Disincronía miocárdica en pacientes sometidos a estudio de Spect gatillado y análisis de fase / Myocardial dyssynchrony in patients undergoing gated SPECT and phase analysis

Introducción: la perfusión miocárdica mediante SPECT gatillado (tomografía computarizada de emisión de fotón único) y análisis de fase permiten evaluar la disincronía mecánica y la fracción de eyección, indicando quienes podrían responder a la terapia de resincronización cardíaca. Objetivo: describir la frecuencia de disincronía miocárdica y su relación con los resultados del SPECT en el Hospital de San José de Bogotá entre mayo 2018 y febrero 2019. Metodología: estudio transversal en mayores de 18 años, con electrocardiograma de no más de 6 meses y SPECT gatillado. Para la información sociodemográfica, antecedentes cardíacos, parámetros de electrocardiograma y resultados del SPECT se empleó estadística descriptiva y análisis de correspondencias múltiples. Resultados: se incluyeron 539 pacientes con edad promedio de 68 años, 59.8% con sobrepeso y obesidad, 47.7% en clase funcional NYHA (New York Heart Association) III y IV, 48.4% fumadores y 26.9% diabéticos; 48.1% tenían cateterismo cardíaco y 45.3% infarto agudo de miocardio; en 31% la fracción de eyección del ventrículo izquierdo < 50%. La disincronía se determinó con un ancho de banda >135°; hubo disincronía en 202 pacientes (37.5%) que se relacionó con: género masculino, sobrepeso, diabetes, tabaquismo, infarto agudo del miocardio, colocación de stent, fracción de eyección del ventrículo izquierdo <40% o entre 40%-50% y dilatación isquémica transitoria (TID) >1.22 o entre 1.12-1.22. Discusión y conclusiones: el uso de la nueva herramienta del análisis de fase de medicina nuclear es factible y útil para determinar los pacientes respondedores a la terapia de resincronización cardíaca.

Introduction: Myocardial perfusion gated SPECT (simple photon emission computed tomography) with phase analysis allows the assessment of mechanical dyssynchrony and ejection fraction, for prediction of response to cardiac resynchronization therapy. Objective: to describe myocardial dyssynchrony frequency and its relationship with SPECT results at Hospital de San José de Bogotá between May 2018 and February 2019. Methodology: cross-sectional study in patients aged over 18 years, with a less than 6 months electrocardiogram and gated SPECT. Sociodemographic data, cardiovascular history, electrocardiogram parameters and SPECT results were evaluated using descriptive statistics and multiple correspondence analysis. Results: five-hundred-thirty-nine patients with a mean age of 68 years were included, 59.8% had overweight and obesity, 47.7% were NYHA (New York Heart Association) functional class III and IV, 48.4% smokers and 26.9% diabetics; 48.1% received cardiac catheterization and 45.3% had history of acute myocardial infarction; left ventricular ejection fraction was < 50% in 31%. Dyssynchrony was determined with a >135° bandwidth; dyssynchrony was evidenced in 202 patients (37.5%) and was related to male gender, overweight, diabetes, smoking, acute myocardial infarction, stent placement, left ventricular ejection fraction <40% or 40%-50% and transient ischemic dilation (TID) >1.22 or 1.12-1.22. Discussion and conclusions: the new nuclear medicine phase analysis tool is feasible and useful to identify cardiac resynchronization therapy responders.

Conditions for the determination of intrinsic uniformity and intrinsic spatial linearity of SPECT / 中国辐射卫生

Objective To address the absence of matrix specified for the determination of intrinsic uniformity in the current standard, and to investigate the effect of source distances on intrinsic spatial linearity, the intrinsic uniformity and intrinsic spatial linearity of 16 probes in eight SPECT devices were measured and analyzed with different matrices and source distances, in order to determine the optimal measurement conditions. Methods According to the standard Specification for Testing of Quality Control in Gamma Cameras and Single Photon Emission Computed Tomograph (SPECT) (WS 523—2019), the intrinsic uniformity was measured using 64 × 64 and 256 × 256 matrices and the intrinsic spatial linearity was measured using of 1.7 and 3 m source distances. Results When intrinsic uniformity was measured with the 64 × 64 matrix, more than 50% of the probes showed lower values. When intrinsic spatial linearity was measured with the 3 m source distance, more probes showed lower values. Conclusion The 64 × 64 matrix is recommended for the determination of intrinsic uniformity and a source distance of ＞5 FOV is recommended for the measurement of intrinsic spatial linearity.

Viabilidade do Implante de Eletrodo Ventricular Esquerdo na Terapia de Ressincronização Cardíaca Guiada por Gated SPECT e Remodelamento Ventricular / Feasibility of Left Ventricle Lead Implantation in Cardiac Resynchronization Therapy Guided by Gated SPECT and Ventricular Remodeling

Resumo Fundamento A terapia de ressincronização cardíaca (TRC) pode beneficiar pacientes com insuficiência cardíaca (IC) avançada. O índice de excentricidade anormal por gated SPECT está relacionado a alterações estruturais e funcionais do ventrículo esquerdo (VE). Objetivo O objetivo do presente estudo foi avaliar a viabilidade do implante de eletrodos do VE guiado por análise de fase e sua relação com o remodelamento ventricular. Métodos Dezoito pacientes com indicação de TRC foram submetidos à cintilografia miocárdica para orientar o implante, avaliando-se os parâmetros de excentricidade e forma ventricular. P < 0,05 foi adotado como significância estatística. Resultados Na linha de base do estudo, a maioria dos pacientes foi classificada como NYHA 3 (n = 12). Após a TRC, 11 dos 18 pacientes foram reclassificados para um menor grau de limitação funcional. Além disso, a qualidade de vida dos pacientes melhorou após a TRC. Foram observadas reduções significativas na duração do QRS, intervalo PR, índice de forma diastólica final, índice de forma sistólica final, volume sistólico e massa miocárdica pós-TRC. O eletrodo do VE da TRC foi posicionado concordante, adjacente e discordante em 11 (61,1%), 5 (27,8%) e 2 (11,1%) pacientes, respectivamente. A excentricidade sistólica e diastólica final demonstrou remodelamento reverso após a TRC. Conclusões O implante de eletrodo do VE em TRC guiado por cintilografia gated SPECT é viável. A colocação do eletrodo concordante ou adjacente ao último segmento a se contrair foi um determinante do remodelamento reverso.

Abstract Background Cardiac resynchronization therapy (CRT) may benefit patients with advanced heart failure (HF). Abnormal eccentricity index by gated SPECT is related to structural and functional alterations of the left ventricle (LV). Objective The aim of this study is to evaluate the feasibility of LV lead implantation guided by phase analysis and its relationship to ventricular remodeling. Methods Eighteen patients with indication for CRT underwent myocardial scintigraphy for implant orientation, and eccentricity and ventricular shape parameters were evaluated. P < 0.05 was adopted as statistical significance. Results At baseline, most patients were classified as NYHA 3 (n = 12). After CRT, 11 out of 18 patients were reclassified to a lower degree of functional limitation. In addition, patients' quality of life was improved post-CRT. Significant reductions were observed in QRS duration, PR interval, end-diastolic shape index, end-systolic shape index, stroke volume, and myocardial mass post-CRT. The CRT LV lead was positioned concordant, adjacent, and discordant in 11 (61.1%), 5 (27.8%), and 2 (11.1%) patients, respectively. End-systolic and end-diastolic eccentricity demonstrated reverse remodeling post-CRT. Conclusions LV lead implantation in CRT guided by gated SPECT scintigraphy is feasible. The placement of the electrode concordant or adjacent to the last segment to contract was a determinant of reverse remodeling.

Dosis efectivas asociadas a estudios híbridos SPECT-CT en pacientes adultos / Effective dose associated to hybrid SPECT-CT imaging in adult patients / Doses eficazes associadas a estudos de SPECT-CT híbridos em pacientes adultos

Introducción: la técnica de imagen híbrida de SPECT-CT combina la imagen de la tomografía por emisión de fotón único (SPECT) con el estudio de tomografía computada (TC), obteniendo información funcional y anatómica en un mismo estudio. La dosis efectiva total de radiación ionizante recibida en los estudios SPECT-CT puede ser estimada a partir de la dosis efectiva atribuible a la actividad administrada del radiofármaco y la dosis efectiva del componente de tomografía computada (TC). Objetivos: estimar la dosis efectiva total en los protocolos SPECT-CT utilizados en población adulta y determinar el aporte adicional del estudio TC sobre la dosis efectiva total. Método: se evaluaron 258 estudios SPECT-CT para estimar la dosis efectiva total aportada por la administración de los radiofármacos y los estudios de TC de baja dosis. Para estimar el aporte de ambos componentes se utilizaron factores de conversión específicos de cada radiofármaco y región explorada mediante TC. Resultados: la dosis efectiva total (media ± DS) en los estudios SPECT-CT fueron: 12,4 ± 1,44 mSv en el estudio de perfusión miocárdica, 1,14 ± 0,25 mSv en ganglio centinela de mama, 8,6 ± 0,6 mSv paratiroides, 1,48 ± 1,02 mSv tiroides y los estudios óseos de las regiones de cuello 4,5 ± 0,3, tórax 6,07 ± 0,3 mSv, abdomen y pelvis 6,1 ± 0,3 mSv. La dosis de radiación aportada por el estudio TC se encuentra entre 0,46 mSv para la región del tórax en el estudio de ganglio centinela de mama y 2,3 mSv para el SPECT-CT óseo en la región de abdomen y pelvis. Conclusión: se logró estimar la dosis efectiva en los protocolos SPECT-CT de uso clínico más frecuente en población adulta y el aporte de los estudios TC a la dosis efectiva total siendo relativamente baja comparado con la dosis aportada por los radiofármacos administrados con la excepción del estudio de ganglio centinela donde la contribución del componente TC es aproximadamente la mitad de la dosis efectiva total.

Introduction: SPECT-CT Hybrid image technique combines the SPECT (single-photon emission computed tomography) image with the CT (computerized tomography) image to obtain both functional and anatomical images in the same study. The total effective ionizing radiation dose received in SPECT-CT studies may be estimated based on the effective dose from the radiopharmaceutical administered and the effective dose from the CT (computerized tomography) component. Objectives: the study aims to estimate the total effective dose in SPECT-CT protocols applied for the adult population, and to determine the additional contribution from the CT component to the total effective dose. Method: 258 SPECT-CT studies were evaluated to estimate the total effective dose from the administration of radiopharmaceuticals and low dose CT studies. Specific conversion factors for each radiopharmaceutical and area of the body explored with the CT were used to estimate radiation doses from both components. Results: total effective dose (average ± SD) in the SPECT-CT studies was: 12.4 ± 1.44 mSv in the myocardial perfusion study, 1.14 ± 0.25 mSv in the breast sentinel lymph node study, 8.6 ± 0.6 mSv in the parathyroid study, 1.48 ± 1.02 mSv in the thyroid study. As to bone studies, doses found were: 4.5 ± 0.3, in neck studies, 6.07 ± 0.3 mSv in thoracic studies and 6.1 ± 0.3 mSv in abdominal and pelvic studies. The radiation dose from the CT study ranges from 0.46 mSv for the thoracic region on the breast sentinel lymph node study to 2.3 mSv for the bone SPECT-CT study of the abdominal and pelvic region. Conclusions: we managed to estimate the effective dose in the the most frequently used SPECT-CT protocols for the adult population and the contribution of CT studies to the total effective dose. It was found to be relatively low when compared to the dose contributed by the radiopharmaceuticals administered, with the exception of the sentinel lymph node study for which the contribution from the CT study is approximately half the total effective dose.

Introdução: a técnica de imagem híbrida SPECT-CT combina a imagem de tomografia por emissão de fóton único (SPECT) com o estudo de tomografia computadorizada (TC), obtendo informações funcionais e anatômicas no mesmo estudo. A dose efetiva total de radiação ionizante recebida em estudos SPECT-CT pode ser estimada a partir da dose efetiva atribuível à atividade administrada do radiofármaco e da dose efetiva do componente de tomografia computadorizada (TC). Objetivos: estimar a dose efetiva total nos protocolos SPECT-CT utilizados na população adulta e determinar a contribuição adicional do estudo de TC na dose efetiva total. Método : 258 estudos SPECT-CT foram avaliados para estimar a dose efetiva total fornecida pela administração de radiofármacos e estudos de TC de baixa dose. Para estimar a contribuição de ambos os componentes, foram utilizados fatores de conversão específicos para cada radiofármaco e região explorada pela TC. ⁠ Resultados: a dose efetiva total (média ± DP) nos estudos SPECT-CT foi: 12,4 ± 1,44 mSv no estudo de perfusão miocárdica, 1,14 ± 0,25 mSv no linfonodo sentinela mamário, 8,6 ± 0,6 mSv paratireoide, 1,48 ± 1,02 mSv estudos de tireoide e ossos das regiões do pescoço 4,5 ± 0,3, tórax 6,07 ± 0,3 mSv, abdômen e pelve 6,1 ±0,3mSv. A dose de radiação fornecida pelo estudo de TC está entre 0,46 mSv para a região do tórax no estudo do linfonodo sentinela da mama e 2,3 mSv para o SPECT-CT ósseo na região do abdome e pelve. Conclusão: foi possível estimar a dose efetiva nos protocolos de SPECT-CT mais utilizados clinicamente na população adulta e a contribuição dos estudos de TC para a dose efetiva total, sendo relativamente baixa em relação à dose fornecida pelos radiofármacos administrados com a exceção do estudo do linfonodo sentinela onde a contribuição do componente TC é aproximadamente metade da dose efetiva total.

Characterization of the nigroestriatal system in a sample of patients with amyotrophic lateral sclerosis / Caracterização do sistema nigroestriatal em uma amostra de pacientes com esclerose lateral amiotrófica

Abstract Background The coexistence of amyotrophic lateral sclerosis (ALS) with clinical forms of Parkinson disease (PD), although uncommon, is found to a greater degree than one would expect by chance. The pathological mechanisms of ALS and PD are still not fully understood, and the coexistence of these two diseases suggests that they could share mechanisms in common. Objective Here we present a sample of patients with clinically definitive or probable ALS who were evaluated with single-photon emission computed tomography SPECT/TRODAT and compared with non-ALS controls. Methods Patients with clinically definite or probable ALS were assessed with the amyotrophic lateral sclerosis functional rating scale (ALSFRS) to define severity and had their demographic data collected. The TRODAT results of patients with ALS were compared with those of patients with a diagnosis of PD with less than 10 years of duration, and with patients with a diagnosis of others movement disorders not associated with neurodegenerative diseases. Results A total of 75% of patients with ALS had TRODAT results below the levels considered normal; that was also true for 25% of the patients in the control group without neurodegenerative disease, and for 100% of the patients in the PD group. A statistically significant difference was found between patients with ALS and the control group without neurodegenerative disease in the TRODAT values < 0.05. Conclusions Our study fits with the neuropathological and functional evidence that demonstrates the existence of nigrostriatal dysfunction in patients with ALS. Further research to better understand the role of these changes in the pathophysiological process of ALS needs to be performed.

Resumo Antecedentes A coexistência da esclerose lateral amiotrófica (ELA) com formas clínicas da doença de Parkinson (DP), embora incomum, é encontrada em um grau maior do que seria esperado ao acaso. Os mecanismos patológicos da ELA e da DP ainda não são totalmente compreendidos e a coexistência dessas duas doenças sugere que elas podem compartilhar mecanismos em comum. Objetivo Apresentamos uma amostra de pacientes com ELA clinicamente definida ou provável que foram avaliados com tomografia computadorizada por emissão de fóton único (SPECT)/TRODAT e comparados com controles sem ELA. Métodos Pacientes com ELA clinicamente definida ou provável foram avaliados com a escala funcional de esclerose lateral amiotrófica (ALSFRS) para definir a gravidade e foram coletados os seus dados demográficos. Os resultados do TRODAT de pacientes com ELA foram comparados com aqueles de pacientes com diagnóstico de DP com menos de 10 anos de duração e com pacientes com diagnóstico de outros distúrbios do movimento não associados a doenças neurodegenerativas. Resultados Um total de 75% dos pacientes com ELA apresentou resultados de TRODAT abaixo dos níveis considerados normais; 25% no grupo controle sem doença neurodegenerativa e 100% no grupo DP. Uma diferença estatisticamente significativa foi encontrada entre os pacientes com ELA e o grupo controle sem doença neurodegenerativa nos valores de TRODAT p< 0,05. Conclusões Nosso estudo está de acordo com as evidências neuropatológicas e funcionais que demonstram a existência de disfunção nigroestriatal em pacientes com ELA. Mais pesquisas para entender melhor o papel dessas mudanças no processo fisiopatológico da ELA precisam ser realizadas.

INOCA: Evaluación no invasiva de los mecanismos fisiopatológicos mediante CZT-SPECT / INOCA: Non-Invasive Assessment of the Pathophysological Mechanisms Using CZT-SPECT

RESUMEN Introducción: Una de las causas propuestas del síndrome INOCA (por sus siglas en inglés: Ischemia with Non-Obstructive Coronary Arteries) es la disfunción microvascular (DMV), la cual puede evaluarse en forma no invasiva, mediante la cuantificación del flujo sanguíneo miocárdico (FSM) y la reserva de flujo miocárdica (RFM). Las imágenes de perfusión miocárdica (IPM) y dinámicas con CZT-SPECT en reposo - dipiridamol - y prueba de frio (PF), permiten establecer la presencia de DMV evaluando diferentes mecanismos fisiopatológicos: endotelio independiente o dependiente, respectivamente. Objetivos: Evaluar la utilidad de CZT-SPECT en el diagnóstico de DMV y los diferentes mecanismos patológicos involucrados, en pacientes con diagnóstico de INOCA. Material y métodos: Se incluyeron en forma prospectiva 93 pacientes consecutivos con diagnóstico de INOCA, a los que se les realizó IPM e imágenes dinámicas con CZT-SPECT en reposo-dipiridamol-PF. El FSM se cuantificó con el software 4DM. Se consideró respuesta anormal al dipiridamol una RFM menor a 2 y a la variación del FSM (∆FSM) menor a 1,5 con PF. Se definió DMV a la presencia de una o ambas respuestas anormales. Resultados: El CZT-SPECT detectó DMV en un 85% (n=79) de los pacientes con INOCA. El 42% tuvo respuesta anormal con ambos apremios mientras que el 43% restante, mostró una respuesta alterada del FSM sólo con PF. Conclusiones: El uso de CZT-SPECT empleando ambos apremios, permitió evaluar diferentes mecanismos fisiopatológicos que causan DMV presente en la mayoría de los pacientes con INOCA.

ABSTRACT Background: One of the causes of INOCA (Ischemia with Non- Obstructive Coronary Arteries) is microvascular dysfunction (MVD), which can be noninvasively assessed through the quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR). Dynamic myocardial perfusion imaging (MPI) by CZT-SPECT at rest, with dipyridamole stress test and cold pressor test (CPT) can establish the presence of two different pathophysiological mechanisms of MVD: endothelium-independent or endothelium-dependent, respectively. Objectives: The aim of this study was to evaluate the usefulness of CZT-SPECT for the diagnosis of MVD and the different mechanisms involved in patients with INOCA. Materials and Methods : A total of 93 consecutive INOCA patients were prospectively included and underwent dynamic MPI with CZT-SPECT at rest and with dipyridamole stress test and CPT. THe MBF was quantified using 4DM® software. A MFR response to dipyridamole <2, and changes in MBF (∆MBF) <1.5 with CPT were considered abnormal responses. MVD was defined in the presence of one abnormal response or both. Results: CZT-SPECT detected MVD in 85% (n=79) of the patients with INOCA. Forty-two percent had an abnormal response to both stressors while 43% presented an abnormal response of MBF only with CPT. Conclusion: The use of CZT-SPECT with both stress tests allowed the evaluation of different possible pathophysiological mechanisms of MVD present in most patients with INOCA.

Seguimiento no invasivo del tratamiento ajustado en pacientes con angina microvascular / Non-invasive follow-up of adjusted treatment in patients with microvascular angina

Resumen Actualmente existen múltiples métodos invasivos y no invasivos que pueden emplearse para establecer el diagnóstico de disfunción microvascular (DMV) en pacientes con INOCA (por sus siglas en inglés: Ischemia with Non-Obstructive Coronary Arteries) y angina microvascular (AMV). No obstante, todavía no contamos con un enfoque de tratamiento específico para este grupo de pacientes. La tendencia act ual es ajustar el tratamiento al mecanismo fisiopatológico implicado, añadiendo antagonistas del calcio en aquellos pacientes en los que se demuestre disfunción endotelial, o bien bloqueadores beta en aquellos que presenten disfunción músculo liso dependiente. Presentamos tres casos clínicos de INOCA con sospecha de AMV. A dos de ellos se les realizó diagnóstico no invasivo de DMV mediante CZT-SPECT, utilizando como apremio dipiridamol para evaluar el mecanismo músculo liso dependiente y test de frío para evaluar el mecanismo endotelio dependiente. Según los resultados obtenidos se ajustó el tratamiento, se realizó seguimiento clínico y valoración de la angina por la escala de Seattle, con nueva valoración de la función microvascular a los 6 meses. El tercer caso clínico, en cambio, es una paciente que inició tratamiento empírico para ambos mecanismos y posteriormente abandonó el tratamiento instaurado, evaluándose la función microvascular bajo tratamiento farmacológico y sin el mismo.

Abstract There are currently multiple invasive and non-invasive methods that can be used to establish the diagnosis of microvascular dysfunction (MVD) in patients with INOCA (Ischemia with Non-Obstructive Coronary Arteries) and microvascular angina. However, we still do not have a specific treatment approach for this group of patients. The current trend is to adjust the treatment to the pathophysiological mechanism involved, adding calcium blockers in those patients where endothelial dysfunction is demonstrated or beta blockers in those patients who present smooth muscle-dependent dysfunction. We present three clinical cases of INOCA with suspected microvascular angina. Two of them underwent a non-invasive diagnosis of MVD by CZT-SPECT, using dipyridamole to evaluate the smooth muscle-dependent mechanism and cold pressor test to evaluate the endothelium-dependent mecha nism. According to the results obtained, the treatment was adju sted, clinical follow-up was carried out and angina was assessed using the Seattle scale, with a new microcirculation assessment at 6 months. The third clinical case, on the other hand, was a patient who began empirical treatment for both mechanisms and subsequently abandoned the established treatment. Microvascular function was evaluated under pharmacological treatment and without it.

Análisis de los riesgos radiológicos en la medicina nuclear diagnóstica del Instituto de Hematología e Inmunología de Cuba / Analysis of radiological risks in diagnostic nuclear medicine of the Institute of Hematology and Immunology of Cuba

Introducción: Para el inicio de las operaciones en el servicio de medicina nuclear del Instituto de Hematología e Inmunología, se realizó el análisis de los riesgos radiológicos. Objetivos: Determinar la contribución individual de las etapas del proceso y de los elementos de control en el riesgo radiológico. Métodos: Se desarrolló el modelo del proceso a partir del método de la matriz de riesgo. Las medidas que se adicionaron estuvieron dirigidas a eliminar las secuencias accidentales con riesgo de nivel medio y consecuencias altas para los pacientes. Se determinaron los elementos de control más importantes por su participación porcentual e incidencia en el cambio del nivel de riesgo al ser eliminados. Resultados: Las etapas más contribuyentes al riesgo fueron por orden de importancia; la preparación de radiofármacos, la adquisición de las imágenes y la administración. Se destacan las medidas siguientes: carga de trabajo moderada, capacitaciones al oficial de protección radiológica y al que realiza las administraciones, el procedimiento de contrastar los datos de la dosis que será administrada al paciente con lo establecido en la prescripción del estudio, las pruebas de control de calidad de radiofármacos, el análisis de los resultados de la dosimetría realizada periódicamente a los trabajadores y las auditorías externas e internas con equipamiento diferente. Conclusiones: Se incluyeron todas las medidas identificadas en la obtención del riesgo residual y en el análisis de sensibilidad en el Plan de mejora de la seguridad y calidad, como garantía de la seguridad radiológica de las operaciones(AU)

Introduction: For the start of operations in the nuclear medicine service of the Institute of Hematology and Immunology, the analysis of radiological risks carried out. Objectives: To determine the individual contribution of the stages of the process and of the control elements in the radiological risk. Methods: The developed process model was from the risk matrix method. The added measures were at eliminating accidental sequences with medium risk and high consequences for the patients. The most important control elements were by their percentage participation and incidence in the change in the level of risk when they eliminated. Results: The stages most contributing to the risk were, in order of importance, the preparation of the radiopharmaceuticals, the acquisition of the images and the administration. Highlighted measures are the following: a moderate workload, the training for the radiation protection officer and the one who performs the administrations and the procedure of contrasting the data of the dose that will administer to the patient against what is in the study prescription. Besides are the tests quality control of radiopharmaceuticals, the analysis of the results of the dosimetry performed on the workers periodically and the external and internal audits with different equipment. Conclusions: All the measures identified in obtaining the residual risk and in the sensitivity analysis, were included in the Safety and Quality Improvement Plan, as a guarantee of the radiological safety of the operations(AU)

Application effect of MOOC+CBL teaching mode in practice teaching of nuclear medicine SPECT/CT / 中华医学教育探索杂志

Objective:To explore the application effect of massive online open course (MOOC) + case-based learning (CBL) in SPECT/CT practice teaching of nuclear medicine.Methods:Twenty-nine interns of nuclear medicine SPECT/CT in Xiaogan Hospital Affiliated to Wuhan University of Science and Technology from January 2020 to October 2020 were selected as the research group and received MOOC + CBL teaching. Taking 31 interns from January 2019 to October 2019 as the control group, and the traditional teaching method was conducted. At the end of the internship, the students' theoretical and operational skills were assessed. Their learning motivation and thinking ability were evaluated by using the study process questionnaire (SPQ) and the Chinese version of California critical thinking disposition inventory (CTDI-CV), and the two groups' satisfaction with teaching was compared. SPSS 22.0 was used for Chi-square test and t-test. Results:The results of theoretical knowledge, PET/CT case analysis and image diagnosis in the study group were higher than those in the control group ( P<0.05). The total scores of surface motivation, deep motivation and SPQ in the study group were higher than those in the control group ( P<0.05). The self-confidence scores of open mind, analytical ability, systematization ability, and critical thinking and CTDI-CV total scores of the study group were higher than those of the control group ( P<0.05). The study group was more satisfied with the teaching and the enhancement of self-study ability than the control group ( P<0.05). Conclusion:MOOC + CBL teaching for nuclear medicine SPECT/CT interns can improve their examination results, learning motivation and thinking ability, and also enhance their self-study ability.

Comparison results of image analysis software for quality control of SPECT equipment / 中国辐射卫生

@#<b>Objective</b> To investigate the differences in output results between difference analysis software, and to provide a reference for the improvement of quality control and the standard revision of SPECT equipment. <b>Methods</b> The image analysis software for quality control held by 14 radiological health technical service institutions was selected as the research subjects using the cluster sampling method. The results of the comparison were analyzed and evaluated according to the Z-score method with certified reference values. <b>Results</b> In the comparison items of “intrinsic uniformity” and “intrinsic spatial linearity”, the number of software with suspicious, deviated and incorrect results accounted for a relatively high proportion, while the results of other comparison items were satisfactory. <b>Conclusion</b> The applicability of SPECT image analysis software lacks effective supervision measures. Relevant departments should introduce feasible measures to standardize the software production and update process, accelerate the construction of radiological health information reporting platform, and promote the healthy development of the radiation health testing industry.

Correlación de sincronía de la contracción del ventrículo izquierdo con función sisto-diastólica, masa y excentricidad en diversas afecciones cardíacas mediante un software comercial dedicado de SPECT gatillado / Gated Spect evaluation of ventricular systolic synchrony: correlation with ventricular mass and excentricity in different forms of cardiac disease

INTRODUCCIÓN: Actualmente, hay nuevas herramientas de software disponibles para medir la sincronía de la contracción intraventricular izquierda mediante SPECT de perfusión miocárdica. Esta técnica permite identificar anomalías de la conducción, apoyar la terapia de resincronización en insuficiencia cardíaca refractaria e incluso la detección precoz de isquemia. OBJETIVO: Conocer la correlación de la sincronía de contracción con otros parámetros de disfunción sisto-diastólica ventricular izquierda. MÉTODO: Estudiamos 135 pacientes remitidos para pesquisa o evaluación de enfermedad coronaria conocida mediante SPECT gatillado. La evaluación de la interpretación inicial con programas QPS/QGS® visual y cuantitativo se efectuó a 50 casos con defectos de perfusión transitoria de diversos tamaños (isquemia), 25 de tipo fijo o mixto (infarto) y 60 sin ellos (normal). Los volúmenes telesistólicos oscilaron entre 26 y 458 mL. Se excluyeron casos con arritmias, anomalías de conducción y artefactos (actividad o movimiento extracardiaco). Los SPECT se procesaron retrospectivamente utilizando el programa Emory Synctool®. Del histograma de sincronía de la contracción, el ancho de banda (BW) y la desviación estándar (SD) se correlacionaron con la fracción de eyección (FEVI), volúmenes y excentricidades sistólico / diastólico, masa ventricular izquierda, tasa máxima de llenado (PFR) y tiempo al máximo de llenado (TPFR). RESULTADOS: Los BW y SD del histograma de fase de contracción fueron mayores en el grupo con defectos fijos y mixtos en comparación con los con perfusión normal. Las correlaciones en reposo y post estrés (Spearman) entre SD y BW con FEVI, volúmenes, excentricidad y masa fueron significativas (p <0,0002) salvo TPFR que no fue significativa. CONCLUSIÓN: La sincronía de contracción intraventricular sistólica izquierda medida con SPECT se correlaciona excelentemente con los parámetros funcionales sistólicos y diastólicos, así como con masa y excentricidad en diversas condiciones y tamaños cardíacos.

INTRODUCTION: New software tools are available to measure left intraventricular contraction synchrony by myocardial perfusion SPECT. This technique allows identification of conduction abnormalities, support resynchronization therapy in refractory heart failure and even allows early detection of myocardial ischemia. OBJECTIVE: To determine the correlation of systolic synchrony with other parameters of left ventricular systolic-diastolic dysfunction. METHODS: We studied 135 patients referred for screening or known coronary artery disease evaluation by triggered SPECT. Evaluation of the initial interpretation with visual and quantitative QPS/QGS® programs was performed in 50 patients with transient perfusion defects of various sizes (ischemia), 25 of fixed or mixed type (infarction) and 60 without abnormalities. Telesystolic volumes ranged from 26 to 458 mL. Cases with arrhythmias, conduction abnormalities and artifacts (extracardiac activity or motion) were excluded. SPECT scans were retrospectively processed using the Emory Synctool® software. Histograms of systolic contraction synchrony bandwidth (BW) and standard deviation (SD) were correlated with ejection fraction (LVEF), systolic/diastolic volumes and eccentricities, left ventricular mass, peak filling rate (PFR) and time to maximum filling (TPFR). RESULTS: BW and SD of the contraction pase histogram were higher in the fixed and mixed defect group compared to studies showing normal perfusion. Spearman correlations at rest and poststress between SD and BW with LVEF, volumes, eccentricity and mass were all significant (p<0.0002) except for TPFR. CONCLUSION: Left systolic intraventricular contraction synchrony measured with SPECT presents an excellent correlation with systolic and diastolic functional parameters, as well as with mass and eccentricity in various cardiac conditions and ventricular dimensions.

Psychiatric neuroimaging research in Brazil: historical overview, current challenges, and future opportunities

The last four decades have witnessed tremendous growth in research studies applying neuroimaging methods to evaluate pathophysiological and treatment aspects of psychiatric disorders around the world. This article provides a brief history of psychiatric neuroimaging research in Brazil, including quantitative information about the growth of this field in the country over the past 20 years. Also described are the various methodologies used, the wealth of scientific questions investigated, and the strength of international collaborations established. Finally, examples of the many methodological advances that have emerged in the field of in vivo neuroimaging are provided, with discussion of the challenges faced by psychiatric research groups in Brazil, a country of limited resources, to continue incorporating such innovations to generate novel scientific data of local and global relevance.

Estimation of renal absorbed doses in the treatment of neuroendocrine tumors using 177Lu-DOTA-TATE / 中华放射医学与防护杂志

Objective:To estimate the renal absorbed dose in the treatment of neuroendocrine tumors using 177Lu-DOTA-TATE and to assess the radiation safety and guide the treatment. Methods:The dosimetric calculations of patients treated with 177Lu-DOTA-TATE were carried out based on planar images of single photon emission computed tomography (SPECT). The regions of interest (ROIs) of the whole body and kidneys were delineated and converted into activity. Accordingly, the time-activity curves of the ROIs were obtained. The effective half-lives and cumulative activity of ROIs were calculated through the fitting of a single exponential equation of the ROIs. Then the absorbed doses were calculated based on the medical internal radiation dosimetry (MIRD) formalism. Results:A total of 11 patients with neuroendocrine tumors received 18 cycles of treatments with 177Lu-DOTA-TATE. The effective half-lives of 177Lu-DOTA-TATE in the whole body and kidneys were 20.0-99.8 h and 38.2-75.2 h, respectively, with an average of (57.3 ± 21.4) h and (53.1 ± 12.5) h, respectively. The renal absorbed doses of 177Lu-DTA-TATE were 0.25-1.48 mGy/MBq, with an average of (0.90 ± 0.31) mGy/MBq. The minimum and maximum renal absorbed doses in a single treatment cycle were 1.8 Gy and 9.6 Gy, respectively, while the maximum renal absorbed dose in multiple treatment cycles was 21.7 Gy. Conclusions:The renal absorbed doses in the treatment of neuroendocrine tumors using 177Lu-DOTA-TATE were estimated. The result indicate that the renal absorbed doses were lower than the tolerable dose limits. This study is expected to guide the precise treatment of neuroendocrine tumors.

Osteofibrous Dysplasia-like Adamantinoma Mimicking Bone Metastasis in a Patient With Rectosigmoid Cancer

@#A patient with underlying rectosigmoid cancer presented with solitary bone lesion at left tibia. Eventhough, solitary bone metastasis particularly in the appendicular skeleton is rare in rectosigmoid cancer, it remained as the most likely initial diagnosis. However, after further characterisation by various imaging modalities and subsequent biopsy, the lesion proved to be an osteofibrous dysplasia like-adamantinoma (OFD-like adamantinoma), which is a subtype of adamantinoma. Being a rare primary bone tumour, adamantinoma and its subtypes are infrequently thought of in the initial working diagnosis of a patient with known malignancy who presents with solitary bone lesion. We present here a case of OFD-like adamantinoma in a patient with underlying rectosigmoid cancer, which mimic a metastastic bone lesion.

Accuracy of Choline PET/CT vs. Tc 99m Sestamibi SPECT/CT parathyroid imaging in comparison to histopathology in the diagnosis of parathyroid adenoma : A meta-analysis

Introduction@#In the advent of the recently accepted use of Choline in parathyroid PET/CT, we aimed to assess its accuracy in diagnosing parathyroid adenomas in comparison to the Tc 99m Sestamibi SPECT/CT parathyroid imaging, with histopathology as the reference standard.@*Objective@#To determine the diagnostic accuracy of Choline PET/CT in comparison to Tc 99m Sestamibi parathyroid imaging in detecting parathyroid adenomas, with histopathology as the reference standard. @*Methods@#Cross-sectional studies from 2014 to 2019 were identified through MEDLINE, Pubmed, clinicaltrials.gov, and Google scholar. Our literature search yielded 13 articles, of which only 3 met the set inclusion and exclusion criteria.@*Results@#Three published cross-sectional studies were included with a total of population of 157 patients. Choline PET/CT was found to have a pooled sensitivity of 0.99 (0.96 - 1.00), pooled specificity of 0.45 (0.17 - 0.77), positive likelihood ratio of 1.79 (1.1 – 2.9), negative likelihood ratio of 0.03 (0.0 – 0.1), positive predictive value of 96.0% (93.4 - 97.7%) and negative predictive value of 83.3% (39.0 - 97.6%), estimated with 95% CI. Tc 99m Sestamibi SPECT/CT parathyroid imaging had a pooled sensitivity of 0.77 (0.70-0.84), pooled specificity of 0.45 (0.17 - 0.77), positive likelihood ratio of 1.43 (0.8–2.4), negative likelihood ratio of 0.49 (0.2–1.4), positive predictive value of 96.0% (93.4-97.7%) and negative predictive value of 83.3% (39.0-97.6%), estimated with 95% CI@*Conclusion@#Choline PET/CT showed superior sensitivity, negative predictive value and negative likelihood ratio over Tc 99m Sestamibi SPECT/CT parathyroid imaging. The measured specificities, positive predictive values and positive likelihood ratios of both modalities were found to be similar.

Perfil clínico, epidemiológico y descripción de los resultados de la Tomografía ósea computarizada con emisión simple de fotones (SPECT) en pacientes con dolor de cuello y espalda. Estudio de cohorte transversal / Clinical and epidemiological profile and description of the results of bone single photon emission computed tomography (SPECT) in patients with neck and back pain: Cross-sectional study

Introducción La tomografía ósea computarizada (TAC) con emisión simple de fotones (SPECT: single photon emission computed tomography) es una herramienta diagnóstica importante en los pacientes con dolor de cuello y espalda. Es una prueba funcional que se adelanta a los cambios estructurales en algunas patologías de columna. El objetivo del estudio es definir el perfil epidemiológico de pacientes con dolor axial crónico y/o subagudo en la columna vertebral. Materiales y Métodos Serie de casos cuyo objetivo general es presentar las características clínicas y sociodemográficas, así como los resultados de TAC con SPECT de los pacientes que consultaron al Hospital en un periodo de tiempo con diagnóstico de dolor de cuello o espalda y se les solicitó dicho examen. Resultados 77 pacientes cumplieron los criterios de inclusión, La mediana para la edad fue de 48 años, 57.1% eran hombres y 42.9% mujeres. 57 pacientes tenían localización única del dolor (74%) y 20 pacientes tenían localización múltiple (26%), los segmentos afectados fueron 57 lumbar (74%), cervical 15 (19.5%) y sacro 1 (1.3%). La impresión diagnóstica preexamen más común fue enfermedad facetaría en 25 casos para un 32.5%. En cuanto a los resultados del SPECT el radiofármaco captó en 48 ocasiones (62.3%) y los sitios en que captó el radiofármaco se distribuyeron así: facetas 13 (16.9%), cuerpo vertebral 28 (36.4%), Pars Interarticularis 3 (3.8%), disco intervertebral 1 (1.3%), 3 (3.8%) captaron en sitios diferentes al raquis, El índice de concordancia diagnóstica luego del SPECT se dio en 33 casos (42.85%). Discusión La mayoría de las gammagrafías con captación fueron en los cuerpos vertebrales, en el contexto de nuestro hospital como centro de trauma y que muchos de los pacientes tenían dolor secundario a accidentes de tránsito o accidentes laborales, se correlacionan con microfracturas o contusiones óseas. La gammagrafía con SPECT sigue siendo una prueba funcional que nos puede ayudar en el diagnóstico, pronóstico y enfoque terapéutico de los pacientes con dolor raquídeo axial en sus diferentes estadios.

Background SPECT bone scan with is an important diagnostic tool in patients with neck and back pain. It is a functional test that anticipates structural changes in some spinal pathologies. Aim of study is to define the epidemiological profile of patients with chronic and/or subacute axial spine pain. Methods A retrospective descriptive study whose general objective is to present the clinical and sociodemographic characteristics, as well as the results of the SPECT scans of the patients who visited the Hospital in a period of time with a diagnosis of neck or back pain and were requested such an examination. Results Seventy-seven patients met the inclusion criteria. The median age was 48 years, 57.1% were men and 42.9% were women. Fifty-seven patients had a single location of pain (74%) and 20 patients had multiple location (26%), the affected segments were 57 lumbar (74%), cervical 15 (19.5%) and sacrum 1 (1.3%). The most common pre-examination diagnostic impression was facet disease in 25 cases for 32.5%. Regarding the SPECT results, the radiopharmaceutical captured on 48 occasions (62.3%) and the sites where it captured the radiopharmaceutical were distributed as follows: facets 13 (16.9%), vertebral body 28 (36.4%), pars interarticularis 3 (3.8%).), intervertebral disc 1 (1.3%), 3 (3.8%) captured in sites other than the spine. The diagnostic concordance index after SPECT occurred in 33 cases (42.85%). Discussion Most of the uptake scans were in the vertebral bodies, beneath the context of our hospital, as a trauma center, and that many of the patients had pain secondary to traffic accidents or work behavior accidents, they are correlated with micro-fractures or bone contusions. SPECT scintigraphy continues to be a functional test that can help us in the diagnosis, prognosis and therapeutic approach of patients with axial spinal pain in its different stages.

Aporte de las imágenes híbridas spect/ct para el diagnóstico diferencial de lesiones óseas malignas y benignas en pacientes con cáncer de mama. Nuestra experiencia / Contribution of the spect/ct hybrid images for the differential diagnosis of malignant and benign bone lesions in patients with breast cancer. Our experience

Objetivo El objetivo del presente trabajo es evaluar el valor adicional del spect/ct sobre el Centellograma de Cuerpo Entero (cce) y la spect en pacientes con cáncer de mama con mínimo dos estudios: tiempo inicial (i) y evolución (e). Material y método Se evaluaron retrospectivamente 208 lesiones en 186 pacientes. Se realizaron imágenes: cce, spect y spect/ct del esqueleto axial con 99mTcmdp y equipo híbrido Infinia Hawkeye 4 GE. Las lesiones se caracterizaron del siguiente modo: benigna (b); maligna (m); y equívocas: probablemente benigna (pb) y probablemente maligna (pm). Resultados spect/cti clasificó 197/208 lesiones (94,7%), specti 155/208 (74,5%) y ccei 130/208 (51%). Los tres métodos coincidieron inicialmente en 138 lesiones: 106 b (77%), 23 m (17%) y 9 equívocas (6%), y en la evolución en 155: 110 b (71%), 44 m (28%), 1 equívoca (1%). La sensibilidad, especificidad y exactitud inicial para diagnóstico de metástasis (incluyendo como malignas las lesiones probablemente malignas) fueron 92/70/51% (ccei), 100/78/75% (specti) y 100/97/95% (spect/cti). Diferencias de a pares: ccei vs specti y spect/cti para sensibilidad (p<0,05) y specti y ccei vs spect/cti especificidad y exactitud (p<0,001). Conclusiones El aporte de spect/ct incrementó la precisión y certeza diagnóstica para diferenciar las lesiones benignas, malignas y equívocas. Su utilización debería ser rutinaria en la detección de metástasis óseas en pacientes con carcinoma de mama

Objective To assess the additional value of spect/ct on whole-body scintigraphy (wbs) and spect in patients with breast cancer, with a minimum of two tests: start time (i) and assessment (e). Materials and method Retrospective assessment of 208 lesions in 186 patients. Images were taken by wbs, spect and spect/ct of the axial skeleton with 99mTc- mdp and hybrid equipment Infinia Hawkeye 4 GE. Characterization of the lesions: benign (b), malignant (m) and equivocal: likely to be benign or malignant. Results By using spect/cti, 197/208 lesions (94.7%), specti 155/208 (74.5%) and wbsi 130/208 (51%) were classified. The three methods initially coincided on 138 lesions: 106 b (77%), 23 m (17%) and 9 equivocal (6%); and on assessment on 155: 110 b (71%), 44 m (28%), 1 equivocal (1%). The initial sensitivity, specificity and accuracy for the diagnosis of metastases (including as malignant those lesions which were likely to be so) were as follows: 92/70/51% (wbsi), 100/78/75% (specti) and 100/97/95% (spect/cti). Differences by pairs: wbsi vs specti and spect/cti for sensitivity (p<0,05) and specti and wbsi vs spect/cti for specificity and accuracy (p<0,001). On assessment 99%. Conclusions The contribution of spect/ct has increased diagnostic accuracy and certainty to differentiate benign, malignant and equivocal lesions. It should be used routinely for the detection of bone metastases in patients with breast cancer

SPECT-CT in Differentiating Metastatic and Degenerative Lesions of the Spine

@#Introduction: The purpose of this study was to determine the usefulness of SPECT-CT in differentiating metastatic and degenerative disease of the spine. Methods: Twenty-eight patients aged 50 years and above diagnosed with various cancers were referred for whole body (WB) planar bone scintigraphy. Those with a maximum three foci of tracer uptake in the spine were selected for the study. SPECT-CT of these areas of uptake was performed and the lesions were classified as degenerative, indeterminate or metastasis. A repeat study (WB planar bone scintigraphy and SPECT-CT) was performed between 3 to 12 months later. These areas of uptake were reassessed and compared with the first WB planar bone scintigraphy and SPECT-CT. The second SPECT-CT was used as the standard for the diagnosis. Results: Thirty-seven lesions in 28 patients were assessed. The sensitivity of the first WB planar bone scintigraphy, second WB planar bone scintigraphy and first SPECT-CT is 75%, 62.5% and 75% respectively. The specificity of the first WB planar bone scintigraphy, second WB planar bone scintigraphy and first SPECT-CT is 86%, 93%, 90% respectively. There was 2.7% of ‘indeterminate lesion’ in the first WB planar bone scintigraphy, 5.4% in the second WB planar bone scintigraphy, and 5.4% in the first SPECT-CT. The indeterminate lesions were resolved in the second SPECT-CT. Conclusion: SPECT- CT is useful in differentiating degenerative disease from metastatic lesions in the spine.

Diagnosis of pulmonary embolism: A comparison between ventilation/perfusion SPECT/CT and perfusion-only SPECT/CT

@#Background: The role of nuclear medicine in diagnosing pulmonary embolism (PE) is continuously evolving owing to advancements in imaging methods. In recent years, ventilation/perfusion single photon emission computed tomography-computed tomography (V/Q SPECT/CT) has established a synergistic role over conventional V/Q planar scintigraphy and V/Q SPECT in diagnosing pulmonary embolism. Objectives: In this study, we aimed to assess the incremental value of V/Q SPECT/CT over conventional V/Q planar scintigraphy and V/Q SPECT, and to determine if Q only-SPECT/CT without the conventional ventilation component could replace the current imaging protocol in diagnosing pulmonary embolism. Methods: We retrospectively assessed 73 patients with suspicion of pulmonary embolism who had undergone/Q planar scintigraphy, V/Q SPECT and V/Q SPECT/CT consecutively. Combination of clinical follow-up, laboratory test results and correlative imaging were used as reference standard. Q-only SPECT/CT datasets were then analysed separately without the V-planar, V-SPECT and V-SPECT/CT datasets. Results: A total of 66 patients fulfilled our initial inclusion and exclusion criteria, with 23 patients as positive for PE and 43 patients ruled out of having PE based on the reference standard. Sensitivity and specificity for V/P planar scintigraphy, V/Q SPECT, and V/Q SPECT-CT were 86.9% and 39.5%, 91.3% and 55.8%, and 100% and 97.6% respectively. Overall, SPECT/CT resulted in significantly higher diagnostic accuracy than planar and SPECT imaging respectively (p<0.05). Q-only SPECT/CT significantly over diagnosed pulmonary embolism in 12 patients (p<0.05). Conclusion: Adding V/Q SPECT/CT to the algorithm of PE significantly improves the sensitivity and specificity. However, by eliminating the ventilation component, the diagnostic accuracy is significantly reduced.

Cell labeling and tracking imaging in vivo: Newest advance in animals and humans / 中国组织工程研究

BACKGROUND: Various cell therapy products have been approved by clinical trials worldwide, and cell therapies such as stem cell therapy and adoptive immunotherapy have attracted much attention. Real-time observation and imaging in vivo can visualize the distribution of cells, track cell movement, monitor cell viability, and observe the cell migration and growth. Many imaging technologies can visualize cells in vivo, such as ultrasound, optics, MRI and nuclear imaging, and these methods need to correspond to different labeling and detection strategies. Each strategy has its own advantages and disadvantages. OBJECTIVE: To review the principle and development of different tracking methods, and their application in animals and humans. METHODS: PubMed, Google Scholar, Web of Science and CNKI databases were searched with the keywords of “cell tracking, in vivo cell tracking, PET imaging, MRI, optical imaging.” The articles published in the past 5-10 years were preferred. The contents of the articles mainly describe the principle of different tracking methods, and their application in animal models and patients. RESULTS AND CONCLUSION: In the past 20 years, cell tracking has developed into a multifarious discipline, not only establishing a variety of robust methods in animal models, but also proving the feasibility of clinical transformation in some human studies. The development of the non-invasive detection methods, such as PET and MRI, and new contrast agents provides strong support for the application of cell therapy in clinical and scientific researches.