC delivery option. Testing was done on specific aspects of the TPS modeling germane to DMLC. Measured relative dose factors (head scatter plus phantom scatter) for small MLC fields, normalized to a 10x10 cm2 non-MLC field, were found to differ by 2-3% from the TPS values for the smallest of the fields tested. Relative distributions for small off axis fields were found to be in good agreement. A process for the routine clinical verification of IMRT fields has been implemented. Each IMRT field in an inverse plan is imported into a flat water tank plan and a "beam's eye view" (BEV) dose distribution is generated. This is compared to the corresponding measured BEV dose distribution. The IMRT verification process has also been performed using an anthropomorphic phantom. Large clinical fields (i.e., greater than 14.5 cm in the leaf direction) caused difficulties due to a vendor specific machine restriction, and several techniques for dealing with these were examined. These techniques were (i) the use of static stepping of closed junctions, (ii) the use of two separate IMRT fields for a given gantry angle, and (iii) restricting the overall maximum field size used. The overall process has allowed implementation of an in-house protocol for IMRT use on an initial clinical site. Results of the verification measurements for the first ten patients treated at this center reveal an average maximum dose per IMRT field delivered of 71.0 cGy, with a mean local deviation from the planned dose of -1.2 cGy, and a standard deviation of 2.4 cGy.

Algorithms↗
PubMed1997

Discharge planning: an examination of the perceptions and recommendations for improved discharge planning at the Montreal General Hospital.

Hospital discharge planning is an interdisciplinary hospital-wide process that assists patients and their families to develop a feasible post-hospital plan of care. In order to facilitate an effective, smooth and rapid discharge plan for patients, health care professionals involved in discharge planning must be aware of problems and current gaps in service delivery. In order to identify and address problems and service gaps in an acute care trauma centre, the Social Work Department of the Montreal General Hospital conducted a survey of 81 clinicians via a questionnaire and interviewed 15 managers and administrators as to their perceptions and recommendations of the discharge planning process in their hospital. Internal, external and psychosocial factors were examined and three categories of discharge impediments emerged: systems, resources and patient/family issues. Recommendations for improving the discharge planning process are discussed.

Attitude of Health Personnel↗
PubMed1984

Use of ambulatory care services in three provider plans: interactions between patient characteristics and plans.

A previous study of low-income enrollees in a closed-panel health maintenance organization (HMO) and a Blue Cross/Blue Shield (BC/BS) plan showed that the effect on the use of health services of the age, sex, health status, previous health care use, race, and family size of the enrollees was different in the two plans. We have replicated this study using the same two provider plans but studying a different group of white collar, middle class enrollees. A third plan, an experimental independent practice association (IPA), was also available for analysis. Utilization was defined as use (yes/no) and the quantity of use for those who used services (in standardized dollars). Significant interactions were detected between plan and all of the independent variables but race. The use of services in the HMO was least affected by enrollees' characteristics (age, sex, race, health status, prior use, family size) and use was most sensitive to patient characteristics in BC. In some respects, the IPA was more like the HMO and in other respects more like the BC/BS plan.

Adolescent↗