• The Journal of Korean Society for Radiation Therapy
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• v.11 no.1
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• pp.33-37
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• 1999

• 대한방사선치료학회:학술대회논문집
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• 1999.05a
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• pp.12-13
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• 1999

• Radiation Oncology Journal
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• v.15 no.3
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• pp.263-268
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• 1997

Purpose : Authors designed a customized Small Bowel Displacement System (SBDS) to displace the small bowel from the Pelvic radiation fields and minimize treatment-related bowel morbidities. Materials and Methods : From August 1995 to Mar 1996. 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized styrofoam compression device which can displace the small bowel from the radiation fields and an individualized immobilization abdominal board for easy daily setup in prone position After opacifying the small bowel with Barium3, the patients were laid Prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The areas of the small bowel included in the radiation fields with and without the SBDS were compared. Results : Using the SBDS, the mean small bowel area was reduced by $59\%;on\;PA\;and\;51\%$ on LAT films (P=0.0001). In six Patients (6/55. $11\%$), it was Possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Only $15\%$ (8/55) of patients treated with the SBDS manifested diarrhea requiring medication. Conclusion : The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and reduce the radiation therapy morbidities. Compliance with setup is excellent when the SBDS is used.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.7-12
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• 2019

Purpose: During the pelvic radiation therapy, it is performed with controlling bladder volume because the range of irradiation is changed depending on the bladder volume. Therefore in this study, we evaluate the accuracy of BVI by tracing the change of bladder volume using ultrasonic pulse diagnosis equipment(BVI 6100, Medical supply Co. LTD) Material and Methods: From January 2017 to September 2018, 19 patients who received pelvic radiation therapy at Pusan National University Hospital were included. To treat the patient, we compared that the bladder volume obtained from the BVI and the bladder volume obtained from the CBCT image then we evaluated for significance. Results: There was a significant correlation of r=0.773, BVI and CBCT in the whole volume section. However, based on the bladder volume in the RTP Image the p value was shown to be 0 at 125~175cc and lower than 0.05 at 175~275cc, And more than 0.05 at 275~375cc. Conclusions: In this study, the patient whose bladder volume is above than 275cc, there is a significance of bladder volume between BVI and CBCT image. However, we could make a decision to be undermined the reliability of BVI measurement in the case of the patient with emptied his urine. Therefore, it is possible to acquire a significant value for 175~275cc patients to use the correction value of BVI and the appropriate tolerance of volume.

• The Journal of Korean Society for Radiation Therapy
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• v.31 no.2
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• pp.65-74
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• 2019

Purpose: Recently, A Catcher was added to prevent sagging in Radixact^® X9. In this study, We quantitatively compared general couch of Tomo-HDA^® with catcher couch of Radixact^® X9 using the human phantom and evaluated usefulness of catcher. Materials and methods: We used rando phantom for phantom study and set the each iso-center of head and neck region and Pelvis region for region parameter. Furthermore, We used hand made low melting point alloys for weight parameter. MVCT(Mega Voltage Computed Tomography) images were acquired for vertical error and rotation(pitch) error measurement increasing weight(A: 15kg, A+B: 30kg, A+B+C: 45kg). We selected 120 patients who has been treated using Tomotherpy machine for patient study. 60 patients has been treated in Tomo-HDA^® and the other 60 patients treated in Radixact^® X9. In the patient study methods, vertical error and rotation(pitch) error was measured for mean value calculation using MVCT images acquired on first day of radiation therapy. Result: Result of phantom study, Vertical error and rotation(pitch) error was increased proportionally increased as the weight increases in general couch of Tomo-HDA^®. each maximum value was 7.52mm, 0.38° in head and neck region and 11.94mm, 0.92° in pelvis region. However, We could confirm that there was stable error range(0.02~0.1mm, 0~0.04°) in Catcher couch of Radixact^®. Result of patient study, The head and neck region was measured 4.79mm 0.33° lower, and the pelvis region was measured 7.66mm, 0.22° lower in Catcher couch of Radixact^® X9. Conclusion: In this study, Vertical error and rotation(pitch) error was proportionally increased as the weight increases in general couch of Tomo-HDA^®. Especially, The pelvis region error was more increased than the head and neck region error. However, Vertical error and rotation(pitch) error was regularly generated regardless of weight or regions in Catcher^TM couch of Radixact^® X9 that this study's purpose. In conclusion, Catcher^TM couch of Radixact^® X9 can minimize mechanical error that couch sagging. Furthermore, The pelvis region is more efficiency than head and neck region. In radiation therapy using Tomotherapy machine, it is regarded that may contribute to minimizing unadjusted pitch error due to characters of Tomotherapy.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.1
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• pp.43-49
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• 2007

Purpose: The aim of this study was the clinical implementation of IGRT using KV CBCT for setup correction in radiation therapy. Materials and Methods: We selected 9 patients (3 patient for each region; head, body, pelvis)and acquired 135 CBCT images with CLINAC iX (Varian medical system, USA). During the scan, the required time was measured. We analyzed the result in 3 direction; vertical, longitudinal, lateral. Results: The mean setup errors at the couch position of vertical, lateral, and longitudinal direction were 0.07, 0.12, and 0.1 cm in the head region, 0.3, 0.26, and 0.22 cm in the body region, 0.21, 0.18, and 0.15 cm in the pelvis region respectively. The mean time required for CBCT was $6{\sim}7$ minute. Conclusion: The CBCT on the LINAC provides the capacity for soft tissue imaging in the treatment position and real time monitoring during treatment delivery. With presented workflow, the setup correction within reasonable time for more accurate radiation therapy is possible. And it's image can be very useful for adaptive radiation therapy(ART) in the future with improved image quality.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.379-385
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• 1997

Purpose : Ovarian dysgerminoma is a highly radiosensitive malignant tumor occurring in young age group. The conventional treatment was total abdominal hysterectomy and bilateral salpingo-oophorectomy followed by radiotherapy. We retrospectively analyzed the treatment results of Patients who had received radiotherapy in the era before chemotherapy was widely used. Material and Method : Twenty two patients with ovarian dysgerminoma were treated at the Department of Therapeutic Radiology, Seoul National University Hospital between August, 1980 and May, 1991. Four patients were excluded from this study, because three patients received incomplete treatment and one received combined chemotherapy. Sixteen patients received postoperative radiotherapy and two patients had radical radiotherapy as tumor was unresectable. Median follow-up period was 99 months (range, 51-178) Median age was 22 years (range, 11-42). Among the postoperatively treated patients, three Patients were in stage IA, eight in stage IC, two in stage II, and three in stage III. One patient had Turner's syndrome. Radiotherapy was performed with high energy photon (telecobalt unit or linear accelerator, either 6MV or 10MV), The radiation dose to the whole abdomen was 1950-2100cGy (median, 2000) and 1050-2520cGy was added to the whole pelvis, the total dose to the whole pelvis was 3000-4500cGy (median, 3500). Prophylactic Paraaortic area irradiation was done in six Patients (dose range, 900-1500cGy). One patient who had positive Paraaortic node, received radiation dose of 1620cGy, followed by additional 900cGy to the gross mass with shrinking field. Total dose to the paraaortic node was 4470cGy. Six patients, including one who had paraaortic node metastasis, received Prophylactic irradiation to mediastinum and supraclavicular area (2520cGy). Of the two patients with unresectable tumors who received radical radiotherapy, one was in stage III and the other was in stage IV with left supraclavicular lymph node metastasis. The stage III patient received radiation to the whole abdomen (2000cGy), followed by boost to whole pelvis (2070cGy) and paraaortic area (2450cGy). Stage IV patient received radiation to the whole abdomen (2000cGy), followed by radiation to the whole pelvis and paraaortic area (2400cGy), mediastinum (2520cGy) , and left supraclavicular area (3550cGy) .Results : The 5 year local control rate was $100\%$ in patients who received postoperative adiuvant radiotherapy after total abdominal hysterectomy and bilateral salpingo-oophorectomy. Only one patient in stage III who did not receive prophylactic irradiation to mediastinum developed mediastinal metastasis. but was salvaged by chemotherapy. So. the 5 year overall survival rate uras also $100\%$. Two patients who received radiation only, are alive without disease at 112 and 155 months. Conclusion : Postoperntive adjuvant radiotherapy as well as radical radiotherapy in unresectable ovarian dysgerminoma was very effective. aut chemotherapy is also an effective treatment modality We now recomrneifd chemotherapy for Patients who need to save their ovarian functien and reserve radiotherapv fov chemo-resistant tumor or recurrence alter che motherapy.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.185-189
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• 2018

Purpose : We evaluated the quality of life satisfaction of patients with radiation therapy while maintaining the set-up line. Materials and Methods : We retrospectively reviewed 60 patients who visited our clinic in January, 2018. The most common complaint was the inconvenience of not being able to wash during treatment (64 %), and a surgical tape was placed on the Set-up Line to help patients wash during the treatment period. A total of 50 patients who underwent surgical tape were evaluated on a 5-point scale (1 point was very unsatisfactory, 2 points were unsatisfactory, 3 points were average, 4 points were satisfied, 5 points were very satisfied). Forty patients out of 50 responded to the first treatment, and 10 patients underwent treatment. Results : In the first survey, 68 % of the patients and 32 % of the males were aged 34 %, 50~60 % and 38 %, respectively. Treatment areas were breast (57 %), chest (13 %), pelvis (10 %). The results of the second questionnaire after applying the surgical tape showed that 25 of the 40 patients and 15 of the male patients were treated. The treatment area was 22 breast and 18 pelvic areas. In the satisfaction of the 5-point scale, 5 to 15 points were satisfied with 1-3 points, and 4-5 points with 35 points (1 point 2 points, 2 points 2 points, 3 point 1 points, 4 point points 17 point points, % And 43 %, respectively. The results of the questionnaire survey of patients who were applied during the treatment showed that 9 out of 10 women and 1 male were treated. The treatment area was 8 breast and 2 pelvic areas. One point was satisfied with one point, and five points with nine points were satisfied with 90 %. Conclusions : The importance of improving the quality of life of patients with cancer is also important. After applying the surgical tape, 88 % of the patients who started the treatment and 90 % of the patients who applied during the treatment were satisfied. Particularly, patients who applied during treatment showed higher satisfaction. If this is not possible for all patients, selective application to patients with discomfort will be helpful in improving the quality of life of cancer patients.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.99-106
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• 2011

Purpose: To analyze our quality assurance (QA) data for intensity modulated radiation therapy (IMRT) according to treatment site and to possibly improve QA for IMRT in Hospital. Materials and Methods: We performed QA on 50 patients (head and neck, 28 patients; Breast, 14 patients; Pelvis, 8 patients) for IMRT. The calculated dose from RTP was compared with the measured value film, gamma index, and ionization chamber for dose measurement in each case. Results: The point dose measurement results in 45 of 50 patients showed good agreement with the calculation dose (${\pm}3%$). The largest error measured thus far has been 3.60%, with a mean of only -0.17% (SD, 2.25%). Each treatment site showed an error rate of -0.13% (SD, 1.93%) for head and neck cases, -0.26% (SD, 2.79%) for breast cases, and 0.24% (SD, 2.44%) for pelvis cases. The gamma index verified with the error rate of head and neck cases (6%), breast (10%), and pelvis (6%), which corresponded to a tolerance of 3 mm (3% for the head and neck, 2%, for the breast 1% for the pelvis, and 0% in the region where the isodose curve was greater than 90%. Conclusion: We recognize the cause of errors for each treatment site of IMRT QA and so we maximize our efforts to reduce error and increase accuracy.

• The Journal of Korean Society for Radiation Therapy
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• v.26 no.1
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• pp.37-42
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• 2014

Purpose : At the time of the pelvis cancer radiation treatment using the belly board, set-up error is large because of a prone position. In order to improve the reproducibility, we made Vac-lock type belly board. In this study, we attempt to validate its utility. Materials and Methods : We compared belly board and Vac-lock type belly board through the OBI. OBI was performed three times with entire course of treatment and the setup errors in the direction of X axis, Y axis, Z axis were recorded and calculated the distance from the isocenter. Results : X axis, Y axis, Z axis setup errors with existing belly board were 0.32 cm, 0.41 cm, 0.29 cm. The setup errors with the vac-lock type belly board were 0.12 cm, 0.19 cm, 0.17 cm. Further, errors of 0~0.29 cm were increased from 48% to 83% when using VLT belly board. Error of 0.5 cm or more was reduced from 21% to 2%. Conclusion : Vac-lock type belly board is able to maintain the efficacy of existing and create to match the characteristics of the patient. Therefore We think that vac-lock type belly board is very useful in pelvic cancer patients.