• Title/Summary/Keyword: Patient radiation dose

Search Result 1,010, Processing Time 0.028 seconds

CdZnTe Detector for Computed Tomography based on Weighting Potential (가중 퍼텐셜에 기초한 CT용 CdZnTe 소자 설계)

  • Lim, Hyunjong;Park, Chansun;Kim, Jungsu;Kim, Jungmin;Choi, Jonghak;Kim, KiHyun
    • Journal of radiological science and technology
    • /
    • v.39 no.1
    • /
    • pp.35-42
    • /
    • 2016
  • Room-temperature operating CdZnTe(CZT) material is an innovative radiation detector which could reduce the patient dose to one-tenth level of conventional CT (Computed Tomography) and mammography system. The pixel and pixel pitch in the imaging device determine the conversion efficiency of incident X-or gamma-ray and the cross-talk of signal, that is, image quality of detector system. The weighting potential is the virtual potential determined by the position and geometry of electrode. The weighting potential obtained by computer-based simulation in solving Poisson equation with proper boundaries condition. The pixel was optimized by considering the CIE (charge induced efficiency) and the signal cross-talk in CT detector system. The pixel pitch was 1-mm and the detector thickness was 2-mm in the simulation. The optimized pixel size and inter-pixel distance for maximizing the CIE and minimizing the signal cross-talk is about $750{\mu}m$ and $125{\mu}m$, respectively.

Radiology Residents' Independent Diagnosis of Appendicitis Using 2-mSv Computed Tomography: A Secondary Analysis of a Large Pragmatic Randomized Trial

  • Jungheum Cho;Hae Young Kim;Seungjae Lee;Ji Hoon Park;Kyoung Ho Lee
    • Korean Journal of Radiology
    • /
    • v.24 no.6
    • /
    • pp.529-540
    • /
    • 2023
  • Objective: To compare the diagnostic performance and clinical outcomes of 2-mSv computed tomography (CT) and conventional-dose CT (CDCT), following radiology residents' interpretation of CT examinations for suspected appendicitis. Materials and Methods: Altogether, 3074 patients with suspected appendicitis aged 15-44 years (28 ± 9 years, 1672 females) from 20 hospitals were randomly assigned to the 2-mSv CT (n = 1535) or CDCT (n = 1539) groups in a pragmatic trial from December 2013 and August 2016. Overall, 107 radiology residents participated in the trial as readers in the form of daily practice after online training for 2-mSv CT. They made preliminary CT reports, which were later finalized by attending radiologists via addendum reports, for 640 and 657 patients in the 2-mSv CT and CDCT groups, respectively. We compared the diagnostic performance of the residents, discrepancies between preliminary and addendum reports, and clinical outcomes between the two groups. Results: Patient characteristics were similar between the 640 and 657 patients. Residents' diagnostic performance was not significantly different between the 2-mSv CT and CDCT groups, with a sensitivity of 96.0% and 97.1%, respectively (difference [95% confidence interval {CI}], -1.1% [-4.9%, 2.6%]; P = 0.69) and specificity of 93.2% and 93.1%, respectively (0.1% [-3.6%, 3.7%]; P > 0.99). The 2-mSv CT and CDCT groups did not significantly differ in discrepancies between the preliminary and addendum reports regarding the presence of appendicitis (3.3% vs. 5.2%; -1.9% [-4.2%, 0.4%]; P = 0.12) and alternative diagnosis (5.5% vs. 6.4%; -0.9% [-3.6%, 1.8%]; P = 0.56). The rates of perforated appendicitis (12.0% vs. 12.6%; -0.6% [-4.3%, 3.1%]; P = 0.81) and negative appendectomies (1.9% vs. 1.1%; 0.8% [-0.7%, 2.3%]; P = 0.33) were not significantly different between the two groups. Conclusion: Diagnostic performance and clinical outcomes were not significantly different between the 2-mSv CT and CDCT groups following radiology residents' CT readings for suspected appendicitis.

REPORT OF EXPERIENCE WITH KIMURA'S DISEASE (기무라씨 질환, 5 예 보고)

  • Seel David J.;Park Yoon-Kyu;Lee Kwang-Min
    • Korean Journal of Head & Neck Oncology
    • /
    • v.5 no.1
    • /
    • pp.39-46
    • /
    • 1989
  • Kimura's Disease is a chronic inflammatory and proliferative condition producing subcutaneous masses especially in the head and neck area. This report of our experience with 5 patients with this disease is the first in the Korean surgical literature. Kimura's Disease is thought to be part of the larger spectrum of the entity known as angiolymphoid hyperplasia with eosinophilia (ALHE). It is characterized pathologically by hyperplastic lymphoid follicles, eosinophilic infiltration, and vase 비 ar proliferation. It produces masses which are most common in the area of the parotid, submandibular gland and upper neck. These masses occupy the subcutaneous tissues but also extend into salivary tissue and into upper neck nodes. One of our patients had masses in the groin. The tumors are extremely vascular due to the presence of new proliferative vessels and sinusoids. The average age of our 5 patients was 35, but all but one case were younger than 38 years of age. The male: female ratio was 3 : 2, and the average duration of symptoms was 5,2years. All patients had peripheral blood eosinophilia. All had multiple masses, sometimes symmetrical. The management was surgery alone in one case, surgery and steroids in one case, surgery and radiotherapy in two cases, and all three modalities in one case. The relationship of this entity to ALHE and our experience in the management of this disease are presented. A clinicopathological discrepancy alerted us to the existence of Kimura's Disease. A nineteen-year old male presented with subcutaneous masses over both mastoid areas present for 3 years (Case III). When biopsy on each side was reported as 'eosinophilic granuloma' we submitted the slides to an internationally expert pathologist. Symmetrically occurring tumors in the peri-parotid subcutaneous areas did not fit any category of neoplasm or granuloma known to us. The diagnosis, made by Dr. Gist Fan at the Ochsner Clinic, was Kimura's Disease. We found two additional cases in a review of soft tissue eosinophilic granuloma previously reported at Presbyterian Medical Center, and since then have diagnosed two new cases. These five cases constitute the basis for this, the largest series to be reported in Korea. These vascular, tumor-like lesions of the skin, subcutaneous areas and subjacent structures of the head and neck have been a variety of names, such as angiolymphoid hyperplasia with eosinophilia, eosinophilic hyperplastic lymphogranuloma, angioblastic lymphoid hyperplasia with eosinophilia, histioid hemangioma, and epithelioid hemangioma. The history of this disease spectrum dates back to 1937 when Kimm and Szeto (1) reported 7 cases of 'eosinophilic hyperplastic lymphogranuloma' in the Proceedings of the Chinese Medical Journal. In 1948 Kimura and his associates(2) reported additional cases in Japan under the title 'On the unusual granulation combined with hyperplastic changes of lymphatic tissue.' From then until 1966 several hundred cases were reported in China and Japan. The first report from the West was by Wells and Whimster(3) in the British Journal of Dermatology, in 1969. These authors coined the term, angiolymphoid hyperplasia with eosinophilia (ALHE). Since that time a debate has ensued as to whether Kimura's Disease and ALHE are distinct entities, or whether Kimura's is part of the larger spectrum of ALHE, perhaps a later or advanced phase. From the clinical perspective, surgeons should be aware of the diagnosis of Kimura's Disease not only as part of the differential diagnosis of head and neck tumors but also because these lesions are indolent, and generally require conservative surgical removal as part of the management program. CASE I. A 37-year-old female company employee presented in August 1982 with submental swelling of 12 years' duration and with inguinal swelling of 7 years' duration. The submental mass measured 5x5cm. and the inguinal mass was 8x4cm. in size. Peripheral eosinophilia varying from 14% to 40% was found. On August 20, 1982, the submental mass was removed and a superficial groin dissection was done. In May 1983 an intraoral lesion of the palate was removed. The patient is free of disease. CASE II. A 23-year-old unemployed man visited this hospital for the first time in July, 1984, with swelling of the right cheek present for 6 years. The mass was soft and ill-defined but measured 10x20cm. and extended from the submandibular upper neck to the zygomatic arch, and from the mastoid to the cheek, over the parotid gland. Eosinophilia varying from 27% to 29% was noted in the peripheral blood. On March 21, 1986, the lesion was resected. The procedure comprised an extended superficial parotidectomy from the temporalis fascia to the upper neck. Post-operatively radiotherapy 3000 rad tissue dose was administered using the 6 MeV linear accelerator. The patient remains free of disease. CASE III. A 19-year-old student came to the clinic with masses over both mastoid areas, present 3 years. On the right there were two adjacent lesions, one over the mastoid, the other in the upper jugular level of the neck. On the left it was a single mass over the mastoid. Eosinophilia varied from 13 to 32% in the peripheral blood, and 11.6% in the bone marrow. Incisional biopsy revealed 'eosinophilic granuloma' and a trial of predisolone was employed. The mass increased in size so a small dose of radiation (600 rads) was used, with substantial regression,. The lesion on the left was excised and follwed by 1000 rads radiotherapy. Finally recurrent tumor on the right side was removed on November 5, 1985. The patient remains free of disease. CASE N. A 29-year-old local merchant had had swelling of both upper necks since childhood. At the time of his first visit on March 17, 1986, the right submandibular mass measured 5x3.5cm. and the ,right upper neck and parotid tail mass measured 2.5cm. On the left there were masses in the upper neck, the largest of which measured 2.5cm, and of the parotid tail, 2.0cm. in size.(See Fig. 1) Peripheral eosinophilia of 39% was recorded. Left side partial parotidectomy and resection of the upper neck and subdigstric mases was done on May 2, 1986. The mass involving the right parotid tail and upper neck nodes was removed on Angust 7,1986. Postoperatively the patient was placed on prednisolone 30 mg. per day. No definite masses are palpable. CASE V. A 66-year-old housewife informed us, at the time of her first visit in May, 1986, that she had had multiple neck masses since 10 years ago. On the right side there was a 2.5cm. subcutaneous mass of the upper neck, over the upper jugular chain. On the left there was a 9x4.5cm. mass involving the entire parotid, the post-auricular area and the upper neck. A third mass presented in the submental area and measured 3.5cm. (See Fig. 2) Eosinophilia of 51% was noted in the peripheral blood. partial excision of the left upper neck lesion and complete excision of the submental mass were performed on june 6, 1986. post-operatively she was placed on 20 mg. of prednisolone daily, but when the mass re-grew after two months she was referred to Radiation Therapy for a 2500 rad course of treatment. A barely palpable thickening remains.

  • PDF

A Study of Content Analysis on ICU(Intensive Care Unit) Nurses' Knowledge of Basic Nursing Sciences (중환자실 간호사의 기초간호과학 지식의 필요성 분석)

  • Byeon, Young-Soon;Choe, Myoung-Ae;Kim, Hee-Seung;Park, Mi-Jung;Seo, Wha-Sook;Lee, Kyung-Sook;Choi, S-Mi;Hong, Hae-Sook
    • Journal of Korean Biological Nursing Science
    • /
    • v.4 no.1
    • /
    • pp.41-49
    • /
    • 2002
  • The purpose of this study was to identify the knowledge contents of basic nursing sciences needed by nurses in the practices of the intensive care unit(ICU). To attain the goal of this study, the nurses working at 10 hospitals in the areas of Seoul and Kangwon Province were randomly selected. They were primarily interviewed, and the open question was secondarily put to them through the questionnaire. In the process of the 1st interview, the interviewees were asked of the question, "What is the knowledge of basic sciences such as anatomy, pathology, physiology. microbiology, pharmacology and the like thought to be lacking when you communicate with doctors in the ICU and when you carry out your nursing practices in it?" The contents of the interview were tape-recorded. The period of data collection ranged from May 1, 2001 to Sept 30. The interviews were conducted with total of 20 nurses. The open-end questionnaire was secondarily mailed to nurses. 113 questionnaires were returned. 100 questionnaires except 13 ones thought to be poorly completed in content were used for data analysis. Three coders classified data obtained from the interview and the questionnaire research into 5 detailed items relating to such as anatomical physiology, pathology, pharmacology. microbiology and basics of nursing. The three coders had experiences in nursing education of 18 years, 8 years and 6 years, respectively, and of them one coder was professor in basic nursing sciences. Data were statistically treated using frequency analysis and percentage by the SAS program. As a result, the following findings were obtained : It was found that the contents that ICU nurses responded were most needed in the field of Human structure and function were water and electrolytic balance(38%), blood and circulatory system(20%), changer in the patient's skin(12%), the arrangement of the human body(10%) and the endocrine system(10%), nervous system(6%), and assessment of the state of the patient's consciousness(4%). It was found that the contents that ICU nurses responded were most needed in the field of pathology were found to be the process of the progress of the disease(32%), symptoms of the disease(27%), prognosis of the disease(22%), followed by the injury-healing process, clinical pathological examination, and examination by radiation. It was found that the contents that nurses responded were most needed in the field of pharmacology were the effect of drug(25%), the side effect of drug(22%), the relationship between diseases and drug(20%), the relationship between disease-causing bacteria and drug(20%) and chemotherapy(2%). It was found that the contents that ICU nurses responded were most needed in the field of microbiology were the relationship between diseases and disease-causing bacteria(45%), Kinds and characteristics of disease-causing bacteria(18%), infection control(16%), application of the aseptic technique(12%), isolation(9%) and the like. It was found that the basic knowledge that ICU nurses responded were needed were the identification of the patient's current state(36%), understanding of the therapeutic process(22%), the operating principle of medical equipment and instrument(20%), medical terminology(9%), equipment and instrument management(7%), calculation of the dose of injection(2%) and the like.

  • PDF

Postoperstive Chemoradiotherapy in Locally Advanced Rectal Cancer (국소 진행된 직장암에서 수술 후 화학방사선요법)

  • Chai, Gyu-Young;Kang, Ki-Mun;Choi, Sang-Gyeong
    • Radiation Oncology Journal
    • /
    • v.20 no.3
    • /
    • pp.221-227
    • /
    • 2002
  • Purpose : To evaluate the role of postoperative chemoradiotherapy in locally advanced rectal cancer, we retrospectively analyzed the treatment results of patients treated by curative surgical resection and postoperative chemoradiotherapy. Materials and Methods : From April 1989 through December 1998, 119 patients were treated with curative surgery and postoperative chemoradiotherapy for rectal carcinoma in Gyeongsang National University Hospital. Patient age ranged from 32 to 73 years, with a median age of 56 years. Low anterior resection was peformed in 59 patients, and abdominoperineal resection in 60. Forty-three patients were AJCC stage II and 76 were stage III. Radiation was delivered with 6 MV X rays using either AP-PA two fields, AP-PA both lateral four fields, or PA both lateral three fields. Total radiation dose ranged from 40 Gy to 56 Gy. In 73 patients, bolus infusions of 5-FU $(400\;mg/m^2)$ were given during the first and fourth weeks of radiotherapy. After completion of radiotherapy, an additional four to six cycles of 5-FU were given. Oral 5-FU (Furtulone) was given for nine months in 46 patients. Results : Forty $(33.7\%)$ of the 119 patients showed treatment failure. Local failure occurred in 16 $(13.5\%)$ patients, 1 $(2.3\%)$ of 43 stage II patients and 15 $(19.7\%)$ of 76 stage III patients. Distant failure occurred in 31 $(26.1\%)$ patients, among whom 5 $(11.6\%)$ were stage II and 26 $(34.2\%)$ were stage III. Five-year actuarial survival was $56.2\%$ overall, $71.1\%$ in stage II patients and $49.1\%$ in stage III patients (p=0.0008). Five-year disease free survival was $53.3\%$ overall, $68.1\%$ in stage II and $45.8\%$ in stage III (p=0.0006). Multivariate analysis showed that T stage and N stage were significant prognostic factors for five year survival, and that T stage, N stage, and preoperative CEA value were significant prognostic factors for five year disease free survival. Bowel complication occurred in 22 patients, and was treated surgically in 15 $(12.6\%)$, and conservatively in 7 $(5.9\%)$. Conclusion : Postoperative chemoradiotherapy was confirmed to be an effective modality for local control of rectal cancer, but the distant failure rate remained high. More effective modalities should be investigated to lower the distant failure rate.

Comparative Analysis of Absorption Doses between Exposed and Unexposed Area on Major Organs During CT Scan (전산화 단층촬영시 주선속내 외의 주요장기 흡수선량 비교분석)

  • 사정호;서태석;최보영;정규회
    • Progress in Medical Physics
    • /
    • v.11 no.1
    • /
    • pp.59-71
    • /
    • 2000
  • It is possible to obtain a fast CT scan during breath holding with spiral technique. But the risk of radiation is increased due to detailed and repeated scans. However, the limitation of X-ray doses is not fully specified on CT, yet. Therefore, the purpose of the present study is to define the limitation of X-ray doses on CT The CT unit was somatom plus 4. Alderson Rando phantom, Solenoid water phantom, TLD, and reader were used. For determining adequate position and size of organs, the measurement of distance(${\pm}$2mm) from the midline of vertebral body was performed in 40 women(20~40 years). On the brain scan for 8:8(8mm slice thickness, 8mm/sec movement velocity of the table) and 10:10(10mm slice thickness, 10mm/sec movement velocity of the table) methods, the absorption doses of exposed area of the 10:10 were slightly higher than those of 8:8. The doses of unexposed uterus were negligible on the brain scan for both 8:8 and 10:10. On the chest scan for 8:8, 8:10(8mm slice thickness, 10mm/sec movement velocity of the table), 10:10, 10:12(10mm slice thickness, 12mm/sec movement velocity of the table) and 10:15(10mm slice thickness, 15mm/sec movement velocity of the table) methods, 8:8 method of the absorption doses of exposure area was the most highest and 10:15 method was the most lowest. The absorption doses of 8:10 method was relatively lower than those of the other methods. In conclusion, the 8:10 method is the most suitable to give a low radiation burden to patient without distorting image quality.

  • PDF

The Actual State and the Utilization for Dental Radiography in Korea (국내 치과방사선의 현황 및 이용 실태)

  • Shin, Gwi-Soon;Kim, You-Hyun;Lee, Bo-Ram;Kim, Se-Young;Lee, Gui-Won;Park, Chang-Seo;Park, Hyok;Chang, Kye-Yong
    • Journal of radiological science and technology
    • /
    • v.33 no.2
    • /
    • pp.109-120
    • /
    • 2010
  • The purpose of this study was first to analyze the utilization of dental examination through questionnaire to develop a diagnostic reference level of patient doses for dental radiography in korea. 77 dental institutions were classified into three groups: A group for the dental hospitals of the college of dentistry (11 institutions), B group for dental hospitals (30 institutions) and C group for dental clinics (36 institutions). The results were as follows : The mean numbers of unit chairs and medical staffs were 140.2, 15.3 and 5.8 sets, 112.6, 7.3 and 1.7 dentists, 3.1, 0.5 and no one radiologic technologists, and 19.7, 12.5 and 3.3 dental hygienists in A, B and C groups, respectively. The mean numbers of dental X-ray equipments were 14.64, 3.21 and 2.19 in A, B and C groups, respectively. Intraoral dental X-ray unit was used the most, the following equipments were panoramic, cephalometric, and cone-beam CT units. The most used X-ray imaging system was also digital system (above 50%) in all three groups. Insight dental film (Kodak, USA) having high sensitivity was routinely used for periapical radiography. The automatic processor was not used in many dental institutions, but the film-holding device was used in many dental institutions. The utilization rates of PACS in A, B and C groups were 90.9%, 83.3% and 16.7% respectively, and the PACS software program was used the most PiView STAR (Infinitt, Korea). The annual mean number of radiographic cases in one dental institution in 2008 for A group was 6.8 times and 21.2 times more than those for B and C groups, and periapical and panoramic radiographs were taken mostly. Tube voltage (kVp) and tube current (mA) for periapical radiography were similar in all three groups, but exposure time in C group was 12.0 times and 3.5 times longer than those in B and C groups. The amount of radiation exposure in C group, in which dental hygienists take dental radiographs, was more than those in other groups. The exposure parameters for panoramic radiography were similar in all three groups. In conclusion, the exposure parameters in dental radiography should be determined with reference level, not past experiences. Use of automatic processor and film-holding devices reduces the radiation exposure in film system. The quality assurance of dental equipments are necessary for the reduction of the patient dose and the improvement of X-ray image quality.

The Influence Evaluation of $^{201}Tl$ Myocardial Perfusion SPECT Image According to the Elapsed Time Difference after the Whole Body Bone Scan (전신 뼈 스캔 후 경과 시간 차이에 따른 $^{201}Tl$ 심근관류 SPECT 영상의 영향 평가)

  • Kim, Dong-Seok;Yoo, Hee-Jae;Ryu, Jae-Kwang;Yoo, Jae-Sook
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.14 no.1
    • /
    • pp.67-72
    • /
    • 2010
  • Purpose: In Asan Medical Center we perform myocardial perfusion SPECT to evaluate cardiac event risk level for non-cardiac surgery patients. In case of patients with cancer, we check tumor metastasis using whole body bone scan and whole body PET scan and then perform myocardial perfusion SPECT to reduce unnecessary exam. In case of short term in patients, we perform $^{201}Tl$ myocardial perfusion SPECT after whole body bone scan a minimum 16 hours in order to reduce hospitalization period but it is still the actual condition in which the evaluation about the affect of the crosstalk contamination due to the each other dissimilar isotope administration doesn't properly realize. So in our experiments, we try to evaluate crosstalk contamination influence on $^{201}Tl$ myocardial perfusion SPECT using anthropomorphic torso phantom and patient's data. Materials and Methods: From 2009 August to September, we analyzed 87 patients with $^{201}Tl$ myocardial perfusion SPECT. According to $^{201}Tl$ myocardial perfusion SPECT yesterday whole body bone scan possibility of carrying out, a patient was classified. The image data are obtained by using the dual energy window in $^{201}Tl$ myocardial perfusion SPECT. We analyzed $^{201}Tl$ and $^{99m}Tc$ counts ratio in each patients groups obtained image data. We utilized anthropomorphic torso phantom in our experiment and administrated $^{201}Tl$ 14.8 MBq (0.4 mCi) at myocardium and $^{99m}Tc$ 44.4 MBq (1.2 mCi) at extracardiac region. We obtained image by $^{201}Tl$ myocardial perfusion SPECT without gate method application and analyzed spatial resolution using Xeleris ver 2.0551. Results: In case of $^{201}Tl$ window and the counts rate comparison result yesterday whole body bone scan of being counted in $^{99m}Tc$ window, the difference in which a rate to 24 hours exponential-functionally notes in 1:0.114 with Ventri (GE Healthcare, Wisconsin, USA), 1:0.249 after the bone tracer injection in 12 hours in 1:0.411 with 1:0.79 with Infinia (GE healthcare, Wisconsin, USA) according to a reduction a time-out was shown (Ventri p=0.001, Infinia p=0.001). Moreover, the rate of the case in which it doesn't perform the whole body bone scan showed up as the average 1:$0.067{\pm}0.6$ of Ventri, and 1:$0.063{\pm}0.7$ of Infinia. According to the phantom after experiment spatial resolution measurement result, and an addition or no and time-out of $^{99m}Tc$ administrated, it doesn't note any change of FWHM (p=0.134). Conclusion: Through the experiments using anthropomorphic torso phantom and patients data, we found that $^{201}Tl$ myocardium perfusion SPECT image later carried out after the bone tracer injection with 16 hours this confirmed that it doesn't receive notable influence in spatial resolution by $^{99m}Tc$. But this investigation is only aimed to image quality, so it needs more investigation in patient's radiation dose and exam accuracy and precision. The exact guideline presentation about the exam interval should be made of the validation test which is exact and in which it is standardized about the affect of the crosstalk contamination according to the isotope use in which it is different later on.

  • PDF

Once vs. Twice Daily Thoracic Irradiation in Limited Stage Small Cell Lung Cancer (국한성 병기 소세포폐암의 방사선치료시 분할 조사방식에 따른 치료성적)

  • Kim, Jun-Sang;Kim, Jae-Sung;Kim, Ju-Ock;Kim, Sun-Young;Cho, Moon-June
    • Radiation Oncology Journal
    • /
    • v.16 no.3
    • /
    • pp.291-301
    • /
    • 1998
  • Purpose : A retrospective study was conducted comparing single daily fraction (SDF) thoracic radiotherapy (TRT) with twice daily (BID) TRT to determine the potential benefit of BID TRT in limited-stage small cell lung cancer (SCLC). Endpoints of the study were response. survival, pattern of failure, and acute toxicity. Materials and Methods : Between November 1989 to December 1996, 78 patients with histologically proven limited-stage SCLC were treated at the Department of Therapeutic Radiology, Chungnam National University Hospital. Of these, 9 were irradiated for palliative intent, and 1 had recurrent disease. Remaining 68 patients were enrolled in this study. There were 26 patients with a median age of 58 years, and 22 (85$\%$) ECOG performance score of less than 1 in SDF TRT. There were 42 patients with a median age of 57 years, and 36 (86$\%$) ECOG performance score of less than 1 in BID TRT By radiation fractionation regimen, there were 26 in SDF TRT and 42 in BID TRT. SDF TRT consisted of 180 cGy, 5 days a week. BID TRT consisted of 150 cGy BID, 5 days a week in 13 of 42 and 120 cGy BID, in 29 of 42. And the twice daily fractions were separated by at least 4 hours. Total radiotherapy doses were between 5040 and 6940 cGy (median, 5040 cGy) in SDF TRT and was between 4320 and 5100 cGy (median, 4560 cGy) in BID TRT. Prophylactic cranial irradiation (PCI) was recommended for patients who achieved a CR. The recommended PCI dose was 2500 cGy/10 fractions. Chemotherapy consisted of CAV (cytoxan 1000 mg/$m^2$, adriamycin 40 mg/$m^2$, vincristine 1 mg/$m^2$) alternating with VPP (cisplatin 60 mg/$m^2$, etoposide 100 mg/$m^2$) every 3 weeks in 25 (96$\%$) of SDF TRT and in 40 (95$\%$) of BID TRT. Median cycle of chemotherapy was six in both group. Timing for chemotherapy was sequential in 23 of SDF TRT and in 3 BID TRT, and concurrent in 3 of SDF TRT and in 39 of BID TRT Follow-up ranged from 2 to 99 months (median, 14 months) in both groups. Results : Of the 26 SDF TRT, 9 (35$\%$) achieved a complete response (CR) and 14 (54$\%$) experienced a partial response (PR). Of the 42 BID TRT, 18 (43$\%$) achieved a CR and 23 (55$\%$) experienced a PR. There was no significant response difference between the two arms (p=0.119). Overall median and 2-year survival were 15 months and 26.8$\%$, respectively. The 2-year survivals were 26.9$\%$ and 28$\%$ in both arm, respectively (p=0.51). The 2-rear survivals were 35$\%$ in CR and 24.2$\%$ in PR, respectively. The grade 2 to 3 esophageal toxicities and grade 2 to 4 neutropenias were more common in BID TRT (p=0.028 0.003). There was no difference in locoregional and distant metastasis between the two arms (p=0 125 and 0.335, respectively). The most common site of distant metastasis was the brain. Conclusion : The median survival and 2-year survival were 17 months and 20.9$\%$ in SDF TRT with sequential chemotherapy, and 15 months and 28$\%$ in BID TRT with concurrent chemotherapy, respectively. We did not observe a substantial improvement of long-term survival in the BID TRT with concurrent chemotherapy compared with standard schedules of SDF TRT with sequential chemotherapy. The grade 2 to 3 esophageal toxicities and glade 2 to 4 neutropenias were more common in BID TRT with concurrent chemotherapy. Although the acute toxicities were more common in BID TRT with concurrent chemotherapy than SDF TRT with sequential chemotherapy, a concurrent chemotherapy and twice daily TRT was feasible. However further patient accrual and long-term follow up are needed to determine the potential benefits of BID TRT in limited-stage SCLC.

  • PDF

Utility of Wide Beam Reconstruction in Whole Body Bone Scan (전신 뼈 검사에서 Wide Beam Reconstruction 기법의 유용성)

  • Kim, Jung-Yul;Kang, Chung-Koo;Park, Min-Soo;Park, Hoon-Hee;Lim, Han-Sang;Kim, Jae-Sam;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.14 no.1
    • /
    • pp.83-89
    • /
    • 2010
  • Purpose: The Wide Beam Reconstruction (WBR) algorithms that UltraSPECT, Ltd. (U.S) has provides solutions which improved image resolution by eliminating the effect of the line spread function by collimator and suppression of the noise. It controls the resolution and noise level automatically and yields unsurpassed image quality. The aim of this study is WBR of whole body bone scan in usefulness of clinical application. Materials and Methods: The standard line source and single photon emission computed tomography (SPECT) reconstructed spatial resolution measurements were performed on an INFINA (GE, Milwaukee, WI) gamma camera, equipped with low energy high resolution (LEHR) collimators. The total counts of line source measurements with 200 kcps and 300 kcps. The SPECT phantoms analyzed spatial resolution by the changing matrix size. Also a clinical evaluation study was performed with forty three patients, referred for bone scans. First group altered scan speed with 20 and 30 cm/min and dosage of 740 MBq (20 mCi) of $^{99m}Tc$-HDP administered but second group altered dosage of $^{99m}Tc$-HDP with 740 and 1,110 MBq (20 mCi and 30 mCi) in same scan speed. The acquired data was reconstructed using the typical clinical protocol in use and the WBR protocol. The patient's information was removed and a blind reading was done on each reconstruction method. For each reading, a questionnaire was completed in which the reader was asked to evaluate, on a scale of 1-5 point. Results: The result of planar WBR data improved resolution more than 10%. The Full-Width at Half-Maximum (FWHM) of WBR data improved about 16% (Standard: 8.45, WBR: 7.09). SPECT WBR data improved resolution more than about 50% and evaluate FWHM of WBR data (Standard: 3.52, WBR: 1.65). A clinical evaluation study, there was no statistically significant difference between the two method, which includes improvement of the bone to soft tissue ratio and the image resolution (first group p=0.07, second group p=0.458). Conclusion: The WBR method allows to shorten the acquisition time of bone scans while simultaneously providing improved image quality and to reduce the dosage of radiopharmaceuticals reducing radiation dose. Therefore, the WBR method can be applied to a wide range of clinical applications to provide clinical values as well as image quality.

  • PDF