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O câncer de cabeça e pescoço (CCP) refere-se ao grupo de tumores que atingem a laringe, cavidade nasal, nasofaringe, orofaringe, cavidade oral e glândulas salivares. A radioterapia no paciente com CCP representa uma terapia para manutenção do órgão, através da destruição das células neoplásicas malignas. O objetivo do presente estudo foi identificar estratégias radioterápicas aplicadas ao paciente com CCP e seus respectivos efeitos colaterais em cavidade oral, além de investigar as principais modalidades utilizadas nos sistemas de saúde do Brasil. Tratou-se de uma revisão narrativa da literatura com busca ativa das bases eletrônicas PUBMED, LILACS e SCIELO. Após todas as etapas de refinamento, um total de 58 artigos foram incluídos na presente revisão. A radioterapia possui papel de destaque no tratamento do CCP. No entanto, por não ser um método terapêutico com alta especificidade, resulta em efeitos adversos ao tratamento como mucosite oral, trismo e disfunção salivar, que findam por reduzir a qualidade de vida do paciente. Dentre as principais técnicas radioterapêuticas utilizadas no Brasil, a IMRT e VMAT caracterizam-se como as formas mais avançadas da terapia em 3D, proporcionando doses equivalentes para cada área da lesão tumoral, poupando áreas teciduais circunvizinhas que não necessitam de irradiação. Além da toxicidade reduzida, uma maior sobrevida pode ser observada em pacientes tratados com essas técnicas. Um dos maiores desafios atuais na radioterapia contra o CCP é a proteção de tecidos saudáveis. Nesse sentido, a IMRT e VMAT apresentam superioridade em relação às demais técnicas.
Head and neck cancer (CCP) refers to the group of tumors that affect the larynx, nasal cavity, nasopharynx, oropharynx, oral cavity and salivary glands. Radiotherapy in patients with CCP represents a therapy for organ maintenance, through the destruction of malignant neoplastic cells. The aim of this study was to identify radiotherapy strategies applied to patients with CCP and their respective side effects in the oral cavity, and to investigate the main modalities used in health systems in Brazil. It was a narrative review of the literature with active search of electronic databases PUBMED, LILACS and SCIELO. After all stages of refinement, a total of 58 articles were included in this review. Radiotherapy has a prominent role in the treatment of CCP. However, because it is not a therapeutic method with high specificity, it results in adverse effects to treatment such as oral mucositis, trismus and salivary dysfunction, which end up reducing the quality of life of the patient. Among the main radiotherapeutic techniques used in Brazil, IMRT and VMAT are characterized as the most advanced forms of 3D therapy, providing equivalent doses for each area of the tumor sparing surrounding tissue areas that do not require irradiation. In addition to reduced toxicity, greater survival can be observed in patients treated with these techniques. One of the biggest current challenges in radiation therapy against CCP is the protection of healthy tissues. In this sense, the IMRT and VMAT present superiority in relation to the other techniques.
Subject(s)
Oral Manifestations , Radiation , Radiation, Ionizing , Radiotherapy/adverse effects , Head and Neck Neoplasms/radiotherapyABSTRACT
La radioterapia de cabeza y cuello posee un rol central en el tratamiento de las neoplasias otorrinolaringológicas, ya sea como tratamiento adyuvante a la cirugía o como terapia definitiva. Dentro de este campo de estudio, un tópico aún poco explorado y motivo de debate, es la indicación de irradiación de los ganglios linfáticos retrofaríngeos, correspondientes a los niveles VIIa y VIIb de cuello. Hemos llevado a cabo una revisión sistemática con el objetivo de dilucidar criterios de irradiación electiva de estos grupos nodales y de emitir recomendaciones en cuanto a su inclusión en la práctica de la radio-oncología.
Radiation therapy has a central role in the management of head and neck malignancies, either as adjuvant treatment after surgery or as definitive therapy. Within this field of study, a still poorly explored and matter-of-debate topic is the indication for irradiation of retropahyngeal lymph nodes, corresponding to neck levels VIIa and VIIb. We have conducted a systematic review with the objective of elucidating elective irradiation criteria for these nodal groups and to issue recommendations about its inclusion in the practice of radiation oncology.
Subject(s)
Humans , Otorhinolaryngologic Neoplasms/radiotherapy , Lymph Nodes , NeckABSTRACT
Background and purpose:In recent years,domestic radiotherapy equipment and related software have made great progress,and testing the functionality and stability of the equipment and software is an essential step.This paper focused on comparing the differences in intensity-modulated radiation therapy(IMRT)plans dosimetry and organ at risk(OAR)volume calculations for common cancers between uRT-treatment planning system(TPS)and Monaco-TPS,and to evaluate the feasibility of dose calculation for Infinity linac(linear accelerator,Elekta,Sweden)using uRT-TPS.Methods:Twenty cases of rectal cancer,lung cancer,breast cancer and nasopharyngeal carcinoma were selected.The IMRT plans were completed in uRT-TPS and Monaco-TPS.The dose uniformity and conformity,mean dose,maximum dose of planning target volume(PTV)and OAR between two plans under the same prescribed dose of PTV were compared.And the pass rates of two TPS plans validated at the same linear accelerator were compared.Meanwhile,monitor units(MU),source skin distance(SSD)and the volume of OAR in uRT-TPS and Monaco-TPS were compared.Results:Wonderful plans that met the clinical requirements were obtained in uRT-TPS and Monaco-TPS.Comparable uniformity and conformability was received in PTV,and the maximum dose of PTV was reduced by 1.1 Gy for uRT-TPS(P = 0.006).For breast cancer and lung cancer,the dose in lung was lower for Monaco-TPS(P＜0.05).For nasopharyngeal carcinoma,the dose indicators that oral cavity and throat in the uRT-TPS was reduced by 9.2%and 5.1%,respectively.The verification results of absolute point dose(＜3%)and three-dimensional surface dose(＞95%)for both plans met the clinical requirements.The region of interest in uRT-TPS was smaller compared with Monaco-TPS(P＜0.05).Conclusion:A comparable IMRT plan was obtained for common tumors in uRT-TPS and Monaco-TPS.It is feasible to calculate the dose of Infinity linac using uRT-TPS.
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AIM:To investigate the role of ClC-3 chloride channel in the promotion of radio sensitization of na-sopharyngeal carcinoma CNE-2Z cells by dihydroartemisinin(DHA).METHODS:MTT was used to detect the inhibito-ry effect of DHA on the viability of CNE-2Z cells and normal nasopharyngeal epithelial NP69-SV40T cells,the radio sensi-tization effect of DHA on CNE-2Z cells was detected by cloning assay,the expression of ClC-3 protein was detected by Western blot,the expression of ClC-3 protein was down-regulated by siRNA technology,and the chlorine current of cells was recorded by whole cell patch-clamp technology.RESULTS:(1)Compared with NP69-SV40T cells,DHA selective-ly inhibited the proliferation of CNE-2Z cells,with IC10 values of(13.020±4.831)μmol/L and(5.244±1.050)μmol/L,respectively(P＜0.01).(2)The results of clonal formation experiments showed that DHA had a radio sensitizing effect on CNE-2Z cells,with a radio sensitization ratio of 1.9.(3)DHA could activate the chlorine channel of CNE-2Z cells and produce an outward chlorine current,but had no effect on the chlorine channel of NP69-SV40T cells.(4)DHA promoted the expression of ClC-3 chloric channel protein in CNE-2Z cells(P＜0.01).(5)Chlorine channel blocker NPPB could in-hibit the radio sensitizing effect of DHA on CNE-2Z cells by 1.84 times,and also inhibited the chlorine current activated by DHA.(6)the down-regulation of CNE-2Z ClC-3 protein could inhibit the radio sensitization effect of DHA on CNE-2Z cells by 4.19 times,and the activation of chlorine current by DHA on CNE-2Z cells was no longer produced.CONCLU-SION:DHA has a radio sensitizing effect on nasopharyngeal carcinoma CNE-2Z cells,which is likely to be related to the activation of ClC-3 chloride channel.
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Objective:To investigate the value of peripheral blood neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and serum lactate dehydrogenase (LDH) levels for predicting the occurrence of radiation pneumonia (RP) in small cell lung cancer.Methods:A total of 84 patients with small cell lung cancer who received image-guided radiotherapy in Xuzhou Cancer Hospital between September 2019 and September 2022 were retrospectively analyzed. They were divided into an RP group ( n = 25) and a non-RP group ( n = 59) according to whether RP occurred. Peripheral blood NLR and PLR and serum LDH levels were compared between the two groups before and after radiotherapy. The receiver operating characteristic curve (ROC curve) was used to analyze the value of peripheral blood NLR, PLR, and serum LDH levels for the diagnosis of RP in small cell lung cancer. Results:Before radiotherapy, there were no significant differences in peripheral blood NLR and PLR between the two groups (both P > 0.05). After radiotherapy, peripheral blood NLR and PLR in the RP group were (3.39 ± 0.81) and (129.06 ± 24.90), respectively, which were significantly higher than those in the non-RP group [(2.54 ± 0.71), (104.76 ± 26.26), t = 3.61, 3.83, both P < 0.05]. The NLR (2.86 ± 0.30) and PLR (110.07 ± 10.05) were the lowest in patients with grade 2 RP and they were highest in patients with grade 4 RP [(4.49 ± 0.63), (168.88 ± 14.11)]. The grade of RP was positively correlated with peripheral blood NLR and PLR. The sensitivity of peripheral blood NLR in the diagnosis of RP was 88.0%, the specificity was 66.1%, and the area under the curve (AUC) was 0.791. The sensitivity of PLR in the diagnosis of RP was 48.0%, the specificity was 94.9%, and the AUC was 0.735. The sensitivity of NLR combined with PLR in the diagnosis of RP was 92.0%, the specificity was 59.3%, and the AUC was 0.801. There was no significant difference in serum LDH levels between the two groups before and after radiotherapy (both P > 0.05). Logistic regression analysis showed that NLR and PLR were risk factors for RP in patients with small cell lung cancer ( OR = 2.309, 1.037; 95% CI: 1.061-5.024, 1.004-1.071). Conclusion:In patients with small cell lung cancer who develop RP, peripheral blood NLR, and PLR are markedly elevated compared with those in patients who do not develop RP, and combined detection of peripheral blood NLR and PLR has a high value for early diagnosis of RP in patients with small cell lung cancer.
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Objective To investigate the efficacy and safety of intensity-modulated radiation therapy combined with camrelizumab in the treatment of advanced hepatocellular carcinoma(HCC).Methods A total of 84 patients with advanced HCC admitted to our hospital from January to December 2020 were selected as the study objects,and were randomly divided into the observation group and the control group,with 42 cases in each group.Patients in the observation group received intensity-modulated radiation therapy combined with carrelli-zumab,and patients in the control group received intensity-modulated radiation therapy.The short-term efficacy,immune function and long-term survival rate of patietns in the two groups were compared,and the incidence of adverse reactions was recorded.Results The total effec-tive rates of the observation group 1 month and 3 months after treatment were significantly higher than those of the control group(P<0.05).The levels of CD3+,CD4+ and CD4+/CD8+ 1 month and 3 months after treatment were all increased in the two groups,while the levels of CD8+ in both two groups were decreased(P<0.05),and the levels of CD3+,CD4+ and CD4+/CD8+ in the observation group were higher than those in the control group(P<0.05),and the levels of CD8+ in the observation group were lower than those in the control group(P<0.05).The median survival time of patients in the observation group was significantly longer than that of patients in the control group(P<0.05).The incidence of cutaneous capillary hyperplasia in the observation group was higher than that in the control group(P<0.001),and there was no significant difference in the incidence of other adverse reactions between the two groups(P>0.05),and all of adverse reactions were grades 1 to 2.Conclusion Intensity-modulated radiation therapy combined with camrelizumab has a good effect on HCC,it can improve the immune function of the body,and control the development of the disease,with good safety.
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Objective To compare patient radiation dose during implantation of the second generation wireless pacemaker(Micra AV)and traditional dual-chamber pacemaker.Methods Data of 74 patients who received pacemaker implantation for bradycardia were retrospectively analyzed.According to the kind of pacemaker,the patients were divided into AV group(n=30)and traditional group(n=44).The perspective time,air kerma(AK),dose area product(DAP),number of movie sequences and total movie frames were compared between groups.Results AK,movie DAP,number of movie sequence and total movie frames in AV group were all higher than those in traditional group(all P＜0.05).No significant difference of the perspective time nor perspective DAP was found between groups(both P＞0.05).Patients'X-ray radiation projection range were essentially the same in both groups,most distributing on the left side of the bodies.Conclusion Compared with implantation of traditional dual-chamber pacemaker,implantation of Micra AV brought patient greater radiation dose from movie acquisition,while radiation dose from fluoroscopy were not significantly different.
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Exposure to ionizing radiation intervenes in genomic stability and gene expression,resulting in the disruption of normal metabolic processes in cells and organs by causing complex biolog-ical responses.Altered genomic variations,gene expression and metabolite concentrations in blood or tissue samples reflect systemic radiation damage.With the application of new techniques and exten-sive study on the mechanisms for ionizing radiation damage,related indicators such as chromosomal variation,gene expression,lipid and metabolism are being recognized and promise to be the markers for early diagnosis and prognosis of radiation exposure.Therefore,this article reviews recent progress in and potential applications of biomarkers related to ionizing radiation injury.
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Objective To explore the correlations between image quality of prospective and retrospective electrocardiogram(ECG)-gated CT coronary angiogram and radiation dose in patients with different heart rates.Methods A total of 135 patients undergoing 256-slice spiral CT coronary angiography were enrolled in the study.Among them,66 cases received prospective ECG-gated scanning(prospective ECG-gated group)and further divided into two subgroups with heart rate≤80 beats/min(prospective ECG-gated+low heart rate subgroup,n=39)and>80 beats/min(prospective ECG-gated+high heart rate subgroup,n=27).The other 69 cases underwent retrospective ECG-gated scanning(retrospective ECG-gated group),including 45 cases with heart rate≤80 beats/min(retrospective ECG-gated+low heart rate subgroup)and 24 with heart rate>80 beats/min(retrospective ECG-gated+high heart rate subgroup).The baseline data,image quality[mean CT value,image noise,signal-to-noise ratio(SNR),subjective image quality score]and radiation dos[CT volume dose index(CTDIvol),dose length product(DLP),effective dose(ED)]were compared among 4 subgroups.The correlations of image quality with heart rate and radiation dose in prospective and retrospective ECG-gated groups were analyzed.Results The heart rates in prospective and retrospective ECG-gated+low heart rate subgroups were lower than those in prospective and retrospective ECG-gated+high heart rate subgroups(P<0.05).When comparing the mean CT value,image noise,SNR and subjective image quality score among 4 subgroups,no statistically significant differences were observed(P>0.05).The CTDIvol,DLP and ED in prospective ECG-gated+low heart rate subgroup were significantly lower than those in the other 3 subgroups(P<0.05),and the indicators in prospective ECG-gated+high heart rate subgroup were lower than those in retrospective ECG-gated group(including low and high heart rate subgroups)(P<0.05).Pearson correlation coefficient analysis revealed that the mean CT value,image noise,SNR,subjective image quality score had no significant correlation with heart rate,CTDIvol,DLP and ED in prospective and retrospective ECG-gated groups(P>0.05).Conclusion The subjective and objective image quality of 256-slice spiral CT coronary angiography is not correlated with radiation dose.Prospective ECG-gated scanning can reduce the radiation dose and ensure the image quality as compared with retrospective ECG-gated scanning.This holds true for eligible patients with high heart rate,and the former can effectively reduce radiation exposure.Therefore,prospective ECG-gated scanning is worthy to be promoted in clinic.
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Purpose To evaluate the image quality improvement of deep learning iterative reconstruction(DLIR)on pediatric head CT images of head injury and to evaluate the performance of DLIR and conventional adaptive statistical iterative reconstruction-veo(ASIR-V)of noise and image texture of CT image in children's head trauma.Materials and Methods A total of 80 cases in Beijing Children's Hospital,Capital Medical University from December 7th to 11th 2020 of children's head low-dose CT were retrospectively selected.Scan voltage was 120 kV.Scan current was 150-220 mA.The raw data were reconstructed into 5 mm thick slice and 0.625 mm thin slice brain window and bone window images.50%ASIR-V and high weight DLIR images(DL-H)were reconstructed,respectively.A 4-point system was used to subjectively evaluate the display of sulcus,brain matter and bone.The number of lesions in each group was counted.The CT value and image noise values of gray matter and white matter were measured,and the contrast to noise ratio was calculated,then measured the blur metric index was measured in the same slice.The differences between the two image reconstruction methods were compared.Results Compared to 50%ASIR-V images,DL-H significantly improved the display ability of the sulcus and ventricles,as well as the display ability of the brain parenchyma(W=5.5-22.2,all P<0.05)in both slice thickness.There was no statistically significant difference in the display ability of the sulcus and ventricles between 5 mm 50%ASIR-V and 0.625 mm DL-H images(W=0.9,2.0,P=0.32,0.05,respectively).In terms of bone display ability,all images could achieve a maximum score of 4.0.A total of 35 lesions were found in 80 patients via 5 mm 50%ASIR-V and DL-H images,including 12 hemorrhagic lesions,1 intracranial gas,9 fractures,and 13 soft tissue swelling.In terms of objective evaluation,the noise level of DL-H images was significantly lower than that of 50%ASIR-V images(t=21.4-35.7,all P<0.05),and there was no statistically significant difference in noise and contrast noise ratio between 5 mm 50%ASIR-V and 0.625 mm DL-H images(t=1.7-2.2,all P≥0.05).The blur metric index showed that DL-H was superior to 50%ASIR-V images(t=6.1,10.0,both P<0.05),and there was no statistically significant difference in blur metric index between 0.625 mm DL-H and 5 mm 50%ASIR-V images(t=2.6,P=0.28).Conclusion DLIR can improve the CT image quality and image texture of children's head trauma,0.625 mm DL-H image quality is close to 5 mm 50%ASIR-V image,which can meet the diagnostic requirements,and possible to further reduce the radiation dose.
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Objective:To study the feasibility and value of applying organ dose modulation technique in computed tomography(CT)scanning on eyes.Methods:A total of 330 patients who admitted to Beijing Friendship Hospital affiliated with Capital Medical University from August 2021 to August 2023 and underwent CT examination on eyes were selected.They were divided into modulation group,conventional group and low-dose group based on the control methods of tube current in scanning.The modulation group used organ dose modulation technique with intelligent automatic tube current of 70-150 mA,and the conventional dose group used a fixed tube current of 100 mA,and the low-dose group used a fixed tube current of 70 mA.The differences in radiation dose and CT imaging quality among 3 groups were compared.Results:The dose length product(DLP),volume CT dose index(CTDIvol)and effective dose(ED)of cross-sectional scan of the modulation group were respectively 62.37,12.83 and 0.143 mSv,which were significantly lower than 115.23,18.93 and 0.265mSv of conventional dose group,respectively,with statistically significant(F=2544.944,6009.596,2544.944,P<0.05).The DLP,CTDIvol and ED of coronary scan of the modulation group were 68.19,13.15 and 0.156,respectively,which were significantly lower than 122.41,19.20 and 0.282 mSv of the conventional dose group,respectively,with statistically significant(F=1232.413,3813.940,1232.413,P<0.05).The excellent rates of cross-sectional scans among the modulation group,conventional group and lower-dose group were respectively 98.83%,86.15%and 47.69%,and the difference among three groups was statistically significant(x2=53.908,P<0.05).The excellent rates of image qualities of the modulation group,conventional group and low-dose group were respectively 96.61%,80.70%and 48.28%,and the difference among three groups was statistically significant(x2=20.992,P<0.05).Conclusion:The application of organ dose modulation technique in CT scanning on eyes can significantly reduce radiation dose on patient under ensures imaging quality can meet diagnostic needs when undergoes cross-sectional and coronal scans,which has higher clinical feasibility and application value.
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Objective:To make an individual phantom that was printed by using three dimension(3D)technique,which could reflect the real situation of patient,and to analyze the computed tomography(CT)value and dose distribution of radiotherapy on each organ of the inside of the 3D-printed individual phantom.Methods:According to the localization of CT image of the patient,the empty shell of 3D structure of each organ were reconstructed and printed by using 3D technique.The CT value was used as basis to select the equivalent material of each organ to perform fill,which could obtain the individual phantom of chest that could appear the structural characteristics of patient.The treatment plan of patients were included in treatment plan group,and the plans which were transplanted to 3D-printed individual phantom from treatment plan of patients were included in phantom plan group.The dosimetric parameters of the plans of two groups were compared.Results:The average CT values of left and right lung,soft tissue,cancellous bone,compact bone and heart of the phantom plan group were respectively-709,-737,14,144,760 and 28 HU.The errors of the all CT values between phantom images and located images of patients were less than 16.7%.The exposure doses of normal tissues of radiotherapy plans on the images of two groups could meet the clinical requirements.The minimum dose(Dmin),mean dose(Dmean),the corresponding doses of 98%,50% and 2% target volumes(D98%,D50% and D2%),conformity index(CI),homogeneity index(HI),monitor unit(MU)of dosimetric parameters of the target region could meet the clinical requirements without statistically significant differences.There was significant differences in the maximum dose(Dmax)of the target region(t=2.678,P＜0.05).Among of these Dmax values,the Dmax value of phantom plan group was larger,which was(56.97±0.32)Gy.Conclusion:The CT value,tissue structure and spatial distribution of the phantom,which is finally designed,can emulate the chest of human body in radiotherapy.It has verified the feasibility that 3D-printed phantom is applied in measuring dose in the quality assurance of radiotherapy.
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Objective:To explore the changes of oxidative stress(OS),DNA damage and the occurrence of cellular premature aging of human immortalized keratinocytes(HaCaT)after that was radiated by X-ray with different doses.Methods:HaCaT cells were radiated by X-ray,and they were divided into 0 Gy group,5 Gy group and 10 Gy group according to the irradiation dose.The levels of intracellular reactive oxygen species(ROS)were detected by 2,7-Dichlorofluorescein diacetate(DCFH-DA)fluorescent probe,and the intracellular content of malondialdehyde(MDA)of lipid peroxidation products and the activity of superoxide dismutase(SOD)were measured by colorimetry.Immunofluorescence staining was used to detect the phosphorylated histone 2A variant(γ-H2AX)in HaCaT cells that were radiated by X-ray with different doses.Cell count kit-8(CCK-8)was used to detect the effect of X-ray with different doses on the proliferation of HaCaT cells after X-ray with different doses radiated them.β-Galactosidase staining was used to detect the proportion of premature aging cells.The changes of p21 and p53 protein expressions after X-ray irradiation were detected by Western blot.Results:After HaCaT cells were radiated by X-ray for 24h,the fluorescence intensity of 2',7'-Dichlorofluorescein(DCF)in 5 Gy and 10 Gy groups were significantly higher than that in the 0 Gy group,and the MDA contents of them were significantly higher than that in the control group,and the SOD activities of them were significantly lower than that in the control group(F=38.35,92.22,5.22,P<0.05),respectively.The change of γ-H2AX focus showed a dose-dependent significant increase at 1 h after irradiation,and the difference between them and control group was statistically significant(F=129.3,P<0.05).At 6h,24h and 48h after X-ray radiated HaCaT cells,the cell proliferation abilities of 5 Gy group and 10 Gy group were significantly decreased than that of 0 Gy group(F=116.41,62.20,34.29,P<0.01),and the β-Galactosidase activity of the two groups were significantly increased than that of 0 Gy group,and the difference was significant(F=1629.22,P<0.01).At 72h after X-ray with different doses radiated HaCaT cells,the expression levels of p21 and p53 proteins of 5 Gy group and 10 Gy group increased,and the differences of them among three groups were significant(F=104.4,66.69,P<0.01),respectively.Conclusion:Ionizing radiation can induce the occurrences of oxidative stress and DNA damage in HaCaT cells,and cause the occurrence of cellular premature aging.
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Objective:To investigate the effects of different tube voltages combined with artificial intelligence reconstruction algorithm(CI)on the computed tomography(CT)imaging quality and radiation dose of chest phantom on the basis of the CT scan for an adult male simulated chest phantom(PH-N1).Methods:A 512-slice CT scanner of ultrahigh-end was adopted to conduct scan,and the images were divided into 70 kV group,80 kV group,100 kV group and 120 kV group according to different tube voltage.For 4 groups of CT scan images with different tube voltages,the 10%,30%,50%,70%and 90%CI were adopted to reconstruct 1mm thin layer image.The CT volume dose index(CTDIvol)and the dose-length product(DLP)of the scans of 4 groups were compared.The CT values and standard deviation(SD)values of the aorta,abdominal wall fat and erector spine muscle were measured.Two senior diagnostic physicians with more than 5 years of work experience independently and double-blindly evaluated the image quality by using 5-point scale.A Kappa consistency test was conducted.One-way analysis of variance was adopted to compare the differences of CT values and SD values of the tissues of image targets.The Friedman rank-sum test was adopted to compare the differences of subjective image qualities among different groups.Results:The differences of CTDIvol and DLP among 4 groups with different tube voltages were significant(F=1855.617,3996.118,P<0.05),respectively.Under 70 kV tube voltage,there were no significant differences in CT values of the aorta,abdominal wall fat and erector spine muscle,which were reconstructed by using 10%,30%,50%,70%and 90%CI(P>0.05),while the differences of SD values among them were statistically significant(F=32.267,53.327,14.873,P<0.05),respectively.Under the different tube voltages of 4 groups,which were reconstructed by 90%CI,the CT values of aorta,abdominal wall fat and erector spine muscle gradually decreased with decreasing of tube voltage,the differences were significant(F=139.899,2563.93,219.231,P<0.05),respectively.The consistency of subjective scores between two diagnostic physicians was better for each group of images(Kappa=0.712～0.869).Conclusion:Compared with 80 kV,90 kV and 120 kV images,the reconstructed images with 90%CI algorithm under 70 kV tube voltage can significantly reduce the radiation dose,and the images have a favorable signal-to-noise ratio at the same time.
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Objective:To investigate the incidence of radiation pneumonitis (RP) induced by 125I seed implantation for the treatment of malignant lung tumors and analyze related dosimetric parameters. Methods:A retrospective analysis was conducted on 31 cases of malignant lung tumors treated with 125I seed implantation from January 2017 to December 2022 at Hebei Provincial Tumor Radioactive Seeds Implantation Diagnosis and Treatment Center. These cases consisted of eight patients with squamous cell carcinoma, 10 patients with adenocarcinoma, and 13 patients with metastatic cancer in other sites. At 1-6 months after treatment, these patients received postoperative chest CT scans, with the efficacy evaluated based on the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1), including the objective response rate (ORR) and the disease control rate (DCR). The efficacy of RP was evaluated using the Radiation Therapy Oncology Group (RTOG) criteria. Postoperative dosimetric parameters, including D90 (minimum peripheral dose received by 90% of the target volume), V8 (percentage of lung volume receiving 8 Gy), V32 (percentage of lung volume receiving 32 Gy), and Dmean (mean radiation dose) of the affected lung, were statistically analyzed. The relationships of the RP occurrence with postoperative D90, V8, V32, and Dmean were analyzed by comparison with relevant external radiotherapy data, to identify the parameters that are correlated closely with RP occurrence. Results:All the patients underwent successful surgeries. The postoperative efficacy evaluation after six months showed complete response (CR) in 11 cases, partial response (PR) in 11 cases, stable disease (SD) in eight cases, and progressive disease (PD) in one case, with an overall response rate (ORR) of 71.0%, and a disease control rate (DCR) of 96.8%. Three patients suffered RP, with an incidence rate of 9.7%. Postoperative V8, V32, and Dmean could not serve as predictive indicators for RP. Follow-up observation revealed that three RP cases (3/5) exhibited postoperative D90 exceeding 170 Gy and no RP cases (0/26) showed postoperative D90 below 170 Gy. Conclusions:In the treatment of malignant lung tumors with 125I seed implantation, there is a certain correlation between RP and postoperative D90, while there is no correlation between it and V8, V32, and Dmean.
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Objective:To investigate the trend of radiological diagnostic examination frequency and the related influencing factors in a general hospital in recent four years.Methods:The hospital information system and the radiology information system were used to collect the information on the numbers of the outpatients, the emergency patients, and the inpatients and the radiology examination information from 2019 to 2022. The examination frequency and proportion of various imaging equipment were counted by using the perspective table of data, and the examination items and the proportion of the radiological diagnostic examinations were calculated. The positive rates of the radiological examinations were measured from 2019 to 2022. The gender and age distribution of the patients were analyzed. Spearman correlation analysis was used to analyze the relationships between the numbers of the patients undergoing radiological examinations and the numbers of the outpatients, emergency patients and the inpatients.Results:The annual frequency of radiological diagnostic examinations from 2019 to 2022 were 307 306, 245 418, 317 250 and 325 625, respectively, with a total of 1 195 599. Among them, the proportions of CT, X-rays, bedside X-rays, bone density, gastrointestinal imaging and mammography were 59.74%, 38.04%, 1.39%, 0.42%, 0.21% and 0.19%, respectively. In each year, the proportion of CT in all radiological diagnostic examinations was 49.58%, 63.40%, 60.40% and 65.20%, respectively. The frequency of emergency CT and emergency chest CT was correlated with the number of emergency patients( r =0.63, 0.61, P<0.05), and the frequency of non-emergency CT was correlated with the number of outpatients and inpatients ( r =0.61, 0.66, P<0.05). The positive rates of the CT examinations were higher than 80% except the lowest of 79.95% in 2021. Conclusions:Radiological examinations especially CT examinations have increased significantly, and played an important role in the diagnosis of diseases. However, attention should be paid to the Justification of the CT examinations. Timely statistical analysis of radiological examination information can provide data supports and references for scientific management of radiological examinations.
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Objective:To explore the radiological protection measures for yttrium-90 ( 90Y)-loaded resin microsphere therapy in clinical application. Methods:The surgical operation process for 90Y-loaded resin microsphere therapy was simulated, involving measurement of ambient dose equivalent rates at various stages: preoperative preparation (dominated by drug package), drug transfer, intraoperative procedures (drug operation and injection), and postoperative care and observation within the hospital. Based on the simulation, the protection measures in clinical application were analyzed. Results:The dose equivalent rate ranged from 0.12 to 0.42 μSv/h around the active chamber and from 1.04 to 3.32 μSv/h in the fume hood. Around the digital subtraction angiography (DSA) room, the maximum dose equivalent rate was 0.78 μSv/h when 90Y and DSA were applied simultaneously and 0.36 μSv/h when 99Tc m and DSA were applied. For the first operating position in the fluoroscopy protection area, the maximum dose equivalent rate was 13.19 μSv/h at 155 cm height when only 90Y was applied, and 315.01 μSv/h at 80 cm height when 90Y and DSA were applied. For the second operating position, the maximum dose equivalent rate was 6.28 μSv/h at 155 cm height when only 90Y was applied and 291.03 μSv/h at the same height when 90Y and DSA were applied. The dose-equivalent rates ranged from 0.11 to 0.58 μSv/h around the dedicated ward for postoperative patients. Conclusions:The existing shielding measures, such as those in the nuclear medicine department and interventional room, meet the radiation protection requirements for 90Y-loaded resin microsphere therapy. However, it is still necessary to conduct a scientific assessment based on the actual situation. Additionally, radiation protection measures and surface contamination treatment should be enhanced during drug operation.
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Objective:To evaluate the feasibility of low radiation dose and low contrast dosage in coronary CT angiography (CCTA) of class I obese patients.Methods:This prospective study enrolled 57 patients (male/female, 50/7, age, 25-77 years) with body mass index (BMI) of 30-38 kg/m 2 and body weight of 85-119 kg scheduled for CCTA from August 2022 to March 2023 in our hospital. The patients were divided into two groups: control group (group A, n = 20) and low-dose group (group B, n = 37). Group A employed a standard-dose protocol: tube voltage 120 kVp and IDR 2.2 g I/s, while group B were scanned using the low-dose protocol: tube voltage 100 kVp and IDR 1.5 g I/s. Images in Group A and Group B were reconstructed with hybrid iterative reconstruction (HIR) at strength 4 and 8, respectively. Other scanning and reconstruction parameters were the same in two groups. Methods:The image quality was assessed by measuring the CT values and noise in the aortic root, left anterior descending artery and right coronary artery, and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. Subjective image quality was evaluated for vessels according to the 18-segment classification system using a 4-point scale (1. poor, 4. excellent). The effective dose E and contrast dosage were compared. Statistical analysis was performed using independent samples t-test, Mann-Whitney U test or χ 2 test. Results:The BMI of groups A and B were 31.89 (30.77, 33.81) and 31.22 (30.46, 32.83) kg/m 2, respectively ( P>0.05). No statistically significant differences in CT values, noise, SNR, CNR were noticed between the two groups (all P>0.05). The mean subjective score of all coronary artery segments in the two groups were not less than 3, meeting the requirement of clinical diagnosis. There was no statistically significant difference in the overall subjective image quality between the two groups ( P>0.05). The radiation dose E in groups A and B were 7.58 and 4.49 mSv, respectively ( Z=-5.46, P<0.05). The contrast dosage in groups A and B were 66 and 45 ml, respectively. The radiation dose E and contrast dosage in group B were 41% and 32% lower than that in group A, respectively. Conclusions:For class I obese patients, it was feasible to use a low tube voltage (100 kVp) and low IDR (1.5 gI/s) protocol in CCTA. Radiation dose and contrast dosage can be reduced reasonably without compromising the CCTA image quality.
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Objective:To assess the radiation dose and clinical value of "one-stop" whole-brain CT perfusion (CTP) imaging in the evaluation of collateral circulation for patients with acute ischemic stroke (AIS), regarding the digital subtraction angiography (DSA) as the reference.Methods:This retrospective study included 32 AIS patients, for whom both CTP and DSA were obtained <24 h since onset. All CTP scans were acquired in whole-brain volume perfusion mode using a 320-row CT with the phase-specific settings of tube currents to optimize the image quality of CTA images, where multiple-phase (mp) CTA images were extracted from the CTP data in post-processing. The volume CT dose index (CTDI vol), dose length product (DLP), and effective dose were compared to those reported in previous studies. The perfusion parameters of the infarct lesions and their contralateral regions were compared using the paired t-tests. One radiologist scored the collateral circulation with only the CTP and with the CTP plus mp-CTA using a 5-point scale. Another radiologist performed the same evaluation on the DSA. The diagnostic accuracy was calculated referring to the result based on DSA. The scores were analyzed using the Pearson correlation coefficient. The agreement of scores was quantified with the Kappa test. Results:The mean CTDI vol was 184.18 mGy, which was comparable to the result of a previous study (184.19 mGy), and the mean effective dose was reduced 39% compared to that reported in the literature for combined CTP and CTA scanning (6.1 vs 10 mSv). There were statistically significant differences in cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), transit time to peak (TTP), and time-to-maximum (Tmax) between the infarct lesions and their contralateral regions ( P<0.01). The scores between CTP and DSA were significantly correlated ( r=0.95, P<0.01), as well as the scores between CTP plus mp-CTA and DSA ( r=0.98, P<0.01). The Kappa value was 0.64 ( t=7.53, P<0.01) between CTP and DSA, while it increased to 0.88 ( t=9.99, P<0.01) for CTP plus mp-CTA. With the result of DSA as a reference, the diagnostic accuracy was 71.9% and 90.6% for CTP and CTP plus mp-CTA, respectively. Conclusions:The "one-stop" whole-brain CTP imaging with phase-specific settings of tube currents can provide reliable CTP and multiple-phase CTA images simultaneously, which could reasonably reduce the radiation dose. Combined use of multi-phase CTA and CT perfusion improves the diagnostic accuracy of collateral circulation in AIS patients.
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Objective:To explore the differences between the deep learning-based image reconstruction (DLIR) and the adaptive statistical iterative reconstruction V (ASiR-V) algorithms in the radiation dose and image quality of head and neck CT angiography (CTA).Methods:The data of 80 patients undergoing head and neck CTA due to vascular diseases in the head and neck were prospectively collected. These patients were randomly divided into groups A and B based on their examination sequence. The CTA images of group A were reconstructed based on ASiR-V 50%, with a tube voltage of 120 kV and a noise index of 11.0. In contrast, those of group B were reconstructed based on ASiR-V 50% (for group B1) and DLIR-H (for group B2), with a tube voltage of 80 kV and a noise index of 9.0. Then, the radiation doses and image quality of both groups were compared using the independent-sample t-test. The radiation doses, and both subjective and objective image quality of the two imaging method were compared through the Kruskal-Wallis test and the Wilcoxon rank-sum test. The independent- or paired-sample t-test was employed to measure inter-group vascular enhanced CT values, as well as signals and noise from regions of interest (ROIs), with signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) calculated. Results:The effective doses of groups A and B were (0.77±0.08) and (0.45±0.05) mSv, respectively, with a statistically significant difference ( t = 21.96, P < 0.001). The vascular enhanced CT values, SDs, SNRs, and CNRs in the arch of the aorta, the initial and bifurcation parts of the common carotid artery, and the M1 segment of the middle cerebral artery showed statistically significant differences among groups A, B1, and B2 ( F = 67.69, 68.50, 50.52, 74.10, 63.10, 91.22, 69.16, P < 0.001). Additionally, statistically significant differences were observed in the subjective scores of image quality among groups A, B1, and B2 ( Z = 71.06, P < 0.05). Conclusions:The DLIR algorithm can further reduce the radiation dose in head and neck CTA examination while significantly reducing image noise and ensuring image quality, thus demonstrating high clinical application value.