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Objective:To evaluate the application value of SPECT lung perfusion imaging in guiding radiotherapy path, optimizing the radiotherapy plan for lung cancer and protecting lung function during radiotherapy for locally advanced non-small cell lung cancer.Methods:In this study, 84 patients with stage Ⅲ non-resectable non-small cell lung cancer were randomly divided into the control group ( n=44) and observation group ( n=40). In the control group, radiotherapy plan based on conventional CT images was delivered, and two plans based on the lung function information suggested by conventional CT and SPECT lung perfusion imaging: P1 and P2 were given in the observation group. All patients in the observation group were finally treated according to the P2 plan. The incidence of radiation pneumonitis, and changes in lung function before and after radiotherapy were statistically compared between two groups. The dose-volume parameters of P1 and P2 were statistically compared. Results:After the plan was optimized, the incidence of radiation pneumonitis in the observation group was significantly reduced and the decline of lung function was significantly improved (both P≤0.001). The functional dose parameters were significantly improved in the P2 plans (both P<0.05), whereas the irradiation dose of organs at risk did not significantly change ( P>0.05). Conclusion:SPECT lung perfusion imaging optimizes the intensity-modulated radiotherapy plan, which can reduce the functional lung dose and increase the tumor radiotherapy dose without increasing the irradiation dose of other organs at risk.
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Objective To discuss the value of dual-input perfusion of 320 row CT on the efficacy evaluation of small cell lung cancer (SCLC).Methods A total of 18 patients with SCLC confirmed by pathology who received cisplatin plus etoposide chemotherapy between June 2016 and June 2018 in the 8th Medical Center of Chinese PLA General Hospital were collected.All patients received 320 row CT perfusion scan at 3 time points before chemotherapy,after 2 cycles and 4 cycles of chemotherapy.Tumor size,perfusion pseudo color map and bronchial arterial blood flow (BF),pulmonary flow (PF) and perfusion index (PI) were obtained.The efficacy and adverse reactions were evaluated.The single factor analysis was used to make the group comparison.Pearson test was used to make correlation analysis.Results Two patients after 2 cycles of chemotherapy had complete remission (CR),another 2 patients after 4 cycles of chemotherapy had CR,and 3 patients of the above 4 cases with CR had abundant BF;after 4 cycles of chemotherapy,7 cases had partial remission (PR),6 cases had stable disease (SD),1 patient had progression of disease (PD).Dual-input perfusion of 320 row CT showed that 10 cases had the tumor area ＜ 15 cm2 and 8 cased had the tumor area ＞15 cm2 before the treatment.There was a negative correlation between PI and the tumor area (r =-0.694,P =0.026) on patients with the tumor area ＜ 15 cm2 before the treatment,and no correlation was found in patients with tumor area ＞15 cm2 (P ＞ 0.05).One case had Ⅳ degree of bone marrow suppression,and obvious adverse reactions were not seen in the rest of the patients.Conclusion Dual-input perfusion of 320 row CT based on the simple imaging can make an accurate quantitative judgement of the effect of SCLC according to perfusion parameter,which provides a new basis for curative effect evaluation on SCLC.
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Objective To evaluate the lung exposure dose-volume (DVH) parameters and other indicators of lung perfusion imaging before and after three-dimensional conformal or intensity modulated radiation therapy for lung cancer patients,and combined with clinical factors,to explore relationship with radiation pneumonitis occurred.Methods 18 patients were selected for data analysis.Lung perfusion scintigraphy was detected before and after three-dimensional conformal or intensity modulated radiation therapy for lung cancer.Lung perfusion changes were compared before and after irradiation.Evaluation of radiation pneumonitis was assessed by the Radiation Therapy Oncology Group (RTOG) acute radiation pneumonitis standard.After the CT and SPECT lung perfusion images were transferred to Varian,the Eclipse 3D treatment planning system,image fusion after dose curve projected onto the SPECT images,and the DVH was converted into a f-DVH diagram.Analysis of pulmonary perfusion imaging changes before and after radiotherapy combined with lung irradiation dose volume parameters and radiation pneumonitis.Results In the whole group,33.3 ％ (6/18) cases occurred more than 2 radiation pneumonitis.Before and after radiotherapy,the damage to the lung perfusion was more than 2 radiation pneumonitis incidence [62.5 ％ (5/8)],and impaired pulmonary perfusion improvement was 10.0 ％ (1/10).DVH parameters to V5 severe RP forecasted high accuracy.In curve for each patient,boundary values of V5,V10 and V20 were 53 ％,41％ and 27 ％.Before and after radiotherapy it was found that lung perfusion changes and the whole lung V5 portfolio were the strongest predictors for radiation pneumonitis after radiotherapy.Conclusion Pulmonary perfusion imaging in patients with lung cancer is able to reflect changes in the function of ipsilateral lung perfusion before and after radiotherapy.Changes in the ipsilateral lung perfusion detected before and after radiotherapy combined with V5 are expected to serve as indicators to predict radiation pneumonitis.
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Objective To evaluate the clinical value of radionuclide pulmonary perfusion imaging in diagnosing acute pulmonary embolism.Methods Radioactive pulmonary perfusion imaging was performed in 25 patients clinically suspected for acute pulmonary embolism,meanwhile,imaging of deep veins of lower limb was taken.Results Multiple segments of abnormal blood perfusion were found in 23 of 25 patients,among them,radioactivity defects were found in 41 segments,radioactivity rarefied areas were found in 84 segments.Deep venous thrombosis was detected in 6 patients.Conclusion Radionuclide pulmonary perfusion imaging is a non-invasive and effective method in diagnosing acute pulmonary embolism.