A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method wit...A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method with scattering angle correction(CSS-BP-SC) can quickly perform the back-projection process of the Compton cone and can be used to precompute the list-mode maximum likelihood expectation maximization(LM-MLEM). A dedicated parallel architecture was designed for the graphics processing unit acceleration of the back-projection and iteration stage of the CSS-BP-SC-based LM-MLEM. The imaging results of the two-point source Monte Carlo(MC) simulation demonstrate that by analyzing the full width at half maximum along the three coordinate axes, the CSS-BP-SC-based LM-MLEM can obtain imaging results comparable to those of the traditional reconstruction algorithm, that is, the simple back-projection-based LM-MLEM. The imaging results of the mouse phantom MC simulation and experiment demonstrate that the reconstruction results obtained by the proposed method sufficiently coincide with the set radioactivity distribution, and the speed increased by more than 664 times compared to the traditional reconstruction algorithm in the mouse phantom experiment. The proposed method will further advance the imaging applications of Compton cameras.展开更多
Purpose To develop a multi-radionuclide imaging system with a flexible and compact structure that has a potential for breast and other applications,and to evaluate its performances under both positron emission tomogra...Purpose To develop a multi-radionuclide imaging system with a flexible and compact structure that has a potential for breast and other applications,and to evaluate its performances under both positron emission tomography and single photon emission imaging conditions.Methods The plane detector was composed of 5×6 blocks with an effective detection area of 168.6 mm×202.4 mm.Each block consisted of a 16×16 LYSO array.The pixel size is 1.9 mm×1.9 mm×15 mm.An 8×8 silicon photomultiplier(SiPM)array with SensL’s C-30035 sensors was coupled to the LYSO array,separated by a 1.5-mm-thick glass.To minimize the influence of temperature on the detector,the active part of the front-end electronics was kept away from SiPMs.Self-designed data acquisition system and reconstruction software were utilized to evaluate the performances of the whole system.Results All the blocks had excellent pixels identification.An average energy resolution of 11.39%for 511 keV and 21.37%for 140 keV was obtained.In the PET mode,the best spatial resolution was better than 2 mm and the system sensitivity reached up to 11.05%at 60 mm distance.In the single photon emission imaging mode,a spatial resolution better than 3 mm was obtained.Conclusion The results indicated that the system has a good overall performance and can be used in breast imaging and other general PET applications.It also has the potential to be used for single photon emission imaging.In pursuit of a better spatial resolution of cross-plane,PSF and DOI technology will be developed in the next work.For specific applications,further improvement of the detector system such as performance evaluation with phantoms will be carried out.展开更多
Objective: To investigate the role and clinical value of radionuclide imaging in hepatic impact injuries in rabbits. Methods: Rabbits were experimentally impacted on the liver with BIM IV bio impact machine. Liver ima...Objective: To investigate the role and clinical value of radionuclide imaging in hepatic impact injuries in rabbits. Methods: Rabbits were experimentally impacted on the liver with BIM IV bio impact machine. Liver imaging was performed with 99m Tc labeled sodium phytate. Liver blood pool imaging was performed with 99m Tc stannous pyrophosphate labeled red blood cells. The results of radionuclide imaging were compared with the anatomic results. Results: There was significant difference between the images of the injured liver and the control. Radio diminution and defect were shown in the injured liver areas. Various sorts of abnormal radioactivity distribution were observed with hepatic blood pool imaging. The results of the liver imaging and liver blood pool imaging were accorded with the results of the anatomic findings. Conclusions: Radionuclide imaging may well display the changes of hepatocellular structures and functions after injury, which is valuable in locating the concrete injured position and differentiating the injured degrees of liver.展开更多
Of 628 patients with extra-osseous malignancies diagnosed by surgery and/or pathology, 207 (33.0%) were identified as having skeletal metastasis by bone imaging. There was statistical significant difference in the inc...Of 628 patients with extra-osseous malignancies diagnosed by surgery and/or pathology, 207 (33.0%) were identified as having skeletal metastasis by bone imaging. There was statistical significant difference in the incidence of metastasis in different malignancies (P<0.02). The metastatic rates of nasopharyn-geal, lung, prostate and breast cancers were higher than gastrointestinal, kidney, and other malignancies. There was significant differences in the different sites of skeletal metastasis (P<0.01). They were thorax, spine, pelvis, limbs and skull in order of incidence. Solitary metastatic rate was 15.9%. Biopsy is advised for patients suspected to have metastatic disease but with only one single 'hot spot' in skeletal imaging, particularly in the rib.展开更多
Lymphoscintigraphy is a nuclear medicine procedure that uses a small quantity of radioactive particles for visualizing the lymphatic system.Traditionally,the radiotracer was injected subcutaneously,but the quality of ...Lymphoscintigraphy is a nuclear medicine procedure that uses a small quantity of radioactive particles for visualizing the lymphatic system.Traditionally,the radiotracer was injected subcutaneously,but the quality of lymphatic path imaging was scarce due to high background.Intradermal radiotracer injection is considered the modern-day intralymphatic injection.We propose rest/stress intradermal lymphoscintigraphy for the diagnosis,staging and surgical planning of lymphedema.Major and minor findings were described in primary and secondary lymphedema.Based on the in-depth information of the lymphatic pathways,physiotherapists and microsurgeons can obtain important functional information in patients’selection to treat with physical treatments and/or undergo microsurgery.展开更多
Objective To evaluate and compare the ability to detect tumor by bis (N-ethoxy-N-ethyl dithiocarbamato) nitrido99mTc(V) [99mTcN(NOEt)2] and99mTc hexakis-2- methoxyisobutyl isonitrile [99mTc-MIBI]. Methods 99mTcN(NOE...Objective To evaluate and compare the ability to detect tumor by bis (N-ethoxy-N-ethyl dithiocarbamato) nitrido99mTc(V) [99mTcN(NOEt)2] and99mTc hexakis-2- methoxyisobutyl isonitrile [99mTc-MIBI]. Methods 99mTcN(NOEt)2 was prepared and quality control was performed using ascending thin-layer chromatography. Four mice bearing Ehrich ascites tumor cells underwent whole body planar imaging at 30 min, 2 h and 4 h after injection of99mTc-MIBI or99mTcN(NOEt)2. ROIs were drawn around the tumor, head, chest, and contralateral limbs in whole body planar images, and ratios of radioactivity in tumor in head (T/H), chest (T/C), and contralateral limbs (T/L) were calculated. The mice of99mTcN (NOEt)2 group were killed, then blood was collected, and the tumor and organs were excised, weighed and the radioactivity was measured. Results 99mTcN(NOEt)2 was stable after 4h at the room temperature.99mTcN(NOEt)2 was delivered to the tumor selectively and efficiently.99mTcN(NOEt)2 was found to provide excellent tumor-to-nontumor contrast for all the tissue except the abdomen. The T/L ratios increased to their maximums (4.87) at 2 h after injection. There was significant difference between the99mTcN(NOEt)2 imaging group and99mTc-MIBI imaging group. In vitro the radioactivity ratios per unit weight of tumor to blood, muscle, skeleton, lung, heart, and spleen were much higher than those of tumor to liver, instestine. Conclusion In mice bearing Ehrich ascites tumor,99mTcN(NOEt)2 exhibits a set of features essential for a good tracer for tumor imaging, including a rapid washout from blood, high uptake rate in tumor tissue, prolonged retention and high tumor-to-nontumor uptake ratio. The imaging quality of99mTcN(NOEt)2 was superior to that of99mTc-MIBI. These features indicate that99mTcN(NOEt)2 may be a better tracer to detect tumor than99mTc-MIBI. Key words tumor - radionuclide imaging - NOEt - MIBI展开更多
Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bon...Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bone and describes the available imaging methods to diagnose bone metastasis and monitor response to treatment. Among the various imaging modalities currently available for imaging skeletal metastasis, hybrid techniques whichfuse morphological and functional data are the most sensitive and specific, and positron emission tomography(PET)/computed tomography and PET/magnetic resonance imaging will almost certainly continue to evolve and become increasingly important in this regard.展开更多
The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A,...The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A, stannous tartrate solution was used. ^99mTc-Ap4A was purified on a Sephadex G-25 column. The radiochemistry purities of ^99mTc-Ap4A were 85% to 91%. Biodistribution study revealed ^99mTc-Ap4A cleared from blood rapidly. Thirty min after ^99mTc-Ap4A administrated on NZW atherosclerotic rabbits, lesion to blood （target/blood, T/B） ratio was 3. 17 ±1.27, and lesions to normal （target/non-target, T/NT） ratio was 5.23 ±1.87. Shadows of atherosclerotic plaques were clearly visible on radioautographic film. Aortas with atherosclerotic plaques also could be seen on ex vivo gamma camera images. Atherosclerotic abdominal aortas were clearly visible on in vivo images 15 min to 3 h after ^99mTc-Ap4A administration. ^99mTc-labeled Ap4A can be used for rapid noninvasive detection of experimental atherosclerotic plaque.展开更多
OBJECTIVE To explore the method of preparation of 99m↑Tc labeled AntiVEGF McAb 5-FU loaded polylactic acid nanoparticles （99m↑TC-5-FU-Ab-NPs）, and investigate the biological distribution of the nanoparticles in hu...OBJECTIVE To explore the method of preparation of 99m↑Tc labeled AntiVEGF McAb 5-FU loaded polylactic acid nanoparticles （99m↑TC-5-FU-Ab-NPs）, and investigate the biological distribution of the nanoparticles in human gastric carcinoma xenografts. METHODS Anti-VEGF monoclonal antibodyes （MCAB）in 5-FU-Ab-NPs were labeled with 99m↑Tc using a modified Schwarz method. After isolation of the 99m↑TC-5-FU-Ab-NPs using a Sephadex G-250 column, the labeling percentage and radiochemical purity were determined using paper chromatography. The immunocempetence of the 99m↑TC-5-FU-Ab-NPs as tumor markers was determined using ELISA and immunohistochemistry. 99m↑TC-5-FU-Ab-NPs （experimental group）, 99m↑Tc-labelled murine multiclonal IgG loaded polylactic acid and nanoparticles （control group） were injected via the tail vein into SCID mice bearing human gastric carcinoma. A radio-immunity ECT image was developed at 2 and 6 h after the injection. Following the ECT imaging, the mice were sacrificed, their tissue and tumor radioactivity distribution determined, and percentage of the injected-dose per gram （%ID/g） and tumor/ nontumor （T/NT） ratio calculated. High performance liquid chromatography （HPLC） was used to determine the 5-FU concentration in the tumor tissue and blood in the mice of both groups. RESULTS The percentage of 99m↑TC-5-FU-Ab-NPs labeling was 90%-95%. There was no obvious decrease in the antibody activity before and after labeling. The radio-immuno-imaging （RII） showed that the tumor image had developed 2 h after injection of the 99m↑TC-5-FU-Ab-NPs, and with time it was clearer at the 6th hour following the injection. The %lD/g of the tumor tissue at both 2 h and 6 h after the injection was significantly higher compared to the control group. The tumor %lD/g and the tumor to blood activity ratio （TB） of the experimental group at 6 h following the injection increased compared to that at 2 h, and at the same time, 5-FU concentration in the tumor of the experimental group continuously increased over time, and showed a significant difference compared to the 5-FU concentration in the tumor of the control group. CONCLUSION The 99m↑TC-5-FU-Ab-NPs prepared in this study are adequate to meet the demands of the RII, and the immune targeting ability of the anti-VEGF MCAB is reliable. Six hours after injection, the 99m↑TC-5-FU-Ab-NPs showed a relatively high specific concentration shadow in the human gastric carcinoma xenografts.展开更多
The aim of this study was to detect coronary artery disease using 99m Tc MIBI myocardial perfusion imaging in patients with valvular disease. [WT5”BX]Methods.[WT5”BZ] Thirty patients with valvular disease confirmed ...The aim of this study was to detect coronary artery disease using 99m Tc MIBI myocardial perfusion imaging in patients with valvular disease. [WT5”BX]Methods.[WT5”BZ] Thirty patients with valvular disease confirmed by echocardiography underwent 99m Tc MIBI myocardial perfusion imaging using multiSPECT 1h after stress test (exercise, dipyridamole or dobutamine test) and were performed coronary angiography within 1 month before valvular operation. [WT5”BX]Results.[WT5”BZ]For 29 out of the 30 patients, the results of 99m Tc MIBI myocardial perfusion imaging were similar with those of coronary angiography, the concordance rate was 96 7% and the negative predictability was 100%. [WT5”BX]Conclusion.[WT5”BZ] 99m Tc MIBI myocardial perfusion imaging is a reliable non invasive method for detecting coronary artery disease in patients with valvular disease and so as to draw up suitable operation programs for them.展开更多
BACKGROUND Hepatobiliary scintigraphy(HBS)is a useful diagnostic imaging technique that uses radiotracers to evaluate the function of the gallbladder(GB)and biliary system.In segmented GB,some HBS images reveal a disc...BACKGROUND Hepatobiliary scintigraphy(HBS)is a useful diagnostic imaging technique that uses radiotracers to evaluate the function of the gallbladder(GB)and biliary system.In segmented GB,some HBS images reveal a discordant GB boundary as compared to anatomical images.AIM To evaluate the characteristics of HBS in segmented GB and determine the clinical relevance according to HBS characteristics.METHODS A total of 268 patients with chronic cholecystitis,gallstones,or biliary colic symptoms who underwent HBS between 2011 and 2020 were enrolled.Segmented GB was defined as segmental luminal narrowing of the GB body on computed tomography(CT)or magnetic resonance(MR)images,and HBS was examined 1 mo before or after CT or MR.Segmented GB was classified into 3 types based on the filling and emptying patterns of the proximal and distal segments according to the characteristics of HBS images,and GB ejection fraction(GBEF)was identified:Type 1 was defined as a normal filling and emptying pattern;Type 2 was defined as an emptying defect on the distal segment;and Type 3 was defined as a filling defect in the distal segment.RESULTS Segmented GB accounted for 63 cases(23.5%),including 36 patients(57.1%)with Type 1,18 patients(28.6%)with Type 2,and 9 patients(14.3%)with Type 3 emptying pattern.Thus,approximately 43%of HBS images showed a discordant pattern as compared to anatomical imaging of segmented GB.Although there were no significant differences in clinical symptoms,rate of cholecystectomy,or pathological findings based on the type,most gallstones occurred in the distal segment.Reported GBEF was 62.50%±24.79%for Type 1,75.89%±17.21%for Type 2,and 88.56%±7.20%for Type 3.Type 1 showed no difference in reported GBEF compared to the non-segmented GB group(62.50%±24.79%vs 67.40%±21.78%).In contrast,the reported GBEF was higher in Types 2 and 3 with defective emptying and filling when compared to Type 1(80.11%±15.70%vs 62.57%±24.79%;P=0.001).CONCLUSION In segmented GB,discordance in the filling patterns detected by HBS and anatomical imaging could lead to misinterpretation of GBEF.For this reason,clinicians should be cautious when interpreting HBS results in patients with segmented GB.展开更多
BACKGROUND Hepatopulmonary syndrome (HPS) is an arterial oxygenation defect induced by intrapulmonary vascular dilatation (IPVD) in the setting of liver disease and/or portal hypertension.This syndrome occurs most oft...BACKGROUND Hepatopulmonary syndrome (HPS) is an arterial oxygenation defect induced by intrapulmonary vascular dilatation (IPVD) in the setting of liver disease and/or portal hypertension.This syndrome occurs most often in cirrhotic patients(4%-32%) and has been shown to be detrimental to functional status,quality of life,and survival.The diagnosis of HPS in the setting of liver disease and/or portal hypertension requires the demonstration of IPVD (i.e.,diffuse or localized abnormally dilated pulmonary capillaries and pulmonary and pleural arteriovenous communications) and arterial oxygenation defects,preferably by contrast-enhanced echocardiography and measurement of the alveolar-arterial oxygen gradient,respectively.AIM To compare brain and whole-body uptake of technetium for diagnosing HPS.METHODS Sixty-nine patients with chronic liver disease and/or portal hypertension were prospectively included.Brain uptake and whole-body uptake were calculated using the geometric mean of technetium counts in the brain and lungs and in the entire body and lungs,respectively.RESULTS Thirty-two (46%) patients had IPVD as detected by contrast-enhancedechocardiography.The demographics and clinical characteristics of the patients with and without IPVD were not significantly different with the exception of the creatinine level (0.71±0.18 mg/dL vs 0.83±0.23 mg/dL;P=0.041),alveolararterial oxygen gradient (23.2±13.3 mmHg vs 16.4±14.1 mmHg;P=0.043),and arterial partial pressure of oxygen (81.0±12.1 mmHg vs 90.1±12.8 mmHg;P=0.004).Whole-body uptake was significantly higher in patients with IPVD than in patients without IPVD (48.0%±6.1%vs 40.1%±8.1%;P=0.001).The area under the curve of whole-body uptake for detecting IPVD was significantly higher than that of brain uptake (0.75 vs 0.54;P=0.025).The optimal cut-off values of brain uptake and whole-body uptake for detecting IPVD were 5.7%and 42.5%,respectively,based on Youden’s index.The sensitivity,specificity,and accuracy of brain uptake> 5.7%and whole-body uptake> 42.5%for detecting IPVD were23%,89%,and 59%and 100%,52%,and 74%,respectively.CONCLUSION Whole-body uptake is superior to brain uptake for diagnosing HPS.展开更多
Hip prosthetic loosening is often difficult to detect at an early stage,and there has been uncertainty for a long time as to when the loosening occurs and thus to the basic causes.By comparing different diagnostic met...Hip prosthetic loosening is often difficult to detect at an early stage,and there has been uncertainty for a long time as to when the loosening occurs and thus to the basic causes.By comparing different diagnostic methods,we found that loosening is best defined as prosthetic migration and measured by radiostereometric analysis.Convincing evidence indicates that poor interlock,poor bone quality,and resorption of a necrotic bone bed may initiate loosening during or shortly after surgery;this forms the basis of the theory of early loosening.Biomechanical factors do affect the subsequent progression of loosening,which may increase subclinically during a long period of time.Eventually,the loosening may be detected on standard radiographs and may be interpreted as late loosening but should to be interpreted as late detection of loosening.The theory of early loosening explains the rapid early migration,the development of periprosthetic osteolysis and granulomas,the causality between wear and loosening,and largely the epidemiology of clinical failure of hip prostheses.Aspects discussed are definition of loosening,the pattern of early migration,the choice of migration threshold,the current understanding of loosening,a less exothermic bone cement,cemented taper-slip stems,a new exciting computed tomography-based technique for simpler implant migration studies,and research suggestions.展开更多
Objective： To discuss if the sentinel lymph node （SLN） biopsy is able to reflect the status of the axillary lymph node and the application of this technic in clinic. Methods： Using^ 99mTc-signed dextran, SLN-biop...Objective： To discuss if the sentinel lymph node （SLN） biopsy is able to reflect the status of the axillary lymph node and the application of this technic in clinic. Methods： Using^ 99mTc-signed dextran, SLN-biopsy （SLNB） was carried out in 182 cases with breast cancer during May 1999 to September 2006. During the operation, y-detector was used for orientation. After the SLNB, a modified radical mastectomy or breast conserving surgery were carried out to the patients, then a particular separate pathological examination of the SLN was made. Results： 178 cases of SLNB were carried out successfully, and the success rate was 97.8%, the out-checked SLN of each case ranged from 1 to 4, with an average of 2.5. All SLN was located at the first level of axilla, sensitivity of the SLN B was 93.4%, specificity was 100%, false negative rate was 6.6%, false positive rate was 0, accuracy was 97.8%, positive predictive value was 100.0%, negative predictive value was 96.7%, and Youden＇s index was 0.934. Immunohistochemical examination was carried out in 59 cases of SLN, and 14 cases showed the existences of micro-metastasis, however, metastasis had not been found in non-SLN of these cases. Conclusion： SLN is able to reflect the metastasis of the axillary lymph node, and this can suggest the necessity of the axillary dissection in clinic. The SLNB using the isotope-tracer technic is simple and accurate.展开更多
Objective： The aim of this study was to compare the effect of 131I therapy of different clinical stages in postopera- tive patients with papillary thyroid carcinoma （PTC）. Methods： Eighty-seven PTC patients after ...Objective： The aim of this study was to compare the effect of 131I therapy of different clinical stages in postopera- tive patients with papillary thyroid carcinoma （PTC）. Methods： Eighty-seven PTC patients after surgery ablated with high doses of 131I from 2004 to 2010 were retrospectively reviewed. The efficacy of 131I therapy was assessed by three diagnostics that serum thyroglobulin （Tg） was normal or significantly reduced, 131I whole body scan （131I-WBS） was negative or the metas- tases shrank or the number of them decreased and new metastases was not found in cervical ultrasound examination. The x2 test was used to analyze 3 factors which might affect the therapeutic efficacy of 131I in patients of different clinical period, including different surgical ways （total or subtotal thyroidectomy along with half or double sides neck lymph node dissection）, age （〈 45 years and 〉 45 years） and ablative 131I dose. Results： Of 87 patients, the effective rate of 46 patients I stage was 89.13% （41）; the effective rate of 22 cases III stage was 77.27% （17）; the effective rate of 19 cases IV stage was 36.84% （7）. The corresponding intra-groups statistical difference of 3 stages was significant by x2 test （x2 = 1.72, 19.03, 6.87; P 〉 0.25, P 〈 0.005, P 〈 0.01）. The effective rate was 91.67% （44） in 48 cases undergoing total thyroidectomy; the effective rate was 53.85% （21） in 39 patients undergoing subtotal thyroidectomy. There was a significant difference between the two groups above by x2 test （x2 = 16.291; P 〈 0.005）. Conclusion： The efficacy of 131I ablation of stage I and stage III in postoperative PTC patients was almost alike, while the efficacy of stage IV descended markedly. The results was mainly determined by residual thyroid tissue size because of different surgical modus.展开更多
Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,...Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,imaging methods that are currently used for clinical diagnosis have drawbacks,such as low sensitivity and accuracy.Contrast agents are often used in diagnostic imaging to address these drawbacks.Nanocontrast agents have attracted considerable attention in recent years due to their unique physicochemical characteristics.Among these agents,inorganic nanoprobes have been substantially developed through improvements in synthesis techniques and pairings with other organic molecules.This paper mainly summarizes the specific applications of inorganic nanoprobes in the magnetic resonance imaging,fluorescence imaging,radionuclide imaging,and bimodal/multimodal imaging of breast cancer.展开更多
Objective.To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection(TCPC)of different types,and to provide the selection of the best type.Methods. Thirty-two consecutive survival ...Objective.To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection(TCPC)of different types,and to provide the selection of the best type.Methods. Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs,analyses of the distribution of blood flow from superior venous cava(SVC) and inferior venous cava(IVC)and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Results. GroupⅠ:The flow ratio of the IVC to left lung was greater than that to the right lung,P≤0.01;the flow ratio of the SVC to right lung was greater than that to the left lung,P≤0.01;and the whole pulmonary blood flow went dominantly to the left lung,P≤0.05,which is not in line with physiological distribution. GroupⅡ:the flows from the SVC and IVC were mixed in the middle of the junction and ran evenly into the right and left lungs,the whole pulmonary blood flow went to both lungs,P≥0.05. Group Ⅲ:the flow ratio of the SVC to both lungs were the same,P≥0.05,and major part from IVC went to the right lung,P≤0.01;the pulmonary blood flow go dominantly to the right lung,P≤0.05,which is in accord with physiological distribution. Group Ⅳ:the flows from the right SVC went to right lung by 100%,P≤0.01,and that from the left SVC went to left lung by 100% too,P≤0.01;the flows from IVC went dominantly to the left lung,with little part to the right lung ,P≤0.05.Conclusions. Different types of TCPC can result in different pulmonary blood distributions. The best flow distribution between the left and right lungs can be obtained by an offset of the IVC anastomosis toward the RPA with widening anastomosis for the patients without persist left superior venous cava(PLSVC).展开更多
Nanogels （NGs） as soft nanosized materials have gained a variety of interests in biomedical fields. The versatile NG scaffolds with 3-dimensional spherical shape, high loading efficiency, tunable surface functionali...Nanogels （NGs） as soft nanosized materials have gained a variety of interests in biomedical fields. The versatile NG scaffolds with 3-dimensional spherical shape, high loading efficiency, tunable surface functionalization, and excellent biocompatibility afford their uses as carrier to load mono- or multi-mode molecular imaging contrast agents （CAs）. This review summarizes the synthesis routes and applications of NGs as CAs for molecular imaging applications including magnetic resonance （MR）, computed tomography （CT）, radionuclide, optical, and dual/mul- ti-modality imaging.展开更多
Background The YIGSR is a pentapeptide, from the laminin-1 of the β1 chain, which can mediate cell adhesion and bind the 67 kD laminin receptor. The purpose is to evaluate the usefulness of 99m Tc-YIGSR, a novel ...Background The YIGSR is a pentapeptide, from the laminin-1 of the β1 chain, which can mediate cell adhesion and bind the 67 kD laminin receptor. The purpose is to evaluate the usefulness of 99m Tc-YIGSR, a novel tumour radiotracer, in the receptor imaging of Ehrlich ascites tumour. Methods Using S-Acetly-NH_3-MAG_3 as chelate, YIGSR, a pentapeptide from laminin, was tagged with 99m Tc. 99m Tc-YIGSR was detected in the tumour group bearing Ehrlich ascites tumour and blocked group. Tumour, normal, inflammatory and blocked groups were imaged. Results Through reverse phase Sep-Pak C_ 18 chromatogram, it was revealed that YIGSR could conjugate with S-Acetly -NH_3-MAG_3, and be radiolabelled at room temperature and neutral pH with a radiolabelling yield of 62%, and of 4% without chelate. 99m Tc-YIGSR was rapidly cleared from kidney, then liver. The imaging findings showed tumour tissue accumulated initial radioactivity at fifteen minutes after injection in the tumour group, and the uptake increased to peak at three hours with a tumour/muscle ratio (T/M) of 11.36, then cleared slowly to a T/M of 7.50 at eight hours. The tumour uptake of radiotracer in blocked group was significantly lower with T/M of 4.61 at three hours and 0.89 at eight hours. The T/M was only 3.72 at three hours and 1.29 at eight hours after injection in inflammatory group. Compared with inflammatory group and control obstructive group, the ratio of T/M in tumour group was significantly different ( P <0.001). Conclusions Using S-Acetly-NH_3-MAG_3, we radiolabelled YIGSR with 99m Tc. 99m Tc-YIGSR possesses many merits of tumour imaging: rapid visualization, high sensitivity and specificity, and satisfactory target/nontarget ratio. Our data suggest 99m Tc-YIGSR is a promising tumour radiotracer.展开更多
基金supported by the National Natural Science Foundation of China (No. 12220101005)Natural Science Foundation of Jiangsu Province (No. BK20220132)+2 种基金Primary Research and Development Plan of Jiangsu Province (No. BE2019002-3)Fundamental Research Funds for Central Universities (No. NG2022004)the Foundation of the Graduate Innovation Center in NUAA (No. xcxjh20210613)。
文摘A novel and fast three-dimensional reconstruction method for a Compton camera and its performance in radionuclide imaging is proposed and analyzed in this study. The conical surface sampling back-projection method with scattering angle correction(CSS-BP-SC) can quickly perform the back-projection process of the Compton cone and can be used to precompute the list-mode maximum likelihood expectation maximization(LM-MLEM). A dedicated parallel architecture was designed for the graphics processing unit acceleration of the back-projection and iteration stage of the CSS-BP-SC-based LM-MLEM. The imaging results of the two-point source Monte Carlo(MC) simulation demonstrate that by analyzing the full width at half maximum along the three coordinate axes, the CSS-BP-SC-based LM-MLEM can obtain imaging results comparable to those of the traditional reconstruction algorithm, that is, the simple back-projection-based LM-MLEM. The imaging results of the mouse phantom MC simulation and experiment demonstrate that the reconstruction results obtained by the proposed method sufficiently coincide with the set radioactivity distribution, and the speed increased by more than 664 times compared to the traditional reconstruction algorithm in the mouse phantom experiment. The proposed method will further advance the imaging applications of Compton cameras.
基金the National NaturalScience Foundation of China(Grant Nos.11475206,11675191,and11805215).
文摘Purpose To develop a multi-radionuclide imaging system with a flexible and compact structure that has a potential for breast and other applications,and to evaluate its performances under both positron emission tomography and single photon emission imaging conditions.Methods The plane detector was composed of 5×6 blocks with an effective detection area of 168.6 mm×202.4 mm.Each block consisted of a 16×16 LYSO array.The pixel size is 1.9 mm×1.9 mm×15 mm.An 8×8 silicon photomultiplier(SiPM)array with SensL’s C-30035 sensors was coupled to the LYSO array,separated by a 1.5-mm-thick glass.To minimize the influence of temperature on the detector,the active part of the front-end electronics was kept away from SiPMs.Self-designed data acquisition system and reconstruction software were utilized to evaluate the performances of the whole system.Results All the blocks had excellent pixels identification.An average energy resolution of 11.39%for 511 keV and 21.37%for 140 keV was obtained.In the PET mode,the best spatial resolution was better than 2 mm and the system sensitivity reached up to 11.05%at 60 mm distance.In the single photon emission imaging mode,a spatial resolution better than 3 mm was obtained.Conclusion The results indicated that the system has a good overall performance and can be used in breast imaging and other general PET applications.It also has the potential to be used for single photon emission imaging.In pursuit of a better spatial resolution of cross-plane,PSF and DOI technology will be developed in the next work.For specific applications,further improvement of the detector system such as performance evaluation with phantoms will be carried out.
文摘Objective: To investigate the role and clinical value of radionuclide imaging in hepatic impact injuries in rabbits. Methods: Rabbits were experimentally impacted on the liver with BIM IV bio impact machine. Liver imaging was performed with 99m Tc labeled sodium phytate. Liver blood pool imaging was performed with 99m Tc stannous pyrophosphate labeled red blood cells. The results of radionuclide imaging were compared with the anatomic results. Results: There was significant difference between the images of the injured liver and the control. Radio diminution and defect were shown in the injured liver areas. Various sorts of abnormal radioactivity distribution were observed with hepatic blood pool imaging. The results of the liver imaging and liver blood pool imaging were accorded with the results of the anatomic findings. Conclusions: Radionuclide imaging may well display the changes of hepatocellular structures and functions after injury, which is valuable in locating the concrete injured position and differentiating the injured degrees of liver.
文摘Of 628 patients with extra-osseous malignancies diagnosed by surgery and/or pathology, 207 (33.0%) were identified as having skeletal metastasis by bone imaging. There was statistical significant difference in the incidence of metastasis in different malignancies (P<0.02). The metastatic rates of nasopharyn-geal, lung, prostate and breast cancers were higher than gastrointestinal, kidney, and other malignancies. There was significant differences in the different sites of skeletal metastasis (P<0.01). They were thorax, spine, pelvis, limbs and skull in order of incidence. Solitary metastatic rate was 15.9%. Biopsy is advised for patients suspected to have metastatic disease but with only one single 'hot spot' in skeletal imaging, particularly in the rib.
文摘Lymphoscintigraphy is a nuclear medicine procedure that uses a small quantity of radioactive particles for visualizing the lymphatic system.Traditionally,the radiotracer was injected subcutaneously,but the quality of lymphatic path imaging was scarce due to high background.Intradermal radiotracer injection is considered the modern-day intralymphatic injection.We propose rest/stress intradermal lymphoscintigraphy for the diagnosis,staging and surgical planning of lymphedema.Major and minor findings were described in primary and secondary lymphedema.Based on the in-depth information of the lymphatic pathways,physiotherapists and microsurgeons can obtain important functional information in patients’selection to treat with physical treatments and/or undergo microsurgery.
文摘Objective To evaluate and compare the ability to detect tumor by bis (N-ethoxy-N-ethyl dithiocarbamato) nitrido99mTc(V) [99mTcN(NOEt)2] and99mTc hexakis-2- methoxyisobutyl isonitrile [99mTc-MIBI]. Methods 99mTcN(NOEt)2 was prepared and quality control was performed using ascending thin-layer chromatography. Four mice bearing Ehrich ascites tumor cells underwent whole body planar imaging at 30 min, 2 h and 4 h after injection of99mTc-MIBI or99mTcN(NOEt)2. ROIs were drawn around the tumor, head, chest, and contralateral limbs in whole body planar images, and ratios of radioactivity in tumor in head (T/H), chest (T/C), and contralateral limbs (T/L) were calculated. The mice of99mTcN (NOEt)2 group were killed, then blood was collected, and the tumor and organs were excised, weighed and the radioactivity was measured. Results 99mTcN(NOEt)2 was stable after 4h at the room temperature.99mTcN(NOEt)2 was delivered to the tumor selectively and efficiently.99mTcN(NOEt)2 was found to provide excellent tumor-to-nontumor contrast for all the tissue except the abdomen. The T/L ratios increased to their maximums (4.87) at 2 h after injection. There was significant difference between the99mTcN(NOEt)2 imaging group and99mTc-MIBI imaging group. In vitro the radioactivity ratios per unit weight of tumor to blood, muscle, skeleton, lung, heart, and spleen were much higher than those of tumor to liver, instestine. Conclusion In mice bearing Ehrich ascites tumor,99mTcN(NOEt)2 exhibits a set of features essential for a good tracer for tumor imaging, including a rapid washout from blood, high uptake rate in tumor tissue, prolonged retention and high tumor-to-nontumor uptake ratio. The imaging quality of99mTcN(NOEt)2 was superior to that of99mTc-MIBI. These features indicate that99mTcN(NOEt)2 may be a better tracer to detect tumor than99mTc-MIBI. Key words tumor - radionuclide imaging - NOEt - MIBI
文摘Early detection of skeletal metastasis is critical for accurate staging and optimal treatment. This paper briefly reviews our current understanding of the biological mechanisms through which tumours metastasise to bone and describes the available imaging methods to diagnose bone metastasis and monitor response to treatment. Among the various imaging modalities currently available for imaging skeletal metastasis, hybrid techniques whichfuse morphological and functional data are the most sensitive and specific, and positron emission tomography(PET)/computed tomography and PET/magnetic resonance imaging will almost certainly continue to evolve and become increasingly important in this regard.
文摘The potential of ^99mTc labeled P^1, P^4-di （adenosine-5 ＇ ）-tetraphosphate （Ap4A） for imaging experimental atherosclerotic plaques was evaluated in New Zealand white （NZW） rabbits. To label the ^99mTc to Ap4A, stannous tartrate solution was used. ^99mTc-Ap4A was purified on a Sephadex G-25 column. The radiochemistry purities of ^99mTc-Ap4A were 85% to 91%. Biodistribution study revealed ^99mTc-Ap4A cleared from blood rapidly. Thirty min after ^99mTc-Ap4A administrated on NZW atherosclerotic rabbits, lesion to blood （target/blood, T/B） ratio was 3. 17 ±1.27, and lesions to normal （target/non-target, T/NT） ratio was 5.23 ±1.87. Shadows of atherosclerotic plaques were clearly visible on radioautographic film. Aortas with atherosclerotic plaques also could be seen on ex vivo gamma camera images. Atherosclerotic abdominal aortas were clearly visible on in vivo images 15 min to 3 h after ^99mTc-Ap4A administration. ^99mTc-labeled Ap4A can be used for rapid noninvasive detection of experimental atherosclerotic plaque.
基金the grants as fol-lows:The Problems-Tackling Program in Sci-ence and Technology of Guangzhou City,Chi-na(No.2003 Z 3-E0381)National Foundationof Natural Science,China(No.30670951)+1 种基金Guangdong Foundation of Natural Science,Guangdong,China(No.06021322)TheProblems-Tackling Program in Science andTechnology of Guangdong Province,China(No.2005 B31211002).
文摘OBJECTIVE To explore the method of preparation of 99m↑Tc labeled AntiVEGF McAb 5-FU loaded polylactic acid nanoparticles （99m↑TC-5-FU-Ab-NPs）, and investigate the biological distribution of the nanoparticles in human gastric carcinoma xenografts. METHODS Anti-VEGF monoclonal antibodyes （MCAB）in 5-FU-Ab-NPs were labeled with 99m↑Tc using a modified Schwarz method. After isolation of the 99m↑TC-5-FU-Ab-NPs using a Sephadex G-250 column, the labeling percentage and radiochemical purity were determined using paper chromatography. The immunocempetence of the 99m↑TC-5-FU-Ab-NPs as tumor markers was determined using ELISA and immunohistochemistry. 99m↑TC-5-FU-Ab-NPs （experimental group）, 99m↑Tc-labelled murine multiclonal IgG loaded polylactic acid and nanoparticles （control group） were injected via the tail vein into SCID mice bearing human gastric carcinoma. A radio-immunity ECT image was developed at 2 and 6 h after the injection. Following the ECT imaging, the mice were sacrificed, their tissue and tumor radioactivity distribution determined, and percentage of the injected-dose per gram （%ID/g） and tumor/ nontumor （T/NT） ratio calculated. High performance liquid chromatography （HPLC） was used to determine the 5-FU concentration in the tumor tissue and blood in the mice of both groups. RESULTS The percentage of 99m↑TC-5-FU-Ab-NPs labeling was 90%-95%. There was no obvious decrease in the antibody activity before and after labeling. The radio-immuno-imaging （RII） showed that the tumor image had developed 2 h after injection of the 99m↑TC-5-FU-Ab-NPs, and with time it was clearer at the 6th hour following the injection. The %lD/g of the tumor tissue at both 2 h and 6 h after the injection was significantly higher compared to the control group. The tumor %lD/g and the tumor to blood activity ratio （TB） of the experimental group at 6 h following the injection increased compared to that at 2 h, and at the same time, 5-FU concentration in the tumor of the experimental group continuously increased over time, and showed a significant difference compared to the 5-FU concentration in the tumor of the control group. CONCLUSION The 99m↑TC-5-FU-Ab-NPs prepared in this study are adequate to meet the demands of the RII, and the immune targeting ability of the anti-VEGF MCAB is reliable. Six hours after injection, the 99m↑TC-5-FU-Ab-NPs showed a relatively high specific concentration shadow in the human gastric carcinoma xenografts.
文摘The aim of this study was to detect coronary artery disease using 99m Tc MIBI myocardial perfusion imaging in patients with valvular disease. [WT5”BX]Methods.[WT5”BZ] Thirty patients with valvular disease confirmed by echocardiography underwent 99m Tc MIBI myocardial perfusion imaging using multiSPECT 1h after stress test (exercise, dipyridamole or dobutamine test) and were performed coronary angiography within 1 month before valvular operation. [WT5”BX]Results.[WT5”BZ]For 29 out of the 30 patients, the results of 99m Tc MIBI myocardial perfusion imaging were similar with those of coronary angiography, the concordance rate was 96 7% and the negative predictability was 100%. [WT5”BX]Conclusion.[WT5”BZ] 99m Tc MIBI myocardial perfusion imaging is a reliable non invasive method for detecting coronary artery disease in patients with valvular disease and so as to draw up suitable operation programs for them.
基金reviewed and approved by the Jeonbuk National University Hospital Institutional Review Board,No.2021-07-005.
文摘BACKGROUND Hepatobiliary scintigraphy(HBS)is a useful diagnostic imaging technique that uses radiotracers to evaluate the function of the gallbladder(GB)and biliary system.In segmented GB,some HBS images reveal a discordant GB boundary as compared to anatomical images.AIM To evaluate the characteristics of HBS in segmented GB and determine the clinical relevance according to HBS characteristics.METHODS A total of 268 patients with chronic cholecystitis,gallstones,or biliary colic symptoms who underwent HBS between 2011 and 2020 were enrolled.Segmented GB was defined as segmental luminal narrowing of the GB body on computed tomography(CT)or magnetic resonance(MR)images,and HBS was examined 1 mo before or after CT or MR.Segmented GB was classified into 3 types based on the filling and emptying patterns of the proximal and distal segments according to the characteristics of HBS images,and GB ejection fraction(GBEF)was identified:Type 1 was defined as a normal filling and emptying pattern;Type 2 was defined as an emptying defect on the distal segment;and Type 3 was defined as a filling defect in the distal segment.RESULTS Segmented GB accounted for 63 cases(23.5%),including 36 patients(57.1%)with Type 1,18 patients(28.6%)with Type 2,and 9 patients(14.3%)with Type 3 emptying pattern.Thus,approximately 43%of HBS images showed a discordant pattern as compared to anatomical imaging of segmented GB.Although there were no significant differences in clinical symptoms,rate of cholecystectomy,or pathological findings based on the type,most gallstones occurred in the distal segment.Reported GBEF was 62.50%±24.79%for Type 1,75.89%±17.21%for Type 2,and 88.56%±7.20%for Type 3.Type 1 showed no difference in reported GBEF compared to the non-segmented GB group(62.50%±24.79%vs 67.40%±21.78%).In contrast,the reported GBEF was higher in Types 2 and 3 with defective emptying and filling when compared to Type 1(80.11%±15.70%vs 62.57%±24.79%;P=0.001).CONCLUSION In segmented GB,discordance in the filling patterns detected by HBS and anatomical imaging could lead to misinterpretation of GBEF.For this reason,clinicians should be cautious when interpreting HBS results in patients with segmented GB.
基金Supported by National Key R and D Program of China,No.2017YFC0107800CAMS Initiative for Innovative Medicine,No.2016-12M-2-004
文摘BACKGROUND Hepatopulmonary syndrome (HPS) is an arterial oxygenation defect induced by intrapulmonary vascular dilatation (IPVD) in the setting of liver disease and/or portal hypertension.This syndrome occurs most often in cirrhotic patients(4%-32%) and has been shown to be detrimental to functional status,quality of life,and survival.The diagnosis of HPS in the setting of liver disease and/or portal hypertension requires the demonstration of IPVD (i.e.,diffuse or localized abnormally dilated pulmonary capillaries and pulmonary and pleural arteriovenous communications) and arterial oxygenation defects,preferably by contrast-enhanced echocardiography and measurement of the alveolar-arterial oxygen gradient,respectively.AIM To compare brain and whole-body uptake of technetium for diagnosing HPS.METHODS Sixty-nine patients with chronic liver disease and/or portal hypertension were prospectively included.Brain uptake and whole-body uptake were calculated using the geometric mean of technetium counts in the brain and lungs and in the entire body and lungs,respectively.RESULTS Thirty-two (46%) patients had IPVD as detected by contrast-enhancedechocardiography.The demographics and clinical characteristics of the patients with and without IPVD were not significantly different with the exception of the creatinine level (0.71±0.18 mg/dL vs 0.83±0.23 mg/dL;P=0.041),alveolararterial oxygen gradient (23.2±13.3 mmHg vs 16.4±14.1 mmHg;P=0.043),and arterial partial pressure of oxygen (81.0±12.1 mmHg vs 90.1±12.8 mmHg;P=0.004).Whole-body uptake was significantly higher in patients with IPVD than in patients without IPVD (48.0%±6.1%vs 40.1%±8.1%;P=0.001).The area under the curve of whole-body uptake for detecting IPVD was significantly higher than that of brain uptake (0.75 vs 0.54;P=0.025).The optimal cut-off values of brain uptake and whole-body uptake for detecting IPVD were 5.7%and 42.5%,respectively,based on Youden’s index.The sensitivity,specificity,and accuracy of brain uptake> 5.7%and whole-body uptake> 42.5%for detecting IPVD were23%,89%,and 59%and 100%,52%,and 74%,respectively.CONCLUSION Whole-body uptake is superior to brain uptake for diagnosing HPS.
文摘Hip prosthetic loosening is often difficult to detect at an early stage,and there has been uncertainty for a long time as to when the loosening occurs and thus to the basic causes.By comparing different diagnostic methods,we found that loosening is best defined as prosthetic migration and measured by radiostereometric analysis.Convincing evidence indicates that poor interlock,poor bone quality,and resorption of a necrotic bone bed may initiate loosening during or shortly after surgery;this forms the basis of the theory of early loosening.Biomechanical factors do affect the subsequent progression of loosening,which may increase subclinically during a long period of time.Eventually,the loosening may be detected on standard radiographs and may be interpreted as late loosening but should to be interpreted as late detection of loosening.The theory of early loosening explains the rapid early migration,the development of periprosthetic osteolysis and granulomas,the causality between wear and loosening,and largely the epidemiology of clinical failure of hip prostheses.Aspects discussed are definition of loosening,the pattern of early migration,the choice of migration threshold,the current understanding of loosening,a less exothermic bone cement,cemented taper-slip stems,a new exciting computed tomography-based technique for simpler implant migration studies,and research suggestions.
文摘Objective： To discuss if the sentinel lymph node （SLN） biopsy is able to reflect the status of the axillary lymph node and the application of this technic in clinic. Methods： Using^ 99mTc-signed dextran, SLN-biopsy （SLNB） was carried out in 182 cases with breast cancer during May 1999 to September 2006. During the operation, y-detector was used for orientation. After the SLNB, a modified radical mastectomy or breast conserving surgery were carried out to the patients, then a particular separate pathological examination of the SLN was made. Results： 178 cases of SLNB were carried out successfully, and the success rate was 97.8%, the out-checked SLN of each case ranged from 1 to 4, with an average of 2.5. All SLN was located at the first level of axilla, sensitivity of the SLN B was 93.4%, specificity was 100%, false negative rate was 6.6%, false positive rate was 0, accuracy was 97.8%, positive predictive value was 100.0%, negative predictive value was 96.7%, and Youden＇s index was 0.934. Immunohistochemical examination was carried out in 59 cases of SLN, and 14 cases showed the existences of micro-metastasis, however, metastasis had not been found in non-SLN of these cases. Conclusion： SLN is able to reflect the metastasis of the axillary lymph node, and this can suggest the necessity of the axillary dissection in clinic. The SLNB using the isotope-tracer technic is simple and accurate.
文摘Objective： The aim of this study was to compare the effect of 131I therapy of different clinical stages in postopera- tive patients with papillary thyroid carcinoma （PTC）. Methods： Eighty-seven PTC patients after surgery ablated with high doses of 131I from 2004 to 2010 were retrospectively reviewed. The efficacy of 131I therapy was assessed by three diagnostics that serum thyroglobulin （Tg） was normal or significantly reduced, 131I whole body scan （131I-WBS） was negative or the metas- tases shrank or the number of them decreased and new metastases was not found in cervical ultrasound examination. The x2 test was used to analyze 3 factors which might affect the therapeutic efficacy of 131I in patients of different clinical period, including different surgical ways （total or subtotal thyroidectomy along with half or double sides neck lymph node dissection）, age （〈 45 years and 〉 45 years） and ablative 131I dose. Results： Of 87 patients, the effective rate of 46 patients I stage was 89.13% （41）; the effective rate of 22 cases III stage was 77.27% （17）; the effective rate of 19 cases IV stage was 36.84% （7）. The corresponding intra-groups statistical difference of 3 stages was significant by x2 test （x2 = 1.72, 19.03, 6.87; P 〉 0.25, P 〈 0.005, P 〈 0.01）. The effective rate was 91.67% （44） in 48 cases undergoing total thyroidectomy; the effective rate was 53.85% （21） in 39 patients undergoing subtotal thyroidectomy. There was a significant difference between the two groups above by x2 test （x2 = 16.291; P 〈 0.005）. Conclusion： The efficacy of 131I ablation of stage I and stage III in postoperative PTC patients was almost alike, while the efficacy of stage IV descended markedly. The results was mainly determined by residual thyroid tissue size because of different surgical modus.
基金supported by the National Natural Science Foundation of China(82172044,22006109)the Medical Scientific Research Project of Jiangsu Provincial Health Commission(H2019086)+1 种基金the Postdoctoral Foundation of Jiangsu Province(2020Z372)Suzhou Medical Innovation Application Research Project(SKY2022104),China.
文摘Breast cancer is one of the most prevalent cancers worldwide,and early diagnosis and screening are vital to its successful treatment.Although medical imaging methods can assist in the early detection of breast cancer,imaging methods that are currently used for clinical diagnosis have drawbacks,such as low sensitivity and accuracy.Contrast agents are often used in diagnostic imaging to address these drawbacks.Nanocontrast agents have attracted considerable attention in recent years due to their unique physicochemical characteristics.Among these agents,inorganic nanoprobes have been substantially developed through improvements in synthesis techniques and pairings with other organic molecules.This paper mainly summarizes the specific applications of inorganic nanoprobes in the magnetic resonance imaging,fluorescence imaging,radionuclide imaging,and bimodal/multimodal imaging of breast cancer.
文摘Objective.To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection(TCPC)of different types,and to provide the selection of the best type.Methods. Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs,analyses of the distribution of blood flow from superior venous cava(SVC) and inferior venous cava(IVC)and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Results. GroupⅠ:The flow ratio of the IVC to left lung was greater than that to the right lung,P≤0.01;the flow ratio of the SVC to right lung was greater than that to the left lung,P≤0.01;and the whole pulmonary blood flow went dominantly to the left lung,P≤0.05,which is not in line with physiological distribution. GroupⅡ:the flows from the SVC and IVC were mixed in the middle of the junction and ran evenly into the right and left lungs,the whole pulmonary blood flow went to both lungs,P≥0.05. Group Ⅲ:the flow ratio of the SVC to both lungs were the same,P≥0.05,and major part from IVC went to the right lung,P≤0.01;the pulmonary blood flow go dominantly to the right lung,P≤0.05,which is in accord with physiological distribution. Group Ⅳ:the flows from the right SVC went to right lung by 100%,P≤0.01,and that from the left SVC went to left lung by 100% too,P≤0.01;the flows from IVC went dominantly to the left lung,with little part to the right lung ,P≤0.05.Conclusions. Different types of TCPC can result in different pulmonary blood distributions. The best flow distribution between the left and right lungs can be obtained by an offset of the IVC anastomosis toward the RPA with widening anastomosis for the patients without persist left superior venous cava(PLSVC).
文摘Nanogels （NGs） as soft nanosized materials have gained a variety of interests in biomedical fields. The versatile NG scaffolds with 3-dimensional spherical shape, high loading efficiency, tunable surface functionalization, and excellent biocompatibility afford their uses as carrier to load mono- or multi-mode molecular imaging contrast agents （CAs）. This review summarizes the synthesis routes and applications of NGs as CAs for molecular imaging applications including magnetic resonance （MR）, computed tomography （CT）, radionuclide, optical, and dual/mul- ti-modality imaging.
文摘Background The YIGSR is a pentapeptide, from the laminin-1 of the β1 chain, which can mediate cell adhesion and bind the 67 kD laminin receptor. The purpose is to evaluate the usefulness of 99m Tc-YIGSR, a novel tumour radiotracer, in the receptor imaging of Ehrlich ascites tumour. Methods Using S-Acetly-NH_3-MAG_3 as chelate, YIGSR, a pentapeptide from laminin, was tagged with 99m Tc. 99m Tc-YIGSR was detected in the tumour group bearing Ehrlich ascites tumour and blocked group. Tumour, normal, inflammatory and blocked groups were imaged. Results Through reverse phase Sep-Pak C_ 18 chromatogram, it was revealed that YIGSR could conjugate with S-Acetly -NH_3-MAG_3, and be radiolabelled at room temperature and neutral pH with a radiolabelling yield of 62%, and of 4% without chelate. 99m Tc-YIGSR was rapidly cleared from kidney, then liver. The imaging findings showed tumour tissue accumulated initial radioactivity at fifteen minutes after injection in the tumour group, and the uptake increased to peak at three hours with a tumour/muscle ratio (T/M) of 11.36, then cleared slowly to a T/M of 7.50 at eight hours. The tumour uptake of radiotracer in blocked group was significantly lower with T/M of 4.61 at three hours and 0.89 at eight hours. The T/M was only 3.72 at three hours and 1.29 at eight hours after injection in inflammatory group. Compared with inflammatory group and control obstructive group, the ratio of T/M in tumour group was significantly different ( P <0.001). Conclusions Using S-Acetly-NH_3-MAG_3, we radiolabelled YIGSR with 99m Tc. 99m Tc-YIGSR possesses many merits of tumour imaging: rapid visualization, high sensitivity and specificity, and satisfactory target/nontarget ratio. Our data suggest 99m Tc-YIGSR is a promising tumour radiotracer.
