1.Chronic Functional Constipation
Jeong Eun SHIN ; Kyung Sik PARK ; Kwangwoo NAM
The Korean Journal of Gastroenterology 2019;73(2):92-98
Constipation is a common functional problem of the digestive system and may occur secondary to diet, drugs, endocrine diseases, metabolic diseases, neurological diseases, psychiatric disorders, or gastrointestinal obstruction. When there is no secondary cause, constipation is diagnosed as functional constipation. The first steps that should be taken to relieve symptoms are diet and lifestyle modifications, and if unsuccessful, laxative therapy should be initiated. If a patient does not respond to laxative therapy, diagnostic anorectal physiological tests are performed, though they are not routinely recommended. However, these tests may be considered earlier in patients strongly suspected to have a defecatory disorder. The revised guideline on the diagnosis and treatment of chronic constipation will undoubtedly aid the individualized management of chronic constipation in clinical practice.
Biofeedback, Psychology
;
Constipation
;
Diagnosis
;
Diet
;
Digestive System
;
Digital Rectal Examination
;
Endocrine System Diseases
;
Humans
;
Laxatives
;
Life Style
;
Metabolic Diseases
2.Intra-Fractional Dose Evaluation for Patients with Breast Cancer Using Synthetic Computed Tomography
Sohyun AHN ; So Eun CHOI ; Jeong-Heon KIM ; Kwangwoo PARK ; Hai-Jeon YOON
Progress in Medical Physics 2024;35(4):145-154
Purpose:
This study investigated the use of synthetic computed tomography (CT) images derived from cone beam CT (CBCT) scans to analyze dose changes in breast cancer patients undergoing treatment and to evaluate the optimal timing for implementing adaptive radiotherapy.
Methods:
A retrospective analysis was conducted on five breast cancer patients treated with tomotherapy-based volumetric-modulated arc therapy at Yongin Severance Hospital. Each patient received 15 fractions, with doses of 320 centigray (cGy) to the high-dose planning target volume (PTV) and 267 cGy to the low-dose PTV. Planning CT images were acquired using the Aquilion scanner, andCBCT images were captured with the VersaHD linear accelerator’s on-board imager. These imageswere registered in RayStation using a hybrid deformable image registration method to generate synthetic CT images. Dose distributions were reanalyzed using the synthetic CT images, and dose-volume histogram parameters, including the dose to 95% of the volume (D95 ) and mean dose (Dmean ) for the PTV, as well as D95 , Dmean , the percentage of the volume receiving at least 5 Gy (V5 ) and 10 Gy (V10 )for organs-at-risk (OARs), were extracted using MATLAB to assess dose changes during treatment.
Results:
For the original plans, the mean D95 for PTV high across all patients was 287.13±31.32cGy, while for PTV low, it was 245.53±6.21 cGy. In contrast, the adaptive plans yielded a mean D95of 298.17±12.37 cGy for PTV High and 247.25±4.23 cGy for PTV low. The ART Plan may lead to increased dose exposure in certain structures, such as the spinal cord, while providing targeted improvements in reducing radiation exposure in specific OARs (e.g., contralateral breast and esophagus).
Conclusions
Synthetic CT images generated from CBCT scans provide a fast and efficient means of quantifying dose changes, supporting precise patient care through interfractional evaluation.Future studies will aim to apply this method to other organs and larger patient cohorts.
4.Intra-Fractional Dose Evaluation for Patients with Breast Cancer Using Synthetic Computed Tomography
Sohyun AHN ; So Eun CHOI ; Jeong-Heon KIM ; Kwangwoo PARK ; Hai-Jeon YOON
Progress in Medical Physics 2024;35(4):145-154
Purpose:
This study investigated the use of synthetic computed tomography (CT) images derived from cone beam CT (CBCT) scans to analyze dose changes in breast cancer patients undergoing treatment and to evaluate the optimal timing for implementing adaptive radiotherapy.
Methods:
A retrospective analysis was conducted on five breast cancer patients treated with tomotherapy-based volumetric-modulated arc therapy at Yongin Severance Hospital. Each patient received 15 fractions, with doses of 320 centigray (cGy) to the high-dose planning target volume (PTV) and 267 cGy to the low-dose PTV. Planning CT images were acquired using the Aquilion scanner, andCBCT images were captured with the VersaHD linear accelerator’s on-board imager. These imageswere registered in RayStation using a hybrid deformable image registration method to generate synthetic CT images. Dose distributions were reanalyzed using the synthetic CT images, and dose-volume histogram parameters, including the dose to 95% of the volume (D95 ) and mean dose (Dmean ) for the PTV, as well as D95 , Dmean , the percentage of the volume receiving at least 5 Gy (V5 ) and 10 Gy (V10 )for organs-at-risk (OARs), were extracted using MATLAB to assess dose changes during treatment.
Results:
For the original plans, the mean D95 for PTV high across all patients was 287.13±31.32cGy, while for PTV low, it was 245.53±6.21 cGy. In contrast, the adaptive plans yielded a mean D95of 298.17±12.37 cGy for PTV High and 247.25±4.23 cGy for PTV low. The ART Plan may lead to increased dose exposure in certain structures, such as the spinal cord, while providing targeted improvements in reducing radiation exposure in specific OARs (e.g., contralateral breast and esophagus).
Conclusions
Synthetic CT images generated from CBCT scans provide a fast and efficient means of quantifying dose changes, supporting precise patient care through interfractional evaluation.Future studies will aim to apply this method to other organs and larger patient cohorts.
6.Intra-Fractional Dose Evaluation for Patients with Breast Cancer Using Synthetic Computed Tomography
Sohyun AHN ; So Eun CHOI ; Jeong-Heon KIM ; Kwangwoo PARK ; Hai-Jeon YOON
Progress in Medical Physics 2024;35(4):145-154
Purpose:
This study investigated the use of synthetic computed tomography (CT) images derived from cone beam CT (CBCT) scans to analyze dose changes in breast cancer patients undergoing treatment and to evaluate the optimal timing for implementing adaptive radiotherapy.
Methods:
A retrospective analysis was conducted on five breast cancer patients treated with tomotherapy-based volumetric-modulated arc therapy at Yongin Severance Hospital. Each patient received 15 fractions, with doses of 320 centigray (cGy) to the high-dose planning target volume (PTV) and 267 cGy to the low-dose PTV. Planning CT images were acquired using the Aquilion scanner, andCBCT images were captured with the VersaHD linear accelerator’s on-board imager. These imageswere registered in RayStation using a hybrid deformable image registration method to generate synthetic CT images. Dose distributions were reanalyzed using the synthetic CT images, and dose-volume histogram parameters, including the dose to 95% of the volume (D95 ) and mean dose (Dmean ) for the PTV, as well as D95 , Dmean , the percentage of the volume receiving at least 5 Gy (V5 ) and 10 Gy (V10 )for organs-at-risk (OARs), were extracted using MATLAB to assess dose changes during treatment.
Results:
For the original plans, the mean D95 for PTV high across all patients was 287.13±31.32cGy, while for PTV low, it was 245.53±6.21 cGy. In contrast, the adaptive plans yielded a mean D95of 298.17±12.37 cGy for PTV High and 247.25±4.23 cGy for PTV low. The ART Plan may lead to increased dose exposure in certain structures, such as the spinal cord, while providing targeted improvements in reducing radiation exposure in specific OARs (e.g., contralateral breast and esophagus).
Conclusions
Synthetic CT images generated from CBCT scans provide a fast and efficient means of quantifying dose changes, supporting precise patient care through interfractional evaluation.Future studies will aim to apply this method to other organs and larger patient cohorts.
8.Intra-Fractional Dose Evaluation for Patients with Breast Cancer Using Synthetic Computed Tomography
Sohyun AHN ; So Eun CHOI ; Jeong-Heon KIM ; Kwangwoo PARK ; Hai-Jeon YOON
Progress in Medical Physics 2024;35(4):145-154
Purpose:
This study investigated the use of synthetic computed tomography (CT) images derived from cone beam CT (CBCT) scans to analyze dose changes in breast cancer patients undergoing treatment and to evaluate the optimal timing for implementing adaptive radiotherapy.
Methods:
A retrospective analysis was conducted on five breast cancer patients treated with tomotherapy-based volumetric-modulated arc therapy at Yongin Severance Hospital. Each patient received 15 fractions, with doses of 320 centigray (cGy) to the high-dose planning target volume (PTV) and 267 cGy to the low-dose PTV. Planning CT images were acquired using the Aquilion scanner, andCBCT images were captured with the VersaHD linear accelerator’s on-board imager. These imageswere registered in RayStation using a hybrid deformable image registration method to generate synthetic CT images. Dose distributions were reanalyzed using the synthetic CT images, and dose-volume histogram parameters, including the dose to 95% of the volume (D95 ) and mean dose (Dmean ) for the PTV, as well as D95 , Dmean , the percentage of the volume receiving at least 5 Gy (V5 ) and 10 Gy (V10 )for organs-at-risk (OARs), were extracted using MATLAB to assess dose changes during treatment.
Results:
For the original plans, the mean D95 for PTV high across all patients was 287.13±31.32cGy, while for PTV low, it was 245.53±6.21 cGy. In contrast, the adaptive plans yielded a mean D95of 298.17±12.37 cGy for PTV High and 247.25±4.23 cGy for PTV low. The ART Plan may lead to increased dose exposure in certain structures, such as the spinal cord, while providing targeted improvements in reducing radiation exposure in specific OARs (e.g., contralateral breast and esophagus).
Conclusions
Synthetic CT images generated from CBCT scans provide a fast and efficient means of quantifying dose changes, supporting precise patient care through interfractional evaluation.Future studies will aim to apply this method to other organs and larger patient cohorts.
10.Intra-Fractional Dose Evaluation for Patients with Breast Cancer Using Synthetic Computed Tomography
Sohyun AHN ; So Eun CHOI ; Jeong-Heon KIM ; Kwangwoo PARK ; Hai-Jeon YOON
Progress in Medical Physics 2024;35(4):145-154
Purpose:
This study investigated the use of synthetic computed tomography (CT) images derived from cone beam CT (CBCT) scans to analyze dose changes in breast cancer patients undergoing treatment and to evaluate the optimal timing for implementing adaptive radiotherapy.
Methods:
A retrospective analysis was conducted on five breast cancer patients treated with tomotherapy-based volumetric-modulated arc therapy at Yongin Severance Hospital. Each patient received 15 fractions, with doses of 320 centigray (cGy) to the high-dose planning target volume (PTV) and 267 cGy to the low-dose PTV. Planning CT images were acquired using the Aquilion scanner, andCBCT images were captured with the VersaHD linear accelerator’s on-board imager. These imageswere registered in RayStation using a hybrid deformable image registration method to generate synthetic CT images. Dose distributions were reanalyzed using the synthetic CT images, and dose-volume histogram parameters, including the dose to 95% of the volume (D95 ) and mean dose (Dmean ) for the PTV, as well as D95 , Dmean , the percentage of the volume receiving at least 5 Gy (V5 ) and 10 Gy (V10 )for organs-at-risk (OARs), were extracted using MATLAB to assess dose changes during treatment.
Results:
For the original plans, the mean D95 for PTV high across all patients was 287.13±31.32cGy, while for PTV low, it was 245.53±6.21 cGy. In contrast, the adaptive plans yielded a mean D95of 298.17±12.37 cGy for PTV High and 247.25±4.23 cGy for PTV low. The ART Plan may lead to increased dose exposure in certain structures, such as the spinal cord, while providing targeted improvements in reducing radiation exposure in specific OARs (e.g., contralateral breast and esophagus).
Conclusions
Synthetic CT images generated from CBCT scans provide a fast and efficient means of quantifying dose changes, supporting precise patient care through interfractional evaluation.Future studies will aim to apply this method to other organs and larger patient cohorts.