El dilema clínico frente a los pacientes con ergometría positiva y prueba de perfusión miocárdica con SPECT normal / The clinical dilemma facing patients with positive stress test and normal SPECT myocardial perfusion imaging

La evaluación de la perfusión miocárdica con SPECT combina una prueba de esfuerzo (ergometría o estrés farmacológico) junto a imágenes de perfusión con radioisótopos. Este estudio es útil para establecer el diagnóstico de enfermedad arterial coronaria, estratificar el riesgo de infarto y tomar decisiones terapéuticas. Un resultado normal aporta un alto valor predictivo negativo, es decir, una muy baja probabilidad de que el paciente presente eventos cardiovasculares. El hallazgo de signos de isquemia en la ergometría podría poner en jaque el valor predictivo negativo de una perfusión normal. En presencia de este resultado, el paso siguiente es evaluar los predictores de riesgo en la ergometría, el riesgo propio del paciente en función de los antecedentes clínicos y el puntaje cálcico coronario, cuando este se encuentra disponible. Ante la presencia concomitante de otros marcadores de riesgo se sugiere completar la evaluación con un estudio anatómico.El uso de nuevas tecnologías podría mejorar la precisión en la predicción de eventos. (AU)

Assessment of myocardial perfusion with SPECT combines a stress test (ergometry or pharmacological stress) with radioisotope perfusion imaging. This test is helpful to diagnose coronary artery disease, stratify the risk of heart attack, and make therapeutic decisions. A normal result provides a high negative predictive value; therefore, the probability of cardiovascular events is very low. Signs of ischemia on an ergometry could jeopardize the negative predictive value of normal perfusion. In this clinical setting, the next step is to evaluate the risk predictors in the stress test, the individual risk based on the clinical history, and the coronary calcium score when available. Given the simultaneous presence of other risk markers,completing the evaluation with an anatomical study is suggested. The use of new technologies could improve the accuracy of event prediction. (AU)

Validation of automated image co-registration integrated into in-house software for voxel-based internal dosimetry on single-photon emission computed tomography images / Validação do corregistro automático de imagem integrado a software de análise de dosimetria interna baseada em voxel para tomografia computadorizada de emissão de fóton único

Abstract Objective: To develop an automated co-registration system and test its performance, with and without a fiducial marker, on single-photon emission computed tomography (SPECT) images. Materials and Methods: Three SPECT/CT scans were acquired for each rotation of a Jaszczak phantom (to 0°, 5°, and 10° in relation to the bed axis), with and without a fiducial marker. Two rigid co-registration software packages-SPM12 and NMDose-coreg-were employed, and the percent root mean square error (%RMSE) was calculated in order to assess the quality of the co-registrations. Uniformity, contrast, and resolution were measured before and after co-registration. The NMDose-coreg software was employed to calculate the renal doses in 12 patients treated with 177Lu-DOTATATE, and we compared those with the values obtained with the Organ Level INternal Dose Assessment for EXponential Modeling (OLINDA/EXM) software. Results: The use of a fiducial marker had no significant effect on the quality of co-registration on SPECT images, as measured by %RMSE (p = 0.40). After co-registration, uniformity, contrast, and resolution did not differ between the images acquired with fiducial markers and those acquired without. Preliminary clinical application showed mean total processing times of 9 ± 3 min/patient for NMDose-coreg and 64 ± 10 min/patient for OLINDA/EXM, with a strong correlation between the two, despite the lower renal doses obtained with NMDose-coreg. Conclusion: The use of NMDose-coreg allows fast co-registration of SPECT images, with no loss of uniformity, contrast, or resolution. The use of a fiducial marker does not appear to increase the accuracy of co-registration on phantoms.

Resumo Objetivo: Desenvolver corregistro automático e testar seu desempenho com ou sem marcador fiducial em imagens de tomografia computadorizada de emissão de fóton único (SPECT). Materiais e Métodos: Três SPECT/CTs foram adquiridas para cada rotação de um simulador de Jaszczak em relação ao eixo da maca (0°, 5° e 10°), com e sem fiducial. Dois métodos de corregistro inelástico foram aplicados - SPM12 e NMDose-coreg -, e a porcentagem do erro quadrático médio (%RMSE) foi usada para analisar a qualidade do corregistro. Uniformidade, contraste e resolução foram medidos antes e após o corregistro. NMDose com corregistro automático foi usado para calcular a dose renal de 12 pacientes tratados com 177Lu-DOTATATE e comparado com OLINDA/EXM. Resultados: A marcação fiducial não modificou a qualidade do corregistro das imagens SPECT, medida pela %RMSE (p = 0,40). Não houve impacto na uniformidade, contraste e resolução após o corregistro de imagens adquiridas com ou sem fiduciais. Aplicação clínica preliminar mostrou tempo total de processamento de 9 ± 3 min/paciente para NMDose e 64 ± 10 min/paciente para OLINDA/EXM, com alta correlação entre ambos, apesar de menor dose renal em NMDose. Conclusão: NMDose-coreg permite o corregistro rápido de imagens SPECT, sem perda de uniformidade, contraste ou resolução. O uso da marcação fiducial não aumentou a precisão do corregistro em fantomas.

Ambient dose equivalent in 99mTcO4- single photon emission computed tomography of the thyroid among patients with hyperthyroidism / 预防医学

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.

Parotid duct anastomosis with an epidural catheter as a stent and evaluation of postoperative gland function / 口腔疾病防治

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.

Crossed aphasia in a left-handed patient with non-fluent variant of primary progressive aphasia with left asymmetric brain SPECT / Afasia cruzada em paciente canhota com afasia progressiva primária variante não fluente com SPECT cerebral assimétrico à esquerda

ABSTRACT Primary progressive aphasia is a clinical syndrome caused by neurodegeneration of areas and neural networks involved in language, usually in the left hemisphere. The term "crossed aphasia" denotes an acquired language dysfunction caused by a lesion in the ipsilateral hemisphere to the dominant hand. Objective: To describe a case of crossed aphasia in a 60-year-old left-handed patient with a non-fluent variant of primary progressive aphasia diagnosis (age of onset=52), evidenced by a left asymmetry on brain SPECT scan. Methods: Clinical and family history, the Edinburgh Handedness Inventory, Measurement of Functional Activities in Older Adults in the Community, the "Mini-Mental State Examination", the Trail Making Test, the Tower of London, and the Neuropsychological assessment for dementia, and neuroimaging studies were carried out. Results: Neuropsychological assessment showed severe cognitive impairment, especially regarding language. The magnetic resonance imaging showed important signs of cortico-subcortical atrophy, with predominance in the frontal and temporal lobes. The single-photon emission computed tomography scan showed moderate to severe hypoperfusion in the left cerebral hemisphere, including the hippocampus. Conclusion: We described a clinical case of crossed aphasia in a left-handed woman with a non-fluent variant of primary progressive aphasia with asymmetry on brain SPECT, mainly on the left, followed up for seven years.

RESUMO A afasia progressiva primária é uma síndrome clínica causada por uma neurodegeneração de áreas e redes neurais envolvidas na linguagem, geralmente no hemisfério esquerdo. O termo "afasia cruzada" denota uma disfunção adquirida de linguagem causada por uma lesão no hemisfério ipsilateral da mão dominante. Objetivo: Relatamos um caso de afasia cruzada em uma paciente de 60 anos, canhota, com um quadro clínico de afasia progressiva primária variante não fluente (idade de início=52), evidenciada por assimetria no SPECT cerebral à esquerda. Métodos: Foram realizados para o diagnóstico do caso: história clínica e familiar, o Inventário de Dominância de Edinburgh, a Escala de Atividades Funcionais de Pfeffer, o Miniexame do Estado Mental, o Teste das Trilhas, o Teste da Torre de Londres, a Avaliação Neuropsicológica Adequada às Demências e exames de neuroimagem. Resultados: A avaliação neuropsicológica mostrou comprometimento cognitivo severo, principalmente sobre a linguagem; a ressonância magnética do crânio mostrou sinais de involução córtico-subcortical, com predominância nos lobos frontal e temporal e a cintilografia cerebral por emissão de fóton único mostrou hipoperfusão moderada a severa no hemisfério cerebral esquerdo, incluindo o hipocampo. Conclusão: Registramos um caso clínico de afasia cruzada em uma paciente canhota com afasia progressiva primária variante não fluente com assimetria no SPECT cerebral, principalmente à esquerda, seguida há sete anos.

Diagnostic Efficacy of 18F-FDG PET/CT in Detecting Bone Marrow Infiltration in Patients with Newly Diagnosed Diffuse Large B-Cell Lymphoma / 生物医学与环境科学（英文）

OBJECTIVE@#Diffuse large B-cell lymphoma (DLBCL) is often associated with bone marrow infiltration, and 2-deoxy-2-(18F) fluorodeoxyglucose positron emission tomography/computed tomography ( 18F-FDG PET/CT) has potential diagnostic significance for bone marrow infiltration in DLBCL.@*METHODS@#A total of 102 patients diagnosed with DLBCL between September 2019 and August 2022 were included. Bone marrow biopsy and 18F-FDG PET/CT examinations were performed at the time of initial diagnosis. Kappa tests were used to evaluate the agreement of 18F-FDG PET/CT with the gold standard, and the imaging features of DLBCL bone marrow infiltration on PET/CT were described.@*RESULTS@#The total detection rate of bone marrow infiltration was not significantly different between PET/CT and primary bone marrow biopsy ( P = 0.302) or between the two bone marrow biopsies ( P = 0.826). The sensitivity, specificity, and Youden index of PET/CT for the diagnosis of DLBCL bone marrow infiltration were 0.923 (95% CI, 0.759-0.979), 0.934 (95% CI, 0.855-0.972), and 0.857, respectively.@*CONCLUSION@#18F-FDG PET/CT has a comparable efficiency in the diagnosis of DLBCL bone marrow infiltration. PET/CT-guided bone marrow biopsy can reduce the misdiagnosis of DLBCL bone marrow infiltration.

Current status and prospect of preoperative assessment of heart disease risk in liver transplant recipients / 器官移植

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.

Progress in application of single-photon emission computed tomography/computed tomography (SPECT/CT) imaging in clinical practice / 中国辐射卫生

@#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.

Biograph Vision 600 PET performance testing and analysis / 中国辐射卫生

Objective To test and analyze the performance of Biograph Vision 600 PET/CT according to the NEMA NU2—2012 standard to achieve reliable, repeatable, and inter-system comparable performance measurement, and to provide a basis for future equipment stability testing and status detection. Methods The Biograph Vision PET equipment features a detector based on silicon photomultipliers, with 3.2 mm lutetium oxyorthosilicate crystals and full cover of the scintillation region. The spatial resolution, sensitivity, noise-equivalent count rate, scatter fraction, coincidence count rate, image quality, scatter correction, and time-of-flight resolution of Biograph Vision PET were tested by referring to the test model and method of the NEMA NU2—2012 standard. Results The Biograph Vision 600 PET equipment showed lateral and axial spatial resolutions of 3.69 mm and 3.81 mm at 1 cm off-center of the field of view, respectively and of 4.29 mm and 4.48 mm at 10 cm, respectively. The sensitivity was 17.5 kcps/MBq. The time-of-flight resolution changed from 210 ps to 215 ps as the count rate increased to the peak noise equivalent count rate. The NEMA peak noise-equivalent count rate was 247 kcps at 30.3 kBq/ml. The corresponding scatter fraction was 34.8%. With the NEMA module, the overall image quality contrast range was 73.6%-92.8%, and the background variability was 2.3%-6.5%; the mean lung residual error was 3.4%; and the time-of-flight resolution was 210 ps. Conclusion This performance test was performed according to the NEMA NU2—2012 standard, showing that all parameters were better than the ex-factory standard, which can provide a reference for other institutions selecting equipment and also provide a basis for future equipment stability testing and status detection.

Quantitative assessment of right ventricular myocardial blood flow with SPECT in pulmonary hypertension animal models / 中华核医学与分子影像杂志

Objective:To explore the changes of right ventricular myocardial perfusion in pulmonary arterial hypertension (PAH) pig models with a quantitative analysis technique based on dynamic SPECT myocardial perfusion imaging, and analyze the relationship between myocardial blood flow, hemodynamics and right ventricular function.Methods:Eleven Chinese miniature pigs (all males, 6-8 months old) weighing 25-30 kg were selected. The PAH models were established by ligating the main pulmonary artery and embolizing the right lower pulmonary artery. After the models were established, dynamic myocardial perfusion imaging with one-day resting/adenosine stress 99Tc m-methoxyisobutylisonitrile (MIBI) SPECT was performed, and the quantitative parameters of left and right ventricles were obtained, including stress myocardial blood flow (SMBF), rest myocardial blood flow (RMBF) and myocardial flow reserve (MFR: the ratio of stress to rest myocardial blood flow). Right heart catheterization was performed to evaluate the mean pulmonary arterial pressure (mPAP), and the right heart function index tricuspid annular plane systolic excursion (TAPSE) was measured by transthoracic echocardiography. According to TAPSE, animals were divided into right heart function preserved group ( n=5, TAPSE≥17 mm) and right heart dysfunction group ( n=4, TAPSE<17 mm). Pearson correlation analysis and the independent-sample t test were used for data analysis. Results:Nine experimental pig models were established with increased mPAP of (38.1 ± 11.6 ) mmHg (1 mmHg=0.133 kPa). Myocardial perfusion imaging showed clear radiotracer uptake in the right heart and myocardial hypertrophy. There was a significant positive correlation between right ventricular myocardial RMBF ((0.71±0.13) ml·min -1·g -1) and mPAP ( r=0.94, P< 0.001). The SMBF in the decreased right ventricular function group was significantly lower than that in the preserved right ventricular function group ((1.66±0.35) vs (2.24±0.30) ml·min -1·g -1;t=2.68, P=0.032). Conclusion:SPECT myocardial blood flow quantification can be used to evaluate the right ventricular myocardial blood flow in pig models of PAH.

Application of 99Tc m-MIBI SPECT/CT imaging in patients with primary cervical dystonia / 中华核医学与分子影像杂志

Objective:To evaluate the value of 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT/CT imaging for the identification of dystonic muscles in patients with primary cervical dystonia (PCD). Methods:A total of 10 patients with PCD (3 males, 7 females, age (47.3±9.9) years) and 10 healthy subjects (4 males, 6 females, age (43.5±9.4) years; control group) between August 2019 and October 2021 in China-Japan Friendship Hospital were enrolled prospectively. All subjects underwent 99Tc m-MIBI SPECT/CT scan. The SUV max of 8 bilateral representative muscles, including rectus capitis posterior major, obliquus capitis inferior, splenius capitis, semispinalis, sternocleidomastoid, trapezius, musculus scalenus muscle and levator scapulae were evaluated in control group. In PCD group, muscles with abnormal uptake were determined. ROI was drawn and SUV max was measured. Independent-sample t test was used to analyze the differences of SUV max between normal and abnormal muscles. The detecting rates of neck MRI and SPECT/CT for abnormal muscles were analyzed by χ2 test. Results:Normal muscles of healthy subjects showed mild symmetrical radioactivity distribution, with the SUV max of 1.10±0.19. A total of 60 muscles with abnormal uptake in 10 patients were found, including 7 rectus capitis posterior major, 10 obliquus capitis inferior, 8 splenius capitis, 8 semispinalis, 10 sternocleidomastoid, 5 trapezius, 3 musculus scalenus muscle and 9 levator scapulae. The SUV max of muscles with abnormal uptake was 1.81±0.43, which was higher than that of normal muscles ( t=17.05, P<0.001). Only 30 pieces abnormal hypertrophy muscle were found by neck MRI, and the detecting rate was much lower than that of SPECT/CT (18.75%(30/160) vs 37.50%(60/160); χ2=28.03, P<0.001). Conclusion:99Tc m-MIBI SPECT/CT may be a useful method for identifying dystonic muscles and a guide to precision therapy in patients with PCD.

Value of SPECT myocardial perfusion imaging and coronary flow reserve combined with coronary artery calcium score in the diagnosis of obstructive coronary artery disease / 中华核医学与分子影像杂志

Objective:To study the value of myocardial perfusion imaging (MPI) and coronary flow reserve (CFR) combined with coronary artery calcium score (CACS) in the diagnosis of obstructive coronary artery disease (CAD).Methods:From January 2019 to December 2020, 96 confirmed or suspective CAD patients (65 males, 31 females; age: 30-81 years) who completed rest/stress MPI, CFR and CACS defection in Fuwai Central China Cardiovascular Hospital were retrospectively analyzed. Coronary angiography (CAG) was used as the diagnostic standard to calculate the sensitivity and accuracy of MPI, CFR and MPI/CFR combined with CACS in the diagnosis of CAD. The χ2 test was used to compare the diagnostic efficiency of different methods. Results:The diagnostic sensitivity of MPI was 76.06%(54/71), and the accuracy was 75.00%(72/96), while the sensitivity increased to 97.18%(69/71; χ2=13.67, P<0.001) and the accuracy increased to 87.50%(84/96; χ2=4.92, P=0.020) with significant differences after combined with CACS. The sensitivity and accuracy of CFR were 91.55%(65/71)and 87.50%(84/96), which increased to 97.18%(69/71; χ2=2.12, P=0.137) and 89.58%(86/96; χ2=0.21, P=0.411) with no significant differences after combined with CACS. The sensitivity of MPI in the diagnosis of three-vessel CAD was 70.00%(21/30), which increased to 100%(30/30; χ2=7.75, P=0.004) after combined with CACS; while the sensitivity of MPI combined with CACS in the diagnosis of single-vessel and double-vessel CAD were not significantly improved ( χ2 values: 3.29, 1.51, P values: 0.114, 0.416). Conclusion:The combination of MPI and CACS can significantly improve the diagnostic efficiency of CAD, contributed by the improvement of the diagnostic sensitivity in three-vessel disease; whereas the diagnostic efficiency of CFR for CAD is not significantly improved after combined with CACS.

Establishment of the normal reference values of left ventricular function parameters evaluated by CZT SPECT stress gated myocardial perfusion imaging in low-likelihood of stable coronary artery disease / 中华核医学与分子影像杂志

Objective:To establish the normal reference value of left ventricular function parameters by cadmium-zinc-tellurium (CZT) SPECT stress gated myocardial perfusion imaging (G-MPI) in low-likelihood of stable coronary artery disease (SCAD).Methods:From March 2022 to August 2022, 348 consecutive SCAD patients (146 males, 202 females, age (58±10) years) who underwent exercise or pharmacological stress G-MPI (CZT SPECT) in Beijing Anzhen Hospital, Capital Medical University were retrospectively recruited. Left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF) were acquired using quantitative gated SPECT (QGS) analysis. EDV and ESV were corrected by body surface area (BSA) to obtain EDV index (EDVI) and ESV index (ESVI), respectively. Independent-sample t test, one-way analysis of variance and Mann-Whitney U test were used for data analysis. The influences of EDV, ESV, EDVI, ESVI and LVEF were analyzed by multiple regressions for linear models. Results:There were 314 patients with low-likelihood of SCAD (128 males, 186 females, age (58±10) years) and 34 normal controls (18 males, 16 females, age (55±10) years). There were no significant differences of basic clinical characteristics and left ventricular function parameters in different genders between 2 groups ( z values: from -1.74 to -0.02, t values: from -1.16 to 1.17, all P>0.05). Using the 95% CI as the cut-off value for left ventricular function parameters in patients with a low-likelihood of SCAD, the upper limits of EDV, ESV, EDVI and ESVI in females and males were 84 and 111 ml, 30 and 44 ml, 47 and 54 ml/m 2, 17 and 21 ml/m 2, respectively, and the lower limit of LVEF in females and males were 58% and 55%, respectively. In the low-likelihood of SCAD group, the EDV ((58±13) vs (77±17) ml) and ESV ((16±7) vs (26±9) ml) of females were smaller than those of males ( t values: 10.65, 10.35, both P<0.001), while LVEF of females was higher than that of males ((72±7)% vs (67±6)%; t=-6.23, P<0.001). However, there were no significant differences in left ventricular function parameters among different age groups with the same gender ( F values: 0.12-2.19, all P>0.05). Based on multiple regression for linear models, the primary predictors of EDV, ESV and LVEF were gender and weight ( β values: from -0.380 to 0.358, all P<0.05). Conclusions:Normal reference values of left ventricular function parameters are established by CZT SPECT stress G-MPI in low-likelihood of SCAD patients. Left ventricular EDV and ESV of females are smaller than those of males, while LVEF of females is higher than that of males. The influence of gender on left ventricular function parameters should be considered in clinical practice.

Exploring risk factors for combined coronary microvascular dysfunction in patients with ischemia and non-obstructive coronary artery disease / 中华核医学与分子影像杂志

Objective:To investigate the risk factors for combined coronary microvascular dysfunction (CMD) in patients with ischemia and non-obstructive coronary artery disease (INOCA).Methods:From October 2020 to May 2022, 100 INOCA patients with myocardial ischemic symptoms who underwent coronary angiography (CAG) suggestive of <50% stenosis in all three coronary arteries at the Tenth People′s Hospital of Tongji University were prospectively recruited. Myocardial perfusion imaging (MPI), transthoracic echocardiography and cadmium-zinc-telluride (CZT) SPECT coronary flow quantification were performed in the same month, and 93 INOCA patients (36 males and 57 females, age (63.0±10.9) years) were finally included. CMD was defined as coronary flow reserve (CFR)<2.5. Independent-sample t test, Mann-Whitney U test and χ2 test were used to compare MPI results and left ventricular volume parameters between CMD and non-CMD groups. ROC curve analysis was used to analyze the efficacy of each index in predicting CMD, and independent risk factors for CMD were screened by multivariate logistic regression analysis. Results:Among 93 INOCA patients, 29 were in the CMD group and 64 were in the non-CMD group. The age, proportion of hypertension, left ventricular mass index (LVMI), summed stress score (SSS), summed difference score (SDS), left ventricular internal diameter systolic (LVIDS), interventricular septum thickness (IVST), and left ventricular posterior wall thickness (LVPWT) in the CMD group were higher than those in the non-CMD group ( t values: 2.42-3.76, χ2=8.94, z values: -3.31, -3.41, all P<0.05). ROC curve analysis showed that LVMI, SSS, SDS, LVPWT, IVST and age were significant in predicting CMD (AUCs: 0.67-0.72). Multivariate logistic regression analysis showed that LVMI (odds ratio ( OR)=1.08, 95% CI: 1.01-1.17), SDS ( OR=5.37, 95% CI: 1.95-14.78), hypertension ( OR=5.68, 95% CI: 1.34-24.18) and age ( OR=1.10, 95% CI: 1.03-1.18) were risk factors for CMD. Conclusion:LVMI, SDS, hypertension and age are strongly associated with combined CMD in INOCA patients, which can be used for early risk stratification of INOCA patients.

Relationship between coronary flow reserve by CZT SPECT and invasive coronary fractional flow reserve and its potential clinical value / 中华核医学与分子影像杂志

Objective:To evaluate the relationship between regional coronary flow reserve (CFR) obtained from cadmium-zinc-telluride SPECT(CZT SPECT) myocardial functional perfusion imaging (MFPI) and invasive fractional flow reserve (FFR) measured during coronary angiography (CAG) and its clinical value in guiding coronary interventions.Methods:Forty-two patients (30 males, 12 females, age (63.3±9.8) years) who completed CZT SPECT MFPI in the First Affiliated Hospital of Nanjing Medical University from June 2022 to September 2022 and underwent CAG within 3 months were included retrospectively. The concordance of CFR and FFR for diagnosing myocardial ischemia (CFR<2.0 and FFR<0.8) was calculated at the vascular level. The diagnostic efficacy of coronary stenosis≥70% for decreased myocardial blood flow (CFR<2.0) was calculated. Kappa test was used to analyze the data. Results:A total of 126 major coronary arteries were identified in 42 patients, of which 30(23.8%) had a CFR<2.0 by CZT SPECT and 33(26.2%) had stenosis≥70% in CAG. A total of 32 coronary vessels were performed with MFPI CFR and FFR measurements, of which 6 were both decreased and 21 were both normal, so the concordance rate was 84.4%(27/32)( Kappa=0.612, P<0.001). Among 33 coronary vessels with stenosis≥70%, 13 were with CFR≥2.0. Among 30 coronary vessels with CFR<2.0, 10 were with stenosis<70%. When using stenosis≥70% to diagnose CFR decreasing, the sensitivity was 66.7%(20/30), specificity was 86.5%(83/96), positive predictive value was 60.6%(20/33), negative predictive value was 89.2%(83/93), and accuracy was 81.7%(103/126). Conclusions:The concordance between CFR and FFR for the diagnosis of myocardial ischemia is good. Nearly 1/3 of the coronary arteries with decreased CFR have stenosis<70%, whereas nearly 40% of the coronary arteries with stenosis≥70% are not result in myocardial ischemia. Regional CFR determined by CZT SPECT may have potentially significant clinical value in the diagnosis of coronary artery disease and decision-making of coronary intervention.

Evaluation of the efficacy of balloon pulmonary angioplasty in chronic thromboembolic pulmonary hypertension using pulmonary perfusion tomography imaging / 中华核医学与分子影像杂志

Objective:To evaluate the efficacy of balloon pulmonary angioplasty (BPA) in chronic thromboembolic pulmonary hypertension (CTEPH) using 99Tc m-macroaggregated albumin (MAA) pulmonary perfusion tomography imaging. Methods:Twenty-five patients (4 males, 21 females; age (56.5±12.3) years) with CTEPH who underwent BPA from January 2017 to April 2020 in Beijing Chaoyang Hospital, Capital Medical University were enrolled retrospectively. Effect of BPA on the improvement of pulmonary lobe/pulmonary segment perfusion was analyzed, and the proportions of improved and unimproved pulmonary lobe/pulmonary segment perfusion by BPA were calculated. The percentages of perfusion defect scores (PPDs%) of lung perfusion tomography imaging before BPA and after 4-6 times BPA were compared and analyzed (paired t test). The correlations between PPDs% and mean pulmonary artery pressure (mPAP) before BPA and after BPA were analyzed respectively, and the correlation between decreased percentage of PPDs% and decreased percentage of mPAP after BPA were also analyzed (Pearson correlation analysis). Results:Among 150 lobes of 25 patients, 96.00%(144/150) lobes showed perfusion abnormalities before BPA. After BPA, 11.11%(16/144) showed complete improvement, 57.64%(83/144) showed partial improvement, and 31.25%(45/144) showed no improvement. Among 450 pulmonary segments of 25 patients, 62.44%(281/450) showed perfusion abnormalities before BPA. After BPA, 30.60%(86/281), 37.37%(105/281), 32.03%(90/281) showed complete, partial and no improvement, respectively. The post-BPA PPDs% was significantly lower than that of pre-BPA ((39.08±10.88)% vs (57.88±10.46)%; t=10.40, P<0.001). The post-BPA mPAP was significantly lower than that of pre-BPA ((32.36±10.57) vs (49.08±10.23) mmHg; 1 mmHg=0.133 kPa; t=10.25, P<0.001). There was no significant correlation between PPDs% and mPAP either before BPA ( r=0.01, P=0.953) or after BPA ( r=0.27, P=0.199), but there was a positive correlation between the changes of PPDs% and mPAP ( r=0.40, P=0.045). Conclusions:BPA can significantly improve the pulmonary perfusion and reduce mPAP in CTEPH patients. Pulmonary perfusion tomography imaging can be used to evaluate the efficacy of BPA in CTEPH.

Correlation between PET-CT and ct in the staging after the treatment of head and neck squamous cell carcinoma

Abstract Objective: The aim of this study is to find out if a single imaging test is enough to follow-up on an oncological post-treatment patient. In such a case, we would know which was more valuable after comparing the two, by CT or PET-CT. Methods: Between January 2012 and July 2018, we collected data from all patients with previous medical history who were treated with a head and neck squamous cell carcinoma in our hospital, through surgery or by using an organ preservation protocol which we had done. Patients were required to have a CT and a PET-CT performed in a maximum period of 30 days between techniques. We compared the post post-treatment stage given to each case by using only the physical examination (only the CT and the PET-CT), with the ones given by the Tumor Board. After treatment, we analysed the similarity through Cramer's V statistic test. Results: We performed a comparative analysis, obtaining a correlation of 0.426 between the stages given by the Tumor Board and the one assigned based on physical examination, without imaging techniques. By only using the computed tomography as an imaging method the correlation was 0.565, whereas with only the use of positron emission computed technology, it was estimated at 0.858. When we compared the statistical association between stages using exclusively one of the two imaging techniques, the correlation was 0.451. Conclusion: Independent of the modality, we have demonstrated that in patients who have received previous treatment, there was a higher correlation in the stages with respect to the diagnostic method conducted by the Tumor Board using PET-CT as the sole image. Level of evidence: Level 1.

Magnetic resonance and dopamine transporter imaging for the diagnosis of Parkinson´s disease: a narrative review / Ressonância magnética e neuroimagem do transportador de dopamina no diagnóstico da doença de Parkinson: uma revisão narrativa

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.

Calidad de la imagen de tomografía computarizada versus dosis en estudios híbridos: resultados preliminares en maniquí

RESUMEN Fundamento: los estudios híbridos producen una dosis total de radiación que es resultado de la dosis proveniente del radiofármaco y la emitida por la tomografía computarizada, por eso la optimización es indispensable. Objetivo: evaluar la relación de la dosis de tomografía computarizada con algunos parámetros de calidad de la imagen en protocolos de estudios híbridos. Métodos: para evaluar la calidad de la imagen se emplearon los maniquíes de Catphan y de Livermore en 12 protocolos preestablecidos de un equipo de tomografía por emisión del fotón único Mediso. Los datos de los descriptores de dosis de cada estudio se obtuvieron del cabezal DICOM. Se compararon los parámetros de calidad de imagen clásicos como ruido y la MTF 50 % para el maniquí de Catphan, y otros como la relación contraste ruido, el promedio de números de Hounsfield y su desviación estándar en las regiones de interés de los órganos correspondientes, en el maniquí de Livermore. Se analizó la relación de estos parámetros de calidad con los descriptores de dosis de los diferentes protocolos. Resultados: los parámetros relacionados con la calidad en el maniquí de Catphan no mostraron diferencias significativas (p<0,05) entre los diferentes protocolos para estudios híbridos. Se encontraron diferencias significativas entre los protocolos clínicos con diferentes calidades y el protocolo clínico estándar, para el maniquí antropomórfico, en la desviación estándar de los números de Hounsfield y en la relación contraste ruido (p<0,05). Conclusiones: el estudio de la relación contraste ruido y la desviación de los números de tomografía computarizada en las regiones de interés pueden servir de parámetro cuantitativo para la optimización de dosis en escenario clínico.

ABSTRACT Background: hybrid studies produce a total radiation dose that is the result of the dose imparted by the radiopharmaceutical and that emitted by the computed tomography, therefore optimization is essential. Objective: to evaluate the relationship of the computed tomography dose with some image quality parameters in hybrid study protocols. Methods: to evaluate the image quality, the Catphan and Livermore Phantom were used in 12 pre-established protocols of a Mediso single photon emission tomography equipment. The data for the dose descriptors for each study were obtained from the DICOM head. The classic image quality parameters such as noise and the MTF 50% for the Catphan manikin, and others such as the contrast-noise ratio, the average of Hounsfield numbers and their standard deviation in the regions of interest of the corresponding organs were compared, in Livermore's mannequin. The relationship of these quality parameters with the dose descriptors of the different protocols was analyzed. Results: the quality-related parameters in the Catphan manikin did not show significant differences (p <0.05) between the different protocols for hybrid studies. Significant differences were found between the clinical protocols with different qualities and the standard clinical protocol, for the anthropomorphic manikin, in the standard deviation of the Hounsfield numbers and in the contrast-to-noise ratio (p <0.05). Conclusions: the study of the contrast noise ratio and the deviation of the computed tomography numbers in the regions of interest can serve as a quantitative parameter for the optimization of doses in the clinical setting.

Forma aguda de histoplasmose em paciente imunocompetente: relato de caso / Acute form of histoplasmosis in immunocompetent patient: case report

A histoplasmose é uma doença granulomatosa infecciosa sistêmica cuja transmissão é aerógena e a contaminação se dá pelo contato com fezes de aves e morcegos, depende da exposição e da imunidade do paciente. Trata-se de uma doença com difícil diagnóstico, dada a semelhança dos sintomas com os de outras doenças granulomatosas infecciosas, principalmente em pacientes imunocompetentes, visto que a regressão é geralmente espontânea. Um homem de 34 anos, branco, natural e procedente de Atibaia, previamente hígido, iniciou quadro de dor e edema no tornozelo esquerdo, e evoluiu com dispneia progressiva, com piora ao decúbito, acompanhada de sudorese noturna, tosse seca e febre baixa. Foi realizado o exame de tomografia computadorizada (TC) de tórax sem contraste, que evidenciou espessamento difuso das paredes brônquicas, de aspecto inflamatório, micronódulos esparsos bilateralmente. Paciente apresentou PCR elevado, COVID, sorologias, BAAR e hemoculturas negativas, punção articular e ecocardiograma sem alterações. Optado por COXCIP 4, sulfametoxazol-trimetoprim e anfotericina B de forma empírica. Pesquisa de fungos em escarro positivo; leveduras e lavado brônquico sugestivos de histoplasmose. Evoluiu com insuficiência respiratória necessitando de intubação orotraqueal, posteriormente, traqueostomia e apesar do tratamento antifúngico, evoluiu com óbito após 21 dias. A histoplasmose é uma doença grave, com diversas formas clínicas e prognóstico normalmente autolimitado, mas que pode ser fatal, mesmo em pacientes previamente imunocompetentes.

Histoplasmosis is a systemic infectious granulomatous disease whose transmission is airborne, and contamination occurs through contact with bird and bat feces, depending on the exposure and immunity of the patient. It is a disease with difficult diagnosis, given the similarity of symptoms with those of other infectious granulomatous diseases, especially in immunocompetent patients since regression is usually spontaneous. A 34-year-old Caucasian man from Atibaia, previously healthy, developed pain and swelling in his left ankle, progressing to progressive dyspnea, worsening in recumbency, accompanied by night sweats, dry cough and low-grade fever. A non-contrast-enhanced computed tomography (CT) scan of the chest was performed, which showed diffuse thickening of the bronchial walls, with an inflammatory appearance, and bilaterally sparse micronodules. Patient had high C-reactive protein, COVID, serology, BAAR and negative blood cultures, joint puncture, and echocardiogram without changes. Empirically opted for COXCIP 4, trimethoprim-sulfamethoxazole and amphotericin B. Search for fungi in positive sputum, yeasts, and bronchial lavage suggestive of histoplasmosis. He envolved with respiratory failure requiring orotracheal intubation, later tracheostomy and despite antifungal treatment, he died after 21 days. Histoplasmosis is a serious disease, with several clinical forms and a prognosis that is usually self-limiting, but it can be fatal, even in previously immunocompetent patients