46 research outputs found
Forearm Rotation Range of Motion and Its Velocity in Eating With Chopsticks : a Comparison Among Positions of Dish
The purpose of this study was to determine range of motion of forearm rotation and its velocity in eating. Six young students (age:20.5±0.5 years [range:20-21], 2 men and 4 women) participated in this study. To measure three-dimensional motions, we used an electromagnetic tracking device system. The first sensor was attached to the dorsal/distal of forearm with sprint, and the second sensor was attached to the dorsal/medial ulna with elastic belt. The subjects ate pickles with chopsticks. At a wooden desk with 70cm height they sat on a height-adjustable chair, so their olecranon was as high as the desk top. Three positions of a dish were measured; A: at the distance of length of distal to elbow, B: at the distance of length of the upper extremity, and C: at a middle position between A and B. The results revealed that forearm rotation, range of motion and its velocity were significantly different among three conditions (one-way repeated-measure ANOVA)(p<0.05). Characteristically the motion velocity of B was lower than C, and A was lower than C (p<0.05). Findings suggest that 1) limited forearm range of motion would decrease a burden of forearm by setting a dish at B or C than A, 2) the rotation (maximal pronation and supination: 11 and 49 degrees, respectively) was similar, to a fork (maximal pronation and supination: 10 and 51 degrees, respectively), 3) C may be efficiently operated, and 4) the system may be instructed as a good equipment for eating
Dosimetric consequences of the shift towards computed tomography guided target definition and planning for breast conserving radiotherapy
Background: The shift from conventional two-dimensional (2D) to three-dimensional (3D)conformal target definition and dose-planning seems to have introduced volumetric as well as geometric changes. The purpose of this study was to compare coverage of computed tomography (CT)-based breast and boost planning target volumes (PTV), absolute volumes irradiated, and dose delivered to the organs at risk with conventional 2D and 3D-conformal breast conserving radiotherapy. Methods: Twenty-five patients with left-sided breast cancer were subject of CT-guided target definition and 3D-conformal dose-planning, and conventionally defined target volumes and treatment plans were reconstructed on the planning CT. Accumulated dose-distributions were calculated for the conventional and 3D-conformal dose-plans, taking into account a prescribed dose of 50 Gy for the breast plans and 16 Gy for the boost plans. Results: With conventional treatment plans, CT-based breast and boost PTVs received the intended dose in 78% and 32% of the patients, respectively, and smaller volumes received the prescribed breast and boost doses compared with 3D-conformal dose-planning. The mean lung dose, the volume of the lungs receiving > 20 Gy, the mean heart dose, and volume of the heart receiving > 30 Gy were significantly less with conventional treatment plans. Specific areas within the breast and boost PTVs systematically received a lower than intended dose with conventional treatment plans. Conclusion: The shift towards CT-guided target definition and planning as the golden standard for breast conserving radiotherapy has resulted in improved target coverage at the cost of larger irradiated volumes and an increased dose delivered to organs at risk. Tissue is now included into the breast and boost target volumes that was never explicitly defined or included with conventional treatment. Therefore, a coherent definition of the breast and boost target volumes is needed, based on clinical data confirming tumour control probability and normal tissue complication probability with the use of 3D-conformal radiotherapy
Guideline adherence for early breast cancer before and after introduction of the sentinel node biopsy
This population-based study aimed to analyse variations in surgical treatment and guideline compliance with respect to the application of radiotherapy and axillary lymph node dissection (ALND), for early breast cancer, before and after the sentinel node biopsy (SNB) introduction. The study included 13 532 consecutive surgically treated stage I–IIIA breast cancer patients diagnosed in 1989–2002. Hospitals showed large variation in breast-conserving surgery (BCS) rates, ranging between 27 and 72% for T1 and 14 and 42% for T2 tumours. In multivariate analysis marked inter-hospital and time-dependent variation in the BCS rate remained after correction for case-mix. The guideline adherence was markedly lower for elderly patients. In 25.2% of the patients aged ⩾75 years either ALND or radiotherapy were omitted. The proportion of patients with no ALND after an SNB increased from 1.8% in 1999 to 37.8% in 2002. However, in 2002 also 12.2% of the patients with a positive SNB did not have an ALND. Guideline compliance for BCS, with respect to radiotherapy and ALND, fell since the SNB introduction, from 96.1% before 2000 to 91.4% in 2002 (P<0.001). Noncompliance may however reflect patient-tailored medicine, as for elderly patients with small, radically resected primary tumours. The considerable variation in BCS-rates is more consistent with variations in surgeon preferences than patient's choice
Radiotherapeutische mogelijkheden voor het kind met een hersentumor
Brain tumours in children require a multidisciplinary approach. The relapse rate after surgery alone is high in certain types of tumours, so adjuvant treatment is necessary. Radiotherapy is the treatment after surgery in most of the brain tumours. The goal of radiotherapy is to give the optimal dose to the target volume and to spare the normal tissues. These aspects can be reached with the newer three dimensional techniques. In this article the treatment of a few tumours will be described as well as the late effects of radiation therapy.Brain tumours in children require a multidisciplinary approach. The relapse rate after surgery alone is high in certain types of tumours, so adjuvant treatment is necessary. Radiotherapy is the treatment after surgery in most of the brain tumours. The goal of radiotherapy is to give the optimal dose to the target volume and to spare the normal tissues. These aspects can be reached with the newer three dimensional techniques. In this article the treatment of a few tumours will be described as well as the late effects of radiation therapy.</p
Minimising contralateral breast dose in post-mastectomy intensity-modulated radiotherapy by incorporating conformal electron irradiation
PURPOSE: To assess the potential benefit of incorporating conformal electron irradiation in intensity-modulated radiotherapy (IMRT) for loco-regional post-mastectomy RT. PATIENTS AND METHODS: Ten consecutive patients that underwent left-sided mastectomy were selected for this comparative planning study. Three-dimensional conformal radiotherapy (3D-CRT) photon-electron dose plans were compared to photon-only IMRT (IMRT(p)) and photon IMRT with conformal electron irradiation (IMRT(p/e)). The planning target volume (PTV) was prescribed 50 Gy and included the chest wall and the internal mammary and supra-clavicular lymph node regions. It was attempted to minimise dose delivered to heart, lungs and contralateral breast (CB), while maintaining adequate PTV coverage. RESULTS: All plans complied with objectives for PTV coverage. IMRT(p/e) eliminated volumes receiving 70 Gy (V70) that were present in 3D-CRT at the junction of photon and electron beams. Both IMRT strategies reduced heart V30 significantly below 3D-CRT levels. Mean heart dose with IMRT(p/e) was the lowest and was equal to that with 3D-CRT. Minimising heart dose with IMRT(p) resulted in irradiated CB volumes much larger than that with 3D-CRT. With IMRT(p/e), CB dose was only slightly increased when compared to 3D-CRT. Mean lung dose values were similar for IMRT and 3D-CRT. With IMRT, lung V20 was smaller, whereas V5 values for heart, lung and CB were higher than those with 3D-CRT. CONCLUSIONS: Incorporation of conformal electron irradiation in post-mastectomy IMRT(p/e) enables a heart dose reduction which can only be obtained with IMRT(p) when allowing large irradiated volumes in the contralateral breast