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Objective To evaluate the maturity and metabolic status of heterotopic ossification(HO)by single-photon emission computed tomography(SPECT)/CT fusion bone imaging.Methods The clinical and SPECT/CT fusion bone imaging data of 57 patients with HO confirmed by pathology or follow-up were analyzed retrospectively.HO was graded by CT,and the characteristics of radioactive concentration of HO were analyzed.Results Of 57 cases,single lesion in 52 cases,and multiple lesions in 5 cases,with a total of 63 lesions,mostly located in the hip joint(55.6%,35/63)and thigh(19.0%,12/63).There were 41 lesions in the middle stage and 22 lesions in the late stage.In the visual evaluation of SPECT/CT fusion bone imaging,the middle stage lesions were mostly clumps or flakes,with moderate or high radioactive concentration(75.6%,31/41),furthermore,the concentration range was larger than or equal to the total or limited range of CT ossification(21/41,50.1%),with high concentration mainly located in the mixed areas of ossification density.The concentration of the late stage lesions was mostly non-radioactive(72.7%,16/22).Conclusion SPECT/CT fusion bone imaging can show the range,degree and maturity of HO radioactive concentration,and can accurately locate the area with osteoblastic activity,which provides scientific basis for the selection of surgical timing.
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Objective To investigate the value of single photon emission computed tomography/computed tomography(SPECT/CT)fusion imaging for post-implantation dose verification of 125I particles in patients with bone metastases.Methods Forty patients with metastatic bone tumors treated with 125I particles implantation were selected.Within 24 h after 125I particles implantation,patients underwent SPECT/CT fusion imaging and the radioactivity per unit(RPU)was calculated.The treatment planning system(TPS)was then used to obtain the isodose profiles of SPECT/CT fusion imaging results and to calculate the tumor target coverage.The patient's preoperative and postoperative 1 month clinical outcomes,including local tumour remission,pain assessment,quality of life and serum alkaline phosphatase(ALP)levels were compared,and a receiver operating characteristic(ROC)curve was applied to evaluate the predictive value of tumor target coverage on postoperative outcomes.Results The mean number of particles implanted in the target area was 32.52±12.87.Within 24 h of 125I particles implantation,SPECT/CT fusion imaging analysis confirmed a strong positive correlation between the RPU of the radioactive concentration area and the mean dose received by the patient(r=0.786,P<0.05).The predicted area under the curve(AUC)for local tumor remission,pain relief,quality of life improvement and change in ALP levels was 0.789,0.757,0.804 and 0.833,respectively.Conclusion SPECT/CT fusion imaging can be used for postoperative dose verification of 125I particles for metastatic bone tumors and has some predictive value for clinical outcomes.
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Objective:To investigate the application value of digital X-ray radiotherapy and single photon emission computed tomography(SPECT)radionuclide bone imaging in the diagnosis of intertrochanteric fracture of femur.Methods:A total of 70 patients who were diagnosed as intertrochanteric fracture of femur in Shijiazhuang People's hospital from January 2017 to December 2020 were selected,and they were divided into study group and control group according to random number method,with 35 cases in each group.Digital X-ray radiography combined with SPECT radionuclide bone imaging was used in the study group,and digital X-ray radiography was used in the control group.And then,the accuracy of the diagnostic results between the two groups were compared.Results:The radiographic examination indicated that 31 cases(88.6%)of 35 cases in the study group were confirmed,and 24 cases(68.6%)of 35 cases in the control group were confirmed.The diagnostic accuracy rate of the study group was significantly higher than that of the control group,and the difference was statistically significant(x2=4.158,P<0.05).The preoperative imaging diagnosis indicated that diagnosed number of fracture blocks in the study group was(3.57±0.50),which was significantly higher than that(2.67±0.40)in the control group,and the difference of that between two groups was statistically significant(t=8.315,P<0.05).In the actual intraoperative examining for bone continuity,5 cases were continuity and 30 cases were non-continuity.In the bone stability,13 cases were stability and 22 cases were non-stability.The study group was closer to intraoperative bone continuity and bone stability,and the differences of them between two groups were statistically significant(x2=12.857,4.644,P<0.05),respectively.Conclusion:The combination of digital X-ray radiography and SPECT radionuclide bone imaging has higher diagnostic value for intertrochanteric fracture of femur,which can provide important reference for clinical diagnosis.
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【Objective】 To evaluate the role of quantitative flow ratio (QFR) in percutaneous coronary intervention (PCI) by using regadenoson stress dynamic single-photon emission computed tomography (D-SPECT). 【Methods】 We selected 200 patients with unstable angina admitted to Department of Cardiology, Hebei Medical University First Hospital, from June 31, 2021 to June 31, 2023 for elective PCI. The patients were aged 57.56±8.23 years and were randomly divided into a conventional group (n=100) and a QFR group (n=100) according to a random number table. The trial was conducted using a double-blind method. The conventional group received PCI treatment based on the experience of the physician, while the QFR group received PCI treatment based on the QFR measurement results. All enrolled patients underwent pre-operative and 7-day post-operative D-SPECT stress imaging using regadenoson stress D-SPECT, and their images were acquired from short axis, vertical long axis, and horizontal long axis to calculate the total myocardial perfusion score and the total myocardial ischemia segment number under the distribution of 17 myocardial segments. 【Results】 There was no significant difference in the number of myocardial ischemia segments (7.59±3.14 vs. 7.48±3.36, P=0.811) or the total myocardial perfusion score (15.87±7.61 vs. 15.63±5.97, P=0.860) between the two groups before PCI. The number of myocardial ischemia segments (5.58±3.36 vs. 6.51±2.14, P=0.020) and the total myocardial perfusion score (10.55±4.41 vs. 12.96±6.50, P=0.002) in the QFR group were significantly better than those in the conventional group 7 days after PCI (P<0.05). 【Conclusion】 Applying QFR guidance for PCI can better improve the degree of myocardial ischemia in patients.
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@#The combination of conventional single-photon emission computed tomography (SPECT) and computed tomography (CT) may display the morphological changes of lesions and distribution of imaging agents, which is effective to improve the imaging sensitivity and specificity of tumors and non-tumor diseases. SPECT/CT is feasible to analyze the anatomical structure and metabolic status through displaying multi-site lesions with single imaging, thereby improving differential diagnosis and diagnostic accuracy of diseases. In addition, the novel mixed SPECT/CT device shortens the duration of image acquisition and provides precise attenuation correction and fusion imaging, which provides a scientific basis for rational selection of treatment regimens in clinical practice. This review describes the advances in clinical application of SPECT/CT.
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Objective @#To investigate the feasibility of epidural catheters in parotid gland duct anastomosis and the function of the affected side gland after parotid gland duct anastomosis. @* Methods@# Thirteen patients who were treated in the Department of Oral and Maxillofacial Surgery of Xuzhou Central Hospital using an epidural catheter as the scaffold for parotid gland catheter anastomosis were enrolled from Jan. 2019 to June 2021. The swelling, salivary fistula and catheter patency in the parotid gland area were evaluated two weeks after the operation. 99mTcO4- single photon emission computed tomography (SPECT) was used for quantitative detection of salivary gland secretion function@*Results@# Thirteen patients had no swelling or salivary fistula in the parotid gland area of the affected side two weeks after the operation, and the catheter secretion was unobstructed. There was no significant difference in the uptake rate between the parotid gland on the affected side and the parotid gland on the healthy side (t = -0.859, P = 0.399), and there was no significant difference in the excretion rate between the parotid gland on the affected side and the parotid gland on the healthy side (t = 0.693, P = 0.495). The parotid gland excretion function of the affected side was excellent three months after the operation.@*Conclusion @#Parotid duct anastomosis with an epidural catheter as the stent has good feasibility, and parotid gland secretion function recovers well after the operation, which is worthy of clinical application.
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Objective@#To investigate the changes of ambient dose equivalent rate in 99mTcO4- single photon emission computed tomography (SPECT) of the thyroid among patients with hyperthyroidism, so as to provide insights into radiation protection guidance.@*Methods@#Patients with hyperthyroidism who underwent 99mTcO4- SPECT of the thyroid in a tertiary hospital were enrolled. The ambient dose equivalent rate was measured at different time points following 99mTcO4- infection and at sites with different distances from patients' neck, and the effects of time post-injection, distance from patients' neck, 24-hour thyroidal radioiodine uptake and thyroid weight on the ambient dose equivalent rate were examined using a generalized linear mixed model.@*Results@#Totally 100 patients with hyperthyroidism were enrolled, including 24 men and 76 women and with a mean age of (38.5±14.0) years. The generalized linear mixed model was statistically significant (F=6 610.165, P<0.001), and patients' thyroid weight, time post-injection and distance from patients' neck significantly affected the ambient dose equivalent rate (F=57.967, 15 988.574, 11 200.645, all P<0.001), and the ambient dose equivalent rate positively correlated with patients' thyroid weight and negatively correlated with time post-injection and distance from patients' neck.@*Conclusions@#The ambient dose equivalent rate is affected by patients' thyroid weight, time post-injection and distance from patients' neck among patients with hyperthyroidism undergoing 99mTcO4- SPECT of the thyroid. Delay in contact with patients or keeping distance from patients may be effective for radiation protection.
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With the changes of the disease spectrum of liver transplantation and organ allocation system, more and more patients complicated with cardiovascular complications have entered the waiting list for liver transplantation. However, surgical stress, severe infection and adverse reactions of immunosuppressive drugs will significantly increase the risk of postoperative cardiac complications and affect the short-and long-term survival of the recipients. Therefore, comprehensive evaluation of cardiac structure and function of the recipients before liver transplantation is of significance for improving clinical prognosis of the recipients. In this article, the main causes for the increased risk of heart disease during the perioperative period of liver transplantation, the time and methods of heart disease risk assessment for liver transplant recipients were reviewed, and existing assessment approaches for common heart diseases before liver transplantation were illustrated, aiming to provide reference for further reducing the incidence of heart complications after liver transplantation, improving the survival rates of grafts and recipients and enhancing clinical prognosis.
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Reflex epilepsy is a type of partial or generalized seizure induced by specific or nonspecific stimulation in individuals without a prior history of seizures. Mahjong epilepsy is a special form of complex reflex epilepsy induced by playing or watching mahjong, with a low incidence rate and complex pathogenesis. Due to the lack of comprehensive understanding, clinical studies of mahjong epilepsy are still mainly based on case reports. Now, we will analyze and summarize the etiology, pathogenesis, clinical diagnosis, electroencephalogram, treatment, and prognosis of mahjong epilepsy to raise awareness of mahjong epilepsy among clinical medical workers.
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ABSTRACT Background: the diagnosis of Parkinson's disease (PD) can be challenging, especially in the early stages, albeit its updated and validated clinical criteria. Recent developments on neuroimaging in PD, altogether with its consolidated role of excluding secondary and other neurodegenerative causes of parkinsonism, provide more confidence in the diagnosis across the different stages of the disease. This review highlights current knowledge and major recent advances in magnetic resonance and dopamine transporter imaging in aiding PD diagnosis. Objective: This study aims to review current knowledge about the role of magnetic resonance imaging and neuroimaging of the dopamine transporter in diagnosing Parkinson's disease. Methods: We performed a non-systematic literature review through the PubMed database, using the keywords "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". The search was restricted to articles written in English, published between January 2010 and February 2022. Results: The diagnosis of Parkinson's disease remains a clinical diagnosis. However, new neuroimaging biomarkers hold promise for increased diagnostic accuracy, especially in earlier stages of the disease. Conclusion: Future validation of new imaging biomarkers bring the expectation of an increased neuroimaging role in the diagnosis of PD in the following years.
RESUMO Antecedentes: O diagnóstico da doença de Parkinson (DP) pode ser desafiador, principalmente nas fases iniciais da doença, embora tenha critérios clínicos atualizados e validados. Os avanços recentes em neuroimagem na DP, além do seu papel já consolidado de excluir causas secundárias e outras causas neurodegenerativas de parkinsonismo, tem contribuído para uma maior confiabilidade no diagnóstico em diferentes estágios da doença. Nesta revisão, nós destacamos os principais avanços de ressonância magnética e imagem do transportador de dopamina em auxiliar o diagnóstico de DP. Objetivo: realizar uma revisão acerca do conhecimento atual sobre o papel da ressonância magnética e imagem do transportador de dopamina no diagnóstico de doença de Parkinson. Método: Realizamos uma revisão não sistemática da literatura através da base de dados PubMed, utilizando as palavras-chave "Parkinson", "magnetic resonance imaging", "diffusion tensor", "diffusion-weighted", "neuromelanin", "nigrosome-1", "single-photon emission computed tomography", "dopamine transporter imaging". A busca foi restrita a artigos escritos em inglês, publicados entre janeiro de 2010 e fevereiro de 2022. Resultados: O diagnóstico de doença de Parkinson continua sendo um diagnóstico clínico, contudo, novos biomarcadores de neuroimagem são promissores para o aumento da acurácia diagnóstica, especialmente em fases mais precoces da doença. Conclusão: A validação futura de novos biomarcadores de imagem traz a expectativa de um maior papel da neuroimagem no diagnóstico de doença de Parkinson nos próximos anos.
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Transthyretin-related amyloid cardiomyopathy (ATTR-CM) is a disease caused by the depo-sition of insoluble amyloid fibers formed by the misfolding of transthyretin precursor protein in the intercellular space of cardiomyocytes. This lesion may lead to myocardial dysfunction, cogestive heart failure, and death.When diagnosed earlier, the patient can be treated with drugs as soon as possible to intervene in the progress of the disease, so as to effectively improve the patient's prognosis.99mtechnetium-pyrophosphate (99Tcm-PYP)single-photon emission computed tomography (SPECT) has been widely used in the imaging examination of cardiac amyloidosis (CA) in recent years. While achieving early non-invasive diagnosis, accurate pathological classification can be obtained through Perugini visual score analysis, semi-quantitative analysis of heart to contralateral lung (H/CL) ratio, and SPECT image analysis. This article presents the application, methods, and the precautions of 99Tcm-PYPSPECT in the diagnosis of ATTR-CM, aiming to provide clinical reference for the application of this technology.
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Abstract Purpose: Budget cuts among other factors undermine the use of state-of-the-art equipment by many research groups. This doesn't mean that their scientific data are not reliable or top-notch. Resort to adaptations is a recurrent need in their reality. The aim of this study was to assess whether scintigraphy with 99mTcO4 is effective in evaluating the functionality of thyroid grafts after cryopreservation in rats. Material and methods: 24 rats were randomly distributed into 3 groups: Control Group (CG), without surgical procedure, Hypothyroidism Group (HTG), submitted to total thyroidectomy, and Transplanted Group (TG), with total thyroidectomy and cryopreservation of the thyroid gland for 7 days followed by grafting of a thyroid lobe. A protocol using a gamma camera imaging was conducted fourteen weeks after transplantation, and the whole body 99mTc, focusing on the topic of heterotopic thyroid uptake was evaluated. Results: The images acquired had good quality with no noise and artifacts that could jeopardize its analysis. On the 14th day, HTG displayed no thyroid uptake, and the TG had a clear uptake of the thyroid graft in the topography of the biceps femoris muscle. Presented data also showed that both equipment spatial resolution and alignment (4.375 mm) did not interfere with the physiological uptake of 99mTc by the thyroid graft. Conclusion: The viability and functionality of cryopreserved thyroid autotransplantation in rats who underwent total thyroidectomy were successfully accessed by the scintigraphy protocol developed. HIGHLIGHTS Adaptations in validated methods are a recurrent trend due to limited budgets which does not diminish their functionality. Scintigraphy with 99mTcO4 is effective in evaluating the functionality of thyroid grafts after cryopreservation in rats. It is possible to adapt human SPECT for other animals for clinical and research purposes.
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Objective:To investigate the diagnostic efficacy of 99Tc m-MIBI SPECT dual-phase imaging combined with rapid parathyroid hormone detection in thyroid cancer with suspected parathyroid mass. Methods:Data of 76 cases of thyroid cancer with suspected cervical parathyroid gland tumors receiving colorectal ultrasonography or CT examination in Thyroid Surgery Department of the Affiliated Cancer Hospital of Zhengzhou University were retrospectively analyzed. Blood samples were taken before surgery to detect parathyroid hormone. Parathyroid hormone was quickly detected after clamping the tumor blood vessels during surgery. Based on the postoperative pathological results, the sensitivity, specificity, accuracy and consistency of various diagnostic methods were evaluated. The ROC curve was drawn by measuring the value of the parathyroid gland concentration after reduction of the tumor blood vessels by clamping the tumor.Results:The sensitivity and accuracy of the 99Tc m-MIBI SPECT dual-phase imaging combined with the rapid detection of parathyroid hormone in diagnosis of suspected parathyroid tumors were (96.5%, 93.4%) better than the 99Tc m-MIBI SPECT dual-phase imaging methods (77.6%, 78.9%) and intraoperative rapid detection methods (86.2%, 82.8%) , and had a high consistency with the results of pathological examination, Kappa value of 0.81. The combined detection rate of suspected parathyroid tumors was significantly higher than that of 99Tc m-MIBI SPECT dual-phase imaging and rapid intraoperative detection, but there was no significant difference between 99Tc m-MIBI SPECT dual-phase imaging and intraoperative rapid detection. The area under the ROC curve of the reduction ratio a value after clamping the blood vessels of the tumor was 0.774, and the standard error was 0.073. The difference was statistically significant ( P<0.001,95% CI:0.631-0.918) . According to the results obtained by the ROC, the index (sensitivity + specificity-1) was plotted on the ordinate and a was the abscissa. The maximum value of the Jordan index was 0.584. The a value corresponding to this point was 0.52. 0.52 is the DCP value. The corresponding sensitivity, specificity, accuracy was 86.2%,72.2%,and 82.9%. Conclusion:99Tc m-MIBI SPECT dual-phase imaging combined with rapid parathyroid hormone detection during surgery has good diagnostic value for thyroid cancer with suspected parathyroid mass, and is completely consistent with pathological diagnosis.
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Objective:To discuss the problems existing in the implementation of the Chinese health industry standard WS 523-2019 by testing SPECT device.Methods:Under the WS 523-2019 standards, a total of 10 SPECT devices were tested with regard to their SPECT reconstructed spatial resolution (SRSR), system planar sensitivity (SPS), system spatial resolution (SSR), whole body system spatial resolution (WSSR), intrinsic uniformity (IU), intrinsic count rate performance (ICR), intrinsic spatial resolution (ISR) and intrinsic spatial linearity(ISL).Result:Under the requirements of WS 523-2019 standards for qualified limits, there are 3 devices with ISL unqualified and the rest of the performances qualified. The new standards basically can meet the clinical requirements and reflected the overall performance of SPECT.Conclusions:The distance between the radiation source and the surface of the detector has great influence on the spatial resolution.In the measurement of ISL, there must be a lead grid separately in the x and y directions. The lead grids with the parallel slits shall be positioned on the detector with the center slit centered on the detector. It is suggested to add rotation center in the new standards.
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Resumen Los anticuerpos monoclonales marcados con radionucleidos fueron en sus inicios ampliamente empleados para el estudio de diversas enfermedades, fundamentalmente oncológicas mediante la inmunogammagrafía. Estos fueron poco a poco sustituidos por moléculas con mejores prestaciones como los péptidos y la 18F-fluordesoxiglucosa (18F-FDG). No obstante, en el presente siglo, la amplia introducción de la inmunoterapia produjo un cambio de paradigma en cuanto al empleo de los anticuerpos monoclonales radiomarcados para la adecuada selección y seguimiento de los pacientes a ser tratados con inmunoterapia, resurgiendo la inmunotomografía por emisión de fótón único (inmuno-SPECT), la inmunotomografía por emisión de positrones (inmuno-PET) y la imagen corregistrada con la tomografía axial computarizada (TAC), como modalidades de gran valor en el manejo del cáncer. El objetivo del presente trabajo fue brindar una panorámica acerca de la evolución de la imagen nuclear con anticuerpos monoclonales radiomarcados y sus principales aplicaciones en el tiempo, fundamentalmente en el estudio de los pacientes con cáncer.
Abstract In the beginning, radionuclide-labeled monoclonal antibodies were widely employed for the study of various diseases, mainly oncological, by immunoscintigraphy. They were gradually replaced by molecules with better performance such as peptides and 18F-FDG. However, in the present century, the wide introduction of immunotherapy produced a paradigm shift in the use of radiolabeled monoclonal antibodies for the proper selection and follow-up of patients to be treated with immunotherapy, re-emerging of the immune-single photon emission tomography (immuno-SPECT), the immune-positron emission tomography (immuno-PET) and the co-registered image with computed tomography (CT) as imaging modalities of great value in the management of cancer. The aim of the present work was to provide an overview of the evolution of nuclear imaging with radiolabeled monoclonal antibodies and their main applications over the time, mainly in the study of patients with cancer.
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@#Reversible cerebral vasoconstriction syndrome (RCVS) presents with characteristic clinical, brain imaging, and angiographic findings. The most common clinical feature of RCVS is a severe acute headache, which is often referred to as a thunderclap headache owing to the nature of its presentation. It may occur spontaneously or may be provoked by various precipitating factors. We present two cases of RCVS concomitant with cerebral venous sinus thrombosis (CVST). Patient 1 was a 42-yearold woman admitted to our hospital with severe headache radiating to the neck, with associated vomitting. She had a history of ovarian cancer and underwent an operation for resection of the tumor a month prior to presentation. After resection, her estradiol (E2) levels were reduced from 288 pg/ ml to 31 pg/ml (normal range, 0-49 pg/ml). Initial imaging upon admission to our hospital revealed left posterior convexity subarachnoid hemorrhage. Magnetic resonance angiography (MRA) showed findings consistent with RCVS affecting the left posterior cerebral artery. Magnetic resonance venography (MRV) showed CVST of the left transverse and sigmoid sinuses. Single photon emission computed tomography (SPECT) showed a left posterior ischemic lesion. These findings improved following treatment with nimodipine and anticoagulant. Patient 2 was a 39-year-old woman presented with holocranial headache associated with vomiting. She was diagnosed with an ovarian tumor. She underwent an operation three months prior to presentation. After tumor resection, her E2 level decrease from 193 pg/ml to 19 pg/ml (normal range, 0-49 pg/ml). MRA confirmed the presence of a vasospasm involving the right anterior cerebral artery. MRV confirmed the presence of thrombosis involving the superior sagittal sinus. She was discharged on postpartum day 31 without neurological deficits after treatment with anticoagulants. At 3 month follow-up, both MRA and MRV were within the normal limits. In conclusion, this is the first report of two women diagnosed with RCVS with concomitant CVST following ovarian tumor resection. The rapid change of perioperative E2 levels may have contributed to the development of CVST and RCVS.
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@#Megaprosthesis is used to restore the form and function of massive skeletal defects, but it is accompanied by risks of failure, mainly due to perimegaprosthetic infection (PMI). In practice, the diagnosis of infected megaprosthesis among patients with a high index of clinical suspicion, elevated serological markers, and multiple negative or inconclusive imaging can be very challenging and poses a diagnostic conundrum to many orthopaedic surgeons. We present the case of a symptomatic 26-year-old female with large B-cell lymphoma who developed cellulitis with suspected complication of PMI 15 months post-implantation. The combination of advanced nuclear medicine imaging strategies, i.e., 99mTc-besilesomab/ 99mTc-sulfur colloid scintigraphy with hybrid single-photon emission computed tomography/computed tomography (SPECT/CT) scanning helps to characterise and delineate both infections. Invasive procedures such as joint aspiration and biopsy were avoided, and the patient was successfully treated with antibiotics. Hence, we report a case where advanced imaging modalities were decisive in the investigation of PMI.
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RESUMEN El hiperparatiroidismo terciario es una complicación presentada en pacientes con enfermedad renal crónica llevados a trasplante renal cuyo manejo quirúrgico requiere de la ubicación mediante imágenes diagnosticas para garantizar el éxito de esta intervención. Se presenta caso de mujer en hemodiálisis crónica que presentó hiperparatiroidismo terciario por hiperplasia paratiroidea confirmada con Tc-99m MIBI SPECT.
ABSTRACT Tertiary hyperparathyroidism is a complication presented in patients with chronic kidney disease subjected to renal transplantation whose surgical management requires location through diagnostic images to guarantee the success of this intervention. We present the case of a woman on chronic hemodialysis who presented tertiary hyperparathyroidism due to parathyroid hyperplasia confirmed by Tc-99m MIBI SPECT.
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Purpose: The aim of the study is to study the feasibility of gamma-ray-detection-based precision dose measurement of 125I seed brachytherapy in solid water. Materials and Methods: Seven group 125I seeds with different activities were put into a hole in the center of solid water individually. Each group had ten seeds, and the seed activity ranged from 1.48 × 107 Bq to 3.7 × 107 Bq. Single-photon emission computed tomography/computed tomography (SPECT/CT) was used to scan the seeds perpendicular to the long axis of the seed, with a slice thickness of 3.75 mm. The radioactive count values (x) of the radioactive concentration around the seeds were collected at a distance of 1–15 mm from the center of the seeds, while the corresponding doses (Y) (Gy) were calculated. SPSS 18.0 was used to analyze the relationship between the count value and the dose. Results: With the same seed activity, the count values became smaller according to the distance from the center of the seeds. The count values at the same point had an increasing trend according to the activity. This is similar to the doses calculated at the same point. There was an exponential relationship between the dose around the 125I seeds, and the radioactive count value detected by SPECT/CT. Correlative curves between the dose and radioactive count value detected by SPECT/CT of different-activity 125I seeds were fitted. The formulas of the dose and radioactive count with different seed activity were in the form of Y = b0 (b1)x. The constant b0 ranged from 1.48 to 3.93, according to the seed activity, while b1 was 1.006 for every seed's activity. Conclusion: The count value around the 125I seed can be detected accurately by SPECT/CT, and then can be quantified. This study provided useful experiment data for the precision measurement of 125I seed implantation. Radiation detection-based dose measurement may become a new noninvasive technology for the dynamic dosimetry verification method after brachytherapy