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@#Positron emission tomography/computed tomography (PET/CT) scanner is an irreplaceable instrument in clinical diagnosis. The exposure dose that a patient receives is the sum of the doses caused by PET and CT examination. This study discussed the exposure dose level that a patient received during PET/CT examination according to the research data. Like other radiological diagnostic methods, PET/CT examination brings benefits outweighing its radiation risk. It is not advisable to exaggerate or ignore the exposure dose. The patient’s exposure dose caused by PET/CT examination should be controlled as much as possible under the premise of meeting clinical needs.
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@#<b>Objective</b> To investigate and analyze the levels of γ dose rate and radon concentration at all sites in a large open-pit coal mine with radioactivity that had been mined for many years in Xinjiang, China, and to estimate the effective dose exposed to the personnel. <b>Methods</b> A portable γ dose-rate instrument FH40G was used for fixed-point monitoring of the mining area, and a continuous radon detector was used for 24 h continuous monitoring of radon concentration level in the site. The personnel exposure dose was estimated according to the measured γ dose rate and radon concentration. <b>Results</b> In this open-pit coal mine, the range of γ dose rate was 51.4-435.8 nGy/h; the mean 24 h radon concentration was 15-25 Bq/m<sup>3</sup>; the range of annual effective dose to the personnel was 0.29-1.29 mSv/a. <b>Conclusion</b> According to the results of the survey, radon concentration levels at all sites are low, and no remedial action is required. The personnel exposure dose at most of the sites is far below the standard requirements, and some protective measures need to be taken in some areas of the dump.
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Objective To investigate the epidemiological characteristics of occupational noise induced deafness (ONID) in Nantong area and analyze the risk factors. Methods A total of 421 workers in hydropower industry who underwent physical examination in the outpatient clinic of Nantong Center for Disease Control and Prevention from January 2017 to December 2021 were selected as the research subjects.168 workers without ONID were divided into control group, and 253 workers diagnosed with ONID were divided into ONID group. The expression levels of serum cortisol, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the two groups were compared and analyzed. Results There were more males than females in both groups (P<0.05). With the increase of working age, the detection rate of ONID also increased significantly (P<0.05). The hearing thresholds of left and right ears in workers of different workplaces in the ONID group were higher than those in the control group (P<0.05), and the hearing thresholds of workers in water wheel room and water machine operation duty room were higher (P<0.05). The expression levels of cortisol, IL-6 and TNF-α in the serum of ONID patients were significantly higher than those in the control group. Multivariate analysis showed that workplace, serum cortisol, IL-6 and TNF-α were the main influencing factors for ONID. Conclusion Workplace, serum cortisol, IL-6 and TNF-α are all risk factors for ONID. Appropriate measures should be taken to strengthen the prevention and treatment of noise-induced hearing loss according to the influencing factors.
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Objective To determine the radiation dose of sensitive organs under different protective methods in lung CT scanning environment, and to explore the best protective scheme of corresponding organs. Methods Annealed thermoluminescence dose elements were placed in the stomach, liver, colon, and thyroid gland of a simulated human body model. The dose effect experiment of protective methods included non-protective group, half lead apron group, and full lead apron group. The dose effect experiment of protective thickness included 0.50 mmpb full lead apron group and 0.35 mmpb full lead apron group. The same exposure conditions of lung CT scan were used in the above experiments. Results Compared with the non-protective group, the exposure dose of the stomach, liver, colon, and thyroid gland increased significantly in the half lead apron group (P < 0.05), and the exposure dose of the thyroid gland and colon decreased significantly in the full lead apron group (P < 0.05). There were no significant differences in the exposure dose of the liver, stomach, and colon in the simulated human body model between the 0.35 mmpb full lead apron group and the 0.50 mmpb full lead apron group. Conclusion For lung CT scan, the protective measure of lead apron may not reduce the exposure dose of subjects. The protective thickness of lead apron does not necessarily have a substantial influence on the exposure dose of human body.
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Objective@#To explore the clinical value of 3D-DSA technology in the diagnosis and treatment guidance of hepatic artery chemoembolization.@*Methods@#Liver cancer patients in the treatment groups were collected to receive 3D-DSA imaging guidance at the Affiliated Hospital of Xuzhou Medical University between March and May 2017. In addition, routine 2D-DSA imaging was selected for treatment-received group. Intra-operative blood vessels and tumor-like lesions were observed. The total exposure dose (CAK, unit mGy), cumulative irradiation intensity per unit area (DAP, unit mGy.cm2) and dosage of contrast agent (ml) were calculated separately for two groups of patients. The same senior physicians and technicians operated both groups of patients. Comparisons of measurement were analyzed by t-test and chi-square test was used for count data.@*Results@#Data of twenty patients were collected from the two groups. Tumor location, target vessels structure and shape of development were clear in all patients in the treatment group. The control group had 17 cases of tumor development and the target vascular structure was clear in 16 cases. CAK mean treatment group was lower than control group (554.11 + 38.87) mGy and (644.53 + 26.70) mGy, and DAP mean treatment group was lower than the control group (125.25 + 7.54) mGy·cm2 and (143.49 + 6.18) mGy·cm2. The two groups were compared (P value < 0.05), and the differences were statistically significant. The mean dose of contrast agent in the two groups were lower than control group (64.42 + 3.92) ml, (70.79 + 4.47) ml, and the differences between the two groups were statistically significant (P < 0.05).@*Conclusion@#3D-DSA imaging technology can provide effective diagnosis and guidance in the treatment of hepatic artery chemoembolization. It can effectively reduce the radiation exposure dose and radiation intensity, and it is of high clinical value for interventional embolization of liver cancer.
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Objective To evaluate the influence of indoor air filtration by air purifier on the behavior of indoor radon progeny and estimate its effects on indoor radon exposure to residents.Methods The concentrations of indoor radon progeny with and without the air filtration were calculated by the theoretical model developed in this study.Based on the dose conversion factors of attached and unattached radon progeny,the mitigation effects of indoor radon exposure due to the air filtration were estimated.Verification experiments were conducted in an airtight room.Results With the air filtration rate increased,the removal efficiency of indoor radon progeny would appear more obvious.For an airtight room with its initial aerosol concentration of 10 000 cm-3,the concentration of total radon progeny would decrease by more than 90％ when the air filtration rate exceeded 10 h-1.But the concentrations of indoor unattached radon progeny would increase by using the air purifier in different extents.The variations of radon progeny concentrations and the decrease of internal doses were closely related to the filtration rate of air purifier.With the air filtration rates increased,the mitigation effects would be better and faster.The internal dose would reduce by more than 70％ when the filtration rate exceeded 5 h-1.Conclusions Although the indoor concentration of unattached radon progeny will increase by using the air purifier,it is still effective in reducing the exposure dose to residents due to the inhalation of radon progeny.
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Objective To investigate the association between the level of advanced oxidation protein products (AOPP) in serum and the dialysate glucose exposure dose in patients undergoing non-diabetic maintenance peritoneal dialysis (PD). Methods In this cross-sectional study, the levels of serum AOPP were measured in 192 non-diabetic PD patients. Based on the exposure dose of dialysate glucose , PD patients were assigned into the high-dose exposure and low-dose exposure groups. Serum C-reactive protein levels were also measured and the rates of cardio-vascular disease (CVD) were recorded in both groups. Results The levels of serum AOPP were higher in the high-dose exposure group, as compared with the low-dose exposure group [(78.7 ± 15.6) mmol/L vs. (71.7 ± 14.8) mmol/L, P = 0.003]. The serum C-reactive protein levels [4.6 (3.0-11.4) mg/L vs. 3.0 (2.2-5.3) mg/L, P < 0.001] and the rates of CVD (53.6% vs. 35.8%, P = 0.014) were also higher in the high-dose exposure group. After multivariate adjustment ,the level of serum AOPP was independently associated with dialysate glucose exposure dose (β = 0.157, P = 0.031) and duration of PD (β = 0.164, P =0.043). Conclusion The serum AOPP levels are associated with the dialysate glucose exposure doses in non-diabetic PD patients. Minimizing the glucose load might reduce the risk of developing CVD.
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Objective To study environmental safety reference standard values of commonly encountered pathogenic microorganisms, and provide the basis for environmental risk assessment of a high-level biosafety laboratory (BSL).Methods Using human exposure dose calculation methods as the basic principle in combination with microbial hazard evaluation methods , an infectious dose calculation model of human exposure to pathogenic microorganisms by breathing was proposed . Based on research on characteristics of commonly encountered pathogenic microorganisms at home and abroad , the environ-mental safety threshold reference standard and environmental risk protection zone for such microorganisms were obtained . Results An the environmental risk assessment standard calculation method for commonly encountered highly pathogenic microorganisms was proposed , and the minimum infectious dose and environmental safety threshold of seven commonly encountered pathogenic microorganisms were obtained , including SARS coronavirus , highly pathogenic avian influenza virus, Mycobacterium tuberculosis, Bacillus anthracis, Yersinia pestis,Francisella tularensis, and epidemic hemorrhagic fever virus.Conclusion The results can be used as a reference standard of infectious aerosols in a high-level BSL for environ-mental risk assessment , laboratory risk control and emergency management .
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Objectives: Radon (222Rn) is a noble gas found in the water of hot spring spas (“onsen”). In Japan, the Hot Springs Law and the Guideline of Analytical Methods of Mineral Springs (revised) classify springs containing 74 Bq/kg of radon as “hot springs” and those with levels exceeding 111 Bq/kg as “medical springs”, also called “radioactive springs”. According to the notification article (the Nature Conservation Bureau of the Ministry of the Environment in Japan), bathing in a radioactive springs may alleviate the effects of gout, arteriosclerosis, and hypertension as well as chronic conditions such as cholecystitis, gallstones, and skin and gynecological diseases. Drinking water from these springs may treat gout, chronic digestive disorders, chronic cholecystitis, gallstones, neuralgia, muscle pain, and arthralgia. To determine exposure doses from radioactive springs, it is important to establish an easy and accurate method of measuring radon concentration in water and humid air in bathing areas. Methods: This study measured the concentration of airborne radon using an activated charcoal detector (PICO-RAD: AccuStar Labs), desiccant (Drierite; 8 mesh of anhydrous calcium sulfate: W.A. Hammond Drierite Company, Ltd.), a liquid scintillation counter (LSC LB-5: Hitachi Aloka Medical, Ltd.), and 2,5-diphenyloxazole(DPO) + 1,4-bis (5-phenyl-2-oxazolyl) benzene(POPOP) toluene solution (Wako Pure Chemical Industries, Ltd.) were used as the liquid scintillator. Results and Conclusions: This study evaluated radon exposure doses due to radioactive spring at a spa in Komono town, Mie prefecture. After water was piped from hot spring storage tanks into bathtubs, only 5.3-18.0% of the radon remained in the water. Two days later, only 0.25% remained, likely due to radioactive decay and increased diffusion into the air from bathing and recirculating filters. Thus, we investigated radon levels in the humid bathroom air around the radioactive hot spring and determined the total radon exposure from spa water and air. The total exposure dose was calculated assuming a two-day stay, during which customers used the bath for some number of hours. Our findings confirm the safety and efficacy of the hot spring facility. This study was supported in part by a grant from the Daido Life Welfare Foundation.
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Objectives: Radon (222Rn) is a noble gas and a component of water in many hot spring spas. The Hot Springs Law and the Guideline of Analytical Methods of Mineral Springs (revised edition) of Japan classify springs containing 74 Bq/kg or more of radon as “hot springs” and those with radon levels exceeding 111 Bq/kg as “medical springs”, also called “radioactive springs”. Komono Town, one of the foremost spa and health resort destinations in Mie Prefecture, is the site of many radioactive springs. For the purpose of regional vitalization of this area through radioactive springs, it is necessary to confirm the safety and effectiveness of their use. To evaluate the exposure dose due to radioactive spring usage, it is important to measure radon concentration in air, especially in high-humidity air such as in bathing rooms. Methods: The concentration of radon in air was analyzed using an activated charcoal detector (PICO-RAD; AccuStar Labs) with a desiccant (Drierite; 8-mesh anhydrous calcium sulfate; W.A. Hammond Drierite Company, Ltd.) and a liquid scintillation counter (LSC LB-5; Hitachi Aloka Medical, Ltd.). A DPO (2,5-diphenyloxazole) + POPOP (1,4-bis- (5-phenyl-2-oxazolyl)-benzene) toluene solution (Wako Pure Chemical Industries, Ltd.) was used as a liquid scintillator. Activated charcoal detectors were set up in and around the radioactive spring facilities. Results and Discussion: In a radioactive spring facility, radon concentration in air in the bathing room and changing room were relatively high at about 50 Bq/m3. In the corridor on all floors and at the entrance, these values were approximately 10-30 Bq/m3, indicating that radon in hot spring water diffuses into the air and spreads within the facility. Outdoors, radon concentration was 12.5 Bq/m3 at a campsite near the discharge point of the radioactive spring. Exposure dose is calculated under the assumption of a two-day stay, during which the visitor will use the bath for several hours. The results obtained show that the exposure dose at the hot spring facility is lower than the exposure dose from daily environmental radiation or medical devices. These conclusions are considered sufficient to confirm the safety of the hot spring facility.
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<b>Objectives:</b> Radon (<sup>222</sup>Rn) is a noble gas and a component of water in many hot spring spas. The Hot Springs Law and the Guideline of Analytical Methods of Mineral Springs (revised edition) of Japan classify springs containing 74 Bq/kg or more of radon as “hot springs” and those with radon levels exceeding 111 Bq/kg as “medical springs”, also called “radioactive springs”. Komono Town, one of the foremost spa and health resort destinations in Mie Prefecture, is the site of many radioactive springs. For the purpose of regional vitalization of this area through radioactive springs, it is necessary to confirm the safety and effectiveness of their use. To evaluate the exposure dose due to radioactive spring usage, it is important to measure radon concentration in air, especially in high-humidity air such as in bathing rooms.<BR><b>Methods:</b> The concentration of radon in air was analyzed using an activated charcoal detector (PICO-RAD; AccuStar Labs) with a desiccant (Drierite; 8-mesh anhydrous calcium sulfate; W.A. Hammond Drierite Company, Ltd.) and a liquid scintillation counter (LSC LB-5; Hitachi Aloka Medical, Ltd.). A DPO (2,5-diphenyloxazole) + POPOP (1,4-bis- (5-phenyl-2-oxazolyl)-benzene) toluene solution (Wako Pure Chemical Industries, Ltd.) was used as a liquid scintillator. Activated charcoal detectors were set up in and around the radioactive spring facilities. <BR><b>Results and Discussion:</b> In a radioactive spring facility, radon concentration in air in the bathing room and changing room were relatively high at about 50 Bq/m<sup>3</sup>. In the corridor on all floors and at the entrance, these values were approximately 10-30 Bq/m<sup>3</sup>, indicating that radon in hot spring water diffuses into the air and spreads within the facility. Outdoors, radon concentration was 12.5 Bq/m<sup>3</sup> at a campsite near the discharge point of the radioactive spring.<BR> Exposure dose is calculated under the assumption of a two-day stay, during which the visitor will use the bath for several hours. The results obtained show that the exposure dose at the hot spring facility is lower than the exposure dose from daily environmental radiation or medical devices. These conclusions are considered sufficient to confirm the safety of the hot spring facility.
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<b>Objectives: </b>Radon (<sup>222</sup>Rn) is a noble gas found in the water of hot spring spas (“onsen”). In Japan, the Hot Springs Law and the Guideline of Analytical Methods of Mineral Springs (revised) classify springs containing 74 Bq/kg of radon as “hot springs” and those with levels exceeding 111 Bq/kg as “medical springs”, also called “radioactive springs”. According to the notification article (the Nature Conservation Bureau of the Ministry of the Environment in Japan), bathing in a radioactive springs may alleviate the effects of gout, arteriosclerosis, and hypertension as well as chronic conditions such as cholecystitis, gallstones, and skin and gynecological diseases. Drinking water from these springs may treat gout, chronic digestive disorders, chronic cholecystitis, gallstones, neuralgia, muscle pain, and arthralgia. To determine exposure doses from radioactive springs, it is important to establish an easy and accurate method of measuring radon concentration in water and humid air in bathing areas.<BR><b>Methods: </b>This study measured the concentration of airborne radon using an activated charcoal detector (PICO-RAD: AccuStar Labs), desiccant (Drierite; 8 mesh of anhydrous calcium sulfate: W.A. Hammond Drierite Company, Ltd.), a liquid scintillation counter (LSC LB-5: Hitachi Aloka Medical, Ltd.), and 2,5-diphenyloxazole(DPO) + 1,4-bis (5-phenyl-2-oxazolyl) benzene(POPOP) toluene solution (Wako Pure Chemical Industries, Ltd.) were used as the liquid scintillator.<BR><b>Results and Conclusions: </b>This study evaluated radon exposure doses due to radioactive spring at a spa in Komono town, Mie prefecture. After water was piped from hot spring storage tanks into bathtubs, only 5.3-18.0% of the radon remained in the water. Two days later, only 0.25% remained, likely due to radioactive decay and increased diffusion into the air from bathing and recirculating filters. Thus, we investigated radon levels in the humid bathroom air around the radioactive hot spring and determined the total radon exposure from spa water and air. The total exposure dose was calculated assuming a two-day stay, during which customers used the bath for some number of hours. Our findings confirm the safety and efficacy of the hot spring facility. This study was supported in part by a grant from the Daido Life Welfare Foundation.
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OBJECTIVES: In this study, radiotechnologists who work performing PET and PET/CT methodologies were analyzed in order to find the cause for the differences in radiation exposure as they applied to general characteristics, work characteristics, knowledge, and exposure recognition or conduct. METHODS: From April 15th, 2010 to May 14th, 2010, we conducted a retrospective analysis on 80 radiotechnologists using data garnered from their individual general characteristics, work characteristics, knowledge, and exposure recognition or conduct. Their average annual radiation exposure dosages were measured using a thermoluminescence dosimeter. A multiple regression analysis was performed as a statistical tool. RESULTS: Regarding the general PET and PET/CT characteristics, when the work experience was short, the exposure dose was higher. The factors of age, marriage, work experience in nuclear medicine, PET, PET/CT, and sex were found to have statistically significant effects. The knowledge, recognition, and conduct factors for the radiotechnologists were affected by unsecure radiation exposure at the moment of carrying, unsecure radiation exposure at the moment of injection, the application of protection at the moment of injection, and the use of auto distributor. It was found that, the use of an auto distributor, efforts in reducing the radiation exposure, unsecure exposure when with a patient, and the application of protective procedures at the moment of injection affected the overall factor of radiotechnologists radiation exposure dose. CONCLUSIONS: We believe that if radiotechnologists would reduce their radiation exposure by using auto distributors, make efforts to reduce the chance of exposure, and be conscious of radiation, they would be able to reduce the radiation exposure dose even during unavoidable circumstances.
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Humans , Lifting , Marriage , Nuclear Medicine , Retrospective StudiesABSTRACT
Objective To compare the difference of entrance dose between CR and amorphous silocon DR system in chest imaging, and to discuss their optimum exposure dose. Methods For CR and DR, different entrance dose was measured by dosimeter in chest phantom. The value of IQFinv was analyzed by CDRAD2. 0 software. Image quality difference between CR and DR was assessed by group t-test. The relationship between image quality and entrance dose was tested by using Pearson correlation analysis. The best IQFinv values in CR and DR system were achieved via ROC curve analysis, and the exposure dose was then calculated. Results There were direct correlation values between entrance dose and the value of IQFinv in CR and DR system, respectively( r =0. 893 ,0. 848 ,P < 0. 01 ) . The linear regression equation for DR was IQFinv =0. 0050 +3. 359, and for CR was IQFinv =0. 005D + I. 651 , where D was entrance dose. The difference of IQFinv value between CR and DR was significant(t = 5. 455 ,P < 0. 05). The best IQFinv value of the two groups from ROC analysis was 3.55. Conclusions With the entrance dose increased, the detection ability of contrast-detail was elevated in the two digital radiography systems. With equal entrance dose, the detection ability of DR in contrast-detail was superior to CR. With equal image quality, DR obviously decreased the radiation dose to the patients.
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Objective To improve the image intensifying X-TV system by replacing the light-conduct camera with CCD camera for future usage.Methods The low luminous and high sensitive CCD camera was used in the X-ray auto exposure dose control.Results Through the practical improvement,the CCD X-TV system met the clinical requirements.Conclusion It is an effective way to replace the old light-conduct camera with CCD camera,and it also helpful for the alternative solutions for X-TV.
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Computed Radiology(CR) has been used widely with the development of digital imaging technology.CR technique has shown many advantages over traditional radiography.However,the control to radioactive exposure dose is an indispensable issue during clinical practice.
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Objective To investigate the exposure level to vehicle exhaust pollution for population by different commuting modes in roadside environment in Wuhan. Methods Eight air monitoring sites were selected in the six main roads in urban area of Wuhan, Hubei province. The concentrations of NO2, CO, total hydro carbon (THC), PM10, benzene, toluene and xylenes (BTX) emitted from the vehicles were monitored and analyzed in winter and summer of 2007, respectively and combined with breathing rate and time spent of the population in traffic environments, exposure doses of different subpopulation were calculated as indicators in order to evaluate their exposure level to traffic exhaust. Results The PM10 was the primary pollutant on the roadside. Compared with the Ambient Air Quality Standard, the rate of exceeding standard limit for PM10 was 8% in summer and 100% in winter. As for on the roadside, the exposure level for adults was higher than that for the children (P
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To measure the levels of X ray radiation emitted from computer video display terminals Accumulative doses of X ray radiation emitted from the surface of terminal screen and radiation protcetive screen were measured by highly sensitive LiF(Mg,Cu,P) thermoluminescent dosimetry The average levels of X ray radiation emitted from the surface of terminal screen and radiation protective screen were 0 93 mR/d and 0 24 mR/d respectively [Conclusion]The low energy and low level X ray radiation emitted from the terminals didn′t exceed the related standards
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The environmental sources of radon, its properties, pathways of human exposure, mechanisms of tox-icity and adverse health effects are described. This paper presents a review of research progress on radon in the recent ten years, which includes pollution levels in indoor air, internal exposure dose of human beings, remedial measures for decreasing the hazards induced by radon and main technical methods to reduce radon concentration in indoor air. Some reference data suggests that with the economic development and the improvement of residential environment, the air conditioners and unqualified building materials or decoration materials being used more extensively in residences. As a result, indoor air radon pollution and its impact on health are becoming of wide concern.
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Objective To investigate the magnitude of dose equivalent of exposure dose in different organs of human being using high and low KV X-Ray photography in chest.Methods Dose equivalent of exposure in point of centricity,thyroid,mammary gland and pubic symphysis were detected using thermoluminescence determinator when photographed using different size of exposure field or high and low KV in chest.Results Using center measure point as reference point,dose equivalent in high KV reduced 82% in average to low KV in posterior-anterior position of chest,dose equivalent in high KV reduced 194% in average to low KV in lateral position of chest.All dose equivalent of exposure dose in sensitive organs in non-projection center in high KV photography lower than those in low KV photography.Conclusion When the KV is as high as possible and the exposure field is as small as possible,each dose equivalent of exposure dose of organs out of exposure field is decrease.Dose equivalent of exposure dose in mammary is the highest,those in thyroid is the secondary,and genitical gland area has the lowest dose.