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1.
Radiol Manage ; 38(2): 14-9; quiz 20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27172647

RESUMEN

Internally promoting clinical staff members into management positions is often a wise organizational strategy. Although there are advantages in doing such, there are also a number of challenges. Newly appointed managers may need introductory management level training given technical expertise does not always equate to management expertise. Devoting time to teaching even the most basic management skills will assure a more seamless role transition for the promoted employee. Upper administration also needs to be aware that possessing clinical expertise does not always serve as a precursor to promotion. Not every clinical employee, regardless of how proficient they are in their technical roles, seeks to be a manager.


Asunto(s)
Movilidad Laboral , Cuerpo Médico de Hospitales , Servicio de Radiología en Hospital/organización & administración , Educación Continua , Humanos , Selección de Personal/métodos
2.
Med Dosim ; 39(3): 272-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24913467

RESUMEN

To describe a dosimetric method using an anterior dose avoidance structure (ADAS) during the treatment planning process for intensity-modulated radiation therapy (IMRT) for patients with anal canal and rectal carcinomas. A total of 20 patients were planned on the Elekta/CMS XiO treatment planning system, version 4.5.1 (Maryland Heights MO) with a superposition algorithm. For each patient, 2 plans were created: one employing an ADAS (ADAS plan) and the other replanned without an ADAS (non-ADAS plan). The ADAS was defined to occupy the volume between the inguinal nodes and primary target providing a single organ at risk that is completely outside of the target volume. Each plan used the same beam parameters and was analyzed by comparing target coverage, overall plan dose conformity using a conformity number (CN) equation, bowel dose-volume histograms, and the number of segments, daily treatment duration, and global maximum dose. The ADAS and non-ADAS plans were equivalent in target coverage, mean global maximum dose, and sparing of small bowel in low-dose regions (5, 10, 15, and 20 Gy). The mean difference between the CN value for the non-ADAS plans and ADAS plans was 0.04 ± 0.03 (p < 0.001). The mean difference in the number of segments was 15.7 ± 12.7 (p < 0.001) in favor of ADAS plans. The ADAS plan delivery time was shorter by 2.0 ± 1.5 minutes (p < 0.001) than the non-ADAS one. The ADAS has proven to be a powerful tool when planning rectal and anal canal IMRT cases with critical structures partially contained inside the target volume.


Asunto(s)
Neoplasias del Ano/radioterapia , Carcinoma/radioterapia , Planificación de la Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Humanos , Radiometría
3.
Med Phys ; 34(10): 3760-7, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17985621

RESUMEN

The technology of online mega-voltage cone-beam (CB) computed tomography (MV-CBCT) imaging is currently used in many institutions to generate a 3D anatomical dataset of a patient in treatment position. It utilizes an accelerator therapy beam, delivered with 200 degrees gantry rotation, and captured by an electronic portal imager to account for organ motion and setup variations. Although the patient dose exposure from a single volumetric MV-CBCT imaging procedure is comparable to that from standard double-exposure orthogonal portal images, daily image localization procedures can result in a significant dose increase to healthy tissue. A technique to incorporate the daily dose, from a MV-CBCT imaging procedure, in the IMRT treatment planning optimization process was developed. A composite IMRT plan incorporating the total dose from the CB was optimized with the objective of ensuring uniform target coverage while sparing the surrounding normal tissue. One head and neck cancer patient and four prostate cancer patients were planned and treated using this technique. Dosimetric results from the prostate IMRT plans optimized with or without CB showed similar target coverage and comparable sparing of bladder and rectum volumes. Average mean doses were higher by 1.6 +/- 1.0 Gy for the bladder and comparable for the rectum (-0.3 +/- 1.4 Gy). In addition, an average mean dose increase of 1.9 +/- 0.8 Gy in the femoral heads and 1.7 +/- 0.6 Gy in irradiated tissue was observed. However, the V65 and V70 values for bladder and rectum were lower by 2.3 +/- 1.5% and 2.4 +/- 2.1% indicating better volume sparing at high doses with the optimized plans incorporating CB. For the head and neck case, identical target coverage was achieved, while a comparable sparing of the brain stem, optic chiasm, and optic nerves was observed. The technique of optimized planning incorporating doses from daily online MV-CBCT procedures provides an alternative method for imaging IMRT patients. It allows for daily treatment modifications where other volumetric tomographic imaging techniques may not be feasible and/or available and where accurate patient localization with a high degree of precision is required.


Asunto(s)
Adenoma/radioterapia , Tomografía Computarizada de Haz Cónico/métodos , Neoplasias Hipofisarias/radioterapia , Neoplasias de la Próstata/radioterapia , Radiometría/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia de Intensidad Modulada/métodos , Humanos , Masculino , Aceleradores de Partículas , Fotones , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Dosificación Radioterapéutica , Reproducibilidad de los Resultados
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