Objective: This study was to compare this multiple-field conformal technique to the 2-dimensional (2D) conventional technique with respect to target volume coverage and dose to normal tissues. Methods: We conducted a ...Objective: This study was to compare this multiple-field conformal technique to the 2-dimensional (2D) conventional technique with respect to target volume coverage and dose to normal tissues. Methods: We conducted a single institutional prospective comparative dosimetric analysis of 15 patients who received radical radiation therapy for bladder cancer presented to Radiotherapy Department in National Cancer Institute, Cairo (Egypt), in period between November 2011 to July 2012 using 3-dimensional (3D) conformal radiotherapy technique for each patient, a second 2D conventional radiotherapy treatment plan was done, the two techniques were then compared using dose volume histogram (DVH) analysis. Results: Comparing different DVHs, it was found that the planning target volume (PTV) was adequately covered in both (3D & 2D) plans while it was demonstrated that this multiple field conformal technique produced superior distribution compared to 2D technique, with considerable sparing of rectum and to lesser extent for the head of both femora. Conclusion: From the present study, it is recommended to use 3D planning for cases of bladder cancer especially in elderly patients as it produces good coverage of the target volume as well as good sparing of the surrounding critical organs.展开更多
Adjacent treatment fields are commonly employed in external beam radiation therapy, such as the mantle and inverted-Y fields for the treatment of Hodgkin's disease. In some cases, the adjacent fields are orthogona...Adjacent treatment fields are commonly employed in external beam radiation therapy, such as the mantle and inverted-Y fields for the treatment of Hodgkin's disease. In some cases, the adjacent fields are orthogonal, such as the craniospinal fields used in the treatment of medulloblastoma. Another example is the irradiation of head and neck tumors when the lateral neck fields are placed adjacent to the anterior supraclavicular field. In each of these situations, there is a possibility of introducing very large dosage errors across the junction. Consequently, this region is at risk for tumor recurrence if it is underdosed or severe complications if it is overdosed. Four millimeter overlap and gap resulted in an unacceptable dose in homogeneity in the junction. As a result of this study, the magnitudes of hot and cold spots might be clinically acceptable for 3 mm gap between photon fields.展开更多
Objective:This study was to compare this multiple-field conformal technique to the AP-PA technique with respect to target volume coverage and dose to normal tissues.Methods:We conducted a single institutional prospect...Objective:This study was to compare this multiple-field conformal technique to the AP-PA technique with respect to target volume coverage and dose to normal tissues.Methods:We conducted a single institutional prospective comparative dosimetric analysis of 22 patients who received neoadjuvant radiation therapy for rectal cancer presented to radiotherapy department in National Cancer Institute,Cairo in period between June 2010 to September 2011 using 3D conformal radiotherapy technique for each patient,a second radiotherapy treatment plan was done using an anteroposterior (AP-PA) fields,the two techniques were then compared using dose volume histogram (DVH) analysis.Results:Comparing different DVHs,it was found that the planning target volume (PTV) was adequately covered in both (3D & 2D) plans while it was demonstrates that this multiple field conformal technique produces superior distribution compared to 2D technique,with considerable sparing of bladder,ovaries and head of both femora.Conclusion:From the present study,it shows that it is recommended to use 3D planning for preoperative cases of cancer rectum so far it produces good coverage of the target as well as good sparing of the surrounding critical organs.展开更多
Objective： Of this study was to compare this multiple-field conformal technique to the AP-PA technique with re- spect to target volume coverage and dose to normal tissues. Methods： Seventeen patients with stages Ⅱ-...Objective： Of this study was to compare this multiple-field conformal technique to the AP-PA technique with re- spect to target volume coverage and dose to normal tissues. Methods： Seventeen patients with stages Ⅱ-Ⅲ denocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy presented to radiotherapy department in National Cancer Institute, Cairo in period between February 2009 to March 2010 using 3D conformal radiotherapy technique that consisted of a monoisocentric arrangement Employing 4-6 radiation fields. For each patient, a second radiotherapy treatment plan was generated utilizing AP-PA fields, the two techniques were then compared for target volume coverage and dose to normal tissues using dose volume histogram （DVH） analysis. Results： The planning target volume （PTV） was adequately covered in both （ 3D ＆ 2D ） plans, comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the conformal technique especially for left kidney ＆ spinal cord, but the liver doses is higher but still well below liver tolerance. Conclusion： 3D conformal radiotherapy produced reduced radiation doses to the kidneys （especially left kidney ＆ spinal cord） compared to AP-PA techniques, with the potential to reduce treatment toxicity.展开更多
<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity M...<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for </span><span style="font-family:Verdana;">the </span><span "=""><span style="font-family:Verdana;">treatment of malignant gliomas. </span><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">methods:</span></b><span style="font-family:Verdana;"> We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine w</span><span style="font-family:Verdana;">h</span><span style="font-family:Verdana;">ich techn</span><span style="font-family:Verdana;">ology</span><span "=""><span style="font-family:Verdana;"> improves significantly dosimetric parameters. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">dose to the PTV while sparing OARs optimally.</span> </div>展开更多
文摘Objective: This study was to compare this multiple-field conformal technique to the 2-dimensional (2D) conventional technique with respect to target volume coverage and dose to normal tissues. Methods: We conducted a single institutional prospective comparative dosimetric analysis of 15 patients who received radical radiation therapy for bladder cancer presented to Radiotherapy Department in National Cancer Institute, Cairo (Egypt), in period between November 2011 to July 2012 using 3-dimensional (3D) conformal radiotherapy technique for each patient, a second 2D conventional radiotherapy treatment plan was done, the two techniques were then compared using dose volume histogram (DVH) analysis. Results: Comparing different DVHs, it was found that the planning target volume (PTV) was adequately covered in both (3D & 2D) plans while it was demonstrated that this multiple field conformal technique produced superior distribution compared to 2D technique, with considerable sparing of rectum and to lesser extent for the head of both femora. Conclusion: From the present study, it is recommended to use 3D planning for cases of bladder cancer especially in elderly patients as it produces good coverage of the target volume as well as good sparing of the surrounding critical organs.
文摘Adjacent treatment fields are commonly employed in external beam radiation therapy, such as the mantle and inverted-Y fields for the treatment of Hodgkin's disease. In some cases, the adjacent fields are orthogonal, such as the craniospinal fields used in the treatment of medulloblastoma. Another example is the irradiation of head and neck tumors when the lateral neck fields are placed adjacent to the anterior supraclavicular field. In each of these situations, there is a possibility of introducing very large dosage errors across the junction. Consequently, this region is at risk for tumor recurrence if it is underdosed or severe complications if it is overdosed. Four millimeter overlap and gap resulted in an unacceptable dose in homogeneity in the junction. As a result of this study, the magnitudes of hot and cold spots might be clinically acceptable for 3 mm gap between photon fields.
文摘Objective:This study was to compare this multiple-field conformal technique to the AP-PA technique with respect to target volume coverage and dose to normal tissues.Methods:We conducted a single institutional prospective comparative dosimetric analysis of 22 patients who received neoadjuvant radiation therapy for rectal cancer presented to radiotherapy department in National Cancer Institute,Cairo in period between June 2010 to September 2011 using 3D conformal radiotherapy technique for each patient,a second radiotherapy treatment plan was done using an anteroposterior (AP-PA) fields,the two techniques were then compared using dose volume histogram (DVH) analysis.Results:Comparing different DVHs,it was found that the planning target volume (PTV) was adequately covered in both (3D & 2D) plans while it was demonstrates that this multiple field conformal technique produces superior distribution compared to 2D technique,with considerable sparing of bladder,ovaries and head of both femora.Conclusion:From the present study,it shows that it is recommended to use 3D planning for preoperative cases of cancer rectum so far it produces good coverage of the target as well as good sparing of the surrounding critical organs.
文摘Objective： Of this study was to compare this multiple-field conformal technique to the AP-PA technique with re- spect to target volume coverage and dose to normal tissues. Methods： Seventeen patients with stages Ⅱ-Ⅲ denocarcinoma of the stomach were treated with adjuvant postoperative chemoradiotherapy presented to radiotherapy department in National Cancer Institute, Cairo in period between February 2009 to March 2010 using 3D conformal radiotherapy technique that consisted of a monoisocentric arrangement Employing 4-6 radiation fields. For each patient, a second radiotherapy treatment plan was generated utilizing AP-PA fields, the two techniques were then compared for target volume coverage and dose to normal tissues using dose volume histogram （DVH） analysis. Results： The planning target volume （PTV） was adequately covered in both （ 3D ＆ 2D ） plans, comparative DVHs for the right kidney, left kidney and spinal cord demonstrate lower radiation doses using the conformal technique especially for left kidney ＆ spinal cord, but the liver doses is higher but still well below liver tolerance. Conclusion： 3D conformal radiotherapy produced reduced radiation doses to the kidneys （especially left kidney ＆ spinal cord） compared to AP-PA techniques, with the potential to reduce treatment toxicity.
文摘<div style="text-align:justify;"> <strong><span style="font-family:Verdana;">Background:</span></strong><span style="font-family:Verdana;"> Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for </span><span style="font-family:Verdana;">the </span><span "=""><span style="font-family:Verdana;">treatment of malignant gliomas. </span><b><span style="font-family:Verdana;">Materials</span></b> <b><span style="font-family:Verdana;">and</span></b> <b><span style="font-family:Verdana;">methods:</span></b><span style="font-family:Verdana;"> We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post</span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine w</span><span style="font-family:Verdana;">h</span><span style="font-family:Verdana;">ich techn</span><span style="font-family:Verdana;">ology</span><span "=""><span style="font-family:Verdana;"> improves significantly dosimetric parameters. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">dose to the PTV while sparing OARs optimally.</span> </div>
