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Nuclear medicine physicists play an important role in nuclear medicine, and they are also a significant part of medical physicists. This study investigated the regulations and requirements of international organizations such as International Atomic Energy Agency (IAEA) and International Organization Medical Physics (IOMP)for medical physicists in nuclear medicine, and discussed the necessity, role, responsibilities and the quantity requirements of nuclear medicine physicists staffing in hospitals according to the demand for nuclear medicine physicists and the present situation of nuclear medicine physicists in China, so as to provide a reference for the work of nuclear medicine physicists in China.
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Objective To investigate the application value of dynamic single-photon emission computed tomography (SPECT) 99m-technetium galactosyl human serum albumin diethylenetriamine pentaacetic acid injection (99 Tcm-GSA) scintigraphy assessing regional liver function changes before and after portal vein embolization (PVE).Methods The retrospective cross-sectional study was conducted.The clinical data of 11 patients with Bismuth Ⅲ a hilar cholangiocarcinoma who were admitted to the General Hospital of People's Liberation Army (10 patients) and Beijing Tsinghua Changgung Hospital (1 patient) from October 2010 to October 2016 were collected.B ultrasound-guided percutaneous transhepatic ipsilateral exbolization was performed before radical resection of hilar cholangiocarcinoma.Dynamic SPECT 99 Tcm-GSA scintigraphy was performed to calculate and compare the changes of functional liver volume (FLV),morphological liver volume (MLV) and functional liver density (FLD) in embolized lobe and non-embolized lobe before PVE and 2 weeks after PVE.Observation indicators:(1) the changes of serum indexes in 2 weeks before and after PVE;(2) the changes of FLV,MLV and FLD in the whole liver,embolized and non-embolized lobes in 2 weeks before and after PVE;(3) surgical and postoperative situations of hilar cholangiocarcinoma;(4) follow-up and survival situations.Follow-up using outpatient examination and telephone interview was performed to detect postoperative serum toal bilirubin (TBil) level,with or without peritoneal effusion and survival up to June 2017.Measurement data with normal distribution were represented as x-±s.The comparisons of pre-and post-operative data were analyzed by the paired t test.Results (1) The changes of serum indexes in 2 weeks before and after PVE:11 patients underwent successful right PVE.The alanine aminotransferase (ALT),TBil,albumin (Alb),Platelets (PLT) and prothrombin time (PT) were respectively (113±20) U/L,(73± 8) μmol/L,(35.0±2.5) g/L,(209±58) × 109/L,(11.4±0.7) seconds in 2 weeks before PVE and (120± 18) U/L,(36± 7) μmol/L,(34.4± 3.2) g/L,(224± 82) × 109/L,(11.2±0.8)seconds in 2 weeks after PVE,with a statistically significant difference in TBil level (t=-10.592,P＜0.05) and no statistically significant difference in ALT,Alb,PLT and PT (t=0.981,-0.350,-0.591,0.533,P＞0.05).(2) The changes of FLV,M LV and FLD in the whole liver,embolized and nonembolized lobes in 2 weeks before and after PVE:the FLV,MLV and FLD of the whole liver were respectively (894±255) mL,(1 552±504) mL,0.59±0.14 in 2 weeks before PVE and (812±206) mL,(1 521±422) mL,0.55±0.16 in 2 weeks after PVE,with no statistically significant difference (t =1.569,0.666,1.980,P＞ 0.05).The FLV,MLV and FLD of the embolized lobe were respectively (623±275) mL,(1 047± 394) mL,0.62±0.14 in 2 weeks before PVE and (375±240) mL,(865±337) mL,0.44±0.24 in 2 weeks after PVE,with statistically significant differences (t =5.909,3.736,3.359,P ＜ 0.05);the descending percentages were respectively 38.1％,9.8％ and 24.6％.The FLV,MLV and FLD of the non-embolized lobe were respectively (274±152)mL,(530±176)mL,0.52±0.21 in 2 weeks before PVE and (436±149) mL,(656±133)mL,0.68± 0.24 in 2 weeks after PVE,with statistically significant differences (t =-6.019,-6.345,-3.933,P＜0.05);the elevated percentages were respectively 80.1％,19.9％ and 23.8％.(3) Surgical and postoperative situations of hilar cholangiocarcinoma:of 11 patients,10 received successful peri-hilar right hemihepatectomy,the right hepatic atrophy and an obvious demarcation line between left and right liver were found intraoperatively;1 stopped operation due to detect intraoperatively peritoneal metastasis of tumor.The operation time,volume of intraoperative blood loss and time of postoperative abdominal drainage-tube removal were respectively (585± 194)minutes,(472± 274)mL and (8±5)days.Of 10 patients undergoing operations,2 were complicated with massive peritoneal effusion at 2 days postoperatively,volume of peritoneal effusion remained more than 500 mL up to 7 days after drainage,and were improved by 1-month conservative treatment;other 8 patients were not complicated with hepatic dysfunction.Duration of hospital stay of 11 patients was (16± 4) days.(4) Follow-up and survival situations:10 patients were followed up for 4-72 months,with a median time of 39 months.During the follow-up,there was no evaluated TBil level and peritoneal effusion in 10 patients.The median survival time,1-,3-and 5-year overall survival rates were 88.8％,74.6％ and 36.8％,respectively.Conclusions The dynamic SPECT 99Tcm-GSA scintigraphy can effectively evaluate liver function changes of embolized and non-embolized lobes before and after PVE.The increased rate of FLV of non-embolized lobe is higher than that of MLV.
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Objective To investigate the topographic distributions of dopamine transporter (DAT),dopamine D2 receptor and glucose in Parkinson's disease (PD) and multiple system atrophy (MSA) using positron emission tomography/computed tomography (PET/CT) scanning and statistical parametric mapping (SPM) analysis.Methods Seventy subjects (39 PD patients,15 MSA patients and 16 normal controls) who came from People's Liberation Army General Hospital from September 2013 to November 2015 underwent DAT,D2 receptor and glucose brain PET/CT scans using 11 C-methyl-N-2-β-carbomethoxy-3-β-(4-fluorophenyl) tropane (11C-β-CFT),11C-raclopride and 18F-fluorodeoxyglucose (18 F-FDG) as radiotracers,respectively.The uptake patterns were analyzed using SPM software.Results Striatal DAT binding decreased in the putamen in PD patients compared with controls (Z =5.21-5.77,P =0.002-0.016).D2 receptor showed no significant differences.However,glucose uptake decreased in cingulate gyrus(Z =4.51-4.67,P =0.010-0.017).For MSA patients,both DAT and D2 receptor binding decreased in the putamen(Z =2.13-3.42,P =0.000-0.016).Glucose uptake decreased in the bilateral putamen,cerebellum and part of frontal temporal lobes (Z =1.86-3.75,P =0.000-0.032).Conclusion Multiple modalities PET/CT scans using the ligands 11 C-β-CFT,11C-raclopride,and 18F-FDG are valuable in diagnosis of MSA and differential diagnosis of MSA from PD.
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To assure the quality and safety of nuclear medicine imaging,quality control for the imaging equipment is essential.Quality control consists of a series of special tests for assurance and adjustment of equipment accuracy according to specific standards.The development and status of quality control and the standards for nuclear medicine imaging equipment are investigated and reviewed in this study.The results show that the quality control and feasibility of the standards are both in need of improvement in China.
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Objective To investigate the optimal workflow and protocol for integrated PET/MR by comparison with PET/CT.Methods A total of 228 patients were enrolled in this study for PET/CT and PET/MR evaluation on the same day.Six PET/MR protocols with different MR sequences but the same PET acquisition protocol were investigated and the optimal protocol was identified based on image quality,acquisition time and diagnostic performance.Results PET/MR workflow was similar to PET/CT,however,some special issues needed to be considered for PET/MR.Among the 6 protocols,protocol No.6 outperformed others for body and head regions.Types of artifacts were found more often in PET/MR than in PET/CT.Conclusions By optimizing the protocol,PET/MR could achieve almost the same diagnostic performance as PET/CT.However,the issues of long acquisition time and artifacts on PET/MR need to be further improved.
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Objective To simulate the metabolic distribution process of 18F 2-fluoro-2-deoxy-D-glucose(FDG) in human body and to visualize this distribution process through 3D images with high resolution and high quality. Methods The model parameters of FDG metabolism in tissues were estimated through clinical experiments, and the curves which represent the FDG metabolic process in tissues were calculated using the model parameters and blood input function. This FDG distribution process in human body was visualized basing on the high-resolution anatomical structure. Results The simulation and visualization results directly and clearly displayed the FDG metabolic distribution process after injection to human body. The properties of the FDG distribution process represented by our simulation were consistent with that represented by clinical experiment. Conclusion The method presented in this study is effective to simulate and visualize human functional information of metabolism, and it may provide a useful tool for education and research on nuclear imaging.
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<p><b>BACKGROUND</b>To evaluate the diagnostic significance of FDG PET in preoperative mediastinal lymph node staging for NSCLC.</p><p><b>METHODS</b>Whole-body FDG PET imaging was performed in 70 patients with NSCLC. All patients received thoracic CT examination 2 weeks before PET scan or 1 week after PET scan, and then were given thoracotomy with hilar and mediastinal lymph nodes dissection. After intravenous administration of 18F-FDG (150μCi/kg), PET scan was performed in 3-7 bed positions with 2D acquisition and OSEM reconstruction. For quantitative evaluation, a region of interest (ROI) was placed over the mediastinal lymph node which had abnormal uptake of radiation activity, then the standardized uptake value (SUV) were calculated. If SUV≥2.5 or uptake activity was higher than the blood pool of mediastinal on the basis of visual inspection, it was considered to be positive.</p><p><b>RESULTS</b>The sensitivity, specificity and accuracy of PET were 100%, 93% and 94%, respectively. The positive lymph nodes diagnosed by PET correctly corresponded to pathological results. PET changed the clinical staging of 12 patients. The sensitivity, specificity and accuracy of CT were 70%, 77% and 76%, respectively.</p><p><b>CONCLUSIONS</b>PET is an effective modality for accurate mediastinal lymph node staging in patients with NSCLC. It is valuable for determining clinical treatment.</p>
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Objective To give a dose reference to the researcher who study prevention of restenosis using endovascular brachytherapy Methods The dose distributions around a 3 mm diam by 20 mm long balloon filled with 90 Y , 32 P and 186 Re separately have been calculated by a computer program based on a dose point kernel Results The peak value of the absorbed dose is found inside the balloon, the inflexion of the dose curve at the endothelial surface of the vessel In the vessel tissue the dose decreases with distance in an approximately exponential manner The lower the nuclide energy is, the faster the dose falls with distance, and the longer the region of uniform dose distribution along vessel wall is The dose rate at the surface of the vessel wall is approximately 74, 71, and 45 mGy/min per mCi/ml, with the dose rate decreasing to 53%, 48% and 28% at 0 5 mm for 90 Y , 32 P and 186 Re separately Conclusion The fast falling of the dose in an approximately exponential manner in the vessel tissue makes for focusing ? radionuclide energy to the vessel wall target and reducing the injury of the normal tissue around the vessel, and especially 186 Re with lower energy has a more obvious advantage in this aspect
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It is the first time to lay down a complete and accurate plan for clinical verification protocol of domestic SPECT. The protocol's application to the first domestic BHP6601 SPECT proves its definitive purpose, reliability and completion. The protocol can meet the requirements of the criterions of China and related department, and thus must be beneficial to the clinical verification and popularization of large-scale nuclear medicine image equipment.