The Experts below are selected from a list of 123 Experts worldwide ranked by ideXlab platform
Richard Potte - One of the best experts on this subject based on the ideXlab platform.
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the influence of a rectal balloon tube as internal Immobilization Device on variations of volumes and dose volume histograms during treatment course of conformal radiotherapy for prostate cancer
International Journal of Radiation Oncology Biology Physics, 2002Co-Authors: Stefa Wachte, Natascha Gerstne, Daniela Dorne, Grego Goldne, Adriana Colotto, Andre Wambersie, Richard PotteAbstract:Purpose: A prospective comparative study of a subset of 10 consecutive patients was performed, to describe the effects of an air-inflated rectal balloon tube that has been used for prostate Immobilization in 360 patients since 1994. In particular, influences on prostate motion, rectum filling variations, and dose-volume histograms (DVHs) of the rectum during a course of conformal radiotherapy were investigated. Methods and Materials: Computed tomographic (CT) examinations without and with rectal balloon (filled with 40 mL air) were performed at the start (t(0)), middle (t(mi)), and end of treatment (t(e)), resulting in 6 CT scans for each patient. Prostate displacement was measured from a lateral beam's-eye-view. DVHs of rectum as a solid organ, and anterior, posterior, and whole rectum wall were calculated at t(0), t(mi), and t(e), and variations during treatment were analyzed for both examinations, with and without balloon. Results: By use of the balloon, rectum filling variations (p = 0.04) and maximum anterior-posterior displacements of the prostate (p = 0.008) were reduced significantly, leading to a reduction in DVH variations during treatment. Maximum displacements of posterior prostate border (>5 mm) were found in 8/10 patients without a rectum balloon and in only 2/10 patients with the balloon. The balloon led to a significant reduction in partial posterior rectal wall volumes included in the high-dose regions, without significant changes at the anterior rectum wall in cases of irradiation of the prostate only. However, when entirely irradiating the whole seminal vesicles, this advantage was lost. Conclusions: The rectal balloon catheter represents a simple technique to immobilize the prostate and to determine the position of the anterior rectal wall at daily treatment. This allows a reduction of margins, because of reduced prostate movement during treatment course. (C) 2002 Elsevier Science Inc.
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significance of a rectal balloon as internal Immobilization Device in conformal radiotherapy of prostatic carcinoma
Strahlentherapie Und Onkologie, 1999Co-Authors: Natascha Gerstne, Stefa Wachte, Daniela Dorne, Grego Goldne, Adriana Colotto, Richard PotteAbstract:BACKGROUND As known from the literature, prostate motion depends on different bladder and/or rectum fillings. The aim of this study was to analyze the influence of a rectum balloon catheter, used as an internal Immobilization Device, on prostate and rectum motion during the treatment course. Moreover we have analyzed if the balloon enables an increase of the distance between the prostate and the posterior rectum wall. PATIENTS AND METHODS Ten patients with localized prostate cancer (T1 to T3) underwent computed tomographic examinations with and without rectal balloon (filled with 40 ml air) at 3 times during treatment course (at the start, middle and end of treatment). Edges of prostate, rectum and bladder were measured in relation to bony reference structures and compared for both examination series (with and without balloon). RESULTS An increase of the distance between the prostate and the posterior rectal wall of 8 mm was observed at the base of the prostate when using the rectum balloon (Figures 1a,b and 2). Moreover prostate motion in the ventrodorsal direction > or = 4 mm (1 SD) was reduced from 6/10 patients (60%) to 1/10 patients (10%) using the rectal balloon (Table 3, Figure 3). In general, deviations in the latero-lateral and cranio-caudal directions were less (mean < or = 2 mm, 1 SD), no difference between both examination series (with and without balloon) was observed. CONCLUSION Rectal balloon catheter offers a possibility to reduce prostate motion and rectum filling variations during treatment course. In addition it enables an increase in the distance between prostate and posterior rectal wall, which could enable an improved protection of the posterior rectal wall.
Stefa Wachte - One of the best experts on this subject based on the ideXlab platform.
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the influence of a rectal balloon tube as internal Immobilization Device on variations of volumes and dose volume histograms during treatment course of conformal radiotherapy for prostate cancer
International Journal of Radiation Oncology Biology Physics, 2002Co-Authors: Stefa Wachte, Natascha Gerstne, Daniela Dorne, Grego Goldne, Adriana Colotto, Andre Wambersie, Richard PotteAbstract:Purpose: A prospective comparative study of a subset of 10 consecutive patients was performed, to describe the effects of an air-inflated rectal balloon tube that has been used for prostate Immobilization in 360 patients since 1994. In particular, influences on prostate motion, rectum filling variations, and dose-volume histograms (DVHs) of the rectum during a course of conformal radiotherapy were investigated. Methods and Materials: Computed tomographic (CT) examinations without and with rectal balloon (filled with 40 mL air) were performed at the start (t(0)), middle (t(mi)), and end of treatment (t(e)), resulting in 6 CT scans for each patient. Prostate displacement was measured from a lateral beam's-eye-view. DVHs of rectum as a solid organ, and anterior, posterior, and whole rectum wall were calculated at t(0), t(mi), and t(e), and variations during treatment were analyzed for both examinations, with and without balloon. Results: By use of the balloon, rectum filling variations (p = 0.04) and maximum anterior-posterior displacements of the prostate (p = 0.008) were reduced significantly, leading to a reduction in DVH variations during treatment. Maximum displacements of posterior prostate border (>5 mm) were found in 8/10 patients without a rectum balloon and in only 2/10 patients with the balloon. The balloon led to a significant reduction in partial posterior rectal wall volumes included in the high-dose regions, without significant changes at the anterior rectum wall in cases of irradiation of the prostate only. However, when entirely irradiating the whole seminal vesicles, this advantage was lost. Conclusions: The rectal balloon catheter represents a simple technique to immobilize the prostate and to determine the position of the anterior rectal wall at daily treatment. This allows a reduction of margins, because of reduced prostate movement during treatment course. (C) 2002 Elsevier Science Inc.
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significance of a rectal balloon as internal Immobilization Device in conformal radiotherapy of prostatic carcinoma
Strahlentherapie Und Onkologie, 1999Co-Authors: Natascha Gerstne, Stefa Wachte, Daniela Dorne, Grego Goldne, Adriana Colotto, Richard PotteAbstract:BACKGROUND As known from the literature, prostate motion depends on different bladder and/or rectum fillings. The aim of this study was to analyze the influence of a rectum balloon catheter, used as an internal Immobilization Device, on prostate and rectum motion during the treatment course. Moreover we have analyzed if the balloon enables an increase of the distance between the prostate and the posterior rectum wall. PATIENTS AND METHODS Ten patients with localized prostate cancer (T1 to T3) underwent computed tomographic examinations with and without rectal balloon (filled with 40 ml air) at 3 times during treatment course (at the start, middle and end of treatment). Edges of prostate, rectum and bladder were measured in relation to bony reference structures and compared for both examination series (with and without balloon). RESULTS An increase of the distance between the prostate and the posterior rectal wall of 8 mm was observed at the base of the prostate when using the rectum balloon (Figures 1a,b and 2). Moreover prostate motion in the ventrodorsal direction > or = 4 mm (1 SD) was reduced from 6/10 patients (60%) to 1/10 patients (10%) using the rectal balloon (Table 3, Figure 3). In general, deviations in the latero-lateral and cranio-caudal directions were less (mean < or = 2 mm, 1 SD), no difference between both examination series (with and without balloon) was observed. CONCLUSION Rectal balloon catheter offers a possibility to reduce prostate motion and rectum filling variations during treatment course. In addition it enables an increase in the distance between prostate and posterior rectal wall, which could enable an improved protection of the posterior rectal wall.
Natascha Gerstne - One of the best experts on this subject based on the ideXlab platform.
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the influence of a rectal balloon tube as internal Immobilization Device on variations of volumes and dose volume histograms during treatment course of conformal radiotherapy for prostate cancer
International Journal of Radiation Oncology Biology Physics, 2002Co-Authors: Stefa Wachte, Natascha Gerstne, Daniela Dorne, Grego Goldne, Adriana Colotto, Andre Wambersie, Richard PotteAbstract:Purpose: A prospective comparative study of a subset of 10 consecutive patients was performed, to describe the effects of an air-inflated rectal balloon tube that has been used for prostate Immobilization in 360 patients since 1994. In particular, influences on prostate motion, rectum filling variations, and dose-volume histograms (DVHs) of the rectum during a course of conformal radiotherapy were investigated. Methods and Materials: Computed tomographic (CT) examinations without and with rectal balloon (filled with 40 mL air) were performed at the start (t(0)), middle (t(mi)), and end of treatment (t(e)), resulting in 6 CT scans for each patient. Prostate displacement was measured from a lateral beam's-eye-view. DVHs of rectum as a solid organ, and anterior, posterior, and whole rectum wall were calculated at t(0), t(mi), and t(e), and variations during treatment were analyzed for both examinations, with and without balloon. Results: By use of the balloon, rectum filling variations (p = 0.04) and maximum anterior-posterior displacements of the prostate (p = 0.008) were reduced significantly, leading to a reduction in DVH variations during treatment. Maximum displacements of posterior prostate border (>5 mm) were found in 8/10 patients without a rectum balloon and in only 2/10 patients with the balloon. The balloon led to a significant reduction in partial posterior rectal wall volumes included in the high-dose regions, without significant changes at the anterior rectum wall in cases of irradiation of the prostate only. However, when entirely irradiating the whole seminal vesicles, this advantage was lost. Conclusions: The rectal balloon catheter represents a simple technique to immobilize the prostate and to determine the position of the anterior rectal wall at daily treatment. This allows a reduction of margins, because of reduced prostate movement during treatment course. (C) 2002 Elsevier Science Inc.
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significance of a rectal balloon as internal Immobilization Device in conformal radiotherapy of prostatic carcinoma
Strahlentherapie Und Onkologie, 1999Co-Authors: Natascha Gerstne, Stefa Wachte, Daniela Dorne, Grego Goldne, Adriana Colotto, Richard PotteAbstract:BACKGROUND As known from the literature, prostate motion depends on different bladder and/or rectum fillings. The aim of this study was to analyze the influence of a rectum balloon catheter, used as an internal Immobilization Device, on prostate and rectum motion during the treatment course. Moreover we have analyzed if the balloon enables an increase of the distance between the prostate and the posterior rectum wall. PATIENTS AND METHODS Ten patients with localized prostate cancer (T1 to T3) underwent computed tomographic examinations with and without rectal balloon (filled with 40 ml air) at 3 times during treatment course (at the start, middle and end of treatment). Edges of prostate, rectum and bladder were measured in relation to bony reference structures and compared for both examination series (with and without balloon). RESULTS An increase of the distance between the prostate and the posterior rectal wall of 8 mm was observed at the base of the prostate when using the rectum balloon (Figures 1a,b and 2). Moreover prostate motion in the ventrodorsal direction > or = 4 mm (1 SD) was reduced from 6/10 patients (60%) to 1/10 patients (10%) using the rectal balloon (Table 3, Figure 3). In general, deviations in the latero-lateral and cranio-caudal directions were less (mean < or = 2 mm, 1 SD), no difference between both examination series (with and without balloon) was observed. CONCLUSION Rectal balloon catheter offers a possibility to reduce prostate motion and rectum filling variations during treatment course. In addition it enables an increase in the distance between prostate and posterior rectal wall, which could enable an improved protection of the posterior rectal wall.
Ia E Utle - One of the best experts on this subject based on the ideXlab platform.
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the use of rectal balloon during the delivery of intensity modulated radiotherapy imrt for prostate cancer more than just a prostate gland Immobilization Device
Cancer Journal, 2002Co-Authors: I S Teh, Joh E Mcgary, L Dong, Wei Yua Mai, Steve L Carpente, Kam J Chiu, Shiao Y Woo, W H Gra, Ia E UtleAbstract:Purpose The purpose of this study was to investigate the role of a rectal balloon for prostate Immobilization and rectal toxicity reduction in patients receiving dose-escalated intensity-modulated radiotherapy for prostate cancer. Patients and methods Patients with localized prostate cancer who were undergoing intensity-modulated radiotherapy were treated in a prone position, immobilized with a customized Vac-Lok bag (MED-TEC, Orange City, IA). A rectal balloon with 100 cc of air was used to immobilize the prostate. The prostate displacements were measured using computed tomography (CT)-CT fusion on 10 patients who received radioactive seed implant before intensity-modulated radiotherapy. They were scanned twice weekly during 5 weeks of intensity-modulated radiotherapy, and breathing studies were also performed. Rectal toxicity was evaluated by use of Radiation Therapy Oncology Group scoring in 100 patients. They were treated to a mean dose of 76 Gy over 35 fractions (2.17-Gy fraction size). Dose-volume histogram of the rectum was assessed. A film phantom was constructed to simulate the 4-cm diameter air cavity that was created by the rectal balloon. Kodak XV2 films (Rochester NY) were used to measure and compare dose distribution with and without the air cavity. A fraction of 1.25 Gy was delivered to the phantom at isocenter with 15-MV photons by use of the NOMOS Peacock system and the MIMiC treatment delivery system (Sewickley, PA). Results The anterior-posterior and lateral prostate displacements were minimal, on the order of measurement uncertainty (approximately 1 mm). The standard deviation of superior-inferior displacement was 1.78 mm. Breathing studies showed no organ displacement during normal breathing when the rectal balloon was in place. The rectal toxicity profile was very favorable: 83% (83/100) patients had no rectal complaint, and 11% and 6% had grade 1 and 2 toxicity, respectively. Dose-volume histogram analysis revealed that in all of the patients, no more than 25% of the rectum received 70 Gy or greater. As visualized by film dosimetry, the dose at air-tissue interface was approximately 15% lower than that without an air cavity. The dose built up rapidly so that at 1 and 2 mm, the differential was approximately 8% and 5%, respectively. The dosimetric coverage at the depth of the posterior prostate wall was essentially equal, with or without the air cavity. Discussion The use of a rectal balloon during intensity-modulated radiotherapy significantly reduces prostate motion. Prostate Immobilization thus allows a safer and smaller planning target volume margin. It has also helped spare the anterior rectal wall (by its dosimetric effects) and reduced the rectal volume that received high-dose radiation (by rectal wall distension). All these factors may have further contributed to the decreased rectal toxicity achieved by intensity-modulated radiotherapy, despite dose escalation and higher-than-conventional fraction size.
L Dong - One of the best experts on this subject based on the ideXlab platform.
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the use of rectal balloon during the delivery of intensity modulated radiotherapy imrt for prostate cancer more than just a prostate gland Immobilization Device
Cancer Journal, 2002Co-Authors: I S Teh, Joh E Mcgary, L Dong, Wei Yua Mai, Steve L Carpente, Kam J Chiu, Shiao Y Woo, W H Gra, Ia E UtleAbstract:Purpose The purpose of this study was to investigate the role of a rectal balloon for prostate Immobilization and rectal toxicity reduction in patients receiving dose-escalated intensity-modulated radiotherapy for prostate cancer. Patients and methods Patients with localized prostate cancer who were undergoing intensity-modulated radiotherapy were treated in a prone position, immobilized with a customized Vac-Lok bag (MED-TEC, Orange City, IA). A rectal balloon with 100 cc of air was used to immobilize the prostate. The prostate displacements were measured using computed tomography (CT)-CT fusion on 10 patients who received radioactive seed implant before intensity-modulated radiotherapy. They were scanned twice weekly during 5 weeks of intensity-modulated radiotherapy, and breathing studies were also performed. Rectal toxicity was evaluated by use of Radiation Therapy Oncology Group scoring in 100 patients. They were treated to a mean dose of 76 Gy over 35 fractions (2.17-Gy fraction size). Dose-volume histogram of the rectum was assessed. A film phantom was constructed to simulate the 4-cm diameter air cavity that was created by the rectal balloon. Kodak XV2 films (Rochester NY) were used to measure and compare dose distribution with and without the air cavity. A fraction of 1.25 Gy was delivered to the phantom at isocenter with 15-MV photons by use of the NOMOS Peacock system and the MIMiC treatment delivery system (Sewickley, PA). Results The anterior-posterior and lateral prostate displacements were minimal, on the order of measurement uncertainty (approximately 1 mm). The standard deviation of superior-inferior displacement was 1.78 mm. Breathing studies showed no organ displacement during normal breathing when the rectal balloon was in place. The rectal toxicity profile was very favorable: 83% (83/100) patients had no rectal complaint, and 11% and 6% had grade 1 and 2 toxicity, respectively. Dose-volume histogram analysis revealed that in all of the patients, no more than 25% of the rectum received 70 Gy or greater. As visualized by film dosimetry, the dose at air-tissue interface was approximately 15% lower than that without an air cavity. The dose built up rapidly so that at 1 and 2 mm, the differential was approximately 8% and 5%, respectively. The dosimetric coverage at the depth of the posterior prostate wall was essentially equal, with or without the air cavity. Discussion The use of a rectal balloon during intensity-modulated radiotherapy significantly reduces prostate motion. Prostate Immobilization thus allows a safer and smaller planning target volume margin. It has also helped spare the anterior rectal wall (by its dosimetric effects) and reduced the rectal volume that received high-dose radiation (by rectal wall distension). All these factors may have further contributed to the decreased rectal toxicity achieved by intensity-modulated radiotherapy, despite dose escalation and higher-than-conventional fraction size.
