765 research outputs found

    Intraoperative computed tomography imaging for dose calculation in intraoperative electron radiation therapy: Initial clinical observations

    Get PDF
    In intraoperative electron radiation therapy (IOERT) the energy of the electron beam is selected under the conventional assumption of water-equivalent tissues at the applicator end. However, the treatment field can deviate from the theoretic flat irradiation surface, thus altering dose profiles. This patient-based study explored the feasibility of acquiring intraoperative computed tomography (CT) studies for calculating three-dimensional dose distributions with two factors not included in the conventional assumption, namely the air gap from the applicator end to the irradiation surface and tissue heterogeneity. In addition, dose distributions under the conventional assumption and from preoperative CT studies (both also updated with intraoperative data) were calculated to explore whether there are other alternatives to intraoperative CT studies that can provide similar dose distributions. The IOERT protocol was modified to incorporate the acquisition of intraoperative CT studies before radiation delivery in six patients.This study was supported by Ministerio de Ciencia, Innovación y Universidades (http://www.ciencia.gob.es) [grant number TEC2013–48251-C2 to JP, VG-V and MJL-C], co-funded by European Regional Development Fund (ERDF), “A way of making Europe” (https://ec.europa.eu/regional_policy/en/funding/erdf); by Ministerio de Ciencia, Innovación y Universidades (http://www.ciencia.gob.es), Instituto de Salud Carlos III (https://www.isciii.es) [grant numbers DTS14/00192 to JP, VG-V and FAC; PI15/02121 to FAC and JC-H; PI18/01625 to JP], co-funded by European Regional Development Fund (ERDF), “A way of making Europe” (https://ec.europa.eu/regional_policy/en/funding/erdf); and by Comunidad de Madrid (http://www.comunidad.madrid) [grant number TOPUS-CM S2013/MIT3024 to JP], co-funded by European Structural and Investment Fund (https://ec.europa.eu/info/funding-tenders/funding-opportunities/funding-programmes/overview-funding-programmes_en). The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades (http://www.ciencia.gob.es) and the Pro CNIC Foundation (https://www.fundacionprocnic.es) [to MD], and is a Severo Ochoa Center of Excellence (SEV-2015-0505). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Stereotactic radiosurgery for the treatment of recurrent high-grade gliomas: long-term follow-up

    Get PDF
    High-grade gliomas (HGG) are the most frequent primary central nervous system tumors; treatment of HCGs includes surgery and post-operative conformal radiotherapy associated with temozolomide (TMZ or procarbazine/lomustine/vincristine [PCV], specifically in patients with anaplastic oligodendrogliomas or anaplastic oligoastrocytomas). However, recurrence is common. Re-irradiation has been utilized in this setting for years and remains a feasible option, although there is always a concern regarding toxicity. Modern high-precision conformal techniques, including stereotactic radiosurgery (SRS), could improve the therapeutic ratio by delivering high biologically equivalent doses while reducing high-dose radiotherapy (RT) to normal brain tissue. In this paper, we present the results obtained after prolonged follow-up in patients who underwent SRS as a treatment for recurrent high-grade gliomas at San Francisco Hospital in Madrid, Spain

    Effects of the Menstrual Cycle on Jumping, Sprinting and Force-Velocity Profiling in Resistance-Trained Women: A Preliminary Study

    Get PDF
    The aim of this study was to examine the effects of the menstrual cycle on vertical jumping, sprint performance and force-velocity profiling in resistance-trained women. A group of resistancetrained eumenorrheic women (n = 9) were tested in three phases over the menstrual cycle: bleeding phase, follicular phase, and luteal phase (i.e., days 1–3, 7–10, and 19–21 of the cycle, respectively). Each testing phase consisted of a battery of jumping tests (i.e., squat jump [SJ], countermovement jump [CMJ], drop jump from a 30 cm box [DJ30], and the reactive strength index) and 30 m sprint running test. Two different applications for smartphone (My Jump 2 and My Sprint) were used to record the jumping and sprinting trials, respectively, at high speed (240 fps). The repeated measures ANOVA reported no significant differences (p ≥ 0.05, ES < 0.25) in CMJ, DJ30, reactive strength index and sprint times between the different phases of the menstrual cycle. A greater SJ height performance was observed during the follicular phase compared to the bleeding phase (p = 0.033, ES = −0.22). No differences (p ≥ 0.05, ES < 0.45) were found in the CMJ and sprint force-velocity profile over the different phases of the menstrual cycle. Vertical jump, sprint performance and the force-velocity profiling remain constant in trained women, regardless of the phase of the menstrual cycle.Pre-competitive Projects for Early Stage Researchers Programme from the University of Granada (ref: PPJIA2020.03

    Estudio de la viabilidad de la integración de un Sistema de Posicionamiento Óptico en el entorno de la radioterapia intraoperatoria

    Get PDF
    Actas de: XXIX Congreso Anual de la Sociedad Espñaola de Ingeniería Biomédica (CASEIB 2011). Cáceres, 16-18 Noviembre 2011.La radioterapia intraoperatoria (RIO) es una técnica que combina cirugía y radioterapia, que se aplica en pacientes con tumores para los que se ha indicado su resección y con alto riesgo recidivante. El oncólogo radioterapeuta planifica esta intervención sobre una imagen TAC del paciente. Sin embargo, los datos del escenario real encontrado en la sala de tratamiento (posición y orientación del aplicador respecto del paciente y energía del haz) se deben recoger de forma manual para actualizar la planificación. Esta información es muy valiosa para la documentación y posterior seguimiento del procedimiento realizado. En este trabajo se evalúa la viabilidad de la integración de un sistema de posicionamiento óptico en el entorno RIO, y su precisión para localizar el aplicador sobre la imagen de planificación.Este trabajo ha sido financiado por el Minsiterio de Ciencia e Innovación (PI09/90568 IPT-3000000-2010-3, TEC2010-21619-C04-01), la Comunidad de Madrid (ARTEMIS S2009/DPI-1802) y fondos FEDER.Publicad

    ESTRO IORT Task Force/ACROP recommendations for intraoperative radiation therapy in borderline-resected pancreatic cancer

    Get PDF
    Radiation therapy (RT) is a valuable component of multimodal treatment for localized pancreatic cancer. Intraoperative radiation therapy (IORT) is a very precise RT modality to intensify the irradiation effect for cancer involving upper abdominal structures and organs, generally delivered with electrons (IOERT). Unresectable, borderline and resectable disease categories benefit from dose-escalated chemoradiation strategies in the context of active systemic therapy and potential radical surgery. Prolonged preoperative treatment may act as a filter for selecting patients with occult resistant metastatic disease. Encouraging survival rates have been documented in patients treated with preoperative chemoradiation followed by radical surgery and IOERT (>20 months median survival, >35% survival at 3 years). Intensive preoperative treatment, including induction chemotherapy followed by chemoradiation and an IOERT boost, appears to prolong long-term survival within the subset of patients who remain relapse-free for>2 years (>30 months median survival; >40% survival at 3 years). Improvement of local control through higher RT doses has an impact on the survival of patients with a lower tendency towards disease spread. IOERT is a well-accepted approach in the clinical scenario (maturity and reproducibility of results), and extremely accurate in terms of dose-deposition characteristics and normal tissue sparing. The technique can be adapted to systemic therapy and surgical progress. International guidelines (National Comprehensive Cancer Network or NCCN guidelines) currently recommend use of IOERT in cases of close surgical margins and residual disease. We hereby report the ESTRO/ACROP recommendations for performing IOERT in borderline-resectable pancreatic cancer

    Intraoperative radiotherapy in the multidisciplinary treatment of bone sarcomas in children and adolescents

    Get PDF
    From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisciplinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6-20 MeV electron beams. The median follow-up time for the entire group is 25 months (2-65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT

    Radioterapia śródoperacyjna u chorych na nowotwory złośliwe przewodu pokarmowego: współczesne wyniki leczenia skojarzonego

    Get PDF
    Abstract The integration of intraoperative radiotherapy (IORT) into the multimodal treatment of gastrointestinal cancer is feasible and leads to high rates of local control. In-field tumoral control using IORT-containing strategies can be achieved in over 90% of most cases, regardless of the site or status of the tumor (primary or recurrent). Electron beam IORT, or intraoperative electron radiation therapy, is the dominant technology used in institutions reporting data in publications the 21st century. Neither surgery nor systemic therapy is compromised by the integration of IORT-containing radiotherapy.Wprowadzenie radioterapii śródoperacyjnej (IORT, integration of intraoperative radiotherapy) do schematów leczenia skojarzonego u chorych na nowotwory przewodu pokarmowego jest możliwe i może prowadzić do poprawy wyleczalności miejscowej. Wyleczenie w objętości napromienianej można osiągnąć w około 90% przypadków leczonych schematami z udziałem IORT, niezależnie od lokalizacji i statusu guza (pierwotny lub nawrotowy). Terapia IORT wiązką elektronową (śródoperacyjna radioterapia elektronowa) jest dominującą techniką stosowaną w ośrodkach publikujących najnowsze doniesienia. Leczenie z wykorzystaniem IORT nie zastępuje jednak ani chirurgii, ani postępowania systemowego

    An innovative tool for intraoperative electron beam radiotherapy simulation and planning: description and initial evaluation by radiation oncologists

    Get PDF
    The lack of specific treatment planning tools limits the spread of Intraoperative Electron Radiation Therapy. An innovative simulation and planning tool is presented. Applicator positioning, isodose curves, and doseevolume histograms can be estimated for previously segmented regions to treat/protect. Evaluation by three radiation oncologists on 15 patients showed high parameter agreement in nine cases, demonstrating the possibilities in cases involving different anatomical locations, and identifying the importance of specialized surgical input in the preplanning process.Supported by grants PI08/90473, IPT 300000 2010 3, ARTEMIS S2009/DPI 1802(CAM), TEC2010 21619 C04 01, PI09/90568, ERD Funds.Publicad

    Cirugía derivativa más radioterapia intraoperatoria y externa en el carcinoma de páncreas localizado e irresecable

    Get PDF
    Presentamos una serie de 25 casos de carcinomas de páncreas localmente avanzados e irresecables, sin metástasis a distancia, tratados con cirugía derivativa, radioterapia intraoperatoria e irradiación externa: 18 tumores de cabeza (16 con ictericia obstructiva) y 7 de cuerpo. Se realizó derivación biliar en 18 y gastroyeyunostomía en 19. La mortalidad operatoria fue nula, con una morbilidad del 16%. A largo plazo se produjeron 3 hemorragias digestivas, 2 ictericias obstructivas, una colangitis y una obstrucción intestinal. Se obtuvo un 72% de control local de la enfermedad y todos los fallecidos por progresión tumoral desarrollaron metástasis hepáticas y/o peritoneales. Presentaban dolor pancreático 22 pacientes y 20 experimentaron remisión del mismo en una a 2 semanas. La analgesia fue definitiva en 12 y reapareció el dolor tardíamente en ocho. La supervivencia media fue de 9 meses (rango 4-24). La revisión de la literatura pone de manifiesto la indicación de la radioterapia externa tanto en el carcinoma de páncreas irresecable y no metastásico como en los resecados. La asociación de radioterapia intraoperatoria tiene, así mismo, un papel importante en cuanto a supervivencia, paliación del dolor y de la progresión local. El 5-fluorouracilo asociado al tratamiento radioterápico prolonga significativamente la supervivencia con una morbilidad razonable

    Prone to supine surface-based registration for surgical planning in breast cancer treatment

    Get PDF
    Breast cancer is the most common invasive cancer in women worldwide. Many women with breast cancer have their malignant tumors detected before the lesions become clinically palpable. Occult lesions must be marked for the surgeon to ensure that they can be effectively resected. Image-guided wire localization (WGL) is the current standard of care for the excision of non-palpable carcinomas during breast conserving surgery. The integration of the information from multimodal imaging may be especially relevant in surgical planning as complement or an alternative to WGL. The combination of information from images in different positions is especially difficult due to large breast deformation. This work presents a system based on surface registration to localize the lesion in the operative position, starting from a prone MRI study and a surface of the patient in the supine positon. The pre-operative surface from the MRI is registered to the surface obtained in a supine position similar to the intraoperative setting. Triangular meshes have been used to model breast surface in both positions and surfaces are aligned using a Laplacian deformation with fiducials automatically obtained from 3 anatomical references. The evaluation of the methodology has been carried out in 13 cases in which a supine- CT was available achieving an average localization error of 6.7 m
    corecore